IL-17B is a disulfide-linked homodimer of two 161 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-17B is expressed by T-cells and has been shown to stimulate release of TNF-α and IL-1β from cells of the monocyte lineage. Recombinant human IL-17B is a 36.6 kDa non-disulfide-linked homodimer of two 161 amino acid polypeptide chains.