HIV-1 ASP peptide pools activate IFN-γ T cell responses in a cohort of HIV+ individuals. The magnitude of IFN-γ ELISpot responses (SFU/106 PBMCs) to the Gag or ASP pools and subpools (1 to 9, and A to J) are shown for (A) seronegative donors and (B) HIV-1+ patients. Each dot represents one donor and mean IFN-γ responses of triplicate or quadruplicate are indicated. The dashed line marks the standardized threshold (55 SFU/106 PBMCs) for positivity. (C) PBMCs were assessed for IFN-γ production using ASP pools and 19 ASP subpools. Mann–Whitney U tests were performed to determine significant differences between the median responses to peptide pools (p < 0.01). (D) The frequency of responders is illustrated as a proportion of seronegative (SN) or seropositive (HIV+) individuals with positive responses to the Gag pool (blue column) and either to the ASP pool or any ASP subpool (red column).