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)

We previously proposed the hypothesis that the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) plays a pivotal role in the pathogenesis of rheumatoid arthritis (RA) based on our observations that it is the dominant inducer of interleukin-1 (IL-1) and granulocyte-macrophage colony-stimulating factor (GM-CSF) production in RA synovial joint mononuclear (MNC) cells in culture. Since TNF-alpha acts via two membrane receptors, we have extended those studies to investigate the distribution of the p55 and p75 TNF receptors (TNF-R) in RA tissue. Surface receptor expression was quantitated by flow cytometry using monoclonal antibodies specific to the p55 (HTR-9) and the p75 (UTR-1) TNF-R. Both receptors were significantly increased on MNC isolated from the synovial membrane of RA patients compared to normal or RA peripheral blood MNC. Interestingly, the p75 TNF-R was increased both on large monocytic/macrophage-type cells and CD3+ lymphocytes. Furthermore, there was a significant increase in the proportion of CD3+ cells in RA synovial fluid expressing the p75 TNF-R, compared to matched peripheral blood MNC. In contrast to RA synovial MNC, p75 or p55 TNF-R expression was not significantly increased in osteoarthritis synovial MNC. In addition, Northern blot analysis indicated abundant expression of both p55 and p75 mRNA in RA synovial joint MNC. This was in contrast to normal peripheral blood MNC cells which contained little or no constitutive TNF-R mRNA; following stimulation with phytohemagglutinin and IL-2, a rapid and transient expression of both receptor mRNA was induced. These results, therefore, indicate that in RA synovial joint tissue there is up-regulation of both p55 and p75 TNF-R mRNA and surface protein expression, and with the presence of TNF-alpha in RA tissues, these results provide support to our hypothesis that TNF-alpha is of critical importance in the pathogenesis of RA.
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PMID:Enhanced expression of tumor necrosis factor receptor mRNA and protein in mononuclear cells isolated from rheumatoid arthritis synovial joints. 132 May 71

Synovial fibroblasts are likely to be a significant source of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte-CSF (G-CSF), which could be crucial to the pathogenesis of rheumatoid arthritis. Using specific enzyme-linked immunosorbent assays (ELISAs) and Northern analysis, GM-CSF and G-CSF expression were followed in human synovial fibroblast-like cells in response to a number of agents, either alone or in the presence of an optimal stimulatory concentration of interleukin-1 (IL-1). For both CSFs, interferon-gamma (100 U/mL) did not increase their levels but dramatically suppressed the stimulatory action of IL-1, while basic fibroblast growth factor (10(-8) mol/L), although nonstimulatory by itself, potentiated IL-1 action. The glucocorticoid, dexamethasone (10(-7) mol/L), inhibited IL-1-stimulated CSF production. However, evidence was obtained for noncoordinated CSF regulation. Cyclooxygenase inhibitors potentiated the action of IL-1 on GM-CSF synthesis but suppressed G-CSF synthesis, suggesting that endogenous cyclooxygenase products can have opposite effects in modulating the levels of each CSF. Also, the lymphokine, IL-4 (250 pmol/L), slightly inhibited GM-CSF formation in the presence of IL-1 but elevated the G-CSF levels in these cultures without having an effect by itself. Transforming growth factor beta (less than or equal to 20 ng/mL) did not modulate levels of either CSF. Mesenchymal cell production of both GM-CSF and G-CSF is generally viewed as being under coordinate control; our findings suggest that their synthesis in IL-1-stimulated human synoviocytes can be modulated by a number of agents, in some cases with divergent actions depending on which CSF is examined.
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PMID:Cytokine regulation of colony-stimulating factor (CSF) production in cultured human synovial fibroblasts. II. Similarities and differences in the control of interleukin-1 induction of granulocyte-macrophage CSF and granulocyte-CSF production. 137 87

Neutrophils, an abundant cell type at sites of inflammation, have the ability to produce a number of cytokines, including interleukin 1 (IL-1), IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-alpha). In this study, we have examined the ability of human neutrophils to produce the IL-1 receptor antagonist (IL-1Ra), a 17-23-kD protein recently isolated and cloned from macrophages. Since IL-1Ra has been shown to inhibit both the in vitro and in vivo effects of IL-1, its production by large numbers of tissue-invading neutrophils might provide a mechanism by which the effects of IL-1 are regulated in inflammation. Using antibodies that are specific for IL-1Ra and a cDNA probe encoding for this protein, we were able to show that neutrophils constitutively produce IL-1Ra. However, after activation by GM-CSF and TNF-alpha, IL-1Ra was secreted into the extracellular milieu where it constituted the major de novo synthesized product of activated neutrophils. None of a large array of other potent neutrophil agonists were found to affect the production of IL-1Ra by neutrophils. Quantitative measurements by enzyme-linked immunosorbent assay revealed that intracellular IL-1Ra is in eightfold excess of the amount secreted in supernatants when studying nonactivated neutrophils. However, in GM-CSF- and TNF-alpha-activated cells, this difference was reduced to values between four- and fivefold, as virtually all of the de novo synthesized IL-1Ra was secreted. In activated cells, the intracellular content of IL-1Ra was found to be in the 2-2.5-ng/ml range per 10(6) neutrophils, whereas levels reached the 0.5-ng/ml range in supernatants. This would imply that IL-1Ra is produced in excess of IL-1 by a factor of at least 100, an observation that is in agreement with the reported amounts of IL-1Ra needed to inhibit the proinflammatory effects of IL-1. Neutrophils isolated from an inflammatory milieu, the synovial fluid of patients with rheumatoid arthritis, were found to respond to GM-CSF and TNF-alpha in terms of IL-1Ra synthesis, indicating that the in vitro observations made in this study are likely to occur in an inflammatory setting in vivo.
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PMID:Human neutrophils produce high levels of the interleukin 1 receptor antagonist in response to granulocyte/macrophage colony-stimulating factor and tumor necrosis factor alpha. 138 77

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)
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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

It is now generally accepted that many cytokines are involved in the pathogenesis of autoimmune disease, either directly by causing tissue destruction or indirectly through the activation of autoreactive and inflammatory cells. Thus, cytokines, such as tumor necrosis factor-alpha, are implicated in the pathogenesis of rheumatoid arthritis based on in vitro studies on synovial tissue from patients with rheumatoid arthritis, which suggest that the effects of tumor necrosis factor-alpha are amplified by its potential to induce other pro-inflammatory cytokines, such as interleukin-1 and granulocyte-macrophage colony-stimulating factor. Transgenic mouse technology has shown that mice expressing the human tumor necrosis factor-alpha gene develop a polyarthritis. Interleukin-2 has also been identified by transgenic technology as a cytokine involved in the pathogenesis of insulin-dependent diabetes mellitus through the activation and stimulation of growth of autoreactive T cells.
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PMID:Cytokines in autoimmunity. 146 99

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multipotent hematopoietic growth factor, which is mainly produced by T-cells and stromal cells. Beside the stimulating effects on mature granulocytes, it induces the expression of HLA class II-antigen on synovial tissue-cells in patients with rheumatoid arthritis. The concentrations of GM-CSF in the plasma of 87 patients with rheumatoid arthritis, 48 patients with spondyloarthropathy, 17 patients with systemic lupus erythematosus (SLE), and 43 healthy control persons were investigated. We used an immunoradiometric assay (IR-MA) with a detection limit of 30 pg/ml to measure the GM-CSF concentrations in plasma. The GM-CSF levels of 29 patients with severe rheumatoid arthritis (366 +/- 61 pg/ml, p less than 0.05), 58 patients with moderate rheumatoid arthritis (376 +/- 44 pg/ml, p less than 0.0001), and of 17 patients with SLE (256 +/- 41 pg/ml, p less than 0.05) were elevated compared to the control group (174 +/- 18 pg/ml). No significant differences in the mean GM-CSF plasma levels between the patients with spondyloarthropathy (190 +/- 32 pg/ml) and the control group were found. GM-CSF concentrations as high as 1300 pg/ml were detected in the synovial fluids of patients with rheumatoid arthritis. GM-CSF concentrations in the plasma of patients with severe rheumatoid arthritis were correlated with the plasma concentrations of the soluble interleukin-2-receptor (sCD25) (R = +0.53).
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PMID:[Plasma GM-CSF concentrations in rheumatoid arthritis, systemic lupus erythematosus and spondyloarthropathy]. 150 58

