An increase in RA9-specific CD8 T cells was observed for most animals following the first infection with H1N1 (PR8) influenza which was boosted following inoculation with H3N2 (X-31) influenza at day 28; with the number of RA9-specific CD8 T cells in animal B0527 increasing from 0.08% at day 28 to 0.44% at day 35 (Figure 4c). This evidence concerns the gene CD8A and infection.