Scale-up from Lab-scale Bioreactor in Pilot-scale Bioreactor for the Production of hCTLA4Ig in Transgenic Rice Suspension Cultures

초록

Before commercial manufacturing in a large-scale setting, scale-up from lab-scale to pilot-scale should be preceded that involves comparison of the growth and production characteristics in bioreactor. Using a 20-L pilot-scale stirred bioreactor (STR), recombinant CTLA4Ig was produced by sugar starvation using RAmy3D promoter in transgenic rice (Oryza sativa L.) cell suspension cultures. As growth parameters, maximum dry cell weight, biomass substrate yield (Yx/s) and specific growth rate (m) in a 5-L STR control culture was 9.2 g/L, 0.18 g/g and 0.19/day, respectively. Those value in a 20-L STR was 9.3 g/L, 0.19 g/g and 0.24/day, respectively. In addition, maximum CTLA4Ig production level reached 50.1 mg/L at day 12, which was 14-fold higher than that in 5-L STR. However, target protein were rapidly degraded because protease activity sharply increased upto 188.6 U/mL in 20-L STR after 10 days. We confirmed the possibility of the successful scale-up for the production of plant-made biopharmaceuticals in transgenic plant cell cultures.