Enhanced Suppression of Fertility Can be Achieved by Priming with FSHR and Eppin and Further Boosting with Their B-cell Epitope Peptides.

Abstract

In our previous study on adult male mice, we had identified one immunodominant epitope in hEppin and three epitopes in hFSHR that caused fertility inhibition. But it only demonstrated a moderate inhibitory effect on fertility, and the antifertility effect was unsatisfactory. Based on the protein prime-peptide boost inoculation modalities, we further investigated whether the antifertility capacity could be enhanced by a combined immunization with the two antigens. The results displayed a enhanced suppressed fertility (F2EP2C 6.67%) in male mice similar to that seen after four separate administrations of the two proteins (F12E-4 5%). The most likely mechanism by which this antifertility efficacy was achieved was probably through the production of antibodies that led not only to impairment of spermatogenesis but also to inhibition of sperm motility. Moreover, this treatment also induced high concentrations of neutralizing antibodies which were secreted into the lumen of the epididymis. Thus, a combination immunization with hFSHR and hEppin enhanced the contraceptive effects and may provide a better means of immunocontraception.