HUMAN SEMEN INDUCES INTERLEUKIN-10 AND 70 KDA HEAT-SHOCK-PROTEIN GENE-TRANSCRIPTION AND INHIBITS INTERFERON-GAMMA MESSENGER-RNA PRODUCTION IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS

The influence of semen on immunity in sexually active women has been s carcely studied. The effect of human semen on production of messenger RNA (mRNA) for the anti-inflammatory TH2-related cytokine, interleukin -10 (IL-10), the 70 kDa heat shock protein (HSP70) and the pro-inflamm atory TH1-related cytokine, interferon-gamma (IFN-gamma) was examined. Co-incubation of peripheral blood mononuclear cells (PBMC) from 10 wo men with a non-cytotoxic 1:50 dilution of semen lead to induction of I L-10 mRNA. Semen from each of seven different men tested induced IL-10 mRNA in PBMC. IL-10 protein was also released into the culture supern atant after PBMC-semen co-culture. Similarly, semen induced transcript ion of the HSP70 gene in PBMC obtained from 10 women. In contrast, sem en did not induce IFN-gamma mRNA in any of the female PBMC donors. Fur thermore, semen markedly inhibited IFN-gamma mRNA production without a ffecting cell viability in PBMC that were cocultured with phytohaemagg lutinin, a potent IFN-gamma-inducing T-cell mitogen. Thus, human semen is both an inducer of an anti-inflammatory (TH2) immune response and an inhibitor of pro-inflammatory (TH1) cell-mediated immunity.