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

The in vitro growth of early (megakaryocyte burst-forming units, BFU-meg) and late (megakaryocyte colony-forming units, CFU-meg) megakaryocyte (meg) progenitors has been evaluated in normal adult human peripheral blood (PB). All the experiments were carried out using CD34+ cells, which were assayed in a serum-free fibrinclot assay. PB BFU-meg were morphologically characterized as plurifocal aggregates containing greater than 50 cells/colony, distinct from unifocal CFU-meg, in a limiting dilution assay. At variance with PB CFU-meg, PB BFU-meg were unaffected by the complement-mediated cytotoxicity with anti-HLA-DR. The optimal source of colony-stimulating activity for PB BFU-meg growth was recombinant human interleukin 3 (rhIL-3; 100 U/ml), which supported a significantly higher number of BFU-meg in comparison with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 200 U/ml, p = 0.043). Combinations of rhIL-3 (100 U/ml) plus rhGM-CSF (200 U/ml), rhIL-3 plus recombinant human interleukin 6 (rhIL-6; 100 U plus 100 U/ml) or rhIL-3 plus rhGM-CSF plus rhIL-6 (100 U plus 200 U/ml plus 100 U/ml) failed to further increase the number of PB BFU-meg with respect to rhIL-3 (100 U/ml) alone. Both PB BFU-meg and CFU-meg were markedly inhibited, in a dose-dependent fashion, by increasing doses of human purified transforming growth factor-beta 1 (TGF-beta 1) (from 0.001 to 10 ng/ml). Finally, the CFU-meg/BFU-meg ratio in PB (0.52) was significantly different from that of normal bone marrow (2.3), clearly indicating that adult human peripheral blood predominantly carries primitive megakaryocytic progenitors.
...
PMID:Prevalence of the primitive megakaryocyte progenitors (BFU-meg) in adult human peripheral blood. 137 7

Purified natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID) to ascertain their effect on hematopoiesis. When activated and propagated with recombinant human interleukin-2 (rhIL-2) in vitro, SCID spleen cells maintained a phenotypic and lytic spectrum consistent with a pure population of activated NK cells. When added with syngeneic bone marrow cells (BMC) in soft agar, the activated NK cells could support hematopoietic growth in vitro without the addition of exogenous hematopoietic growth factors. However, when syngeneic BMC were added along with cytokines to produce optimal growth conditions, the addition of NK cells was then inhibitory for hematopoietic colony formation. Antibodies to interferon-gamma (IFN-gamma) partially reversed the inhibitory effects. Supernatants from the NK-cell cultures could also exert these effects on hematopoiesis, although to a lesser extent. Analysis of the NK cell RNA demonstrated that activated NK cells express genes for hematopoietic growth factors such as granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte CSF (G-CSF), and IL-1 beta. The NK cells were also found to express IFN-gamma, transforming growth factor-beta 1 (TGF-beta 1), and tumor necrosis factor-alpha (TNF-alpha) mRNA. Analysis of the NK-cell supernatants using factor-dependent myeloid progenitor cell lines showed that the NK cells were producing G-CSF and growth-promoting activity that could not be attributed to IL-1, IL-3, IL-4, IL-5, IL-6, GM-CSF, G-CSF, macrophage CSF (M-CSF), or stem cell factor. The transfer of activated NK cells with BMC into lethally irradiated syngeneic mice resulted in greater BMC engraftment in the recipients. Thus, these results using a pure population of activated NK cells indicate that when activated, these cells can produce a variety of growth factors for hematopoiesis and exert significant hematopoietic growth-promoting effects in vivo.
...
PMID:Interleukin-2-activated natural killer cells can support hematopoiesis in vitro and promote marrow engraftment in vivo. 137 86

