Enhancement of recombinant human macrophage colony-stimulating factor production using culture systems with porous polymeric microspheres

Recombinant human macrophage colony-stimulating factor (M-CSF) was produced in Chinese hamster ovary (CHO) cells. Gas foamed lightweight porous microspheres were prepared from the biodegradable polymer poly(lactic-co-glycolic acid) (PLGA) and used as microcarriers. These porous microcarriers provided a large surface area for cell anchorage and growth. The microcarriers provided support that also reduced cell damage resulting from the shear stress generated in the spinner flask. Cells cultured with 1% or 5% NH4HCO3–PLGA porous microcarriers had a slower growth rate than cells grown on collagen-coated dextran, Cytodex 3. Culture in microcarrier systems with porous PLGA beads led to high protein yields without the need of any chemical additives. The M-CSF yield in these cultures was up to 4-fold higher than that in Cytodex 3-based cultures. The results suggested that the cells cultured at a lower growth rate extended the life-span of cells and enhanced total M-CSF production significantly.