Plasma sE-cadherin and the plasma sE-cadherin/sVE-cadherin ratio are potential biomarkers for chronic obstructive pulmonary disease

Background: Chronic obstructive pulmonary disease (COPD) is characterized by airway inflammation with endothelial dysfunction. Cadherins are adhesion molecules on epithelial (E-) and vascular endothelial (VE-) cells. Soluble (s) cadherin is released from the cell surface by the effects of proteases including matrix metalloproteinases (MMPs). Objective: The aim of this study was to examine the associations of sE-/sVE-cadherin levels in plasma with the development of COPD. Methods: Plasma sE-/VE-cadherin levels were measured by an enzyme-linked immunosorbent assay in 115 patients with COPD, 36 symptomatic smokers (SS), 63 healthy smokers (HS) and 78 healthy non-smokers (HN). sE-cadherin and MMP-7 levels in epithelial lining fluid (ELF) were measured in 24 patients (12 COPD and 12 control). Results: Plasma sE-cadherin levels and sE-cadherin/sVE-cadherin ratios were significantly higher in COPD and SS than in HS and HN groups, while plasma sVE-cadherin levels were lower in COPD than in HS and HN groups (p < 0.0001). sE-cadherin levels paralleled the severity of airflow limitation in both plasma (p < 0.01) and ELF (p < 0.05), while plasma sVE-cadherin levels were inversely correlated with the extent of emphysema (p < 0.05). MMP-7 levels were correlated with sE-cadherin levels in ELF. Conclusions: Plasma sE-cadherin levels and sE-cadherin/sVE-cadherin ratios are potential biomarkers for COPD.