Matrix metalloproteinases (MMPs) belong to a family of secreted or membrane-associated proteins capable of digesting extracellular matrix components. MMP-12 (macrophage elastase) is implicated in the pathology of many diseases such as emphysema, aortic lesions and cancer. It has recently been shown to play a role in the pathogenesis of rheumatoid arthritis. The SensoLyte® 490 MMP-12 Assay Kit is a complete assay system designed to continuously analyze MMP-12 activity or to screen for MMP-12 inhibitors by using a fluorogenic MMP-12 substrate. The assays are performed in a convenient 96-well or 384-well microplate format. It provides speed, convenience and accuracy in analyzing MMP-12 and in screening MMP-12 inhibitors.