FIG. 3.

Characterization of the T-cell responses to epitope variants AL9/B62 in subject 1212 (top panel), AL9/Cw08 in subject 1238 (middle panel), and WF9/B1503 in subject 1188 (bottom panel). A standard IFN-γ ELISPOT assay was performed by stimulation with the optimal epitopic peptides and variants at serial concentrations between 10,000 and 0.1 ng/ml. Shown here are PBMC responses from subjects 1238 and 1212 (AL9 epitope variants) and subject 1188 (WF9 epitope variants). The SFC frequencies were plotted against the log₁₀ peptide concentration, and the effective peptide concentration that elicited 50% of the maximum T-cell response was determined using ORIGIN 6.0 professional software. Epitope mapping and HLA restriction data were published previously (9).