Cytokine release at the cartilage/pannus junction (CPJ) may be involved in cartilage destruction and tissue repair in rheumatoid arthritis (RA). Tissue samples of CPJ from 12 RA patients were examined for the presence of cytokines using immunohistochemical techniques with immunoaffinity purified F(ab')2 antibodies raised against recombinant human cytokines. Twenty-four areas of distinct CPJ at which a discrete junction between cartilage and overlying pannus exists were observed. In all specimens, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1 alpha. IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF) and transforming growth factor (TGF)-beta 1 were detected in cells in pannus particularly along the surface of cartilage and at the site of cartilage erosion. Double immunofluorescence staining showed that most cytokine containing cells also labelled with a macrophage marker (CD68). About 50% of blood vessel endothelial cells stained for GM-CSF. Twelve areas of diffuse fibroblastic CPJ, at which an indistinct margin is seen between cartilage and pannus were examined. At this site, TGF-beta 1 was the only cytokine detected in fibroblast-like cells. None of these cytokines were detected in synovial tissue at the normal synovium/cartilage junction. Chondrocytes from all 11 normal specimens as well as those from RA patients stained for IL-1 alpha, TNF-alpha, IL-6, GM-CSF and TGF-beta 1, especially those close to subchondral bone. However, IL-1 beta, interferon-gamma and lymphotoxin were not detected in either the normal synovium/cartilage junction or rheumatoid CPJ.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Detection of cytokines at the cartilage/pannus junction in patients with rheumatoid arthritis: implications for the role of cytokines in cartilage destruction and repair. 139 70

Interleukin 6 (IL-6) and leukaemia inhibitory factor (LIF) can have pleiotropic effects on different cell types. M1 myeloid leukaemic cells respond to IL-6 with activation of a terminal differentiation programme which includes activation of genes for certain haemopoietic regulatory proteins (IL-6, IL-1 alpha, IL-1 beta, granulocyte-macrophage colony-stimulating factor [GM-CSF], M-CSF, tumour necrosis factor and transforming growth factor [TGF] beta 1) and for receptors for some of these proteins, thus establishing a network of positive and negative regulatory cytokines. IL-6 and some other cytokines also induce during differentiation sustained levels of transcription factors that can regulate and maintain gene expression in the differentiation programme. M1 leukaemic cells induced to differentiate with IL-6 undergo programmed cell death (apoptosis) on withdrawal of IL-6, and can be rescued from apoptosis by IL-6, IL-3, M-CSF, G-CSF or IL-1, but not by GM-CSF. These differentiating leukaemic cells can also be rescued from apoptosis by the tumour promoter TPA (12-O-tetradecanoylphorbol-13-acetate) but not by the non-tumour-promoting isomer 4-alpha-TPA, and rescue from apoptosis can be achieved by different pathways. Apoptosis can also be induced in undifferentiated M1 leukaemic cells by expression of the wild-type form of the tumour suppressor p53 protein and IL-6 can rescue the cells from this wild-type p53-mediated apoptosis. There are clones of M1 cells that differentiate with IL-6 but not with LIF and another M1 clone that differentiates with either IL-6 or LIF. Differentiation induced by IL-6 or LIF is inhibited by TGF-beta 1. The pleiotropic effects of LIF, like those of IL-6, are presumably also in a network of interacting regulatory proteins.
...
PMID:Regulation of leukaemic cells by interleukin 6 and leukaemia inhibitory factor. 142 20

Experiments were undertaken to investigate the molecular basis of primitive hematopoietic progenitor cell regulation in both the long-term culture system and in methylcellulose, particularly with a view to characterizing factors either able or unable to influence the behaviour of primitive leukemic cells from patients with chronic myeloid leukemia (CML). Long-term cultures of CML cells with or without irradiated normal marrow feeder layers were initiated from peripheral blood cells of CML patients with high white blood cell counts. Three weeks later the effect of exogenously added transforming growth factor-beta 1 (TGF-beta 1) on progenitor cycling status was examined. A single addition of 5 ng/ml TGF-beta 1 was able to reversibly arrest the otherwise uninterrupted turnover of primitive leukemic erythroid and granulopoietic progenitors for a period of up to 7 days both in the presence and absence of a normal adherent cell population. When TGF-beta 1 was incorporated into methylcellulose cultures, its ability to inhibit colony formation by CML progenitors showed the same differential activity on primitive cell types exhibited by normal progenitors. Dose-response curves for analogous populations of normal and leukemic cells were indistinguishable. Increasing the concentration of granulocyte-macrophage colony-stimulating factor (GM-CSF) in methylcellulose colony assays decreased the sensitivity displayed by normal clonogenic cells to TGF-beta 1 and no differences were detectable when CML cells were used in such regulator competition experiments. These findings support a general model of primitive hematopoietic cell regulation in which entry into S-phase is determined at the intracellular level by multiple convergent pathways that may deliver either positive or negative signals from activated cell surface receptors for distinct extracellular factors. The present study shows for the first time that primitive CML progenitors exposed to TGF-beta 1 in vitro can be transiently blocked in a noncycling state for several days without loss of viability and that the mechanisms responsible for the emergence and maintenance of a clonal population of CML cells in vivo do not appear to involve changes in their sensitivity to TGF-beta 1. It is thus unlikely that the heightened proliferative activity exhibited by primitive CML progenitors both in vivo and in long-term culture can be explained by an abnormality in the intracellular mechanisms normally activated by TGF-beta 1 receptor-ligand binding. We suggest that primitive CML cells are either defective in their ability to see (or activate) endogenously produced TGF-beta 1, or are defective in their responsiveness to another, undefined, regulator.
...
PMID:Granulocyte-macrophage colony-stimulating factor modulation of the inhibitory effect of transforming growth factor-beta on normal and leukemic human hematopoietic progenitor cells. 151 2

