Efficacy of synthetic peptide candidate vaccines against serotype-A foot-and-mouth disease virus in cattle

Foot-and-mouth disease (FMD) remains a major threat to livestock worldwide, especially in developing countries. To improve the efficacy of vaccination against FMD, various types of vaccines have been developed, including synthetic peptide vaccines. We designed three synthetic peptide vaccines, 59 to 87 aa in size, based on immunogenic epitopes in the VP1, 3A, and 3D proteins of the A/HuBWH/CHA/2009 strain of the foot-and-mouth disease virus (FMDV), corresponding to amino acid positions 129 to 169 of VP1, 21 to 35 of 3A, and 346 to 370 of 3D. The efficacies of the vaccines were evaluated in cattle and guinea pigs challenged with serotype-A FMDV. All of the vaccines elicited the production of virus-neutralizing antibodies. The PB peptide, which contained sequences corresponding to positions 129 to 169 of VP1 and 346 to 370 of 3D, demonstrated the highest levels of immunogenicity and immunoprotection against FMDV. Two doses of 50 mu g of the synthetic PB peptide vaccine provided 100 % protection against FMDV infection in guinea pigs, and a single dose of 100 mu g provided 60 % protection in cattle. These findings provide empirical data for facilitating the development of synthetic peptide vaccines against FMD.