Lee and colleagues observed that CD4 memory T cells that express HLA-DR were detectable in the stage of acute HIV infection [19]; the average expression levels of CCR5, PD-1, and Tim-3 were higher in the HLA-DR+ T cell subset, whereas the average Lag-3 expression was higher in their HLA-DR− counterparts [19]. This evidence concerns the gene PDCD1 and HIV infectious disease.