Reversible contraceptive effect of PH-20 immunization in male guinea pigs

• Published in: Biology of reproduction 1997-05, Vol.56 (5), p.1142-1146
• Main Authors: Primakoff, P, Woolman-Gamer, L, Tung, K S, Myles, D G
• Format: Article
• Language: English
• Subjects: Animals; Antibody Formation; Antigens - administration & dosage; Biological and medical sciences; Birth control; Cell Adhesion Molecules - administration & dosage; Cell Adhesion Molecules - immunology; Contraception, Immunologic - methods; Female; Guinea Pigs; Gynecology. Andrology. Obstetrics; Hyaluronoglucosaminidase; Immunization; Infertility, Male - etiology; Infertility, Male - immunology; Male; Medical sciences; Other methods of contraception. Sterilization; Pregnancy; Spermatozoa - immunology; Time Factors
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod56.5.1142

Sperm proteins are currently being studied as antigens on which to base a contraceptive vaccine. Sperm plasma membrane proteins offer the theoretical possibility of immunizing either males or females and achieving a contraceptive effect. In this study, we investigated the sperm plasma membrane protein PH-20 as an antigen for inducing infertility in males. We found that infertility can reproducibly be induced in male guinea pigs immunized with purified PH-20: 100% (29 of 29) of PH-20-immunized males became infertile, whereas all 22 controls were fertile. The males were extremely responsive to PH-20 immunization: infertility could be induced with a single injection of only 5 microg PH-20. Among males that received their initial injection when they were approximately 300 g (body weight), 14 of 15 had regained fertility at about 1 yr after initial injection. Surprisingly, in another group of males that received their first injection when they were approximately 650 g (body weight), only 1 of 5 had regained fertility about 1 yr after initial injection. Anti-PH-20 titers in antisera (2 mo after initial injection) were generally in the range 1.1-4.2 x 10(4) in twice-injected males and the range 1.8-9.4 x 10(3) in once-injected males. Over the next 6-11 mo, twice-injected males' titers decreased > or = 4-fold, whereas once-injected males' titers decreased slightly (1.1 - to 1.8-fold). After 6-11 mo, anti-PH-20 titers were in the range 1.0-4.8 x 10(3), and the precise residual titer did not correlate with fertility/infertility. The results show that immunization of males with PH-20, even at low doses, results in a reproducible, completely effective contraceptive action.