Figure 6. Cell-mediated responses elicited by vaccination.

HLA-A2k^b transgenic mice (n = 3 per group) were inoculated (100 µl) subcutaneously at the base of the tail on days 0 and 14 with 30 µg of VLPs alone, emulsified with an equal amount of complete freund’s adjuvant (CFA) or pre-mixed with 30 µg of E₈Pam₂Cys in saline. Splenocytes were obtained 28 days later and restimulated for 7 days in the presence of 10 µg VLPs or an irrelevant HCV-derived HLA-A2-restricted epitope not part of the VLP construct. The frequency of peptide-specific T cells producing IFN-γ was determined in an ELISPOT assay. Each bar represents the average number of IFN-γ producing T cells and standard deviation in each group after subtracting non-specific responses from corresponding samples stimulated with the irrelevant peptide.