Microcarrier-based expansion process for hMSCs with high vitality and undifferentiated characteristics.

For cell therapy, a high biomass of human mesenchymal stem cells (hMSCs) is required for clinical applications, such as in the form of encapsulated implants. An easy and reproducible microcarrier-based stirred tank reactor cultivation process for hMSCs in 1.68 L scale is described. To avoid medium changes, studies comparing high-glucose DMEM (DMEM-HG) with low-glucose EMEM were performed showing that high-glucose medium has positive effects on cell proliferation and that cell differentiability remains.Studies on the inoculation strategy and cell density, carrier concentration, volume, and stirrer speed were performed and resulted in a set of optimized parameters, inoculation strategy was found to be 45 minutes of static state and 2 minutes of stirring repeated in 4 cycles. The inoculation density was chosen to be 7×103 cells/cm2, and the carrier concentration of glass surface carrier was 25 g/L. For the described reactor system, a stirrer speed of 120 rpm for the inoculation process and a daily increase o...