Environmental Optimization Enables Maintenance of Quiescent Hematopoietic Stem Cells Ex Vivo

Cell Rep. 2019 Jul 2;28(1):145-158.e9. doi: 10.1016/j.celrep.2019.06.008.

Abstract

Hematopoietic stem cells (HSCs) maintain lifelong hematopoiesis by remaining quiescent in the bone marrow niche. Recapitulation of a quiescent state in culture has not been achieved, as cells rapidly proliferate and differentiate in vitro. After exhaustive analysis of different environmental factor combinations and concentrations as a way to mimic physiological conditions, we were able to maintain engraftable quiescent HSCs for 1 month in culture under very low cytokine concentrations, hypoxia, and very high fatty acid levels. Exogenous fatty acids were required likely due to suppression of intrinsic fatty acid synthesis by hypoxia and low cytokine conditions. By contrast, high cytokine concentrations or normoxia induced HSC proliferation and differentiation. Our culture system provides a means to evaluate properties of steady-state HSCs and test effects of defined factors in vitro under near-physiological conditions.

Keywords: fatty acid; hematopoietic stem cell; hypoxia; quiescence; stem cell culture; stem cell metabolism; stem cell niche.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Bone Marrow / metabolism
  • Bone Marrow Cells / cytology
  • Bone Marrow Cells / metabolism
  • Cell Culture Techniques / methods*
  • Cell Hypoxia / physiology
  • Cell Proliferation / drug effects
  • Cell Proliferation / physiology
  • Cholesterol / pharmacology
  • Cytokines / pharmacology*
  • Fatty Acids / pharmacology*
  • Gene Ontology
  • Hematopoiesis / drug effects*
  • Hematopoiesis / physiology
  • Hematopoietic Stem Cells / cytology*
  • Hematopoietic Stem Cells / drug effects*
  • Hematopoietic Stem Cells / metabolism
  • Humans
  • Insulin / pharmacology
  • Mice
  • Mice, Inbred C57BL
  • Oligonucleotide Array Sequence Analysis
  • Single-Cell Analysis
  • Stem Cell Factor / pharmacology
  • Stem Cell Niche / drug effects
  • Stem Cell Niche / physiology

Substances

  • Cytokines
  • Fatty Acids
  • Insulin
  • Stem Cell Factor
  • Cholesterol