ENGINEERED ANTI-SARS-COV-2 ANTIBODIES AND METHODS OF USING THE SAME REFERENCE TO AN ELECTRONIC SEQUENCE LISTING The contents of the electronic sequence listing (442WO_SeqListing.xml; Size: 188,416 kilobytes; and Date of Creation: November 15, 2023) are herein incorporated by reference in their entirety. BACKGROUND A novel betacoronavirus emerged in late 2019. As of March 6, 2023, approximately 676 million cases of infection by this virus (termed, among other names, SARS-CoV-2s), were confirmed worldwide, and had resulted in approximately 6.87 million deaths. Modalities for preventing, treating, and diagnosing SARS-CoV-2 infections, including by developing SARS-CoV-2 variants, are needed. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1A-1D show neutralization of SARS-CoV-2, SARS-CoV-2 G504D variant, and SARS-CoV VSV-PVS by certain antibodies of the present disclosure derived from mammalian cells. (A) Percent neutralization of SARS-CoV-2 (Wuhan- Hu-1). (B) Percent neutralization of SARS-CoV. (C) Percent neutralization of SARS- CoV-2-G504D variant. (D) Calculated neutralization IC50 values from Figures 1A- 1C. “S2X259v5-parental” and “S2X259v7” antibodies were included as comparators in these experiments. Figures 2A-2D show neutralization of SARS-CoV-2 and SARS-CoV-2 B.1.617.2 by certain antibodies of the present disclosure produced in mammalian cells. Figures 2A and 2B show neutralization curves and neutralization IC50 values (respectively) from a first set of experiments. Figures 2C and 2D show neutralization curves and neutralization IC50 values (respectively) from experimental repeats. “S2X259v5 parental”, “S2E12”, and “VIR7831” (aka sotrovimab, also called S309-N55Q-MLNS and VIR-7831) were included as comparators in these experiments. Figures 3A-3K show binding by antibodies to clade 1a, clade 1b, clade 2, and clade 3 sarbecoviruses. The x-axis text ELN31024- … refers to a capture solution comprising a certain antibody. In this text, the suffix (e.g., “-69”, “-269”, “-1”, “-221”, “-77”, “-45”, “-189”, “-354”, “-543”) designates the antibody in the capture solution. Parental antibodies S2X259v7 (Figure 3D) and S2X259v5 (Figure 3H) are included as comparators. Figures 4A and 4B provide tables summarizing IC50 results from neutralization experiments (SARS-CoV-2/SARS-CoV/SARS-CoV-2 delta/SARS-CoV- 2 G504D variant) (4A) and neutralization fold-change vs. S2X259v5 (4B) of certain antibodies of the present disclosure. The Capture 1 solutions in the tables are as shown in Figures 3A-3K. “Parental S2X259v5” is included as a comparator. Data from repeat experiments (“rep”) is shown, and, in Figure 4B, the mean. Figure 4C shows neutralization of SARS-CoV-2 and SARS-CoV-2 delta variant by comparator antibodies VIR-7831 (sotrovimab) and S2E12. Figures 4D-4E show binding (biolayer interferometry app. KD values) of certain antibodies of the present disclosure (S2X259v5 parent included as comparator) against sarbecoviruses of clade 1 (1a or 1b), clade 2, and clade 3. The Capture 1 solutions in the tables are as shown in Figures 3A-3K and 4A-4B. The antibodies tested in Figures 4D and 4E were derived from mammalian cells. Figure 5 provides data assessing potential polyreactivity of certain antibodies of the present disclosure. “…parental”, “MPE8” (anti-RSV/anti-MPV), and “FI6” (anti- influenza HA) antibodies were included as comparators. Figures 6A-6D summarize certain characteristics of certain antibodies, wherein the antibodies were derived from yeast cells. Figure 7 shows Octet quantification of certain purified antibodies of the present disclosure. Figure 8 shows IC50 results from neutralization experiments for S2X259-v50 variant antibodies (i.e., engineered variants derived from S2X259-v50) versus SARS- CoV-2 BA.5. S2X259-v50 is shown (as “S2X259.v50”) as a comparator. Figure 9 shows neutralization results of certain S2X259-v50 variants tested vs. a panel of SARS-CoV-2 and SARS-CoV-1 pseudoviruses. Above the solid horizontal line = IC50 (ng/ml) vs. BA.5 D504G. Below the solid horizontal line = fold-change (IC50 of the parental antibody (S2X259-v50) / IC50 of the indicated variant antibody. Figure 10 shows neutralization curves for S2X259-v50 and S2X259-774 vs. a panel of SARS-CoV-2 pseudoviruses. “WT” – Wuhan-Hu-1. Figure 11 shows neutralization IC50 values for S2X259-v50 and certain variant antibodies against a panel of SARS CoV-2 and SARS-CoV-1 pseudoviruses. Figure 12 shows correlation of neutralizing potency across different SARS- CoV-2 strains (see x- and y-axis of plots) for S2X259-v50 and the indicated variants (shown in the plots according to the plate well; see Key). Figure 13 shows a summary of neutralization data for certain S2X259-v50 variant antibodies. Figure 14A shows neutralization IC50 values for the indicated antibodies against a panel of SARS-CoV-2 strains and SARS-CoV-1. “100000” and “100000.00” indicate that no neutralization was detected. “E09” = S2X259-774. Figure 14B summarizes fold-change in IC50 values for S2X259-v50 variants vs. the parental antibody, across SARS-CoV-2 strains and SARS-CoV-1. Figure 15 shows binding and neutralization correlation plots for S2X259-v50 variant antibodies across SARS-CoV-2 strains and SARS-CoV-1. Figure 16 shows (left) a panel of SARS coronaviruses against which binding affinity of certain S2X259 variant antibodies for RBD was measured, and (right) the top neutralizing antibodies (identified by well plate; well plate coding is as in Figure 11; e.g. “E9” corresponds to S2X259-774; “F12” corresponds to the parental antibody S2X259-v50) against each strain. Figure 17 summarizes an experimental setup for a surface plasmon resonance (SPR) assay measuring binding of the certain antibodies of the present disclosure against a panel of RBDs. Figure 18 shows binding data for negative control antibody D12 (aRSV) against BA.4/5 and BA.4.6 in a quality control check. Figure 19 shows correlation of neutralization (IC50) versus binding (KD for RBD, as measured by SPR) results for S2X259-v50 variant antibodies against the indicated CoVs. “E9” = S2X259-774. Figure 20 shows fold-change improvement in neutralization and binding for certain S2X259-v50 variant antibodies against the S2X259-v50 parental antibody. Figure 21 shows neutralization and binding results of certain S2X259-v50 variant antibodies against SARS-CoV-2 Wuhan Hu-G504D. Parental antibody S2X259-v50 = second dot from left at the top of the graph (along dashed line); S2X259-774 = bottom left-most dot. Figure 22 shows a cladogram of coronaviruses and antibodies (S2E12, S309, ADG-2, S2X259) that can bind to the indicated coronaviruses. Figure 23 shows binding affinity (KD, reported as nanomolar) of S2X259-v50 and variant antibodies to ZC45 and BGR08. Figure 24 shows (left) S2X259-v50 binding affinity (KD) correlations between CoV strains and (right) affinity correlations for (top) BGR08 or ZC45 versus SARS- CoV-1 and (bottom) BA.46 versus BA.4 or BA.5 by S2X259-v50 variant antibodies. Figure 25 shows example sensorgrams for S2X259-v50 (left, shown as “F12”) and S2X259-774 (right, shown as “E09”). Figure 26 shows a summary of binding affinity (KD) for S2X259-v50 and certain variant antibodies against the indicated CoVs. NB indicates no binding. “<0.01” for S2X259-780 vis-à-vis BA.2 indicates that KD was below the instrument’s detection. Figure 27 summarizes fold-improvement in binding affinity for the variant antibodies, with reference to parental S2X259-v50. NB indicates no binding. “>239x” for S2X259-780 vis-à-vis BA.2 indicates KD was below the instrument’s detection (<1e-06 s-1). DETAILED DESCRIPTION Provided herein are engineered antibodies and antigen-binding fragments that are capable of binding to SARS-CoV-2 coronavirus (e.g., a SARS-CoV-2 surface glycoprotein and/or RBD, as described herein, in a SARS-CoV-2 virion and/or expressed on the surface of a host cell, such as a cell infected by the SARS-CoV-2 coronavirus). A host cell can be, for example, a lung cell, a CHO cell (such as, for example, an ExpiCHO cell transfected to express the surface glycoprotein), or the like. In certain embodiments, presently disclosed antibodies and antigen-binding fragments can neutralize a SARS-CoV-2 infection in an in vitro model of infection and/or in a human subject. Disclosed antibodies and antigen-binding fragments include, for example, engineered variants of S2X259, which is a monoclonal antibody isolated from a human patient who recovered from a SARS-CoV-2 infection (Tortorici, M.A., Czudnochowski, N., Starr, T.N. et al. Broad sarbecovirus neutralization by a human monoclonal antibody. Nature 597, 103–108 (2021). doi.org/10.1038/s41586-021-03817-4). S2X259 recognizes a highly conserved cryptic epitope of the receptor-binding domain and cross-reacts with spikes from all clades of sarbecovirus. S2X259 neutralizes spike- mediated cell entry of SARS-CoV-2, including variants of concern (B.1.1.7, B.1.351, P.1, and B.1.427/B.1.429), as well as a wide spectrum of human and potentially zoonotic sarbecoviruses through inhibition of angiotensin-converting enzyme 2 (ACE2) binding to the receptor-binding domain. As taught herein, deep-mutational scanning and in vitro escape selection experiments demonstrate that S2X259 possesses an escape profile that is limited to a single substitution, G504D. Prophylactic and therapeutic administration of S2X259 protects Syrian hamsters (Mesocricetus auratus) against challenge with the prototypic SARS-CoV-2 and the B.1.351 variant of concern. Certain embodiments provide engineered variant antibodies and antigen-binding fragments of S2X259 that have one or more improved property as compared to S2X259 (e.g., binding affinity, breadth of binding, and/or neutralization of one or more sarbecovirus, such as one or more SARS-CoV-2 strain (such as comprising a G504D mutation)( and/or SARS-CoV and/or ZC45 and/or BGR08. In some embodiments, an antibody or antigen-binding fragment is provided that can bind to and, in certain embodiments, can neutralize, a SARS-CoV-2 comprising a G504D mutation.In certain embodments, presently disclosed antibodies and antigen-binding fragments are capable of binding to and/or neutralizing two, three, or more sarbecoviruses and/or SARS-CoV- 2 viruses, such as, for example, a sarbecovirus of clade 1a, a sarbecovirus of clade 1b, a sarbecovirus of clade 2, a sarbecovirus of clade 3, and/or a variant of SARS-CoV-2. In some embodiments, a sarbecovirus is from clade 1a, clade 1b, clade 2, or clade 3. In some embodiments, a sarbecovirus comprises a SARS-CoV-2, a SARS-CoV-2 G504D variant, a SARS-CoV delta variant, a SARS-CoV-2 omicron variant, a SARS-CoV-2 BA.2, a SARS-CoV-2 BA.4, a SARS-CoV-2 BA.5, a SARS-CoV-2 BA.4/5, a SARS- CoV-2 BA.4.6, a ZC45, a BGR08, a SARS-CoV, or any combination thereof. In some embodiments, an antibody or antigen-binding fragment is provided that comprises the six CDRs of S2X259-774. In certain embodiments, CDRH1 comprises or consists of the amino acid sequence GGIDNTYT (SEQ ID NO.:138), CDRH2 comprises or consists of the amino acid sequence ILMSGWA (SEQ ID NO.:136), CDRH3 comprises or consists of the amino acid sequence ARGFHSDYYGWGDDDAFDF (SEQ ID NO.:137), CDRL1 comprises or consists of the amino acid sequence NSNIGAGYD (SEQ ID NO.:43), CDRL2 comprises or consists of the amino acid sequence GNS (SEQ ID NO.:44), and CDRL3 comprises or consists of the amino acid sequence QSYDSSLSEPTWV (SEQ ID NO.:139). In certain embodiments, the antibody or antigen-binding fragment comprises, in a VH, the amino acid sequences GGIDNTYT (SEQ ID NO.:138), ILMSGWA (SEQ ID NO.:136), and ARGFHSDYYGWGDDDAFDF (SEQ ID NO.:137), and in a VL, the amino acid sequences NSNIGAGYD (SEQ ID NO.:43), GNS (SEQ ID NO.:44), and QSYDSSLSEPTWV (SEQ ID NO.:139). In certain embodiments, the antibody or antigen-binding fragment a VH and a VL that have at least 80%, at least 85%, at least 90%, and least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity to, or comprise or consist of, the amino acid sequences set forth in SEQ ID NOs.:135 and 113, respectively. In certain embodiments, the antibody or antigen-binding fragment comprises the VH and VL amino acid sequences of S2X259-774 (SEQ ID NOs.:135 and 113, respectively). In particular embodiments, the antibody or antigen-binding fragment is provided as a human IgG1 isotype that optionally comprises M428L and N434S, and/or optionally comprises one or more other mutations, in the Fc. Also provided are polynucleotides that encode the antibodies and antigen- binding fragments, vectors, host cells, and related compositions, as well as methods of using the antibodies, nucleic acids, vectors, host cells, and related compositions to treat (e.g., reduce, delay, eliminate, or prevent) a SARS-CoV-2 infection in a subject and/or in the manufacture of a medicament for treating a SARS-CoV-2 infection in a subject. Further provided herein are antibodies and antigen-binding fragments that are capable of binding to multiple sarbecoviruses (e.g., a surface glycoprotein, as described herein, of one or more (e.g., one, two, three, four, five, six, or more) different sarbecovirus virions and/or expressed on the surface of a cell infected by two or more sarbecoviruses). In certain embodiments, presently disclosed antibodies and antigen- binding fragments can neutralize infection by two or more sarbecoviruses in an in vitro model of infection and/or in a human subject. Also provided are polynucleotides that encode the antibodies and antigen-binding fragments, vectors, host cells, and related compositions, as well as methods of using the antibodies, nucleic acids, vectors, host cells, and related compositions to treat (e.g., reduce, delay, eliminate, or prevent) infection by two or more sarbecoviruses in a subject and/or in the manufacture of a medicament for treating infection in a subject by two or more sarbecoviruses. Prior to setting forth this disclosure in more detail, it may be helpful to an understanding thereof to provide definitions of certain terms to be used herein. Additional definitions are set forth throughout this disclosure. As used herein, "sarbecovirus" refers to any betacoronavirus within lineage B, and includes lineage B viruses in clade 1a, clade 1b, clade 2, and clade 3. Examples of clade 1a sarbecoviruses are SARS-CoV and Bat SARS-like coronavirus WIV1 (WIV1). Examples of clade 1b sarbecoviruses are SARS-CoV-2 (including Wuhan-Hu-1 and variants thereof, e.g. a variant comprising a G504D mutation), RatG13, Pangolin- Guanxi-2017 (PANG/GX) and Pangolin-Guangdon-2019 (PANG/GD). Examples of clade 2 sarbecoviruses are Bat ZC45 (ZC45), Bat ZXC21 (ZXC21), YN2013, SC2018, SX2011, and RmYN02. Examples of clade 3 sarbecoviruses are BtkY72 and BGR2008. In some embodiments, an antibody or antigen-binding fragment thereof is capable of binding to: a sarbecovirus of clade 1a (e.g., SARS-CoV, WIV1, or both); a sarbecovirus of clade 1b (e.g., SARS-CoV-2, RatG13, Pangolin-Guanxi-2017 (PANG/GX), Pangolin-Guangdon-209, or any combination thereof); a sarbecovirus of clade 2; and/or a sarbecovirus of clade 3. In some embodiments, an antibody or antigen-binding fragment thereof is capable of binding to a sarbecovirus of clade 1a, a sarbecovirus of clade 1b, a sarbecovirus of clade 2, and a sarbecovirus of clade 3. In certain embodiments, an antibody or antigen-binding fragment thereof is capable of binding to a SARS-CoV-2 variant; e.g., a G504D variant (see e.g. Tortorici et al. Nature 597:103-108 and supplementary materials (2021), https://doi.org/10.1038/s41586-021-03817-4); a N501Y variant; a Y453F variant; a N439K variant; a K417V variant; a N501Y-K417N-E484K variant; a E484K variant; a California variant; a Brazilian variant; a Swiss variant; or any combination thereof. As used herein, "SARS-CoV-2", also referred to as "Wuhan seafood market phenomia virus", or "Wuhan coronavirus" or "Wuhan CoV", or "novel CoV", or "nCoV", or "2019 nCoV", or "Wuhan nCoV" is a betacoronavirus believed to be of lineage B (sarbecovirus). SARS-CoV-2 was first identified in Wuhan, Hubei province, China, in late 2019 and spread within China and to other parts of the world by early 2020. Symptoms of SARS-CoV-2 infection include fever, dry cough, and dyspnea. The genomic sequence of SARS-CoV-2 isolate Wuhan-Hu-1 is provided in SEQ ID NO.:1 (see also GenBank MN908947.3, January 23, 2020), and the amino acid translation of the genome is provided in SEQ ID NO.:2 (see also GenBank QHD43416.1, January 23, 2020). Like other coronaviruses (e.g., SARS-CoV-1), SARS-CoV-2 comprises a "spike" or surface ("S") type I transmembrane glycoprotein containing a receptor binding domain (RBD). RBD is believed to mediate entry of the lineage B SARS coronavirus to respiratory epithelial cells by binding to the cell surface receptor angiotensin-converting enzyme 2 (ACE2). In particular, a receptor binding motif (RBM) in the virus RBD is believed to interact with ACE2. The amino acid sequence of the SARS-CoV-2 Wuhan-Hu-1 surface glycoprotein is provided in SEQ ID NO.:3. Antibodies and antigen-binding fragments of the present disclosure are capable of binding to a SARS CoV-2 surface glycoprotein (S), such as that of Wuhan-Hu-1. For example, in certain embodiments, an antibody or antigen-binding fragment binds to an epitope in Wuhan-Hu-1 S protein RBD. The amino acid sequence of SARS-CoV-2 Wuhan-Hu-1 RBD is provided in SEQ ID NO.:4. SARS-CoV-2 S protein has approximately 73% amino acid sequence identity with SARS-CoV S protein. The amino acid sequence of SARS-CoV-2 RBM is provided in SEQ ID NO.:5. SARS-CoV-2 RBD has approximately 75% to 77% amino acid sequence similarity to SARS–CoV-1 RBD, and SARS-CoV-2 RBM has approximately 50% amino acid sequence similarity to SARS-CoV RBM. Unless otherwise indicated herein, SARS-CoV-2 Wuhan-Hu-1 refers to a virus comprising the amino acid sequence set forth in any one or more of SEQ ID NOs.:2, 3, and 4, optionally with the genomic sequence set forth in SEQ ID NO.:1. There have been a number of emerging SARS-CoV-2 variants. Some SARS- CoV-2 variants contain a G504D variant. Some SARS-CoV-2 variants contain an N439K mutation, which has enhanced binding affinity to the human ACE2 receptor (Thomson, E.C., et al., The circulating SARS-CoV-2 spike variant N439K maintains fitness while evading antibody-mediated immunity. bioRxiv, 2020). Some SARS-CoV- 2 variants contain an N501Y mutation, which is associated with increased transmissibility, including the lineages B.1.1.7 (also known as 20I/501Y.V1 and VOC 202012/01; (del69-70, del144, N501Y, A570D, D614G, P681H, T716I, S982A, and D1118H mutations)) and B.1.351 (also known as 20H/501Y.V2; L18F, D80A, D215G, R246I, K417N, E484K, N501Y, D614G, and A701V mutations), which were discovered in the United Kingdom and South Africa, respectively (Tegally, H., et al., Emergence and rapid spread of a new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) lineage with multiple spike mutations in South Africa. medRxiv, 2020: p.2020.12.21.20248640; Leung, K., et al., Early empirical assessment of the N501Y mutant strains of SARS-CoV-2 in the United Kingdom, October to November 2020. medRxiv, 2020: p.2020.12.20.20248581). B.1.351 also include two other mutations in the RBD domain of SARS-CoV2 spike protein, K417N and E484K (Tegally, H., et al., Emergence and rapid spread of a new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) lineage with multiple spike mutations in South Africa. medRxiv, 2020: p.2020.12.21.20248640). Other SARS-CoV-2 variants include the Lineage B.1.1.28, which was first reported in Brazil; the Variant P.1, lineage B.1.1.28 (also known as 20J/501Y.V3), which was first reported in Japan; Variant L452R, which was first reported in California in the United States (Pan American Health Organization, Epidemiological update: Occurrence of variants of SARS-CoV-2 in the Americas, January 20, 2021, available at reliefweb.int/sites/reliefweb.int/files/resources/2021-jan-2 0-phe-epi-update-SARS- CoV-2.pdf). Other SARS-CoV-2 variants include a SARS CoV-2 of clade 19A; SARS CoV-2 of clade 19B; a SARS CoV-2 of clade 20A; a SARS CoV-2 of clade 20B; a SARS CoV-2 of clade 20C; a SARS CoV-2 of clade 20D; a SARS CoV-2 of clade 20E (EU1); a SARS CoV-2 of clade 20F; a SARS CoV-2 of clade 20G; and SARS CoV-2 B1.1.207; and other SARS CoV-2 lineages described in Rambaut, A., et al., A dynamic nomenclature proposal for SARS-CoV-2 lineages to assist genomic epidemiology. Nat Microbiol 5, 1403–1407 (2020). The Alpha (B.1.1.7), Beta (B.1.351, B.1.351.2, B.1.351.3), Delta (B.1.617.2, AY.1, AY.2, AY.3; see also Mlcochova, P., Kemp, S.A., Dhar, M.S. et al. SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion. Nature (2021). https://doi.org/10.1038/s41586-021-03944-y), and Gamma (P.1, P.1.1, P.1.2) variants of SARS-CoV-2 circulating in the United States are classified as variants of concern by the U.S. Centers for Disease Control and Prevention (see https://www.cdc.gov/coronavirus/2019-ncov/variants/variant-i nfo.html). The foregoing SARS-CoV-2 variants, and the amino acid and nucleotide sequences thereof, are incorporated herein by reference. SARS-CoV is another betacoronavirus of lineage B (sarbecovirus) that causes respiratory symptoms in infected individuals. The genomic sequence of SARS-CoV Urbani strain has GenBank accession number AAP13441.1. In the present description, any concentration range, percentage range, ratio range, or integer range is to be understood to include the value of any integer within the recited range and, when appropriate, fractions thereof (such as one tenth and one hundredth of an integer), unless otherwise indicated. Also, any number range recited herein relating to any physical feature, such as polymer subunits, size or thickness, are to be understood to include any integer within the recited range, unless otherwise indicated. As used herein, the term "about" means ± 20% of the indicated range, value, or structure, unless otherwise indicated. It should be understood that the terms "a" and "an" as used herein refer to "one or more" of the enumerated components. The use of the alternative (e.g., "or") should be understood to mean either one, both, or any combination thereof of the alternatives. As used herein, the terms "include," "have," and "comprise" are used synonymously, which terms and variants thereof are intended to be construed as non-limiting. "Optional" or "optionally" means that the subsequently described element, component, event, or circumstance may or may not occur, and that the description includes instances in which the element, component, event, or circumstance occurs and instances in which they do not. In addition, it should be understood that the individual constructs, or groups of constructs, derived from the various combinations of the structures and subunits described herein, are disclosed by the present application to the same extent as if each construct or group of constructs was set forth individually. Thus, selection of particular structures or particular subunits is within the scope of the present disclosure. The term “consisting essentially of” is not equivalent to “comprising” and refers to the specified materials or steps of a claim, or to those that do not materially affect the basic characteristics of a claimed subject matter. For example, a protein domain, region, or module (e.g., a binding domain) or a protein “consists essentially of” a particular amino acid sequence when the amino acid sequence of a domain, region, module, or protein includes extensions, deletions, mutations, or a combination thereof (e.g., amino acids at the amino- or carboxy-terminus or between domains) that, in combination, contribute to at most 20% (e.g., at most 15%, 10%, 8%, 6%, 5%, 4%, 3%, 2% or 1%) of the length of a domain, region, module, or protein and do not substantially affect (i.e., do not reduce the activity by more than 50%, such as no more than 40%, 30%, 25%, 20%, 15%, 10%, 5%, or 1%) the activity of the domain(s), region(s), module(s), or protein (e.g., the target binding affinity of a binding protein). As used herein, “amino acid” refers to naturally occurring and synthetic amino acids, as well as amino acid analogs and amino acid mimetics that function in a manner similar to the naturally occurring amino acids. Naturally occurring amino acids are those encoded by the genetic code, as well as those amino acids that are later modified, e.g., hydroxyproline, γ-carboxyglutamate, and O-phosphoserine. Amino acid analogs refer to compounds that have the same basic chemical structure as a naturally occurring amino acid, i.e., an α-carbon that is bound to a hydrogen, a carboxyl group, an amino group, and an R group, e.g., homoserine, norleucine, methionine sulfoxide, methionine methyl sulfonium. Such analogs have modified R groups (e.g., norleucine) or modified peptide backbones, but retain the same basic chemical structure as a naturally occurring amino acid. Amino acid mimetics refer to chemical compounds that have a structure that is different from the general chemical structure of an amino acid, but that functions in a manner similar to a naturally occurring amino acid. As used herein, “mutation” refers to a change in the sequence of a nucleic acid molecule or polypeptide molecule as compared to a reference or wild-type nucleic acid molecule or polypeptide molecule, respectively. A mutation can result in several different types of change in sequence, including substitution, insertion or deletion of nucleotide(s) or amino acid(s). A “conservative substitution” refers to amino acid substitutions that do not significantly affect or alter binding characteristics of a particular protein. Generally, conservative substitutions are ones in which a substituted amino acid residue is replaced with an amino acid residue having a similar side chain. Conservative substitutions include a substitution found in one of the following groups: Group 1: Alanine (Ala or A), Glycine (Gly or G), Serine (Ser or S), Threonine (Thr or T); Group 2: Aspartic acid (Asp or D), Glutamic acid (Glu or Z); Group 3: Asparagine (Asn or N), Glutamine (Gln or Q); Group 4: Arginine (Arg or R), Lysine (Lys or K), Histidine (His or H); Group 5: Isoleucine (Ile or I), Leucine (Leu or L), Methionine (Met or M), Valine (Val or V); and Group 6: Phenylalanine (Phe or F), Tyrosine (Tyr or Y), Tryptophan (Trp or W). Additionally or alternatively, amino acids can be grouped into conservative substitution groups by similar function, chemical structure, or composition (e.g., acidic, basic, aliphatic, aromatic, or sulfur-containing). For example, an aliphatic grouping may include, for purposes of substitution, Gly, Ala, Val, Leu, and Ile. Other conservative substitutions groups include: sulfur-containing: Met and Cysteine (Cys or C); acidic: Asp, Glu, Asn, and Gln; small aliphatic, nonpolar or slightly polar residues: Ala, Ser, Thr, Pro, and Gly; polar, negatively charged residues and their amides: Asp, Asn, Glu, and Gln; polar, positively charged residues: His, Arg, and Lys; large aliphatic, nonpolar residues: Met, Leu, Ile, Val, and Cys; and large aromatic residues: Phe, Tyr, and Trp. Additional information can be found in Creighton (1984) Proteins, W.H. Freeman and Company. As used herein, “protein” or “polypeptide” refers to a polymer of amino acid residues. Proteins apply to naturally occurring amino acid polymers, as well as to amino acid polymers in which one or more amino acid residue is an artificial chemical mimetic of a corresponding naturally occurring amino acid, and non-naturally occurring amino acid polymers. Variants of proteins, peptides, and polypeptides of this disclosure are also contemplated. In certain embodiments, variant proteins, peptides, and polypeptides comprise or consist of an amino acid sequence that is at least 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 99.9% identical to an amino acid sequence of a defined or reference amino acid sequence as described herein. In certain embodiments, variant proteins, peptides, and polypeptides comprise or consist of an amino acid sequence that is at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% identical to an amino acid sequence of a defined or reference amino acid sequence as described herein. “Nucleic acid molecule” or “polynucleotide” or “polynucleic acid” refers to a polymeric compound including covalently linked nucleotides, which can be made up of natural subunits (e.g., purine or pyrimidine bases) or non-natural subunits (e.g., morpholine ring). Purine bases include adenine, guanine, hypoxanthine, and xanthine, and pyrimidine bases include uracil, thymine, and cytosine. Nucleic acid molecules include polyribonucleic acid (RNA), which includes mRNA, microRNA, siRNA, viral genomic RNA, and synthetic RNA, and polydeoxyribonucleic acid (DNA), which includes cDNA, genomic DNA, and synthetic DNA, either of which may be single or double stranded. If single-stranded, the nucleic acid molecule may be the coding strand or non-coding (anti-sense) strand. A nucleic acid molecule encoding an amino acid sequence includes all nucleotide sequences that encode the same amino acid sequence. Some versions of the nucleotide sequences may also include intron(s) to the extent that the intron(s) would be removed through co- or post-transcriptional mechanisms. In other words, different nucleotide sequences may encode the same amino acid sequence as the result of the redundancy or degeneracy of the genetic code, or by splicing. In some embodiments, the polynucleotide (e.g. mRNA) comprises a modified nucleoside, a cap-1 structure, a cap-2 structure, or any combination thereof. In certain embodiments, the polynucleotide comprises a pseudouridine, a N6-methyladenonsine, a 5-methylcytidine, a 2-thiouridine, or any combination thereof. In some embodiments, the pseudouridine comprises N1-methylpseudouridine. These features are known in the art and are discussed in, for example, Zhang et al. Front. Immunol., DOI=10.3389/fimmu.2019.00594 (2019); Eyler et al. PNAS 116(46): 23068-23071; DOI: 10.1073/pnas.1821754116 (2019); Nance and Meier, ACS Cent. Sci.2021, 7, 5, 748–756; doi.org/10.1021/acscentsci.1c00197 (2021), and van Hoecke and Roose, J. Translational Med 17:54 (2019); https://doi.org/10.1186/s12967-019-1804-8, which modified nucleosides and mRNA features are incorporated herein by reference.  