CD4 and AIDS: HAART was found to clearly improve the quality of life of acquired immune deficiency syndrome (AIDS) patients by lowering the viral charge and increasing the number of CD4-positive T cells, thus contributing to the restoration of the patients' immune system.27, 28 In addition to their anti-viral benefits, the efficacy of HIV-PIs to decrease AIDS-associated Kaposi sarcoma29, 30 has raised interest in their distinct antitumor properties.