UNIPROT:P04141 - FACTA Search

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)

CD34+ precursors in normal human bone marrow (BM) generate large numbers of dendritic cells alongside macrophages and granulocytic precursors when cultured for 12 to 14 days in c-kit ligand, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha). This study reports an intermediate cell type that develops by day 6, and has the potential to differentiate into either macrophages or dendritic cells. When the d6 progeny are depleted of mature macrophages and residual CD34+ precursors, a discrete CD14+ HLA-DR+ population persists in addition to immunostimulatory CD14- HLA-DR() dendritic cells. Half of the CD14+ HLA-DR+ population is in cell cycle (Ki-67+), but colony-forming units (CFUs) are no longer detectable. The calls are c-fms+, but lack myeloperoxidase and nonspecific esterase. They also possess substantial phagocytic and allostimulatory activity. These post-CFU, CD14+ HLA-DR+ intermediates develop into typical macrophages when recultured in the absence of exogenous cytokines. M-CSF supports up to approximately 2.5-fold expansion of macrophage progeny. In contrast, the combination of GM-CSF and TNF-alpha supports quantitative differentiation into dendritic cells, lacking c-fms, CD14, and other macrophage properties, and expressing HLA-DR, CD1a, CD83, CD80, CD86, and potent allostimulatory activity. Therefore, normal CD34+ BM precursors can generate a post-CFU bipotential intermediate in the presence of c-kit ligand, GM-CSF, and TNF-alpha. This intermediate cell type will develop along the dendritic cell pathway when macrophages are removed and GM-CSF and TNF-alpha are provided. Alternatively, it can differentiate along a macrophage pathway when recultured with or without M-CSF.
...
PMID:Dendritic cells and macrophages can mature independently from a human bone marrow-derived, post-colony-forming unit intermediate. 863 19

We investigated the properties of granulocyte-macrophage (GM) progenitors obtained from patients with juvenile chronic myelogenous leukemia (JCML). CD34+ bone marrow cells from a patient with JCML, unlike normal bone marrow cells, generated a large number of cells in serum-containing liquid culture without additional hematopoietic factors. In serum-deprived culture, only granulocyte colony-stimulating factor (G-CSF) had a modest stimulatory effect on GM colony growth in normal controls. In contrast, stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-3 (IL-3), as well as G-CSF, when tested individually, generated significant numbers of GM colonies in some JCML patients. All two-factor combinations generated significantly more GM colonies in JCML compared with normal controls. In particular, GM-CSF plus SCF exerted an interaction equivalent to the all-factor combination in most patients. Significant differences in the size and constituent cells of GM colonies stimulated by GM-CSF plus SCF were also observed. These results suggest that one possible mechanism for the excessive cell production in JCML is the strong proliferation of GM progenitors induced by hematopoietic factors, especially SCF. According to immunofluorescent analysis, however, it is unlikely that this multiplication is due to an increase in the cell surface expression of c-kit receptors on JCML progenitors.
...
PMID:Aberrant growth of granulocyte-macrophage progenitors in juvenile chronic myelogenous leukemia in serum-free culture. 864 32

The human homolog of the murine flt3/flk2 gene product is a tyrosine kinase receptor that plays a role in regulating the proliferation and differentiation of cells in the hematopoietic system. Using a plasma-clot clonal assay and a long-term bone marrow culture (LTBMC) system, we studied the effects of the recently cloned human flt3 ligand (FL) alone and in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), or stem cell factor (c-kit ligand [KL]) on human megakaryocytopoiesis. The effects of FL on the primitive megakaryocyte (MK) progenitor cell, the burst-forming unit-megakaryocyte (BFU-MK), and the more differentiated colony-forming unit-megakaryocyte (CFU-MK) were determined. FL alone had no megakaryocytic colony-stimulating activity (MK-CSA), but was capable of augmenting the MK-CSA of both GM-CSF and IL-3. FL synergized with IL-3 at the level of both CFU-MK and BFU-MK and with GM-CSF and KL at the level of CFU-MK. Although FL alone exhibited a limited potential in sustaining long-term megakaryocytopoiesis in vitro, it synergistically augmented the ability of IL-3 and KL, alone or in association, to promote long-term megakaryocytopoiesis. These data indicate that multiple cytokines are necessary to optimally stimulate the proliferation of both classes of MK progenitor cells and that FL plays a significant role in this process by amplifying the MK-CSA of GM-CSF, IL-3, and KL.
...
PMID:The effects of human FLT3 ligand on in vitro human megakaryocytopoiesis. 864 63

