IFN-gamma alters the human sperm membrane permeability to Ca2+

AbstractInflammation in the male genitourinary tract has been associated with the release of pro-inflammatory cytokines such as interferon-gamma (IFN-γ) and elevated reactive oxygen species, which affects spermatozoa capacitation, motility, and the acrosome reaction, along with functions regulated by the concentration of cytoplasmic Ca2+ ([Ca2+]cyto). Though Ca2+ signaling is of particular significance in sperm, the effect of IFN-γ intracellular calcium on these cells is still unknown. The present study evaluated the effect of IFN-γ on the [Ca2+]cyto and Ca2+ permeability on human sperm. A cell suspension loaded with fura-2 was incubated with or without IFN-γ (from 0 to 2000 pg/ml) for 0, 30, 60, and 120 minutes, and the [Ca2+]cyto was measured. The permeability to Ca2+ was evaluated by the change of the intracellular concentration following an extracellular Ca2+ pulse. IFN-γ at low concentrations (≤500 pg/ml) did not affect the [Ca2+]cyto and Ca2+ permeability of sperm. At a high concentration (2000 pg/m...