Large-Scale Expression, Purification of Bioactive Recombinant Human FGF6 in E. coli and the Mechanisms of Its Myocardial Protection

Abstract

Fibroblast growth factor 6 (FGF6) known as hst-2 belonging to the FGF4 subfamily has extensive biological activities which include regulating cell proliferation, angiogenesis, as well as facilitating muscle regeneration. To further investigate the structural and biochemical effects of FGF6, we had firstly established a successful E. coli system for large-scale production of recombinant human FGF6 (rhFGF6) with remarkable biological activity. We performed renaturation of denatured rhFGF6 on a SP Sepharose column followed by washing with buffer containing 600 mM NaCl, and further purification on a Heparin Sepharose column. The yield of purified rhFGF6 was nearly 110 mg per liter of bacterial broth and the purity of rhFGF6 was up to 97% which was demonstrated by HPLC analysis. In vitro studies showed that the rhFGF6 protein could significantly stimulate the proliferation of NIH 3T3 cells and C2C12 myoblast cells, besides protecting H9c2 myocardial cells against H2O2 induced injury through MAPK-Caspase-3 dependent pathway. The approach described here could provide an efficient avenue to produce active rhFGF6.