Figure 2. Magnitude of responses (A) and response rates (B) to the set of overlapping peptides covering all of Nef and the set of polyallelic peptides identified as HLA-restricted epitopes within Nef.

There were no significant differences in the magnitude of responses (A) detected by the panel of tested polyallelic peptides (△, median=120 SFUs/10⁶ PBMCs) compared to the overlapping peptides (▽, median=132 SFUs/10⁶ PBMCs). Each of the two peptide sets were split to further focus on common peptide sequences: embedded polyallelic peptides were those sequences contained within an overlapping peptide; encompassing overlapping peptides were those which contained at least one embedded polyallelic peptide within the longer sequence. Similar response rates (p=0.5) were obtained for peptide sequences common to sets (B). However, a significantly higher number of overlapping peptides elicited a response when the peptide contained an embedded polyallelic epitope than if no polyallelic peptide was present in the overlapping peptide sequence (p=0.0002).