Immune responses of swine inoculated with a recombinant fowlpox virus co-expressing P12A and 3C of FMDV and swine IL-18.

Two recombinant fowlpox viruses (rFPV-P1 and rFPV-IL18-2AP12A) containing foot-and-mouth disease virus (FMDV) capsid polypeptide, 3C coding regions of O/NY00 were evaluated to determine their abilities to induce humoral and cellular responses in the presence or absence of swine IL-18 as genetic adjuvant. The ability to protect swine against homologous virus challenge was examined. All swine were given booster vaccinations at 21 days after the initial inoculation and were challenged 10 days after the booster vaccination. Control groups were inoculated with wild-type fowlpox virus (wtFPV). All animals vaccinated with rFPV-P12A and rFPV-IL18-P12A developed specific anti-FMDV ELISA antibody and neutralizing antibody and T-lymphocyte proliferation was observed. Cellular immune function was evaluated via examination of IFN-γ production in swine peripheral blood serum. The results demonstrate the potential viability of a fowlpox virus-based recombinant vaccine in the control and prevention of FMDV infections.