A phenomenon known as Immune Discordance has been well known. It reflects a subpopulation -as high as 30% of patients- in whom there is an adequate suppression of viral replication, but CD4+ cell levels rise modestly (below safety levels). In this setting, patients remain susceptible to develop opportunistic infections, have disease progression, and die. Various mechanisms have been proposed, but one common factor is enhanced CD4+-cell activation, leading to cell dysfunction and apoptosis.