Distribution of epitopes recognized by expanded CD4⁺ and CD8⁺ T cells. T-cell lines were expanded from the blood of 13 chronic HIV⁺ subjects by coculture with LysoNef-transfected DCs. Individual OLPs recognized by each line were identified by ELISpot; each epitope was categorized as being recognized by CD4⁺ or CD8⁺ T cells by ICS or by ELISpot following specific depletion with anti-CD4 or -CD8 beads. The relative frequency of recognition was calculated for each of the 27 Nef OLPs. For comparison, the distribution of responses in expanded T cells was compared with the ex vivo responses detected in the PBMCs of 347 chronic HIV⁺ subjects. (A) The distribution of CD8 and CD4 responses in the DC-expanded T-cell lines. (B) Expanded CD8 responses from the 13 lines were compared with ex vivo responses in PBMCs of 347 chronic subjects and expanded CD4 responses. (C) The frequency of CD8 but not CD4 responses is inversely correlated to OLP entropy. For each OLP, the frequency of recognition was plotted against the average Shannon entropy score for amino acids within the OLP. Entropy values were calculated as previously described.²⁷