Expression and activity of P-glycoprotein, a multidrug efflux pump, in human hematopoietic stem cells

Cell. 1991 Jul 12;66(1):85-94. doi: 10.1016/0092-8674(91)90141-k.


Hematopoietic stem cells show reduced staining with a mitochondrial fluorescent dye, rhodamine 123 (Rh-123), which was supposed to indicate decreased mitochondrial activity in these cells. Rh123 and several other fluorescent dyes are substrates for transport mediated by P-glycoprotein (P-gp), an efflux pump responsible for multidrug resistance in tumor cells. We have found that staining of human bone marrow cells with fluorescent dyes is potentiated by P-gp inhibitors and inversely correlated with P-gp expression. P-gp is expressed in practically all hematopoietic progenitor cells, including long-term culture-initiating cells. The highest levels of P-gp among the progenitors are associated with cells displaying characteristics of pluripotent stem cells. These results have implications for stem cell purification and bone marrow resistance to cancer chemotherapy.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • Bone Marrow / metabolism
  • Cells, Cultured
  • Colony-Forming Units Assay
  • Drug Resistance / physiology
  • Flow Cytometry
  • Fluorescent Antibody Technique
  • Fluorescent Dyes / metabolism
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / metabolism*
  • Humans
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Polymerase Chain Reaction
  • RNA / analysis


  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • Fluorescent Dyes
  • Membrane Glycoproteins
  • RNA