Antifertility effects of immunoglobulins from uterine fluids of semen-immunized rabbits.

Abstract

The effects on fertility of the immunoglobulins, IgG (similar to serum IgG) and secretoy IgA (the predominant IgA in uterine fluid, different from serum IgA) and the fluids from the uteri of semen-immunized rabbits were studied. Female rabbits were immunized either by transvaginal (TV) injections (every 4 or 5 days for 3 weeks) with adjusted semen added to buffered saline containing .5 mg each polyadenylic acid )Poly-A) and polyuridylic acid or a combination of transvaginal injections and systemic injections with rabbit semen mixed with adjuvant (each once weekly for 3 weeks). 2 weeks following the last injection of semen each rabbit received a TV injection followed in 1 week by an instillation of semen and Poly A and U into uterine horns ligated at both ends. 2 weeks following intrauterine (IU) instillation uterine contents were withdrawn. Uteri were reinstilled. Passive hemagglutinating (PHA) and sperm-immobilizing antibody titers were determined on both serum and adjusted uterine fluid (UF) samples. Sperm immobilizin tests and PHA were positive in all serum samples from the contained immunization group, and PHA were positive in 4 out of 7 UF samples of this group. 2 out of 10 and 3 out of 10 samples from the TV group were positive for SI and PHA, respectively, and 4 out of 10 UF samples were PHA positive. Treatment of rabbit semen with UF samples prior to insemination of estrous rabbits resulted in an implantation rate of 2.8% for the combined immunization group and 24.2% for the TV group compared to 79.2% for controls. Some IUF samples without detectable antibodies appeared to inhibit fertility. The implantation rate of sperm treated with immune UF from the TV group absorbed with goat normal serum, anti-rabbit gamma-globulin serum, anti-rabbit-secretory IgA serum, anti-rabbit IgG serum, or sperm, were 3.4%, 88.9%, 42.9%, 64%, and 73. 3% respectively. SIgA and IgG antibodies were seperated by gel filtration. 2 of 4 pooled IgA samples and 3 of 4 pooled IgG samples depressed fertility, with 24.3% and 22.6% implantation and 25.8% 5, and 0% implantation, respectively. To assure that the antifertility effects observed were due to sperm antibodies of each immunoglobin class, SIgA fractions of 2 IUF pools were subjected to anion-exchange chromatography, and both SIgA and IgG fraction were absorbed with goat NS, anti-SIgA, and anti-IgG. IgG fractions absorbed with anti-SIgA or anti-IgG resulted in implantation rates of 0% and 56.8%, respectively, compared to a control of 89.5%. SIgA fractions absorbed with anti-SIgA or anti-IgG resulted in implantation rates of 81.8% and 19.4%. Thus IgG and secretory IgA of the uterine fluids are active in inhibition of fertility.