Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mice harboring a mutation in the microphthalmia (mi) gene display a variety of abnormalities, including microphthalmia, depletion of skin melanocytes, deafness, a defect in osteoclasts, and a major decrease in mast cell number and function. However, despite the possible critical role played by this protein in mast cell development and function, characterization of its mRNA and protein synthesis in these cells has not yet been performed. In this study, we investigated the regulation of the synthesis of mi in murine mast cells activated by various physiologic stimuli. Using a specific rabbit polyclonal anti-mi antibody, we found that interleukin-3, interleukin-4, or aggregation of the mast cell high-affinity receptor for IgE (Fc epsilonRI) induced the synthesis of mi protein in these cells. None of these stimuli significantly affected the level of mi mRNA in the mast cells at any of the time points tested. Also, using this specific anti-mi antibody, an increase in mi protein synthesis was shown during differentiation of mast cells from their bone marrow cell precursors. Moreover, a complex containing mi bound to upstream stimulating factor 2 was detected only in activated mast cells. We conclude that the regulation of mi expression is on the translational level. Thus, stimulation of mast cells by a variety of stimuli elicits a signaling pathway that regulates mi expression.
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PMID:Microphthalmia (mi) in murine mast cells: regulation of its stimuli-mediated expression on the translational level. 910 21

Mast cells are bone marrow-derived, ubiquitous connective tissue resident cells. However, their mechanisms of migration, the distribution of immature and mature cells and their interaction with other inflammatory cells are largely unclarified. Possibly, beta 2-integrins play an important role in these processes. In the present investigation, the authors studied the expression and regulation of the beta 2-integrins LFA-1 (CD11a/CD18), Mac-1 (CD11b/CD18), p150,95 (CD11c/CD18) and of the LFA-1/Mac-1 counter-receptor intercellular adhesion molecule-1 (ICAM-1; CD54) on leukaemic (HMC-1 cell subclone 5C6) and on normal mature human skin mast cells. The HMC-1 cells clearly expressed CD11a, CD18 and CD54, while expression of CD11b and CD11c was low. The apparent molecular weights were 180 kDa (CD11a), 95 kDa (CD18) and 90 kDa (CD54) as determined by Western blot analysis. Phorbol myristate acetate (PMA) induced a time- and dose-dependent up-regulation of CD11a, CD11b, CD11c, CD18 and CD54 that was inhibited by cycloheximide, suggesting a dependence on de novo protein synthesis. Enhanced expression of CD11a, CD11b, CD11c and CD18 could also be confirmed at the gene level as demonstrated by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Increased expression of LFA-1/ICAM-1 in response to PMA was accompanied by strong enhancement of homotypic cell aggregation, suggesting that newly synthesized LFA-1/ICAM-1 is functionally active. In order to determine a physiologically relevant way of mast cell beta 2-integrin modulation, several cytokines and chemotactic mediators (interleukin-4, IL-4; nerve growth factor beta, NGF beta; C5a; and leukotriene B4, LTB4) were tested for their influence on adhesion molecule cell surface density. Only LTB4 was shown specifically to up-regulate CD11a and CD18, but not CD11b or CD11c. The presence of CD11a, CD11c and CD18 could be confirmed on a low percentage of normal skin mast cells by immunofluorescence, using a double staining technique. In comparison to normal skin, a significantly higher percentage of CD18+ mast cells was found in inflammatory dermatoses such as psoriasis vulgaris, atopic dermatitis and lichen planus. Therefore, mast cell beta 2-integrins possibly play an important role during homing of immature mast cells as well as during the interaction of activated mast cells with other inflammatory cells.
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PMID:Human leukaemic (HMC-1) and normal skin mast cells express beta 2-integrins: characterization of beta 2-integrins and ICAM-1 on HMC-1 cells. 916 89

