Contraceptive effect of sperm-agglutinating monoclonal antibodies in rabbits.
Immune infertility in humans correlates clinically with the presence of anti-sperm antibodies that trap (agglutinate) sperm in semen and cervical mucus. To test whether sperm-agglutinating antibodies can be effective contraceptive agents, several mouse anti-rabbit sperm (MARS) sperm-agglutinating monoclonal antibodies (mAbs) were developed that rapidly and completely agglutinate sperm: MARS-M3 (IgM), MARS-G16 (IgG3), and MARS-G17 (IgG3). Contraceptive efficacy of these mAbs was tested by mixing the mAb with 0.1 ml semen (approximately 1/5 of a whole ejaculate) immediately before artificially inseminating rabbits paracervically. This paracervical dose of semen provided a rigorous test since it delivered several thousand times more fertilizing doses than does a human ejaculate. All of the mAbs were contraceptively effective, and MARS-G16 reduced the number of fetuses per animal by 88% and 95% with doses of 150 microg and 2 mg, respectively. The contraceptive efficacy of the MARS mAbs in the rabbit suggests that human sperm-agglutinating mAbs may be effective agents for vaginal contraception in humans.
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Thomas C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Whaley
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Hoen
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Moench
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D000818:Animals; D000911:Antibodies, Monoclonal; D000941:Antigens / Q000276:immunology; D015153:Blotting, Western; D003165:Complement System Proteins / Q000276:immunology; D003269:Contraception, Immunologic; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D007116:Immunization, Passive; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D013073:Sperm Agglutination; D013094:Spermatozoa / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000941:Antigens; D003165:Complement System Proteins