SCALABLE EXPANSION OF HUMAN UMBILICAL CORD MATRIX-AND ADIPOSE TISSUE-DERIVED MESENCHYMAL STEM/STROMAL CELLS AND DERIVED EXOSOMES IN THE SINGLE-USE, VERTICAL-WHEEL BIOREACTOR SYSTEM USING A HUMAN PLATELET LYSATE CULTURE SUPPLEMENT

摘要

Mesenchymal stem/stromal cells (MSC) hold great promise for tissue engineering and regenerative medicine settings due to their multilineage differentiation potential and their intrinsic immunomodulatory and trophic activities. Large cell doses (>1×10~6 cells/kg) are however required for clinical implementation and the success in obtaining those cell numbers is dependent on efficient ex vivo expansion protocols able to comply with Good Manufacturing microcarrier-based cultures in scalable bioreactors using serum-/xenogeneic-free (S/XF) culture components. In this context, a S/XF microcarrier-based culture system was successfully established for the expansion of human UCM and AT MSC using an innovative disposable bioreactor system utilizing the Vertical-Wheel technology (PBS-0.1 MAG with maximum working volume of 100 mL, PBS Biotech) combined with a commercially available fibrinogen-depleted human platelet lysate-based culture supplement (UltraGRO-PURE, AventaCell BioMedical). By optimizing the agitation and feeding regimes, UCM and AT MSC were successfully expanded to maximum cell densities of 5.3 ± 0.4 × 10~5 cell/mL (n=3) and 3.6 ± 0.7 × 10~5 cell/mL (n=3), respectively, after 7 days of culture (cell viability ≥ 94%), while maintaining their identity.