Effects of cytokines on murine megakaryocyte (MK) colony formation from either unfractionated marrow cells or purified early haematopoietic cells were studied. Recombinant interleukin-3 (IL3), interleukin-6 (IL6), granulocyte-macrophage colony-stimulating factor (GM-CSF), erythropoietin (Epo) and acidic and basic fibroblast growth factor (aFGF and bFGF) each was able to stimulate MK colony growth although they varied somewhat in their potential. IL6 and FGFs, in addition to their effect on MK colony growth, increased the size of individual MK. The combination of IL3 with IL6 or FGF resulted in an additive action. Monoclonal anti-IL6 antibody completely neutralized the activity of mouse IL6 and FGFs but had no effect on human IL6, mouse IL3 and GM-CSF. When using purified lineage negative marrow cells, only IL3 and IL6 promoted MK colony formation. Transforming growth factor beta 1 (TGF-beta 1) at 10-200 pg/ml selectively inhibited IL3-induced MK colony formation, and at 0.2-0.5 ng/ml it still had no obvious effect on the activity of IL6 or GM-CSF but caused an inhibition of FGF-induced MK colony formation. These data suggest that differential mechanisms are involved in the regulation of megakaryocytopoiesis by IL3, IL6, FGFs and GM-CSF, and that TGF-beta 1 negatively regulates MK development mainly by interfering with the action of IL3.
...
PMID:New insights into the regulation of megakaryocytopoiesis by haematopoietic and fibroblastic growth factors and transforming growth factor beta 1. 152 Jun 6

Exposure of human polymorphonuclear neutrophils to phorbol 12-myristate 13-acetate (PMA) results in a 70-75% reduction in the specific binding of 125I-granulocyte-macrophage colony-stimulating factor (GM-CSF) to its receptors. The PMA-induced reduction in 125I-GM-CSF binding is due to a decrease in the number of available GM-CSF receptors, as derived from Scatchard analysis of the binding data. On the other hand, the phorbol ester 4-alpha-phorbol 12,13-didecanoate (4 alpha-PDD) fails to affect 125I-GM-CSF binding. PMA promotes phosphorylation on tyrosine residues of several proteins, as demonstrated by Western blotting analysis using antiphosphotyrosine antibodies. The molecular masses of those proteins are 41, 55, 66, 78, 85, 104, and 115 kDa. GM-CSF increases the levels of the tyrosine phosphorylation of several proteins, the majority of which have similar Mr to those found in PMA-stimulated neutrophils. This increase, on all but the 41-kDa protein, is partially prevented by treatment of the cells with PMA. The inhibition by PMA of GM-CSF binding to its receptors and its phosphorylated effects is partially prevented by the protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine and, to a greater extent, by staurosporine. It is suggested that PMA, through the activation of protein kinase C, interrupts the excitation-response sequence initiated by GM-CSF, which includes tyrosine phosphorylation, and that the earliest altered step is the binding of GM-CSF to its receptor.
...
PMID:Phorbol ester inhibits granulocyte-macrophage colony-stimulating factor binding and tyrosine phosphorylation. 153 18

