Enhanced levels of colony stimulating factor-1 (CSF-1) in sera and seminal plasma of antisperm antibody-positive infertile men

This investigation was carried out to examine the levels of CSF-1 in sera and seminal plasma of fertile, immunoinfertile, and male factor-infertile men in order to study the role of CSF-1 in human infertility. Sera, sperm, and seminal plasma were analyzed for antisperm antibodies by the sperm immobilization technique, tray agglutination technique, and immunobead binding technique. Sperm motility and fertilizing capacity were analyzed by sperm motion analysis and sperm penetration assay, respectively. CSF-1 concentration was estimated by the competitive radioimmunoassay. CSF-1 was detected in sera of both fertile and immunoinfertile men (mean ± SD; fertile men: 52.9 ± 10.3 pg/mg protein; immunoinfertile: 58.2 ± 19.5 pg/mg proteinic p ±05). CSF-1 was also detected in the seminal plasma of fertile, immunoinfertile, and male factor-infertile men (mean ± SD; normal fertile men: 1.7 ± 3.5 ng/mg; immunoinfertile men: 10.9 ± 15.6 ng/mg; male factor-infertile men: 0.85 ± 0.25 ng/mg). The levels of CSF-1 were highest in the immunoinfertile men, followed by those in fertile and male factor-infertile men. The average level in immunoinfertile men was significantly different from the average level in fertile or male factor-infertile men (p < 0001). Interestingly, the concentrations of CSF-1 per milliliter of seminal plasma was in general approximately 5 times greater than those in serum. These findings indicate that elevated seminal plasma CSF-1 concentration is correlated with male infertility.