Recombinant platelet-derived growth factor A-chain derived from endothelial cells

摘要

A PDGF A-chain clone has been isolated from a human umbilical vein endothelial cell-derived cDNA library, the DNA sequence of which identifies a gene with a 69 base pair deletion in comparison to a previously described cDNA clone from a malignant glioma. It is significant that this clone is derived from a non-transformed normal human cell rather than from a malignant glioma. Therefore, the PDGF A-chain encoded by the gene isolated in this invention represents the normal PDGF A-chain, and variant sequences thereof will also be included.;Accordingly, the present invention provides human PDGF A-chain essentially free of other proteins of human origin. The invention further provides replicable expression vectors incorporating a DNA sequence encoding PDGF A-chain and a self-replicating host cell system transfected thereby resulting in the production of PDGF A-chain or functional fragments thereof in useful quantities and purities. In addition, the PDGF A-chain thereby produced is free of contaminants associated with the protein in its non-recombinant cellular environment.