Immune reconstitution after a decade of combined antiretroviral therapies for human immunodeficiency virus

The introduction of combined antiretroviral therapies (HAART) has reversed the fatal course of human immunodeficiency virus (HIV) infection. HAART controls virus production and, in most cases, allows the quantitative and functional immune defects caused by HIV to be reversed. Here, we review T cell homeostatic mechanisms that drive immune recovery. These homeostatic mechanisms, as well as differences in T cell antigen exposure, explain the distinct patterns of recovery for HIV-specific T cells versus T cells specific for other pathogens. Immune restoration during HAART can, however, have adverse effects. Immune restoration syndrome occurs in some patients as a result of successful but unbalanced immunity.