WashU Immunologist & Virologist is Testing Vaccines against the Delta Variant in Animal Models

    By Kathleen Berger, Executive Producer for Science and Technology

    During the pandemic winter months, virologist and immunologist Michael Diamond, MD, PhD and his colleagues at Washington University School of Medicine in St. Louis conducted laboratory experiments to understand variants of COVID-19. The researchers found that the variants can evade antibodies that work against the original form of the virus that causes COVID-19.

    The research team determined variants potentially undermine the effectiveness of COVID-19 vaccines and found more antibody is needed to neutralize the new variants.

    “We had serum from humans that were vaccinated and then tested against the variant viruses.” said Diamond.

    Now the professor of molecular microbiology, and of pathology and immunology has continued to advance the research in his lab using animal models. Diamond is now focusing on the highly contagious Delta variant.

    “This is a much more highly transmissible virus than the original virus,” Diamond explained. “And so basically people who are not vaccinated now are at high risk for getting delta virus infection. When new variants emerged, we then acquire them, evaluate them and then test them in that process, both in cell culture based systems, but then also in vivo, in the context of how vaccines perform and how antibodies perform.”

    As mutations are identified, intense study by Diamond and his colleagues through the testing of vaccines against the variants in animal models will help the larger scientific community determine the best approach for vaccines moving forward.

    “As we get more and more variants as they change and accumulate these mutations, there’s concern that we’re going to have to make some substitution at some point, either by boosting with vaccines that are different or boosting the vaccines that are the same,” he explained.

    The science in Diamond’s lab is part of a large-scale effort to make decisions about vaccinations and vaccine booster shots.

    “We have programs with the NIH (National Institutes of Health), a large collaboration with my group, many other groups, as a network to test all of the approved vaccines or close to approved vaccines against historical vaccines, as well as variant-based vaccines that the manufacturers are generating. So collectively doing that with all of the variant viruses, the key variants.”