Anti-VEGF-Receptor 1 (Vascular Endothelial Growth Factor Receptor 1, VEGFR-1, Flt-1)

Angiogenesis, the formation of new blood vessels, is regulated by the balance between positive and negative endothelial regulatory factors. Vascular endothelial factor receptor-1 (VEGFR-1), also known as FMS-like tyrosine kinase 1 (Flt-1), is a transmembrane receptor tyrosine kinase with high affinity for vascular endothelial growth factor (VEGF) and placenta growth factor (PlGF) (1-3). Binding of VEGF to VEGFR-1 produces receptor dimerization and subsequent signal transduction. Full length VEGFR-1 is characterized by the presence of seven extracellular immunoglobulin-like domains containing the ligand binding region, a single short transmembrane sequence, and an intracellular region with a tyrosine kinase domain (2). VEGF receptors are expressed by vascular endothelial cells and peripheral blood monocytes (4), and have also been observed in colon carcinoma cell lines and colorectal cancer liver metastases (5). In addition to the full-length form of the receptor, a soluble form (sVEGFR-1 or sFlt-1) is generated by alternative splicing of Flt-1 mRNA. This naturally occurring, soluble form of VEGFR-1 is truncated on the C-terminal side of the sixth extracellular Ig-like domain (6), and has been described in various locations, including the serum and plasma of normal males and females, the serum of pregnant women, placenta, and breast tumor tissues (7,8). Soluble VEGFR-1 is an antagonist of VEGF action and an inhibitor of the VEGF signaling pathway, which has been characterized as one of the most important endothelial regulators in human tumor angiogenesis. Applications: Suitable for use in ELISA and Western Blot. Other applications have not been tested. Recommended Dilutions: Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.