Role of genitourinary inflammation in infertility: synergistic effect of lipopolysaccharide and interferon-gamma on human spermatozoa

Pro-inflammatory cytokines are elevated in the semen of patients with genit ourinary inflammation (GUI). Whether this increase in cytokines in GUI pati ents plays any critical role in male factor infertility is not clear. The p resent study investigated the in vitro effects of two important pro-inflamm atory cytokines, lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma), on sperm motility, viability, membrane integrity and motion parameters. Wa shed spermatozoa from healthy donors were incubated with LPS (0.1 mg/mL) or IFN-gamma (0.1 mg/mL) alone or in combination. Sperm motility, viability, membrane integrity and computer-assisted motion were evaluated at various t ime intervals (0, 30, 60 and 180 min) after treatment. Sperm membrane integ rity was analysed using the hypoosmotic swelling test (HOST). LPS and IFN-g amma individually did not alter sperm viability or motility, but their comb ination showed a significant time-dependent decrease (p < 0.05) in sperm mo tility, viability and membrane integrity. Sperm motion parameters (straight -line velocity, curvilinear velocity, mean linearity, or amplitude of later al head displacement) were not affected by LPS or IFN-<gamma> at the concen trations used in this study. These data suggest that the combination of LPS and IFN-gamma is detrimental to human spermatozoa and may contribute to ma le factor infertility in patients with chronic GUI.