alpha 1-antitrypsin

alpha 1-Antitrypsin or α1-antitrypsin (A1AT) is a glycoprotein and generally known as serum trypsin inhibitor. The correct name, however, is alpha-1 proteinase inhibitor (A1PI) because it is a serine protease inhibitor (serpin) inhibiting a wide variety of proteases. It protects tissues from enzymes of inflammatory cells, especially elastase, and is present in human blood at 1.5 - 3.5 gram/liter, but the concentration can rise manyfolds upon acute inflammation. In its absence, elastase is free to break down elastin -- which contributes to the elasticity of the lungs -- resulting in respiratory complications such as emphysema leading finally to COPD (chronic obstructive pulmonary disease).
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