Figure 3.

The VP1 protein and the VP1-gp120 and VP1-E2 fusion proteins induced the production of specific anti-FMDV IgG antibodies in guinea pig serum (each group contained 5 guinea pigs, n = 5). Serum samples were collected from all guinea pigs at 7 days after booster immunization, and the specific anti-FMDV IgG antibody levels were determined by indirect ELISA. PBS/ISA 206 mixture was used as the negative control (n = 5), and the commercially available inactivated vaccine was used as the positive control (n = 5). Significant values (^∗P < 0.05) are indicated by an asterisk.