ENHANCED IMMUNOGENICITY AND CROSS-REACTIVITY OF RETRO-INVERSO PEPTIDOMIMETICS OF THE MAJOR ANTIGENIC SITE OF FOOT-AND-MOUTH-DISEASE VIRUS

Retro-inverso analogues of peptides corresponding to the major antigen ic site 141-159 of VPI from two foot-and-mouth disease virus variants have been synthesized and tested for their antigenic and immunogenic p roperties. Antibodies to the L- and retro-inverso peptides were produc ed by injecting rabbits with peptides covalently coupled to small unil amellar liposomes containing monophosphoryl lipid A as adjusvant. When compared to the antibody response raised against the L-peptides, the duration of the IgG response that was induced bq the retro-inverso pep tides was significantly longer and the titer of anti-peptide antisera was much higher. Antibodies to retro-inverso peptides cross-reacted eq ually well with the respective parent L-peptides. These results, obtai ned with a viral sequence which, was found previously to represent a g ood candidate for possible vaccination, show that retro-inverso peptid omimetics could be useful for enhancing the immunogenicity of peptides .