Extracellular matrix (ECM) composition has an important role in determining airway structure. We postulated that ECM lung composition of
chronic obstructive pulmonary disease (
COPD) patients differs from that observed in smoking and nonsmoking subjects without airflow obstruction. We determined the fractional areas of elastic fibres, type-I, -III and -IV
collagen,
versican,
decorin,
biglycan,
lumican,
fibronectin and
tenascin in different compartments of the large and small airways and lung parenchyma in 26
COPD patients, 26 smokers without
COPD and 16 nonsmoking control subjects. The fractional area of elastic fibres was higher in non-obstructed smokers than in
COPD and nonsmoking controls, in all lung compartments.
Type-I collagen fractional area was lower in the large and small airways of
COPD patients and in the small airways of non-obstructed smokers than in nonsmokers. Compared with nonsmokers,
COPD patients had lower
versican fractional area in the parenchyma, higher
fibronectin fractional area in small airways and higher
tenascin fractional area in large and small airways compartments. In
COPD patients, significant correlations were found between elastic fibres and
fibronectin and lung function parameters. Alterations of the major ECM components are widespread in all lung compartments of patients with
COPD and may contribute to persistent airflow obstruction.