Interleukin-13 and its receptors in idiopathic interstitial pneumonia: clinical implications for lung function

J Korean Med Sci. 2009 Aug;24(4):614-20. doi: 10.3346/jkms.2009.24.4.614. Epub 2009 Jul 29.

Abstract

Idiopathic interstitial pneumonia (IIP) is characterized by varying degrees of interstitial fibrosis. IL-13 and IL-4 are strong inducers of tissue fibrosis, whereas IFN-gamma has antifibrotic potential. However, the roles of these substances in IIP remain unknown. IL-13, IL-4, and IFN-gamma were measured in the BAL fluid of 16 idiopathic pulmonary fibrosis (IPF) patients, 10 nonspecific interstitial pneumonia (NSIP) patients, and 8 normal controls. The expression of IL-13 and IL-13Ralpha1/alpha2 in lung tissues was analyzed using ELISA and immunohistochemistry. IL-13 levels were significantly higher in IPF patients than the others (P<0.05). IL-4 levels were higher in both IPF and NSIP patients than in normal controls (P<0.05), and IFN-gamma levels were lower in NSIP patients than in normal controls (P=0.047). IL-13 levels correlated inversely with FVC% (r=-0.47, P=0.043) and DLCO% (r=-0.58, P=0.014) in IPF and NSIP patients. IL-13 was strongly expressed in the smooth muscle, bronchial epithelium, alveolar macrophages and endothelium of IPF patients. IL-13Ralpha1, rather than IL-13Ralpha2, was strongly expressed in the smooth muscle, bronchial epithelium, and endothelium of IPF patients. IL-13 and its receptors may contribute to the pathogenesis of fibrosis in IIP and appear to be related to the severity of the disease.

Keywords: Idiopathic Pulmonary Fibrosis; Interleukin-13; Interleukin-13 Receptor Alpha1 Subunit; Interleukin-13 Receptor Alpha2 Subunit; Lung Function; NSIP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Female
  • Humans
  • Idiopathic Interstitial Pneumonias / diagnosis
  • Idiopathic Interstitial Pneumonias / metabolism*
  • Idiopathic Pulmonary Fibrosis / diagnosis
  • Idiopathic Pulmonary Fibrosis / metabolism*
  • Interferon-gamma / analysis
  • Interleukin-13 / analysis*
  • Interleukin-13 Receptor alpha1 Subunit / metabolism*
  • Interleukin-13 Receptor alpha2 Subunit / metabolism*
  • Interleukin-4 / analysis
  • Lung / physiopathology
  • Male
  • Middle Aged

Substances

  • Interleukin-13
  • Interleukin-13 Receptor alpha1 Subunit
  • Interleukin-13 Receptor alpha2 Subunit
  • Interleukin-4
  • Interferon-gamma