Sex dependent immune responses by allogenic LDH isozymes.

Regulatory effects on polyclonal activation of primed splenocytes have been studied following immunization through the intrarectal route with allogenic sperm specific lactate dehydrogenase (LDH-C4) and somatic LDH from kidney. Results indicate that LDH primed cell proliferation by mitogens is dependent on the nature of the isozyme and sex of donor cells. Compared to somatic LDH, LDH-C4 was immunosuppressive for T cell proliferation in vitro and the effect was more significant with female splenocytes as compared to male spleen cells. However, the suppressive effect of LDH-C4, on B cell function was identical in both males and females. In contrast to the somatic LDH which did not produce alloantibody in significant amount, LDH-C4 was highly immunogenic in production of humoral antibody in female mice. Alloantibody formation in dams was substantiated with a similar degree of immune regulation of B cell functions as shown by lipopolysaccharide stimulation. The role of LDH-C4 in protection of allogenic sperm in the female genital tract has been suggested. However, it is concluded that recipients of sperm constituents through the intrarectal route are at greater risk for immune suppression and bacterial/viral infection.