Variants of nucleic acid molecules of this disclosure are also contemplated. Variant nucleic acid molecules are at least 70%, 75%, 80%, 85%, 90%, and are preferably 95%, 96%, 97%, 98%, 99%, or 99.9% identical a nucleic acid molecule of a defined or reference polynucleotide as described herein, or that hybridize to a polynucleotide under stringent hybridization conditions of 0.015M sodium chloride, 0.0015M sodium citrate at about 65-68ºC or 0.015M sodium chloride, 0.0015M sodium citrate, and 50% formamide at about 42ºC. Nucleic acid molecule variants retain the capacity to encode a binding domain thereof having a functionality described herein, such as binding a target molecule. “Percent sequence identity” refers to a relationship between two or more sequences, as determined by comparing the sequences. Preferred methods to determine sequence identity are designed to give the best match between the sequences being compared. For example, the sequences are aligned for optimal comparison purposes (e.g., gaps can be introduced in one or both of a first and a second amino acid or nucleic acid sequence for optimal alignment). Further, non-homologous sequences may be disregarded for comparison purposes. The percent sequence identity referenced herein is calculated over the length of the reference sequence, unless indicated otherwise. Methods to determine sequence identity and similarity can be found in publicly available computer programs. Sequence alignments and percent identity calculations may be performed using a BLAST program (e.g., BLAST 2.0, BLASTP, BLASTN, or BLASTX). The mathematical algorithm used in the BLAST programs can be found in Altschul et al., Nucleic Acids Res.25:3389-3402, 1997. Within the context of this disclosure, it will be understood that where sequence analysis software is used for analysis, the results of the analysis are based on the “default values” of the program referenced. “Default values” mean any set of values or parameters which originally load with the software when first initialized. The term “isolated” means that the material is removed from its original environment (e.g., the natural environment if it is naturally occurring). For example, a naturally occurring nucleic acid or polypeptide present in a living animal is not isolated, but the same nucleic acid or polypeptide, separated from some or all of the co-existing materials in the natural system, is isolated. Such nucleic acid could be part of a vector and/or such nucleic acid or polypeptide could be part of a composition (e.g., a cell lysate), and still be isolated in that such vector or composition is not part of the natural environment for the nucleic acid or polypeptide. "Isolated" can, in some embodiments, also describe an antibody, antigen binding fragment, polynucleotide, vector, host cell, or composition that is outside of a human body. The term “gene” means the segment of DNA or RNA involved in producing a polypeptide chain; in certain contexts, it includes regions preceding and following the coding region (e.g., 5ʹ untranslated region (UTR) and 3ʹ UTR) as well as intervening sequences (introns) between individual coding segments (exons). A “functional variant” refers to a polypeptide or polynucleotide that is structurally similar or substantially structurally similar to a parent or reference compound of this disclosure, but differs slightly in composition (e.g., one base, atom or functional group is different, added, or removed), such that the polypeptide or encoded polypeptide is capable of performing at least one function of the parent polypeptide with at least 50% efficiency, preferably at least 55%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, 99.9%, or 100% level of activity of the parent polypeptide. In other words, a functional variant of a polypeptide or encoded polypeptide of this disclosure has “similar binding,” “similar affinity” or “similar activity” when the functional variant displays no more than a 50% reduction in performance in a selected assay as compared to the parent or reference polypeptide, such as an assay for measuring binding affinity (e.g., Biacore® or tetramer staining measuring an association (Ka) or a dissociation (KD) constant). As used herein, a “functional portion” or “functional fragment” refers to a polypeptide or polynucleotide that comprises only a domain, portion or fragment of a parent or reference compound, and the polypeptide or encoded polypeptide retains at least 50% activity associated with the domain, portion or fragment of the parent or reference compound, preferably at least 55%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, 99.9%, or 100% level of activity of the parent polypeptide, or provides a biological benefit (e.g., effector function). A “functional portion” or “functional fragment” of a polypeptide or encoded polypeptide of this disclosure has “similar binding” or “similar activity” when the functional portion or fragment displays no more than a 50% reduction in performance in a selected assay as compared to the parent or reference polypeptide (preferably no more than 20% or 10%, or no more than a log difference as compared to the parent or reference with regard to affinity). As used herein, the term “engineered,” “recombinant,” or “non-natural” refers to an organism, microorganism, cell, nucleic acid molecule, or vector that includes at least one genetic alteration or has been modified by introduction of an exogenous or heterologous nucleic acid molecule, wherein such alterations or modifications are introduced by genetic engineering (i.e., human intervention). Genetic alterations include, for example, modifications introducing expressible nucleic acid molecules encoding functional RNA, proteins, fusion proteins or enzymes, or other nucleic acid molecule additions, deletions, substitutions, or other functional disruption of a cell’s genetic material. Additional modifications include, for example, non-coding regulatory regions in which the modifications alter expression of a polynucleotide, gene, or operon. As used herein, “heterologous” or “non-endogenous” or “exogenous” refers to any gene, protein, compound, nucleic acid molecule, or activity that is not native to a host cell or a subject, or any gene, protein, compound, nucleic acid molecule, or activity native to a host cell or a subject that has been altered. Heterologous, non-endogenous, or exogenous includes genes, proteins, compounds, or nucleic acid molecules that have been mutated or otherwise altered such that the structure, activity, or both is different as between the native and altered genes, proteins, compounds, or nucleic acid molecules. In certain embodiments, heterologous, non-endogenous, or exogenous genes, proteins, or nucleic acid molecules (e.g., receptors, ligands, etc.) may not be endogenous to a host cell or a subject, but instead nucleic acids encoding such genes, proteins, or nucleic acid molecules may have been added to a host cell by conjugation, transformation, transfection, electroporation, or the like, wherein the added nucleic acid molecule may integrate into a host cell genome or can exist as extra-chromosomal genetic material (e.g., as a plasmid or other self-replicating vector). The term “homologous” or “homolog” refers to a gene, protein, compound, nucleic acid molecule, or activity found in or derived from a host cell, species, or strain. For example, a heterologous or exogenous polynucleotide or gene encoding a polypeptide may be homologous to a native polynucleotide or gene and encode a homologous polypeptide or activity, but the polynucleotide or polypeptide may have an altered structure, sequence, expression level, or any combination thereof. A non-endogenous polynucleotide or gene, as well as the encoded polypeptide or activity, may be from the same species, a different species, or a combination thereof. In certain embodiments, a nucleic acid molecule or portion thereof native to a host cell will be considered heterologous to the host cell if it has been altered or mutated, or a nucleic acid molecule native to a host cell may be considered heterologous if it has been altered with a heterologous expression control sequence or has been altered with an endogenous expression control sequence not normally associated with the nucleic acid molecule native to a host cell. In addition, the term “heterologous” can refer to a biological activity that is different, altered, or not endogenous to a host cell. As described herein, more than one heterologous nucleic acid molecule can be introduced into a host cell as separate nucleic acid molecules, as a plurality of individually controlled genes, as a polycistronic nucleic acid molecule, as a single nucleic acid molecule encoding a fusion protein, or any combination thereof. As used herein, the term “endogenous” or “native” refers to a polynucleotide, gene, protein, compound, molecule, or activity that is normally present in a host cell or a subject. The term “expression”, as used herein, refers to the process by which a polypeptide is produced based on the encoding sequence of a nucleic acid molecule, such as a gene. The process may include transcription, post-transcriptional control, post-transcriptional modification, translation, post-translational control, post- translational modification, or any combination thereof. An expressed nucleic acid molecule is typically operably linked to an expression control sequence (e.g., a promoter). The term “operably linked” refers to the association of two or more nucleic acid molecules on a single nucleic acid fragment so that the function of one is affected by the other. For example, a promoter is operably linked with a coding sequence when it is capable of affecting the expression of that coding sequence (i.e., the coding sequence is under the transcriptional control of the promoter). “Unlinked” means that the associated genetic elements are not closely associated with one another and the function of one does not affect the other. As described herein, more than one heterologous nucleic acid molecule can be introduced into a host cell as separate nucleic acid molecules, as a plurality of individually controlled genes, as a polycistronic nucleic acid molecule, as a single nucleic acid molecule encoding a protein (e.g., a heavy chain of an antibody), or any combination thereof. When two or more heterologous nucleic acid molecules are introduced into a host cell, it is understood that the two or more heterologous nucleic acid molecules can be introduced as a single nucleic acid molecule (e.g., on a single vector), on separate vectors, integrated into the host chromosome at a single site or multiple sites, or any combination thereof. The number of referenced heterologous nucleic acid molecules or protein activities refers to the number of encoding nucleic acid molecules or the number of protein activities, not the number of separate nucleic acid molecules introduced into a host cell. The term “construct” refers to any polynucleotide that contains a recombinant nucleic acid molecule (or, when the context clearly indicates, a fusion protein of the present disclosure). A (polynucleotide) construct may be present in a vector (e.g., a bacterial vector, a viral vector) or may be integrated into a genome. A “vector” is a nucleic acid molecule that is capable of transporting another nucleic acid molecule. Vectors may be, for example, plasmids, cosmids, viruses, a RNA vector or a linear or circular DNA or RNA molecule that may include chromosomal, non-chromosomal, semi-synthetic or synthetic nucleic acid molecules. Vectors of the present disclosure also include transposon systems (e.g., Sleeping Beauty, see, e.g., Geurts et al., Mol. Ther.8:108, 2003: Mátés et al., Nat. Genet.41:753, 2009). Exemplary vectors are those capable of autonomous replication (episomal vector), capable of delivering a polynucleotide to a cell genome (e.g., viral vector), or capable of expressing nucleic acid molecules to which they are linked (expression vectors). As used herein, “expression vector” or “vector” refers to a DNA construct containing a nucleic acid molecule that is operably linked to a suitable control sequence capable of effecting the expression of the nucleic acid molecule in a suitable host. Such control sequences include a promoter to effect transcription, an optional operator sequence to control such transcription, a sequence encoding suitable mRNA ribosome binding sites, and sequences which control termination of transcription and translation. The vector may be a plasmid, a phage particle, a virus, or simply a potential genomic insert. Once transformed into a suitable host, the vector may replicate and function independently of the host genome, or may, in some instances, integrate into the genome itself or deliver the polynucleotide contained in the vector into the genome without the vector sequence. In the present specification, “plasmid,” “expression plasmid,” “virus,” and “vector” are often used interchangeably. The term “introduced” in the context of inserting a nucleic acid molecule into a cell, means “transfection”, “transformation,” or “transduction” and includes reference to the incorporation of a nucleic acid molecule into a eukaryotic or prokaryotic cell wherein the nucleic acid molecule may be incorporated into the genome of a cell (e.g., chromosome, plasmid, plastid, or mitochondrial DNA), converted into an autonomous replicon, or transiently expressed (e.g., transfected mRNA). In certain embodiments, polynucleotides of the present disclosure may be operatively linked to certain elements of a vector. For example, polynucleotide sequences that are needed to effect the expression and processing of coding sequences to which they are ligated may be operatively linked. Expression control sequences may include appropriate transcription initiation, termination, promoter, and enhancer sequences; efficient RNA processing signals such as splicing and polyadenylation signals; sequences that stabilize cytoplasmic mRNA; sequences that enhance translation efficiency (i.e., Kozak consensus sequences); sequences that enhance protein stability; and possibly sequences that enhance protein secretion. Expression control sequences may be operatively linked if they are contiguous with the gene of interest and expression control sequences that act in trans or at a distance to control the gene of interest. In certain embodiments, the vector comprises a plasmid vector or a viral vector (e.g., a lentiviral vector or a γ-retroviral vector). Viral vectors include retrovirus, adenovirus, parvovirus (e.g., adeno-associated viruses), coronavirus, negative strand RNA viruses such as ortho-myxovirus (e.g., influenza virus), rhabdovirus (e.g., rabies and vesicular stomatitis virus), paramyxovirus (e.g., measles and Sendai), positive strand RNA viruses such as picornavirus and alphavirus, and double-stranded DNA viruses including adenovirus, herpesvirus (e.g., Herpes Simplex virus types 1 and 2, Epstein-Barr virus, cytomegalovirus), and poxvirus (e.g., vaccinia, fowlpox, and canarypox). Other viruses include, for example, Norwalk virus, togavirus, flavivirus, reoviruses, papovavirus, hepadnavirus, and hepatitis virus. Examples of retroviruses include avian leukosis-sarcoma, mammalian C-type, B-type viruses, D type viruses, HTLV-BLV group, lentivirus, spumavirus (Coffin, J. M., Retroviridae: The viruses and their replication, In Fundamental Virology, Third Edition, B. N. Fields et al., Eds., Lippincott-Raven Publishers, Philadelphia, 1996). “Retroviruses” are viruses having an RNA genome, which is reverse-transcribed into DNA using a reverse transcriptase enzyme, the reverse-transcribed DNA is then incorporated into the host cell genome. “Gammaretrovirus” refers to a genus of the retroviridae family. Examples of gammaretroviruses include mouse stem cell virus, murine leukemia virus, feline leukemia virus, feline sarcoma virus, and avian reticuloendotheliosis viruses. “Lentiviral vectors” include HIV-based lentiviral vectors for gene delivery, which can be integrative or non-integrative, have relatively large packaging capacity, and can transduce a range of different cell types. Lentiviral vectors are usually generated following transient transfection of three (packaging, envelope, and transfer) or more plasmids into producer cells. Like HIV, lentiviral vectors enter the target cell through the interaction of viral surface glycoproteins with receptors on the cell surface. On entry, the viral RNA undergoes reverse transcription, which is mediated by the viral reverse transcriptase complex. The product of reverse transcription is a double-stranded linear viral DNA, which is the substrate for viral integration into the DNA of infected cells. In certain embodiments, the viral vector can be a gammaretrovirus, e.g., Moloney murine leukemia virus (MLV)-derived vectors. In other embodiments, the viral vector can be a more complex retrovirus-derived vector, e.g., a lentivirus-derived vector. HIV-1-derived vectors belong to this category. Other examples include lentivirus vectors derived from HIV-2, FIV, equine infectious anemia virus, SIV, and Maedi-Visna virus (ovine lentivirus). Methods of using retroviral and lentiviral viral vectors and packaging cells for transducing mammalian host cells with viral particles containing transgenes are known in the art and have been previous described, for example, in: U.S. Patent 8,119,772; Walchli et al., PLoS One 6:327930, 2011; Zhao et al., J. Immunol.174:4415, 2005; Engels et al., Hum. Gene Ther.14:1155, 2003; Frecha et al., Mol. Ther.18:1748, 2010; and Verhoeyen et al., Methods Mol. Biol.506:97, 2009. Retroviral and lentiviral vector constructs and expression systems are also commercially available. Other viral vectors also can be used for polynucleotide delivery including DNA viral vectors, including, for example adenovirus-based vectors and adeno-associated virus (AAV)-based vectors; vectors derived from herpes simplex viruses (HSVs), including amplicon vectors, replication-defective HSV and attenuated HSV (Krisky et al., Gene Ther.5:1517, 1998). Other vectors that can be used with the compositions and methods of this disclosure include those derived from baculoviruses and α-viruses. (Jolly, D J.1999. Emerging Viral Vectors. pp 209-40 in Friedmann T. ed. The Development of Human Gene Therapy. New York: Cold Spring Harbor Lab), or plasmid vectors (such as sleeping beauty or other transposon vectors). When a viral vector genome comprises a plurality of polynucleotides to be expressed in a host cell as separate transcripts, the viral vector may also comprise additional sequences between the two (or more) transcripts allowing for bicistronic or multicistronic expression. Examples of such sequences used in viral vectors include internal ribosome entry sites (IRES), furin cleavage sites, viral 2A peptide, or any combination thereof. Plasmid vectors, including DNA-based antibody or antigen-binding fragment- encoding plasmid vectors for direct administration to a subject, are described further herein. As used herein, the term “host” refers to a cell or microorganism targeted for genetic modification with a heterologous nucleic acid molecule to produce a polypeptide of interest (e.g., an antibody of the present disclosure). A host cell may include any individual cell or cell culture which may receive a vector or the incorporation of nucleic acids or express proteins. The term also encompasses progeny of the host cell, whether genetically or phenotypically the same or different. Suitable host cells may depend on the vector and may include mammalian cells, animal cells, human cells, simian cells, insect cells, yeast cells, and bacterial cells. These cells may be induced to incorporate the vector or other material by use of a viral vector, transformation via calcium phosphate precipitation, DEAE-dextran, electroporation, microinjection, or other methods. See, for example, Sambrook et al., Molecular Cloning: A Laboratory Manual 2d ed. (Cold Spring Harbor Laboratory, 1989). In the context of a SARS-CoV-2 infection (or infection by another sarbecovirus), a “host” refers to a cell or a subject infected with the SARS-CoV-2 coronavirus (or other sarbecovirus). “Antigen” or “Ag”, as used herein, refers to an immunogenic molecule that provokes an immune response. This immune response may involve antibody production, activation of specific immunologically-competent cells, activation of complement, antibody dependent cytotoxicicity, or any combination thereof. An antigen (immunogenic molecule) may be, for example, a peptide, glycopeptide, polypeptide, glycopolypeptide, polynucleotide, polysaccharide, lipid, or the like. It is readily apparent that an antigen can be synthesized, produced recombinantly, or derived from a biological sample. Exemplary biological samples that can contain one or more antigens include tissue samples, stool samples, cells, biological fluids, or combinations thereof. Antigens can be produced by cells that have been modified or genetically engineered to express an antigen. Antigens can also be present in a sarbecovirus, e.g. SARS-CoV-2 coronavirus (e.g., a surface glycoprotein or portion thereof), such as present in a virion, or expressed or presented on the surface of a cell infected by SARS- CoV-2. The term “epitope” or “antigenic epitope” includes any molecule, structure, amino acid sequence, or protein determinant that is recognized and specifically bound by a cognate binding molecule, such as an immunoglobulin, or other binding molecule, domain, or protein. Epitopic determinants generally contain chemically active surface groupings of molecules, such as amino acids or sugar side chains, and can have specific three-dimensional structural characteristics, as well as specific charge characteristics. Where an antigen is or comprises a peptide or protein, the epitope can be comprised of consecutive amino acids (e.g., a linear epitope), or can be comprised of amino acids from different parts or regions of the protein that are brought into proximity by protein folding (e.g., a discontinuous or conformational epitope), or non-contiguous amino acids that are in close proximity irrespective of protein folding. Antibodies, Antigen-Binding Fragments, and Compositions In one aspect, the present disclosure provides an (e.g. isolated) anti-SARS-CoV- 2 antibody, or an antigen-binding fragment thereof. In some embodiments, the anti- SARS-CoV-2 antibody or antigen-binding fragment is capable of binding to a surface glycoprotein of a sarbecovirus. It will be understood that “anti-SARS-CoV-2 antibody” refers to an antibody that is capable of binding to a SARS-CoV-2 antigen (e.g., a surface glycoprotein, a RBD), though, as provided herein, certain embodiments provide antibodies and antigen-binding fragments that are capable of binding to SARS-CoV-2 (e.g., Wuhan-Hu-1 and one or more other SARS-CoV-2 strains or variants) and/or to one or more other sarbecoviruses. In certain embodiments, the antibody or antigen-binding fragment is capable of binding to a sarbecovirus of clade 1a, clade 1b, clade 2, and/or clade 3. In certain embodiments, the antibody or antigen-binding fragment is capable of binding to a surface glycoprotein of any one or more of SARS-CoV-2 (e.g., Wuhan-Hu-1), SARS- CoV-2 G504D (optionally Wuhan-Hu-1 comprising G504D, BA.5 comprising D504G, or both), SARS-CoV-2 delta variant, SARS-CoV-2 omicron variant, SARS-CoV-2 BA.2, SARS-CoV-2 BA.5, SARS-CoV-2 BA.4-5 (also written as SARS-CoV-2 BA.4/5), SARS-CoV-2 BA.4, SARS-CoV-2 BA.4.6, ZC45, BGR08, and SARS-CoV (also referred-to as a SARS-CoV-1). In certain embodiments, an antibody or antigen-binding fragment of the present disclosure associates with or unites with a coronavirus (e.g. SARS-CoV-2) surface glycoprotein epitope or antigen comprising the epitope, while not significantly associating or uniting with any other molecules or components in a sample. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure associates with or unites (e.g., binds) to a SARS-CoV-2 surface glycoprotein epitope, and can also associate with or unite with an epitope from another coronavirus (e.g., SARS-CoV) present in the sample, but not significantly associating or uniting with any other molecules or components in the sample. In other words, in certain embodiments, an antibody or antigen binding fragment of the present disclosure is cross-reactive for SARS-CoV-2 and one or more additional coronavirus. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure is capable of binding to a surface glycoprotein of two or more sarbecoviruses. In some embodiments, the two or more sarbecoviruses are selected from: clade 1a sarbecoviruses and/or clade 1b sarbecoviruses; clade 2 sarbecoviruses; clade 3 sarbecoviruses; or naturally occuring variants thereof, and any combination thereof. In certain embodiments, the antibody or antigen-binding fragment is capable of binding to a surface glycoprotein of two or more sarbecoviruses; e.g., capable of binding when a sarbecovirus S protein is expressed on a cell surface of a host cell and/or on a sarbecovirus virion. In certain embodiments, the two or more sarbecoviruses are selected from SARS-CoV, WIV1, SARS-CoV2, SARS-CoV-2 G504D, Anlong112, YN2013, SX2011, SC2018, PANG/GD, PANG/GX, RatG13, ZXC21, ZC45, RmYN02, BGR2008 (aka BGR08), BtkY72, and naturally occurring variants thereof. In some embodiments, the two or more sarbecoviruses include one or more of SARS-CoV-2 variants P.1, B.1.1.7, B.1.429, B.1.351, B.1.617.2, BA.2, BA.4, BA.5, BA.4/5, and BA.4.6. In some embodiments, the two or more sarbecoviruses include one or more SARS-CoV-2 variants having S protein mutations N501Y, Y453F, N439K, K417V, E484K, or any combination thereof. In some embodiments, an antibody or antigen-binding fragment is capable of binding to a SARS-CoV-2 G504D variant. In some embodiments, an antibody or antigen-binding fragment is capable of binding to a SARS-CoV-2 B.1.617.2. In some embodiments, an antibody or antigen- binding fragment is capable of binding to a SARS-CoV (also referred-to as a SARS- CoV-1). In certain embodiments, an antibody or antigen-binding fragment of the present disclosure associates with or unites with a sarbecovirus surface glycoprotein epitope or antigen comprising the epitope, while not significantly associating or uniting with any other molecules or components in a sample. In some embodiments, the epitope is comprised in a S1 subunit of a spike (S) protein. In further embodiments, the epitope is comprised in a receptor binding domain (RBD) of a S protein. