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)

To evaluate the efficacy of recombinant murine granulocyte-macrophage colony-stimulating factor (rGM-CSF) in attenuating the myelosuppression associated with chemotherapy, the effects of 100 and 300 ng rGM-CSF, administered twice daily by intraperitoneal injection for 6 consecutive days to mice 24 hours after a dose of 200 mg/kg cyclophosphamide, were measured. Six days after the initial injection of rGM-CSF, a significant increase occurred in the absolute myeloid count compared to that of vehicle-treated animals. The difference was most pronounced on day 7, attaining levels of 327% and 428% of the control; these increases slowly declined to that of the control level by day 19. No significant effect was produced by rGM-CSF on the packed red cell volume or on the platelet count. Furthermore, the administration of rGM-CSF did not alter bone marrow cellularity or increase the number of marrow-derived hematopoietic stem cells. In contrast, a significant splenomegaly occurred, starting on day 6 and continuing until day 17. This was characterized by a pronounced increase in splenic-derived granulocyte (CFU-G), granulocyte-macrophage (CFU-GM), macrophage (CFU-M), megakaryocyte (CFU-MK), and erythroid (BFU-E, CFU-E) stem cells. The increases occurred between days 6 and 9 following the initial administration of rGM-CSF. These findings indicated that the administration of rGM-CSF to cyclophosphamide-treated animals causes an absolute increase in circulating myeloid cells and that these increases are derived from the spleen. The use of recombinant hematopoietic growth factors may permit the administration of more intensive chemotherapy through amelioration of chemically induced leukopenia.
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PMID:Effects of recombinant murine granulocyte-macrophage colony-stimulating factor in cyclophosphamide-treated mice. 201 56

This study reports the detection of an activity that stimulates the development of a subclass of burst-forming unit-erythroid (BFU-E) progenitors giving rise to small bursts in semi-solid cultures established in the presence of saturating concentrations of erythropoietin. These progenitors are considered to be mature BFU-E. The activity is found in extracts from kidney cells and appears to be physiologically regulated as it was respectively enhanced and decreased in kidneys from anemic and polycythemic mice. The disappearance of activity in kidney-cell extracts during long-term polycythemia correlated with an accumulation of mature BFU-E in the spleen and bone marrow of polycythemic mice. Using specific neutralizing antibodies and in vitro tests, we also show that this activity is different from hemopoietins known to share burst promoting activity (Interleukin-3 [IL-3], granulocyte-macrophage colony-stimulating factor [GM-CSF], Interleukin-4 [IL-4], erythropoietin [EPO], human interleukin for DA cells [HILDA]) and that it can stimulate erythroid differentiation in long term bone marrow cell cultures.
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PMID:Kidney cell lysates contain an activity that stimulates mature erythroid burst-forming-unit (mBFU-E) proliferation. 212 18

An increasing amount of data provides strong evidence for the complex multifactorial control of primary hemopoietic functions. Here we present a new multicellular functional unit, the Hematon, isolated from the light-density floating fraction of normal human bone marrow (BM) aspirates. The Hematon is organized in a compact, three-dimensional spheroid complex from central adipocytes, fibroblastoid cells, and resident macrophages that compartmentalize myeloid, erythroid, and megakaryocyte progenitor cells and their progenies. The Hematon fraction is more than twofold more abundant in progenitor cells when compared to the mononuclear cell (MNC) fraction as gauged by cytological techniques and by analysis of granulocyte-macrophage colony-forming unit (GM-CFU) populations. Individual Hematons may produce, within 2-3 weeks, up to 50,000 hemopoietic cells of different cell lineages in organotypic microcultures. Recombinant human hematopoietic growth factors interleukin 3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and macrophage colony-stimulating factor (M-CSF) significantly stimulated the endogenous cell production of some but not all of the individually treated Hematons, indicating the heterogeneity of factor-responsive cells within the Hematon population. Comparative observations of 184 BM aspirates support the hypothesis that the presence of Hematons in a BM aspirate correlates positively with homeostatic blood cell production, because the Hematon was present in normal BM (31/40) and it was rare among patients with myelodysplastic syndromes (15/53), acute myeloblastic leukemia (7/39), and chronic myelocytic leukemia (5/52). We suggest that the Hematon represents a unifying model around which the variability of fundamental BM functions and dysfunctions can be explored.
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PMID:Hematon, a multicellular functional unit in normal human bone marrow: structural organization, hemopoietic activity, and its relationship to myelodysplasia and myeloid leukemias. 218 30

