Patent ID: 8906648

Claim:
A process for recovering a heparin binding protein from a prokaryotic cell culture, wherein said heparin binding protein is vascular endothelial growth factor (VEGF), the process comprising the steps of (a) isolating said heparin binding protein from the periplasm of said prokaryotic cell culture; (b) denaturing said isolated heparin binding protein in a first buffered solution comprising a chaotropic agent and a reducing agent; (c) incubating said denatured heparin binding protein in a second buffered solution comprising a chaotropic agent and a sulfated polyanionic agent, wherein said sulfated polyanionic agent is dextran sulfate or sodium sulfate, for such a time and under such conditions that refolding of the heparin binding protein occurs; and (d) recovering said refolded heparin binding protein, wherein there is about a 2- to 5-fold increase in refolded heparin binding protein recovered compared to incubating with no sulfated polyanionic agent.