More info
Assay Range | 156 - 10,000 pg/mL |
Sensitivity | 10.0 pg/mL |
Size | 96T |
Storage | Store at 2 - 8ºC. Keep reconstituted standard and detection Ab at -20 ºC |
Assay Principle | Sandwich ELISA |
Sample volume | 100 µL final volume, dilution factor varies on samples |
Detection Method | Chromogenic |
Kit Components
1. Recombinant Human OPN standard: 2 vials
2. One 96-well plate precoated with anti- Human OPN Ab
3. Sample diluent buffer: 12 mL - 1
4. Detection antibody: 130 µL, dilution 1:100
5. Streptavidin-HRP: 130 µL, dilution 1:100
6. Antibody diluent buffer: 12 mL x1
7. Streptavidin-HRP diluent buffer: 12 mL x1
8. TMB developing agent: 10 mL x1
9. Stop solution: 10 mL x1.
10. Washing solution (20x): 25 mL x1.
Background
Osteopontin (OPN), also known as bone sialoprotein I (BSP-1 or BNSP), early T-lymphocyte activation (ETA-1), secreted phosphoprotein 1 (SPP1), is a member of the small integrin-binding ligand N-linked glycoprotein (SIBLING) family. Human OPN cDNA encodes a 314 amino acid (aa) precursor protein composed of a predicted 16 aa signal peptide and a highly unusual mature protein fragment with 75 acidic aa and 33 potential Ser/Thr phosphorylation sites. OPN also contains a classic integrin binding site (RGD) that binds integrins αvβ1, αvβ3, αvβ5, α5β1, and α8β1. Osteopontin is highly expressed in mineralized tissues and other tissues including cartilage, kidney, vascular tissues, activated macrophages, lymphocytes, and epithelia. In addition to occurring in the matrix of mineralized tissues, secreted OPN is also found in various biological fluids including blood, milk, urine, and seminal fluid.
OPN has exhibited multiple functions inn bone metabolism, immune regulation, tissue remodeling, cell survival, and tumor progression. It is reported that OPN stimulates the adhesion of osteoclasts to bone, and inhibition of this interaction would block bone resorption. OPN regulates macrophage differentiation and recruitment. It also functions as a chemotactic factor and co-stimulator of T cells to stimulate IL-12 production. OPN knockout mice exhibit deficient Th1 responses and are susceptible to bacterial and viral infection. Expression of OPN has been detected in many tumor types. In cancer patients, increased serum OPN concentration has been associated with increased tumor burden.