Molecular cloning and expression of human granulocyte-macrophage colony stimulating factor in Escherichia coli system.

Human granulocyte-macrophage stimulating factor (hGM-CSF) is an important hematopoietic growth factor. hGM-CSF is able to stimulate hematopoietic progenitors to produce granulocytes, macrophages and eosinophils. hGM-CSF also shows the potential to treat myeloid leukemias. In order to prepare enough hGM-CSF, a genetically engineered strain E. coli HB101/pZW.GM47 was constructed by DNA recombination technologies in the present study, and characterized by restriction analysis, DNA sequencing, SDS-PAGE, Western blotting and bioassays. The strain has been shown to produce a 14kDa mature hGM-CSF protein with expression level higher than 40% and a specific activity of 5.0 x 10(7) u/mg which shows a good potential for clinical applications.