Potent neutralization of SARS-CoV-2 in vitro and in an animal model by a human monoclonal antibody
clinical diagnostics immunology/immunity therapeutics
Authors: Wei Li et al.
Link to paper: https://www.biorxiv.org/content/10.1101/2020.05.13.093088v1
Journal/ Pre-Print: pre-print, posted on bioRxiv on 14th May 2020
Tags: Immunology/Immunity, Clinical/ Diagnostics, Therapeutics
Research Highlights
1. Fully human monoclonal IgG1 Ab against spike RBD generated using phage display can neutralize SARS-Cov2 in vitro and protect from viral challenge in a mouse model of infection.
Summary
In this study authors describe generation of human monoclonal IgG1 antibody neutralizing SARS-Cov2. The Ab was selected by phage display from a large human naïve library using the receptor binding domain (RBD) of the SARS-CoV-2 spike protein as bait. Selected Ab can block binding of RBD to ACE2 receptor and neutralize the virus in vitro. Administration of the Ab to hACE2 transgenic mice prior to challenge with SARS-Cov2 produces a protective effect. The authors describe relatively few somatic mutations and speculate this could allow rapid elicitation of a response.
Impact for SARS-CoV2/COVID19 research efforts
Develop a vaccine for SARS-CoV2/COVID19
Inhibit SARS-CoV2/COVID19 transmission
Treat SARS-CoV2/COVID19 positive individuals
Study Type
· In vitro study
· In vivo study (hACE2 transgenic mouse model)
Strengths and limitations of the paper
Novelty: Rapid selection of human antibodies from a large library allows rapid pandemic responsiveness
Neutralizing monoclonal SARS-Cov-2 RBD-specific Abs have been reported a number of times already.
Standing in the field: Not controversial.
Appropriate statistics: Yes.
Viral model used: SARS-CoV-2 and SARS-CoV as control
Full-length viruses expressing luciferase (SARS-CoV-2-SeattlenLuc and SARS-CoV-UrbaninLuc) used in one of the two neutralization assays performed
Translatability: There is potential for translation into clinical application.
Main limitations: Neutralization data presented in a somewhat confusing way
Only n = 5 in the in vivo experiment with no protective effect in 1 of the animals, however result still statistically significant.