Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The tyrosine kinase domains of the platelet-derived growth factor (PDGF) and colony-stimulating factor-1 (CSF-1)/c-fms receptors are interrupted by kinase inserts (ki) which vary in length and amino acid sequence. To define the role of the ki in the human alpha PDGF receptor (alpha PDGFR), we generated deletion mutants, designated alpha R delta ki-1 and alpha R delta ki-2, which lacked 80 (710 to 789) and 95 (695 to 789) amino acids of the 104-amino-acid ki region, respectively. Their functional characteristics were compared with those of the wild-type alpha PDGFR following introduction into a naive hematopoietic cell line, 32D. Biochemical responses, including PDGF-stimulated PDGFR tyrosine phosphorylation, phosphatidylinositol (PI) turnover, and receptor-associated PI-3 kinase activity, were differentially impaired by the deletions. Despite a lack of any detectable receptor-associated PI-3 kinase activity, 32D cells expressing alpha R delta ki-1 showed only partially impaired chemotactic and mitogenic responses and were capable of sustained proliferation in vitro and in vivo under conditions of autocrine stimulation by the c-sis product. 32D transfectants expressing the larger ki deletion (alpha R delta ki-2) showed markedly decreased or abolished biochemical and biological responses. However, insertion of the highly unrelated smaller c-fms (685 to 750) ki domain into alpha R delta ki-2 restored each of these activities to wild-type alpha PDGFR levels. Since the CSF-1R does not normally induce PI turnover, the ability of the c-fms ki domain to reconstitute PI turnover in the alpha R delta ki-2 transfectant provides evidence that the ki domain of the alpha PDGFR does not directly couple with this pathway. Taken together, all od these bindings imply that their ki domains have evolved to play very similar roles in the known signaling functions PDGF and CSF-1 receptors.
Mol Cell Biol 1991 Jan
PMID:Deletion or substitution within the alpha platelet-derived growth factor receptor kinase insert domain: effects on functional coupling with intracellular signaling pathways. 170 11

We have established primary lines of fibroblasts from nasal polyp (NP) tissues as well as from normal nasal (NN) mucosa and have examined the ability of these cells to release hormone-like peptide messenger molecules (cytokines). Our results show that human upper airway fibroblasts release granulocyte/macrophage colony-stimulating factor (GM-CSF), granulocyte-CSF (G-CSF), and macrophage-CSF (M-CSF) in vitro. We also show that fibroblasts derived from NP tissue express the gene for GM-CSF at a higher level, and release the GM-CSF product in greater amounts, than NN fibroblasts. In addition, we have examined the ability of these fibroblasts and their conditioned medium (CM) to induce differentiation of human hemopoietic progenitor cells. After 7 d, cultures of these cells in RPMI-10% fetal bovine serum contained 5 +/- 2.5% (mean +/- SD) neutrophils. In contrast, culture of progenitor cells with fibroblasts resulted in significantly greater neutrophilic differentiation (18 +/- 4%). Culture in fibroblast-CM induced a similar degree of differentiation, and fibroblast-CM from NP fibroblasts elicited greater differentiation compared to CM from NN fibroblasts (17.5 +/- 3 versus 12 +/- 3%). The neutrophilic differentiation induced by fibroblast-CM can be fully inhibited by preincubating this CM with a monoclonal neutralizing antibody to human GM-CSF. Thus, our results demonstrate: (1) the ability of human upper airway fibroblasts to release GM-, G-, and M-CSF in vitro; (2) that fibroblasts derived from NP tissues express the gene and release the product GM-CSF at greater levels compared to NN fibroblasts; and (3) that fibroblast-derived GM-CSF causes neutrophilic differentiation of human hemopoietic progenitors.
Am J Respir Cell Mol Biol 1991 Jan
PMID:Neutrophilic differentiation induced by human upper airway fibroblast-derived granulocyte/macrophage colony-stimulating factor (GM-CSF). 170 52

