STUDIES ON A POSSIBLE ANTIGENIC RELATIONSHIP BETWEEN GONADOTROPHINS AND BLOOD GROUP SUBSTANCES

Abstract

ABSTRACT Precipitation reactions could not be demonstrated between antisera to human erythrocytes of A, B and O groups and chorionic gonadotrophin (HCG), menopausal gonadotrophin (HMG), pregnant mares' serum gonadotrophin (PMS) and animal pituitary follicle stimulating hormone (FSH-P). Blood group activity was present in the gonadotrophin extracts but could not be attributed to the hormone. The blood group substances present in the gonadotrophic extracts caused a low titre of haemagglutinins to appear in potent antigonadotrophic sera. Absorption with A, B and O erythrocytes did not lower the haemagglutination titre of anti-HCG serum when tested against HCG-sensitised cells. The antisera to the erythrocytes did not affect the response to HCG in rats but caused partial inhibition of the effects of HCG, HMG and PMS in mice. The latter result was not thought to be the result of an immunological reaction. It was concluded that gonadotrophins do not possess blood group A, B, or O(H) specificity.