| Species : |
Human |
| Source : |
Insect Cells |
| Tag : |
Non |
| Description : |
Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor. |
| Physical Appearance : |
Sterile Filtered White lyophilized (freeze-dried) powder. |
| Purity : |
Greater than 90.0% as determined by: (a) Analysis by RP-HPLC. (b) Analysis by SDS-PAGE.GE. |
| Formulation : |
VEGFR-1 D1-4 was lyophilized from a concentrated (1mg/ml) sterile solution containing no additives. |
| Solubility : |
It is recommended to reconstitute the lyophilized sVEGFR-1 D4 in sterile water not less than 100 µg/ml, which can then be further diluted to other aqueous solutions. |
| Biological Activity : |
The activity of sVEGFR-1D1-4 was determined by its ability to abolish the binding of iodinated VEGF to solid surfaces or cell surfaces, and in Far-Western and cross-linking experiments with iodinated VEGF. |
| Storage : |
Lyophilized FLT-1 although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution FLT1 should be stored at 4°Cbetween 2-7 days and for future use below -18°C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Please prevent freeze-thaw cycles. |