Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
 6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Erythropoietin (EPO) is a hematopoietic growth factor that stimulates the proliferation and differentiation of erythroid progenitor cells. Although the EPO receptor has no kinase domain, EPO rapidly induces tyrosine phosphorylation of several proteins in EPO-responsive cells. Therefore, the receptor activation by the ligand could induce tyrosine-kinase activity of unidentified cellular protein(s). Here we show that c-fps/fes proto-oncogene product (p92c-fes), nonreceptor tyrosine kinase, is tyrosine-phosphorylated on treatment with EPO in a human erythroleukemia cell line TF-1 that is responsive to granulocyte-macrophage colony-stimulating factor, interleukin-3, and EPO. In addition, the kinase activity of p92c-fes was shown to be enhanced by treatment with EPO. Therefore, p92c-fes could be implicated in a signaling pathway triggered by EPO in human EPO-responsive cells.
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PMID:Erythropoietin induces tyrosine phosphorylation and kinase activity of the c-fps/fes proto-oncogene product in human erythropoietin-responsive cells. 768 96

Oncostatin M (OM) is structurally and functionally related to a subclass of hematopoietic cytokines including leukemia-inhibitory factor (LIF), ciliary neurotrophic factor (CNTF), granulocyte colony-stimulating factor (G-CSF), and interleukin-6 (IL-6). Using human endothelial cells (HEC) as a model for cytokine regulation of hematopoietic growth factor expression, we tested OM as an inducer of colony-stimulating activity. Colony-forming cell assays supplemented with culture supernatants from OM-treated HEC contained a threefold increase in colony-forming unit granulocyte-macrophage colonies. Specific immunoassay (enzyme-linked immunosorbent assay) of culture supernatants indicated that OM treatment of HEC resulted in a dose- and time-dependent increase in the accumulation of G-CSF and granulocyte-macrophage CSF (GM-CSF) (> 28-fold). The ED50 for OM induction of G-CSF and GM-CSF protein expression was 17 and 7 pmol/L, respectively. Increased protein expression was associated with a similar increase in steady-state expression of G-CSF and GM-CSF mRNA. Furthermore, a period of 12 to 24 hours elapsed before there were measurable increases in CSF expression, suggesting that OM may stimulate CSF production through a mechanism requiring the synthesis or activation of a secondary mediating factor or pathway. These findings provide the first evidence that OM may regulate myelopoiesis by inducing the cellular expression of hematopoietic growth factors.
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PMID:Regulation of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor expression by oncostatin M. 768 88

Interleukin-3 (IL-3) regulates growth and differentiation of multipotential as well as lineage-committed progenitor cells. The human IL-3 receptor (IL-3R) consists of the alpha and common beta (beta c) subunits. The alpha subunit (IL-3R alpha) is specific for IL-3 and binds IL-3 with low affinity. In contrast, the beta c subunit does not bind any cytokine by itself, but forms a high-affinity receptor with IL-3R alpha. As the same beta c subunit also forms high-affinity receptors for IL-5 and granulocyte-macrophage colony-stimulating factor (GM-CSF) with the respective cytokine-specific alpha subunit, the expression of the alpha subunits is responsible for specificity of cytokines. To examine the expression of IL-3R alpha, we have developed a monoclonal antibody (MoAb), N3A. N3A specifically bound to cells expressing IL-3R alpha and immunoprecipitated a 75 Kd glycoprotein, which became 43 Kd on N-glycosidase digestion. N3A and an anti-beta c antibody, CRS1, were used in double color fluorescence-activated cell sorter (FACS) staining with several lineage markers to see the IL-3R expression pattern in peripheral blood (PB), cord blood (CB), and bone marrow (BM) cells. Both IL-3R subunits were expressed on myeloid cell lineages (CD13+, CD14+, CD15Lo, or CD33+). To further study the IL-3R expression on hematopoietic progenitor cells, the CD34+ populations were isolated from both BM and CB cells. Those populations showed positive staining profiles with the N3A MoAb and were weakly stained with the CRS1 MoAb. Furthermore, anti c-kit antibody staining of the CD34+ fraction from CB, but not from BM, showed two intensities and the IL-3R alpha expression seemed to be higher in a fraction of low c-kit expression. Because IL-1, IL-6, G-CSF, stem cell factor (SCF), interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha are known to enhance IL-3-dependent colony formation, we have examined whether this enhancement could be correlated with upregulation of the IL-3R expression. Incubation of CD34+ cells with TNF-alpha for 2 days significantly increased the level of beta c and G-CSF increased the number of cells with high level expression of alpha, while other factors did not affect the IL-3R expression. Thus, different cytokines appear to have different mechanisms for enhancement of IL-3-dependent proliferation.
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PMID:Expression and factor-dependent modulation of the interleukin-3 receptor subunits on human hematopoietic cells. 768 90

