Abstract
Patients who recover from SARS-CoV-2 infections produce antibodies and antigen-specific T cells against multiple viral proteins. Here, an unbiased interrogation of the anti-viral memory B cell repertoire of convalescent patients has been performed by generating large, stable hybridoma libraries and screening thousands of monoclonal antibodies to identify specific, high-affinity immunoglobulins (Igs) directed at distinct viral components. As expected, a significant number of antibodies were directed at the Spike (S) protein, a majority of which recognized the full-length protein. These full-length Spike specific antibodies included a group of somatically hypermutated IgMs. Further, all but one of the six COVID-19 convalescent patients produced class-switched antibodies to a soluble form of the receptor-binding domain (RBD) of S protein. Functional properties of anti-Spike antibodies were confirmed in a pseudovirus neutralization assay. Importantly, more than half of all of the antibodies generated were directed at non-S viral proteins, including structural nucleocapsid (N) and membrane (M) proteins, as well as auxiliary open reading frame-encoded (ORF) proteins. The antibodies were generally characterized as having variable levels of somatic hypermutations (SHM) in all Ig classes and sub-types, and a diversity of VL and VH gene usage. These findings demonstrated that an unbiased, function-based approach towards interrogating the COVID-19 patient memory B cell response may have distinct advantages relative to genomics-based approaches when identifying highly effective anti-viral antibodies directed at SARS-CoV-2.
【저자키워드】 COVID-19, convalescent plasma, Antibody Response, B cell repertoire, 【초록키워드】 SARS-CoV-2, S protein, spike, antibody, SARS-COV-2 infection, monoclonal antibody, Viral proteins, Proteins, Anti-viral, Protein, Immunoglobulin, nucleocapsid, RBD, membrane, Somatic hypermutation, convalescent patient, Pseudovirus neutralization assay, COVID-19 patient, antigen-specific T cell, components, anti-viral antibody, full-length, approach, effective, Cell, memory B, full-length protein, produced, identify, performed, specific antibody, characterized, ORF, majority, demonstrated, the receptor-binding domain, expected, the Spike, auxiliary, COVID-19 convalescent patient, the antibody, 【제목키워드】 Antiviral, SARS-CoV-2 antigen, memory B cell, humoral, the spike protein, reveal, convalescent COVID-19 patient,