Abstract
The gender difference in tumor necrosis factor-α (TNF-α) production in human neutrophils stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ) was explored by using peripheral blood neutrophils from young men and women. As compared with female neutrophils, male neutrophils released greater amounts of TNF-α, and exhibited stronger activation of mitogen-activated protein kinases and phosphatidylinositol 3-kinase in response to LPS stimulation. LPS-induced TNF-α production was markedly enhanced by pretreatment of cells with IFN-γ, and IFN-γ-mediated priming in male neutrophils was significantly greater than that in female neutrophils. Male neutrophils showed higher expression of TLR4, but not IFN-γ receptors, than female neutrophils, and its expression was increased by stimulation with IFN-γ or IFN-γ plus LPS. These findings indicate that male neutrophils show higher responsiveness to stimulation with LPS and IFN-γ than female neutrophils, and suggest that the gender difference in neutrophil responsiveness to LPS and IFN-γ is partly responsible for that in the outcome of sepsis, in which premenopausal women show a favorable prognosis as compared with men.