Cell-free synovial fluid from patients with rheumatoid arthritis stimulated the NADPH oxidase activity in human neutrophils, which reached a peak 15-20 min after addition. Insoluble immunoglobulin aggregates isolated from these fluids activated a similar pattern of oxidase activity. However, when synovial fluid was added to neutrophil suspensions which had been previously exposed to granulocyte-macrophage colony-stimulating factor, the stimulated oxidase activity was biphasic, in that an additional transient activity was observed which reached a peak within 5 min of addition. The additional neutrophil-stimulating activity could not be sedimented by centrifugation at 330,000 g-min, and only activated oxidase activity in neutrophils which had previously been primed. The neutrophil-stimulating activity in this soluble fraction was removed by Protein A affinity chromatography, and activity was recovered in eluates from this column. Thus activity in this soluble fraction from synovial fluid is attributed to the presence of soluble immunoglobulin aggregates. Whereas oxidase activity stimulated by the isoluble immunoglobulin aggregates was inhibited by staurosporine (and hence largely dependent on the activity of protein kinase C), the activity stimulated by the soluble immunoglobulin aggregates was staurosporine-insensitive. The soluble immunoglobulin aggregates were present at significantly higher levels in synovial fluids from patients with rheumatoid arthritis compared with those from other joint arthropathies. Thus rheumatoid synovial fluids possess heterogeneous immunoglobulin aggregates which activate neutrophils via distinct molecular pathways. As neutrophils within rheumatoid joints are primed, the soluble immunoglobulin aggregates are likely to be of importance in disease pathology.
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PMID:Activation of neutrophil reactive-oxidant production by synovial fluid from patients with inflammatory joint disease. Soluble and insoluble immunoglobulin aggregates activate different pathways in primed and unprimed cells. 153 May 67

This study was undertaken in an effort to understand the role of cytokines in T lymphocyte trafficking into inflamed synovium and in the potential enhancement of antigen presentation by human synovial fibroblasts. We found that interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF alpha), and interferon-gamma (IFN gamma) each increased the cell surface expression of intercellular adhesion molecule 1 (ICAM-1) on human synovial fibroblasts in a dose- and time-dependent manner. Maximal ICAM-1 expression occurred within 8 hours of induction, with the following order of efficacy: IFN gamma greater than TNF alpha greater than IL-1 beta. The number of cells bearing the ICAM-1 antigen also increased, from a basal level of approximately 30% to more than 83% after cytokine induction (for all 3 cytokines). ICAM-1 expression rapidly decreased following cytokine removal. The expression of lymphocyte function-associated antigen 3 was also examined, but it was not changed by any of the 3 cytokines. Class I major histocompatibility complex antigen expression was increased modestly by all 3 cytokines, and expression was maximal by 24 hours after treatment. Only IFN gamma induced HLA class II antigen expression, and this expression persisted for up to 6 days following removal of the lymphokine. IL-6 and granulocyte-macrophage colony-stimulating factor had no effect on any of the parameters examined. Our data support an interactive role for inflammatory cytokines and the expression of adhesion ligands and HLA antigens by human synovial fibroblasts in the pathogenesis of synovial inflammation in rheumatoid arthritis.
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PMID:Role of cytokines in inflammatory synovitis. The coordinate regulation of intercellular adhesion molecule 1 and HLA class I and class II antigens in rheumatoid synovial fibroblasts. 170 92

Granulocyte-macrophage colony-stimulating factor (GM-CSF), in addition to being a growth factor for granulocytes and macrophages, is an activator of cells of the monocyte/macrophage lineage and induces HLA class II expression and cytokine synthesis in these target cells. Macrophage activation and class II expression are prominent features in rheumatoid arthritis (RA) joints, but the mechanism of their stimulation is not understood, since interferon-gamma, the major stimulus of class II expression, is not usually detectable at the protein level in synovial cell culture supernatants. We have, therefore, studied GM-CSF expression in cultures of cells derived from joints affected by RA and osteoarthritis (OA), and show that GM-CSF is produced spontaneously both by RA synovial cells and to a lesser extent by OA synovial cells in the absence of extrinsic stimuli. GM-CSF production continues for the 5-day duration of the culture period. Using neutralizing antibodies to tumor necrosis factor (TNF)-alpha we demonstrated that GM-CSF production in RA synovial cell cultures is dependent on the continued presence of active TNF-alpha. This result supports our concept that continued activation of the cytokine network is a marked feature of RA, and that TNF-alpha plays a pivotal role in this network, by regulating the production of other pro-inflammatory cytokines, such as interleukin 1, as demonstrated previously, and GM-CSF.
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PMID:Expression of granulocyte-macrophage colony-stimulating factor in rheumatoid arthritis: regulation by tumor necrosis factor-alpha. 191 59

A useful approach to establishing the biologic actions, in vivo, of granulocyte-macrophage colony-stimulating factor (GM-CSF) is to assess the consequences of long-term elevation of the factor in transgenic mice. Two lines of transgenic GM-CSF mice were analyzed. The major abnormality exhibited was an elevation in the number of macrophages, eosinophils, and polymorphs in the peritoneal and pleural cavities. Disease states exhibited by the lines were dependent on the insertion site of the GM-CSF gene. These disease states seem best explained on the basis of CSF-mediated macrophage activation and may provide valuable clues as to the cause of comparable human diseases such as malignant histiocytosis, polymyositis, or rheumatoid arthritis.
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PMID:Transgenic mice as models of hemopoiesis. 201 70


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