(105) evaluated the frequency of different T cell populations, CD8, CD4, γδ (Vδ1 and Vδ2), and mucosal-associated invariant T (MAIT) cells in the acute phase of the infection in COVID-19 patients showing a decrease in cytolytic populations CD8, MAIT and Vδ2 T cells. The gene discussed is CD4; the disease is COVID-19.