T cells can attack many coronavirus targets, even on new variants

Editor's Note

This study by researchers at La Jolla Institute for Immunology, La Jolla, California, finds that T cells fight SARS-CoV-2 by targeting a broad range of sites on the virus, beyond the key sites on the spike protein. By attacking the virus from many angles, the T cells can potentially recognize different SARS-Cov-2 variants.

The researchers examined T cells from 100 patients who had recovered from COVID-19. They found that not all parts of the virus induce the same strong immune response in everyone. T cells can recognize dozens of epitopes (the part of an antigen or foreign protein that stimulates an immune response) on the SARS-Cov-2 virus, and these immunodominant sites change from person to person.

On average, each patient’s immune system had the ability to recognize about 17 CD8+ T cell (helper T cells) epitopes and 19 CD4+ T cell (killer T cells) epitopes.

Among the many epitopes the researchers uncovered, they found several additional epitopes on the spike protein. This means the immune system would still be able to fight infection, even if the virus mutates, the researchers say.