Synthetic vaccine against foot-and-mouth disease based on a palmitoyl derivative of the VP1 protein 135-159 fragment of the A22 virus strain.

The peptide Palm2 135-159, a dipalmitoyl derivative of the 135-159 fragment of VP1 protein of the foot-and-mouth disease virus strain A22 was synthesized. In the experiments on mice, guinea pigs and sheep Palm2 135-159 possesses greater immunogenic and protective activity than the nonacylated 135-159 peptide. The synthetic vaccine against foot-and-mouth disease for use in sheep was developed on the basis of the lipopeptide. Synthetic polymethylsiloxane oil was found to be a suitable adjuvant for this vaccine. The dependencies of protective and immunogenic effects from the dose of peptide were studied. The vaccine was found to be stable to storage for 1 year at 18 degrees C. It was shown that the synthetic vaccine provides 1 year protection of sheep against foot-and-mouth disease after a single administration. The vaccine is allowed for veterinary use in Russia.

New virus-specific T-helper epitopes of foot-and-mouth disease viral VP1 protein.

Immunogenicity studies of synthetic peptides from different regions of VP1 protein of foot-and-mouth disease virus strain A22 revealed the following active fragments: 39-61, 50-69, 135-159, 175-189, 170-189 and 197-213. Testing of virus neutralizing antibody production in rabbits primed by peptides and then inoculated by the virus showed that only peptides 135-159 and 170-189 were able to induce the functional T-cell helper activity. Localization of virus-specific T-cell recognition sites in sequences 135-159 and 170-189 was confirmed in in vitro recognition experiments of the virus by peptide activated mice lymphocytes.