Effect of Human Seminal Plasma on the Lytic Activity of Natural Killer Cells and Presumptive Identification of Participant Macromolecules


Department of Urology, Health Sciences Center, SUNY at Stony Brook, Stony Brook, NY 11794-8093.


ABSTRACT: Using the lytic activity of natural killer (NK) cells as an in vitro parameter, the immunoregulatory properties of human seminal plasma (SeP1) and participant macromolecules have been investigated. Significant (P < 0.05) suppression of NK cell activity by SeP1 and chromatographically separable fractions was demonstrated in association with high and low molecular weight (Mr) macromolecules. SePl suppression was retained after heating to 56°C for 30 min, and appeared to function at the level of the effector, rather than target cell. Physicochemical characterization of high and low Mr fractions provided presumptive identification of the participation of transglutaminase and prostaglandins as the principal molecules contributory to SeP1 immunosuppression.