Recombinant Mouse IL-36 beta/IL-1F8 Protein

Mouse interleukin‑36 beta [IL‑36 beta; previously IL‑1F8 and also named FIL‑1 eta (eta) and IL‑1H2] is a member of the IL‑1 family of proteins (1 ‑ 3, 6). IL‑1 family members include IL‑1 beta, IL‑1 alpha, IL‑1ra, IL‑18, IL‑36Ra/IL‑1F5, IL‑36 alpha/IL‑1F6, IL‑37/IL‑1F7, IL‑36 gamma/IL‑1F9 and IL‑1F10 (4, 6). 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). Although two alternatively spliced transcript variants for human IL‑36 beta/IL‑1F8 have been described, to date, only one mouse IL‑36 beta/IL‑1F8 isoform is known (3). Mouse IL‑36 beta/IL‑1F8 is synthesized as a 183 amino acid (aa) protein that contains no signal sequence, no prosegment and no potential N‑linked glycosylation site(s) (1, 2). It is likely that mouse IL‑36 beta/IL‑1F8, similarly to its human homologue, is actively secreted (1). Mouse IL‑36 beta/IL‑1F8 shares 61% and 74% aa identity with human IL‑36 beta/IL‑1F8 isoform 2 and rat IL‑1F8, respectively. Within the IL‑1 family, IL‑36 beta/IL‑1F8 shares 27% sequence with 33%, 32%, 35%, 39% and 28% aa sequence identity with IL‑1ra, IL‑1 beta, IL‑36Ra/IL‑1F5, IL‑36 alpha/IL‑1F6, IL‑36 gamma/IL‑1F9 and IL‑1F10, respectively. Cells reported to express IL‑36 beta/IL‑1F8 include resting and activated monocytes and B cells (1, 4). The receptor for IL‑36 beta/IL‑1F8 is reported to be a combination of IL‑1 Rrp2 and IL‑1 RAcP (5). Recombinant IL‑36 beta/IL‑1F8, along with IL‑36 alpha/IL‑1F6 and IL‑36 gamma/IL‑1F9, has been shown to activate the pathway involving NF‑ kappaB and MAPK in an IL‑1 Rrp2 dependent manner.