Human CD34+ HLA-DR- bone marrow cells contain progenitor cells capable of self-renewal, multilineage differentiation, and long-term in vitro hematopoiesis

Blood Cells. 1991;17(2):287-95.


Human bone marrow cells expressing CD34 but not HLA-DR were isolated by immunofluorescence flow cytometric cell sorting. These cells contained a hematopoietic cell (CFU-B1) capable of producing, in an in vitro semisolid culture system, blast-cell-containing colonies, which possessed the capacity for self-renewal and commitment to multipotential differentiation. In addition, CD34+ HLA-DR- marrow cells contained primitive megakaryocyte progenitor cells, the burst-forming unit-megakaryocyte (BFU-MK). A subset of CD34+ HLA-DR- marrow cells lacking the expression of CD15 and CD71 was obtained by flow cytometric cell sorting and was capable of sustaining in vitro hematopoiesis in suspension culture for up to 8 weeks in the absence of a preestablished adherent marrow cell layer. The combination of IL-3 + IL-1 alpha and IL-3 + IL-6 sustained proliferation of these cells for 8 weeks, induced maximal cellular expansion, and increased the numbers of assayable progenitor cells. These studies demonstrate that human CD34+ HLA-DR- marrow cells and their subsets contain primitive multipotential hematopoietic cells capable of self-renewal and of differentiation into multiple hematopoietic lineages.

Publication types

  • Review

MeSH terms

  • Antigens, CD / analysis*
  • Antigens, CD34
  • Bone Marrow / immunology
  • Bone Marrow / physiology*
  • Cell Differentiation
  • Cell Division
  • Cells, Cultured
  • HLA-DR Antigens / analysis*
  • Hematopoiesis*
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / immunology
  • Hematopoietic Stem Cells / physiology*
  • Humans


  • Antigens, CD
  • Antigens, CD34
  • HLA-DR Antigens