The Vascular Endothelial Growth Factor Receptor Flt-1 Mediates Biological Activities

Placenta growth factor stimulates MAP kinase and mitogenicity but not phospholipase C-γ and migration of endothelial cells expressing Flt 1

“…In addition, it is likely that migration can be modulated by other signal transduction pathways, potentially in a cell speci®c manner. Indeed, PlGF has been reported to induce migration of monocytes expressing Flt 1 (Clauss et al, 1996). It is important to continue the characterisation of the signal transduction properties of Flt 1 and KDR in order to understand their in vivo function.…”

“…Two related but distinct receptors for VEGF have been identi®ed, Flt 1 (VEGFR-1) (de Vries et al, 1992) and KDR/Flk 1 (VEGFR-2) (Terman et al, 1992). Both receptor types are expressed in endothelial cells, but expression of KDR has also been identi®ed in pancreatic duct precursor cells (O È berg et al, 1994), and expression of Flt 1 has been demonstrated in monocytes (Clauss et al, 1996). The receptors have a similar structural organisation, with their extracellular parts composed of seven immunoglobulin-like loops and their intracellular tyrosine kinase domains interrupted by kinase inserts of about seventy amino acid residues.…”

“…Furthermore, NIH3T3 cells expressing Flt 1 fail to undergo proliferation in response to VEGF treatment (Seetharam et al, 1995). Recently however, Flt 1 endogenously expressed in monocytes was reported to mediate induction of tissue factor production and chemotaxis in monocytes upon VEGF-and PlGFstimulation (Clauss et al, 1996). In addition, PlGF has been shown to have a weak growth stimulatory e ect on human umbilical vein endothelial (HUVE) cells (Sawano et al, 1996).…”

Immunodetection and quantification of vascular endothelial growth factor receptor‐3 in human malignant tumor tissues

“…The procedure was similar to that described previously for the polyclonal sVEGFR-2 antibody. 16 Briefly, a total amount of 1.2 mg soluble VEGFR-3 protein, comprising the whole extracellular domain 17 (amino acid 26 to 725) purified from baculovirus infected insect cells, was used for immunization of 2 New Zealand white rabbits. Total IgG from rabbit serum was isolated using HiTrap Protein-A Sepharose columns (Amersham Bioscience, Freiburg) and then antigen-affinity purification was performed by 0.5 mg recombinant soluble VEGFR-3 on a NHSactivated HiTrap column (Amersham Bioscience, Freiburg).…”

Roles of two VEGF receptors, Flt-1 and KDR, in the signal transduction of VEGF effects in human vascular endothelial cells

“…The importance of KDR/Flk-1 is further emphasized by using mutant VEGF which only binds to KDR (Keyt et al, 1996) or KDR antisense oligonucleotides (Bernatchez et al, 1999). However, Flt-1 does play a role in VEGF-stimulated migration of monocytes/ macrophages which express only Flt-1 (Shen et al, 1993;Barleon et al, 1996;Clauss et al, 1996).…”