Researchers from Scripps Research, International AIDS Vaccine Initiative (IAVI), and University of California San Diego School of Medicine discovered antibodies in the blood of patients who recovered from COVID-19 that provide powerful protection against SARS-CoV-2, , the coronavirus that causes the disease, when tested in animals and human cell cultures. The research sets the stage for clinical trials and additional tests of the antibodies, which are now being produced as potential treatments and preventives for COVID-19.
Dr. Thomas Rogers, adjunct assistant professor in the Department of Immunology & Microbiology at Scripps Research, and assistant professor of Medicine at UC San Diego and his colleagues took blood samples from patients who had recovered from mild-to-severe COVID-19. In parallel, scientists at Scripps Research and IAVI developed test cells that express ACE2, the receptor that SARS-CoV-2 uses to get into human cells. In the initial experiments, the team tested whether antibody-containing blood from the patients could bind to the virus and strongly block it from infecting the test cells.
In less than seven weeks, the scientists were able to isolate more than 1,000 distinct antibody-producing immune cells, called B cells, each producing a distinct anti-SARS-CoV-2 antibody. The team then obtained the antibody gene sequences from these B cells so that they could produce the antibodies in the laboratory. The team screened these antibodies individually and identified several that, even in tiny quantities, could block the virus in test cells, and one that could also protect hamsters against heavy viral exposure. In their attempts to isolate anti-SARS-CoV-2 antibodies from the COVID-19 patients, the researchers also found one that can also neutralize SARS-CoV, the related coronavirus that caused the 2002-2004 outbreak of severe acute respiratory syndrome (SARS) in Asia.