Figures 5A–C show the percentage of cytokine-producing T cell subsets for which significant differences were observed between groups before vaccination (D0), after vaccination (D7 and D21) or after challenge infection (D49). After vaccination, a higher percentage of TNF-α+ CD8+ T cells was detected in V1 as compared to V2 (D7) and C (D21), while after challenge (D49) significant differences were no longer present. For the percentage of TNF-α+ CD8+ T cells, a significant difference was observed for D7 and D21 as compared to D0 in V1. This evidence concerns the gene CD8A and infection.