PRIMATE RESPONSE TO IMMUNIZATION WITH A HOMOLOGOUS ZONA-PELLUCIDA PEPTIDE

Development of a contraceptive vaccine using zona pellucida (ZP) antig ens has been hampered by the observation that the immune response to t he antigens results in altered ovarian function and depletion of the f ollicular pool of oocytes. The amino acid sequences of many ZP protein s have been determined in the past decade allowing study of fully synt hetic peptide immunogens based on these ZP sequences. Such immunogens permit a precisely targeted response. The non-human primate is the bes t model for predicting how women may respond to ZP peptide vaccines. C ynomolgus macaques (Macaca fascicularis) have been immunized with synt hetic peptides comprising a human ZP3 epitope and a macaque homologue of the same epitope. In both studies, immune response to the peptides was initiated, and infertility was accompanied by normal ovarian funct ion.