Low CD4+ T Cell Nadir Is an Independent Predictor of Lower HIV-Specific Immune Responses in Chronically HIV-1–Infected Subjects Receiving Highly Active Antiretroviral Therapy

The influence of CD4 + T cell nadirs on human immunodeficiency virus (HIV)-specific immune responses in subjects with apparently normal CD4 + T cell counts is not known. We evaluated the frequency of HIV-1-specific immune responses in a cohort of patients with complete viral suppression (HIV-1 RNA load, <50 copies/mL) who were receiving highly active antiretroviral therapy and had a wide range of CD4 + T cell nadirs. We found positive associations between CD4 + T cell nadirs and the magnitude of HIV-specific CD8 + T cell responses (P =.02) and of T cell helper responses (P =.04). These data show the CD4 + T cell nadir to be an independent predictor of HIV-specific CD4 + and CD8 + T cell responses in HIV-1-infected subjects with optimal suppression of viremia.