Regulator of procaspase-1/CASP1 activation implicated in the regulation of the proteolytic maturation of pro-IL-1beta/IL1B and its release during inflammation. Inhibits the release of IL1B in response to LPS in monocytes. However, unlike CASP1, do not induce NF-kappa-B activation. Interacts with pro-CASP1. Ubiquitous. By IFNG/IFN-gamma in monocytic cell lines.