IFN-γ production in the supernatant of splenocytes harvested from immunized mice after in vitro restimulation. Mice were immunized as in Figure 4. Splenocytes were isolated 7 weeks after primary immunization and were restimulated in vitro with 146S antigen of FMDV for 20 h. IFN-γ production in the supernatant was analyzed by ELISA. Data represent the mean ± SD. Pos, Neg, or PBS denotes mice vaccinated with 100 μL inactivated vaccine, 1 × 1010 PFU of Bac-GED, or 100 μL of PBS.