title: Enhancement of colony-forming activity of granulocyte-macrophage colony-stimulating factor by monocytes in vitro.
abstract: Human recombinant granulocyte-macrophage colony-stimulating factor (hrGM-CSF) stimulated granulocyte-macrophage (GM) colony formation from human marrow mononuclear cells (MMCs) in a dose-dependent manner in methylcellulose culture. When phagocytes were depleted from MMCs, GM colony formation from the phagocyte-depleted (PD) MMCs by hrGM-CSF markedly decreased. Experiments in which PD-MMCs were cultured with hrGM-CSF and adherent cells showed that 94% (on day 7 and day 14) of the colonies from PD-MMCs were dependent on the presence of adherent cells. In contrast, the ability of granulocyte colony-stimulating factor (G-CSF) to form colonies was not affected by phagocyte depletion. To check for the presence or absence of progenitors that could form GM colonies in direct response to hrGM-CSF, single-cell culture of hematopoietic progenitor cell surface antigen (My-10)-positive PD-MMCs was carried out using a flow cytometer and an Autoclone System. In duplicate experiments, 0.7% and 3.5% (day 7) or 3.6% and 3.9% (day 14) of My-10-positive PD-MMCs formed GM colonies in response to hrGM-CSF and 5.1% and 6.0% (day 7) of My-10-positive PD-MMCs formed GM colonies in response to G-CSF. This was clear evidence for the presence of progenitors directly responding to hrGM-CSF. Also observed was a synergistic effect on GM colony formation in which more My-10-positive PD-MMCs stimulated by hrGM-CSF and G-CSF could form GM colonies than the sum of those stimulated by each separately. This enhancing effect of colony-forming activity of hrGM-CSF by adherent cells and the single cell culture experiment were reproduced in serum-free culture system.
authors.affiliation: Division of Blood Transfusion, Hyogo College of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Namiki
authors.forename: H
authors.initials: H
authors.lastname: Hara
mesh_terms: D000954:Antigens, Surface; D001853:Bone Marrow / Q000502:physiology; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D003470:Culture Media; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006133:Growth Substances / Q000494:pharmacology*; D006410:Hematopoiesis / Q000187:drug effects; D006412:Hematopoietic Stem Cells / Q000145:classification / Q000276:immunology / Q000502:physiology*; D006801:Humans; D008562:Membrane Glycoproteins; D009000:Monocytes / Q000145:classification / Q000502:physiology*; D010641:Phenotype; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D000954:Antigens, Surface; D003115:Colony-Stimulating Factors; D003470:Culture Media; D006133:Growth Substances; D008562:Membrane Glycoproteins; C050120:My-10 glycoprotein; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor