Interleukin-17: A new bone acting cytokine in vitro

J Bone Miner Res. 1999 Sep;14(9):1513-21. doi: 10.1359/jbmr.1999.14.9.1513.


Interleukin-17 (IL-17) is a recently cloned cytokine that is exclusively produced by activated T cells, but its receptor has been found on several cells and tissues. Like other proinflammatory cytokines produced by activated T cells, IL-17 may affect osteoclastic resorption and thereby mediate bone destruction accompanying some inflammatory diseases. In the present study, we investigated whether osteogenic cells possess the receptor for IL-17 (IL-17R) and whether IL-17 affects osteoclastic resorption. We found that IL-17R mRNA is expressed both in mouse MC3T3-E1 osteoblastic cells and fetal mouse long bones, suggesting that osteogenic cells may be responsive to IL-17. In fetal mouse long bones, IL-17 had no effect on basal and IL-1beta-stimulated osteoclastic bone resorption, but when given together with tumor necrosis factor-alpha (TNF-alpha) it increased bone resorption dose dependently in serum-free conditions. In addition, IL-17 increased TNF-alpha-induced IL-1alpha, IL-1beta, and IL-6 mRNA expression in fetal mouse metatarsals and IL-1alpha and IL-6 mRNA expression in MC3T3-E1 cells. In conclusion, IL-17R mRNA was expressed by mouse osteoblastic cells and fetal mouse long bones, and IL-17 in combination with TNF-alpha, but not IL-1beta, increased osteoclastic resorption in vitro. IL-17 may therefore affect bone metabolism in pathological conditions characterized by the presence of activated T cells and TNF-alpha production such as rheumatoid arthritis and loosening of bone implants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Resorption
  • Bone and Bones / drug effects
  • Cells, Cultured
  • Interleukin-17 / pharmacology*
  • Mice
  • Osteoblasts / drug effects*
  • Osteoblasts / metabolism
  • RNA, Messenger / analysis
  • Receptors, Interleukin / biosynthesis
  • Receptors, Interleukin / genetics
  • Receptors, Interleukin-17
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / genetics
  • Tumor Necrosis Factor-alpha / pharmacology


  • Il17ra protein, mouse
  • Interleukin-17
  • RNA, Messenger
  • Receptors, Interleukin
  • Receptors, Interleukin-17
  • Recombinant Proteins
  • Tumor Necrosis Factor-alpha