The mechanism of airway obstruction in the development of COPD

Cigarette smoking is the major cause of chronic obstructive pulmonary disease (COPD) and it is generally accepted that proteinases released from neutrophils and/or macrophages are involved in the development of emphysema. It remained unknown why only a small portion of smokers develops clinically apparent emphysema and which cells and/or proteinases play a key role in the pathogenesis of COPD. Structural cells in the lungs such as epithelial cells and endothelial cells may also be involved in cell death and repair. Individual genetic background may regulate the function of these cells in response to cigarette smoke and is related to the susceptibility to pulmonary emphysema.