We examined the ability of conditioned medium (CM) generated by human upper airway epithelial (Ep) cells from normal (NN) and inflamed, allergic rhinitis (AR) and nasal polyp (NP) tissues to induce monocytic differentiation of hemopoietic progenitors of the HL-60 myeloid leukemia cell line in vitro. In HL-60 cells cultured in RPMI with 10% FBS, there was differentiation to 0.4 +/- 0.4% monocytic cells. NN-, AR-, and NP-EpCM induced differentiation to 23 +/- 6%, 42 +/- 11%, and 71 +/- 10% monocytic cells, respectively. EpCM also induced isolated peripheral blood nonadherent mononuclear cells to express monocyte/macrophage-specific antigens as detected by immunohistochemistry using FMC-32 monoclonal antibodies (anti-CD14). We also examined the cytokine content of these EpCMs and found that they contained granulocyte/macrophage colony-stimulating factor (GM-CSF): 126 +/- 35, 198 +/- 22, and 489 +/- 118 pg/ml for NN-, AR-, and NP-EpCM, respectively. These CMs also contained granulocyte-CSF (G-CSF) and interleukin-6 (IL-6), but there were no significant differences between normal and inflamed tissue-derived cell supernatants. No macrophage-CSF (M-CSF) was detected in these EpCMs. Recombinant human GM-CSF, G-CSF, and IL-6, alone and in combinations, at doses similar to or greater than those found in the EpCMs, did not induce comparable monocytic differentiation of HL-60 cells. Preincubation of the EpCM with neutralizing anti-GM-CSF, anti-G-CSF, or anti-IL-6 antibodies did not significantly inhibit the monocytic differentiation induced by the EpCM.(ABSTRACT TRUNCATED AT 250 WORDS)
Am J Respir Cell Mol Biol 1991 Mar
PMID:Monocyte-macrophage differentiation induced by human upper airway epithelial cells. 170 10

A peptide antiserum (anti-A) directed to the intracellular, juxtamembrane region (residues 552 to 574) of the human colony-stimulating factor 1 receptor (CSF-1R) precipitated only ligand-activated, native receptors from solution but bound to unstimulated forms after their denaturation. Two peptide antisera (anti-KI1 and -KI2), directed to residues 679 to 700 and 701 to 721, respectively, in the CSF-1R kinase insert (KI) domain and including mapped sites of ligand-induced phosphorylation at Tyr-699 and Tyr-708, bound at least 80% of the receptor molecules expressed in either CSF-1-stimulated or unstimulated cells. Immune complexes formed with anti-KI1, anti-A, or a peptide antiserum to the CSF-1R carboxyl terminus (anti-C-ter) coprecipitated CSF-1R complexed to a phosphatidylinositol 3-kinase (PtdIns 3-K) from CSF-1-stimulated cells, whereas anti-KI2 serum did not. In an in vitro assay, binding of CSF-1R to PtdIns 3-K required receptor tyrosine phosphorylation but not CSF-1R-mediated phosphorylation of the lipid kinase, and the association was specifically blocked by anti-KI2 or antibodies to phosphotyrosine. Neither anti-KI1, anti-A, nor anti-C-ter serum inhibited binding. We conclude that (i) only a minority of ligand-activated receptors form a stable complex with PtdIns 3-K in vivo, (ii) efficient binding of the lipid kinase requires receptor tyrosine phosphorylation within the CSF-1R KI domain, and (iii) a region within the KI domain defined by residues 701 to 721 at least partially overlaps the PtdIns 3-K binding site.
Mol Cell Biol 1991 May
PMID:Peptide antisera to human colony-stimulating factor 1 receptor detect ligand-induced conformational changes and a binding site for phosphatidylinositol 3-kinase. 170 91

