T cell responses to recall antigens, alloantigen, and mitogen of HIV-infected patients receiving long-term combined antiretroviral therapy

The effect of highly active antiretroviral therapy (HAART) on T cell respon ses in 30 HIV-infected patients was studied. Lymphocyte proliferation in re sponse to influenza A virus, HIV-1 p24, gp160, allogeneic leukocytes, and m itogen, as well as influenza-specific cytotoxic T lymphocyte (CTL) response s, were measured. AIDS patients had decreased T cell-proliferative response s to influenza and alloantigen compared with asymptomatic patients. Absence of positive proliferative responses of HIV-infected patients to HIV-1 anti gens was not associated with increased interleukin 10 production. Correlati on was observed between influenza-specific CTL response and T cell prolifer ation, as well as CD4(+) T lymphocyte counts, indicating the importance of CD4(+) helper T cells for generating antiviral CTL responses. Finally, thes e results show that HAART-treated asymptomatic patients, but not AIDS patie nts, have T cell responses comparable to those of control individuals. It r emains to be determined whether immune-based therapy will contribute any ad ditional benefit to patients who received HAART.