University of Chile Santiago, Region Metropolitana, Chile
Abstract: Mesenchymal stem cells (MSCs) derived from the Wharton’s jelly of the human umbilical cord (hWJ-MSC) are a promising source for cell therapy due to their ease of procurement and expansion capacity. However, scalable and efficient processes that maintain cell viability and multipotency are required for clinical applications. This study focuses on scaling up hWJ-MSC expansion from 150 mL spinner flasks to 500 mL bioreactors using Cytodex 1 microcarriers. Spinner flask cultures, starting with an inoculum of 1.6E+05 viable cells/mL, achieved a maximum density of 2E+06 viable cells/mL, yielding 300 million viable cells in 150 mL. When supplementing cultures under xeno-free conditions with hPL, a significantly lower yield was observed compared to FBS supplementation, with an 83% reduction in biomass due to suboptimal cell adhesion to the microcarriers. However, treating Cytodex 1 microcarriers with APTES-GA improved adhesion, resulting in a 39% increase in biomass compared to uncoated microcarriers. Bioreactor conditions, including agitation speed, pH, and oxygenation, were optimized to achieve successful scale-up from spinner flasks, replicating the concentrations obtained in smaller-scale systems. Cells were characterized according to ISCT criteria by analyzing morphology, surface markers, and trilineage differentiation potential. Metabolic profiling of the bioreactor cultures was performed to evaluate glucose consumption and lactate production. This work represents a significant step toward scalable and clinically relevant systems for hWJ-MSC production in advanced cell therapy applications.
Funding Source: Supported by ANID-FONDECYT #11230208, ANID-Basal funds for CeBiB #AFB240001 and #FB0001, and the ANID-National Master’s Grant #22240802.
