Xavier lab reveals how the body fights Covid-19

CMIT Co-Director Ramnik Xavier is one of many CMIT investigators leveraging their expertise and resources to study SARS-CoV-2, the virus that causes Covid-19.

Pairing their expertise in immunology with that of computational and structural biologists, members of the Xavier lab reveal the reason why immune responses to Covid-19 vary so widely between individuals.

By characterizing the immune cells and antibodies that successfully fought off Covid-19 in patients, researchers have created a blueprint for a successful defense against SARS-CoV-2. This blueprint could help scientists better understand why some people don’t respond as well to existing Covid-19 vaccines or therapies, a first step toward improving vaccines and treatments for SARS-CoV-2 and other viruses like it.

See below for a preview of the piece by Sarah C.P. Williams for Broad News and Media

How B cells fight the COVID-19 virus

A study of antibody-producing B cells from patients who recovered from COVID-19 reveals a new cross-reactive antibody and what makes some B cells more effective at neutralizing the virus.

Inside the body of a person with COVID-19, the immune system’s B cells are engaged in a full-scale battle with the SARS-CoV-2 virus. But some B cells are better at this than others. Now, scientists from the Broad Institute of MIT and Harvard, Massachusetts General Hospital, California Institute of Technology, Brigham and Women’s Hospital, and other institutions have for the first time described key characteristics of B cells that are effective at neutralizing, or inactivating, the SARS-CoV-2 virus and related coronaviruses.

The team studied blood samples from 14 people who recovered from COVID-19, and revealed distinct patterns of gene expression in B cells that produce antibodies that bind tightly to and neutralize SARS-CoV-2. They also discovered a new antibody, BG10-19, which neutralizes the virus, variants of concern such as ones first identified in the UK and South Africa, and the coronavirus that caused the 2003 SARS outbreak.

The findings, published today in Cell, could help scientists better understand why some people don’t respond as well to existing COVID-19 vaccines or therapies, a first step toward improving vaccines and treatments.

“By studying COVID-19 patients who recovered from the virus, we learned a lot about the body’s defense mechanisms. We found that not all B cells are the same, and that some are super antibody-producers. The findings offer insight into how to design antibodies that can neutralize several coronaviruses,” said Ramnik Xavier, co-senior author of the study …