Human CD34+ HLA-DR- bone marrow cells contain progenitor cells capable of self-renewal, multilineage differentiation, and long-term in vitro hematopoiesis.
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.
Srour
E F
EF
Department of Medicine, Indiana University School of Medicine, Indianapolis 46202-5121.
Brandt
J E
JE
Briddell
R A
RA
Leemhuis
T
T
van Besien
K
K
Hoffman
R
R
D015703:Antigens, CD / Q000032:analysis*; D018952:Antigens, CD34; D001853:Bone Marrow / Q000276:immunology / Q000502:physiology*; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D006684:HLA-DR Antigens / Q000032:analysis*; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology / Q000502:physiology*; D006801:Humans
D015703:Antigens, CD; D018952:Antigens, CD34; D006684:HLA-DR Antigens