Human serum α1-antitrypsin: Isolation and demonstration of electrophoretic and immunologic heterogeneity

Abstract

Human serum α 1-antitrypsin has been isolated, free of albumin and other serum proteins, by DEAE cellulose and affinity chromatography, and preparative polyacrylamide gel electrophoresis. The fractionation procedures employed did not alter the antitryptic activity of the isolated proteins. α 1-Antitrypsin in native serum or as the isolated material was electrophoretically heterogeneous. Also, a second, immunologically distinct, α 1-antitrypsin protein, similar to that seen in mouse serum, was demonstrated in normal human serum and in the serum of patients with homozygous deficiency of α 1-antitrypsin.