Interleukin 3 (IL-3) is a hematopoietic growth factor with a pronounced thrombopoietic activity as well as a broad spectrum of activities on multipotent, committed and mature cells of different lineages. Available for clinical trials since 1989, IL-3 has been used in well over two thousand patients. In numerous phase I-II clinical trials, the tolerability profile and the various biologic activities have been defined, and ongoing phase III trials will finally establish its clinical relevance. Doses between 2.5 and 10 micrograms/kg/d given subcutaneously are well tolerated, cause low grade fever, occasional flu-like symptoms and headache. At these doses IL-3 enhances platelet and neutrophil recovery after cycles of myelotoxic chemotherapy, resulting in better adherence to the planned chemotherapy doses and schedules and a decrease in the need for platelet transfusions. Accelerated engraftment of platelets and neutrophils is seen with IL-3 also after bone marrow transplantation. The effect on neutrophil recovery can be enhanced by the use of a myeloid growth factor such as granulocyte-macrophage colony-stimulating factor (GM-CSF) or granulocyte (G)-CSF after five to 10 days of IL-3. Treatment enhancement is related to the effect of IL-3 on the proliferation of hematopoietic progenitors, which leads to an increase in target cells for GM- or G-CSF. Because of the increase in bone marrow proliferation, IL-3 is being used to increase the mobilization of progenitor cells to the blood and in bone marrow failure.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Present and future clinical relevance of interleukin 3. 769 63

The effects of various cytokines on MHC class II antigen expression were examined in murine microglia. Interleukin-3 (IL-3), as well as interferon-gamma (IFN-gamma), induced MHC class II antigen expression on these cells. IL-3 additionally enhanced MHC class II antigen expression induced by IFN-gamma. The induction of MHC class II antigen expression by IL-3 was not mediated via IFN-gamma production, because the effect was not blocked by antibodies to IFN-gamma. In contrast, granulocyte-macrophage colony-stimulating factor (GM-CSF) did not affect the expression of MHC class II antigen on naive cells and down-regulated IFN-gamma-mediated induction of MHC class II antigen expression on microglia. Because IL-3 and GM-CSF are apparently produced in the central nervous system, MHC class II antigen expression on microglia may be regulated by these cytokines synthesized in the central nervous system.
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PMID:Induction of MHC class II antigen expression on murine microglia by interleukin-3. 782 62

