Respiratory Research (Oct 2011)

Evaluation of epithelial mesenchymal transition in patients with chronic obstructive pulmonary disease

  • Wood-Baker Richard,
  • Muller H Konrad,
  • Weston Steven,
  • Ward Chris,
  • Soltani Amir,
  • Reid David,
  • Sohal Sukhwinder S,
  • Walters E Haydn

DOI
https://doi.org/10.1186/1465-9921-12-130
Journal volume & issue
Vol. 12, no. 1
p. 130

Abstract

Read online

Abstract Background The reticular basement membrane (Rbm) in smokers and especially smokers with COPD is fragmented with "clefts" containing cells staining for the collagenase matrix-metalloproteinase-9 (MMP-9) and fibroblast protein, S100A4. These cells are also present in the basal epithelium. Such changes are likely hallmarks of epithelial mesenchymal transition (EMT). We aimed to confirm the epithelial origin of these Rbm cells, and to exclude potential confounding by infiltrating inflammatory cells. Methods Endobronchial biopsy sections from 17 COPD current smokers, with documented Rbm splitting and cellularity were stained for neutrophil elastase (neutrophil marker), CD68 (macrophage/mature fibroblasts), CD4+/CD8+ T lymphocytes, CD19 (B-cells), CD11c (dendritic cells/inflammatory cells), and S100 (Langerhans cells). The number of cells in the Rbm and epithelium staining for these "inflammatory" cell markers were then compared to numbers staining for S100A4, "a documented EMT epitope". Slides were double stained for S100A4 and cytokeratin(s). Results In the basal epithelium significantly more cells stained for S100A4 compared to infiltrating macrophages, fibroblasts or immune cells: median, 26 (21.3 - 37.3) versus 0 (0 - 9.6) per mm, p Conclusions These data provide additional support for active EMT in COPD airways.

Keywords