Human IL36RN (IL1F5) is one of the cytokines from the interleukin 1 family encoded by a cluster of genes on chromosome 2. All members of this family show a 12 beta -strand, beta -trefoil configuration. IL36RN is a secreted protein monomer which is also known as interleukin 36 receptor antagonist (IL36RA). This cytokine is predominantly expressed in keratinocytes and a variety of other cell types including brain leukocytes, dendritic cells and macrophage cell types. IL36RN has shown increased expression in lesional psoriasis skin and is thought to play a role in skin inflammation. IL1F5 is a specific antagonist of the IL1 receptor related protein 2 - mediated response to IL1F9. It is also known to specifically inhibit the activation of NF-Kappa-B transcription factor which is induced by IL1F6.