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)

The ability of cyclosporine (CSA) and FK506 to inhibit cytokine production by factor-dependent murine mast cell lines was investigated. The mast cell clone, MC/9, and two mast cell lines, MCIII and MCVI, were stimulated to produce cytokines with phorbol myristate acetate plus the calcium ionophore A23187. The production of cytokines by stimulated mast cells cultured in the presence or absence of drug was monitored by bioassay of culture supernatants for induction of proliferation by factor-dependent cell lines and inhibition of these responses by neutralizing monoclonal antibodies. Both CSA and FK506 inhibited mast cell cytokine production at concentrations comparable to those observed with T cells. However, the degree of inhibition of cytokine production varied among the mast cell lines as well as between different cytokines produced by a given mast cell line. For example, CSA completely inhibited interleukin-2 (IL-2), IL-3, IL-4 and granulocyte-macrophage colony stimulating factor secretion by all three lines, with the exception that IL-2/IL-4 production by MCIII was partially resistant to inhibition by CSA. Similarly, FK506 completely inhibited cytokine production by MC/9, partially inhibited cytokine production by MCIII and had differential effects on IL-3/granulocyte-macrophage colony-stimulating factor and IL-2/IL-4 production by MCVI. Consistent with their ability to selectively inhibit cytokine gene transcription in T cells, neither CSA nor FK506 inhibited factor-dependent proliferation by these mast cell lines. In view of the putative role of cytokines in inflammation and late phase asthmatic reactions, these observations may be of particular significance in development of methods of pharmacologic intervention.
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PMID:Cyclosporine and FK506 inhibition of murine mast cell cytokine production. 137 Nov 58

The therapeutic efficacy of interleukin-2 (IL-2) in the treatment of cancer has been limited by a "vascular leak syndrome" and related toxicities. To better understand the pathophysiology of the "vascular leak syndrome," we tested a hypothesis that mast cell degranulation mediated the acute increase in microvascular protein leakage seen immediately following IL-2 administration. After the cremaster muscle was prepared for intravital microscopy, anesthetized Sprague-Dawley rats were injected with fluorescein isothiocyanate-labeled albumin for fluorescent microscopy. Animals were treated by the intravenous injection of IL-2 (1 x 10(6) U/kg) (n = 6), the control IL-2-vehicle (n = 5), or IL-2 (1 x 10(6) U/kg) after mast cell degranulation with compound 48/80 (n = 6). Relative interstitial fluorescent intensity was quantitated by a computerized image analysis system as an index of microvascular protein leakage. IL-2 acutely induced protein leakage from the microcirculation. Mast cell degranulation with 48/80 prior to IL-2 treatment prevented protein leakage, but did not alter IL-2-induced leukocyte-endothelial adherence. These data suggest that mast cell-mediated events may be responsible for the acute increase in microvascular permeability seen with IL-2 administration and that leukocyte-endothelial adherence alone is not solely responsible.
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PMID:Mast cell degranulation inhibits IL-2-induced microvascular protein leakage. 161 9

Interleukin-2-dependent pathways of lymphocyte activation were investigated in canine peripheral blood lymphocytes (PBL) following stimulation with T-cell mitogens including phytohemagglutinin, phorbol ester (TPA), calcium ionophore (ionomycin), and human recombinant interleukin-2 (hrIL-2). The ability of the stimulated cells to produce interleukin-2 (IL-2) was determined using murine indicator cell lines. IL-2 receptor expression by mitogen-stimulated canine PBL was confirmed by the binding of hrIL-2 with high affinity, and with characteristics comparable to those of the human and murine IL-2 receptor. Examination of serum and PBL from two dogs that were treated with hrIL-2 and human recombinant tumor necrosis factor for systemic mast cell tumors showed that in one dog, IL-2 could be measured in the serum. Concurrently, the in vitro mitogenic response of this dog's PBL to hrIL-2 occurred earlier, possibly reflecting an increase in the relative number of IL-2-responsive cells within the PBL population.
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PMID:Immunophysiological studies of interleukin-2 and canine lymphocytes. 163 72

Clonal lines of mouse inducer ly1+ly2- inducer T-lymphocytes that depend for growth upon interleukin-2 have been demonstrated to produce a factor that stimulates colony formation by bone marrow granulocyte-macrophage (GM-CFUc) progenitor cells and replication of factor-dependent mast cell/basophil and multipotential hematopoietic cell lines in vitro. The molecularly cloned and expressed gene product for this growth factor demonstrates the following activities in vitro: using fresh bone marrow or purified subpopulations of nonadherent cells from murine continuous bone marrow cultures as target cells: stimulation of colony formation by GM-CFUc, mast cell progenitor cells, multipotential granulocyte/erythroid/megakaryocyte/macrophage progenitor cells (CFU-GEMM) colonies, erythroid progenitor cells forming macroscopic bursts (BFUe), and megakaryocyte progenitor cells (CFU-mega). The gene product also supports growth of previously reported mast cell growth-factor-dependent cell lines and several classes of interleukin-3 (IL-3)-dependent hematopoietic progenitor cell lines that are multipotential (neutrophil/basophil/eosinophil or neutrophil/basophil/erythroid); or committed to granulocyte-macrophage, or mast cell/basophil differentiation. The gene product does not detectably support replication of IL-2-dependent murine T-cell lines. The biologic activity of the gene product was inhibited greater than or equal to 90% by rabbit antisera prepared against purified interleukin-3. The data indicate that this T-cell derived lymphokine gene product is biologically very similar to interleukin-3.
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PMID:Molecularly cloned and expressed murine T-cell gene product is biologically similar to interleukin-3. 258 Jul 30

