Although the immune profiles of T cells from convalescent COVID-19 patients were different from those of T cells from age-matched unexposed elderly patients, it was surprising that the expression of surface markers, including CD4, CD8, CD25, PD-1 and TRAIL, was similar between convalescent COVID-19 patients and unexposed younger patients (Fig. 1G). The gene discussed is CD8A; the disease is COVID-19.