The interaction of cigarette smoke solution with alpha 1-antitrypsin: effect on inhibitory capacity, electrophoretic mobility and immunological measurement.

1. The effects of an aqueous solution of cigarette smoke upon the functional, immunological and electrophoretic assessment of alpha 1-antitrypsin have been studied. 2. The addition of cigarette smoke reduced the inhibitory capacity of the alpha 1-antitrypsin and this was associated with at least a 22% underestimation of the protein concentration by immunological measurement. 3. Furthermore the cigarette-smoke-damaged alpha 1-antitrypsin had an increased electrophoretic mobility in plain agarose compared with the pure protein and was more susceptible to proteolytic damage by elastase. 4. Comparison with results obtained in vivo suggests that oxidative damage to alpha 1-antitrypsin is not the only mechanism involved in the reduction of its inhibitory capacity in secretions, even in non-smokers