Soluble Fas and interleukin-6 and interleukin-8 levels in seminal plasma of infertile men

The seminal plasma levels of soluble Fas (sFas) and interleukins IL-6 and IL-8 were measured and their relationship with semen qualities was examined. The seminal plasma sFas level in fertile males was significantly higher than that in the infertile group. On the other hand, seminal plasma level of IL-6 was significantly lower in fertile males than in the infertile group. In the infertile group, patients with oligozoospermia had a lower seminal plasma sFas and a higher IL-6 level than those with normal sperm concentration. There was an inverse correlation between IL-6 and sperm concentration in infertile patients. Seminal plasma IL-8 was not correlated with sperm parameters. It would appear that certain kinds of cytokine in the seminal plasma might play an important role in improving semen quality.