Antiretroviral therapy influences cellular susceptibility to apoptosis in vivo.

It has been proposed that antiretroviral therapies (ART) possess both antiviral and immunomodulatory activities when used in HIV infected patients. Few studies have addressed whether these putative immunomodulatory effects are also seen in HIV negative patients, for example, when used for post exposure prophylaxis (PEP). We chose to evaluate immunologic function in HIV negative patients who received Nelfinavir and Combivir (AZT and 3TC) as PEP. Lymphocytes from patients taken immediately before, during, and after PEP were analyzed. No changes were seen in absolute or percent CD4 or CD8 T lymphocyte numbers, nor in markers of activation, memory, or co-stimulatory molecules. Surface expression of apoptosis-related ligands and receptors were unaltered, but apoptosis susceptibility was significantly inhibited by PEP (P less than 0.05). These data confirm in vitro that apoptosis susceptibility is altered by ART, including in HIV-negative patients who take PEP.