Changes in CD8 Cell Subpopulations Induced by Antiretroviral Therapy in Human Immunodeficiency Virus Infected Patients

Although CD4⁺ T cells are the main target of HIV infection, CD8⁺ cells also play important roles in the interaction between HIV and the host immune system. The aim of this study was to analyze the effect of anti-HIV therapy on the relative proportion of some important CD8⁺ cell subpopulations. Five HIV-infected patients were enrolled, and blood samples were collected several times, within 90 days from the initiation of therapy. CD4⁺ cell count and HIV viremia were investigated, as well as the expression of CD38, HLA-DR, CD28, CD57, CD30, CD95 molecules on CD8⁺ cells. A complex remodeling of CD8⁺ cell subpopulations took place between week 2 and week 7 of treatment. This remodeling mainly consisted of: i) decrease of CD8⁺CD38⁺ and CD8⁺DR⁺ cells; ii) increase of CD8⁺CD28⁺ cells; and iii) decreased expression of the CD95/Fas molecule on CD8⁺ cells. Overall, these findings suggest that effective anti-HIV therapy induces changes of CD8⁺ subpopulations showing the reversal of the state of chronic activation that is caused by viral replication.