CARD18 belongs to the death-domain-fold superfamily which is induced by proinflammatory stimuli. CARD18 contains basically only a Caspase recruitment domain, inhibits generation of IL-1b by cooperating with caspase-1 and inhibiting connotation with RIP 2. The connotation of CARD18 to caspase-1 is enabled by the charge-charge interactions between the prodomain of caspase-1 and the surface charge of CARD18.