Generation of memory B cells secreting anti-SARS-CoV-2 neutralizing antibodies from human subjects recently recovered from COVID- 19 infection for future large-scale antibody production

Abstract

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and the consequent COVID-19 pandemic in 2020 underscored the need for rapid development of treatments and protective measures against the eruption of infectious diseases. An important strategy in these is to target and disrupt viral and host interactions by administering monoclonal antibodies. The SARS-CoV-2 infection is mediated by the binding of the viral spike protein with the host cell’s angiotensin-converting enzyme 2 (ACE-2) receptor. Notably, this interaction can be blocked using monoclonal antibodies that specifically recognize the viral spike S1 subunit or its receptor binding domain (RBD), thereby preventing infection. High-affinity antibodies are normally generated by B cells as a result of the adaptive immune response to infections or vaccinations. Particularly, memory B cells are a valuable resource of anti-viral antibodies. My objective is to isolate and clone memory B cells from healthy donors who were both vaccinated and recovered from SARS-CoV-2 with an aim to produce in vitro specific anti-SARS-CoV-2 monoclonal antibodies for the prevention and treatment of SARS-CoV-2 infections. Here, I screen five donors for their humoral immune response against SAS-CoV-2 using an automated western blot and a specific virus neutralization assay. Then, I describe and optimize two strategies to generate neutralizing antibodies against SARS-CoV-2 from the donors’ memory B cell repertoire. These strategies include generating memory B cell cultures at various cell densities and establishing a lymphoblastoid cell line. The lymphoblastoid cell lines are further validated by the screening of antibodies against SARS-CoV-2 in the culture media. This project moves towards large-scale generation of broadly neutralizing SARS-COV-2 antibodies that can overcome viral escape through mutations and variations. Furthermore, I describe and optimize two strategies that can later be used for any viral infectious disease.

Date of Award	2025
Original language	American English
Awarding Institution	HBKU College of Health & Life Sciences