CD4 and HIV infectious disease: These phenotypic findings have been associated with the lack of control of the immune system on viral replication, owing to the fact that, in HIV infection, CD45RA−CCR7− CD4+ T cells are functionally characterized by low-IL-2/high interferon(IFN)-γ production and minimal proliferative ability, and CD45RA−CCR7− CD8+ T cells are endowed with lower content of lysis molecules, low proliferative ability, and altered cytokine production and ability [20]–[26].