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure associates with or unites (e.g., binds) to a first sarbecovirus surface glycoprotein epitope, and can also associate with or unite with an epitope from another sarbecovirus present in the sample, but not significantly associating or uniting with any other molecules or components in the sample. In other words, in certain embodiments, an antibody or antigen binding fragment of the present disclosure is cross-reactive against and specifically binds to two or more sarbecoviruses. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure specifically binds to a sarbecovirus surface glycoprotein, such as a SARS- CoV-2 surface glycoprotein. As used herein, “specifically binds” refers to an association or union of an antibody or antigen-binding fragment to an antigen with an affinity or K _a (i.e., an equilibrium association constant of a particular binding interaction with units of 1/M) equal to or greater than 10 ⁵ M ^-1 (which equals the ratio of the on-rate [Kon] to the off rate [Koff] for this association reaction), while not significantly associating or uniting with any other molecules or components in a sample. Alternatively, affinity may be defined as an equilibrium dissociation constant (Kd) of a particular binding interaction with units of M (e.g., 10 ^-5 M to 10 ^-13 M). Antibodies may be classified as “high-affinity” antibodies or as “low-affinity” antibodies. “High-affinity” antibodies refer to those antibodies having a Ka of at least 10 ⁷ M ^-1 , at least 10 ⁸ M ^-1 , at least 10 ⁹ M ^-1 , at least 10 ¹⁰ M ^-1 , at least 10 ¹¹ M ^-1 , at least 10 ¹² M ^-1 , or at least 10 ¹³ M ^-1 . “Low-affinity” antibodies refer to those antibodies having a K _a of up to 10 ⁷ M ^-1 , up to 10 ⁶ M ^-1 , up to 10 ⁵ M ^-1 . Alternatively, affinity may be defined as an equilibrium dissociation constant (Kd) of a particular binding interaction with units of M (e.g., 10 ^-5 M to 10 ^-13 M). In some contexts, antibody and antigen-binding fragments may be described with reference to affinity and/or to avidity for antigen. Unless otherwise indicated, avidity refers to the total binding strength of an antibody or antigen-binding fragment thereof to antigen, and reflects binding affinity, valency of the antibody or antigen- binding fragment (e.g., whether the antibody or antigen-binding fragment comprises one, two, three, four, five, six, seven, eight, nine, ten, or more binding sites), and, for example, whether another agent is present that can affect the binding (e.g., a non- competitive inhibitor of the antibody or antigen-binding fragment). A variety of assays are known for identifying antibodies of the present disclosure that bind a particular target, as well as determining binding domain or binding protein affinities, such as Western blot, ELISA (e.g., direct, indirect, or sandwich), analytical ultracentrifugation, spectroscopy, and surface plasmon resonance (Biacore®) analysis (see, e.g., Scatchard et al., Ann. N.Y. Acad. Sci.51:660, 1949; Wilson, Science 295:2103, 2002; Wolff et al., Cancer Res.53:2560, 1993; and U.S. Patent Nos.5,283,173, 5,468,614, or the equivalent). Assays for assessing affinity or apparent affinity or relative affinity are also known. In certain examples, binding can be determined by recombinantly expressing a sarbecovirus antigen, such as a SARS-CoV-2 antigen in a host cell (e.g., by transfection) and immunostaining the (e.g., fixed, or fixed and permeabilized) host cell with antibody and analyzing binding by flow cytometery (e.g., using a ZE5 Cell Analyzer (BioRad®) and FlowJo software (TreeStar). In some embodiments, positive binding can be defined by differential staining by antibody of SARS-CoV-2 -expressing cells versus control (e.g., mock) cells. In some embodiments, an antibody or antigen-binding fragment of the present disclosure binds to a sarbecovirus spike protein (i.e., from two or more sarbecoviruses) expressed on the surface of a host cell (e.g., an Expi-CHO cell), as determined by flow cytometry. In some embodiments an antibody or antigen-binding fragment of the present disclosure binds to a sarbecovirus S protein, such as a SARS-CoV-2 S protein, as measured using biolayer interferometry. In certain embodiments, an antibody of the present disclosure is capable of neutralizing infection by a sarbecovirus, such as, e.g., SARS-CoV-2, SARS-CoV, SARS-CoV-2 delta variant, and/or SARS-CoV-2 G504D variant. In certain embodiments, an antibody of the present disclosure is capable of neutralizing infection by two or more sarbecoviruses. As used herein, a “neutralizing antibody” is one that can neutralize, i.e., prevent, inhibit, reduce, impede, or interfere with, the ability of a pathogen to initiate and/or perpetuate an infection in a host. The terms “neutralizing antibody” and “an antibody that neutralizes” or “antibodies that neutralize” are used interchangeably herein. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment is capable of preventing and/or neutralizing a SARS-CoV-2 infection (and/or infection by another sarbecovirus) in an in vitro model of infection and/or in an in vivo animal model of infection and/or in a human. In some embodiments, an antibody or antigen-binding fragment is capable of neutralizing an infection by a clade 1 (e.g. clade 1a, clade 1b, or both) sarbecovirus, a clade 2 sarbecovirus, a clade 3 sarbecovirus, or any combination thereof. In some embodiments, an antibody or antigen-binding fragment is capable of neutralizing an infection by any one or more, any two or more, any three or more, any four or more, any five or more, any six or more, any seven or more, any eight or more, any nine or more, any ten or more, any eleven or more, or all twelve of: a SARS-CoV-2 Wuhan- Hu-1; a SARS-CoV-2 G504D; a SARS-CoV; a SARS-CoV-2 delta variant, a SARS- CoV-2 omicron variant; a SARS-CoV-2 BA.2; a SARS-CoV-2 BA.4; a SARS-CoV-2 BA.4/5; a SARS-CoV-2 BA.5; a SARS-CoV-2 BA.4.6; a BGR08; and a ZC45. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment is capable of preventing and/or neutralizing a sarbecovirus (e.g. SARS-CoV-2, SARS- CoV-2 variant, SARS-CoV, ZC45, BGR08) infection in an in vitro model of infection and/or in an in vivo animal model of infection and/or in a human. Terms understood by those in the art of antibody technology are each given the meaning acquired in the art, unless expressly defined differently herein. For example, the term “antibody” refers to an intact antibody comprising at least two heavy (H) chains and two light (L) chains inter-connected by disulfide bonds, as well as any antigen-binding portion or fragment of an intact antibody that has or retains the ability to bind to the antigen target molecule recognized by the intact antibody, such as an scFv, Fab, or Fabʹ2 fragment. Thus, the term “antibody” herein is used in the broadest sense and includes polyclonal and monoclonal antibodies, including intact antibodies and functional (antigen-binding) antibody fragments thereof, including fragment antigen binding (Fab) fragments, F(abʹ)2 fragments, Fabʹ fragments, Fv fragments, recombinant IgG (rIgG) fragments, single chain antibody fragments, including single chain variable fragments (scFv), and single domain antibodies (e.g., sdAb, sdFv, nanobody) fragments. The term encompasses genetically engineered and/or otherwise modified forms of immunoglobulins, such as intrabodies, peptibodies, chimeric antibodies, fully human antibodies, humanized antibodies, and heteroconjugate antibodies, multispecific, e.g., bispecific antibodies, diabodies, triabodies, tetrabodies, tandem di-scFv, and tandem tri-scFv. Unless otherwise stated, the term “antibody” should be understood to encompass functional antibody fragments thereof. The term also encompasses intact or full-length antibodies, including antibodies of any class or sub-class, including IgG and sub-classes thereof (IgG1 (e.g., IgG1m, 17), IgG2, IgG3, IgG4), IgM, IgE, IgA, and IgD. The terms “V _L ” or “VL” and “V _H ” or “VH” refer to the variable binding region (also referred to as variable domain or variable binding domain) from an antibody light chain and an antibody heavy chain, respectively. In certain embodiments, a VL is a kappa (κ) class (also “VK” herein). In certain embodiments, a VL is a lambda (λ) class. The variable binding regions comprise discrete, well-defined sub-regions known as “complementarity determining regions” (CDRs) and “framework regions” (FRs). The terms “complementarity determining region,” and “CDR,” are synonymous with “hypervariable region” or “HVR,” and refer to sequences of amino acids within antibody variable regions, which, in general, together confer the antigen specificity and/or binding affinity of the antibody, wherein consecutive CDRs (i.e., CDR1 and CDR2, CDR2 and CDR3) are separated from one another in primary structure by a framework region. There are three CDRs in each variable region (HCDR1, HCDR2, HCDR3; LCDR1, LCDR2, LCDR3; also referred to as CDRHs and CDRLs, respectively). In certain embodiments, an antibody VH comprises four FRs and three CDRs as follows: FR1-HCDR1-FR2-HCDR2-FR3-HCDR3-FR4; and an antibody VL comprises four FRs and three CDRs as follows: FR1-LCDR1-FR2-LCDR2-FR3- LCDR3-FR4. In general, the VH and the VL together form the antigen-binding site through their respective CDRs. As used herein, a “variant” of a CDR refers to a functional variant of a CDR sequence having up to 1-3 amino acid substitutions (e.g., conservative or non- conservative substitutions), deletions, or combinations thereof. Numbering of CDR and framework regions may be according to any known method or scheme, such as the Kabat, Chothia, EU, IMGT, and AHo numbering schemes (see, e.g., Kabat et al., “Sequences of Proteins of Immunological Interest,” US Dept. Health and Human Services, Public Health Service National Institutes of Health, 1991, 5 ^th ed.; Chothia and Lesk, J. Mol. Biol.196:901-917 (1987)); Lefranc et al., Dev. Comp. Immunol.27:55, 2003; Honegger and Plückthun, J. Mol. Bio.309:657-670 (2001)). Other CDR numbering schemes include North (described in “A New Clustering of Antibody CDR Loop Conformations”, Journal of Molecular Biology, 406, 228-256 (2011)), AbM, and Martin (also referred to as Enhanced Chothia). Equivalent residue positions can be annotated and for different molecules to be compared using Antigen receptor Numbering And Receptor Classification (ANARCI) software tool (2016, Bioinformatics 15:298-300). Also for IMGT numbering, a variable domain (or variable domain-containing) amino acid sequence of interest can be annotated using IMGT V-QUEST (www.imgt.org/IMGT_vquest/analysis; see also Brochet et al. Nucl. Acids Res.36 W503-508, doi:10.1093/nar/gkn316 (2008)). Accordingly, identification of CDRs of a variable domain (VH or VL) sequence as provided herein according to one numbering scheme is not exclusive of an antibody comprising CDRs of the same variable domain as determined using a different numbering scheme. In some embodiments, CDRs of a variable domain or region (VH or VL) sequence as provided herein are a combination of any two or more of the following numbering schemes: Kabat, Chothia, IMGT, CCG, AHo, AbM, Martin, North, and EU. In certain embodiments, an antibody or an antigen-binding fragment of the present disclosure comprises a CDRH1, a CDRH2, a CDRH3, a CDRL1, a CDRL2, and a CDRL3, wherein each CDR is independently selected from a corresponding CDR of an antibody having a VH and/or a VL as set forth in Table 1 or Table 2. In particular embodiments, an antibody or antigen-binding fragment comprises a CDRH1, a CDRH2, a CDRH3, a CDRL1, a CDRL2, and a CDRL3 selected from any of the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 amino acid sequences (respectively) of an antibody as provided in Table 1 or Table 2. In some embodiments, an antibody or antigen-binding fragment comprises: a CDRH1, a CDRH2, and/or a CDRH3 of a VH amino acid sequence as set forth in Table 1 or Table 2, and/or a CDRL1, a CDRL2, and/or a CDRL3 of a VL amino acid sequence as set forth in Table 1 or Table 2 (i.e., according to any CDR numbering or determination method known in the art, such as IMGT, Kabat, Chothia, AHo, North, Contact, CCG, EU, AbM, or Martin (Enhanced Chothia)). In some embodiments, the antibody or antigen-binding fragment comprises, in a VH, the amino acid sequences GGIDNTYT (SEQ ID NO.:138), ILMSGWA (SEQ ID NO.:136), and ARGFHSDYYGWGDDDAFDF (SEQ ID NO.:137), and in a VL, the amino acid sequences NSNIGAGYD (SEQ ID NO.:43), GNS (SEQ ID NO.:44), and QSYDSSLSEPTWV (SEQ ID NO.:139). In further embodments, the antibody or antigen-binding fragment comprises a VH having at least 85% identity (i.e., 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%, or any non-integer percentage therein, such as, for example, 90.2%) identity to a VH amino acid sequence provided in Table 1 or Table 2, and/or a VL having at least 85% identity (i.e., at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%, or any non-integer percentage therein, such as, for example, 90.2%) identity to a VL amino acid sequence provided in Table 1 or Table 2. In still further embodments, the antibody or antigen-binding fragment comprises a VH having at least 90% identity identity to a VH amino acid sequence provided in Table 1 or Table 2, and/or a VL having at least 90% identity to a VL amino acid sequence provided in Table 1 or Table 2. In still further embodments, the antibody or antigen-binding fragment comprises a VH having at least 95% identity identity to a VH amino acid sequence provided in Table 1 or Table 2, and/or a VL having at least 95% identity to a VL amino acid sequence provided in Table 1 or Table 2. In still further embodments, the antibody or antigen-binding fragment comprises a VH having at least 99% identity identity to a VH amino acid sequence provided in Table 1 or Table 2, and/or a VL having at least 99% identity to a VL amino acid sequence provided in Table 1 or Table 2. In some embodiments, the antibody or antigen-binding fragment comprises a VH amino acid sequence selected from the VH amino acid sequences provided in Table 1 or Table 2, and a VL amino acid sequence selected from the VL amino acid sequences provided in Table 1 or Table 2. Table 1. Variable Region Amino Acid and Polynucleotide SEQ ID NOs. of Certain Antibodies of the Present Disclosure. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and/or a CDRH3 of the VH amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, and 98, and/or a CDRL1, a CDRL2, and/or a CDRL3 of the VL amino acid sequence set forth in any one of SEQ ID NOs.:72, 76, 80, 84, 88, 92, 96, and 100. CDRs of a variable domain can be determined according to any CDR numbering or determination method known in the art, such as, for example, IMGT, Kabat, Chothia, AHo, North, Contact, CCG, EU, AbM, or Martin (Enhanced Chothia)). In certain embodiments, the CDRH1, CDRH2, and/or CDRH3, and/or the CDRL1, CDRL2, and CDRL3 are according to IMGT numbering, Kabat numbering, Chothia numbering, AHo numbering, North numbering, Contact numbering, CCG numbering, EU numbering, AbM numbering, or Martin (Enhanced Chothia) numbering. In some embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to a hybrid definition of two or more of the foregoing numbering systems.In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, and 98, and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in any one of SEQ ID NOs.:72, 76, 80, 84, 88, 92, 96, and 100. In certain embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to IMGT numbering, Kabat numbering, Chothia numbering, AHo numbering, North numbering, Contact numbering, CCG numbering, EU numbering, or Martin (Enhanced Chothia) numbering. In some embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to a hybrid definition of two or more of the foregoing numbering systems. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:70 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:74 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, an antibody or antigen- binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:78 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:82 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:86 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:90 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:94 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:98 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:100. In certain embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to IMGT numbering, Kabat numbering, Chothia numbering, AHo numbering, North numbering, Contact numbering, CCG numbering, EU numbering, AbM numbering, or Martin (Enhanced Chothia) numbering. In some embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to a hybrid definition of two or more of the foregoing numbering systems. Table 2. Variable Region Amino Acid SEQ ID NOs. of Certain Other Antibodies of the Present Disclosure. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:101 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, an antibody or antigen- binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:109 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:116 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:120 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:130 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:131 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:131 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:133 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, an antibody or antigen-binding fragment is provided that comprises a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:135 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113. In certain embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to IMGT numbering, Kabat numbering, Chothia numbering, AHo numbering, North numbering, Contact numbering, CCG numbering, EU numbering, AbM numbering, or Martin (Enhanced Chothia) numbering. In some embodiments, the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 are according to a hybrid definition of two or more of the foregoing numbering systems. In some embodiments, the antibody or antigen-binding fragment comprises, in a VH, the amino acid sequences GGIDNTYT (SEQ ID NO.:138), ILMSGWA (SEQ ID NO.:136), and ARGFHSDYYGWGDDDAFDF (SEQ ID NO.:437), and in a VL, the amino acid sequences NSNIGAGYD (SEQ ID NO.:43), GNS (SEQ ID NO.:44), and QSYDSSLSEPTWV (SEQ ID NO.:139). In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% (e.g., 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%) identity to the amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, 98, 101, 109, 116, 120, 130, 131, and 133, and the VL comprises or consists of an amino acid sequence having at least 85% (e.g., 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%) identity to the amino acid sequence set forth in any one of SEQ ID NOs.::72, 76, 80, 84, 88, 92, 96, 100, 105, 113, 118, 124, 132, and 134. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:72. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:76. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:80. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:84. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:88. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:92. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:96. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:100. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:100. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:100. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:100. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:100. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:118. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:124. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:105. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:132. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:133 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:133 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:133 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:133 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:133 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:134. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113. In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIFNTYTISWVRQAPGQGLEWMG RIILMSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NSNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:70); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSFDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:72). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN GNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:74); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:76). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILTSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGY NGNYYGWGDDDAFDNWGQGTLVTVSS (SEQ ID NO.:78); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRRSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSGPNW VFGGGTKLTVL (SEQ ID NO.:80). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGSHNTYTISWVRQAPGQGLEWMG RIILMSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:82); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPQWV FGGGTKLTVL (SEQ ID NO.:84). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILSSGLANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN GNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:86); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCNGSNSNIGVGYDVHWYQQLPGTAPKLLIV GNSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSGPNW VFGGGTKLTVL (SEQ ID NO.:88). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGILNTYTISWVRQAPGQGLEWMG RIILRSGMTNYAQNIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDNWGQGTLVTVSS (SEQ ID NO.:90); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCNGSNSNIGVGYDVHWYQQLPGTAPKLLIV GNSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSGPNW VFGGGTKLTVL (SEQ ID NO.:92). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILMSGSANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:94); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSDPNW VFGGGTKLTVL (SEQ ID NO.:96). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIFNTYTISWVRQAPGQGLEWMG RIILNSGFANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFS GRYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:98) ; and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGTNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRASGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSDPIWV FGGGTKLTVL (SEQ ID NO.:100). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:101) ; and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:105). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILMSGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NSNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:109) ; and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (iii) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:116) ; and (iv) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:76). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILSSGLANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:120) ; and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGVGYDVHWYQQLPGTAPKLLIV GQSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSGPNW VFGGGTKLTVL (SEQ ID NO.:124). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGFGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:130); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:105). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN SNYYGFGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:131); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN SNYYGFGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:131); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:132). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: (i) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN SNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:133); and (ii) a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:132). In some embodiments, an antibody or antigen-binding fragment is provided that comprises: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILMSGWANYAQTIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF HSDYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:135); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). The term "CL" refers to an "immunoglobulin light chain constant region" or a "light chain constant region," i.e., a constant region from an antibody light chain. The term “CH” refers to an “immunoglobulin heavy chain constant region” or a “heavy chain constant region,” which is further divisible, depending on the antibody isotype into CH1, CH2, and CH3 (IgA, IgD, IgG), or CH1, CH2, CH3, and CH4 domains (IgE, IgM). The Fc region of an antibody heavy chain is described further herein. In any of the presently disclosed embodiments, an antibody or antigen-binding fragment of the present disclosure (e.g., one comprising the six CDRs, and optionally the VH and VL, of S2X259.774) comprises any one or more of CL, a CH1, a CH2, and a CH3. In certain embodiments, a CL comprises an amino acid sequence having 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to the amino acid sequence of SEQ ID NO.:7 or SEQ ID NO.:8. In certain embodiments, a CH1-CH2-CH3 (also referred-to as a CH1-CH3) comprises an amino acid sequence having 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to the amino acid sequence of SEQ ID NO.:6, SEQ ID NO.:7, SEQ ID NO.:127, SEQ ID NO.:128, or SEQ ID NO.:129. In some embodiments, an antibody or antigen-binding fragment comprises a CH1-CH3 of SEQ ID NO.:6, SEQ ID NO.:7, SEQ ID NO.:127, SEQ ID NO.:128, or SEQ ID NO.:129, and a CL of SEQ ID NO.:8. In some embodiments, an antibody or antigen-binding fragment of the present disclosure can comprise a heavy chain, a CH1- CH3, a CH3, or an Fc polypeptide wherein a C-terminal glycine-lysine sequence (e.g., corresponding to the last two amino acids of SEQ ID NO.:6, 7, 127, 128, or 129) is present or is absent. Antibodies and antigen-binding fragments of the disclosure may comprise a κ or a λ light chain. In some embodiments, the antibody is of IgG1 type and has a κ light chain. In some embodiments, the antibody is of IgG1 type and has a λ light chain. In some embodiments, an antibody or antigen-binding fragment can comprise a VH, a VL, a CH1-CH3, and a CL. The VH and the CH1-CH3 can together comprise a heavy chain and the VL and the CL can together comprise a light chain. Table A shows VH, CH1-CH3, VL, and CL amino acid sequences of certain embodiments of antibodies or antigen-binding fragments of the present disclosure. Table A. In certain other embodiments, an antibody or antigen-binding fragment comprising a combination of VH, VL, and CL amino acid sequences according to Table A can comprise a CH1-CH3 amino acid sequence according to SEQ ID NO.:7, SEQ ID NO.:127, SEQ ID NO.:128, or SEQ ID NO.:129. In certain other embodiments, an antibody or antigen-binding fragment comprising a combination of VH, VL, and CL amino acid sequences according to Table A can comprise a CH1-CH3 amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity to, or comprising or consisting of the amino acid sequence set forth in SEQ ID NO.:7, SEQ ID NO.:127, SEQ ID NO.:128, or SEQ ID NO.:129. In some embodiments, an antibody comprises two heavy chains and two light chains, wherein each of the two heavy chains comprises or consists of the same VH+CH1-CH3 amino acid sequence and each of the two light chains comprises or consists of the same VL+CL amino acid sequence. It will be understood that, for example, production in a mammalian cell line can remove one or more C-terminal lysine of an antibody heavy chain (see, e.g., Liu et al. mAbs 6(5):1145-1154 (2014)). Accordingly, an antibody or antigen-binding fragment of the present disclosure can comprise a heavy chain, a CH1-CH3, a CH3, or an Fc polypeptide wherein a C-terminal lysine residue is present or is absent; in other words, encompassed are embodiments where the C-terminal residue of a heavy chain, a CH1- CH3, or an Fc polypeptide is not a lysine, and embodiments where a lysine is the C- terminal residue. In certain embodiments, a composition comprises a plurality of an antibody and/or an antigen-binding fragment of the present disclosure, wherein one or more antibody or antigen-binding fragment does not comprise a lysine residue at the C- terminal end of the heavy chain, CH1-CH3, or Fc polypeptide, and wherein one or more antibody or antigen-binding fragment comprises a lysine residue at the C-terminal end of the heavy chain, CH1-CH3, or Fc polypeptide. A "Fab" (fragment antigen binding) is the part of an antibody that binds to antigens