title: Role of interleukin-17F in asthma.
abstract: A new family of cytokines, the interleukin (IL)-17 family, has recently been defined, which reveals unique functions and distinct ligand-receptor signaling systems. This family contains six members, IL-17 (also called IL-17A), IL17B, IL-17C, IL-17D, IL-17E (IL-25) and IL-17F. The IL-17F gene was discovered in 2001, and is located on chromosome 6p12. Notably, among this family, IL-17F has been well characterized both in vitro and in vivo, and has been shown to have a pro-inflammatory role in asthma. IL-17F is clearly expressed in the airway of asthmatics and its expression level is correlated with disease severity. Moreover, a coding region variant (H161R) of the IL-17F gene is inversely associated with asthma and encodes an antagonist for the wild-type IL-17F. IL-17F is able to induce several cytokines, chemokines and adhesion molecules in bronchial epithelial cells, vein endothelial cells, fibroblasts and eosinophils. IL-17F utilizes IL-17RA and IL-17RC as its receptors, and activates the MAP kinase related pathway. IL-17F is derived from several cell types such as Th17 cells, mast cells and basophils, and shows a wide tissue expression pattern including lung. Overexpression of IL-17F gene in the airway of mice is associated with airway neutrophilia, the induction of many cytokines, an increase in airway hyperreactivity, and mucus hypersecretion. Hence, IL-17F may have a crucial role in allergic airway inflammation, and have important therapeutic implications in asthma.
authors.affiliation: Department of Respiratory Medicine, Institute of Clinical Medicine, University of Tsukuba, Ibaraki 3058575, Japan. mkawaguchi@md.tsukuba.ac.jp
authors.forename: Mio
authors.initials: M
authors.lastname: Kawaguchi
authors.forename: Fumio
authors.initials: F
authors.lastname: Kokubu
authors.forename: Junichi
authors.initials: J
authors.lastname: Fujita
authors.forename: Shau-Ku
authors.initials: SK
authors.lastname: Huang
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hizawa
mesh_terms: D000818:Animals; D001249:Asthma / Q000235:genetics / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism*; D006801:Humans; D020381:Interleukin-17 / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D011110:Polymorphism, Genetic; D018121:Receptors, Cytokine / Q000378:metabolism*; D015398:Signal Transduction / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D016207:Cytokines; D020381:Interleukin-17; D018121:Receptors, Cytokine