Recombinant human interferon-inducible protein-10 (rIP-10) has been recently identified, purified and shown to suppress the multiplication of normal marrow early hemopoietic progenitors. In the present study we investigated the effect of rIP-10 on different normal and acute myelogenous leukemia (AML) progenitor populations. We first studied hematologically normal bone marrow using the delta culture assay, in which marrow low-density cells were incubated in liquid culture with recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) for 1 week, to allow the differentiation of mature progenitors, and thereafter cultured in methylcellulose in the presence of rGM-CSF and recombinant erythropoietin (rEPO). In this assay rIP-10 significantly inhibited the proliferation of normal marrow hemopoietic progenitors in a dose-dependent fashion. However, when fresh normal marrow cells were cultured in methylcellulose without preincubation in liquid culture, rIP-10 did not affect the growth of colony-forming cells. In contrast, when recombinant c-kit ligand (rKL) was added to rGM-CSF and rEPO, an increment in colony numbers was observed that was eliminated by rIP-10. Similar experiments performed with low-density, non-adherent, T cell-depleted AML marrow cells, obtained from 12 untreated adult AML patients, revealed qualitatively similar results: rIP-10 inhibited the proliferation of AML progenitors in the AML delta assay but did not affect the growth of rGM-CSF-responsive AML colony-forming cells when plated in semisolid media in the presence of rGM-CSF. When rKL was added to rGM-CSF during plating in an effort to recruit additional AML progenitor populations, there was an increment in leukemic blast colony numbers that was eliminated by rIP-10. As observed with normal progenitors, the effect of rIP-10 on these AML progenitors was concentration-dependent, statistically significant and reversible with a rIP-10-neutralizing antiserum. To delineate the mechanism of action of rIP-10 we used the thymidine suicide assay and found that rIP-10 significantly reduced the fraction of leukemic progenitors synthesizing DNA. Our data suggest the rIP-10 inhibits the proliferation of (probably immature) AML progenitor populations by reducing the fraction of cells undergoing DNA synthesis. Additional studies are needed to further elucidate the mechanism of this inhibition and to determine the potential clinical benefits of rIP-10 in future therapies for AML.
...
PMID:Human recombinant interferon-inducible protein-10 inhibits the proliferation of normal and acute myelogenous leukemia progenitors. 865 68

Although much is now known about the biological properties of the c-kit receptor and its ligand, stem cell factor (SCF), little is known of the structural basis for the binding and function of this hematopoietic cytokine. By analyzing the activities of chimeric interspecies and homologue muteins and epitope mapping of a monoclonal antibody (MoAb) to the human protein, we have found that three distinct regions of SCF are essential for full biological function. Homologue and interspecies swapping of polypeptide sequences between the amino terminus and G35, between L79 and N97, and between R121 and D128 reduced or eliminated the ability of the chimera to act in synergy with murine granulocyte-macrophage colony-stimulating factor (GM-CSF) to promote hematopoietic colony formation. Moreover, a nonconformation-dependent MoAb that neutralizes human, but not murine SCF, was found to bind to residues within the L79-N97 segment of the human homologue. As these three regions localize to the putative first, third, and fourth helices of the protein, findings remarkably similar to previous studies of cytokines as diverse as growth hormone, GM-CSF, and interleukin (IL)-4, our results suggest that cytokines of multiple classes share a common functional organization.
...
PMID:Structure-function relationships of stem cell factor: an analysis based on a series of human-murine stem cell factor chimera and the mapping of a neutralizing monoclonal antibody. 869 90

