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Abstract In vivo mesenchymal stem cell (MSC) survival is relevant to therapeutic applications requiring engraftment and potentially to nonengraftment applications as well. MSCs are a mixture of progenitors at different stages of cellular aging, but the contribution of this heterogeneity to the survival of MSC implants is unknown. Here, we employ a biomarker of cellular aging, the decoy TRAIL receptor CD264, to compare the survival kinetics of two cell populations in human bone marrow MSC (hBM‐MSC) cultures. Sorted CD264+hBM‐MSCs from two age‐matched donors have elevated β‐galactosidase activity, decreased differentiation potential and form in vitro colonies inefficiently relative to CD264−hBM‐MSCs. Counterintuitive to their aging phenotype, CD264+hBM‐MSCs exhibited comparable survival to matched CD264−hBM‐MSCs from the same culture during in vitro colony formation and in vivo when implanted ectopically in immunodeficient NIH III mice. In vitro and in vivo survival of these two cell populations were independent of colony‐forming efficiency. These findings have ramifications for the preparation of hBM‐MSC therapies given the prevalence of aging CD264+cells in hBM‐MSC cultures and the popularity of colony‐forming efficiency as a quality control metric in preclinical and clinical studies with MSCs.
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This content will become publicly available on April 1, 2026
RNA sequencing identifies MAP1A and PTTG1 as predictive genes of aging CD264+ human mesenchymal stem cells at an early passage
Abstract Molecular profiles of mesenchymal stem cells (MSCs) are needed to standardize the composition and effectiveness of MSC therapeutics. This study employs RNA sequencing to identify genes to be used in concert with CD264 as a molecular profile of aging MSCs at a clinically relevant culture passage. CD264−and CD264+populations were isolated by fluorescence-activated cell sorting from passage 4 MSC cultures. CD264+MSCs exhibited an aging phenotype relative to their CD264−counterpart. Donor-matched CD264−/+mRNA samples from 5 donors were subjected to pair-ended, next-generation sequencing. An independent set of 5 donor MSCs was used to validate differential expression of select genes with quantitative reverse transcription PCR. Pairwise differential expression analysis identified 2,322 downregulated genes and 2,695 upregulated genes in CD264+MSCs relative to donor-matched CD264−MSCs with a Benjamini–Hochberg adjustedp-value (BHpadj) < 0.1. Nearly 25% of these genes were unique to CD264−/+MSCs and not differentially expressed at a significance level of BHpadj < 0.1 in previous RNA sequencing studies of early- vs. late-passage MSCs. Least Absolute Shrinkage and Selection Operator regression identified microtubule-associated protein 1A (MAP1A) and pituitary tumor-transforming gene 1 (PTTG1) as predictive genes of CD264+MSCs. CombinedMAP1AandPTTG1expression correctly classified CD264 status of MSC samples with an accuracy of 100%. Differential expression and predictive ability ofMAP1AandPTTG1compared favorably with that of existing senescence markers expressed in early passage CD264−/+MSCs. This study provides the first linkage ofMAP1Ato CD264, aging and senescence. Our findings have application as quality metrics to standardize the composition of MSC therapies and as molecular targets to slow/reverse cellular aging.
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- Award ID(s):
- 1604129
- PAR ID:
- 10595722
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Cytotechnology
- Volume:
- 77
- Issue:
- 2
- ISSN:
- 0920-9069
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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