Ex Vivo Expansion Potential of Hematopoietic Stem Cells: A Rare Property Only Partially Predicted by Phenotype

Zhang, Q.; Konturek-Ciesla, A.; Yuan, O.; Bryder, D.

doi:10.1101/2022.06.20.496822

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bioRxiv · 10.1101/2022.06.20.496822

Ex Vivo Expansion Potential of Hematopoietic Stem Cells: A Rare Property Only Partially Predicted by Phenotype

Zhang, Q.·Konturek-Ciesla, A.·Yuan, O.·Bryder, D.

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Abstract

The scarcity of hematopoietic stem cells (HSCs) restricts their use in both clinical settings and experimental research. Here, we examined a recently developed method for expanding rigorously purified murine HSCs ex vivo. After three weeks of culture, only 0.1% of cells exhibited the input HSC phenotype, but these accounted for almost all functional long-term HSC activity. Input HSCs displayed varying potential for ex vivo self-renewal, with alternative outcomes revealed by single cell multimodal RNA- and ATAC-seq profiling. While most HSC progeny offered only transient in vivo reconstitution, these cells efficiently rescued mice from lethal myeloablation. The amplification of functional HSC activity allowed for long-term multilineage engraftment in unconditioned hosts that associated with a return of HSCs to quiescence. Thereby, our findings identify several key considerations for ex vivo HSC expansion, with major implications also for assessment of normal HSC activity. Key point: Ex vivo self-renewal is an intrinsic property of rare candidate HSCs, with implications for assessments of HSC activity by transplantation.

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Zhang, Q., Konturek-Ciesla, A., Yuan, O., Bryder, D.. 2022-06-20. Ex Vivo Expansion Potential of Hematopoietic Stem Cells: A Rare Property Only Partially Predicted by Phenotype. https://doi.org/10.1101/2022.06.20.496822

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