Interleukin 17F is a disulfide-linked homodimeric protein belonging to the IL17 family of proinflammatory cytokines. Members belonging to this family share conserved features of cysteine-knot structures but differ in their N-terminal regions. The T-helper cell produced IL17 family is inducible by IL15 and IL23, and IL17F induces T-cell and PBMC activation and proliferation. It also performs cartilage matrix turnover and angiogenesis prevention. IL17F is the most homologous to IL17 in the IL17 family and dimerizes in a way similar to that of nerve growth factors (NGF) and other neurotrophins. Recombinant Human IL17F expressed in human 293 cells is a homodimeric glycoprotein with a molecular mass of 38 kDa.