Human Immunodeficiency Virus (HIV)–Specific Effector CD8 T Cell Activity in Patients with Primary HIV Infection

The interferon-gamma ELISPOT assay was used to assess and compare the magnitude and breadth of human immunodeficiency virus (HIV)-specific CD8 T cell responses in treatment-naive subjects during the first year of HIV primary infection and during the chronic phase of infection. Twenty-five subjects tested within a year of exposure to HIV resulting in seroconversion and 20 subjects with chronic infection were screened for HIV peptide-specific activity by stimulating peripheral blood mononuclear cells with a panel of 5-21 HLA class I-restricted HIV peptides (mean, 11.2 +/- 3.5 HIV peptides). There was a significant correlation between the magnitude and breadth of HIV-specific effector responses and time elapsed from exposure (r=0.63 for magnitude vs. time and r=0.64 for breadth vs. time; P<.02, paired t test). Maximal breadth of the HIV gene product reactivity was achieved within 2 months of exposure for Nef-specific responses and by 4 months of exposure for responses directed to Env, Gag, and reverse transcriptase.