This Eagle Biosciences MMP-13 ELISA Assay Kit is a quantitative assay is based on a two site sandwich format. A highly specific monoclonal antibody for the activated form of MMP-13 is immobilised on the plate. MMP-13 will be bound to the wells, other components of the sample are removed by aspiration and washing of the plate. The analyte is detected in two steps using a secondary biotin-labeled antibody and a highly polymerised streptavidin-peroxidase conjugate. Any excess is removed by aspiration and washing after each detection step. The amount of peroxidase bound to each well is determined by the addition of TMB Substrate. The reaction is stopped by adding the Stop Solution, and the resultant colour is read in a microtiter plate reader at 450 nm. The concentration of activated MMP-13 in a sample is determined by interpolation from the standard curve. One kit contains reagents for 96 determinations, thus allowing the measurement of one standard curve and 40 samples in duplicate. Sample Types: serum, synovial fluid, cell culture supernatants. Range: 32 -2000 pg/ml. Sensitivity: 7 pg/ml. Time: 4.25 hours ? Matrix Metalloproteinases (MMPs) comprise a family of secreted and membrane-bound endopeptidases which hydrolyse extracellular matrix proteins (1). Based on their preferred substrates and on structural features MMPs can be divided into collagenases, gelatinases, stromelysins and membrane-type matrix metalloproteinases. Their activity is tightly regulated by inhibitors (2). Collagenase 3 (MMP-13) is a secreted 452 residue protein which is released from cells as an inactive zymogen and activated extracellularly by removal of its propeptide. Cleavage of the 84 residue propeptide can be catalysed by other MMPs such as MMP-2 and MMP-14, or by other proteases like plasmin (3). Under normal conditions, MMP-13 is expressed during embryogenesis (fetal bone development) and is present only at very low levels in adult tissue. However, this enzyme is reported to be involved in the development and metastasis of breast and lung carcinomas, chondrosarcomas and osteosarcomas, head and neck carcinomas and some forms of skin cancer (4). Additionally, this enzyme plays an important role in degenerative bone diseases including osteoarthritis (5) and rheumatoid arthritis (6). Our MMP-13 test kit enables the user to measure the concentration of this putative marker enzyme in body fluids such as serum and synovial fluid with high sensitivity. The ELISA MMP-13 is specific for the activated enzyme.