Deutsch 
Test-Category
ELISA
Pack size
96 Tests
Standard concentrations included in the kit
3.1-50 ng/ml
Possible sample matrix and volumes
| Serum | 50 µl |
| EDTA plasma | 50 µl |
Bone Sialoprotein (BSP) is a glycoprotein, which accounts for approximately 10% of the non-collagenous matrix protein of bones. BSP (as well as other glycoproteins such as osteonectin and osteopontin) plays a regulatory role in bone metabolism, e.g. the control of mineralisation in the formation of new bones and bone resorption. BSP contains an Arg-Gly-Asp (RGD)-sequence, which is essential for the attachment of cells to bone surfaces (Fisher et al., 1990). BSP has important functions in the initiation of hydroxyapatite-crystallisation and in the interaction between bone cells and the mineralised bone matrix.
BSP can be detected in mineralising connective tissue, where the osteoblasts are primarily formed. It has however also been detected in trophoblasts and to a lesser extent in decidua cells.
According to the latest investigations, tumors, which result in calcification and formation of metastases in the bones, can also express BSP. It has been shown that BSP expression in human breast cancer is associated with skeletal metastases (Bellahcene et al. 1996). BSP expression has also been detected in small cell bronchial carcinomas (Bellahcene et al. 1997).
In conclusion, present findings show that bone sialoprotein (BSP) is not only a useful marker for bone tissue changes in the diagnosis of bone metabolic disturbances, but is also a potent and reliable tumor marker, which allows the detection of established or developing bone metastases following primary tumor occurences.