One of the hallmarks of the granulomatous response to infection is the formation of multinucleated giant cells (MGC.) In an effort to study MGC, we examined the fusion-promoting effects of a variety of stimulating factors on human peripheral blood monocytes cultured on plastic surfaces in serum-supplemented media. MGC formation was minimally to moderately enhanced by interferon-gamma (IFN-gamma), interleukin (IL)-3, granulocyte/macrophage colony-stimulating factor (GM-CSF), 1,25-dihydroxycholecalciferol (1,25-(OH)2D3), retinoic acid (RA), and IL-6. IL-4 (which has been reported to promote MGC formation from murine macrophages) had an inhibitory effect. IFN-gamma was not required for MGC formation but it significantly increased the fusion-promoting activity of GM-CSF, 1,25-(OH)2D3, RA, and IL-6, IL-3, a hematopoietic growth factor, has been recently shown to induce osteoclast formation from murine bone marrow mononuclear cells. The most striking effect was seen with the combination of IL-3 and IFN-gamma. Fusion index is defined as a percentage of nuclei found within MGC, and an index of 67% at 1 wk was found. The formation of some very large cells with 50 to 100 nuclei was noted. Both Langhans' and foreign-body type cells were seen. Transmission electron micrographs clearly demonstrate the absence of plasma membrane between nuclei. Induction of MGC from peripheral human blood monocytes by IL-3 and IFN-gamma provides an in vitro system for the study of the formation and function of these cells.
Am J Respir Cell Mol Biol 1992 Jan
PMID:Induction of multinucleated giant cell formation from in vitro culture of human monocytes with interleukin-3 and interferon-gamma: comparison with other stimulating factors. 172 95

Cultured human bronchial epithelial cells constitutively produce granulocyte/macrophage colony-stimulating factor (GM-CSF). An upregulation of the synthesis and release of GM-CSF from those cells might contribute to the persistence of infiltration and local activation of inflammatory cells in some inflammatory diseases of the airways, such as asthma. Increased levels of immunoreactive and biologically active interleukin-1 (IL-1) have been identified in the airway secretions of asthmatic patients, together with an increase in GM-CSF contents. As IL-1 is known to upregulate GM-CSF production in many cell populations, in this study we investigated the ability of IL-1 to bind to specific receptors on bronchial epithelial cells and promote GM-CSF synthesis and release. Bronchial epithelial cells possessed specific single-class surface receptors for recombinant IL-1. The addition of exogenous IL-1 led to a dose-dependent increase in the accumulation of GM-CSF mRNA and release of immunoreactive GM-CSF to the culture medium. Release of IL-1 in the bronchial mucosa during allergic and nonallergic responses may lead to enhanced GM-CSF synthesis and release by epithelial cells, thus promoting airway inflammation.
Am J Respir Cell Mol Biol 1991 Jun
PMID:Interleukin-1 binds to specific receptors on human bronchial epithelial cells and upregulates granulocyte/macrophage colony-stimulating factor synthesis and release. 182 52

Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) is known as an inducer of proliferation and functional activation of myeloid cells. This study was carried out to characterize the effect of purified recombinant human GM-CSF (rhGM-CSF) on induction of TGF-alpha in macrophages. Using Northern blot analysis and immunoassays, we show here that rhGM-CSF markedly stimulates production of TGF-alpha messenger RNA and protein in normal tonsil macrophages. The findings are consistent with macrophages being a normal inducible source of TGF-alpha which may be an important mediator of various activities of GM-CSF both in hematopoietic and non-hematopoietic cells.
Cell Mol Biol 1991
PMID:Recombinant human granulocyte macrophage colony-stimulating factor (rhGM-CSF) induces human macrophage production of transforming growth factor-alpha. 193 15

