title: WNT7B in fibroblastic foci of idiopathic pulmonary fibrosis.
abstract: BACKGROUND
  Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial pneumonia causing a loss of respiratory surface area due to a proliferative fibrotic response involving hyperplastic, hypertrophic, and metaplastic epithelium, cystic honeycomb change, septal expansion, and variable inflammation. Wnt (wingless) signaling glycoproteins are known to be involved in lung development and tissue repair, and are up-regulated in patients with IPF. Based on previous qRT-PCR data showing increased Wnt7B in lungs of IPF patients, a systematic, quantitative examination of its tissue site distribution was undertaken.
  
  
  METHODS
  Tissue samples from the Lung Tissue Research Consortium (LTRC) of 39 patients diagnosed with mild to severe IPF/usual interstitial pneumonia (UIP) and 19 normal patients were examined for the immunolocalization of Wnt7B.
  
  
  RESULTS
  In normal lung, moderate Wnt7B reactivity was confined to airway epithelium, smooth muscle of airways and vasculature, and macrophages. IPF lung showed strong Wnt7B reactivity in fibroblastic foci, dysplastic airway and alveolar epithelium, and in highly discrete subepithelial, basement membrane-associated regions. All reactive sites were sized and counted relative to specific microscopic regions. Those in the subepithelial sites were found in significantly greater numbers and larger relative area compared with the others. No reactive sites were present in normal patient controls.
  
  
  CONCLUSIONS
  The results demonstrate Wnt7B to be expressed at high concentrations in regions of active hyperplasia, metaplasia, and fibrotic change in IPF patients. In this context and its previously established biologic activities, Wnt7B would be expected to be of potential importance in the pathogenesis of IPF.
authors: Departments of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA.
authors: Travis
authors: T
authors: Meuten
authors: Ariel
authors: A
authors: Hickey
authors: Katherine
authors: K
authors: Franklin
authors: Brian
authors: B
authors: Grossi
authors: Jeremy
authors: J
authors: Tobias
authors: Donna R
authors: DR
authors: Newman
authors: Samuel H
authors: SH
authors: Jennings
authors: Maria
authors: M
authors: Correa
authors: Philip L
authors: PL
authors: Sannes
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001485:Basement Membrane / Q000473:pathology; D005260:Female; D005347:Fibroblasts / Q000473:pathology*; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000378:metabolism* / Q000473:pathology*; D008264:Macrophages / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000473:pathology; D020545:Respiratory Mucosa / Q000473:pathology; D012137:Respiratory System / Q000098:blood supply / Q000473:pathology; D012720:Severity of Illness Index; D051153:Wnt Proteins / Q000032:analysis / Q000378:metabolism*
chemical_list: C490675:WNT7B protein, human; D051153:Wnt Proteins