The role of cytokine expression in different subgroups of subfertile men

The aim of this study was to evaluate the levels of seminal plasma cytokines interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), interleukin 11 (IL-11), interleukin 12 (IL-12), tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) in male subfertility.

A total of 73 male partners of an infertile couple attending a regional andrology unit were recruited into this prospective study and subdivided into the various groups based on semen analysis. Concentrations of cytokines such as IL-6, IL-8, IL-10, IL-11, IL-12, TNF-alpha and IFN-gamma in the seminal plasma were determined using enzyme linked immunosorbent assay (ELISA).

Significant higher concentrations (P < 0.05) of IL-6 in the mild and severe oligospermic group, IL-8 and IL-10 in the asthenospermic group and IL-6, IL-10, TNF-alpha and IFN-gamma in the obstructed azoospermic group were determined. IL-10 concentrations correlated significantly with other cytokines in the obstructed azoospermic group and the asthenospermic group.

Our study confirms that cytokines rarely act in isolation, but rather in a network of other cytokines and may affect sperm function directly or indirectly. The presence of increased levels of cytokines in the obstructed azoospermic group suggests that the cytokines may not originate from the testis.