Unprocessed Interleukin-36? Regulates Psoriasis-Like Skin Inflammation in Cooperation With Interleukin-1.
Ontology highlight
ABSTRACT: Generalized pustular psoriasis is a severe skin disease characterized by epidermal hyperplasia, neutrophil-rich abscesses within the epidermis, and a mixed inflammatory infiltrate in the dermis. The disease may be caused by missense mutations in the IL-36 receptor antagonist, IL-36Ra. Curiously, the related IL-1Ra has therapeutic effects in some of these latter patients. Here, using an experimental mouse model of psoriasiform skin inflammation, we demonstrate in vivo connections between IL-36 and IL-1 expression. After disease initiation, IL-36?-deficient mice exhibited dramatically diminished skin pathology, including absence of epidermal neutrophils, reduced keratinocyte acanthosis, and less dermal edema. In contrast, IL-36? and IL-36? knockout mice developed disease indistinguishable from that of wild-type mice. The endogenous IL-36? was not processed through proteolysis. Although IL-36? expression was strongly induced in an IL-1 signaling-dependent manner during disease, expression of IL-1? was also dependent upon IL-36?. Hence, after being upregulated by IL-1?, IL-36? acts through a feedback mechanism to boost IL-1? levels. Analyses of double knockout mice further revealed that IL-36? and IL-1? cooperate to promote psoriasis-like disease. In conclusion, IL-1? and IL-36? form a self-amplifying inflammatory loop in vivo that in patients with insufficient counter regulatory mechanisms may become hyper-engaged and/or chronic.
SUBMITTER: Milora KA
PROVIDER: S-EPMC4648684 | biostudies-literature | 2015 Dec
REPOSITORIES: biostudies-literature
ACCESS DATA