Hematopoietic stem cell arrival triggers dynamic remodeling of the perivascular niche

Cell. 2015 Jan 15;160(1-2):241-52. doi: 10.1016/j.cell.2014.12.032.

Abstract

Hematopoietic stem and progenitor cells (HSPCs) can reconstitute and sustain the entire blood system. We generated a highly specific transgenic reporter of HSPCs in zebrafish. This allowed us to perform high-resolution live imaging on endogenous HSPCs not currently possible in mammalian bone marrow. Using this system, we have uncovered distinct interactions between single HSPCs and their niche. When an HSPC arrives in the perivascular niche, a group of endothelial cells remodel to form a surrounding pocket. This structure appears conserved in mouse fetal liver. Correlative light and electron microscopy revealed that endothelial cells surround a single HSPC attached to a single mesenchymal stromal cell. Live imaging showed that mesenchymal stromal cells anchor HSPCs and orient their divisions. A chemical genetic screen found that the compound lycorine promotes HSPC-niche interactions during development and ultimately expands the stem cell pool into adulthood. Our studies provide evidence for dynamic niche interactions upon stem cell colonization. PAPERFLICK:

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Cell Division
  • Core Binding Factor alpha Subunits / genetics
  • Core Binding Factor alpha Subunits / metabolism
  • Embryo, Nonmammalian / blood supply
  • Embryo, Nonmammalian / physiology
  • Endothelium / cytology
  • Endothelium / physiology*
  • Hematopoietic Stem Cells / cytology*
  • Hematopoietic Stem Cells / physiology
  • Mesoderm / cytology
  • Mesoderm / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Stem Cell Niche
  • Stromal Cells / cytology
  • Stromal Cells / metabolism
  • Zebrafish / embryology*
  • Zebrafish / physiology

Substances

  • Core Binding Factor alpha Subunits

Associated data

  • GEO/GSE56015