Scale-up a stem cell process may be challenging: small variations in physicochemical parameters (surface characteristics, pH and dissolved oxygen) can heavily impact stem cell growth and behavior.
The Integrity® Xpansion™ multiplate bioreactors have been designed to enable an easy transfer from multiple-tray stacks process by offering the same cell growth environment: stacked hydrophylized polystyrene plates in a compact and closed system (from 10 to 200 plates per bioreactor equivalent respectively to 6120cm² and 122400cm²). As there is no headspace between plates, gas regulation occurs via silicon tubing placed in a central column, enabling the regulation of the critical cell culture parameters (pH and dissolved oxygen).
Hepatic progenitor stem cell process in multilayer trays has been successfully transposed in less than 6 months into the Xpansion bioreactor, without losing the cell therapeutic potency. First cultures were performed in Xpansion 10 plates allowing to define optimal cell culture parameters. Harvested cell densities of 2.1×104 cells/cm2 at greater than 90% viability were achieved in a controlled reproducible culture environment. Afterwards, cells have been cultivated in Xpansion-50 plates and Xpansion-180 plates, before fine-tuning the complete process. At the final scale – Xpansion 180 plates (110160 cm²) – harvested cell densities of 2.1×104 cells/cm2 were maintained and lead to a production of 2.3×109 cells.