HIV infection is known to cause profound and irreversible dysfunction of both innate and adaptive arms of the immune system. However, there is mounting evidence that early and aggressive treatment with antiretroviral drugs can prevent loss of immune cell function. In an attempt to further delineate the effect of early antiretroviral therapy (ART) on maintenance of immune cell function, we wish to recruit drug-na(SqrRoot) ve HIVinfected patients who are either in early or chronic stage of infection. The study will require that patients undergo leukapheresis or research blood draw once before and several times after enrollment. Leukapheresis will be used in order to obtain sufficient cells to pursue the following objectives: delineating B cell response to CD4+ T cell help, delineating the effect of ART on persistent HIV reservoirs in CD4+ T cells of infected individuals, and delineating CD8+ T cell-mediated suppression of viral replication and normalization of immune function, and characterizing natural killer (NK) function relative to HIV disease. The required number of mononuclear cells needed to perform these experiments can be easily and safely obtained using leukapheresis procedures in the Clinical Center Apheresis Unit. This protocol is specifically designed to conform to the requirements of the Apheresis Unit for donors to have leukapheresis procedures, but the protocol, by itself, is not an independent research study. Alternatively, whole blood draws will be used in cases where patients are unable to undergo leukapheresis. While this approach will limit extensive functional analyses, informative phenotypic and limited functional analyses can nonetheless be performed.