Interleukin-17AF (IL-17AF) is a member of the IL-17 family of Proteins produced by a subset of T cells, called Th17, following stimulation with IL-23. Since IL-17AF is thought to signal through the IL-17RA receptor, its biological function is similar to that of IL-17A in that it induces the production of a variety of chemokines, in addition to airway neutrophilia. In regard to these functions, IL-17AF has less activity than the IL-17A homodimer but, greater activity than the IL-17F homodimer. and IL-17AF both show activity on cells. Recombinant IL-17AF is a nonglycosylated heterodimer, containing one IL-17A subunit and one IL-17F subunit. The dimer has a total of 271 amino acids, with an approximate molecular weight of 30.7 kDa.