Seminal plasma components stimulate interleukin-8 and interleukin-10 release.

Human seminal plasma has potent anti-inflammatory properties which are thought to confer a survival advantage to the spermatozoa within the hostile female genital tract. In contrast, a profound pro-inflammatory leukocytosis has been observed post-coitus in animals and humans. Whether components of seminal plasma are involved in initiating this leukocytic reaction is not known. This study investigated the effect of human seminal plasma, a seminal plasma fraction and its principal constituent prostaglandins, prostaglandin E2 (PGE2) and 19-hydroxy PGE, on the release of the pro-inflammatory neutrophil chemotactic factor interleukin-8 (IL-8) and the anti-inflammatory cytokines interleukin-10 (IL-10) and secretory leukocyte protease inhibitor (SLPI). The tissues studied were non-pregnant cervical explants, peripheral blood and the monocyte cell line U937. Seminal plasma fraction (SPF) significantly (P < 0.05) stimulated release of IL-8 and inhibited release of SLPI from non-pregnant cervical explants. SPF, PGE2 and 19-hydroxy PGE significantly (P< 0.005) stimulated IL-8 release from peripheral blood and U937 cells. 19-hydroxy PGE was significantly (P< 0.005) more effective than PGE2 in stimulating IL-8 release. Seminal plasma, SPF and PGE2 significantly (P < 0.05) stimulated IL-10 release from U937 cells. 19-hydroxy PGE stimulated IL-10 release from U937 cells but this failed to reach significance. Release of IL-10 by cervical explants and SLPI by peripheral blood and U937 cells were below the detection limit of the assays employed. We suggest that the anti- and pro-inflammatory immune responses which seminal plasma induces might act in combination initially to promote sperm survival and then to facilitate their removal from the female genital tract.

Evaluation of maternal serum dimeric inhibin A as a first-trimester marker of Down's syndrome.

While second-trimester prenatal screening programmes for Down's syndrome have become established in prenatal care, it would be advantageous to be able to offer screening in earlier pregnancy. To this end, we have evaluated a new potential maternal serum marker, dimeric inhibin A, as a possible first-trimester marker. Dimeric inhibin A was measured in prospectively collected maternal serum from 23 cases of Down's syndrome and matched chromosomally normal controls, at 11-13 weeks' gestation. Levels of this protein were significantly elevated in the Down's pregnancies compared with the control pregnancies. The median multiple of the normal median (MOM) for the Down's samples was 2.46 (95 per cent confidence interval: 2.11-3.26, P < 0.0001 vs. controls). These results suggest that dimeric inhibin A is a useful discriminator of Down's-affected pregnancies from normal pregnancies in the first trimester and that sensitive screening in combination with maternal age and other possible markers may be practicable in the first trimester.