Erythroid lineage-specific activity in conditioned medium derived from cloned human marrow stromal cells (CFU-RF).
Using long-term culture techniques, it has been shown that stromal cells in the marrow microenvironment are essential for the continued production and self-renewal of hematopoietic stem cells. We previously reported the development of a methylcellulose colony assay for a population of marrow stromal progenitors called CFU-RF. In this paper, a method is described for subculturing cells from individual CFU-RF-derived colonies to allow conditioned medium production (StCM). StCM, prepared in this way, was found to possess an erythroid lineage-specific activity that stimulated the formation of macroscopic erythroid colonies in cultures containing erythropoietin (epo). Using dose-response curves, the KG1 colony assay, and antibody neutralization, it was shown that the activity could not be attributed to interleukin 3 (IL3) or granulocyte-macrophage colony-stimulating factor (GM-CSF). However, it was further shown that a monolayer of stromal cells, which had earlier been producing the erythroid activity, could be stimulated by IL1 to produce granulocytic colony-stimulating activity, but only as long as IL1 was present in the culture medium. These findings indicate a mechanism whereby the same stromal population could be modulated to promote growth and differentiation of different hematopoietic lineages.
Department of Medicine, University of Ottawa, Ontario, Canada.
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Izaguirre
D001853:Bone Marrow / Q000187:drug effects; D001854:Bone Marrow Cells; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D002999:Clone Cells; D003470:Culture Media; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007377:Interleukin-3 / Q000276:immunology / Q000502:physiology; D011994:Recombinant Proteins / Q000494:pharmacology
D003470:Culture Media; D007375:Interleukin-1; D007377:Interleukin-3; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor