EXPANSION OF 3D HUMAN INDUCED PLURIPOTENT STEM CELL AGGREGATES IN BIOREACTORS: BIOPROCESS INTENSIFICATION AND SCALING-UP APPROACHES

摘要

Human induced pluripotent stem cells (hiPSC) are attractive tools for drug screening and disease modeling and promising candidates for cell therapy applications. However, to achieve the high numbers of cells required for these purposes, scalable and clinical-grade technologies must be established. In this study, we use environmentally controlled stirred-tank bioreactors operating in perfusion as a powerful tool for bioprocess intensification of hiPSC production. We demonstrate the importance of controlling the dissolved oxygen concentration at low levels (4% oxygen) and perfusion at 1.3 day~(-1) dilution rate to improve hiPSC growth as 3D aggregates in xeno-free medium (Cellartis? DEF-CS~(TM) 500 Xeno-Free Culture Medium). This strategy allowed for increased cell specific growth rate, maximum volumetric cell concentrations (4.7x10~6 cell/mL) and expansion factors (approximately 19), resulting in an overall improvement of 2.6-fold in cell yields. Extensive cell characterization, including whole proteomic analysis was performed to confirm that the pluripotent phenotype was maintained during culture.