and includes the variable region and CH1 of the heavy chain linked to the light chain via an inter-chain disulfide bond. Each Fab fragment is monovalent with respect to antigen binding, i.e., it has a single antigen-binding site. Pepsin treatment of an antibody yields a single large F(abʹ)2 fragment that roughly corresponds to two disulfide linked Fab fragments having divalent antigen-binding activity and is still capable of cross-linking antigen. Both the Fab and F(abʹ)2 are examples of "antigen- binding fragments." Fabʹ fragments differ from Fab fragments by having additional few residues at the carboxy terminus of the CH1 domain including one or more cysteines from the antibody hinge region. Fabʹ-SH is the designation herein for Fabʹ in which the cysteine residue(s) of the constant domains bear a free thiol group. F(abʹ)2 antibody fragments originally were produced as pairs of Fabʹ fragments that have hinge cysteines between them. Other chemical couplings of antibody fragments are also known. Fab fragments may be joined, e.g., by a peptide linker, to form a single chain Fab, also referred to herein as "scFab". In these embodiments, an inter-chain disulfide bond that is present in a native Fab may not be present, and the linker serves in full or in part to link or connect the Fab fragments in a single polypeptide chain. A heavy chain- derived Fab fragment (e.g., comprising, consisting of, or consisting essentially of VH + CH1, or "Fd") and a light chain-derived Fab fragment (e.g., comprising, consisting of, or consisting essentially of VL + CL) may be linked in any arrangement to form a scFab. For example, a scFab may be arranged, in N-terminal to C-terminal direction, according to (heavy chain Fab fragment – linker – light chain Fab fragment) or (light chain Fab fragment – linker – heavy chain Fab fragment). Peptide linkers and exemplary linker sequences for use in scFabs are discussed in further detail herein. "Fv" is a small antibody fragment that contains a complete antigen-recognition and antigen-binding site. This fragment generally consists of a dimer of one heavy- and one light-chain variable region domain in tight, non-covalent association. However, even a single variable domain (or half of an Fv comprising only three CDRs specific for an antigen) has the ability to recognize and bind antigen, although typically at a lower affinity than the entire binding site. "Single-chain Fv" also abbreviated as "sFv" or "scFv", are antibody fragments that comprise the VH and VL antibody domains connected into a single polypeptide chain. In some embodiments, the scFv polypeptide comprises a polypeptide linker disposed between and linking the VH and VL domains that enables the scFv to retain or form the desired structure for antigen binding. Such a peptide linker can be incorporated into a fusion polypeptide using standard techniques well known in the art. For a review of scFv, see Pluckthun in The Pharmacology of Monoclonal Antibodies, vol.113, Rosenburg and Moore eds., Springer-Verlag, New York, pp.269-315 (1994); Borrebaeck 1995, infra. In certain embodiments, the antibody or antigen-binding fragment comprises a scFv comprising a VH domain, a VL domain, and a peptide linker linking the VH domain to the VL domain. In particular embodiments, a scFv comprises a VH domain linked to a VL domain by a peptide linker, which can be in a VH-linker- VL orientation or in a VL-linker-VH orientation. Any scFv of the present disclosure may be engineered so that the C-terminal end of the VL domain is linked by a short peptide sequence to the N-terminal end of the VH domain, or vice versa (i.e., (N)VL(C)-linker-(N)VH(C) or (N)VH(C)-linker-(N)VL(C). Alternatively, in some embodiments, a linker may be linked to an N-terminal portion or end of the VH domain, the VL domain, or both. Peptide linker sequences may be chosen, for example, based on: (1) their ability to adopt a flexible extended conformation; (2) their inability or lack of ability to adopt a secondary structure that could interact with functional epitopes on the first and second polypeptides and/or on a target molecule; and/or (3) the lack or relative lack of hydrophobic or charged residues that might react with the polypeptides and/or target molecule. Other considerations regarding linker design (e.g., length) can include the conformation or range of conformations in which the VH and VL can form a functional antigen-binding site. In certain embodiments, peptide linker sequences contain, for example, Gly, Asn and Ser residues. Other near neutral amino acids, such as Thr and Ala, may also be included in a linker sequence. Other amino acid sequences which may be usefully employed as linker include those disclosed in Maratea et al., Gene 40:3946 (1985); Murphy et al., Proc. Natl. Acad. Sci. USA 83:82588262 (1986); U.S. Pat. No. 4,935,233, and U.S. Pat. No.4,751,180. Other illustrative and non-limiting examples of linkers may include, for example, Glu-Gly-Lys-Ser-Ser-Gly-Ser-Gly-Ser-Glu-Ser-Lys- Val-Asp (SEQ ID NO: 19) (Chaudhary et al., Proc. Natl. Acad. Sci. USA 87:1066- 1070 (1990)) and Lys-Glu-Ser-Gly-Ser-Val-Ser-Ser-Glu-Gln-Leu-Ala-Gln-Phe-Arg- Ser-Leu-Asp (SEQ ID NO: 20) (Bird et al., Science 242:423-426 (1988)) and the pentamer Gly-Gly-Gly-Gly-Ser (SEQ ID NO: 21) when present in a single iteration or repeated 1 to 5 or more times, or more; see, e.g., SEQ ID NO: 17. Any suitable linker may be used, and in general can be about 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 1523, 24, 25, 26, 27, 28, 29, 30, 40, 50, 60, 70, 80, 90, 100 amino acids in length, or less than about 200 amino acids in length, and will preferably comprise a flexible structure (can provide flexibility and room for conformational movement between two regions, domains, motifs, fragments, or modules connected by the linker), and will preferably be biologically inert and/or have a low risk of immunogenicity in a human. Exemplary linkers include those comprising or consisting of the amino acid sequence set forth in any one or more of SEQ ID NOs: 10-21. In certain embodiments, the linker comprises or consists of an amino acid sequence having at least 75% (i.e., at least about 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or more) identity to the amino acid sequence set forth in any one of SEQ ID NOs: 10-21. scFv can be constructed using any combination of the VH and VL sequences or any combination of the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 sequences disclosed herein. In some embodiments, linker sequences are not required; for example, when the first and second polypeptides have non-essential N-terminal amino acid regions that can be used to separate the functional domains and prevent steric interference. During antibody development, DNA in the germline variable (V), joining (J), and diversity (D) gene loci may be rearranged and insertions and/or deletions of nucleotides in the coding sequence may occur. Somatic mutations may be encoded by the resultant sequence, and can be identified by reference to a corresponding known germline sequence. In some contexts, somatic mutations that are not critical to a desired property of the antibody (e.g., binding to a SARS-CoV-2 antigen), or that confer an undesirable property upon the antibody (e.g., an increased risk of immunogenicity in a subject administered the antibody), or both, may be replaced by the corresponding germline-encoded amino acid, or by a different amino acid, so that a desirable property of the antibody is improved or maintained and the undesirable property of the antibody is reduced or abrogated. Thus, in some embodiments, the antibody or antigen-binding fragment of the present disclosure comprises at least one more germline-encoded amino acid in a variable region as compared to a parent antibody or antigen-binding fragment, provided that the parent antibody or antigen binding fragment comprises one or more somatic mutations. Variable region and CDR amino acid sequences of exemplary anti-SARS-CoV-2 antibodies of the present disclosure are provided in Tables 1 and 2 herein. In certain embodiments, an antibody or antigen-binding fragment comprises an amino acid modification (e.g., a substitution mutation) to remove an undesired risk of oxidation, deamidation, and/or isomerization. Also provided herein are variant antibodies that comprise one or more amino acid alterations in a variable region (e.g., VH, VL, framework or CDR) as compared to a presently disclosed antibody, wherein the variant antibody is capable of binding to a SARS-CoV-2 antigen. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure is monospecific (e.g., binds to a single epitope) or is multispecific (e.g., binds to multiple epitopes and/or target molecules). Antibodies and antigen binding fragments may be constructed in various formats. Exemplary antibody formats disclosed in Spiess et al., Mol. Immunol.67(2):95 (2015), and in Brinkmann and Kontermann, mAbs 9(2):182-212 (2017), which formats and methods of making the same are incorporated herein by reference and include, for example, Bispecific T cell Engagers (BiTEs), DARTs, Knobs-Into-Holes (KIH) assemblies, scFv-CH3-KIH assemblies, KIH Common Light-Chain antibodies, TandAbs, Triple Bodies, TriBi Minibodies, Fab-scFv, scFv-CH-CL-scFv, F(abʹ)2-scFv2, tetravalent HCabs, Intrabodies, CrossMabs, Dual Action Fabs (DAFs) (two-in-one or four-in-one), DutaMabs, DT-IgG, Charge Pairs, Fab-arm Exchange, SEEDbodies, Triomabs, LUZ-Y assemblies, Fcabs, κλ-bodies, orthogonal Fabs, DVD-Igs (e.g., US Patent No. 8,258,268, which formats are incorporated herein by reference in their entirety), IgG(H)-scFv, scFv-(H)IgG, IgG(L)-scFv, scFv-(L)IgG, IgG(L,H)-Fv, IgG(H)-V, V(H)- IgG, IgG(L)-V, V(L)-IgG, KIH IgG-scFab, 2scFv-IgG, IgG-2scFv, scFv4-Ig, Zybody, and DVI-IgG (four-in-one), as well as so-called FIT-Ig (e.g., PCT Publication No. WO 2015/103072, which formats are incorporated herein by reference in their entirety), so- called WuxiBody formats (e.g., PCT Publication No. WO 2019/057122, which formats are incorporated herein by reference in their entirety), and so-called In-Elbow-Insert Ig formats (IEI-Ig; e.g., PCT Publication Nos. WO 2019/024979 and WO 2019/025391, which formats are incorporated herein by reference in their entirety). In certain embodiments, the antibody or antigen-binding fragment comprises two or more of VH domains, two or more VL domains, or both (i.e., two or more VH domains and two or more VL domains). In particular embodiments, an antigen-binding fragment comprises the format (N-terminal to C-terminal direction) VH-linker-VL- linker-VH-linker-VL, wherein the two VH sequences can be the same or different and the two VL sequences can be the same or different. Such linked scFvs can include any combination of VH and VL domains arranged to bind to a given target, and in formats comprising two or more VH and/or two or more VL, one, two, or more different eptiopes or antigens may be bound. It will be appreciated that formats incorporating multiple antigen-binding domains may include VH and/or VL sequences in any combination or orientation. For example, the antigen-binding fragment can comprise the format VL-linker-VH-linker-VL-linker-VH, VH-linker-VL-linker-VL-linker-VH, or VL-linker-VH-linker-VH-linker-VL. Monospecific or multispecific antibodies or antigen-binding fragments of the present disclosure constructed comprise any combination of the VH and VL sequences and/or any combination of the CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 sequences disclosed herein. A bispecific or multispecific antibody or antigen- binding fragment may, in some embodiments, comprise one, two, or more antigen- binding domains (e.g., a VH and a VL) of the instant disclosure. Two or more binding domains may be present that bind to the same or a different SARS-CoV-2 epitope, and a bispecific or multispecific antibody or antigen-binding fragment as provided herein can, in some embodiments, comprise a further SARS-CoV-2 binding domain, and/or can comprise a binding domain that binds to a different antigen or pathogen altogether. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment can be multispecific; e.g., bispecific, trispecific, or the like. In certain embodiments, the antibody or antigen-binding fragment comprises a Fc polypeptide, or a fragment thereof. The "Fc" fragment or Fc polypeptide comprises the carboxy-terminal portions (i.e., the CH2 and CH3 domains of IgG) of both antibody H chains held together by disulfides. Antibody "effector functions" refer to those biological activities attributable to the Fc region (a native sequence Fc region or amino acid sequence variant Fc region) of an antibody, and vary with the antibody isotype. Examples of antibody effector functions include: C1q binding and complement dependent cytotoxicity; Fc receptor binding; antibody-dependent cell-mediated cytotoxicity (ADCC); phagocytosis; down regulation of cell surface receptors (e.g., B cell receptor); and B cell activation. As discussed herein, modifications (e.g., amino acid substitutions) may be made to an Fc domain in order to modify (e.g., improve, reduce, or ablate) one or more functionality of an Fc-containing polypeptide (e.g., an antibody of the present disclosure). Such functions include, for example, Fc receptor (FcR) binding, antibody half-life modulation (e.g., by binding to FcRn), ADCC function, protein A binding, protein G binding, and complement binding. Amino acid modifications that modify (e.g., improve, reduce, or ablate) Fc functionalities include, for example, the T250Q/M428L, M252Y/S254T/T256E, H433K/N434F, M428L/N434S, E233P/L234V/L235A/G236 + A327G/A330S/P331S, E333A, S239D/A330L/I332E, P257I/Q311, K326W/E333S, S239D/I332E/G236A, N297Q, K322A, S228P, L235E + E318A/K320A/K322A, L234A/L235A (also referred to herein as “LALA”), and L234A/L235A/P329G mutations, which mutations are summarized and annotated in "Engineered Fc Regions", published by InvivoGen (2011) and available online at invivogen.com/PDF/review/review-Engineered-Fc-Regions- invivogen.pdf?utm_source=review&utm_medium=pdf&utm_ campaign=review&utm_content=Engineered-Fc-Regions, and are incorporated herein by reference. For example, to activate the complement cascade, the C1q protein complex can bind to at least two molecules of IgG1 or one molecule of IgM when the immunoglobulin molecule(s) is attached to the antigenic target (Ward, E. S., and Ghetie, V., Ther. Immunol.2 (1995) 77-94). Burton, D. R., described (Mol. Immunol. 22 (1985) 161-206) that the heavy chain region comprising amino acid residues 318 to 337 is involved in complement fixation. Duncan, A. R., and Winter, G. (Nature 332 (1988) 738-740), using site directed mutagenesis, reported that Glu318, Lys320 and Lys322 form the binding site to C1q. The role of Glu318, Lys320 and Lys 322 residues in the binding of C1q was confirmed by the ability of a short synthetic peptide containing these residues to inhibit complement mediated lysis. For example, FcR binding can be mediated by the interaction of the Fc moiety (of an antibody) with Fc receptors (FcRs), which are specialized cell surface receptors on cells including hematopoietic cells. Fc receptors belong to the immunoglobulin superfamily, and shown to mediate both the removal of antibody-coated pathogens by phagocytosis of immune complexes, and the lysis of erythrocytes and various other cellular targets (e.g., tumor cells) coated with the corresponding antibody, via antibody dependent cell mediated cytotoxicity (ADCC; Van de Winkel, J. G., and Anderson, C. L., J. Leukoc. Biol.49 (1991) 511-524). FcRs are defined by their specificity for immunoglobulin classes; Fc receptors for IgG antibodies are referred to as FcγR, for IgE as FcεR, for IgA as FcαR and so on and neonatal Fc receptors are referred to as FcRn. Fc receptor binding is described for example in Ravetch, J. V., and Kinet, J. P., Annu. Rev. Immunol.9 (1991) 457-492; Capel, P. J., et al., Immunomethods 4 (1994) 25-34; de Haas, M., et al., J Lab. Clin. Med.126 (1995) 330-341; and Gessner, J. E., et al., Ann. Hematol.76 (1998) 231-248. Cross-linking of receptors by the Fc domain of native IgG antibodies (FcγR) triggers a wide variety of effector functions including phagocytosis, antibody-dependent cellular cytotoxicity, and release of inflammatory mediators, as well as immune complex clearance and regulation of antibody production. Fc moieties providing cross- linking of receptors (e.g., FcγR) are contemplated herein. In humans, three classes of FcγR have been characterized to-date, which are: (i) FcγRI (CD64), which binds monomeric IgG with high affinity and is expressed on macrophages, monocytes, neutrophils and eosinophils; (ii) FcγRII (CD32), which binds complexed IgG with medium to low affinity, is widely expressed, in particular on leukocytes, is believed to be a central player in antibody-mediated immunity, and which can be divided into FcγRIIA, FcγRIIB and FcγRIIC, which perform different functions in the immune system, but bind with similar low affinity to the IgG-Fc, and the ectodomains of these receptors are highly homologuous; and (iii) FcγRIII (CD16), which binds IgG with medium to low affinity and has been found in two forms: FcγRIIIA, which has been found on NK cells, macrophages, eosinophils, and some monocytes and T cells, and is believed to mediate ADCC; and FcγRIIIB, which is highly expressed on neutrophils. FcγRIIA is found on many cells involved in killing (e.g., macrophages, monocytes, neutrophils) and seems able to activate the killing process. FcγRIIB seems to play a role in inhibitory processes and is found on B-cells, macrophages and on mast cells and eosinophils. Importantly, it has been shown that 75% of all FcγRIIB is found in the liver (Ganesan, L. P. et al., 2012: “FcγRIIb on liver sinusoidal endothelium clears small immune complexes,” Journal of Immunology 189: 4981–4988). FcγRIIB is abundantly expressed on Liver Sinusoidal Endothelium, called LSEC, and in Kupffer cells in the liver and LSEC are the major site of small immune complexes clearance (Ganesan, L. P. et al., 2012: FcγRIIb on liver sinusoidal endothelium clears small immune complexes. Journal of Immunology 189: 4981–4988). In some embodiments, the antibodies disclosed herein and the antigen-binding fragments thereof comprise an Fc polypeptide or fragment thereof for binding to FcγRIIb, in particular an Fc region, such as, for example IgG-type antibodies. Moreover, it is possible to engineer the Fc moiety to enhance FcγRIIB binding by introducing the mutations S267E and L328F as described by Chu, S. Y. et al., 2008: Inhibition of B cell receptor-mediated activation of primary human B cells by coengagement of CD19 and FcgammaRIIb with Fc-engineered antibodies. Molecular Immunology 45, 3926–3933. Thereby, the clearance of immune complexes can be enhanced (Chu, S., et al., 2014: Accelerated Clearance of IgE In Chimpanzees Is Mediated By Xmab7195, An Fc-Engineered Antibody With Enhanced Affinity For Inhibitory Receptor FcγRIIb. Am J Respir Crit, American Thoracic Society International Conference Abstracts). In some embodiments, the antibodies of the present disclosure, or the antigen binding fragments thereof, comprise an engineered Fc moiety with the mutations S267E and L328F, in particular as described by Chu, S. Y. et al., 2008: Inhibition of B cell receptor-mediated activation of primary human B cells by coengagement of CD19 and FcgammaRIIb with Fc-engineered antibodies. Molecular Immunology 45, 3926–3933. On B cells, FcγRIIB may function to suppress further immunoglobulin production and isotype switching to, for example, the IgE class. On macrophages, FcγRIIB is thought to inhibit phagocytosis as mediated through FcγRIIA. On eosinophils and mast cells, the B form may help to suppress activation of these cells through IgE binding to its separate receptor. Regarding FcγRI binding, modification in native IgG of at least one of E233- G236, P238, D265, N297, A327 and P329 reduces binding to FcγRI. IgG2 residues at positions 233-236, substituted into corresponding positions IgG1 and IgG4, reduces binding of IgG1 and IgG4 to FcγRI by 10 ³ -fold and eliminated the human monocyte response to antibody-sensitized red blood cells (Armour, K. L., et al. Eur. J. Immunol. 29 (1999) 2613-2624). Regarding FcγRII binding, reduced binding for FcγRIIA is found, e.g., for IgG mutation of at least one of E233-G236, P238, D265, N297, A327, P329, D270, Q295, A327, R292 and K414. Two allelic forms of human FcγRIIA are the "H131" variant, which binds to IgG1 Fc with high affinity, and the "R131" variant, which binds to IgG1 Fc with low affinity. See, e.g., Bruhns et al., Blood 113:3716-3725 (2009). Regarding FcγRIII binding, reduced binding to FcγRIIIA is found, e.g., for mutation of at least one of E233-G236, P238, D265, N297, A327, P329, D270, Q295, A327, S239, E269, E293, Y296, V303, A327, K338 and D376. Mapping of the binding sites on human IgG1 for Fc receptors, the above-mentioned mutation sites, and methods for measuring binding to FcγRI and FcγRIIA, are described in Shields, R. L., et al., J. Biol. Chem.276 (2001) 6591-6604. Two allelic forms of human FcγRIIIA are the "F158" variant, which binds to IgG1 Fc with low affinity, and the “V158” variant, which binds to IgG1 Fc with high affinity. See, e.g., Bruhns et al., Blood 113:3716-3725 (2009). Regarding binding to FcγRII, two regions of native IgG Fc appear to be involved in interactions between FcγRIIs and IgGs, namely (i) the lower hinge site of IgG Fc, in particular amino acid residues L, L, G, G (234 – 237, EU numbering), and (ii) the adjacent region of the CH2 domain of IgG Fc, in particular a loop and strands in the upper CH2 domain adjacent to the lower hinge region, e.g., in a region of P331 (Wines, B.D., et al., J. Immunol.2000; 164: 5313 – 5318). Moreover, FcγRI appears to bind to the same site on IgG Fc, whereas FcRn and Protein A bind to a different site on IgG Fc, which appears to be at the CH2-CH3 interface (Wines, B.D., et al., J. Immunol. 2000; 164: 5313 – 5318). Also contemplated are mutations that increase binding affinity of an Fc polypeptide or fragment thereof of the present disclosure to a (i.e., one or more) Fcγ receptor (e.g., as compared to a reference Fc polypeptide or fragment thereof or containing the same that does not comprise the mutation(s)). See, e.g., Delillo and Ravetch, Cell 161(5):1035-1045 (2015) and Ahmed et al., J. Struc. Biol.194(1):78 (2016), the Fc mutations and techniques of which are incorporated herein by reference. In any of the herein disclosed embodiments, an antibody or antigen-binding fragment can comprise a Fc polypeptide or fragment thereof comprising a mutation selected from G236A; S239D; A330L; and I332E; or a combination comprising any two or more of the same; e.g., S239D/I332E; S239D/A330L/I332E; G236A/S239D/I332E; G236A/A330L/I332E (also referred to herein as "GAALIE"); or G236A/S239D/A330L/I332E. In some embodiments, the Fc polypeptide or fragment thereof does not comprise S239D. In some embodiments, the Fc polypeptide or fragment thereof comprises S at position 239. In certain embodiments, the Fc polypeptide or fragment thereof may comprise or consist of at least a portion of an Fc polypeptide or fragment thereof that is involved in binding to FcRn binding. In certain embodiments, the Fc polypeptide or fragment thereof comprises one or more amino acid modifications that improve binding affinity for (e.g., enhance binding to) FcRn (e.g., at a pH of about 6.0) and, in some embodiments, thereby extend in vivo half-life of a molecule comprising the Fc polypeptide or fragment thereof (e.g., as compared to a reference Fc polypeptide or fragment thereof or antibody that is otherwise the same but does not comprise the modification(s)). In certain embodiments, the Fc polypeptide or fragment thereof comprises or is derived from a IgG Fc and a half-life-extending mutation comprises any one or more of: M428L; N434S; N434H; N434A; N434S; M252Y; S254T; T256E; T250Q; P257I Q311I; D376V; T307A; E380A (EU numbering). In certain embodiments, a half-life-extending mutation comprises M428L/N434S (also referred to herein as "MLNS" and "LS"). In certain embodiments, a half-life-extending mutation comprises M252Y/S254T/T256E. In certain embodiments, a half-life-extending mutation comprises T250Q/M428L. In certain embodiments, a half-life-extending mutation comprises P257I/Q311I. In certain embodiments, a half-life-extending mutation comprises P257I/N434H. In certain embodiments, a half-life-extending mutation comprises D376V/N434H. In certain embodiments, a half-life-extending mutation comprises T307A/E380A/N434A. In some embodiments, an antibody or antigen-binding fragment includes a Fc moiety that comprises the substitution mutations M428L/N434S. In some embodiments, an antibody or antigen-binding fragment includes a Fc polypeptide or fragment thereof that comprises the substitution mutations G236A/A330L/I332E. In certain embodiments, an antibody or antigen-binding fragment includes a (e.g., IgG) Fc moiety that comprises a G236A mutation, an A330L mutation, and a I332E mutation (GAALIE), and does not comprise a S239D mutation (e.g., comprises a native S at position 239). In particular embodiments, an antibody or antigen-binding fragment includes an Fc polypeptide or fragment thereof that comprises the substitution mutations: M428L/N434S and G236A/A330L/I332E, and optionally does not comprise S239D. In certain embodiments, an antibody or antigen-binding fragment includes a Fc polypeptide or fragment thereof that comprises the substitution mutations: M428L/N434S and G236A/S239D/A330L/I332E. An antibody or antigen-binding fragment of the present disclosure may be of any allotype or combination of allotypes. “Allotype” refers to the allelic variation found among the IgG subclasses. For example, an allotype may comprise G1m1 (or G1m(a)), G1m2 (or G1m(x)), G1m3 (or G1m(f)), G1m17 (or Gm(z))m, G1m27, and/or G1m28 (G1m27 and G1m28 have been described as “alloallotypes”). The G1m3 and G1m17 allotypes are located at the same position in the CH1 domain (position 214 according to EU numbering). G1m3 comprises R214 (EU), while G1m17 comprises K214 (EU). The G1m1 allotype is located in the CH3 domain (at positions 356 and 358 (EU)) and refers to the replacements E356D and M358L. The G1m2 allotype refers to a replacement of the alanine in position 431 (EU) by a glycine. G1m allotypes, alloallotypes, and features thereof are known in the art and described at, for example, www.imgt.org/IMGTrepertoire/Proteins/allotypes/human/IGH/IGH C/G1m_allotypes.ht ml and Lefranc, M.