Experimental COVID-19 vaccine prevents severe disease in mice
An experimental vaccine is effective at preventing pneumonia in mice infected with the COVID-19 virus, according to a study from Washington University School of Medicine in St. Louis. The vaccine, which is made from a mild virus genetically modified to carry a key gene from the COVID-19 virus, is described in the journal Cell Host and Microbe.
"Unlike many of the other vaccines under development, this vaccine is made from a virus that is capable of spreading in a limited fashion inside the human body, which means it is likely to generate a strong immune response," said co-senior author Michael S. Diamond, MD, PhD, the Herbert S. Gasser Professor of Medicine and a professor of molecular microbiology, and of pathology and immunology. "Since the virus is capable of replicating, it can be grown to high levels in the lab, so it's easy to scale up and should be more cost-effective than some of the other vaccine candidates. So while what we have shown is just the proof of concept, I think it's very promising. Our vaccine candidate is now being tested in additional animal models with the goal of getting it into clinical trials as soon as possible."
Diamond and colleagues -- including co-senior author Sean Whelan, PhD, the Marvin A. Brennecke Distinguished Professor and head of the Department of Molecular Microbiology; and co-first authors Brett Case, PhD, a postdoctoral researcher in Diamond's laboratory, and Paul W. Rothlauf, a graduate student in Whelan's laboratory -- created the experimental vaccine by genetically modifying vesicular stomatitis virus (VSV), a virus of livestock that causes only a mild, short-lived illness in people. They swapped out one gene from VSV for the gene for spike from SARS-CoV-2, the virus that causes COVID-19. The hybrid virus is called VSV-SARS-CoV-2.