To date, multiple studies have shown that COVID-19 vaccination elicits a stable and fully functional CD4+ and CD8+ T cell response that is maintained across different vaccine platforms (e.g. mRNA-1237, BNT162b2m Ad26.CoV2.S and NVX-CoV2373) and VOCs (14, 15, 18–26). This evidence concerns the gene CD8A and COVID-19.