Animals and lipopolysaccharide-induced sepsis model

Male C57BL/6J mice (8–9 weeks old, 25–30 g) were purchased from the National Lab Animal Center (Taiwan). The NOX2 subunit knockout mice B6.129S6-Cybbtm1Din/J mice (gp91^phox−/−, JAX stock 002365) and B6(Cg)-Ncf1<m1J>/J mice (p47^phox−/−, JAX Stock 004742) were obtained from The Jackson Laboratory (Bar Harbor, ME, USA). The PHOX^−/− mutation is maintained on a C57BL/6J background; therefore, C57BL/6J (PHOX^+/+) mice were used as control animals for this study. The animals were housed in a specific pathogen-free room at 21 °C under a 12-h/12-h artificial light/dark cycle with free access to feed. Experiments were performed using age- and weight-matched male animals. All procedures were approved by the Animal Care and Use Committee of Changhua Christian Hospital. The mouse model of sepsis was induced by intraperitoneal (i.p.) injection of 4 mg/kg lipopolysaccharide (LPS), modified from a previous study in mice [28]. In total, 352 of mice were used in this study, including 248 of WT mice, 52 of p47^phox−/− mice, and 52 of gp91^phox−/− mice.