Functional virus-specific T-cell responses to E6. IFN-γ production was measured in an ELISPOT assay after preventive immunization to detect CD8+ T-cells after specific antigenic stimulation with the E6 protein and peptides. The numbers of IFN-γ-secreting spot-forming cells (SFCs) were determined after subtracting the values obtained using the scFv unrelated protein. Data are presented as fold-increased responses to the E6-specific protein and peptides. G2 and G3 are the protocols for the DNA/FP and FP/FP prime/boost vaccinations, respectively. Statistical significances using the ANOVA parametric test are shown: **p <0.01; ***p <0.001.