Problem: The development of a new and suitable contraceptive methods, as well as in-depth and systematic research into underlying contraceptive mechanisms, is crucial. IZUMO1 plays an important role in the fusion of the sperm and ovum during fertilization. Izumo(-/-) mice are infertile. Therefore, IZUMO1 may be a potential target for the development of a contraceptive vaccine.
Method of study: Linear B-cell epitopes (BCE) were identified in IZUMO using biosynthetic peptides and used to immunize female mice.
Results: Five IZUMO BCE were identified: DLVLDCL177-183, YSFYRV196-201 (named BCE-2), YLT217-219, SMVGPED221-227, and DAGNY228-232. Active immunization with the BCE-2 vaccine sharply decreased the fertility rate in female mice in a safe and reversible manner. In vitro fertilization showed that the BCE-2 vaccine interferes with and blocks the fusion of the sperm and the ovum.
Conclusions: B-cell epitopes-2 may be a new candidate for the development of contraceptive vaccine due to its effectiveness, safety, and reversibility.
Keywords: IZUMO; linear B-cell epitope; peptide vaccine; sperm antigen; sperm-egg fusion.
© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.