The colony-stimulating factors (CSFs) are a group of acidic glycoproteins which are required for the proliferation of hematopoietic progenitor cells and for their differentiation into mature blood cells. Receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF) are present on a wide spectrum of cells including erythroid, mixed erythroid-non-erythroid, mixed myeloid and megakaryocytic progenitors, and on mature neutrophils, eosinophils and monocytes. A number of studies are now available which provide insights into the structure-function relationships of human GM-CSF. In an attempt to further understand the interaction between GM-CSF and its cell surface receptor, we have constructed models of the tertiary structure of human GM-CSF using the known disulfide bonding pattern, predictions of the secondary structure of the growth factor and a model based on conformational homologies among cytokines (Parry et al., J Mol Recognition 1988;1:107-110). When compared to a number of functional mapping studies, structural features of the model are consistent with the experimental data, and the model, in turn, leads to the generation of a number of testable hypotheses. The implications of these features in terms of receptor-ligand interaction are discussed.
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PMID:Molecular modeling of human granulocyte-macrophage colony-stimulating factor. 218 38

Granulocyte-macrophage colony-stimulating factor (GM-CSF) was given for three days (8 micrograms/kg/day) to 14 subjects who had solid tumors and normal hemopoiesis. The treatment induced a rapid 3- to 5-fold increase in the number of circulating neutrophils, eosinophils and monocytes. Lymphocytes, platelets and reticulocytes were unmodified during treatment. Activation of circulating neutrophils during GM-CSF treatment was demonstrated by a significant, increased release of neutrophil-derived platelet-activating factor after stimulation with N-formyl-methionyl-leucyl-phenylalanine, tumor necrosis factor-alpha or phagocytosis. The granulomonocytosis was dependent on increased bone marrow production of mature cells. Using the thymidine suicide technique, we observed that GM-CSF more than doubled the percentage of granulocyte-macrophage and megakaryocyte colony-forming units (CFU-gm and CFU-meg) and erythroid burst-forming units (BFU-e) in the S phase of the cell cycle. However, at the level of morphologically recognizable cells with autoradiography, we observed that GM-CSF increased the labeling index of the granulo-monopoietic cells, whereas that of the erythroblasts was unchanged. These data suggest that in accordance with in vitro observations, GM-CSF exerts its activity through all granulo-monopoietic lineages, whereas other cytokines (erythropoietin, thrombopoiesis-stimulating factors) may be needed to fully exploit the proliferative stimulus of GM-CSF on BFU-e and CFU-meg. After treatment discontinuation, the proliferative activity drops to values lower than before treatment, suggesting a period of relative refractoriness of marrow progenitors to the cytocidal effect of cell cycle-specific antineoplastic agents. This hypothesis is under evaluation in a controlled clinical trial where GM-CSF is given prior to chemotherapy.
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PMID:Human GM-CSF in vivo: identification of the target cells and of their kinetics of response. 218 41

Since enrichment of human bone-marrow hematopoietic progenitors is becoming more feasible and since purified growth factors are now available, we sought to study the action of growth factors on CD34-positive enriched cultures of human bone-marrow cells. We tested the effect of recombinant human (rh) granulocyte-macrophage colony-stimulating factor (GM-CSF), rh interleukin-3 (IL-3), or a unique biologic response modifier, bryostatin 1, on the growth of purified CD34 cells obtained by limiting dilution in single-cell cultures. We have shown previously that bryostatin 1 stimulates both myeloid and erythroid progenitors of human origin in vitro. In this study both IL-3 and GM-CSF supported colony formation from 500, 100, or single-cell cultures at equivalent plating efficiences, suggesting a direct action of these factors on hematopoietic cell growth. Conversely, bryostatin 1 did not support the growth of CD34 cells in single-cell cultures, and the cloning efficiency increased with increasing the number of cells in the culture. To test whether the indirect action of bryostatin 1 might be mediated through the production of growth factors by accessory cells, studies were performed using antibodies directed against human IL-3 and GM-CSF in culture with bryostatin 1 and normal human bone-marrow cells. Results are consistent with the hypothesis that bryostatin 1 could have a stimulatory effect on the accessory cell populations to produce either IL-3 or GM-CSF. Further support for this notion was obtained by demonstrating that T cells, which are cells known to be able to produce IL-3 and GM-CSF, are stimulated by bryostatin 1 to express messenger RNA (mRNA) for specific growth factors, including GM-CSF. These results provide further support that bryostatin 1 may be a useful clinical agent to stimulate hematopoiesis in vivo.
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PMID:The action of bryostatin on normal human hematopoietic progenitors is mediated by accessory cell release of growth factors. 220 May 37

