Regulation of the differentiation of WEHI-3B D+ leukemia cells by granulocyte colony-stimulating factor receptor

• Published in: The Journal of cell biology 1993-03, Vol.120 (6), p.1481-1489
• Main Authors: JIANMING LI, KOAY, D. C, HONG XIAO, SARTORELLI, A. C
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Blotting, Northern; Cadmium - pharmacology; Cadmium Chloride; Cell Differentiation; Cell differentiation, maturation, development, hematopoiesis; Cell Division - drug effects; Cell physiology; Cellular biology; Chlorides - pharmacology; Cross-Linking Reagents; Fundamental and applied biological sciences. Psychology; Granulocyte Colony-Stimulating Factor - metabolism; Granulocyte Colony-Stimulating Factor - pharmacology; Humans; Leukemia; Leukemia, Experimental; Mice; Molecular and cellular biology; Plasmids; Receptors, Granulocyte Colony-Stimulating Factor - genetics; Receptors, Granulocyte Colony-Stimulating Factor - physiology; Recombinant Proteins - metabolism; Recombinant Proteins - pharmacology; RNA, Messenger - metabolism; Transfection; Tretinoin - pharmacology; Tumor Cells, Cultured
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.120.6.1481

To investigate the role of the G-CSF receptor (G-CSFR) in mediating the action of G-CSF, WEHI-3B D+ murine myelomonocytic leukemia cells were transfected with a plasmid containing the murine G-CSFR gene. Overexpression of G-CSFR in transfected clones was demonstrated by northern blotting, binding of [125I]rhG-CSF and cross-linking experiments. A high level of expression of the G-CSFR did not promote or suppress cellular proliferation or initiate differentiation; however, exposure of transfected cells to G-CSF in suspension culture caused a large percentage of the population to enter a differentiation pathway, as determined by two markers of the mature state, the ability of cells to reduce nitroblue tetrazolium (NBT) and to express the differentiation antigen Mac-1 (CD11b) on the cell surface. Thus, upon treatment with 10 ng/ml of G-CSF, 60% or more of transfected cells exhibited NBT positivity; whereas, in contrast, nontransfected cells exhibited only 6% NBT positivity in response to G-CSF. An eightfold increase in Mac-1 expression over that of the parental line was also observed in transfected cells exposed to G-CSF. The growth rate of the transfected clones was decreased by exposure to G-CSF, presumably due to terminal differentiation. The findings suggest that the predominant function of G-CSF and its receptor in WEHI-3B D+ cells is to mediate differentiation and that the level of the G-CSFR portion of the signal transduction mechanism in this malignant cell line is important for a response to the maturation inducing function of the cytokine.