The neurotrophic factor receptor RET drives haematopoietic stem cell survival and function

Nature. 2014 Oct 2;514(7520):98-101. doi: 10.1038/nature13498. Epub 2014 Jul 27.

Abstract

Haematopoiesis is a developmental cascade that generates all blood cell lineages in health and disease. This process relies on quiescent haematopoietic stem cells capable of differentiating, self renewing and expanding upon physiological demand. However, the mechanisms that regulate haematopoietic stem cell homeostasis and function remain largely unknown. Here we show that the neurotrophic factor receptor RET (rearranged during transfection) drives haematopoietic stem cell survival, expansion and function. We find that haematopoietic stem cells express RET and that its neurotrophic factor partners are produced in the haematopoietic stem cell environment. Ablation of Ret leads to impaired survival and reduced numbers of haematopoietic stem cells with normal differentiation potential, but loss of cell-autonomous stress response and reconstitution potential. Strikingly, RET signals provide haematopoietic stem cells with critical Bcl2 and Bcl2l1 surviving cues, downstream of p38 mitogen-activated protein (MAP) kinase and cyclic-AMP-response element binding protein (CREB) activation. Accordingly, enforced expression of RET downstream targets, Bcl2 or Bcl2l1, is sufficient to restore the activity of Ret null progenitors in vivo. Activation of RET results in improved haematopoietic stem cell survival, expansion and in vivo transplantation efficiency. Remarkably, human cord-blood progenitor expansion and transplantation is also improved by neurotrophic factors, opening the way for exploration of RET agonists in human haematopoietic stem cell transplantation. Our work shows that neurotrophic factors are novel components of the haematopoietic stem cell microenvironment, revealing that haematopoietic stem cells and neurons are regulated by similar signals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Survival
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Enzyme Activation
  • Female
  • Hematopoiesis
  • Hematopoietic Stem Cell Transplantation
  • Hematopoietic Stem Cells / cytology*
  • Hematopoietic Stem Cells / metabolism*
  • Humans
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Nerve Growth Factors / metabolism*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Proto-Oncogene Proteins c-ret / deficiency
  • Proto-Oncogene Proteins c-ret / genetics
  • Proto-Oncogene Proteins c-ret / metabolism*
  • Signal Transduction
  • Stem Cell Niche
  • bcl-X Protein / metabolism
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • BCL2L1 protein, human
  • Bcl2l1 protein, mouse
  • Cyclic AMP Response Element-Binding Protein
  • Nerve Growth Factors
  • Proto-Oncogene Proteins c-bcl-2
  • bcl-X Protein
  • Proto-Oncogene Proteins c-ret
  • RET protein, human
  • Ret protein, mouse
  • p38 Mitogen-Activated Protein Kinases