Establishment of a transgenic tobacco cell suspension culture system for producing murine granulocyte-macrophage colony stimulating factor

We tested if murine granulocyte-macrophage colony stimulating factor (mGM-CSF) is produced as a biologically active form through plant cell culture. The mGM-CSF gene was cloned into the plant expression vector, pBI121, and Ti-plasmid mediated transformation of tobacco leaves was conducted using Agrobacterium tumefaciens harboring the recombinant mGM-CSF (rmGM-CSF) gene. Cell suspension culture was established from the leaf-derived calli of transgenic tobacco plants. Northern blot analysis indicated the expression of the introduced mGM-CSF gene in both transgenic plant and cell suspension cultures. In addition, the biological activity of rmGM-CSF from plant cell culture was confirmed by measuring the proliferation of GM-CSF dependent FDC-P1 cells.