ASC, Ipaf and Cryopyrin/Nalp3: bona fide intracellular adapters of the caspase-1 inflammasome

The adapter molecules ASC, Ipaf and Cryopyrin/Nalp3 have each been proposed to regulate caspase-1 within a multi-protein complex called the “inflammasome”. Activation of caspase-1 leads to the cleavage and activation of pro-inflammatory cytokines such as interleukin (IL)-1β and IL-18. The analysis of mice deficient in ASC, Ipaf and Cryopyrin/Nalp3 has revealed that the inflammasome is a dynamic entity that is assembled from different adapters in a stimulus-dependent manner.