-P. and Lefranc, G. Human Gm, Km and Am allotypes and their molecular characterization: a remarkable demonstration of polymorphism In: B. Tait, F. Christiansen (Eds.), Immunogenetics, chap.34, Humana Press, Springer, New York, USA. Methods Mol. Biol.2012; 882, 635-680. PMID: 22665258, LIGM: 406, the contents and allotypes and allotype information of which are incorporated herein by reference. The G1m1 allotype may be combined, for example, with the G1m3, G1m17, G1m27, G1m2, and/or G1m28 allotype. In some embodiments, an allotype is G1m3 with no G1m1 (G1m3,-1). In some embodiments, an allotype is G1m17,1 allotype. In some embodiments, an allotype is G1m3,1. In some embodiments, an allotype is G1m17 with no G1m1 (G1m17,-1). Optionally, these allotypes may be combined (or not combined) with the G1m2, G1m27 or G1m28 allotype. For example, an allotype may be G1m17,1,2. In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a G1m3 allotype. In some embodiments, an antibody or antigen- binding fragment of the present disclosure comprises a G1m3, allotype and comprises M428L and N434S mutations in CH3, as described further herein. In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a G1m17, 1 allotype. In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a G1m17, 1 allotype and comprises M428L and N434S mutations in CH3, as described further herein. In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a CH1-CH3 amino acid sequence as set forth in any one of SEQ ID Nos.:6, 7, 127, 128, and 19. In certain embodiments, the antibody or antigen-binding fragment comprises a mutation that alters glycosylation, wherein the mutation that alters glycosylation comprises N297A, N297Q, or N297G, and/or the antibody or antigen-binding fragment is partially or fully aglycosylated and/or is partially or fully afucosylated. Host cell lines and methods of making partially or fully aglycosylated or partially or fully afucosylated antibodies and antigen-binding fragments are known (see, e.g., PCT Publication No. WO 2016/181357; Suzuki et al. Clin. Cancer Res.13(6):1875-82 (2007); Huang et al. MAbs 6:1-12 (2018)). Fucosylation of an Fc polypeptide or fragment thereof, or of an antibody, can be effected by introducing amino acid mutations to introduce or disrupt a fucosylation site; by expressing the antibody or antigen-binding fragment thereof in a host cell which has been genetically engineered to lack the ability (or have an inhibited or compromised ability) to fucosylate the antibody or antigen-binding fragment thereof; by expressing the antibody or antigen-binding fragment thereof under conditions in which a host cell is impaired in its ability to fucosylate the antibody or antigen-binding fragment thereof (e.g., in the presence of 2- fluoro-L-fucose (2FF)), or the like. In certain embodiments, an antibody or antigen-binding fragment: is afucosylated; has been produced in a host cell that is incapable of fucosylation or that is inhibited in its ability to fucosylate the antibody or antigen-binding fragment thereof; has been produced under conditions that inhibit fucosylation thereof by a host cell; or any combination thereof. In certain embodiments, an antibody or antigen-binding fragment comprises an amino acid mutation that (1) inhibits fucosylation as compared to a reference antibody or antigen-binding fragment (i.e. that is otherwise the same as the antibody or antigen- binding fragment), respectively, and/or (2) that abrogates a fucosylation site that is present in the reference antibody or antigen-binding fragment, respectively.In certain embodiments, the antibody or antigen-binding fragment is capable of eliciting continued protection in vivo in a subject even once no detectable levels of the antibody or antigen-binding fragment can be found in the subject (i.e., when the antibody or antigen-binding fragment has been cleared from the subject following administration). Such protection is referred to herein as a vaccinal effect. Without wishing to be bound by theory, it is believed that dendritic cells can internalize complexes of antibody and antigen and thereafter induce or contribute to an endogenous immune response against antigen. In certain embodiments, an antibody or antigen-binding fragment comprises one or more modifications, such as, for example, mutations in the Fc comprising G236A, A330L, and I332E, that are capable of activating dendritic cells that may induce, e.g., T cell immunity to the antigen. In certain embodiments, an antibody or antigen-binding fragment comprises a Fc variant (shown in the below table as fucosylated, unless otherwise indicated) as shown in the following table; see also International Application PCT/US2022/030556. In certain embodiments, an antibody or antigen-bindign fragment of the present disclosure comprises a Fc polypeptide comprising a mutation or combination of mutations disclosed in International Application PCT/US2022/030556, which mutations and combinations of mutations (and fucosylated and afucosylated antibodies and antigen-binding fragments comprising the same) are incorporated herein by reference. Table of Certain Fc Variants and Properties Thereof Additional features of disclosed Fc variant-containing antibodies and antigen- binding fragments are described herein. In some embodiments, an antibody or antigen-binding fragment comprises, in an (e.g., human) IgG1 heavy chain, the amino acid mutation(s) set forth in any one of (i)- (xviii): (i) G236A, L328V, and Q295E; (ii) G236A, P230A, and Q295E; (iii) G236A, R292P, and I377N; (iv) G236A, K334A, and Q295E; (v) G236S, R292P, and Y300L; (vi) G236A and Y300L; (vii) G236A, R292P, and Y300L; (viii) G236S, G420V, G446E, and L309T; (ix) G236A and R292P; (x) R292P and Y300L; (xi) G236A and R292P; (xii) Y300L; (xiii) E345K, G236S, L235Y, and S267E; (xiv) E272R, L309T, S219Y, and S267E; (xv) G236Y; (xvi) G236W; (xvii) F243L, G446E, P396L, and S267E; (xviii) G236A, S239D, and H268E, wherein the numbering of amino acid residues is according to the EU index as set forth in Kabat. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In some embodiments, the antibody or antigen-binding fragment further comprises one or more mutation that enhances binding to a human FcRn, such as M428L and N434S mutations or M428L and N434A mutations (EU numbering) or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In some embodiments, the IgG1 heavy chain comprises a CH1-CH3 or a CH2-CH3 or a hinge-CH2-CH3, wherein the CH1-CH3 or CH2-CH3 or hinge-CH2-CH3 has at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity (or similarity) to a wild-type human IgG1 CH1-CH3 or CH2-CH3 or hinge-CH2-CH3, respectively. It will be understood that two or more amino acid substitutions present in a variant can be expressed in a variety of ways, for example, as G236A_Y300L, or as G236A/Y300L. Moreover, a mutation or combination mutation may be referenced using a short form including the original amino acid(s) and the amino acid(s) resulting from the substitution(s). For example, G236A may be described as “GA” or “236A”; G236A_Y300L may be described as “GAYL”; G236A_L328V_Q295E may be described as “GALVQE”; G236A_R292P_Y300L may be described as “GARPYL”, G236A_R292P_I377N may be described as “GARPIN”, or the like. In certain embodiments, a variant of an Fc polypeptide comprises only the specified or recited amino acid mutations (e.g., substitutions), and does not comprise any further amino acid substitutions or mutations; e.g., relative to the reference polypeptide (e.g., a wild-type Fc polypeptide or fragment thereof). For example, in some embodiments, a variant Fc polypeptide comprising the amino acid substitutions G236A_Y300L does not comprise any other amino acid substitutions; i.e., comprises an amino acid sequence that is wild-type except for G236A and Y300L. In some embodiments, a variant of an Fc polypeptide does not comprise R292P, does not comprise Y300L, or both. In any of the presently disclosed embodiments, a variant of an Fc polypeptide or fragment thereof can be derived from or comprise a human Fc polypeptide or fragment thereof, and/or can be derived from or comprise a human IgG1, a human IgG2, a human IgG3, or a human IgG4 isotype. In this context, the expression “derived from” means that the variant is the same as the referenced polypeptide or isotype, except for the specified modification(s) (e.g., amino acid substitution(s)). By way of example, a variant Fc polypeptide which comprises a wild-type human IgG1 Fc amino acid sequence except for the amino acid substitution mutations G236A_L328V_Q295E (and, optionally, other amino acid substitutions) can be said to be “derived from” wild-type human IgG1 Fc. In any of the presently disclosed embodiments, a polypeptide, CH2, Fc, Fc fragment, antibody, or antigen-binding fragment may comprise human Ig sequence, such as human IgG1 sequence. In some embodiments, the polypeptide, CH2, Fc, Fc fragment, antibody, or antigen-binding fragment can comprise a native or wild- type human Ig sequence with the exception of the described mutation(s), or can comprise a human Ig (e.g. IgG) sequence that contains one or more additional mutations. In certain embodiments, an antibody of the present disclosure comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, a valine (V) at EU position 328, and a glutamic acid (E) at EU position 295. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GALVQE”). In some embodiments, the antibody further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: (i) an IgG hinge-CH2 polypeptide; or (ii) an IgG hinge-Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, an alanine (A) at EU position 230, and a glutamic acid (E) at EU position 295. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GAPAQE”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, a proline (P) at EU position 292, and an asparagine (N) at EU position 377. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GARPIN”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, an alanine (A) at EU position 334, and a glutamic acid (E) at EU position 295. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GAKAQE”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a serine (S) at EU position 236, a proline (P) at EU position 292, and a leucine (L) at EU position 300. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GSRPYL”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, a proline (P) at EU position 292, and a leucine (L) at EU position 300. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GARPYL”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236 and a leucine (L) at EU position 300. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GAYL”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. In certain other embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of: (i) an IgG CH2 polypeptide; or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, an aspartic acid (D) at EU position 239, and a glutamic acid (E) at EU position 268. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GASDHE”). In some embodiments, the antibody or antigen-binding fragment further comprises the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein. In certain embodiments, the antibody or antigen-binding fragment is afucosylated. Also provided is an antibody or antigen-binding fragment of the present disclosure comprising a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236 and a leucine (L) at EU position 300. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GAYL”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, a proline (P) at EU position 292, and a leucine (L) at EU position 300. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GARPYL”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of an IgG Fc polypeptide, wherein the variant comprises a serine (S) at EU position 236, a valine (V) at EU position 420, a glutamic acid (E) at EU position 446, and a threonine (T) at EU position 309. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GSGVGELT”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide, wherein the variant comprises an alanine (A) at EU position 236 and a proline (P) at EU position 292. In some embodiments, the antibody or antigen-binding fragment comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GARP”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide, wherein the variant comprises a proline (P) at EU position 292 and a leucine (L) at EU position 300, and wherein, optionally, variant and, further optionally, the antibody has increased binding to a human FcγRIIIa with as compared to the binding of a reference antibody to the human FcγRIIIa, wherein, optionally, the binding is as determined using an electrochemiluminescence assay, further optionally Meso Scale Discovery. In some embodiments, the antibody or antigen-binding fragment comprises an (e.g., otherwise wild-type) IgG1 CH2 polypeptide or IgG Fc polypeptide (“RPYL”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a leucine (L) at EU position 300. In some embodiments, the IgG CH2 polypeptide or IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“YL”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a lysine (K) at EU position 345, a serine (S) at EU position 236, tyrosine (Y) at EU position 235, and a glutamic acid (E) at EU position 267. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GSEKLYSE”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG hinge-CH2 polypeptide or (ii) an IgG hinge-Fc polypeptide or a fragment thereof, wherein the variant comprises an arginine (R) at EU position 272, a threonine (T) at EU position 309, a tyrosine (Y) at EU position 219, and a glutamic acid (E) at EU position 267. In some embodiments, the IgG hinge-CH2 polypeptide or an IgG hinge-Fc polypeptide or a fragment thereof comprises an (e.g. otherwise wild-type) IgG1 hinge-CH2 polypeptide or IgG hinge-Fc polypeptide or a fragment thereof (“SYSEERLT”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a tyrosine (Y) at EU position 236. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GY”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a tryptophan (W) at EU position 236. In some embodiments, the IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof comprises an (e.g., otherwise wild-type) IgG1 CH2 polypeptide or Fc polypeptide or fragment thereof (“GW”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, wherein the IgG Fc polypeptide or fragment thereof, and optionally the polypeptide, is afucosylated, and wherein, further optionally, the variant comprises a leucine (L) at EU position 330 and a glutamic acid (E) at EU postion 332, wherein, still further optionally, the variant does not comprise an aspartic acid (D) at EU position 239, and, even further optionally, comprises a serine (S) at EU position 239. In some embodiments, the IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof comprises an (e.g., otherwise wild-type) IgG1 CH2 polypeptide or Fc polypeptide or fragment thereof (“GA-afuc” or “GAALIE-afuc”, respectively). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. Also provided is an antibody or antigen-binding fragment of the present disclosure that comprises a variant of an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises a leucine (L) at EU position 243, a glutamic acid (E) at EU position 446, a leucine (L) at EU position 396, and a glutamic acid (E) at EU position 267. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“FLSEPLGE”). In certain further embodiments, the mutations M428L and N434S, or the mutations M428L and N434A, or any other mutation(s) that enhance binding to a human FcRn, such as those described herein, are present. In certain embodiments, the antibody or antigen-binding fragment is afucoyslated. Also provided is an antibody or antigen-binding fragment that comprises a variant of: (i) an IgG CH2 polypeptide or (ii) an IgG Fc polypeptide or a fragment thereof, wherein the variant comprises an alanine (A) at EU position 236, an aspartic acid (D) at EU position 239, a glutamic acid (E) and EU position 332, a leucine (L) at EU position 428, and a serine (S) or an alanine (A) at EU position 434. In some embodiments, the IgG Fc polypeptide or fragment thereof comprises an (e.g., otherwise wild-type) IgG1 Fc polypeptide or fragment thereof (“GASDIEMLNS” or “GASDIEMLNA”). In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of an (e.g. IgG1) IgG Fc polypeptide, wherein the variant comprises the following mutations, according to EU numbering: (i) M428L, N434S, G236A, L328V, and Q295E; (ii) M428L, N434S, G236A, R292P, and I377N; (iii) M428L, N434S, G236A, and Y300L; (iv) M428L, N434S, G236A, R292P, and Y300L; (v) M428L, N434S, G236A, L328V, and Q295E, wherein the antibody or antigen- binding fragment or antigen-binding fragment is afucosylated; (vi) M428L, N434S, G236A, R292P, and I377N, wherein the antibody or antigen-binding fragment is afucosylated; (vii) M428L, N434S, G236A, and Y300L, wherein the antibody or antigen-binding fragment is afucosylated; or (viii) M428L, N434S, G236A, R292P, and Y300L, wherein the antibody or antigen-binding fragment is afucosylated. In some embodiments, the variant of an (e.g., IgG1) IgG Fc polypeptide comprises amino acid substitutions that consist essentially of the substitution mutations in (i), (ii), (iii), (iv), (v), (vi), (vii), or (viii) above. In some embodiments, the antibody or antigen-binding fragment comprises a kappa light chain. In some embodiments, an antibody or antigen-binding fragment of the present disclosure comprises a variant of an (e.g. IgG1) IgG Fc polypeptide, wherein the variant comprises the following mutations, according to EU numbering: (i) M428L, N434A, G236A, L328V, and Q295E; (ii) M428L, N434A, G236A, R292P, and I377N; (iii) M428L, N434A, G236A, and Y300L; (iv) M428L, N434A, G236A, R292P, and Y300L; (v) M428L, N434A, G236A, L328V, and Q295E, wherein the antibody or antigen-binding fragment is afucosylated; (vi) M428L, N434A, G236A, R292P, and I377N, wherein the antibody or antigen-binding fragment is afucosylated; (vii) M428L, N434A, G236A, and Y300L, wherein the antibody or antigen-binding fragment is afucosylated; or (viii) M428L, N434A, G236A, R292P, and Y300L, wherein the antibody or antigen-binding fragment is afucosylated. In some embodiments, the variant of an IgG Fc polypeptide comprises amino acid substitutions that consist essentially of the substitution mutations in (i), (ii), (iii), (iv), (v), (vi), (vii), or (viii) above. In some embodiments, the antibody or antigen-binding fragment comprises a kappa light chain. In certain embodiments, the antibody or antigen-binding fragment is capable of eliciting continued protection in vivo in a subject even once no detectable levels of the antibody or antigen-binding fragment can be found in the subject (i.e., when the antibody has been cleared from the subject following administration). Such protection is referred to herein as a vaccinal effect. Without wishing to be bound by theory, it is believed that dendritic cells can internalize complexes of antibody (or antigen-binding fragment) and antigen and thereafter induce or contribute to an endogenous immune response against antigen. In certain embodiments, an antibody or antigen-binding fragment comprises one or more modifications, such as, for example, mutations in the Fc comprising G236A, A330L, and I332E, that can activate dendritic cells that may induce, e.g., T cell immunity to the antigen. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment comprises a Fc polypeptide or a fragment thereof, including a CH2 (or a fragment thereof, a CH3 (or a fragment thereof), or a CH2 and a CH3, wherein the CH2, the CH3, or both can be of any isotype and may contain amino acid substitutions or other modifications as compared to a corresponding wild-type CH2 or CH3, respectively. In certain embodiments, a Fc of the present disclosure comprises two CH2-CH3 polypeptides that associate to form a dimer. In some embodiments, any of the presently disclosed antibodies or antigen- binding fragments can comprise an IgG1 isotype (optionally comprising an IgG1m3 allotype, an IgG1m3,1 allotype, an IgG1m17 allotype, or an IgG1m17,1 allotype) comprising (according to EU numbering): (i) M428L and N434S mutations; (ii) G236A, L328V, and Q295E mutations; (iii) G236A, L328V, Q259E, M428L, and N434S mutations; (iv) G236A, L328V, Q295E, M428L, and N434S mutations, wherein the antibody or antigen-binding fragment is afucosylated; (v) G236A, R292P, and Y300L mutations; (vi) G236A, R292P, Y300L, M428L, and N434S mutations; (vii) G236A, A330L, I332E, M428L, and N434S mutations; (viii) a G236A mutation, optionally wherein the antibody or antigen-binding fragment is afucosylated; (ix) G236A, M428L, and N434S mutations, optionally wherein the antibody or antigen- binding fragment is afucosylated; (x) G236R and L328R mutations; or (xi) G236R, L328R, M428L, and N434S mutations. In certain further embodiments, the antibody or antigen-binding fragment does not comprise any other mutations in the Fc. In some embodiments, the antibody or antigen-binding fragment thereof comprises an IgG1m3 allotype. In some embodiments, the antibody or antigen-binding fragment thereof comprises an IgG1m17 allotype. In some embodiments, the antibody or antigen- binding fragment thereof comprises an IgG1m3,1 allotype. In some embodiments, the antibody or antigen-binding fragment thereof comprises an IgG1m17,1 allotype. In particular embodiments, the antibody or antigen-binding fragment thereof comprises the VH amino acid sequence of SEQ ID NO.:101 and the VL amino acid sequence of SEQ ID NO.:105. In other embodiments, the antibody or antigen-binding fragment thereof comprises the VH amino acid sequence of SEQ ID NO.:135 and the VL amino acid sequence of SEQ ID NO.:113. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment comprises a Fc polypeptide or a fragment thereof, including a CH2 (or a fragment thereof, a CH3 (or a fragment thereof), or a CH2 and a CH3, wherein the CH2, the CH3, or both can be of any isotype and may contain amino acid substitutions or other modifications as compared to a corresponding wild-type CH2 or CH3, respectively. In certain embodiments, a Fc polypeptide of the present disclosure comprises two CH2-CH3 polypeptides that associate to form a dimer. In any of the presently disclosed embodiments, the antibody or antigen-binding fragment can be monoclonal. The term “monoclonal antibody” (mAb) as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., individual antibodies comprising the population are identical except for possible naturally occurring mutations that may be present, in some cases in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. Furthermore, in contrast to polyclonal antibody preparations that include different antibodies directed against different epitopes, each monoclonal antibody is directed against a single epitope of the antigen. In addition to their specificity, the monoclonal antibodies are advantageous in that they may be synthesized uncontaminated by other antibodies. The term "monoclonal" is not to be construed as requiring production of the antibody by any particular method. For example, monoclonal antibodies useful in the present invention may be prepared by the hybridoma methodology first described by Kohler et al., Nature 256:495 (1975), or may be made using recombinant DNA methods in bacterial, eukaryotic animal, or plant cells (see, e.g., U.S. Pat. No.4,816,567). Monoclonal antibodies may also be isolated from phage antibody libraries using the techniques described in Clackson et al., Nature, 352:624-628 (1991) and Marks et al., J. Mol. Biol., 222:581-597 (1991), for example. Monoclonal antibodies may also be obtained using methods disclosed in PCT Publication No. WO 2004/076677A2. Antibodies and antigen-binding fragments of the present disclosure include "chimeric antibodies" in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity (see, U.S. Pat. Nos.4,816,567; 5,530,101 and 7,498,415; and Morrison et al., Proc. Natl. Acad. Sci. USA, 81:6851-6855 (1984)). For example, chimeric antibodies may comprise human and non-human residues. Furthermore, chimeric antibodies may comprise residues that are not found in the recipient antibody or in the donor antibody. These modifications are made to further refine antibody performance. For further details, see Jones et al., Nature 321:522-525 (1986); Riechmann et al., Nature 332:323- 329 (1988); and Presta, Curr. Op. Struct. Biol.2:593-596 (1992). Chimeric antibodies also include primatized and humanized antibodies. A "humanized antibody" is generally considered to be a human antibody that has one or more amino acid residues introduced into it from a source that is non-human. These non-human amino acid residues are typically taken from a variable domain. Humanization may be performed following the method of Winter and co-workers (Jones et al., Nature, 321:522-525 (1986); Reichmann et al., Nature, 332:323-327 (1988); Verhoeyen et al., Science, 239:1534-1536 (1988)), by substituting non-human variable sequences for the corresponding sequences of a human antibody. Accordingly, such “humanized” antibodies are chimeric antibodies (U.S. Pat. Nos.4,816,567; 5,530,101 and 7,498,415) wherein substantially less than an intact human variable domain has been substituted by the corresponding sequence from a non-human species. In some instances, a "humanized" antibody is one which is produced by a non-human cell or animal and comprises human sequences, e.g., HC domains. A "human antibody" is an antibody containing only sequences that are present in an antibody that is produced by a human. However, as used herein, human antibodies may comprise residues or modifications not found in a naturally occurring human antibody (e.g., an antibody that is isolated from a human), including those modifications and variant sequences described herein. These are typically made to further refine or enhance antibody performance. In some instances, human antibodies are produced by transgenic animals. For example, see U.S. Pat. Nos.5,770,429; 6,596,541 and 7,049,426. In certain embodiments, an antibody or antigen-binding fragment of the present disclosure is chimeric, humanized, or human. Polynucleotides, Vectors, and Host cells In another aspect, the present disclosure provides isolated polynucleotides that encode any of the presently disclosed antibodies or an antigen-binding fragment thereof, or a portion thereof (e.g., a CDR, a VH, a VL, a heavy chain, or a light chain). In certain embodiments, the polynucleotide is codon-optimized for expression in a host cell. Once a coding sequence is known or identified, codon optimization can be performed using known techniques and tools, e.g., using the GenScript® OptimiumGene ^TM tool; see also Scholten et al., Clin. Immunol.119:135, 2006). Codon-optimized sequences include sequences that are partially codon-optimized (i.e., one or more codon is optimized for expression in the host cell) and those that are fully codon-optimized. It will also be appreciated that polynucleotides encoding antibodies and antigen- binding fragments of the present disclosure may possess different nucleotide sequences while still encoding a same antibody or antigen-binding fragment due to, for example, the degeneracy of the genetic code, splicing, and the like. In certain embodiments, the polynucleotide comprises a polynucleotide having at least 50% (i.e., 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%) identity to the polynucleotide sequence according to any one or more of SEQ ID NOs.:69, 71, 73, 74, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, and 99. It will be appreciated that in certain embodiments, a polynucleotide encoding an antibody or antigen-binding fragment is comprised in a polynucleotide that includes other sequences and/or features for, e.g., expression of the antibody or antigen-binding fragment in a host cell. Exemplary features include a promoter sequence, a polyadenylation sequence, a sequence that encodes a signal peptide (e.g., located at the N-terminus of a expressed antibody heavy chain or light chain), or the like. In any of the presently disclosed embodiments, the polynucleotide can comprise deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). In some embodiments, the RNA comprises messenger RNA (mRNA). In some embodiments, the polynucleotide comprises a modified nucleoside, a cap-1 structure, a cap-2 structure, or any combination thereof. In certain embodiments, the polynucleotide comprises a pseudouridine, a N6-methyladenonsine, a 5- methylcytidine, a 2-thiouridine, or any combination thereof. In some embodiments, the pseudouridine comprises N1-methylpseudouridine. Vectors are also provided, wherein the vectors comprise or contain a polynucleotide as disclosed herein (e.g., a polynucleotide that encodes an antibody or antigen-binding fragment that binds to SARS-CoV-2). A vector can comprise any one or more of the vectors disclosed herein. In particular embodiments, a vector is provided that comprises a DNA plasmid construct encoding the antibody or antigen-binding fragment, or a portion thereof (e.g., so-called "DMAb"; see, e.g., Muthumani et al., J Infect Dis.214(3):369-378 (2016); Muthumani et al., Hum Vaccin Immunother 9:2253- 2262 (2013)); Flingai et al., Sci Rep.5:12616 (2015); and Elliott et al., NPJ Vaccines 18 (2017), which antibody-coding DNA constructs and related methods of use, including administration of the same, are incorporated herein by reference). In certain embodiments, a DNA plasmid construct comprises a single open reading frame encoding a heavy chain and a light chain (or a VH and a VL) of the antibody or antigen- binding fragment, wherein the sequence encoding the heavy chain and the sequence encoding the light chain are optionally separated by polynucleotide encoding a protease cleavage site and/or by a polynucleotide encoding a self-cleaving peptide. In some embodiments, the substituent components of the antibody or antigen-binding fragment are encoded by a polynucleotide comprised in a single plasmid. In other embodiments, the substituent components of the antibody or antigen-binding fragment are encoded by a polynucleotide comprised in two or more plasmids (e.g., a first plasmid comprises a polynucleotide encoding a heavy chain, VH, or VH+CH, and a second plasmid comprises a polynucleotide encoding the cognate light chain, VL, or VL+CL). In certain embodiments, a single plasmid comprises a polynucleotide