Overproduction of recombinant human VEGF (vascular endothelial growth factor) in Chinese hamster ovary cells

Vascular endothelial growth factors (VEGFs) are a family of proteins that mediate angiogenesis. VEGF(165) is a VEGF-A isoform and has been extensively studied owing to its potential use in therapeutic angiogenesis. This study established Chinese hamster ovary (CHO) cells overexpressing recombinant human VEGF(165) (rhVEGF(165)) protein. The production rate of the established CHO cells was over 80 mg/l of rhVEGF(165) protein from a 7-day batch culture process using a 7.5-1 bioreactor with a 5-1 working volume and serum-free medium. The rhVEGF(165) protein was purified to homogeneity from the culture supernatant using a two-step chromatographic procedure that resulted in a 48%, recovery rate. The purified rhVEGF(165) protein was a glycosylated homodimeric protein with a higher molecular weight (MW) than the protein expressed from insect cells, suggesting that the glycosylation of the rhVEGF(165) protein in CHO cells differed from that in insect cells. The purified rhVEGF(165) protein in this study was functionally active with a half-maximal effective concentration of 3.8 ng/ml and specific activity of 2.5 x 10(5) U/mg.