Patients may be intolerant of zidovudine for several reasons, the most prominent being hematologic toxicity. In vitro studies demonstrate that zidovudine is toxic to the myeloid and erythroid precursors in the bone marrow; at concentrations of zidovudine near those associated with the optimal antiviral effect in vitro, the proliferative capability of these progenitor cells is reduced 50%-70%. The clinical manifestations of anemia and leukopenia generally are time- and dose-dependent. Strategies for alleviating the hematologic toxicity of zidovudine include the use of hematopoietic growth factors, such as erythropoietin, granulocyte colony-stimulating factor, or granulocyte-macrophage colony-stimulating factor. Myopathy, a recently recognized toxic effect of zidovudine, also appears to be time-dependent. Patients often complain of muscle weakness and discomfort and exhibit an associated elevation in creatine phosphokinase level; dose reduction or discontinuation of therapy generally is required. Some patients have experienced high fever, nausea, and vomiting; however, these effects are unusual and of unclear etiology. The substantial proportion of patients with AIDS or AIDS-related complex receiving zidovudine who experience hematologic or muscular toxicity may benefit from treatment with new antiviral agents, such as dideoxyinosine, with toxicity profiles different from that of zidovudine.
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PMID:Zidovudine intolerance. 220 Oct 71

We have modified a limiting dilution liquid culture assay, used to quantify hematopoietic progenitor frequency, to simultaneously assess cellular proliferation and differentiation. The frequency of colonies from cord blood obtained with recombinant human interleukin 3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in combination was comparable to cultures with IL-3 alone. However, IL-3 and GM-CSF in combination were synergistic for higher granulocyte proliferation than IL-3 alone, indicating that enhanced granulocyte production occurred via action of GM-CSF on progenitor cell populations already stimulated into proliferation by IL-3. Peak proliferation was evident at 4 weeks in culture, with metamyelocytes predominating; at 6 weeks, mostly neutrophils and eosinophils were present, and eosinophils were more numerous in cultures with IL-3. Increasing concentrations of erythropoietin (epo) in liquid culture with IL-3 or GM-CSF decreased absolute granulocyte yield while stimulating erythroid proliferation. The influence of epo on lineage morphology for cells plated in methylcellulose was markedly less evident by comparison, arguing against an inductive effect of epo to shift progenitor cell lineage. This liquid culture methodology may be a useful tool for preclinical screening of cytokines on human hematopoietic progenitor cells.
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PMID:Hematopoiesis in limiting dilution cultures: influence of cytokines on human hematopoietic progenitor cells. 220 54

In this report, the biological properties of human recombinant interleukin-3 (rhIL-3) were studied. We investigated the range of unfractionated, purified and single cell human progenitors responsive to IL-3; compared the colony types observed with those obtained in the presence of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) or granulocyte-CSF (G-CSF). The results show that IL-3 directly stimulates the formation of colonies derived from eosinophil and, to a lesser degree, granulocyte and macrophage progenitors. In combination with erythropoietin, it supports the development of erythroid and mixed-erythroid colonies. Furthermore, the data show that IL-3 is a more potent stimulus for both erythroid and eosinophil progenitors than GM-CSF. Interleukin-3 stimulates the formation of both compact and dispersed colonies derived from eosinophil progenitors, whereas GM-CSF stimulates the formation of only the compact type. We conclude that some of the proliferative effects of IL-3 observed on unfractionated and semipurified bone marrow populations are indirect and most likely involve accessory cell interactions.
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PMID:Proliferative properties of unfractionated, purified, and single cell human progenitor populations stimulated by recombinant human interleukin-3. 229 98

Platelet-derived growth factor (PDGF) is an important serum regulator of erythropoiesis in vitro. We have now obtained evidence suggesting that PDGF-like molecules may also modulate erythropoiesis in vivo. Western blot analysis of cytoplasmic extracts from Rauscher murine erythroleukemia cells and phenylhydrazine-treated mouse splenic erythroid cells revealed the presence of several PDGF-like proteins. The presence of PDGF-like proteins in the cytoplasm of these two erythroid cell types was confirmed by immunohistochemical staining. Using a serum-free biologic assay, PDGF-like biological activity was found in cell lysates and conditioned medium of both Rauscher cells and phenylhydrazine-treated mouse erythroid cells. Subcellular localization experiments revealed the biological activity to be concentrated in the cytosolic fraction. Using a series of antibodies to hematopoietic growth factors we demonstrated that PDGF-like biological activity was specifically immunoprecipitated by both monoclonal and polyclonal anti-human PDGF antibodies but not by antibodies to burst-promoting activity, granulocyte-macrophage colony-stimulating factor, IL-3, or erythropoietin. Taken together, the data are consistent with the hypothesis that PDGF-like molecules play a role in the regulation of mammalian erythropoiesis in vivo.
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PMID:Characterization of biologically active, platelet-derived growth factor-like molecules produced by murine erythroid cells in vitro and in vivo. 229 3


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