Injection of mice with either natural bovine bone-derived or human recombinant transforming growth factor beta 1 (TGF-beta 1) resulted in a significant increase of the macrophage and macrophage-granulocyte-forming capacity of their macrophage colony-stimulating factor (M-CSF)- and granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent bone marrow precursor cells. The increased potential for generating granulocytes and/or macrophages from bone marrow cells of mice injected with TGF-beta 1 was associated with an increase of the number of M-CSF- and GM-CSF-dependent bone marrow colony-forming units (CFU). The effect was selective, in that in vivo applied TGF-beta 1 did not affect interleukin 3 (IL-3)-dependent CFU. The data suggest that TGF-beta may be useful in recovery of bone marrow granulocyte- and macrophage-forming potentials following depletion caused by chemo- or radiotherapy.
...
PMID:In vivo regulation of hemopoiesis by transforming growth factor beta 1: stimulation of GM-CSF- and M-CSF-dependent murine bone marrow precursors. 156 60

We studied the effect of transforming growth factor-beta 1 (TGF-beta 1) on colony formation of leukemic blast progenitors from ten acute myeloblastic leukemia (AML) patients stimulated with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), interleukin-6 (IL-6), or interleukin-1 beta (IL-1 beta). These CSFs and interleukins by themselves stimulated the proliferation of leukemic blast progenitors without adding TGF-beta 1. G-CSF, GM-CSF, and IL-3 stimulated blast colony formation in nine patients, IL-6 stimulated it in five, and IL-1 beta stimulated in four. TGF-beta 1 significantly reduced blast colony formation stimulated by G-CSF, GM-CSF, or IL-6 in all patients. In contrast, TGF-beta 1 enhanced the stimulatory effect of IL-3 on blast progenitors from three cases, while in the other seven patients TGF-beta 1 reduced blast colony formation in the presence of IL-3. To study the mechanism by which TGF-beta 1 enhanced the stimulatory effect of IL-3 on blast progenitors, we carried out the following experiments in the three patients in which it occurred. First, the media conditioned by leukemic cells in the presence of TGF-beta 1 stimulated the growth of leukemic blast progenitors, but such effect was completely abolished by anti-IL-1 beta antibody. Second, the addition of IL-1 beta in the culture significantly enhanced the growth of blast progenitors stimulated with IL-3. Third, leukemic cells of the two patients studied were revealed to secrete IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) constitutively; the production by leukemic cells of IL-1 beta and TNF-alpha was significantly promoted by TGF-beta 1. Furthermore, the growth enhancing effect of TGF-beta 1 in the presence of IL-3 was fully neutralized by anti-IL-1 beta antibody. These findings suggest that TGF-beta 1 stimulated the growth of blast progenitors through the production and secretion of IL-1 beta by leukemic cells.
...
PMID:Enhancement by transforming growth factor-beta 1 (TGF-beta 1) of the proliferation of leukemic blast progenitors stimulated with IL-3. 171 97

Granulocyte-macrophage CSF (GM-CSF) is a potent stimulator of macrophages and neutrophils and is produced by rheumatoid arthritis (RA) synovium. We now report studies that identify some of the synovial cells and cytokines responsible for local GM-CSF production and gene expression in RA. GM-CSF was assayed by ELISA in supernatants from cultured RA fibroblast-like synoviocytes stimulated with various cytokines (IL-1 beta, TNF-alpha, macrophage-CSF, IFN-gamma, IL-6, and TGF-beta). Immunoreactive GM-CSF was detected in IL-1 beta and TNF-alpha-stimulated cultures, but not in cells cultured in medium or stimulated with any of the other cytokines. IL-1 and TNF-alpha had a synergistic effect on GM-CSF production. GM-CSF gene expression by fibroblast-like synoviocytes was analyzed by ribonuclease protection assay, Northern blot analysis, and in situ hybridization. Both IL-1 beta and TNF-alpha induced GM-CSF mRNA accumulation, with a maximum effect after 4 h of stimulation. We then studied GM-CSF production by macrophage-like synoviocytes (MLS) isolated from fresh synovial specimens by flow microfluorimetry. Fresh MLS spontaneously secreted the cytokine and exogenous IL-1 beta or TNF-alpha had no effect. After 1 wk in culture, additional stimulation with IL-1 beta or TNF-alpha was required for GM-CSF production. Finally, in situ hybridization performed on freshly isolated subpopulations of synovial cells, identified GM-CSF RNA transcripts in MLS.
...
PMID:Cytokines in chronic inflammatory arthritis. VI. Analysis of the synovial cells involved in granulocyte-macrophage colony-stimulating factor production and gene expression in rheumatoid arthritis and its regulation by IL-1 and tumor necrosis factor-alpha. 202 69


1 2 3 4 5 Next >>