人VEGF基因的克隆及其表达和纯化

he growth and metastases of solid tumors are dependent on the angiogenesis, a procedure of new blood vessel growth in solid tumors and a procedure mediated by numerous inhibitors and activators. Among the activators, VEGF is one of the most potent angiogenic factors and also is the most widely researched angiogenic factor. VEGF plays a biological role by acting on specific VEGF receptor. The VEGF DNA sequence which can bind with VEGF-R1 and VEGF-R2 was synthetised after codon optimization. The synthesized DNA sequence was cloned into the expression factor pET22b for VEGF expression. By optimizing the induction conditions, 27 C, 0.5 mM IPTG and 5 h of induction time was selected as the optimal conditions for induction of VEGF expression. PAGE gel electrophoresis and Western blot analysis showed that the expression of VEGF was successfully induced. This study also found that the VEGF expression mainly in the form of inclusion bodies. Ni-NTA His Bind Resin column was used to purify VEGF and the purity could reach 85%. This study prepares for the future screening of the anti-cancer antibodies that is dependent on VEGF antigen.