Significance of specific ovarian receptors for syngeneic naturally-occurring haemagglutinating anti-A antibodies.

Haemagglutinins which specifically combine with membrane determinants of human blood group A erythrocytes and which are distinguishable from any other haemagglutinin specificities display marked sex dependency in C57BL/10 mice. All the sera of 80-day-old C57BL/10 females exert moderate to strong anti-A haemagglutinin activities which could be detected only in approximately half of the sera of the males of the same age. Investigations of the murine tissues revealed that the production of anti-A haemagglutinins in females is reflected by simultaneous synthesis of strong endogenous receptors detected in the ovaries and associated with water-soluble glycolipid fractions. The receptor activity was demonstrated by means of haemagglutination inhibition in comparison with appropriate controls and glycolipid preparations from seventeen other different male and female tissues, and the inhibitory effects exerted by the ovarian glycolipids were statistically significant on the basis of multiple comparisons at the 1% level in each possible pair of effects.