[Stable expression of rhVEGF165 in Chinese hamster ovary cells]

We established a stable Chinese hamster ovary (CHO-S) cell line for recombinant human VEGF165-expressing. We co-transfected GS-expression vector and rhVEGF165 expression plasmid into CHO-S cells, and selected the highest VEGF165-expressing clone as the working cell line to express VEGF165 protein. After 7-day fed-batch culture in a 5 L bioreactor and 3 steps chromatographic purification, we got the rhVEGF165 protein for series of binding and biological activity examination. The production was over 50 mg/L. The purified rhVEGF165 protein was functionally active with a half-maximal Human Umbilical Vein Endothelial Cells (HUVEC) growth-enhancing effect concentration of 1.94 ng/mL. It was slightly better than commercially available Escherichia coli expressing rhVEGF165. So we expressed successfully rhVEGF165 protein in high-level and obtained the fully active rhVEGF165 protein in large quantity.