Efficient Expansion and Delayed Senescence of Human Umbilical Cord Mesenchymal Stem Cells by Microcarrier-Bioreactor System

Human umbilical cord mesenchymal stem cells (hUC-MSCs) are widely used in cell therapy due to their powerful immunomodulatory and tissue regenerative capabilities. In order to meet the number and quality of cells for clinical applications, we developed a hUC-MSCs culture process based on homemade microcarriers and stirred bioreactors. In this study, the biological properties of hUC-MSCs amplified by planar culture and microcarrier bioreactor systems are systematically compared. It was found that microcarrier-expanded hUC-MSCs had a relatively lower degree of aging, relatively stronger proliferation capacity, and fewer cells stayed in the cell cycle retardation period. At the same time, RNA-seq was used to compare the differences in gene expression between the two cultures, and the pathways and genes related to cell aging were identified. Comparing the transcription levels of these aging-related gene sets can also confirm that cells cultured by microcarrier reactors are more youthful. Results show that our reactor culture method greatly improved the cell proliferation efficiency, while maintaining the basic properties and younger state of stem cells. Develop a culture process for hUC-MSCs based on homemade microcarriers and stirred bioreactors, systematically compare the biological characteristics of hUC-MSCs amplified by planar culture and microcarrier bioreactor systems, and compare gene expression differences between the two cultures by RNA-seq to identify pathways and genes associated with cellular senescence.