Consistent with these results, our analysis of both ex vivo-stimulated mutant macrophages and in vivo CAPS and endotoxemia models unequivocally established that MCC950/CRID3 potently inhibits inflammasome activation by wild-type Nlrp3 but not the FCAS-associated Nlrp3L351P mutant. Here, NLRP3 is linked to serum lipopolysaccharide activity.