Donor-to-Donor Heterogeneity in the Clonal Dynamics of Transplanted Human Cord Blood Stem Cells in Murine Xenografts

Mirjam Belderbos, Sabrina Jacobs, Taco Koster, Bertien Ausema, Ellen Weersing, Erik Zwart, Gerald Haan, de, Leonid Bystrykh

Research output: Contribution to journalArticleAcademicpeer-review

4 Citations (Scopus)
14 Downloads (Pure)

Abstract

Umbilical cord blood (UCB) provides an alternative source of hematopoietic stem cells (HSCs) for allogeneic transplantation. Administration of sufficient donor HSCs is critical to restore recipient hematopoiesis and to maintain long-term polyclonal blood formation. However, due to lack of unique markers, the frequency of HSCs among UCB CD34(+) cells is the subject of ongoing debate, urging for reproducible strategies for their counting. Here, we used cellular barcoding to determine the frequency and clonal dynamics of human UCB HSCs and to determine how data analysis methods affect these parameters. We transplanted lentivirally barcoded CD34(+) cells from 20 UCB donors into Nod/Scid/IL2Ry(-/-) (NSG) mice (n = 30). Twelve recipients (of 8 UCB donors) engrafted with >1% GFP(+) cells, allowing for clonal analysis by multiplexed barcode deep sequencing. Using multiple definitions of clonal diversity and strategies for data filtering, we demonstrate that differences in data analysis can change clonal counts by several orders of magnitude and propose methods to improve their consistency. Using these methods, we show that the frequency of NSG-repopulating cells was low (median similar to 1 HSC/10(4) CD34(+) UCB cells) and could vary up to 10-fold between donors. Clonal patterns in blood became increasingly consistent over time, likely reflecting initial output of transient progenitors, followed by long-term HSCs with stable hierarchies. The majority of long-term clones displayed multilineage output, yet clones with lymphoid- or myeloid-biased output were also observed. Altogether, this study uncovers substantial interdonor and analysis-induced variability in the frequency of UCB CD34(+) clones that contribute to post-transplant hematopoiesis. As clone tracing is increasingly relevant, we urge for universal and transparent methods to count HSC clones during normal aging and upon transplantation. (C) 2019 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Original languageEnglish
Pages (from-to)16-25
Number of pages10
JournalBiology of Blood and Marrow Transplantation
Volume26
Issue number1
Early online date5-Sep-2019
DOIs
Publication statusPublished - Jan-2020

Keywords

  • Hematopoietic stem cells
  • Lineage tracing
  • Barcode
  • Heterogeneity
  • Umbilical cord blood
  • GENE-THERAPY
  • HUMAN HEMATOPOIESIS
  • BONE-MARROW
  • TRACKING
  • NUMBER
  • LEUKEMIA
  • ADULTS

Cite this