Figure 6.

HMGB1 induces macrophage pyroptosis in mouse endotoxemia model. (a) C57BL/6 mice were injected with LPS (20 mg/kg BW) or normal saline (NS) intraperitoneally (i.p.). AMs were isolated at 18 h after LPS injection and stained with FLICA caspase-1 fluorescent reagent (green), Cell Death Reagent (red), and Hoechst (blue). Images were obtained by confocal microscopy (original magnification × 600). (b) WT or RAGE^−/− mice were injected with LPS or NS i.p. Neutralizing anti-HMGB1 IgY (SHINO-TEST Corporation) or control nonimmune IgY (Fitzgerald, North Acton, MA) in a dose of 2 mg/kg BW was administered to some animals 30 min before LPS i.p. injection. Blood monocytes were collected at 18 h after LPS and stained with Cell Death reagent (TMR red) and FLICA caspase-1 fluorescent reagent (AF488), and double-stained pyroptotic monocytes were detected by flow cytometry. Results are representative of three independent experiments. The graph shows the mean and S.D., n=3. *P<0.05 versus the group labeled with no asterisk