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bioRxiv · 10.1101/2025.06.11.659017

ATP2B1 expression identifies human hematopoietic stem cells across ontogeny with superior repopulation and self-renewal capacity

Varesi, A.·Nagree, M.·Di Biasio, I.·Zeng, A. G. X.·Shah, S.·Kim, H.·Zhang, M.·Murison, A.·Dick, J. E.·Xie, S. Z.
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Abstract

Long-term hematopoietic stem cells (LT-HSC) maintain lifelong hematopoiesis while preserving the stem cell compartment through self-renewal. The human LT-HSC compartment is molecularly and functionally heterogeneous and also varies across ontogeny. Dissecting the molecular basis for this variation is impeded by the absence of immunophenotypic markers to resolve LT-HSC heterogeneity. Here, we identified ATPase plasma membrane Ca2+transporting 1 (ATP2B1/PMCA1) as a novel cell surface marker that is heterogeneously expressed by CD49f+ LT-HSC across ontogeny. ATP2B1 immunophenotypic expression stratified human CD49f+ LT-HSC from fetal liver (FL), neonatal cord blood (CB) and adult mobilized peripheral blood (mPB) sources into functionally distinct subpopulations in single-cell (sc) clonogenic assays. CD49f+ATP2B1+ LT-HSC exhibited superior long-term repopulation and self-renewal capacities in vivo compared to CD49f+ATP2B1- LT-HSC. Molecular profiling by scMultiome and immunofluorescence microscopy point to enrichment of an HSC self-renewal program that includes the TFEB-endolysosomal axis in CD49f+ATP2B1+ LT-HSC. Our study provides a new tool to dissect the heterogeneous molecular programs in LT-HSC across ontogeny.

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Varesi, A., Nagree, M., Di Biasio, I., Zeng, A. G. X., Shah, S., Kim, H., Zhang, M., Murison, A., Dick, J. E., Xie, S. Z.. 2025-06-11. ATP2B1 expression identifies human hematopoietic stem cells across ontogeny with superior repopulation and self-renewal capacity. https://doi.org/10.1101/2025.06.11.659017

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