Decreased HIV-specific CD4 T cell proliferation in long-term HIV-infected individuals on antiretroviral therapy.

The effect of highly active antiretroviral therapy (HAART) on HIV-specific CD4 T cell proliferation in long-term HIV-infected individuals was studied. Subjects receiving treatment for over a year were compared with individuals not receiving therapy. The absolute number of HIV-specific memory CD4 T cells proliferating in response to HIV antigen was substantially higher in untreated subjects than in those on HAART. A decrease in HIV-specific memory CD4 T cells could explain the rebound in HIV replication after the termination of HAART.