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.
