Early in hantavirus infection, a greater increase in CD8+ T cells than CD4+ T cells was observed, and, in the acute phase of the infection, CD8+ T cells have been found to express Ki67 (marker of cell proliferation), CD38 (required for calcium signaling to trigger granule release), and HLA-DR (T cell receptor) [35]. The gene discussed is CD8A; the disease is hantavirus infectious disease.