Neutrophil Elastase (NE, EC 3.4.21.37, leukocyte elastase, elastase 2, or serine elastase) is a cytotoxic serine protease. It is stored in the azurophil granules of neutrophil granulocyte and is released following cell stimulation, e.g. by pathogens, immune complexes or chemotactic agents (PMA). When the extracellular NE concentration exceeds the buffering capacity of endogenous inhibitors, it causes degradation of a wide range of extracellular matrix proteins, including fibronectin, laminin, proteoglycans, collagens, and elastin. Extracellular elastase is implicated in the signs, symptoms and disease progression of inflammatory lung disorders (such as cystic fibrosis, COPD, lung emphysema) via its role in the inflammatory processes, mucus overproduction and lung tissue damage. BioVision's Neutrophil Elastase Activity Assay Kit utilizes the ability of NE to proteolytically cleave a synthetic substrate and release a fluorophore, AFC, which can be easily quantified by fluorescence microplate readers. This assay kit is simple, rapid and can detect as low as 1 ng of Neutrophil Elastase in a variety of samples.