Bone marrow long label-retaining cells reside in the sinusoidal hypoxic niche

Biochem Biophys Res Commun. 2008 Feb 8;366(2):335-9. doi: 10.1016/j.bbrc.2007.11.086. Epub 2007 Nov 29.


In response to changing signals, quiescent hematopoietic stem cells (HSCs) can be induced to an activated cycling state and provide multi-lineage hematopoietic cells to the whole body via blood vessels. However, the precise localization of quiescent HSCs in bone marrow microenvironment is not fully characterized. Here, we performed whole-mount immunostaining of bone marrow and found that BrdU label-retaining cells (LRCs) definitively reside in the sinusoidal hypoxic zone distant from the "vascular niche". Although LRCs expressed very low level of a well-known HSC marker, c-kit in normal circumstances, myeloablation by 5-FU treatment caused LRCs to abundantly express c-kit and proliferate actively. These results demonstrate that bone marrow LRCs reside in the sinusoidal hypoxic niche, and function as a regenerative cell pool of HSCs.

MeSH terms

  • Animals
  • Bone Marrow Cells / cytology*
  • Cells, Cultured
  • Hematopoietic Stem Cells / cytology*
  • Mice
  • Mice, Inbred C57BL
  • Staining and Labeling / methods
  • Tibia / cytology*