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Hiraki-Kamon, K.

Publications and source records attributed to Hiraki-Kamon, K..

2 recordsLinked to original sources

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.

cell biology↗

An improved pipeline for reprogramming human induced pluripotent stem cells with TET1

Human induced pluripotent stem cells (hiPSCs) offer transformative potential for developmental research and therapeutic discovery; however, their variable characteristics are a significant barrier to their broader application. We reprogrammed hiPSCs by adding TET1, a DNA-demethylating dioxygenase, to produce TET1-iPSCs (T-iPSCs) with enhanced epithelialization and differentiation capabilities. A default differentiation survey--designed and implemented in our hiPSC-production pipeline--revealed considerable variation in differentiation capacity across qualitatively pluripotent iPSC clones. By comparing high- differentiation T-iPSCs and conventional iPSCs (C-iPSCs) at the single-cell level, we identified a subpopulation of C-iPSCs in the G0/G1 phase (CDKN2A-positive) exhibiting low TET1 expression and an elevated extraembryonic mesenchymal gene signature. The extraembryonic mesenchymal gene signature is common to iPSCs and quantitatively correlates to default differentiation results. Deviation of C-iPSCs from the cell-cycling embryonic epithelial gene profile was accompanied by DNA hypermethylation concomitant with TET1 insufficiency and the accompanying derepression of poised and Polycomb-repressed enhancers, leading to the derepression of senescence-associated and extraembryonic genes. TET1-facilitated reprogramming can ameliorate these deviations. This study provides a standardized hiPSC- production pipeline and discovers an aspect of TET1 for establishing human pluripotency by remedying the inherent heterogeneities resulting from C-iPSC reprogramming.

cell biology↗