Quantitative Framework for Assessing Mesenchymal Stem Cell Quality Driven by Poised Enhancer Decommissioning

Mesenchymal stem cell (MSC) heterogeneity and conventional phenotypic criteria limitations represent major bottlenecks in therapeutic manufacturing. Here, we present a framework to prospectively identify naturally superior MSCs by shifting from superficial markers to the digital quantification of fundamental epigenetic flaws in inferior clones. We show that intrinsic MSC functional decline is driven by targeted hypermethylation of poised enhancers, causing paradoxical derepression of developmental genes. We term this process poised enhancer decommissioning (PEnD). By isolating this universal decay axis from donor-specific immunological variability, we translate this complex epigenetic state into a streamlined transcriptomic signature: the Poised Enhancer-related Gene Expression (PErGE) score. Overcoming the limitations of standard in vitro differentiation assays, our approach enables accurate, donor-independent prediction of long-term proliferative potential. Together, our findings establish a mechanism-based biomarker of cellular aging, and provide a readily applicable tool to improve the quality control of next-generation MSC-based therapies.