CLONING AND EXPRESSING HG-CSF (HUMAN GRANULOCYTE COLONY STIMULATING FACTOR) BEING FUSED WITH FERRITIN HEAVY-CHAIN IN E. COLI

Abstract

G-CSF is a cytokine that stimulates the proliferation, differentiation, function of mature neutrophils and is generally used for treatment of neutropenia in cancer patients under chemotherapy. In this study, we report results on the cloning and expression of hG-CSF being fused with the heavy-chain (FTN-H) of human ferritin, which had been showed to be capable of facilitate the folding of several human protein expressed in E. coli. The hg-csf gene and gene encoding FTN-H were inserted into plasmid pET28a to form expression vector pET-FHG. 6xHis tag and TEV sequence (being recognized and cleaved by TEV protease) was added between of G-CSF and FTN-H to facilitate G-CSF purification and recovery afterwards. pET-FHG was transformed into E. coli BL21(DE3). The expression of hG-CSF was induced by IPTG and confirmed by SDS-PAGE and Western blot using anti-hG-CSF antibody.