Epitope characterization. (A) Binding affinity of each peptide to HLA-A*24:02 was tested by using T2-A24 cell line. All peptides except negative control peptide, VPLDKDFRKY, which might not bind to HLA-A*24:02, show HLA-A*24:02 binding in the peptide concentration of 10-4 M. Each point and bar represents the average and the standard deviation of normalized MFI from three independent experiments. (B) 293FT-A24DRm-CY0 cells were pulsed with serially diluted peptides and co-cultured with CTL clones specific to Nef134-10 (H27-9) or Nef126-10 (I30-1). Epitope recognition was determined by normalizing quantity of IFN-γ secretion. For normalization, all values were divided by IFN-γ secretion with wild type peptide concentration of 9 μM. Neither clone showed specificity to the negative control, Gag28-9 peptide (KYKLKHIVW) a binder of HLA-A*24:02. Each point and bar show average and standard deviation of three independent experiments.