Peptide vaccine--a new approach to a safer foot-and-mouth disease virus vaccine.

: A synthetic peptide, of which the region of the major antigenic determinant of foot-and-mouth disease virus serotype O1K located on the coat protein VP1 consists, was coupled to different protein carriers. Comparing the potency of the conjugates to elicit neutralising antibodies it has been shown that KLH was the best carrier protein. Using different amounts of peptide A (aa 144-aa 159) the dependence of neutralising antibody response on the amount of injected peptide has been demonstrated. Peptide A was shown to be located in the C-terminal part of a highly variable region when the protein sequences of different sero- and subtypes were compared. Comparative evaluation of peptide A with two longer peptides G1-21 and G1-31 (aa 140-aa 160 and aa 129-aa 160) suggests that the N-terminal part of the highly variable region before amino acid 144 is not necessary to obtain a protective response, but it is necessary to enhance the immune response when the peptides are used uncoupled.