A novel heterodimeric cytokine consisting of IL-17 and IL-17F regulates inflammatory responses

Cell Res. 2007 May;17(5):435-40. doi: 10.1038/cr.2007.35.


CD4+ helper T (TH) cells play crucial roles in immune responses. Recently a novel subset of TH cells, termed TH(IL-17), TH17 or inflammatory TH (THi), has been identified as critical mediators of tissue inflammation. These cells produce IL-17 (also called IL-17A) and IL-17F, two most homologous cytokines sharing similar regulations. Here we report that when overexpressed in 293T cells, IL-17 and IL-17F form not only homodimers but also heterodimers, which we name as IL-17A/F. Fully differentiated mouse THi cells also naturally secrete IL-17A/F as well as IL-17 and IL-17F homodimeric cytokines. Recombinant IL-17A/F protein exhibits intermediate levels of potency in inducing IL-6 and KC (CXCL1) as compared to homodimeric cytokines. IL-17A/F regulation of IL-6 and KC expression is dependent on IL-17RA and TRAF6. Thus, IL-17A/F cytokine represents another mechanism whereby T cells regulate inflammatory responses and may serve as a novel target for treating various immune-mediated diseases.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • Cells, Cultured
  • Dimerization
  • Humans
  • Inflammation / physiopathology
  • Interleukin-17 / chemistry
  • Interleukin-17 / metabolism*
  • Mice
  • Recombinant Fusion Proteins / metabolism


  • Il17a protein, mouse
  • Il17f protein, mouse
  • Interleukin-17
  • Recombinant Fusion Proteins