Elastases and Emphysema

Many studies have been carried out in the past 10 yr dealing with the possible role of elastase in the pathogenesis of pulmonary emphysema. These include newer observations in animal models revealing augmentation of elastase-induced lesions by lathyrogens or by exposure to cigarette smoke. In general, the animal model experiments have focussed attention on repair-processes in the lung and shown that such processes may exert a major influence on the outcome of the initial proteolytic insult. Human studies exploring correlations between elastase levels in neutrophils or serum and development of disease have provided conflicting data; however, measurement of enzymes in pulmonary secretions have yielded more suggestive results. Assessments of lung elastase inhibitors in humans continue to support the importance of alpha-1-proteinase inhibitor in the protection of the lower respiratory tract, but newer information on locally produced, low molecular weight elastase inhibitors indicates that these, too, may play...