Alpha 1-antitrypsin: the PiMM subtypes. Do they play a role in development of chronic obstructive pulmonary diseases?

In a comparative study, we examined 324 sera of the PiMM phenotype by isoelectric focusing. Sera were obtained from 254 healthy individuals, and from 70 patients suffering from chronic obstructive pulmonary disease (COPD). All individuals were examined, a detailed history and chest x-ray films were taken, and lung function tests were performed. The classification into PiMM subtypes according to a modified method, originally described by Genz et al, showed a significantly higher number of subtypes, containing more slowly migrating protein fractions (M2) in the group of patients. Since the prevalence of bronchitic symptoms is unusually common in industry, in workers who are exposed to dust and smoke tobacco, these findings are important, especially in regard to prophylactic measures in industry.