Interleukin (IL)-3-like bioactivity has been found in culture supernatants from human and murine keratinocytes. However, there is controversy as to the presence of IL-3 mRNA in human keratinocytes. Using highly sensitive reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay techniques, we examined human keratinocytes from four different donors (neonatal foreskins) and were unable to detect IL-3 mRNA or IL-3 protein. Despite successful amplification of DNA from an IL-3 cDNA, no product could be obtained by amplification of keratinocyte RNA treated with reverse transcription-polymerase chain reaction. Analysis of concentrated (up to 50-fold) supernatants failed to detect IL-3 protein by enzyme-linked immunosorbent assay. Because ultraviolet radiation up-regulates many cytokines, we irradiated human keratinocytes with 300 J/m2 ultraviolet B and collected supernatants 24 h post-irradiation. Supernatants concentrated 50-fold were also negative for IL-3 protein by enzyme-linked immunosorbent assay. When assayed on the IL-3-responsive M-07e cell line, unirradiated supernatants stimulated M-07e proliferation 22-fold over background levels. Irradiated supernatants stimulated M-07e proliferation 128-fold. Neither the unirradiated nor the irradiated supernatant activity could be neutralized with antibody to human IL-3. However, incubation of irradiated supernatants with antibody to granulocyte macrophage-colony-stimulating factor (GM-CSF) reduced the M-07e proliferation by 90%. Antibodies against GM-CSF and IL-6 completely abrogated proliferation. Reverse transcription-polymerase chain reaction confirmed a concomitant elevation of IL-6 (2.6- to 5.6-fold) and of GM-CSF mRNA (2.7- to 4.3-fold) at 6 and 24 h after ultraviolet B irradiation in keratinocytes, but no IL-3 amplification products could be detected. IL-3 mRNA was also not detected in adult keratinocytes. Even after stimulation by IL-1 alpha, tumor necrosis factor-alpha, or phobol myristate acetate, IL-3 mRNA was not detected in either neonatal or adult human keratinocytes. We have been unable to detect IL-3 mRNA or IL-3 protein in human keratinocytes. The IL-3-like activity in human keratinocytes is mainly due to GM-CSF, with a small contribution from IL-6.
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PMID:Failure to detect interleukin (IL)-3 mRNA or protein in human keratinocytes: antibodies to granulocyte macrophage-colony-stimulating factor or IL-6 (but not IL-3) neutralize "IL-3" bioactivity. 786 Sep 97

Apoptosis (programmed cell death) regulates cell population size. To determine the mechanisms whereby hematopoietic growth factors (HGFs) modulate apoptosis in human myeloid leukemic cells, we evaluated the roles of protein and mRNA synthesis for altering apoptosis in growth factor-stimulated vs. quiescent leukemic TF1 cells. Lysates of cells from the granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent myeloid leukemic cell line TF1 were separated into high molecular weight (HMW) pellets of intact DNA and supernatants of fragmented low MW (LMW) DNA, and the DNA purified from these fractions was quantified. In the absence of both GM-CSF and fetal bovine serum (FBS), 70% of the DNA was fragmented after 3 days in culture, with a characteristic apoptotic ladder-like pattern on agarose gel electrophoresis, whereas this proportion had initially been < 5%. In contrast, less than 5% of the DNA was fragmented in cells incubated with GM-CSF plus FBS or GM-CSF alone. Delayed addition of GM-CSF, but not FBS, permitted partial rescue of the cells, inhibiting increasing rates of accumulation of fragmented DNA. When the macro-molecular synthesis inhibitor cycloheximide (CHX) or actinomycin D (Act D) was present for 26 hours in the absence of GM-CSF and FBS, apoptosis was inhibited. In contrast, in the presence of GM-CSF or FBS, apoptosis was enhanced upon addition of CHX or Act D. The latter effect persisted even with the late addition of CHX. These findings indicate that disparate mechanisms of enhancing or inhibiting apoptosis exist in myeloid leukemic cells related to environmental conditions, including HGF-regulated cellular synthesis of distinct proteins and mRNA.
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PMID:Modulation of apoptosis in human myeloid leukemic cells by GM-CSF. 787 43

