COVID-19 vaccines by Oxford, CanSino and Pfizer all trigger immune responses
More coronavirus vaccine candidates have passed initial safety tests and induce immune responses that might protect against the virus. All volunteers in a small clinical trial who were given an experimental vaccine developed by researchers at the University of Oxford made antibodies against a protein the virus uses to break into cells. Those participants also produced immune cells called T cells that are important for long-lived immunity, the researchers, working with the global pharmaceutical company AstraZeneca, report July 20 in the Lancet. Levels of neutralizing antibodies, which can block viral entry into cells, were at levels on par with those from people who have recovered from COVID-19. No serious side effects were seen, particularly when volunteers took acetaminophen after getting an injection. “The results so far are encouraging,” says Mark Poznansky, a vaccinologist who directs the Vaccine & Immunotherapy Center at Massachusetts General Hospital in Boston who was not involved in the study....