Analysis of proteolytic enzymes and their natural inhibitors in serum and bronchial lavage fluid in atopic bronchial asthma, chronic bronchitis and pneumonia.

The protease-antiprotease balance was evaluated in some respiratory tract diseases. Analysis of the protease activity and the natural inhibitors of proteolytic enzymes was carried out on 10 patients with atopic bronchial asthma, 21 with chronic bronchitis, 12 with pneumonia and 11 health volunteers. Paralelly, the inflammatory potency of bronchial lavage fluid was determined in guinea-pig skin test. In our studies of bronchial lavage fluids some selective changes of proteolytic enzyme activities were documented as follows: in pneumonia patients--the increase of acid and neutral proteases activity; in chronic bronchitis--the moderate increase of activities of all examined proteases and in atopic bronchial asthma--the increase of acid protease activity. Similarly, levels of the natural inhibitors of proteolytic enzymes were selectively elevated: alpha-1-antitrypsin in pneumonia and chronic bronchitis patients and alpha-2-macroglobulin in asthmatics. This finding may suggest that the proteolytic enzymes and their inhibitors play an important role in the respiratory tract pathology. This concept is supported by the high inflammatory response observed with bronchial lavage fluids obtained from pneumonia patients in guinea-pig skin test. The authors suggest that the determination of protease activity and level of the natural inhibitors of proteolytic enzymes in bronchial lavage fluids may be useful for clinical prognosis and pharmacological treatment.