Taxol, a microtubule-stabilizing agent, has been shown to have antineoplastic activity against various tumors. In addition, it has been shown that taxol resembles bacterial lipopolysaccharide in its ability to activate macrophages. Recently we have shown that lipopolysaccharide induces the expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) in murine B-cell lines. In light of the similarity of taxol and lipopolysaccharide in their effects on macrophages, we tested whether taxol could also induce the expression of GM-CSF in B-cell lines. In the present study we used the murine B-lymphoma cell line M12.4.1. In unstimulated cells, no GM-CSF mRNA was detected, whereas in taxol-stimulated stimulated cells at a concentration of 30 microM, GM-CSF mRNA was induced 4-8 h after stimulation. This induction of GM-CSF mRNA was down-regulated by 10 ng/ml of interleukin 4. Actinomycin D chase experiments revealed that interleukin 4 did not affect the half-life of the taxol-induced GM-CSF cytoplasmic mRNA, nor did it alter GM-CSF gene transcription. Polymerase chain reaction analysis of nuclear RNA, utilizing probes specific for sequences in the first intron of GM-CSF, indicated that taxol enhances accumulation of nuclear precursor RNA and that interleukin 4 decreases this accumulation. The present study shows a novel activity of taxol in inducing the release of the hematopoietic growth factor GM-CSF from B-cells. Since GM-CSF is known to recruit macrophages and enhance their cytotoxicity against tumor cells, our observations suggest that part of the known antitumor activity of taxol may be due to synergistic effects of GM-CSF activity together with direct cytotoxic actions through microtubule stabilization.
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PMID:Taxol induces the hematopoietic growth factor granulocyte-macrophage colony-stimulating factor in murine B-cells by stabilization of granulocyte-macrophage colony-stimulating factor nuclear RNA. 791 12

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic growth factor that stimulates the proliferation, maturation, and functional activity of myeloid cells in peripheral blood and bone marrow. Expression of GM-CSF is tightly regulated and is limited to cells stimulated directly (T cells, macrophages) or indirectly (fibroblasts, endothelial cells) by immune challenge. Several studies of the transcriptional control of GM-CSF expression have elucidated a region of the GM-CSF promoter that mediates positive regulatory activity in a number of cell types. This region contains a direct repeat of the sequence CATTA/T that extends from nucleotides -37 to -48 upstream of the start of mRNA synthesis. Although specific DNA:protein interactions have been shown within this region, neither the nature nor the number of nuclear factors responsible for these interactions have been characterized. In this study, we use DNase I footprinting analysis to demonstrate that point mutations, which inactivate the GM-CSF promoter, disrupt DNA:protein interactions within this region. By combined electrophoretic mobility shift and ultraviolet cross-linking analysis, we have detected several protein species that bind specifically to the positive regulatory sequence.
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PMID:Characterization of nuclear factors that bind to a critical positive regulatory element of the human granulocyte-macrophage colony-stimulating factor promoter. 791 70

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic growth factor known to promote the proliferation and differentiation of precursors of granulocytes and monocytes. GM-CSF at standard doses (125-500 micrograms/m2) alleviates neutropenia secondary to cytotoxic chemotherapy, myelodysplastic syndromes, and aplastic anemia, but has minimal effect on anemia or thrombocytopenia. GM-CSF at doses < 30 micrograms/m2 has been reported to improve platelet counts in some patients exhibiting cytopenia related to hematologic disorders such as aplastic anemia and myelodysplastic syndrome. Low-dose GM-CSF (10-20 micrograms/m2) was evaluated in 20 patients with transfusion-dependent thrombocytopenia persisting after myeloablative cytotoxic chemotherapy or with disease-related cytopenia. Seven patients (35%) responded as defined by a reduction in the platelet transfusion requirements by at least 75%. Low-dose GM-CSF did not significantly increase neutrophil counts or decrease red blood cell transfusion requirements. These results indicate that low-dose GM-CSF has a thrombopoietic effect in about one-third of patients with platelet transfusion-dependent thrombocytopenia which has not been observed at higher doses.
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PMID:Effect of low-dose granulocyte-macrophage colony-stimulating factor (LD-GM-CSF) on platelet transfusion-dependent thrombocytopenia. 794 85


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