The interleukin-2-dependent mouse natural killer (NK) cell line NKB61A2 concomitantly exhibits NK and natural cytotoxic (NC) activities. This was determined by the cells' ability to lyse both the NK-sensitive YAC-1 lymphoma and the NC-sensitive WEHI-164 fibrosarcoma cell lines in a 4- and 18-hour 51Cr release assay, respectively. Cell-free supernatant from NKB61A2 cells grown in culture for 48 h had substantial lytic activity against WEHI-164. The mouse mast cell line PT18-A17 and the rat basophilic leukemia cell line RBL-2H3, which both express NC activity, also produced a soluble factor during culture which lysed WEHI-164 cells. This activity was increased in the basophilic/mast cells by crossbridging the surface IgE receptors. Similar results were obtained by triggering the basophilic NC cells with the calcium ionophore ionomycin and the tumor promoter phorbol-12-myristate-13-acetate (PMA). Such triggering of NKB61A2 cells, however, did not significantly increase their NC activity. Interestingly, both ionomycin and PMA had an inhibitory effect on the NK activity of NKB61A2. Recently it has been found that tumor necrosis factor (TNF) is a major mediator of NC activity. To determine if the soluble factor responsible for the NC activity of the NK clone was related to TNF, a rabbit polyclonal antiserum to mouse TNF was tested against the cell-free culture medium of NKB61A2, PT18-A17, RBL-2H3 and murine recombinant TNF (Mu-rTNF). The lytic activity of the culture medium from all these cells and the Mu-rTNF control was abrogated by this antibody. These data suggest that the murine cell line NKB61A2 has both NK and NC activities and that the NC activity is due to a factor immunologically similar to TNF. In addition, the enhancement of NC activity in the NK cell line is apparently under control by a separate pathway, different from that in the basophilic cells.
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PMID:Natural cytotoxic activity in a cloned natural killer cell line is mediated by tumor necrosis factor. 276 50

Colonies of cells termed 'giant granular leucocytes' (GGL) displaying natural killer (NK) activity were generated in cell culture. The prominent feature of these cells was the formation of large cytoplasmic pool--the 'theca'--filled up with glycogen. This was demonstrated by the strong positive red staining of the theca with periodic acid Schiff reagent (PAS) which was abolished by prior treatment with amylase. Two different procedures were employed for obtaining colonies of NK-GGL. In the first, mice were injected either with killed Corynebacterium parvum or with killed Bordetella pertusis preparations and their mesenteric lymph-node cells were grown on syngeneic X-irradiated embryonic skin fibroblast monolayers. At the foci of GGL formation the fibroblasts were killed and the cleared areas thus formed were populated by adherent GGL. In the second procedure, supernates from rat or mouse spleen cultures stimulated with concanavalin A (Con A)--Interleukin-2 (IL-2)--were added to cultures of spleen and lymph-node cells prepared from either ordinary or from athymic nude mice. Richest GGL populations developed when rat IL-2 was added to cells of nude mice. Mouse IL-2 was less consistent. With nude mouse cells it stimulated, either mast cells or GGL, or both; rat IL-2 did not stimulate mast-cell differentiation in nude mouse cultures. In contrast, supernates from lymph-node cell cultures prepared from mice infected with Schistosoma mansoni. Mucosal mast cell-stimulating factor (MMSF) stimulated the formation of colonies of mast cells but not GGL. When MMSF was added as late as 23 days, colonies of young mast cells appeared and mast cells progressively increased in number. When rat IL-2 was added to such mature mast-cell cultures on the 30th day, colonies of cytolytic-GGL appeared. These observations indicate that precursors of mast cells and GGL persist in the cultures and preserve their potential to be stimulated by T-cell factors. GGL-NK cells developed on monolayers prepared from whole embryos released substance that displayed morphology and staining characteristic of mucus. Evidence gathered from in-vitro and in-vivo studies links the in-vitro GGL-NK cells to motile cells that inhabit the mucosal epithelium. Based on the observations, a hypothesis on the function of NK cytotoxicity is brought forward. It proposes the replacement of ordinary epithelial cells, which are killed during a proliferative and differentiative response of other cells at the onset of an infection course.
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PMID:Murine interleukin-2 generates glycogen-rich and mucus-secreting NK cells. 619 79

