title: An engineered heparin-binding form of VEGF-E (hbVEGF-E). Biological effects in vitro and mobilizatiion of precursor cells.
abstract: Vascular endothelial growth factor (VEGF-A) is the founding member of a family of angiogenic proteins with various binding abilities to three cognate VEGF receptors. Previously, a gene encoding from the genome of parapox orf virus (OV) with about 25% amino acid identity to mammalian VEGF-A was named VEGF-E and shown to bind and specifically activate the vascular endothelial growth factor receptor VEGFR-2 (KDR/flk-1). Here, we have generated a novel heparin-binding form of VEGF-E by introducing the heparin-domain of the human VEGF-A(165) splice variant into the viral VEGF-E protein. Recombinant heparin-binding VEGF-E (hbVEGF-E) is shown to stimulate proliferation and sprout formation of macro- and microvascular endothelial cells to a similar extent as the parental OV-VEGF-E but fails to activate peripheral mononuclear cells. However, hbVEGF-E is more potent in binding competition assays with primary human endothelial cells when compared to the OV-VEGF-E. This can be explained by our finding that binding of hbVEGF-E but not of parental OV-VEGF-E to the VEGFR-2 is strongly increased by the addition of neuropilin-1 (NP-1), a cognate co-receptor for VEGF-A. The engineered hbVEGF-E was compared with the VEGFR-1 selective and also heparin-binding form of placenta growth factor (PlGF-2) in vivo. Both heparin-binding homologues induced mobilization of endothelial progenitor cells from the bone marrow and gave rise to similar colony numbers of myeloic cells in a colony-forming assay. These findings suggest that both VEGFR-1 and VEGFR-2 are involved in stem cell mobilization.
authors.affiliation: Department of Experimental Cardiology, Molecular Cell Biology, Max-Planck-Institute for Physiological and Clinical Research, Bad Nauheim, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Heil
authors.forename: Rita
authors.initials: R
authors.lastname: Mitnacht-Krauss
authors.forename: Katja
authors.initials: K
authors.lastname: Issbrücker
authors.forename: Joop
authors.initials: J
authors.lastname: van den Heuvel
authors.forename: Christoph
authors.initials: C
authors.lastname: Dehio
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schaper
authors.forename: Matthias
authors.initials: M
authors.lastname: Clauss
authors.forename: Herbert A
authors.initials: HA
authors.lastname: Weich
mesh_terms: D001665:Binding Sites; D001854:Bone Marrow Cells / Q000187:drug effects / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D019650:Hematopoietic Stem Cell Mobilization; D006493:Heparin / Q000378:metabolism; D006801:Humans; D018919:Neovascularization, Physiologic / Q000187:drug effects; D011485:Protein Binding; D015202:Protein Engineering; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000494:pharmacology*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000494:pharmacology; D042442:Vascular Endothelial Growth Factors / Q000235:genetics* / Q000494:pharmacology; D014764:Viral Proteins / Q000235:genetics / Q000494:pharmacology
chemical_list: D011993:Recombinant Fusion Proteins; C084758:VEGF-like protein, Orf virus; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D014764:Viral Proteins; D006493:Heparin