Functional activity of murine CD34+ and CD34- hematopoietic stem cell populations

Exp Hematol. 1999 May;27(5):788-96. doi: 10.1016/s0301-472x(99)00032-6.


The transmembrane glycoprotein CD34 is expressed on human hematopoietic stem cells and committed progenitors in the bone marrow, and CD34-positive selection currently is used to isolate bone marrow repopulating cells in clinical transplantation protocols. Recently, CD34- hematopoietic stem cells were described in both humans and mice, and it was suggested that CD34+ murine bone marrow cells may lack long-term reconstituting ability. In this study, the long-term repopulating ability of CD34+Lin- vs CD34-Lin- cells was compared directly using syngeneic murine bone marrow transplantation. Highly purified populations of CD34+Lin- and CD34-Lin- cells each are able to reconstitute bone marrow, confirming that both populations contain hematopoietic stem cells; however, the number of hematopoietic stem cells in the CD34+Lin- fraction is approximately 100-fold greater than the number in the CD34-Lin- fraction. In competitive repopulation experiments, CD34+ stem cells are better able to engraft the bone marrow than are CD34- cells. CD34+Lin- cells provide both short- and long-term engraftment, but the CD34-Lin- cells are capable of only long-term engraftment. Ex vivo, the CD34+Lin- stem cells expand over 3 days in culture and maintain the ability to durably engraft animals in a serial transplant model. In contrast, when CD34-Lin- cells are cultured using the same conditions ex vivo, the cell number decreases, and the cells do not retain the ability to repopulate the bone marrow. Thus, the CD34+Lin- and CD34-Lin- cells constitute two functionally distinct populations that are capable of long-term bone marrow reconstitution.

Publication types

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

MeSH terms

  • Animals
  • Base Sequence
  • CD4 Antigens / analysis*
  • CD4 Antigens / genetics
  • Cell Separation
  • DNA Primers
  • Female
  • Flow Cytometry
  • Hematopoietic Stem Cells / cytology*
  • Hematopoietic Stem Cells / immunology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred DBA
  • RNA, Messenger / genetics


  • CD4 Antigens
  • DNA Primers
  • RNA, Messenger