Nasal polyposis is a chronic inflammatory condition of the upper airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. Granulocyte/macrophage colony-stimulating factor (GM-CSF) is a cytokine with powerful biologic effects including the regulation of survival, proliferation, and activation of granulocytes as well as differentiation of hemopoietic cells. To examine the potential role of GM-CSF in the pathogenesis of this condition, we investigated gene expression and production of GM-CSF in nasal polyp tissues as well as in the normal nasal mucosa. Immunoreactive GM-CSF was detected by enzyme-linked immunosorbent assay in the 24-h supernatant of nasal polyp tissues placed in culture. By Northern blot analysis and Southern blot analysis following a reverse-transcription polymerase chain reaction using a human GM-CSF cDNA probe, we detected GM-CSF mRNA in nasal polyp tissues, as well as in the tissue from a patient with allergic rhinitis, but not in the normal nasal mucosa. By in situ hybridization using the same probe, cells expressing mRNA specific for GM-CSF were observed in nasal polyp tissues and in the allergic nasal mucosa. In addition, by the combination of in situ hybridization and counterstaining with chromotrope 2R, we demonstrated that approximately 30% of eosinophils infiltrating the polyp tissue express the GM-CSF gene. These results suggest a novel mechanism by which eosinophils may contribute to the pathogenesis of chronic inflammatory diseases such as nasal polyposis, allergic rhinitis, and, by implication, asthma.
Am J Respir Cell Mol Biol 1991 Dec
PMID:Granulocyte/macrophage colony-stimulating factor (GM-CSF) gene expression by eosinophils in nasal polyposis. 195 76

Accumulation of eosinophils in the bronchial tissue occurs in a variety of inflammatory disorders of the human airway. We asked whether airway epithelial cells released factors that could influence eosinophil survival and thus contribute to accumulation of these cells in the tissues. Using conditioned medium (CM) generated from cultured human bronchial epithelial cells (HBEC), we examined the in vitro survival of eosinophils isolated from human peripheral blood. When cultured in control medium, more than 90% of the eosinophils were dead by day 4. In contrast, culture in HBEC-CM resulted in dose-dependent survival at day 6 of 69 +/- 9.4%, 40.5 +/- 5.9%, and 25 +/- 2% viability with 2, 0.5, and 0.1% HBEC-CM, respectively (n = 4). Granulocyte/macrophage colony-stimulating factor (GM-CSF) was detected in the HBEC-CM by enzyme-linked immunosorbent assay at levels of 22 to 48 pg/ml. Furthermore, preincubation of the HBEC-CM with a neutralizing monoclonal antibody to human GM-CSF completely inhibited this increased survival of eosinophils. Because corticosteroids are potent eosinopenic agents, we also examined the effects of the synthetic steroid budesonide on this system. Budesonide inhibited both spontaneous and interleukin-1 (IL-1)-induced GM-CSF production by cultured HBEC. In addition, preincubation of eosinophils with budesonide caused marked abrogation of the survival induced subsequently with either HBEC-CM or recombinant human GM-CSF. In summary, HBEC can support eosinophil survival via the elaboration of GM-CSF and thus may contribute to the local control of inflammatory cell accumulation. Steroids may modulate this process both by inhibiting cytokine production from HBEC and by a direct effect on eosinophils, preventing their response to cytokines.
Am J Respir Cell Mol Biol 1991 Jun
PMID:Promotion of eosinophil survival by human bronchial epithelial cells and its modulation by steroids. 205 93

Ligand-induced tyrosine phosphorylation of the human colony-stimulating factor 1 receptor (CSF-1R) could involve either an intra- or intermolecular mechanism. We therefore examined the ability of a CSF-1R carboxy-terminal truncation mutant to phosphorylate a kinase-defective receptor, CSF-1R[met 616], that contains a methionine-for-lysine substitution at its ATP-binding site. By using an antipeptide serum that specifically reacts with epitopes deleted from the enzymatically competent truncation mutant, cross-phosphorylation of CSF-1R[met 616] on tyrosine was demonstrated, both in immune-complex kinase reactions and in intact cells stimulated with CSF-1. Both in vitro and in vivo, CSF-1R[met 616] was phosphorylated on tryptic peptides identical to those derived from wild-type CSF-1R, suggesting that receptor phosphorylation on tyrosine can proceed via an intermolecular interaction between receptor monomers. When expressed alone, CSF-1R[met 616] did not undergo ligand-induced down modulation, but its phosphorylation in cells coexpressing the kinase-active truncation mutant accelerated its degradation.
Mol Cell Biol 1990 Apr
PMID:Ligand-induced phosphorylation of the colony-stimulating factor 1 receptor can occur through an intermolecular reaction that triggers receptor down modulation. 215 38


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