The immediate initiation of ART therapy in patients with advanced disease could in fact result in a rapid improvement of abnormalities related to defects in proliferation and apoptosis and, even if there is not a rapid response in terms of increase in CD4+ T-cell count, a significant improvement in the quality of immune response, which clinically may account for the improved survival observed in patients affected by full-blown AIDS and opportunistic infections, once they start receiving ART. Here, CD4 is linked to AIDS.