Platelets and megakaryocytes express Fc receptors for IgG which are encoded by the Fc gamma RIIA gene. In an effort to establish a cellular model for induction of Fc gamma RIIA expression during megakaryocyte development by hematopoietic growth factors, steady-state Fc gamma RIIA mRNA levels were monitored in c-kit receptor-positive megakaryocytic cells (M07e, HEL, and Dami) in response to c-kit ligand (KL; also known as stem cell factor, mast cell growth factor, or Steel factor). Northern blot analysis showed that exposure of cells to KL led to significant increases in Fc gamma RIIA levels in M07e (15 x at 24 hours), with smaller increases in HEL (1.9 x at 2 hours) and Dami (1.6 x at 24 hours) cells. K562 cells, which lack c-kit receptor, showed no effect of KL on modulating Fc gamma RIIA mRNA levels. The effects of KL were specific for Fc gamma RIIA, as there were no effects on platelet factor 4 (PF4), gamma-globin, or GATA-1 mRNA levels. Effects of KL, alone and in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF) and gamma-interferon (IFN-gamma), on surface Fc gamma RIIA expression were assessed by flow cytometry using anti-Fc gamma RII monoclonal antibody IV.3. In M07e cells, KL alone and in combination led to significant increases in the percentage of cells positive for surface Fc gamma RIIA and the mean cell fluorescence intensity. Transient transfection studies of an Fc gamma RIIA promoter-luciferase reporter gene in the presence or absence of KL showed increased reporter gene expression in KL-treated cells, with the largest increase (3.7-fold) in the M07e cells. In HEL and Dami cells, other cytokines active in megakaryocytopoiesis when used alone (interleukin-3 [IL-3], IL-6, IL-11, GM-CSF) had negligible activity in increasing reporter gene activity. These results suggest that increased levels of Fc gamma RIIA mRNA after KL treatment of M07e cells are a result, in part, of increased Fc gamma RIIA gene transcription. Our results indicate that M07e cells represent a cellular model for KL-induced Fc gamma RIIA expression in early megakaryocyte development.
...
PMID:Human c-kit ligand (stem cell factor) induces platelet Fc receptor expression in megakaryoblastic cells. 876 99

The effect of the mast cell growth factor (MGF), also known as stem cell factor, steel factor, and kit ligand, alone or in combination with other GFs on clonogenic blast cell growth in 23 patients with acute myeloblastic leukemia (AML) was investigated. MGF alone enhanced colony formation by about 35%, being clearly stimulatory (> 20% increase in colony numbers) in nine patients. The additive effect of MGF on colony growth was observed in combination with interleukin-3 (IL-3). Preincubation of the cells with MGF in suspension did not sensitize them to the effect of IL-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), G-CSF, or IL-4 in a clonogenic cell culture assay. Although almost all the blast cell samples expressed the c-kit the receptor for MGF, at the mRNA and/or the protein level, the cells did not necessarily respond to exogenous MGF. On the other hand, blast cells were able to respond to exogenous MGF even when the cells themselves expressed MGF. Neither the expression of MGF nor the response of blast cells to exogenous MGF was related to the capability of the cells to form colonies spontaneously. In conclusion, MGF alone, but especially combined with IL-3, was a potent growth factor for clonogenic blast cells in AML. Autocrine production of MGF by AML blast cells analyzed at the mRNA level was not related to autonomous growth of the cells.
...
PMID:Effect of mast cell growth factor on clonogenic blast cell growth in acute myelogenous leukemia. 877 15

We previously demonstrated that murine MS-5 and SI/SI4 cell lines induce the proliferation of human factor-dependent UT-7 cells in the absence of normally required human cytokines and also stimulate the differentiation of CD34+/CD38-LTC-ICs. We report in this study that the effect of MS-5 cells on UT-7 cells can be completely explained by the synergistic action of nerve growth factor (NGF) and stem cell factor (SCF) produced by these murine stromal cells. Purified murine NGF was able to support short-term clone formation and long-term growth of UT-7 cells in suspension cultures as efficiently as rhu-granulocyte-macrophage colony-stimulating factor. NGF action was mediated through the TrkA receptor, in which messenger RNA (mRNA) was easily detected in UT-7 cells by Northern blot. MS-5 cells strongly expressed NGF mRNA in Northern blot, and direct implication of MS-5-derived NGF in the induction of UT-7 cells proliferation was demonstrated in inhibition assays with an anti-NGF monoclonal antibody (MoAb) that neutralized by 84% +/- 4.1% (n = 5) UT-7 clone formation. However, NGF did not act alone, and several arguments demonstrated the synergistic action of MS-5-derived SCF: (1) an anti-c-kit partially inhibited UT-7 cells clone formation in coculture assays, (2) SCF and NGF synergized in an H3-TdR incorporation assay, and (3) the stimulatory effect of 10x-concentrated MS-5 supernatant was completely inhibited by an anti-c-kit but not by an anti-NGF, and levels of soluble NGF (1.2 ng/mL) detected by enzyme-linked immunosorbent assay in 10x supernatant of MS-5 cells cultures were below the biologically active concentrations. In contrast, although MS-5 cells also promoted the differentiation of very primitive CD34+/CD38- human stem cells both in colony assays and long-term cultures, we could not incriminate MS-5-derived NGF in the observed effect: an anti-NGF MoAb did not inhibit the synergistic effect of MS-5 cells in colony assays or long-term cultures nor did soluble muNGF duplicate MS-5 effect and survival of CD34+/CD38- clonogenic progenitor cells promoted by MS-5 was unaffected by an anti-NGF and was not induced by soluble NGF alone or combined with SCF. In contrast, NGF in synergy with SCF supported the short-term maintenance of high numbers of CD34+/CD38+ mature erythroid progenitors probably through an indirect mechanism implying macrophages. These results suggest that NGF, in which the primary target cells are outside the hematopoietic system, is present in the marrow environment and might act at some steps of hematopoietic stem cell development. These results also underline that the response of cell lines and normal stem cells to stromal cells is mediated by different pathways.
...
PMID:Nerve growth factor is involved in the supportive effect by bone marrow--derived stromal cells of the factor-dependent human cell line UT-7. 878 16

