CD4⁺ and CD8⁺ T-cell depletion experiments. IFN-γ ELISpot on PBMCs, or CD4- or CD8-depleted fraction of PBMCs (CD4⁻CD8⁺ or CD4⁺CD8⁻, respectively). Samples were collected at week 19 (subject A) and week 12 (subject D). Results are expressed in SFU/10⁶ cells as average (± SD) of 3 replicates. Peptide 79/80 indicates 15-mers previously identified in subject A by screening ELISpot; peptide 49, 15-mer previously identified in subject D by screening ELISpot; medium, negative control; and PMA, positive control (PMA and ionomycin).