PDCD1 and HIV infectious disease: To summarize, PD-1 is the factor that is frequently reported across three periods alongside HIV infections, whereas Ki-67 [19, 28] and IP-10 [9, 34] are frequently reported in pretreatment HIV-infected individuals, and HLA-DR [18, 19, 35, 37, 42] and CD38+HLADR+CD8 T cells [18, 35, 42] are frequently reported in patients subjected to a long period of ART.