Induction of cell-mediated cytotoxic immunity to sperm-specific lactate dehydrogenase-C4 in SJL/J female mice.

SJL/J female mice were tested for a cell-mediated cytotoxic response to sperm-specific lactate dehydrogenase C4 (LDH-C4). We demonstrated this response with a 51chromium release assay. Mouse LDH-C4 was coupled to EL-4 tumor cells. These cells were then labeled with 51Cr and mixed with splenocytes from LDH-C4-immune and -nonimmune mice. Specific lysis of the tumor cells by splenocytes from LDH-C4-immune mice was detected at 7 days and 14 days following a single footpad immunization. Since LDH-C4 is present on the surface of sperm, these results support the suggestion that cytotoxic removal of sperm from the female reproductive tract is one of the mechanisms whereby fertility is reduced following immunization with this enzyme.