RESPONSE OF CYNOMOLGUS MACAQUES TO IMMUNIZATION AGAINST A SYNTHETIC PEPTIDE FROM THE HUMAN ZONA-PELLUCIDA

This study tested immunogenicity of a synthetic peptide hZP3(327)-(341 ) from a human zona pellucida (ZP) glycoprotein, After antibody respon se to various peptide-carrier conjugates was assessed in mice, two fem ale cynomolgus macaques were immunized with the peptide conjugated to keyhole limpet hemocyanin (KLH). A control macaque was immunized with KLH. The peptide was immunogenic in both species, and included both B and T cell epitopes since low to moderate titers of peptide-specific a ntibodies and a T cell proliferative response were measured, Profiles of ovarian steroid metabolites indicated unchanged ovarian function in the macaques, but only the control conceived when bred, Ovarian histo logy was normal except that immunoglobulin was bound to ZP in follicle s of the peptide-immune macaques, ZP from these females bound sperm an d induced acrosome reactions at rates equal to those of an untreated c ontrol, The results support the feasibility of an immunocontraceptive vaccine based on autologous ZP peptides.