OBJECTIVETo detect the expressions of interleukin-6 (IL-6) and soluble intercellular adhesion molecule-1 (sI- CAM-1) in the seminal plasma of infertile men and explore the role of inflammatory cytokines in male immune infertility.

METHODSBased on the results of the sperm-bound antibody immunobead test, 123 males with clinically suspected infertility were divided into an immune infertility group (n = 41), other infertility group A (n = 37), and other infertility group B (n = 45). The immune infertility patients were further subdivided into a leukocyte-positive and a leukocyte-negative group according to the results of leukocyte peroxidase staining. The control group included 31 males confirmed to be fertilein the clinic. Statistical analyses were conducted on the differences in inflammatory cytokines expressions and main parameters in the seminal plasma among different groups. The seminal liquefaction time was measured by visual and microscopic observation, sperm concentration and motility detected using the computer-assisted sperm analysis system, sperm viability determined by hypotonic swelling assay, and the expression levels of IL-6 and sICAM-1 meas- ured by ELISA.

RESULTSThe infertility groups showed significantly lowers perm viability (P < 0.05) and progressive motility (P < 0.01) than the fertile control, but no remarkable differences from the latter in sperm concentration (P > 0.05) and semen liquefaction time (P > 0.05). No statistically significant differences were observed in seminal parameters between the immune infertility group and other infertility groups (P > 0.05). The IL-6 and sICAM-1 levels in the seminal plasma were extremely significantly higher in the im- mune infertility group ([37.92 ± 17.01] ng/L and [89.15 ± 41.82] ng/ml), other infertility group A ([22.23 ± 13.77] ng/L and [67.81 ± 33.24] ng/ml), and other infertility group B ([18.75 ± 14.32] ng/L and [53.25 ± 27.09] ng/ml) than in the normal control group ([9.47 ± 5.76] ng/L and [19.46 ± 9.77] ng/ml) (P <0.01) , with remarkable differences between the immune infertility group and the other two infertility groups (P < 0.05). The leukocyte-positive patients showed significantly increased levels of IL-6 ([49.25 ± 21.46] ng/L) and sICAM-1 ([104.36 ± 46.41] ng/ml) as compared with the leukocyte-negative ones ([31.38 ± 15.54] ng/Land [80.38 ± 35.52] ng/ml) (both P < 0.05).

CONCLUSIONIL-6 and sICAM-1 in the seminalplasma are involved in male immune infertility.