TY - JOUR T1 - Unbiased interrogation of memory B cells from convalescent COVID-19 patients reveals a broad antiviral humoral response targeting SARS-CoV-2 antigens beyond the spike protein JF - bioRxiv DO - 10.1101/2021.01.27.428534 SP - 2021.01.27.428534 AU - Jillian M. DiMuzio AU - Baron C. Heimbach AU - Raymond J. Howanski AU - John P. Dowling AU - Nirja B. Patel AU - Noeleya Henriquez AU - Chris Nicolescu AU - Mitchell Nath AU - Antonio Polley AU - Jamie L. Bingaman AU - Todd Smith AU - Benjamin C. Harman AU - Matthew K. Robinson AU - Michael J. Morin AU - Pavel A. Nikitin Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/01/28/2021.01.27.428534.abstract N2 - 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.Competing Interest StatementThe authors have declared no competing interest. ER -