Cytokine expression in the seminal plasma and its effects on fertilisation rates in an IVF cycle.

Cytokines are released by various immunocompetent cell subsets in the male urogenital tract and are thought to affect sperm cell function and reproductive process. The aim of the study was to evaluate the levels and a possible role of seven seminal plasma cytokines with fertilisation rates in men attending an in vitro fertilisation (IVF) programme. A total of 36 men of couples who were undergoing traditional IVF in a regional reproductive medicine unit were recruited into this prospective study. Cytokines such as interleukin (IL)-6, IL-8, IL-10, IL-11, IL-12, tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) in the seminal plasma were determined using enzyme linked immunosorbent assay. IL-6, IL-8, IL-10, IL-11 and IFN-γ were detected in all samples. IL-12, and TNF-α were detected in most samples. Levels of IL-11 were significantly higher in the good fertiliser group (P ≤ 0.05). Positive correlation between cytokines such as IL-6 and IL-8 (P < 0.03), IL-10 and IL-11 (P < 0.001) and IFN-γ and IL-10 and IL-11 (P < 0.04 and P < 0.0001 respectively) were found. Our study confirms that the six cytokines other than IL-11 do not affect spermatozoon-oocyte interaction and fertilisation rates in IVF. IL-11 could have a role in the fertilising capacity of the spermatozoa. Significant correlation exists among these cytokines which shows that cytokines rarely act in isolation but rather in a network.

The role of cytokine expression in different subgroups of subfertile men.

PROBLEM: 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. METHOD OF STUDY: 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). RESULTS: 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. CONCLUSION: 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.