Recombinant Mouse IL-17RB Fc Chimera Protein, CF

The interleukin 17 (IL-17) family of cytokines, comprising six members (IL-17, IL-17B through IL17F), are structurally related proteins with a conserved cysteine-knot structure. These proinflammatory cytokines can induce local cytokine production and are involved in the regulation of the immune response. The cognate receptors activated by some of these cytokines have been identified (1, 2).

Interleukin-17B Receptor (IL-17B R), also known as IL-17 Rh1, IL-17E R and EVI27, represents the second receptor of the IL-17 family cytokines to be recognized (2-4). Mouse IL17B R cDNA encodes a 499 amino acid (aa) residue type I membrane protein with a putative 17 aa signal peptide, a 269 aa extracellular domain, a 21 aa transmembrane domain and a 192 aa cytoplasmic tail. As a result of alternative splicing, a secreted variant of IL-17B R also exists (4). Human and mouse IL-17B R share 76% aa sequence identity. The IL-17B R protein sequence is only 19.2% and 18.2% identical to the human and mouse IL-17 R sequence, respectively. However, the receptors share many conserved cysteine residues within their extracellular domains as well as additional conserved elements within their cytoplasmic domains. At least three additional type I transmembrane receptors with homology to IL-17 R, including IL-17 RL (IL-17 RC), IL-17 RD, and IL-17 RE, have been reported (2, 6). By Northern blot analysis, mouse IL-17B R is highly expressed in liver and testes and is expressed at lower levels in kidney and lung. It is also expressed in some hematopoietic cell lines, including selected T cell, B cell, and myeloid cell lines (2 - 4). The expression of IL-17B R is significantly up-regulated under inflammatory conditions (7). IL-17 RB binds strongly to IL-17E and weakly to IL-17B. It does not bind IL-17 or IL-17F. Activation of IL-17B R by its ligands results in the activation of nuclear factor kappa-B (2-4).