Interleukin-4 contributes to expulsion of certain gastrointestinal parasites and causes intestinal mucosal mastocytosis. Because mast cell-derived mediators are spasmogenic, potentially causing parasitic expulsion, we investigated the effect of interleukin-4 on smooth muscle and the mast cell and mediator dependency of this effect. BALB/c, mast cell-deficient W/Wv mice, 5-lipoxygenase-efficient mice, and their littermate controls were injected with interleukin-4-anti-interleukin-4 antibody complexes that chronically increase serum interleukin-4 levels. Mid-small intestinal segments, hung longitudinally in organ baths, were stimulated electrically or by agonists. The cholinergic response to electrical field stimulation was significantly increased by interleukin-4 treatment in BALB/c but not W/Wv mice. The enhanced cholinergic contraction was not due to increased acetylcholine responsiveness but was dependent on leukotriene D4, since it was reversed by leukotriene D4 receptor antagonism, and not observed in 5-lipoxygenase knock-out mice. Leukotriene D4 responsiveness was unaffected by interleukin-4 treatment. We conclude that interleukin-4 amplifies cholinergic excitation through a mast cell and leukotriene D4-dependent mechanism.
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PMID:Interleukin-4 modulates cholinergic neural control of mouse small intestinal longitudinal muscle. 917 23

We have previously shown that mouse bone marrow-derived mast cells (BMMC) can process and present immunogenic peptides to CD4 T cells. Here, we report on a T cell-dependent MHC class II-mediated mast cell activation resulting in IL-4 transcription and protein release. Presentation of optimal doses of ovalbumin peptide 323-339 resulted in IL-2 production by a specific T cell hybridoma and increase in IL-4 mRNA transcription in mast cells. IL-4 mRNA transcription increased by 200-fold in mast cells treated in IL-3/IL-4/granulocyte-macrophage colony-stimulating factor (high presenters) whereas only a tenfold increase or no increase were obtained with IL-3/IL-4/IFN-gamma- or IL-3-treated mast cells (low presenters), respectively. Induction of IL-4 mRNA transcription in purified mast cells by direct ligation of MHC class II molecules, using anti-I-A and anti-I-E-coated beads, indicates that MHC class II molecules are critical in this signaling pathway. However, when compared to T cells, anti-MHC class II-coated beads were less efficient, indicating a potential role of accessory molecules in this mast cell activation process. IgE-independent IL-4 production by mast cells as a result of cognate interaction with CD4 T cells could be critical for the development of type 2 responses. This novel mechanism may contribute to the induction and/or amplification of specific IgE-mediated allergic responses.
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PMID:IL-4 mRNA transcription is induced in mouse bone marrow-derived mast cells through an MHC class II-dependent signaling pathway. 954 79

An analysis was conducted of the cytokine profile and inflammatory response in oxazolone sensitized mouse skin. Following exposure to oxazolone, the intralesional production of inflammatory cytokines was demonstrable at the levels of both mRNA and protein. An initial challenge led to a transient increase in tumor necrosis factor-alpha production followed predominately by the T helper (Th)1 cytokine, interferon-gamma. There was a minimal production of interleukin-4, a Th2 cytokine. Continued exposure to oxazolone led to a downregulation of interferon-gamma and an upregulation of interleukin-4 production. A strong relationship was found between interleukin-4 and the inflammatory response, as measured by ear thickness. Similar experiments conducted in mast cell-deficient mice revealed reduced neutrophil influx but only minor changes in cytokine profile. An irritant response induced by chronic exposure of mouse skin to phorbol ester did not reveal any significant interferon-gamma or interleukin-4 response but was characterized by a tumor necrosis factor-alpha response that correlated with the inflammatory response. These observations suggest that the major source of interferon-gamma and interleukin-4 in the oxazolone response may be the infiltrating lymphocytes; whereas the tumor necrosis factor-alpha may result from the local irritation seen with both oxazolone and phorbol ester. At the end of 4 wk of chronic exposure to oxazolone, it was found that serum IgE levels had significantly increased. Histologic analysis of the skin lesion revealed that a mixed infiltrate including eosinophils developed upon repeat exposure to oxazolone. These findings are consistent with an early predominate Th1 response that is reduced and largely replaced with a Th2 response upon chronic T cell activation.
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PMID:Intralesional cytokines in chronic oxazolone-induced contact sensitivity suggest roles for tumor necrosis factor alpha and interleukin-4. 966 92

