Osteopontin N-Half ELISA Kit

INTENDED USE

Human osteopontin N-half ELISA kit is a reliable quantitative method for measuring OPN N-half (osteopontin N-half, N-terminal OPN) in human EDTA plasma, urine, cell culture media and synovial fluid. This assay has a sensitivity detection limit of 3.0 pmol/L.

BACKGROUND

Osteopontin (OPN) is a highly acidic calcium binding glycosylated phosphoprotein, also a secretory glycoprotein that was first isolated from the bone. It has a molecular weight which can vary as a result of phosphorylation and sugar chain formation, in general it can be anything from 44 to 66kDa. It has a unique characteristic in that it can assume a number of different molecular forms in vivo as a result of; phosphorylation, RNA splicing, degradation by protease, saccharification, sulfation and glycosylation. It also contains an Arg-Gly-Asp (RGD) amino acid sequence, this motif allows OPN to bind members of the integrin family (such as avb3) of cell surface receptors.

The following assay procedure is designed for measuring the N-terminal osteopontin (OPN N-half) fragment cleaved by thrombin. Therefore, any other OPN molecules that are not cleaved by thrombin will not be detected. It is known to be able to coexist with thrombin locally in tissues that are; inflamed, injured, vascularized and tumors. This ability to coexist with thrombin can help to increase the likelihood of proteolysis and there is growing evidence that this may have a vital physiological role.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• Microtitre Plate: Coated wells with osteopontin N-half antigen (34E3).
• HRP Conjugated: Consists of anti-human OPN N-half (mouse O-165) conjugated to horseradish peroxidase (HRP).
• Standards: concentration 0 – 400 pmol/L, made from recombinant.
• EIA Buffer.
• Label Antibody Solution.
• TMB Chromogen Solution.
• Wash Buffer.
• Stop Solution.

SENSITIVITY

The minimum sensitivity detection limit of human N-terminal OPN (OPN N-half) using current OPN N-half ELISA kit was approximately 3.0 pmol/L. The dynamic range for this assay is 6.25 – 400 pmol/L.

ASSAY CHARACTERISTICS

– Titer Assay: 92.5 – 108.7%
– Added Recovery (Accuracy): 87.9 – 106.9%
– Intra Assay: 1.7 – 9.8%
– Inter Assay: 4.1 – 14.2%
– Sensitivity: 3.09 pmol/L

REFERENCES

1. Molecular cloning and sequencing of cDNA encoding urinary stone protein, which is identical to osteopontin. Biochem. Biophys. Res. Commun. (1992) 184: 859-864. Kohri, K., et al.
2. Phosphate is a specific signal for induction of osteopontin-gene expression. Proc. Nat. Acad. Sci. (2000) 97: 8352-8357. Beck, G. R., Jr.; Zerler, B.; Moran, E.
3. Osteopontin as a potential diagnostic biomarker for ovarian cancer. JAMA (2002) 287 (13): 1671-1679. Kim J-H., et al.
4. Enhanced local production of osteopontin in rheumatoid joints. J Rheumatol. (2002) 29 (10): 2061-2067. Ohshima S., et al.

ADDITIONAL INFORMATION

• Full Name: Osteopontin N-Half ELISA Kit
• Reactivity: Human
• Sample Type: Plasma (EDTA), Synovial Fluid, Cell Culture Media, Urine
• Sensitivity:  3.0 pmol/L

OTHER RELATED ELISA KITS

• Human Osteopontin ELISA Kit
• Mouse Osteopontin ELISA Kit
• Intact PTH ELISA Kit