Rapid isolation and profiling of a diverse panel of human monoclonal antibodies targeting the SARS-CoV-2 spike protein

Abstract

Antibodies are a principal determinant of immunity for most RNA viruses and have 54 promise to reduce infection or disease during major epidemics. The novel 55 coronavirus SARS-CoV-2 has caused a global pandemic with millions of infections 56 and hundreds of thousands of deaths to date 1,2 . In response, we used a rapid 57 antibody discovery platform to isolate hundreds of human monoclonal antibodies 58 (mAbs) against the SARS-CoV-2 spike (S) protein. We stratify these mAbs into five 59 major classes based on their reactivity to subdomains of S protein as well as their 60 cross-reactivity to SARS-CoV. Many of these mAbs inhibit infection of authentic 61 SARS-CoV-2 virus, with most neutralizing mAbs recognizing the receptor-binding 62 domain (RBD) of S. This work defines sites of vulnerability on SARS-CoV-2 S and 63 demonstrates the speed and robustness of new antibody discovery methodologies. 64 65 Human mAbs to the viral surface spike (S) glycoprotein mediate immunity to other 66 betacoronaviruses including SARS-CoV 3-7 and Middle East respiratory syndrome 67 (MERS) 8-17 . Because of this, we and others have hypothesized that human mAbs may 68 have promise for use in prophylaxis, post-exposure prophylaxis, or treatment of SARS-69 CoV-2 infection 18 . MAbs can neutralize betacoronaviruses by several mechanisms 70 including blocking of attachment of the S protein RBD to a receptor on host cells (which 71 for SARS-CoV and SARS-CoV-2 1 is angiotensin-converting enzyme 2 [ACE2]) 12 . We 72 hypothesized that the SARS-CoV-2 S protein would induce diverse human neutralizing 73 antibodies following natural infection. While antibody discovery usually takes months 74 to years, there is an urgent need to both characterize the human immune response to 75 SARS-CoV-2 infection and to develop potential medical countermeasures. Using Zika 76 virus as a simulated pandemic pathogen and leveraging recent technological advances 77in synthetic genomics and single-cell sequencing, we recently isolated hundreds of 78 was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission.

A rapid and efficient screening system for neutralizing antibodies and its application for the discovery of potent neutralizing antibodies to SARS-CoV-2 S-RBD

“…The optimization of the screening platform). First, we collected the blood samples from convalescent patients with COVID- 19. These patients were the earliest confirmed cases of SARS-CoV-2 infection in Chongqing City, over half of the patients who had a history of close contact with the earliest infectors.…”

“…Its viral spike(S) containing the receptorbinding domain (RBD) is responsible for binding to the receptor angiotensin-converting enzyme-2(ACE2) receptor on the host cells 8,9 . To date, several teams have promptly developed some potent neutralizing mAbs to SARS-CoV-2 [10][11][12][13][14][15][16][17][18][19][20][21][22] . In these studies, different methodologies were employed for screening of neutralizing Abs.…”

“…Some studies utilized SARS-CoV-2 S -or RBD-labeled memory B cells from convalescent patients with SASR-CoV-2 infection and directly amplified Ab genes by RT-PCR and nested PCR at a single-cell level 10,18 . In other studies, plasma cells were activated and expanded with stimulators and cytokines in vitro for selecting neutralizing Abs 14,19 . Humanized mice were also used to generate full human monoclonal antibodies against S protein 11,22 .…”

Controlling the SARS-CoV-2 Spike Glycoprotein Conformation

“…From the perspective of immunogen development, the constructs developed here present an opportunity to examine the ability of differentially stabilized S-protein particles to induce two different, yet important antibody responses. First, the disulfide-linked 'down' state locked double mutant (rS2d) would presumably eliminate receptor binding site targeting antibodies which make up the majority of observed responses 30,31 . Indeed, a study of MERS responses suggests non-RBD responses (particularly NTD and S2 epitopes) will play an important role in vaccine induced protection 32 .…”

Structures of human antibodies bound to SARS-CoV-2 spike reveal common epitopes and recurrent features of antibodies

“…were over-represented . Other studies have also reported anti-SARS-CoV-2 mAbs derived from these genes (Brouwer et al, 2020;Cao et al, 2020;Chi et al, 2020;Ju et al, 2020;Rogers et al, 2020;Seydoux et al, 2020;Wu et al, 2020c;Zost et al, 2020).…”