Some pathogenic aspects of pulmonary emphysema in COPD patients

Histological and immunohistochemical investigations of lung tissue specimens were performed in 9 patients with COPD underwent lung volume reduction surgery. Lung tissue specimens of died persons without lung and heart pathology were as controls. Tissue expressions of endothelial growth factor (EGF), type 9 matrix metalloproteinase, type 1 matrix metalloproteinase (TIMP-1) tissue inhibitor, and transforming growth factor β1 (TGF β-1) have been studied. Patents with severe emphysema typically had focal interstitial fibrosis, interalveolar septa infiltrated with interstitial macrophages and lymphocytes, hypertrophy of media and proliferation of intima in the vascular wall, and arteriolar muscularization. There was significantly higher expression of EGF and TIMM-1 in the lung tissue of these patients compared with controls; this could confirm the presence of compensatory mechanisms of lung parenchyma destruction. Strong correlations were found between expression of EGF and TGF β-1, EGF and TIMP-1 which demonstrated a relationship between angiogenesis, proteolysis and fibrogenesis in development of emphysema.