IL-36 gamma, formerly known as IL-1F9, IL-1 epsilon, or IL-1H1, is part of the IL-1 family, which includes IL-1 beta, IL-1 alpha, IL-1ra, IL-18, and others. All family members share a 12 beta-strand, beta-trefoil structure. Mouse IL-36 gamma is a 18-22 kDa, 164 amino acid protein produced by Langerhans cells, keratinocytes, and stomach cells, acting as a first-line defense against pathogens. Its expression is induced by various stimuli and is elevated in skin conditions like psoriasis, lung disorders, and viral infections. IL-36 gamma's receptor is a combination of IL-1 Rrp2 and IL-1 RAcP, activating NF-kappa B and MAPK pathways. It induces production of inflammatory cytokines and chemokines. Recombinant IL-36 proteins are less active than their endogenous counterparts, but N-terminal trimming enhances activity.