The effects of soluble products from leukocytes (WBC) on sperm motility and calcium ionophorestimulated acrosome reaction (AR) were examined. Supernatants of mononuclear WBC, isolated from peripheral blood and stimulated by the lectins Phyfolacca americana (pokeweed mitogen) or concanavalin A, caused a weak but significant inhibition of progressive sperm motility. The recombinant cytokine interferon-y (IFN-y) in high concentrations inhibited motility of sperm from 5 of 8 donors tested. The recombinant cytokines tumor necrosis factor-a (TNF-a) and interleukin-8 (IL-8) did not show any effect on sperm motility. Reactive oxygen species (ROS) produced by stimulation of polymorphonuclear WBC with a phorbol ester (PMA) tended to inhibit sperm motility. Neither supernatants from lectin-stimulated mononuclear WBC, IFN-y, TNF-a, IL-8, nor ROS showed any significant effect on the ionophore-challenged AR. acrosome reaction, sperm motility, cytokines, reactive oxygen species, lectins, human
KeywordsHigh concentration of leukocytes in semen may be a causative mediator of otherwise unexplained infertility [ 151. Cytokines produced by these cells could be responsible for the effect. Thus, in a few studies an inhibiting role has been found of the cytokines interferon-? (IFN-y) and tumor necrosis factor-a (TNF-a) on motility of human sperm [ 14, 181 and on penetration rate in the hamster oocyte test [17],The cytokine interleukin-8 (IL-8) stimulates chemotaxis of human polymorphonuclear granulo-