IL-17E is a disulfide-linked homodimer of two 145 amino acid polypeptide chains. It belongs to the IL-17 family of structurally-related cytokines that share a highly conserved C-terminal region, but differ from one another in their N-terminal regions and in their distinct biological roles. The six known members of this family, IL-17A through IL-17F, are secreted as homodimers. IL-17E stimulated secretion of IL-8, and induces activation of the transcription factor NF-?B in cells that express the IL-17BR receptor. Recombinant human IL-17E is a 33.8 kDa disulfide-linked homodimer of two 146 amino acid polypeptide chains.