Large-Scale Clonal Analysis Resolves Aging of the Mouse Hematopoietic Stem Cell Compartment

Cell Stem Cell. 2018 Apr 5;22(4):600-607.e4. doi: 10.1016/j.stem.2018.03.013.

Abstract

Aging is linked to functional deterioration and hematological diseases. The hematopoietic system is maintained by hematopoietic stem cells (HSCs), and dysfunction within the HSC compartment is thought to be a key mechanism underlying age-related hematopoietic perturbations. Using single-cell transplantation assays with five blood-lineage analysis, we previously identified myeloid-restricted repopulating progenitors (MyRPs) within the phenotypic HSC compartment in young mice. Here, we determined the age-related functional changes to the HSC compartment using over 400 single-cell transplantation assays. Notably, MyRP frequency increased dramatically with age, while multipotent HSCs expanded modestly within the bone marrow. We also identified a subset of functional cells that were myeloid restricted in primary recipients but displayed multipotent (five blood-lineage) output in secondary recipients. We have termed this cell type latent-HSCs, which appear exclusive to the aged HSC compartment. These results question the traditional dogma of HSC aging and our current approaches to assay and define HSCs.

Keywords: HSC; aging; clonal analysis; hematopoiesis; hematopoietic stem cell; multipotency; self-renewal; single cell; stem cell aging.

Publication types

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

MeSH terms

  • Aging*
  • Animals
  • Hematopoietic Stem Cell Transplantation*
  • Hematopoietic Stem Cells / cytology*
  • Mice