Fig. 4.

Specific activation of caspase-7 by NLR inflammasomes. A–C, macrophages from wild type, ASC^−/−, Ipaf^−/−, and Cryopyrin^−/− mice were stimulated with LPS for 3 h and then pulsed with ATP for 30 min, stimulated with LPS alone, pulsed with ATP alone, or infected with wild type S. typhimurium (Salm) or a flagellin-deficient mutant (Salm flib/c−) for 1 h. Extracellular bacteria were washed away, and macrophages were further incubated for 2 h in medium containing gentamycin. Cell extracts were immunoblotted with antibodies against caspase-1 (CASP1) (A), caspase-7 (CASP7) (B), and caspase-3 (CASP3) (C). Black arrows indicate full-length caspases, and white arrows mark the large subunits of activated caspase-1, -3, and -7. Results are representative of at least three independent experiments. CTRL, control; WT, wild type.