Modulation of bronchial epithelial cells by IL-17

J Allergy Clin Immunol. 2001 Nov;108(5):804-9. doi: 10.1067/mai.2001.119027.


Background: The induction of epithelial cytokines/chemokines is crucial in the migration of leukocytes, and its regulatory mechanisms remain incompletely defined.

Objective: To determine the role of IL-17, a CD4(+) T cell-derived cytokine, in modulation of primary bronchial epithelial cells, the expression of IL-6, IL-8, and intercellular adhesion molecule 1 (ICAM-1) and the potential involvement of mitogen-activated protein (MAP) kinases in IL-17-mediated signaling were examined.

Methods: The levels of gene expression and protein production for IL-6 and IL-8 in IL-17-treated cells, in the presence or absence of MAP kinase inhibitors, were analyzed by RT-PCR and ELISA, respectively, and activation of MAP kinases was determined by Western blot analyses.

Results: We showed first that IL-17 induced time-dependent expression of IL-6 and IL-8 but not of the chemokines eotaxin and RANTES. In addition, IL-17 induced activation of extracellular signal-regulated kinase 1/2 but not of p38 or JNK kinases. A selective MAP kinase kinase inhibitor, PD98059, inhibited IL-17-induced IL-6 and IL-8. A combination of IL-17 and each of the cytokines IL-4, IL-13, and IFN-gamma further enhanced IL-8 expression. IL-17 alone did not induce ICAM-1 expression and showed no effect on IL-4- or IL-13-induced ICAM-1 expression. In contrast, a combination of IL-17 and IFN-gamma augmented IL-6 and ICAM-1 expression.

Conclusion: These findings suggest that IL-17, alone or in combination with other cytokines, modulates airway inflammation via-in part-the expression of epithelial IL-6, IL-8, and ICAM-1.

MeSH terms

  • Bronchi / cytology*
  • Cells, Cultured
  • Cytokines / pharmacology
  • Drug Synergism
  • Epithelial Cells / drug effects
  • Epithelial Cells / immunology
  • Flavonoids / pharmacology
  • Humans
  • Intercellular Adhesion Molecule-1 / biosynthesis
  • Interleukin-17 / pharmacology*
  • Interleukin-6 / biosynthesis
  • Interleukin-6 / genetics
  • Interleukin-8 / biosynthesis
  • Interleukin-8 / genetics
  • Kinetics
  • MAP Kinase Signaling System
  • Mitogen-Activated Protein Kinase 1 / antagonists & inhibitors
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / metabolism
  • RNA, Messenger / biosynthesis
  • Respiratory Mucosa / drug effects
  • Respiratory Mucosa / immunology*


  • Cytokines
  • Flavonoids
  • Interleukin-17
  • Interleukin-6
  • Interleukin-8
  • RNA, Messenger
  • Intercellular Adhesion Molecule-1
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one