Recombinant Mouse VEGFR1/Flt-1 Fc Chimera Protein, CF

Recombinant Mouse VEGFR1/Flt-1 Fc Chimera Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: VEGFR1/Flt-1

VEGFR1 (vascular endothelial growth factor receptor 1), also called Flt‑1 (Fms‑like tyrosine kinase), is a 180 kDa type I transmembrane glycoprotein in the class III subfamily of receptor tyrosine kinases (RTKs) (1, 2). While family members VEGFR1, VEGFR2/KDR/Flk‑1 and VEGFR3/Flt‑4 are all mainly expressed on endothelial cells and play central roles in vasculogenesis, angiogenesis, and lymphangiogenesis, only VEGFR1 is expressed on macrophages, and mainly plays inhibitory roles (1‑3). VEGFR1 expression is also reported on osteoblasts, placental trophoblasts, renal mesangial cells, and some hematopoietic stem cells (1, 2). Like other class III RTKs, mouse VEGFR1 contains a signal peptide (aa 1‑22), an extracellular domain (ECD aa 23‑759) with seven Ig‑like repeats, a transmembrane domain (aa 760‑781) and a cytoplasmic region (aa 782‑1333) with a tyrosine kinase domain and several autocatalytic phosphotyrosine sites. Mouse VEGFR1 ECD shares 91% aa sequence identity with rat and 76‑79% with human, equine, canine and porcine VEGFR1. Soluble forms of the VEGFR1 ECD are produced by alternative splicing, and may also be shed during regulated intracellular proteolysis (4‑10). Both soluble and transmembrane forms can inhibit angiogenesis by binding and sequestering its ligands, VEGF (VEGF‑A), VEGF‑B or PlGF (6‑11). VEGFR1 dimerizes upon ligand binding, which can include heterodimerization with VEGFR2 that modifies VEGFR2‑mediated endothelial proliferation and vessel branching (8, 11, 12). VEGFR1 binds VEGF with higher affinity than does VEGFR2, but shows weaker kinase activity (9, 13). Both PlGF and VEGF induce phosphorylation of transmembrane VEGFR1 (5, 9, 13). While deletion of mouse VEGFR1 is lethal due to overgrowth and disorganization of the vasculature, kinase‑inactive mutants are viable (13, 14). VEGFR1 is up‑regulated during hypoxia, and participates in neovascularization and wound healing (1, 2, 15). VEGFR1 engagement on monocyte/macrophage lineage cells enhances their migration, and release of growth factors and cytokines (1, 3, 13, 16). Lymphangiogenesis, angiogenesis, and growth‑promoting effects of VEGFR1 are thought to result from enhanced migration of macrophages from the bone marrow to tumors and tissues where they recruit endothelial progenitors (3, 16). Circulating levels of VEGFR1 increase during pregnancy and are further elevated in preeclampsia (4, 6, 17).

Related Research Areas

• Airway Inflammation and Remodeling
• Cancer Biomarkers
• Cytokine and Growth Factor Receptors on VSMC
• Endothelial Cell Differentiation Markers
• Endothelial Cell Markers
• Endothelial Progenitor and Endothelial Cell Markers
• HIF Transcription Factors
• Microglia Development
• Myeloid-derived Suppressor Cells (MDSC)
• Preeclampsia
• Receptor Tyrosine Kinases (RTKs)
• Receptor Tyrosine Kinases (RTKs) in the Akt Pathway
• Receptors in the Jak/STAT Pathway
• VEGF Family
• VEGF Receptors and Regulators on Endothelial Cells