Peripheral blood progenitor cells (PBPCs) obtained from cytapheresis products (CPs) of tumor patients undergoing mobilizing chemotherapy for PBPC support and dose-intensified anticancer chemotherapy initiate multilineage human hematopoiesis after intraperitoneal (i.p.) transplantation into young severe combined immunodeficient (SCID) mice. The engraftment process was significantly accelerated by subcutaneous cotransplants of a rat fibroblast cell line stably transfected with a retroviral vector carrying the human interleukin-3 (hIL-3) gene and producing sustained in vivo levels of circulating human IL-3 over a prolonged period of time. These cotransplants were found to provide a suitable microenvironment for i.p. transplanted CD34-positive cells separated from PBPC preparations using immunomagnetic beads. Flow cytometry analysis and immunocytology revealed that selected PB CD34- cells, more than 90% pure, were capable of initiating and sustaining a productive multilineage hematopoiesis preferentially within the hIL-3-secreting cotransplants followed by release of mature human cells into the circulation, spleen and thymus. The percentages of human cells found in hIL-3 cotransplants 8 weeks post-transplantation (p.t.) were generally higher than those measured after transplantation of complete CP mononuclear cells containing comparable doses of CD34-positive cells. When selected PB CD34+ cells that were expanded ex vivo with combinations of human hematopoietic growth factors including the c-kit ligand (KL), interleukin (IL)-1 beta, IL-3, IL-6, erythropoietin (EPO) and granulocyte-macrophage colony-stimulating factor (GM-CSF) for 14 days were grafted to cotransplant-carrying SCID mice, a considerable loss of their proliferative potential was observed regardless of the HGF combination used. When experiments with grafts of selected PBPC were compared to those performed with selected/expanded PBPC on a per CD34+ cell basis the results revealed that over a dose range of 0.3 to 1.0 x 10(6) cells/graft the in vivo proliferative capacity of expanded cells was reduced by a factor of 2 to 3.
...
PMID:Fibroblasts retrovirally transfected with the human IL-3 gene initiate and sustain multilineage human hematopoiesis in SCID mice: comparison of CD34-enriched vs CD34-enriched and in vitro expanded grafts. 887 11

Bone marrow microvascular endothelial cells (BMEC) are a functional component of the bone marrow stroma and have been shown to release hematopoietic regulatory factors as well as to selectively adhere and support the proliferation and differentiation of CD34+ hematopoietic progenitors. An early passage of these cells was immortalized by transfection with a vector (pSVT) encoding the large T antigen of SV40. The transformed cell line (CDC/CU.BMEC-1) expresses the SV40 transcript, retains the primary cell expression of Ulex europeaus and vWF/ FVIII, and incorporates acetylated low-density lipoprotein. In addition, BMEC-1 mirrors the phenotype of the primary cells with only a few exceptions. Both cell populations express the cellular adhesion molecules ICAM-1 and PECAM and also VCAM-1 and ELAM-1 after upregulation by tumor necrosis factor-alpha. The fibronectin receptor, hyaluronate receptor, collagen receptor, integrins VLA-alpha 3, VLA-alpha 4, and beta 4, endoglin, collagen IV, CD58, and CD61 are also expressed. The only differences are that BMEC-1 expresses higher levels of ICAM-1, CD58, CD34, CD36, and c-kit than the primary cells. The supernatants of primary cell and BMEC-1 contain stem cell factor, interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-1 alpha, IL-11, and G-CSF. The functional significance of these hematopoietic cytokines was demonstrated in transwell cultures. Both cell populations supported the expansion of progeny from CD34+ cell-enriched cord blood mononuclear cells suspended in the upper chamber. These characteristics, plus the fact that BMEC-1 can be maintained independently of exogenous growth factors and exhibit contact inhibition, indicate that this cell line can be used to further define the role of BMEC in hematopoiesis.
...
PMID:BMEC-1: a human bone marrow microvascular endothelial cell line with primary cell characteristics. 895 64

<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>