Human IL-36 beta/IL-1F8 Antibody

Human interleukin 1 family member #8 [IL-1F8; also named Interleukin-36 beta, IL36B, FIL-1 eta (eta) and IL-1H2] is a member of the IL-1 family of proteins (1‑3). IL-1 family members include IL‑1 beta, IL-1 alpha, IL-1ra, IL-18 and IL-1F5 through F10 (4). All family members show a 12 beta-stranded beta-trefoil configuration, and are believed to have arisen from a common ancestral gene that has undergone multiple duplications (4). Two alternatively spliced transcript variants encode distinct (164 or 157 residues) protein isoforms that differ in their C-terminal 70 amino acid (aa) residues have been reported (3). IL-1F8 isoform 2 is synthesized as a 157 aa protein that contains no signal sequence and no prosegment (1, 2). Unlike IL-1F8 isoform 1 which lacks potential N‑linked glycosylation sites, isoform 2 contains one potential N-linked glycosylation site in its unique C-terminus. IL-1F8 is reported to be actively secreted (1). Human IL-1F8 isoform 2 shares 61% aa identity with mouse IL-1 ra, a 183 aa form of IL‑1F8. Within the IL-1 family, IL-1F8 shares 30%, 32%, 37%, 46%, 34%, 45% and 28% aa sequence identity with IL-1 ra, IL-1 beta, IL-1F5, F6, F7, F9 and F10, respectively. Cells reported to express IL-1F8 include resting and activated monocytes and B cells (1, 4). The receptor for IL-1F8 is reported to be a combination of IL-1 Rrp2 and IL-1 RAcP (5). Recombinant IL-1F8, along with IL-1F6 and IL-1F9, has been shown to activate the pathway involving NF-kappa B and MAPK in an IL-1 Rrp2 dependent manner.