Upon infection with the cecum-dwelling nematode Trichuris muris, the majority of inbred strains of mice launch a Th2-type immune response and in doing so expel the parasite before patency. In contrast, there are a few mouse strains which develop a nonprotective Th1-type response resulting in a chronic infection and the presence of adult worms. Of the Th2 cytokines known to be associated with the resistant phenotype (interleukin-4 [IL-4], IL-5, IL-9, and IL-13), comparatively little is known about the contribution that IL-9 makes towards the protective immune response. In this study we demonstrate that IL-9 is expressed early during the Th2-type response and that its elevation in vivo results in the enhancement of intestinal mastocytosis and the production of both the immunoglobulin E (IgE) and IgG1 isotypes. In addition, elevated IL-9 levels in vivo facilitated the loss of T. muris from the intestine. That IL-9 is important in promoting worm expulsion was also seen following infection of IL-9-transgenic mice, which constitutively overexpress the cytokine. These animals displayed an extremely rapid, but immune mediated, expulsion of the parasite. Also evident in these animals was a pronounced intestinal mastocytosis, which was previously shown by us to be responsible for the expulsion of the related nematode Trichinella spiralis from these animals. Taken together with observations of IL-9 production following infection with other helminths, the results imply that IL-9 contributes to the general mast cell and IgE response characteristic of these infections and, more specifically, enhances resistance to T. muris.
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PMID:Interleukin-9 enhances resistance to the intestinal nematode Trichuris muris. 967 69

The increase in the amount of airway smooth muscle in the bronchial wall associated with asthma is partly due to hyperplasia. It is therefore important to determine which factors regulate growth and especially proliferation. In this study, we describe the effect of interleukin-4 (IL-4), a mast cell- and T lymphocyte-derived cytokine, on human airway smooth muscle proliferation as determined by [3H]thymidine uptake in the presence of fetal bovine serum (FBS), platelet-derived growth factor, basic fibroblast growth factor, and thrombin. IL-4 (5, 15, 50, and 150 ng/ml) significantly decreased 10% FBS-induced proliferation by 50, 73, 43, and 46%, respectively. The proliferative responses to platelet-derived growth factor (20 and 40 ng/ml), basic fibroblast growth factor (30 ng/ml), and thrombin (1 and 10 U/ml) were significantly reduced by 19, 21, 37, 36, and 57% respectively in the presence of 50 ng/ml of IL-4. We investigated the effect of IL-4 and other known inhibitors of smooth muscle proliferation, namely PGE2, heparin, and forskolin, on intracellular cAMP concentrations. IL-4 (50 ng/ml) and heparin (100 U/ml) did not alter intracellular cAMP levels when cells were treated with 1 or 10% FBS. PGE2 (1 microM) and forskolin (10 microM) significantly increased cAMP concentration above the control value in nonproliferating cells (1% FBS treated) by 7- and 37-fold, respectively. The effect of IL-4 (50 ng/ml), PGE2 (1 microM), and forskolin (10 microM) on cyclin D1 protein expression in 10% FBS-stimulated human airway smooth muscle cells was also examined. PGE2 and forskolin did not significantly inhibit cyclin D1 expression. However, IL-4 decreased cyclin D1 expression by 21%. These results provide evidence that IL-4 decreases human airway smooth muscle cell proliferation via a mechanism that is cAMP independent and mediated, in part, by a decrease in cyclin D1 protein expression.
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PMID:Interleukin-4 inhibits mitogen-induced proliferation of human airway smooth muscle cells in culture. 972 41

