IL-2 is majorly produced by CD4+ and CD8+ T cells, as well as some B cells and dendritic cells; its important function is to foster the proliferation of CD4+ and CD8+ T cells [38] Few recent studies have reported that higher levels of IL-2 was seen in asymptomatic and mild COVID-19 groups [5,39]. The gene discussed is CD8A; the disease is COVID-19.