T cells are among the immune system’s most powerful weapons, but their importance for battling SARS-CoV-2, the virus that causes COVID-19, has been unclear. Now, two studies show infected people harbor T cells that target the virus — and may help them recover. Both studies also found that some people never infected with SARS-CoV-2 have these cellular defenses, most likely because they were previously infected with other coronaviruses that cause the common cold. “This is encouraging data,” says virologist Angela Rasmussen of Columbia University, who wasn’t involved in the work. Although the studies don’t clarify whether people who clear a SARS-CoV-2 infection can ward off the virus in the future, both identified strong T cell responses to it, which “bodes well for the development of long-term protective immunity,” Rasmussen says. The findings could also help researchers create better vaccines.
Source: T cells found in coronavirus patients ‘bode well’ for long-term immunity