Using in situ hybridization and the reverse transcriptase polymerase chain reaction (RT-PCR) we show that messenger RNA for IL-4, IL-5 and tumor necrosis factor-alpha (TNF-alpha) is induced by cross-linkage of high-affinity Fc(epsilon) receptors (Fc(epsilon)RI) on human skin mast cells, but that only TNF-alpha mRNA is selectively induced by substance P. Skin mast cells were purified using the Percoll density technique. T cells were removed by serial negative selection using a CD2 monoclonal antibody (mAb) to achieve a final mast cell purity >95%. Purified mast cells were precultured with recombinant human stem cell factor (rhSCF; 10 ng/ml) and myeloma IgE (3 microg/ml) for 16 h before challenge with sheep polyclonal antihuman IgE antibody (anti-IgE; 1 or 10 microg/ml) in the presence of rhSCF (50 ng/ml). Using in situ hybridization, we demonstrated that IgE-dependent stimulation induces the expression of IL-4, IL-5 and TNF-alpha mRNA in skin mast cells. We have investigated the expression of IL-4, IL-5 and TNF-alpha mRNA by substance P, with the result that substance P, 0.003-30 microM, selectively induced TNF-alpha mRNA. However, substance P did not induce IL-4 mRNA and did not enhance IL-5 mRNA. Furthermore, we confirmed the release of TNF-alpha by substance P from skin mast cells using an ELISA technique. These findings demonstrate the capacity of human skin mast cells to transcribe IL-4, IL-5 and TNF-alpha by immunological activation and to transcribe and release TNF-alpha by substance P.
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PMID:Human skin mast cells produce TNF-alpha by substance P. 975 97

In this study, we have developed a method to obtain mast cells with connective tissue type mast cell (CTMC) characteristics directly from mouse bone marrow (BM) cells. BM cells were grown for 3 weeks in presence of interleukin-4 (IL-4) plus stem cell factor (SCF). SCF alone poorly supported growth and development of mast cells. IL-4 dose-dependently enhanced the expression of c-kit and high-affinity receptor for IgE (Fc(epsilon)RI) on the cell surface of SCF-cultured BM cells. Furthermore, cytoplasmic granulation and histamine synthesis of BM-derived mast cells were increased in presence of IL-4 and SCF. Histochemical staining demonstrated that granules were safranin positive. BM-derived mast cells could be activated for granule exocytosis (beta-hexosaminidase release) and lipid mediator generation (LTC4 production) via Fc(epsilon)RI after sensitization with IgE and subsequent crosslinking with multivalent antigen. In addition, mast cells derived from BM cells cultured with SCF plus IL-4 could be activated by substance P, a nonimmunologic stimulus, to release beta-hexosaminidase. The results presented indicate that IL-4 and SCF both have a prominent role in the development of mast cells from murine BM cells in vitro. Mast cells can directly be derived from BM cells in presence of SCF and IL-4 and the cultured cells show typical hallmarks of CTMC, indicating that precursor cells for CTMC may be present in BM. The described culture procedure may be useful to investigate the molecular aspects of the development of committed mast cell lineages.
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PMID:Stem cell factor and interleukin-4 induce murine bone marrow cells to develop into mast cells with connective tissue type characteristics in vitro. 1021 Mar 23

When mast cells are activated through their high affinity IgE receptors (FcepsilonRI), release of chemical mediators is followed by secretion of multiple cytokines. In this work, we report that IL-3-dependent mast cell line MC9 undergoes apoptosis when IL-3 is withdrawn. However, cross-linking of FcepsilonRI prevents apoptosis of MC9 by an autocrine mechanism, producing IL-3, IL-4, and GM-CSF. Although stimulated MC9 synthesizes mRNAs and proteins of these cytokines, secretion of endogenous IL-3 and GM-CSF is not enough for cell survival, whereas IL-4 itself does not have survival effect on MC9, but it induces cell aggregation by expressing LFA-1 and makes it reactive to endogenous growth factors. Addition of dexamethazone (DXM) to MC9 results in significant down-regulation of IL-4 mRNA in activated MC9. However, mRNA levels of IL-3 and GM-CSF are not changed by DXM. DXM also directly down-regulates the expression of ICAM-1 that is the high affinity ligand of LFA-1, by which the self-aggregation of MC9 is inhibited. Thus, glucocorticoids suppress autocrine survival of mast cells by inhibiting IL-4 production and ICAM-1 expression.
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PMID:Glucocorticoid suppresses autocrine survival of mast cells by inhibiting IL-4 production and ICAM-1 expression. 1022 60


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