Human Endogenous Retrovirus K(HML-2) Gag- and Env-Specific T-Cell Responses Are Infrequently Detected in HIV-1-Infected Subjects Using Standard Peptide Matrix-Based Screening

T-cell responses to human endogenous retrovirus (HERV)K(HML-2) Gag and Env were mapped in HIV-1-infected subjects using 15mer peptides. Small peptide pools and high concentrations were used to maximize sensitivity. In the 23 subjects studied, only three bona fide HERV-K(HML-2)-specific responses were detected. At these high peptide concentrations, we detected false-positive responses, three of which were mapped to an HIV-1 Gag peptide contaminant. Thus, HERV-K(HML-2) Gag-and Env-specific T-cell responses are infrequently detected by 15mer peptide mapping.