Vascular endothelial cell growth factor variants and uses thereof

Abstract

The present invention provides VEGF variants having at least a single amino acid mutation in the native VEGF sequence and selective binding affinity for either the KDR receptor or the FLT-1 receptor. Methods of making the VEGF variants and methods of using the VEGF variants are also provided.

1 - 19 . (canceled)  
     
     
         20 . A variant of a native vascular endothelial growth cell factor (VEGF) that exhibits selective binding affinity for KDR receptor as compared to native VEGF, the VEGF variant comprising an amino acid substitution wherein at least amino acid residues D63 and L66 of native VEGF are substituted.  
     
     
         21 . The VEGF variant of  claim 20 , wherein the amino acid substitution comprises D63S, L66R, or L66T.  
     
     
         22 . The VEGF variant of  claim 20 , wherein the amino acid substitution comprises D63S and L66R.  
     
     
         23 . The VEGF variant of  claim 20 , wherein the VEGF variant comprises an amino acid substitution at D63, G65, and L66 of native VEGF.  
     
     
         24 . The VEGF variant of  claim 23 , wherein the amino acid substitution comprises D63S, G65M, and L66T.  
     
     
         25 . An isolated polynucleotide encoding the VEGF variant of  claim 20 .  
     
     
         26 . A vector comprising the polynucleotide of  claim 25 .  
     
     
         27 . A host cell comprising the vector of  claim 26 .  
     
     
         28 . A composition comprising the VEGF variant of  claim 20  and a carrier.  
     
     
         29 . The composition of  claim 28 , wherein the carrier is a pharmaceutically acceptable carrier.  
     
     
         30 . An assay for detecting the expression or presence of KDR receptor, comprising contacting a cell or tissue with a VEGF variant of  claim 20  and assaying for binding of the VEGF variant to the cell or tissue.  
     
     
         31 . A method for stimulating phosphorylation of a KDR receptor, comprising contacting a cell or tissue with a VEGF variant of  claim 20  in amount effective to stimulate phosphorylation of the KDR receptor.  
     
     
         32 . A method for stimulating MAP kinase activation, comprising contacting a cell or tissue with a VEGF variant of  claim 20  in amount effective to stimulate phosphorylation of MAP kinase.  
     
     
         33 . A method for stimulating PLC-gamma activation, comprising contacting a cell or tissue with a VEGF variant of  claim 20  in amount effective to stimulate phosphorylation of PLC-gamma.  
     
     
         34 . A method for stimulating PI 3′-kinase activation, comprising contacting a cell or tissue with a VEGF variant of  claim 20  in amount effective to stimulate phosphorylation of PI 3′-kinase.  
     
     
         35 . A method for stimulating vasculogenesis or angiogenesis, comprising administering a VEGF variant of  claim 20 .  
     
     
         36 . A method for promoting the migration of endothelial cells, comprising contacting endothelial cells expressing KDR receptor with an effective amount of a VEGF variant of  claim 20.