AGP is a 52 kDA serine protease inhibitor (serpin) in blood, which protects tissue from enzymes from inflammatory cells, especially elastase. In certain acute phase inflammatory reactions, AGP is elevated in order to limit the damage caused by activated neutrophil granulocytes and their enzyme elastase. Disorders of AGP include AGP deficiency, a hereditary disorder that can lead to severe tissue breakdown during inflammation. This may result in pulmonary emphysema and liver cirrhosis, in severe cases.