Description
Principle of the assay: This assay employs a two-site sandwich ELISA to quantitative CTSL1 in Mouse serum, plasma, cell culture supernates, tissue homogenates. An antibody specific for CTSL1 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any CTSL1 present is bound by the immobilized antibody. After removing any unbound substances, a biotin - conjugated antibody specific for CTSL1 is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of CTSL1 bound in the initial step. The color development is stopped and the intensity of the color is measured.
Background: Cathepsin L1 is a protein that in humans is encoded by the CTSL1 gene. The protein encoded by this gene is a lysosomal cysteine protease that plays a major role in intracellular protein catabolism. Its substrates include collagen and elastin, as well as alpha-1 protease inhibitor, a major controlling element of neutrophil elastase activity. The encoded protein has been implicated in several pathologic processes, including myofibril necrosis in myopathies and in myocardial ischemia, and in the renal tubular response to proteinuria. This protein, which is a member of the peptidase C1 family, is a dimer composed of disulfide-linked heavy and light chains, both produced from a single protein precursor. At least two transcript variants encoding the same protein have been found for this gene