encoding a heavy chain and/or a light chain from two or more antibodies or antigen-binding fragments of the present disclosure. An exemplary expression vector is pVax1, available from Invitrogen®. A DNA plasmid of the present disclosure can be delivered to a subject by, for example, electroporation (e.g., intramuscular electroporation), or with an appropriate formulation (e.g., hyaluronidase). In some embodiments, a vector of the present disclosure comprises a nucleotide sequence encoding a signal peptide. The signal peptide may or may not be present (e.g., can be enzymatically cleaved from) on the mature antibody or antigen-binding fragment. In some embodiments, a vector of the present disclosure comprises a polyadenylation signal sequence. In some embodiments, a vector of the present disclosure comprises a CMV promoter. In some embodiments, a method is provided that comprises administering to a subject a first polynucleotide (e.g., mRNA) encoding an antibody heavy chain, a VH, or a Fd (VH + CH1), and administering to the subject a second polynucleotide (e.g., mRNA) encoding the cognate antibody light chain, VL, or VL+CL. In some embodiments, a polynucleotide (e.g., mRNA) is provided that encodes a heavy chain and a light chain of an antibody or antigen binding fragment thereof. In some embodiments, a polynucleotide (e.g., mRNA) is provided that encodes two heavy chains and two light chains of an antibody or antigen binding fragment thereof. See, e.g. Li, JQ., Zhang, ZR., Zhang, HQ. et al. Intranasal delivery of replicating mRNA encoding neutralizing antibody against SARS-CoV-2 infection in mice. Sig Transduct Target Ther 6, 369 (2021). https://doi.org/10.1038/s41392-021-00783-1, the antibody- encoding mRNA constructs, vectors, and related techniques of which are incorporated herein by reference. In some embodiments, a polynucleotide is delivered to a subject via an alphavirus replicon particle (VRP) delivery system. In some embodiments, a replicon comprises a modified VEEV replicon comprising two subgenomic promoters. In some embodiments, a polynucleotide or replicon can translate simultaneously the heavy chain (or VH, or VH+1) and the light chain (or VL, or VL+CL) of an antibody or antigen binding fragment thereof. In some embodiments, a method is provided that comprises delivering to a subject such a polynucleotide or replicon. In a further aspect, the present disclosure also provides a host cell expressing an antibody or antigen-binding fragment according to the present disclosure; or comprising or containing a vector or polynucleotide according the present disclosure. Examples of such cells include but are not limited to, eukaryotic cells, e.g., yeast cells, animal cells, insect cells, plant cells; and prokaryotic cells, including E. coli. In some embodiments, the cells are mammalian cells. In certain such embodiments, the cells are a mammalian cell line such as CHO cells (e.g., DHFR- CHO cells (Urlaub et al., PNAS 77:4216 (1980)), human embryonic kidney cells (e.g., HEK293T cells), PER.C6 cells, Y0 cells, Sp2/0 cells. NS0 cells, human liver cells, e.g., Hepa RG cells, myeloma cells or hybridoma cells. Other examples of mammalian host cell lines include mouse sertoli cells (e.g., TM4 cells); monkey kidney CV1 line transformed by SV40 (COS-7); baby hamster kidney cells (BHK); African green monkey kidney cells (VERO-76); monkey kidney cells (CV1); human cervical carcinoma cells (HELA); human lung cells (W138); human liver cells (Hep G2); canine kidney cells (MDCK; buffalo rat liver cells (BRL 3A); mouse mammary tumor (MMT 060562); TRI cells; MRC 5 cells; and FS4 cells. Mammalian host cell lines suitable for antibody production also include those described in, for example, Yazaki and Wu, Methods in Molecular Biology, Vol.248 (B. K. C. Lo, ed., Humana Press, Totowa, N.J.), pp.255- 268 (2003). In certain embodiments, a host cell is a prokaryotic cell, such as an E. coli. The expression of peptides in prokaryotic cells such as E. coli is well established (see, e.g., Pluckthun, A. Bio/Technology 9:545-551 (1991). For example, antibodies may be produced in bacteria, in particular when glycosylation and Fc effector function are not needed. For expression of antibody fragments and polypeptides in bacteria, see, e.g., U.S. Pat. Nos.5,648,237; 5,789,199; and 5,840,523. In particular embodiments, the cell may be transfected with a vector according to the present description with an expression vector. The term “transfection” refers to the introduction of nucleic acid molecules, such as DNA or RNA (e.g., mRNA) molecules, into cells, such as into eukaryotic cells. In the context of the present description, the term “transfection” encompasses any method known to the skilled person for introducing nucleic acid molecules into cells, such as into eukaryotic cells, including into mammalian cells. Such methods encompass, for example, electroporation, lipofection, e.g., based on cationic lipids and/or liposomes, calcium phosphate precipitation, nanoparticle based transfection, virus based transfection, or transfection based on cationic polymers, such as DEAE-dextran or polyethylenimine, etc. In certain embodiments, the introduction is non-viral. Moreover, host cells of the present disclosure may be transfected stably or transiently with a vector according to the present disclosure, e.g., for expressing an antibody, or an antigen-binding fragment thereof, according to the present disclosure. In such embodiments, the cells may be stably transfected with the vector as described herein. Alternatively, cells may be transiently transfected with a vector according to the present disclosure encoding an antibody or antigen-binding fragment as disclosed herein. In any of the presently disclosed embodiments, a polynucleotide may be heterologous to the host cell. Accordingly, the present disclosure also provides recombinant host cells that heterologously express an antibody or antigen-binding fragment of the present disclosure. For example, the cell may be of a species that is different to the species from which the antibody was fully or partially obtained (e.g., CHO cells expressing a human antibody or an engineered human antibody). In some embodiments, the cell type of the host cell does not express the antibody or antigen-binding fragment in nature. Moreover, the host cell may impart a post-translational modification (PTM; e.g., glycosylation or fucosylation) on the antibody or antigen-binding fragment that is not present in a native state of the antibody or antigen-binding fragment (or in a native state of a parent antibody from which the antibody or antigen binding fragment was engineered or derived). Such a PTM may result in a functional difference (e.g., reduced immunogenicity). Accordingly, an antibody or antigen-binding fragment of the present disclosure that is produced by a host cell as disclosed herein may include one or more post-translational modification that is distinct from the antibody (or parent antibody) in its native state (e.g., a human antibody produced by a CHO cell can comprise a more post-translational modification that is distinct from the antibody when isolated from the human and/or produced by the native human B cell or plasma cell). Insect cells useful expressing a binding protein of the present disclosure are known in the art and include, for example, Spodoptera frugipera Sf9 cells, Trichoplusia ni BTI-TN5B1-4 cells, and Spodoptera frugipera SfSWT01 “Mimic ^TM ” cells. See, e.g., Palmberger et al., J. Biotechnol.153(3-4):160-166 (2011). Numerous baculoviral strains have been identified which may be used in conjunction with insect cells, particularly for transfection of Spodoptera frugiperda cells. Eukaryotic microbes such as filamentous fungi or yeast are also suitable hosts for cloning or expressing protein-encoding vectors, and include fungi and yeast strains with “humanized” glycosylation pathways, resulting in the production of an antibody with a partially or fully human glycosylation pattern. See Gerngross, Nat. Biotech.22:1409-1414 (2004); Li et al., Nat. Biotech.24:210-215 (2006). Plant cells can also be utilized as hosts for expressing a binding protein of the present disclosure. For example, PLANTIBODIES™ technology (described in, for example, U.S. Pat. Nos.5,959,177; 6,040,498; 6,420,548; 7,125,978; and 6,417,429) employs transgenic plants to produce antibodies. In certain embodiments, the host cell comprises a mammalian cell. In particular embodiments, the host cell is a CHO cell, a HEK293 cell, a PER.C6 cell, a Y0 cell, a Sp2/0 cell, a NS0 cell, a human liver cell, a myeloma cell, or a hybridoma cell. In a related aspect, the present disclosure provides methods for producing an antibody, or antigen-binding fragment, wherein the methods comprise culturing a host cell of the present disclosure under conditions and for a time sufficient to produce the antibody, or the antigen-binding fragment. Methods useful for isolating and purifying recombinantly produced antibodies, by way of example, may include obtaining supernatants from suitable host cell/vector systems that secrete the recombinant antibody into culture media and then concentrating the media using a commercially available filter. Following concentration, the concentrate may be applied to a single suitable purification matrix or to a series of suitable matrices, such as an affinity matrix or an ion exchange resin. One or more reverse phase HPLC steps may be employed to further purify a recombinant polypeptide. These purification methods may also be employed when isolating an immunogen from its natural environment. Methods for large scale production of one or more of the isolated/recombinant antibody described herein include batch cell culture, which is monitored and controlled to maintain appropriate culture conditions. Purification of soluble antibodies may be performed according to methods described herein and known in the art and that comport with laws and guidelines of domestic and foreign regulatory agencies. Compositions Also provided herein are compositions that comprise any one or more of the presently disclosed antibodies, antigen-binding fragments, polynucleotides, vectors, or host cells, singly or in any combination, and can further comprise a pharmaceutically acceptable carrier, excipient, or diluent. Carriers, excipients, and diluents are discussed in further detail herein. In certain embodiments, a composition comprises a plurality of an antibody and/or an antigen-binding fragment of the present disclosure, wherein one or more antibody or antigen-binding fragment does not comprise a lysine residue at the C- terminal end of the heavy chain, CH1-CH3, or Fc polypeptide, and wherein one or more antibody or antigen-binding fragment comprises a lysine residue at the C-terminal end of the heavy chain, CH1-CH3, or Fc polypeptide. In certain embodiments, a composition comprises two or more different antibodies or antigen-binding fragments, which are optionally antibodies or antigen- bindign fragments according to the present disclosure. In certain embodiments, antibodies or antigen-binding fragments to be used in a combination each independently have one or more of the following characteristics: neutralize naturally occurring SARS-CoV-2 variants; do not compete with one another for Spike protein binding; bind distinct Spike protein epitopes; have a reduced formation of resistance to SARS-CoV-2; when in a combination, have a reduced formation of resistance to SARS- CoV-2; potently neutralize live SARS-CoV-2 virus; exhibit additive or synergistic effects on neutralization of live SARS-CoV-2 virus when used in combination; exhibit effector functions; are protective in relevant animal model(s) of infection; are capable of being produced in sufficient quantities for large-scale production. In certain embodiments, antibodies or antigen-binding fragments to be used in a combination each independently have one or more of the following characteristics: neutralize one, two, three, four, five, or more naturally occurring sarbecovirus variants; do not compete with one another for Spike protein binding; bind distinct sarbecovirus Spike protein epitopes; have a reduced formation of resistance to sarbecovirus; when in a combination, have a reduced formation of resistance to sarbecovirus; potently neutralize one, two, three, four, five or more live sarbecoviruses; exhibit additive or synergistic effects on neutralization of one, two, three, four, five or more or more live sarbecoviruses when used in combination; exhibit effector functions; are protective in relevant animal model(s) of infection; are capable of being produced in sufficient quantities for large-scale production. In certain embodiments, a composition comprises two or more different antibodies or antigen-binding fragments according to the present disclosure. In certain embodiments, a composition comprises a first vector comprising a first plasmid, and a second vector comprising a second plasmid, wherein the first plasmid comprises a polynucleotide encoding a heavy chain, VH, or VH+CH1, and a second plasmid comprises a polynucleotide encoding the cognate light chain, VL, or VL+CL of the antibody or antigen-binding fragment thereof. In certain embodiments, a composition comprises a polynucleotide (e.g., mRNA) coupled to a suitable delivery vehicle or carrier. In certain embodiments, a composition comprises a first polynucleotide (e.g., mRNA) encoding an antibody heavy chain, a VH, or a Fd (VH + CH1), and a second polynucleotide (e.g., mRNA) encoding the cognate antibody light chain, VL, or VL+CL. In one example, a composition can comprise a first polynucleotide (e.g., mRNA) encoding an antibody heavy chain comprising the VH set forth in SEQ ID NO.: 135 and a second polynucleotide (e.g., mRNA) encoding an antibody light chain comprising the VL set forth in SEQ ID NO.:113. In one example, a composition can comprise a first polynucleotide (e.g., mRNA) encoding an antibody heavy chain comprising the HCDRs (e.g., IMGT) of the VH set forth in SEQ ID NO.: 135 and a second polynucleotide (e.g., mRNA) encoding an antibody light chain comprising the LCDRs (e.g., IMGT) of the VL set forth in SEQ ID NO.:113. Exemplary vehicles or carriers for administration to a human subject include a lipid or lipid-derived delivery vehicle, such as a liposome, solid lipid nanoparticle, oily suspension, submicron lipid emulsion, lipid microbubble, inverse lipid micelle, cochlear liposome, lipid microtubule, lipid microcylinder, or lipid nanoparticle (LNP) or a nanoscale platform (see, e.g., Li et al. Wilery Interdiscip Rev. Nanomed Nanobiotechnol.11(2):e1530 (2019)). Principles, reagents, and techniques for designing appropriate mRNA and and formulating mRNA-LNP and delivering the same are described in, for example, Pardi et al. (J Control Release 217345-351 (2015)); Thess et al. (Mol Ther 23: 1456-1464 (2015)); Thran et al. (EMBO Mol Med 9(10):1434-1448 (2017); Kose et al. (Sci. Immunol.4 eaaw6647 (2019); and Sabnis et al. (Mol. Ther.26:1509-1519 (2018)), which techniques, include capping, codon optimization, nucleoside modification, purification of mRNA, incorporation of the mRNA into stable lipid nanoparticles (e.g., ionizable cationic lipid/phosphatidylcholine/cholesterol/PEG-lipid; ionizable lipid:distearoyl PC:cholesterol:polyethylene glycol lipid), and subcutaneous, intramuscular (e.g., deltoid, gluteal, dorsogluteal, thigh, anterolateral thigh), intradermal, intravenous, intraperitoneal, and intratracheal administration of the same, are incorporated herein by reference. Methods and Uses Also provided herein are methods for use of an antibody or antigen-binding fragment, nucleic acid, vector, cell, or composition of the present disclosure in the diagnosis of a sarbecovirus infection, such as a SARS-CoV-2 infection (e.g., in a human subject, or in a sample obtained from a human subject). Methods of diagnosis (e.g., in vitro, ex vivo) may include contacting an antibody, antibody fragment (e.g., antigen binding fragment) with a sample. Such samples may be isolated from a subject, for example an isolated tissue sample taken from, for example, nasal passages, sinus cavities, salivary glands, lung, liver, pancreas, kidney, ear, eye, placenta, alimentary tract, heart, ovaries, pituitary, adrenals, thyroid, brain, skin or blood. The methods of diagnosis may also include the detection of an antigen/antibody complex, in particular following the contacting of an antibody or antibody fragment with a sample. Such a detection step can be performed at the bench, i.e., without any contact to the human or animal body. Examples of detection methods are well-known to the person skilled in the art and include, e.g., ELISA (enzyme-linked immunosorbent assay), including direct, indirect, and sandwich ELISA. Also provided herein are methods of treating a subject using an antibody or antigen-binding fragment of the present disclosure, or a composition comprising the same, wherein the subject has, is believed to have, or is at risk for having an infection by a sarbecorvirus, such as SARS-CoV-2. "Treat," "treatment," or "ameliorate" refers to medical management of a disease, disorder, or condition of a subject (e.g., a human or non-human mammal, such as a primate, horse, cat, dog, goat, mouse, or rat). In general, an appropriate dose or treatment regimen comprising an antibody or composition of the present disclosure is administered in an amount sufficient to elicit a therapeutic or prophylactic benefit. Therapeutic or prophylactic/preventive benefit includes improved clinical outcome; lessening or alleviation of symptoms associated with a disease; decreased occurrence of symptoms; improved quality of life; longer disease-free status; diminishment of extent of disease, stabilization of disease state; delay or prevention of disease progression; remission; survival; prolonged survival; or any combination thereof. In certain embodiments, therapeutic or prophylactic/preventive benefit includes reduction or prevention of hospitalization for treatment of a sarbecovirus infection, such as a SARS-CoV-2 infection (i.e., in a statistically significant manner). In certain embodiments, therapeutic or prophylactic/preventive benefit includes a reduced duration of hospitalization for treatment of a sarbecovirus infection, such as a SARS-CoV-2 infection (i.e., in a statistically significant manner). In certain embodiments, therapeutic or prophylactic/preventive benefit includes a reduced or abrogated need for respiratory intervention, such as intubation and/or the use of a respirator device. In certain embodiments, therapeutic or prophylactic/preventive benefit includes reversing a late- stage disease pathology and/or reducing mortality. A "therapeutically effective amount" or "effective amount" of an antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition of this disclosure refers to an amount of the composition or molecule sufficient to result in a therapeutic effect, including improved clinical outcome; lessening or alleviation of symptoms associated with a disease; decreased occurrence of symptoms; improved quality of life; longer disease-free status; diminishment of extent of disease, stabilization of disease state; delay of disease progression; remission; survival; or prolonged survival in a statistically significant manner. When referring to an individual active ingredient, administered alone, a therapeutically effective amount refers to the effects of that ingredient or cell expressing that ingredient alone. When referring to a combination, a therapeutically effective amount refers to the combined amounts of active ingredients or combined adjunctive active ingredient with a cell expressing an active ingredient that results in a therapeutic effect, whether administered serially, sequentially, or simultaneously. A combination may comprise, for example, two different antibodies that specifically bind a SARS-CoV-2 antigen, which in certain embodiments, may be the same or different SARS-CoV-2 antigen, and/or can comprise the same or different epitopes. Accordingly, in certain embodiments, methods are provided for treating a sarbecovirus infection, such as a SARS-CoV-2 infection, in a subject, wherein the methods comprise administering to the subject an effective amount of an antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition as disclosed herein. Subjects that can be treated by the present disclosure are, in general, human and other primate subjects, such as monkeys and apes for veterinary medicine purposes. Other model organisms, such as mice and rats, may also be treated according to the present disclosure. In any of the aforementioned embodiments, the subject may be a human subject. The subjects can be male or female and can be any suitable age, including infant, juvenile, adolescent, adult, and geriatric subjects. A number of criteria are believed to contribute to high risk for severe symptoms or death associated with a SARS CoV-2 infection. These include, but are not limited to, age, occupation, general health, pre-existing health conditions, and lifestyle habits. In some embodiments, a subject treated according to the present disclosure comprises one or more risk factors. In certain embodiments, a human subject treated according to the present disclosure is an infant, a child, a young adult, an adult of middle age, or an elderly person. In certain embodiments, a human subject treated according to the present disclosure is less than 1 year old, or is 1 to 5 years old, or is between 5 and 125 years old (e.g., 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, or 125 years old, including any and all ages therein or therebetween). In certain embodiments, a human subject treated according to the present disclosure is 0- 19 years old, 20-44 years old, 45-54 years old, 55-64 years old, 65-74 years old, 75-84 years old, or 85 years old, or older. Persons of middle, and especially of elderly age are believed to be at particular risk. In particular embodiments, the human subject is 45-54 years old, 55-64 years old, 65-74 years old, 75-84 years old, or 85 years old, or older. In some embodiments, the human subject is male. In some embodiments, the human subject is female. In certain embodiments, a human subject treated according to the present disclosure is a resident of a nursing home or a long-term care facility, is a hospice care worker, is a healthcare provider or healthcare worker, is a first responder, is a family member or other close contact of a subject diagnosed with or suspected of having a SARS-CoV-2 infection, is overweight or clinically obese, is or has been a smoker, has or had chronic obstructive pulmonary disease (COPD), is asthmatic (e.g., having moderate to severe asthma), has an autoimmune disease or condition (e.g., diabetes), and/or has a compromised or depleted immune system (e.g., due to AIDS/HIV infection, a cancer such as a blood cancer, a lymphodepleting therapy such as a chemotherapy, a bone marrow or organ transplantation, or a genetic immune condition), has chronic liver disease, has cardiovascular disease, has a pulmonary or heart defect, works or otherwise spends time in close proximity with others, such as in a factory, shipping center, hospital setting, or the like. In certain embodiments, a subject treated according to the present disclosure has received a vaccine for SARS-CoV-2 and the vaccine is determined to be ineffective, e.g., by post-vaccine infection or symptoms in the subject, by clinical diagnosis or scientific or regulatory criteria. In certain embodiments, treatment is administered as peri-exposure prophylaxis. In certain embodiments, treatment is administered to a subject with mild- to-moderate disease, which may be in an outpatient setting. In certain embodiments, treatment is administered to a subject with moderate-to-severe disease, such as requiring hospitalization. Typical routes of administering the presently disclosed compositions thus include, without limitation, oral, topical, transdermal, inhalation, parenteral, sublingual, buccal, rectal, vaginal, and intranasal. The term "parenteral", as used herein, includes subcutaneous injections, intravenous, intramuscular, intrasternal injection or infusion techniques. In certain embodiments, administering comprises administering by a route that is selected from oral, intravenous, parenteral, intragastric, intrapleural, intrapulmonary, intrarectal, intradermal, intraperitoneal, intratumoral, subcutaneous, topical, transdermal, intracisternal, intrathecal, intranasal, and intramuscular. In particular embodiments, a method comprises orally administering the antibody, antigen- binding fragment, polynucleotide, vector, host cell, or composition to the subject. Pharmaceutical compositions according to certain embodiments of the present invention are formulated so as to allow the active ingredients contained therein to be bioavailable upon administration of the composition to a patient. Compositions that will be administered to a subject or patient may take the form of one or more dosage units, where for example, a tablet may be a single dosage unit, and a container of a herein described an antibody or antigen-binding in aerosol form may hold a plurality of dosage units. Actual methods of preparing such dosage forms are known, or will be apparent, to those skilled in this art; for example, see Remington: The Science and Practice of Pharmacy, 20th Edition (Philadelphia College of Pharmacy and Science, 2000). The composition to be administered will, in any event, contain an effective amount of an antibody or antigen-binding fragment, polynucleotide, vector, host cell, , or composition of the present disclosure, for treatment of a disease or condition of interest in accordance with teachings herein. A composition may be in the form of a solid or liquid. In some embodiments, the carrier(s) are particulate, so that the compositions are, for example, in tablet or powder form. The carrier(s) may be liquid, with the compositions being, for example, an oral oil, injectable liquid or an aerosol, which is useful in, for example, inhalatory administration. When intended for oral administration, the pharmaceutical composition is preferably in either solid or liquid form, where semi solid, semi liquid, suspension and gel forms are included within the forms considered herein as either solid or liquid. As a solid composition for oral administration, the pharmaceutical composition may be formulated into a powder, granule, compressed tablet, pill, capsule, chewing gum, wafer or the like. Such a solid composition will typically contain one or more inert diluents or edible carriers. In addition, one or more of the following may be present: binders such as carboxymethylcellulose, ethyl cellulose, microcrystalline cellulose, gum tragacanth or gelatin; excipients such as starch, lactose or dextrins, disintegrating agents such as alginic acid, sodium alginate, Primogel, corn starch and the like; lubricants such as magnesium stearate or Sterotex; glidants such as colloidal silicon dioxide; sweetening agents such as sucrose or saccharin; a flavoring agent such as peppermint, methyl salicylate or orange flavoring; and a coloring agent. When the composition is in the form of a capsule, for example, a gelatin capsule, it may contain, in addition to materials of the above type, a liquid carrier such as polyethylene glycol or oil. The composition may be in the form of a liquid, for example, an elixir, syrup, solution, emulsion or suspension. The liquid may be for oral administration or for delivery by injection, as two examples. When intended for oral administration, preferred compositions contain, in addition to the present compounds, one or more of a sweetening agent, preservatives, dye/colorant and flavor enhancer. In a composition intended to be administered by injection, one or more of a surfactant, preservative, wetting agent, dispersing agent, suspending agent, buffer, stabilizer and isotonic agent may be included. Liquid pharmaceutical compositions, whether they be solutions, suspensions or other like form, may include one or more of the following adjuvants: sterile diluents such as water for injection, saline solution, preferably physiological saline, Ringer’s solution, isotonic sodium chloride, fixed oils such as synthetic mono or diglycerides which may serve as the solvent or suspending medium, polyethylene glycols, glycerin, propylene glycol or other solvents; antibacterial agents such as benzyl alcohol or methyl paraben; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediaminetetraacetic acid; buffers such as acetates, citrates or phosphates and agents for the adjustment of tonicity such as sodium chloride or dextrose. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic. Physiological saline is a preferred adjuvant. An injectable pharmaceutical composition is preferably sterile. A liquid composition intended for either parenteral or oral administration should contain an amount of an antibody or antigen-binding fragment as herein disclosed such that a suitable dosage will be obtained. Typically, this amount is at least 0.01% of the antibody or antigen-binding fragment in the composition. When intended for oral administration, this amount may be varied to be between 0.1 and about 70% of the weight of the composition. Certain oral pharmaceutical compositions contain between about 4% and about 75% of the antibody or antigen-binding fragment. In certain embodiments, pharmaceutical compositions and preparations according to the present invention are prepared so that a parenteral dosage unit contains between 0.01 to 10% by weight of antibody or antigen-binding fragment prior to dilution. The composition may be intended for topical administration, in which case the carrier may suitably comprise a solution, emulsion, ointment or gel base. The base, for example, may comprise one or more of the following: petrolatum, lanolin, polyethylene glycols, bee wax, mineral oil, diluents such as water and alcohol, and emulsifiers and stabilizers. Thickening agents may be present in a composition for topical administration. If intended for transdermal administration, the composition may include a transdermal patch or iontophoresis device. The pharmaceutical composition may be intended for rectal administration, in the form, for example, of a suppository, which will melt in the rectum and release the drug. The composition for rectal administration may contain an oleaginous base as a suitable nonirritating excipient. Such bases include, without limitation, lanolin, cocoa butter and polyethylene glycol. A composition may include various materials which modify the physical form of a solid or liquid dosage unit. For example, the composition may include materials that form a coating shell around the active ingredients. The materials that form the coating shell are typically inert, and may be selected from, for example, sugar, shellac, and other enteric coating agents. Alternatively, the active ingredients may be encased in a gelatin capsule. The composition in solid or liquid form may include an agent that binds to the antibody or antigen-binding fragment of the disclosure and thereby assists in the delivery of the compound. Suitable agents that may act in this capacity include monoclonal or polyclonal antibodies, one or more proteins or a liposome. The composition may consist essentially of dosage units that can be administered as an aerosol. The term aerosol is used to denote a variety of systems ranging from those of colloidal nature to systems consisting of pressurized packages. Delivery may be by a liquefied or compressed gas or by a suitable pump system that dispenses the active ingredients. Aerosols may be delivered in single phase, bi phasic, or tri phasic systems in order to deliver the active ingredient(s). Delivery of the aerosol includes the necessary container, activators, valves, subcontainers, and the like, which together may form a kit. One of ordinary skill in the art, without undue experimentation, may determine preferred aerosols. It will be understood that compositions of the present disclosure also encompass carrier molecules for polynucleotides, as described herein (e.g., lipid nanoparticles, nanoscale delivery platforms, and the like). The pharmaceutical compositions may be prepared by methodology well known in the pharmaceutical art. For example, a composition intended to be administered by injection can be prepared by combining a composition that comprises an antibody, antigen-binding fragment thereof, or antibody conjugate as described herein and optionally, one or more of salts, buffers and/or stabilizers, with sterile, distilled water so as to form a solution. A surfactant may be added to facilitate the formation of a homogeneous solution or suspension. Surfactants are compounds that non-covalently interact with the peptide composition so as to facilitate dissolution or homogeneous suspension of the antibody or antigen-binding fragment thereof in the aqueous delivery system. In general, an appropriate dose and treatment regimen provide the composition(s) in an amount sufficient to provide therapeutic and/or prophylactic benefit (such as described herein, including an improved clinical outcome (e.g., a decrease in frequency, duration, or severity of diarrhea or associated dehydration, or inflammation, or longer disease-free and/or overall survival, or a lessening of symptom severity). For prophylactic use, a dose should be sufficient to prevent, delay the onset of, or diminish the severity of a disease associated with disease or disorder. Prophylactic benefit of the compositions administered according to the methods described herein can be determined by performing pre-clinical (including in vitro and in vivo animal studies) and clinical studies and analyzing data obtained therefrom by appropriate statistical, biological, and clinical methods and techniques, all of which can readily be practiced by a person skilled in the art. Compositions are administered in an effective amount (e.g., to treat a SARS- CoV-2 infection), which will vary depending upon a variety of factors including the activity of the specific compound employed; the metabolic stability and length of action of the compound; the age, body weight, general health, sex, and diet of the subject; the mode and time of administration; the rate of excretion; the drug combination; the severity of the particular disorder or condition; and the subject undergoing therapy. In certain embodiments, tollowing administration of therapies according to the formulations and methods of this disclosure, test subjects will exhibit about a 10% up to about a 99% reduction in one or more symptoms associated with the disease or disorder being treated as compared to placebo-treated or other suitable control subjects. Generally, a therapeutically effective daily dose of an antibody or antigen binding fragment is (for a 70 kg mammal) from about 0.001 mg/kg (i.e., 0.07 mg) to about 100 mg/kg (i.e., 7.0 g); preferably a therapeutically effective dose is (for a 70 kg mammal) from about 0.01 mg/kg (i.e., 0.7 mg) to about 50 mg/kg (i.e., 3.5 g); more preferably a therapeutically effective dose is (for a 70 kg mammal) from about 1 mg/kg (i.e., 70 mg) to about 25 mg/kg (i.e., 1.75 g). For polynucleotides, vectors, host cells, and related compositions of the present disclosure, a therapeutically effective dose may be different than for an antibody or antigen-binding fragment. In certain embodiments, a method comprises administering the antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition to the subject at 2, 3, 4, 5, 6, 7, 8, 9, 10 times, or more. In certain embodiments, a method comprises administering the antibody, antigen-binding fragment, or composition to the subject a plurality of times, wherein a second or successive administration is performed at about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 24, about 48, about 74, about 96 hours, or more, following a first or prior administration, respectively. In certain embodiments, a method comprises administering the antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition at least one time prior to the subject being infected by a sarbecovirus, such as SARS-CoV-2. In some embodiments, an antibody or antigen-binding fragment, or a polynucleotide or vector or host cell encoding the same, or a composition encoding the antibody, antigen-binding fragment, polynucleotide, vector, or host cell, or a composition comprising two or more different antibodies or antigen-binding fragments (e.g., an antibody or antigen-binding fragment of the present disclosure and an antibody or antigen-binding fragment comprising the six CDRs, optionally the VH and the VL, and further optionally the heavy and light chains, of sotrovimab or S309) is administered intramuscularly. In some embodiments, administration comprises administration to a deltoid muscle, a gluteal muscle (e.g., a dorsogluteal muscle), a thigh muscle (e.g., an anterolateral thigh muscle), or any combination thereof. In some embodiments, administration comprises one, two, three, four, five, six, seven, eight, nine, or ten administrations, e.g. to a deltoid, thigh, and/or gluteal muscle. In particular embodiments, a single dose of an antibody or antigen-binding fragment comprises about 500 mg of a liquid composition comprising about 62.5 mg/mL or about 100 mg/mL of the antibody or antige-binding fragment, e.g., administered intramuscularly, e.g., administered into a dorsogluteal muscle, into an anterolateral thigh muscle, into a deltoid muscle, or any combination thereof. In some embodiments, a single dose does not exceed 2.5 mL/injection (e.g., into a deltoid muscle) or does not exceed 5 mL/injection (e.g., into a thigh and/or gluteal muscle).Compositions comprising an antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition of the present disclosure may also be administered simultaneously with, prior to, or after administration of one or more other therapeutic agents. Such combination therapy may include administration of a single pharmaceutical dosage formulation which contains a compound of the invention and one or more additional active agents, as well as administration of compositions comprising an antibody or antigen-binding fragment of the disclosure and each active agent in its own separate dosage formulation. For example, an antibody or antigen-binding fragment thereof as described herein and the other active agent can be administered to the patient together in a single oral dosage composition such as a tablet or capsule, or each agent administered in separate oral dosage formulations. Similarly, an antibody or antigen-binding fragment as described herein and the other active agent can be administered to the subject together in a single parenteral dosage composition such as in a saline solution or other physiologically acceptable solution, or each agent administered in separate parenteral dosage formulations. Where separate dosage formulations are used, the compositions comprising an antibody or antigen-binding fragment and one or more additional active agents can be administered at essentially the same time, i.e., concurrently, or at separately staggered times, i.e., sequentially and in any order; combination therapy is understood to include all these regimens. In certain embodiments, a combination therapy is provided that comprises one or more anti-sarbecovirus antibody, such as an anti-SARS-CoV-2 antibody, (or one or more nucleic acid, host cell, vector, or composition) of the present disclosure and one or more anti-inflammatory agent and/or one or more anti-viral agent. In particular embodiments, the one or more anti-inflammatory agent comprises a corticosteroid such as, for example, dexamethasone, prednisone, or the like. In some embodiments, the one or more anti-inflammatory agents comprise a cytokine antagonist such as, for example, an antibody that binds to IL6 (such as siltuximab), or to IL-6R (such as tocilizumab), or to IL-1β, IL-7, IL-8, IL-9, IL-10, FGF, G-CSF, GM-CSF, IFN-γ, IP-10, MCP-1, MIP- 1A, MIP1-B, PDGR, TNF-α, or VEGF. In some embodiments, anti-inflammatory agents such as leronlimab, ruxolitinib and/or anakinra are used. In some embodiments, the one or more anti-viral agents comprise nucleotide analogs or nucelotide analog prodrugs such as, for example, remdesivir, sofosbuvir, acyclovir, and zidovudine. In particular embodiments, an anti-viral agent comprises lopinavir, ritonavir, favipiravir, or any combination thereof. Other anti-inflammatory agents for use in a combination therapy of the present disclosure include non-steroidal anti-inflammatory drugs (NSAIDS). It will be appreciated that in such a combination therapy, the one or more antibody (or one or more nucleic acid, host cell, vector, or composition) and the one or more anti-inflammatory agent and/or one or the more antiviral agent can be administered in any order and any sequence, or together. In some embodiments, an antibody (or one or more nucleic acid, host cell, vector, or composition) is administered to a subject who has previously received one or more anti-inflammatory agent and/or one or more antiviral agent. In some embodiments, one or more anti-inflammatory agent and/or one or more antiviral agent is administered to a subject who has previously received an antibody (or one or more nucleic acid, host cell, vector, or composition). In certain embodiments, a combination therapy is provided that comprises two or more anti-sarbecovirus antibodies of the present disclosure, such as two or more anti- SARS-CoV-2 antibodies. A method can comprise administering a first antibody to a subject who has received a second antibody, or can comprise administering two or more antibodies together. For example, in particular embodiments, a method is provided that comprises administering to the subject (a) a first antibody or antigen-binding fragment, when the subject has received a second antibody or antigen-binding fragment; (b) the second antibody or antigen-binding fragment, when the subject has received the first antibody or antigen-binding fragment; or (c) the first antibody or antigen-binding fragment, and the second antibody or antigen-binding fragment. In a related aspect, uses of the presently disclosed antibodies, antigen-binding fragments, vectors, host cells, and compositions are provided. In certain embodiments, an antibody, antigen-binding fragment, polynucleotide, vector, host cell, or composition is provided for use in a method of treating a SARS- CoV-2 infection in a subject. In certain embodiments, an antibody, antigen-binding fragment, or composition is provided for use in a method of manufacturing or preparing a medicament for treating a sarbecovirus infection, such as a SARS-CoV-2 infection, in a subject. Table 3. Sequences The present disclosure also provides the following non-limiting, numbered Embodiments, which may be referenced by number in other Embodiments: Embodiment 1. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising, in a heavy chain variable domain (VH), a complementarity determining region (CDR)H1, a CDRH2, and/or a CDRH3 of the VH amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, 98, 101, 109, 116, 120, 130, 131, and 135, and/or, in a light chain variable domain (VL), a CDRL1, a CDRL2, and/or a CDRL3 of the VL amino acid sequence set forth in any one of SEQ ID NOs.:72, 76, 80, 84, 88, 92, 96, 100, 105, 113, 118, 124, and 132. Embodiment 2. The antibody or antigen-binding fragment of Embodiment 1, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, 98, 101, 109, 116, 120, 130, 131, and 135, and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in any one of SEQ ID NOs.:72, 76, 80, 84, 88, 92, 96, 100, 105, 113, 118, 124, and 132. Embodiment 3. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:70 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:72.Embodiment 4. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:74 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:76. Embodiment 5. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:78 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:80. Embodiment 6. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:82 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:84. Embodiment 7. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:86 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:88. Embodiment 8. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:90 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:92. Embodiment 9. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:94 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:96. Embodiment 10. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:98 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:100. Embodiment 11. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:101 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:105. Embodiment 12. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:109 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113. Embodiment 13. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:116 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:118. Embodiment 14. The antibody or antigen-binding fragment of Embodiment 1 or Embodiment 2, comprising: (1) a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:120 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:124; (2) a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:130 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:105; (3) a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:131 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113; (4) a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:131 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:132; or (5) a CDRH1, a CDRH2, and a CDRH3 of the VH amino acid sequence set forth in SEQ ID NO.:135 and a CDRL1, a CDRL2, and a CDRL3 of the VL amino acid sequence set forth in SEQ ID NO.:113. Embodiment 15. The antibody or antigen-binding fragment of any one of Embodiments 1-14, wherein the CDRs are according to IMGT numbering, Kabat numbering, Chothia numbering, AHo numbering, North numbering, Contact numbering, CCG numbering, EU numbering, Martin (Enhanced Chothia) numbering, or a hybrid definition of two or more of the foregoing numbering schemes, wherein, optionally, the antibody or antigen-binding fragment comprises, in a VH, the amino acid sequences GGIDNTYT (SEQ ID NO.:138), ILMSGWA (SEQ ID NO.:136), and ARGFHSDYYGWGDDDAFDF (SEQ ID NO.:137), and in a VL, the amino acid sequences NSNIGAGYD (SEQ ID NO.:43), GNS (SEQ ID NO.:44), and QSYDSSLSEPTWV (SEQ ID NO.:139). Embodiment 16. The antibody or antigen-binding fragment of any one of Embodiments 1-15, wherein the CDRs are according to IMGT numbering. Embodiment 17. The antibody or antigen-binding fragment of any one of Embodiments 1-16, which is capable of binding to a surface glycoprotein of a SARS- CoV-2, a SARS-CoV, a SARS-CoV-2 G504D variant, a SARS-CoV-2 B.1.617.2 variant, or any combination thereof. Embodiment 18. The antibody or antigen-binding fragment of any one of Embodiments 1-17, which is capable of binding to a surface glycoprotein of a sarbecovirus of clade 1a, of clade 1b, of clade 2, and/or of clade 3. Embodiment 19. The antibody or antigen-binding fragment of any one of Embodiments 1-18, wherein the VH comprises or consists of an amino acid sequence having at least 85% (e.g., 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%) identity to the amino acid sequence set forth in any one of SEQ ID NOs.:70, 74, 78, 82, 86, 90, 94, 98, 101, 109, 116, 120, 130, 131, and 135, and the VL comprises or consists of an amino acid sequence having at least 85% (e.g., 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%) identity to the amino acid sequence set forth in any one of SEQ ID NOs.:72, 76, 80, 84, 88, 92, 96, 100, 105, 113, 118, 124, and 132. Embodiment 20. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:70 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:72. Embodiment 21. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:74 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:76. Embodiment 22. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:78 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:80. Embodiment 23. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:82 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:84. Embodiment 24. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:86 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:88. Embodiment 25. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:90 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:92. Embodiment 26. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:94 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:96. Embodiment 27. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:98 and the VL comprises or consists of an amino acid sequence having at least 85% identity to, or comprising or consisting of, the amino acid sequence set forth in SEQ ID NO.:100. Embodiment 28. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:105. Embodiment 29. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:105. Embodiment 30. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:105. Embodiment 31. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:105. Embodiment 32. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:101 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:105. Embodiment 33. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 34. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 35. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 36. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 37. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:109 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 38. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:118. Embodiment 39. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:118. Embodiment 40. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:118. Embodiment 41. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:118. Embodiment 42. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:116 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:118. Embodiment 43. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein: (1) the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:124; (2) the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:105; (3) the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113; (4) the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:132; or (5) the VH comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 85% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 44. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein: (1) the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:124; (2) the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:105; (3) the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113; (4) the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:132; or (5) the VH comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 90% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 45. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein: (1) the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:124; (2) the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:105; (3) the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113; (4) the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:132; or (5) the VH comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 95% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 46. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein: (1) the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:124; (2) the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:105; (3) the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113; (4) the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:132; or (5) the VH comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of an amino acid sequence having at least 97% identity to the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 47. The antibody or antigen-binding fragment of any one of Embodiments 1-19, wherein: (1) the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:120 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:124; (2) the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:130 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:105; (3) the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113; (4) the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:131 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:132; or (5) the VH comprises or consists of the amino acid sequence set forth in SEQ ID NO.:135 and the VL comprises or consists of the amino acid sequence set forth in SEQ ID NO.:113. Embodiment 48. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIFNTYTISWVRQAPGQGLEWMG RIILMSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NSNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:70); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSFDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:72). Embodiment 49. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN GNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:74); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:76). Embodiment 50. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILTSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGY NGNYYGWGDDDAFDNWGQGTLVTVSS (SEQ ID NO.:78); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRRSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSGPNW VFGGGTKLTVL (SEQ ID NO.:80). Embodiment 51. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGSHNTYTISWVRQAPGQGLEWMG RIILMSGMANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:82); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPQWV FGGGTKLTVL (SEQ ID NO.:84). Embodiment 52. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILSSGLANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN GNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:86); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCNGSNSNIGVGYDVHWYQQLPGTAPKLLIV GNSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSGPNW VFGGGTKLTVL (SEQ ID NO.:88). Embodiment 53. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGILNTYTISWVRQAPGQGLEWMG RIILRSGMTNYAQNIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDNWGQGTLVTVSS (SEQ ID NO.:90); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCNGSNSNIGVGYDVHWYQQLPGTAPKLLIV GNSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSGPNW VFGGGTKLTVL (SEQ ID NO.:92). Embodiment 54. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILMSGSANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NGNYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:94); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSDPNW VFGGGTKLTVL (SEQ ID NO.:96). Embodiment 55. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIFNTYTISWVRQAPGQGLEWMG RIILNSGFANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFS GRYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:98); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGTNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRASGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSDPIWV FGGGTKLTVL (SEQ ID NO.:100). Embodiment 56. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:101) ; and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:105). Embodiment 57. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILMSGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF NSNYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:109) ; and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). Embodiment 58. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:116) ; and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL (SEQ ID NO.:76). Embodiment 59. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: (1) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGISNTYTISWVRQAPGQGLEWMG RIILSSGLANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:120); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGVGYDVHWYQQLPGTAPKLLIV GQSGRHSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSGPNW VFGGGTKLTVL (SEQ ID NO.:124); (2) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRADYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN ANYYGFGDDDAFDIWGQGTLVTVSS (SEQ ID NO.:130); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSGSAPNW VFGGGTKLTVL(SEQ ID NO.:105); (3) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN SNYYGFGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:131); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113); or (4) a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDQTYTISWVRQAPGQGLEWMG RIILISGRANYAQKIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGFN SNYYGFGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:131); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GQSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:132). Embodiment 59a. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILMSGWANYAQTIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF HSDYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:135); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). Embodiment 60. The antibody or antigen-binding fragment of any one of Embodiments 1-59a, which is capable of neutralizing a SARS-CoV-2 infection in an in vitro model of infection and/or in an in vivo animal model of infection and/or in a human, wherein, optionally, the SARS-CoV-2 infection comprises a SARS-CoV-2 comprising the amino acid sequence according to SEQ ID NO.:3. Embodiment 61. The antibody or antigen-binding fragment of any one of Embodiments 1-60, which is (i) capable of binding to the surface glycoprotein of two or more (e.g., two, three, four, five, or more) sarbecoviruses; and/or (ii) capable of neutralizing an infection by two or more sarbecoviruses in an in vitro model of infection and/or in an in vivo animal model of infection and/or in a human. Embodiment 62. The antibody or antigen-binding fragment of any one of Embodiments 1-61, which is capable of binding to a surface glycoprotein of any one or more of (i)-(ix): (i) one or more sarbecovirus of Clade 1a, wherein the one or more sarbecovirus optionally comprises SARS-CoV, Rs3367, Rs4084, LYRa3, Rs4231, Rs4874, WIV1, or any combination thereof; (ii) one or more sarbecovirus of Clade 1b, wherein the one or more sarbecovirus comprises SARS-CoV-2 and, optionally, one or more of RatG13, PangGD, and PangGX; (iii) one or more sarbecovirus of Clade 2, wherein the one or more sarbecovirus comprises Rm1/2004, As6526, HKU3-12, Rp/Shaanxi2011, Cp/Yunnan2011, Rf4092, Rs4255, ZXC21, ZC45, YN2013, RMYN02, SC2018, Anlong112, YN2013, SC2011, ZC45, or any combination thereof; (iv) one or more sarbecovirus of Clade 3, wherein the one or more sarbecovirus optionally comprises BtKY72, BGR2008, or both; (iv) a variant of SEQ ID NO.:3 comprising: (iv)(a) a N501Y mutation; (iv)(b) a Y453F mutation; (iv)(c) a N439K mutation; (iv)(d) a K417V mutation; (iv)(e) a N501Y mutation, a K417N mutation, and a E484K mutation; and/or (iv)(f) a G504D mutation; (v) a SARS-CoV-2 B.1.351 variant; (vi) a SARS-CoV-2 B.1.429 variant; (vii) a SARS-CoV-2 P.1 variant; (viii) a SARS-CoV-2 B.1.1.222 variant; (ix) a SARS-CoV-2 B.1.617.2 variant. Embodiment 63. The antibody or antigen-binding fragment of any one of Embodiments 1-62, which is capable of binding to a surface glycoprotein of: (i) a SARS-CoV-2 Wuhan-Hu-1 (SEQ ID NO.:3); (ii) a SARS-CoV-2 B.1.1.7; (iii) a SARS- CoV-2 B.1.351; (iv) a SARS-CoV-2 variant P.1; (v) a SARS-CoV-2 variant B.1.429; (vi) a SARS-CoV; (vii) a WIV1; (viii) a PANG/GD; (ix) a PANG/GX; (x) a RatG13; (xi) a ZXC21; (xii) a ZC45; (xiii) a RmYN02; (xiv) a BGR2008; (xv) a BtkY72; (xvi) a SARS-CoV-2 B.1.617.2; (xvii) a SARS-CoV-2 G504D; or (xviii) any combination of (i)-(xvii). Embodiment 64. The antibody or antigen-binding fragment of any one of Embodiments 1-63, which is a IgG, IgA, IgM, IgE, or IgD isotype. Embodiment 65. The antibody or antigen-binding fragment of any one of Embodiments 1-34, which is an IgG isotype selected from IgG1, IgG2, IgG3, and IgG4 (optionally with a C-terminal lysine or a C-terminal glycine-lysine removed), and is optionally an IgG1 g1m, 17 allotype or an IgG1 g1m3 allotype. Embodiment 66. The antibody or antigen-binding fragment of any one of Embodiments 1-65, which is human, humanized, or chimeric. Embodiment 67. The antibody or antigen-binding fragment of any one of Embodiments 1-66, wherein the antibody, or the antigen-binding fragment, comprises a human antibody, a monoclonal antibody, a purified antibody, a single chain antibody, a Fab, a Fabʹ, a F(abʹ)2, a Fv, a scFv, or a scFab. Embodiment 68. The antibody or antigen-binding fragment of Embodiment 67, wherein the antibody or antigen-binding fragment comprises a scFv comprising more than one VH domain and more than one VL domain. Embodiment 69. The antibody or antigen-binding fragment of any one of Embodiments 1-68, wherein the antibody or antigen-binding fragment is a multi-specific antibody or antigen binding fragment. Embodiment 70. The antibody or antigen-binding fragment of Embodiment 69, wherein the antibody or antigen binding fragment is a bispecific antibody or antigen-binding fragment. Embodiment 71. The antibody or antigen-binding fragment of any one of Embodiments 1-70, wherein the antibody or antigen-binding fragment comprises a Fc polypeptide or a fragment thereof. Embodiment 72. The antibody or antigen-binding fragment of Embodiment 71, wherein the Fc polypeptide or fragment thereof comprises: (i) a mutation that enhances binding to a FcRn as compared to a reference Fc polypeptide that does not comprise the mutation; and/or (ii) a mutation that enhances binding to a FcγR as compared to a reference Fc polypeptide that does not comprise the mutation. Embodiment 73. The antibody or antigen-binding fragment of Embodiment 72, wherein the mutation that enhances binding to a FcRn comprises: M428L; N434S; N434H; N434A; N434S; M252Y; S254T; T256E; T250Q; P257I; Q311I; D376V; T307A; E380A; or any combination thereof. Embodiment 74. The antibody or antigen-binding fragment of Embodiment 72 or 73, wherein the mutation that enhances binding to FcRn comprises: (i) M428L/N434S; (ii) M252Y/S254T/T256E; (iii) T250Q/M428L; (iv) P257I/Q311I; (v) P257I/N434H; (vi) D376V/N434H; (vii) T307A/E380A/N434A; or (viii) any combination of (i)-(vii). Embodiment 75. The antibody or antigen-binding fragment of any one of Embodiments 72-74, wherein the mutation that enhances binding to FcRn comprises M428L/N434S. Embodiment 76. The antibody or antigen-binding fragment of any one of Embodiments 72-75, wherein the mutation that enhances binding to a FcγR comprises S239D; I332E; A330L; G236A; or any combination thereof. Embodiment 77. The antibody or antigen-binding fragment of any one of Embodiments 72-76, wherein the mutation that enhances binding to a FcγR comprises: (i) S239D/I332E; (ii) S239D/A330L/I332E; (iii) G236A/S239D/I332E; or (iv) G236A/A330L/I332E. Embodiment 78. The antibody or antigen-binding fragment of any one of Embodiments 1-77, comprising an IgG1 isotype, optionally an IgG1m3 allotype or an IgG1m17 allotype, comprising (according to EU numbering): (i) M428L and N434S mutations; (ii) G236A, L328V, and Q295E mutations; (iii) G236A, L328V, Q259E, M428L, and N434S mutations; (iv) G236A, L328V, Q295E, M428L, and N434S mutations, wherein the antibody or antigen-binding fragment is afucosylated; (v) G236A, R292P, and Y300L mutations; (vi) G236A, R292P, Y300L, M428L, and N434S mutations; (vii) G236A, A330L, I332E, M428L, and N434S mutations; (viii) a G236A mutation, optionally wherein the antibody or antigen-binding fragment is afucosylated; (ix) G236A, M428L, and N434S mutations, optionally wherein the antibody or antigen-binding fragment is afucosylated; (x) G236R and L328R mutations; or (xi) G236R, L328R, M428L, and N434S mutations. Embodiment 79. The antibody or antigen-binding fragment of Embodiment 78, comprising the VH amino acid sequence of SEQ ID NO.:101 and the VL amino acid sequence of SEQ ID NO.:105. Embodiment 80. The antibody or antigen-binding fragment of any one of Embodiments 1-79, which comprises a mutation that alters glycosylation, wherein the mutation that alters glycosylation comprises N297A, N297Q, or N297G, and/or which is aglycosylated and/or afucosylated. Embodiment 81. The antibody or antigen-binding fragment of any one of Embodiments 1-80, which is capable of activating a human FcγRIIa, a human FcγRIIIa, or both, when bound to a SARS-CoV-2 S protein expressed on a surface of a target cell, wherein, optionally: (i) the target cell comprises an EpiCHO cell; (ii) the human FcγRIIa comprises a H131 allele; (iii) the human FcγRIIIa comprises a V158 allele; and/or (iv) the human FcγRIIIa and/or the human FcγRIIa is expressed by a host cell, such as a Jurkat cell or a Natural Killer cell, and activation is determined using a NFAT-driven luciferase signal in the host cell. Embodiment 82. The antibody or antigen-binding fragment of any one of Embodiments 1-81, wherein the antibody or antigen-binding fragment is capable of inducing antibody-dependent cell-mediated cytotoxicity (ADCC) and/or antibody dependent cellular phagocytosis (ADCP) against a target cell infected by SARS-CoV-2. Embodiment 83. The antibody or antigen-binding fragment of any one of Embodiments 71-82, wherein the Fc polypeptide or fragment thereof comprises a L234A mutation and a L235A mutation. Embodiment 84. The antibody or antigen-binding fragment of any one of Embodiments 1-83, wherein the antibody or antigen-binding fragment is capable of binding to a SARS-CoV-2 S protein, as determined using biolayer interferometry. Embodiment 85. An isolated polynucleotide encoding the antibody or antigen-binding fragment of any one of Embodiments 1-84, or encoding a VH, a heavy chain, a VL, and/or a light chain of the antibody or the antigen-binding fragment. Embodiment 86. The polynucleotide of Embodiment 54, wherein the polynucleotide comprises deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), wherein the RNA optionally comprises messenger RNA (mRNA). Embodiment 87. The polynucleotide of Embodiment 85 or 86, which is codon-optimized for expression in a host cell. Embodiment 88. The polynucleotide of any one of Embodiments 85-87, comprising a polynucleotide having at least 50% identity to the polynucleotide sequence according to any one or more of SEQ ID NOs.: 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, or any combination thereof. Embodiment 89. A recombinant vector comprising the polynucleotide of any one of Embodiments 85-88. Embodiment 90. A host cell comprising the polynucleotide of any one of Embodiments 85-88 and/or the vector of Embodiment 89, wherein the polynucleotide is heterologous to the host cell. Embodiment 91. A human B cell comprising the polynucleotide of any one of Embodiments 85-88, wherein polynucleotide is heterologous to the human B cell and/or wherein the human B cell is immortalized. Embodiment 92. A composition comprising: (i) the antibody or antigen- binding fragment of any one of Embodiments 1-84; (ii) the polynucleotide of any one of Embodiments 85-88; (iii) the recombinant vector of Embodiment 89; (iv) the host cell of Embodiment 90; and/or (v) the human B cell of Embodiment 91; and a pharmaceutically acceptable excipient, carrier, or diluent. Embodiment 93. The composition of Embodiment 91, comprising two or more different antibodies or antigen-binding fragments, wherein each of the two or more different antibodies or antigen-binding fragments is different and is optionally independently according to of any one of Embodiments 1-84. Embodiment 94. The composition of Embodiment 92 or 93, further comprising an antibody or antigen-binding fragment comprising CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 amino acid sequences as set forth in SEQ ID NOs.:23-25 and 27-29, respectively, and optionally comprising the VH amino acid sequence of SEQ ID NO.:22 and the VL amino acid sequence of SEQ ID NO.:26, further optionally comprising a human IgG1 heavy chain comprising M428L and N434S mutations, and a human kappa light chain. Embodiment 95. The composition of Embodiment 93 or 94, further comprising an antibody or antigen-binding fragment comprising CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 amino acid sequences as set forth in SEQ ID NOs.:31-33 and 35-37, respectively, and optionally comprising the VH amino acid sequence of SEQ ID NO.:30 and the VL amino acid sequence of SEQ ID NO.:34, further optionally comprising a human IgG1 heavy chain comprising M428L and N434S mutations, and a human kappa light chain. Embodiment 96. A composition comprising the polynucleotide of any one of Embodiments 85-88 encapsulated in a carrier molecule, wherein the carrier molecule optionally comprises a lipid, a lipid-derived delivery vehicle, such as a liposome, a solid lipid nanoparticle, an oily suspension, a submicron lipid emulsion, a lipid microbubble, an inverse lipid micelle, a cochlear liposome, a lipid microtubule, a lipid microcylinder, lipid nanoparticle (LNP), or a nanoscale platform. Embodiment 97. A method of treating a sarbecovirus infection in a subject, the method comprising administering to the subject an effective amount of: (i) the antibody or antigen-binding fragment of any one of Embodiments 1-84; (ii) the polynucleotide of any one of Embodiments 85-88; (iii) the recombinant vector of Embodiment 89; (iv) the host cell of Embodiment 90; (v) the human B cell of Embodiment 91; and/or (vi) the composition of any one of Embodiments 92-96. Embodiment 98. The antibody or antigen-binding fragment of any one of Embodiments 1-84, the polynucleotide of any one of Embodiments 85-88, the recombinant vector of Embodiment 89, the host cell of Embodiment 90, the human B cell of Embodiment 91, and/or the composition of any one of Embodiments 92-96, for use in a method of treating a sarbecovirus infection in a subject. Embodiment 99. The antibody or antigen-binding fragment of any one of Embodiments 1-84, the polynucleotide of any one of Embodiments 85-88, the recombinant vector of Embodiment 89, the host cell of Embodiment 90, the human B cell of Embodiment 91, and/or the composition of any one of Embodiments 92-96, for use in the preparation of a medicament for the treatment of a SARS-CoV-2 infection in a subject. Embodiment 100. The method of Embodiment 97 or the antibody, antigen- binding fragment, polynucleotide, recombinant vector, host cell, human B cell, and/or composition for use of any one of Embodiments 98-99, wherein the method further comprises administering and/or wherein the subject has received an antibody or antigen-binding fragment comprising CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 amino acid sequences as set forth in SEQ ID NOs.:31-33 and 35-37, respectively, and optionally comprising the VH amino acid sequence of SEQ ID NO.:30 and the VL amino acid sequence of SEQ ID NO.:34, further optionally comprising a human IgG1 heavy chain comprising M428L and N434S mutations, and a human kappa light chain. Embodiment 101. The method of any one of Embodiments 97 and 100 or the antibody, antigen-binding fragment, polynucleotide, recombinant vector, host cell, human B cell, and/or composition for use of any one of Embodiments 98-99, wherein the method further comprises administering and/or wherein the subject has received an antibody or antigen-binding fragment comprising CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 amino acid sequences as set forth in SEQ ID NOs.:23-25 and 27- 29, respectively, and optionally comprising the VH amino acid sequence of SEQ ID NO.:22 and the VL amino acid sequence of SEQ ID NO.:26, further optionally comprising a human IgG1 heavy chain comprising M428L and N434S mutations, and a human kappa light chain. Embodiment 102. The method of any one of Embodiments 97, 100, and 101 or the antibody, antigen-binding fragment, polynucleotide, recombinant vector, host cell, human B cell, and/or composition for use of any one of Embodiments 98-99 and 101, wherein the sarbecovirus comprises a sarbecovirus of Clade 1a, a sarbecovirus of clade 1b, a sarbecovirus of clade 2, and/or a sarbecovirus of clade 3. Embodiment 103. The method of any one of Embodiments 97, 100, 101, and 102, or the antibody, antigen-binding fragment, polynucleotide, recombinant vector, host cell, human B cell, and/or composition for use of any one of Embodiments 97-102, wherein the sarbecovirus comprises a SARS-CoV-2. Embodiment 104. A method for in vitro diagnosis of a SARS-CoV-2 infection, the method comprising: (i) contacting a sample from a subject with an antibody or antigen-binding fragment of any one of Embodiments 1-84; and (ii) detecting a complex comprising an antigen and the antibody, or comprising an antigen and the antigen-binding fragment. Embodiment 105. The method of Embodiment 104, wherein the sample comprises blood isolated from the subject. Embodiment 106. An anti-SARS-CoV-2 antibody, or an antigen-binding fragment thereof, comprising: a VH comprising or consisting of the amino acid sequence QVQLVQSGAEVKKPGSSVKVSCKASGGIDNTYTISWVRQAPGQGLEWMG RIILMSGWANYAQTIQGRVTITADKSTSTAYMELTSLRSDDTAVYYCARGF HSDYYGWGDDDAFDFWGQGTLVTVSS (SEQ ID NO.:135); and a VL comprising or consisting of the amino acid sequence QTVLTQPPSVSGAPGQRVTISCTGSNSNIGAGYDVHWYQQLPGTAPKLLIV GNSNRPSGVPDRFSGSKSGTSASLAITGLQAEDEADYYCQSYDSSLSEPTWV FGGGTKLTVL (SEQ ID NO.:113). EXAMPLES EXAMPLE 1 ISOLATION AND TESTING OF ANTIBODY S2X259 A human monoclonal antibody, “S2X259”, was isolated from a patient who recovered from a SARS-CoV-2 infection. Tortorici, M.A., Czudnochowski, N., Starr, T.N. et al. Broad sarbecovirus neutralization by a human monoclonal antibody. Nature 597, 103–108 (2021). doi.org/10.1038/s41586-021-03817-4. S2X259 was expressed recombinantly and characterization studies were performed. S2X259 recognizes a highly conserved cryptic epitope of the receptor-binding domain and cross-reacts with spikes from all clades of sarbecovirus. S2X259 neutralizes spike- mediated cell entry of SARS-CoV-2, including variants of concern (B.1.1.7, B.1.351, P.1, and B.1.427/B.1.429), as well as a wide spectrum of human and potentially zoonotic sarbecoviruses through inhibition of angiotensin-converting enzyme 2 (ACE2) binding to the receptor-binding domain. Deep-mutational scanning and in vitro escape selection experiments demonstrate that S2X259 possesses an escape profile that is limited to a single substitution, G504D. Prophylactic and therapeutic administration of S2X259 protects Syrian hamsters (Mesocricetus auratus) against challenge with the prototypic SARS- CoV-2 and the B.1.351 variant of concern. EXAMPLE 2 ANTIBODY ENGINEERING AND TESTING OF ENGINEERED VARIANTS Sequence variants of S2X259 were generated that included one or more variable domain (also referred to as variable region) amino substitution mutations. S2X259-v5 (also referred to as “S2X259v5”) and S2X259-v7 (also referred to as “S2X259v7”) showed desirable characteristics and were selected for generation of further variant antibodies. The further variants included S2X259-543-v.1.1 (shown in certain Figures as “543”), S2X259-1-v1.1 (shown in certain Figures as “S2X259v7-1”), S2X259-189-v1.1 (shown in certain Figures as “S2X259v7-189”), S2X259-354-v1.1 (shown in certain Figures as “S2X259v5-354”), S2X259-69-v1.1 (shown in certain Figures as “S2X259v7-69”), S2X259-77-v1.1 (shown in certain Figures as “S2X259v7-77”), S2X259-221-v1.1 (shown in certain Figures as “S2X259v7-221”), and S2X259-269- v1.1 (shown in certain Figures as “S2X259v7-269”). These further variants were tested in binding and in vitro neutralization assays. Antibodies were expressed as recombinant IgG1m17,1, containing M428L and N434S mutations in the Fc. In some experiments, a respective parental antibody/antibodies (S2X259-v5, S2X259-v7) was included for comparison. In some experiments, antibodies S2E12 (Tortorici et al., Science 370:6419 (990-957) (2020) DOI: 10.1126/science.abe3354) and VIR-7831 (VH of SEQ ID NO.:30, VL of SEQ ID NO.:34, IgG1 with M428L and N434S mutations in Fc, also known as sotrovimab) were included as comparators. In the experiments shown in Figures 3A-4E and 6A-6D, capture solutions containing the further variant antibodies are identified as ELN31024-…, with the numbers following the ellipsis corresponding to the above naming (e.g., ELN31024-354 contains S2X259- 354-v1.1). Data from the experiments are shown in the Figures. As shown in Figures 1A- 1D, the further variants have similar or even improved neutralization (VSV-PVS system) against SARS-CoV-2 (Wuhan-Hu-1) and SARS-CoV as compared to the parental antibodies. Unlike the parental antibodies, the further variant antibodies effectively neutralize SARS-CoV-2 variant comprising a G504D mutation. The further variant antibodies also neutralize SARS-CoV-2 variant B.1.617.2 (Figures 2A-2D). As shown in Figures 3A-3K, certain further variant antibodies bind to sarbecoviruses from clades 1a, 1b, 2, and 3. As shown in Figures 4A-4C, certain further variant antibodies neutralize infection by SARS-CoV-2, SARS-CoV, SARS-CoV-2 delta variant, and SARS-CoV-2 G504D variant. As shown in Figures 4D-4E, certain further variant antibodies bind to sarbecoviruses from clades 1a, 1b, 2, and 3, some with increased affinity (BLI, apparent KD) as compared to S2X259-v5. As shown in Figure 5, the tested further variant antibodies did not demonstrate polyreactivity. Additional characteristics of the further variant antibodies (derived from yeast cells, instead of from mammalian cells as in Figures 1A-5) are shown in Figures 6A- 6D, and include binding kinetics, purification, stability, and neutralization. S2X259.543-v1.1, S2X259-1-v1.1, and S2X259-69-v1.1 had favorable characteristics based on, e.g., binding (SARS-CoV-2 Wuhan-Hu-1, SARS-CoV-2 G504D (single escape), and PG-GX (G504N)) by FACS and neutralization against SARS-CoV-2 Wuhan-Hu-1, SARS-CoV-2 G540D, and SARS-CoV. S2X259.543-v1.1, for example, had improved binding affinity and neturalization properties as compared to S2X259-v5. From these, additional variant antibodies (including S2X259.1-v3.2, S2X259.543-v4.4 (also referred-to as S2X259-v50), S2X259.1-v2.1, S2X259.69-v2.3, S2X259.1-v8.2, S2X259.543-v8.4, S2X259.543-v8.6) were generated, as summarized in Table 2. These antibodies contained mutations to potentially imnprove developability. Antibodies were expressed as recombinant IgG1 g1m,17, 1 with M428L and N434S mutations in CH3. For example, S2X259.543-v4.4 had improved neutralization potency against SARS-CoV-2 (Wuhan-Hu-1 wild-type and with G504D) VSV pseudoviruses as compared to S2X259.543-v1.1 (data not shown), with a significant improvement in neutralizing SARS-CoV-2 G504D as compared to S2X259.543-v1.1. S2X259.543-v4.4 binds a breadth of RBDs from different clades, including Anlong-112, ZC45, and SARS-CoV-2 G504D (to which S2X259-v5 did not detectably bind in the assay), and had improved binding to, for example, SX2011, YN2013, and SC2018, as compared to S2X259-v5. From these sequence variant antibodies, S2X259.543-v4.4 (also referred-to as S2X259-v50), having the VH amino acid sequence of SEQ ID NO.:109 and the VL amino acid sequence of SEQ ID NO.:113, was selected as a basis for generating further variant antibodies with one or more mutations in the V-regions, and these variant antibodies were interrogated for potential improvements in binding affinity, breadth, and neutralization. EXAMPLE 3 NEUTRALIZATION AND BINDING BY S2X259-V50 AND VARIANT ANTIBODIES In vitro neutralization assays were conducted with S2X259-v50 and variant antibodies on an extended SARS-CoV panel (i.e., Wuhan-Hu, BA.2, BA 4.6, BA.5 and SARS-CoV). VSV pseudotype system was used, with Vero E6 as target cells. VSV pseudovirus/antibody was incubated for 1 hour. Antibodies were used at an equal final dilution of 1/10. Absolute IgG concentrations were adjusted during data analysis, after BLI-based quantification. Virus was diluted to reach MOI of 0.1. Vero E6 cells were infected with the virus/Ab mix for 1 hour. Luminescence-based readout was conducted after 24 hours. Neutralization potency is inversely proportional to the luminescence (lum) signal. Percentages of neutralization are calculated referencing to lummax/lummincontrols. Dose-response curves are plotted in Prism and IC50 interpolated. Figure 7 shows Octet quantification of purified antibodies, showing fluctuation in quantification values between 692 and 162 ug/m. A first screening step was performed; Figure 8 shows neutralization IC50 values and a plot of IC50 _parental /IC50 _variant for S2X259-v50 variant antibodies (n=35) versus SARS-CoV-2 BA.5. A gain in potency up to 4-fold was observed compared to the parental antibody, S2X259-v50. Twenty-six variants were selected for a second screening step based on fold-change of BA.5 versus Wuhan-Hu-1 for each variant antibody. Figure 9 shows neutralizing activity of S2X259-v50 variants vs. a panel of SARS-CoV-2 and SARS-CoV-1 pseudoviruses in a second screening step (n= 26). S2X259.774 (VH amino acid sequence of SEQ ID NO.:135, VL amino acid sequence of SEQ ID NO.:113) was identified as having ~5-fold neutralization improvement on BA.5 and BA4.6, and improvement on BA.5 G504D. S2X259.774 is also referred to as S2X259-774. Figure 10 shows neutralization curves for S2X259-v50 and S2X259-774 vs. a panel of SARS-CoV-2 pseudoviruses. Figure 11 shows neutralization IC50 values for S2X259-v50 and variant antibodies. S2X259-v50 loses neutralization capacity vs D504G when this substitution mutation is grafted in the BA.5 backbone. Neutralization of BA.5 D504G is acquired by some of the S2X259-v50 variants shown in the figure. S2X259-774 was selected for recombinant expression in mammalian cells. Figure 12 shows correlation of neutralizing potency across different SARS- CoV-2 strains. Figure 13 shows a summary of neutralization data for S2X259-v50 variant antibodies, sorted based on BA.5 IC50 values. S2X259-774 was selected for recombinant expression in mammalian cells. Figure 14A shows neutralization IC50 values for the indicated antibodies against a panel of SARS-CoV-2 strains and SARS-CoV-1. Figure 14B summarizes fold-change in IC50 values for S2X259-v50 variants vs. the parental antibody, across SARS-CoV-2 strains. Figure 15 shows binding and neutralization correlation plots for S2X259-v50 and variant antibodies across SARS-CoV-2 strains and SARS-CoV-1. S2X259-774 is the bottom-left-most dot in the plots for Wuhan-Hu, BA.2, BA.5, BA.4.5, and G504D. EXAMPLE 4 SURFACE PLASMON RESONANCE (SPR) ASSAYS MEASURING BINDING An SPR experiment was conducted using the following settings. Surface: anti- human Fc capture (Cytiva); Ligands: Yeast-produced variant antibodies expressed as recombinant IgG (S2X259v50 variants, 5 control IgGs: S309, S2X259-v50, S2K146, S2X324 (see e.g. Cameroni et al., Nature 602:664-670 (2022); Park et al. BioRxiv doi:10.1101/2022/.05.08.491108; PMID 35677069), neg. control); Analytes: His-Avi- tagged RBDs: BA.2 and BA.4/5; Analyte concentration series: 4-fold dilution series, 3 concentrations (50, 12.5, 3.125nM); Single-cycle kinetics. Thirteen S2X259-v50 variants were evaluated for binding to a panel of RBDs using SPR. Each variant antibody selected for the SPR experiment had to be in the top five neutralizers against each CoV strain. Figure 16 shows (left) the SARS-CoV RBD panel, and the top neutralizing antibodies against each strain. Figure 17 shows the SPR experimental setup. In a quality control check, the chip surface was completely regenerated. The negative control antibody “D12” (anti-RSV) did not bind any of the tested receptor- binding domains (RBDs). Figure 18 shows binding data for D12 against BA.4/5 and BA.4.6. Previous data was biased towards lower KD values due to incomplete rengeration carrying through additional antibody on the surface. Figure 19 correlation of neutralization (IC50) versus binding (KD for RBD, as measured by SPR) results for S2X259-v50 variant antibodies against the indicated CoVs (G504D excluded). Figure 20 shows fold-change improvement in neutralization and binding for certain S2X259-v50 variant antibodies against the S2X259-v50 parental antibody. Figure 21 shows neutralization and binding results of certain S2X259-v50 variant antibodies against SARS-CoV-2 Wuhan Hu-G504D. Second dot from left in top line = parental antibody S2X259-v50; bottom-left dot = S2X259-v774. Figure 22 shows that the S2X259 antibody binds across coronavirus clades. Binding affinity of S2X259-v50 and variants thereof to ZC45 and BGR08 is shown in Figure 23. Figure 24 shows (left) S2X259-v50 binding affinity (KD) correlations between CoV strains and (right) affinity correlations for (top) BGR08 or ZC45 versus SARS- CoV1 and (bottom) BA.46 versus BA.4 or BA.5 by S2X259-v50 variant antibodies. Figure 25 shows example sensorgrams for S2X259-v50 (left) and S2X259.774 (right, shown as “E09”). Figure 26 shows a summary of binding affinity (KD) for S2X259-v50 and certain variant antibodies against the indicated CoVs, and Figure 27 summarizes fold- improvement in binding affinity for the variant antibodies, with reference to parental S2X259-v50. The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, including U.S. Provisional Patent Application No.63/385,748, filed on December 1, 2022, are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments. These and other changes can be made to the embodiments in light of the above- detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.