Figure 2.

NLRP3 is required for inflammasome activation by ultrasmall nanoparticles. (A,B) ELISA test for the induction of IL-1β production in supernatants (A) and immunoblot analysis of whole cell lysates (B) of bone marrow derived dendritic cells (BMDCs) primed with LPS (100 ng/mL, 3 h) alone or followed by 6 h of Au4.5, Au13, Au30, or Au70 (50, 100, 200 μg/mL) treatment or 1 h of ATP (5 mM) treatment. Whole cell lysates were immunoblotted with indicated antibodies (B). (C,D) BMDCs from wild-type, Nlrp3^−/−, Aim2^−/−, and Caspase-1^−/− mice were primed with LPS (100 ng/mL, 3h) and then treated with Au4.5 nanoparticles at 200 μg/mL for 6 h or ATP for 1 h. Immunoblot analysis of cell lysates of pro-Caspase-1 and cleaved Caspase-1 p10 are shown in (C). Production of IL-1β in the supernatants was analyzed by ELISA (D). (E) ELISA for IL-1β production in cell supernatants of 293CIA cells transfected with plasmids encoding HA-NLRP3, Flag-Aim2, or Flag-NLRC4, respectively, followed by treatment with Au4.5 (200 μg/mL) or nigericin (1 μM) for 6 h or transfection with poly dA:dT for 6 h. *p < 0.05, **p < 0.01; NS, not significant. Data are representative of three experiments (mean ± SD).