ALPHA-1-ANTITRYPSIN AND ITS DEFICIENCY STATE

Alpha-1-antitrypsin (alpha-1-AT) is the major protease inhibitor in blood plasma. It plays a protective role by inhibiting several endogenous proteases. It occurs in the form of several variants and is highly pleomorphic. Some variants such as the S and Z variants are associated with a reduced alpha-1-AT level resulting in a condition referred to as alpha-1-AT deficiency. In a large percentage of alpha-1-AT deficient individuals, the deficiency state is associated with lung and liver diseases. In this paper the biochemistry, genetics and pathophysiology of alpha-1-AT are reviewed and clinical syndromes associated with alpha-1-AT deficiency are presented.