Generation and characterization of SARS-CoV-2 neutralizing antibodies associated with clinical outcome

Pratik Das Michal Werbner ¹ Modi Safra ^2,3 Pazit Polak ^2,3 Moshe Matan ⁴ Avi Peretz ⁴ Moshe Dessau ⁵ Gur Yaari ^2,3 Meital Gal-Tanamy ¹

¹Molecular Virology Laboratory, The Azrieli Faculty of Medicine, Bar Ilan University, Israel
²Bio-engineering, Faculty of Engineering, Bar Ilan University, Israel
³Institute of Nanotechnologies and Advanced Materials, Bar Ilan University, Israel
⁴Clinical Microbiology Laboratory, Baruch Padeh Medical Center, Israel
⁵The Laboratory of Structural Biology of Infectious Diseases, The Azrieli Faculty of Medicine, Bar Ilan University, Israel

Aim and Background: The ‘novel coronavirus disease’ (2019-nCoV) or severe acute respiratory syndrome (SARS-CoV-2) is the leading cause of the recent global catastrophe known as the COVID-19 disease which originated in December 2019. SARS-CoV-2 enters the host cells via interaction between the angiotensin-converting enzyme 2 (ACE2) receptor and the viral envelop protein ‘spike’. Emerging SARS-CoV-2 variants contain mutations that resist antibody neutralization. The use of neutralizing antibodies is currently the most promising approach to prevent the viral infection.
Here, we propose to generate an effective SARS-CoV-2 neutralizing antibodies associated with specific clinical outcome, and investigate their neutralizing abilities, epitopes, resistance and neutralization breath.

Methods: For identifying neutralizing antibody clones against SARS-CoV-2, a dataset containing immunoglobulin heavy and light chain sequences from 13 severe COVID-19 patients and 50 mild/moderate patients were collected. By antibody repertoire analysis, we identified several neutralizing antibody clones prevalent in COVID-19 patients. The full-length antibodies were prepared by cloning the respective heavy and light chain sequences for expression and purification. Neutralization assays were conducted to evaluate the neutralization capacity against VSV and lentiviral based SARS-CoV-2 pseudo-particles. For epitope mapping and selection of resistant mutations, replication competent rVSV expressing SARS-CoV-2-S was prepared.

Results and Conclusion: We identified antibody clones that are prevalent in COVID-19 patients and produced the full-length antibodies successfully. We demonstrated that these antibodies efficiently neutralize SARS-CoV-2. This study is expected to lead towards generation of antibodies with various mechanisms of neutralization that may be efficient as a combination therapy for the cure of COVID-19 patients.