Involvement of Serum and Lipopolysaccharide in the Production of Interleukin‐1‐ and Interleukin‐6‐like Molecules by Human Sperm Cells

PROBLEM: To examine the capacity of sperm cells from fertile and infertile men to secrete interleukin (IL)‐6, and the involvement of serum factors and lipopolysaccharide (LPS) in the regulation of IL‐6 and IL‐1 production by sperm cells. METHODS: Swim‐up sperm cells from fertile (donors) and oligoteratoasthenospermic (OTA)‐infertile men were incubated with or without 5% fetal calf serum (FCS) and LPS (10 μg/mL) for 2–24 hr. After incubation, IL‐6 and IL‐1 bioactivities were measured in supernatants and lysates by specific bioassays (B9 cell proliferation assay and 1A‐5 system, respectively). RESULTS: IL‐6‐ and IL‐1‐like activities were observed to be produced by swim‐up sperm cells from both study groups. Stimulation of swim‐up sperm cells with either LPS or FCS or both together did not affect their capacity to produce IL‐1. However, LPS, but not serum increased the secretion levels of IL‐6 by swim‐up sperm cells. CONCLUSIONS: Swim‐up sperm cells from both study groups constitutively produce IL‐6 and IL‐1, and serum components did not affect this capacity. However, LPS was shown to increase the capacity of swim‐up sperm cells of both study groups to secrete IL‐6, but not IL‐1. Cytokines may be involved in the physiology and pathophysiology of sperm functions and, thus, may affect male fertility.