Description
Intended Uses: For the quantitative detection of Pig Osteopontin (OPN) concentration in serum, plasma and other biological fluids.
Principle of the Assay::This assay employs a two-site sandwich ELISA to quantitate OPN in Pig serum, plasma. An antibody specific for OPN has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any OPN present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for OPN 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 OPN bound in the initial step. The color development is stopped and the intensity of the color is measured.
Background/Introduction: Osteopontin (OPN), is a secreted multifunctional glyco-phosphoprotein with roles in bone metabolism, immune regulation, tissue remodeling, cell survival, and tumor progression. Gene structure and chromosomal location identify OPN as a member of the small integrin-binding ligand N-linked glycoprotein (SIBLING) family that also includes BSP, BMP1, DSPP, ENAM and MEPE. Murine OPN issynthesized as a 294 amino acid (aa) precursor protein with a predicted 16 aa signal peptide and a highly unusual mature protein sequence, containing 68 acidic aa and 23 potential Ser/Thr phosphorylation sites. Although the predicted molecular weight of OPN is 31 kDa, phosphorylation and N- and O-glycosylation may allow it to appear as large as 75 kDa. Variability in post-translational modifications can influence the activity of OPN