Although the immune responses to intestinal nematode infection have been well studied and have been shown to be strongly driven by Th2-associated cytokines in mice, such information has been limited with respect to rats. We investigated changes in levels of the mRNAs encoding interleukin-2 (IL-2), IL-3, IL-4, IL-5, IL-10, and gamma interferon in the mesenteric lymph nodes of rats infected with Nippostrongylus brasiliensis by reverse transcription-PCR in comparison with immunoglobulin E (IgE)/IgG2a antibody, eosinophil, basophil, and mucosal mast cell responses. In the two rat strains used, Brown Norway and Fischer-344, which show different responses to allergens, serum IgE increased to much higher levels in the former than in the latter 2 weeks after infection. Intestinal mastocytosis was observed much earlier and more intensely in Brown Norway rats than in Fischer-344 rats, but the degrees of peripheral eosinophilia and basophilia did not differ between the two strains. In both strains, IL-3, IL-4, and IL-5 mRNA expression increased and peaked around 7 to 14 days after infection, while expression of IL-2, IL-10, and gamma interferon mRNAs did not change notably throughout the experimental period. The highest IL-4 mRNA expression was observed slightly earlier in Brown Norway than in Fischer-344 rats, but levels of IL-3 and IL-5 mRNAs peaked synchronously in both strains. The amounts of mRNAs encoding these three cytokines were always higher in Brown Norway than in Fischer-344 rats. It is suggested that in rats, Th2 or Th2-like cells are also induced after nematode infection, and IgE elevation is mainly related to increased IL-4 gene expression.
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PMID:Cytokine mRNA expression profiles in rats infected with the intestinal nematode Nippostrongylus brasiliensis. 759 Nov 19

Nuclear factor of activated T-cells (NFAT) is a transcriptional activator that binds to the interleukin-2 promoter and is believed to be responsible for T-cell-specific interleukin-2 gene expression. Here we demonstrate using electrophoretic mobility shift assays that nuclear NFAT can be induced in the rat basophilic leukemia (RBL-2H3) mast cell line and rat bone marrow-derived mast cells upon cross-linkage of the high affinity receptor (Fc epsilon RI) for immunoglobulin E (IgE). Receptor-dependent activation of NFAT was mimicked by the combination of the protein kinase C activator phorbol myristate acetate and the calcium ionophore ionomycin. The induced binding activity was specific for the NFAT recognition motif because competition with nonradioactive NFAT oligonucleotide abolished the DNA binding activity, whereas nonradioactive oligonucleotides recognized by the transcription factors NF kappa B, glucocorticoid receptors, and TFIID did not. An oligonucleotide representing the AP-1 recognition sequence also blocked the NFAT DNA binding activity, as did a combination of anti-Fos and anti-Jun antibodies. Using electrophoretic mobility shift assays, AP-1-binding proteins were found to be induced in RBL-2H3 cells under the same conditions as was the NFAT binding activity. Together these data suggest that the NFAT complex in mast cells contains Fos and Jun proteins as does NFAT in T-cells. The appearance of nuclear NFAT binding activity was dependent in part upon calcium mobilization, as buffering the antigen-induced calcium rise with intracellular BAPTA strongly inhibited NFAT activation. Prevention of calcium influx with external EGTA also inhibited NFAT activation, indicating that release of calcium from internal stores was insufficient for sustained activation of mast cell NFAT. Cyclosporin A, a potent inhibitor of the calmodulin-dependent phosphatase calcineurin, blocked the induction of NFAT-DNA binding activity, implicating calcineurin as a key signaling enzyme in this pathway. These results suggest that NFAT is present in the mast cell line RBL-2H3 and in primary bone marrow-derived mast cells, is similar in subunit composition to the T-cell NFAT, and may play a role in calcium-dependent signal transduction in mast cells.
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PMID:Fc epsilon RI-mediated induction of nuclear factor of activated T-cells. 760 2

1. We determined the effect of cyclosporine A (CsA) treatment on mast cell degranulation and lung resistance (R(L)) in vivo, and tracheal smooth muscle (TSM) contraction ex vivo after antigen challenge in sensitized cats. We also determined the direct effects of addition of CsA to the tissue bath on antigen-induced responses of TSM in vitro. 2. Cats (n=10) were sensitized by i.m. injection of Ascaris suum antigen (AA); 5 cats (CsA+) received CsA twice daily for 2 weeks before acute antigen challenge in doses sufficient to suppress interleukin-2 secretion from feline peripheral blood mononuclear cells ex vivo. 3. Lung resistance increased comparably within 10 min of exposure to AA (P<0.03). Histamine content in bronchoalveolar lavage fluid from both groups increased comparably within 30 min of antigen challenge, from undetectable levels to 542+/-74 pg ml(-1) post AA for CsA+ and from 74+/-19 pg ml(-1) at baseline, to 970+/-180 pg ml(-1) post AA CsA- (P<0.05; P=NS vs CsA+). 4. In excised TSM, active tension elicited by exposure to AA in vitro was 107+/-38% KCl in the CsA+ group vs 144+/-56% KCl in the CsA- group (P=NS). However, contraction of TSM (n=4) harvested from both groups was abolished or greatly diminished after AA challenge when tissues were pre-incubated with 1 microM CsA in vitro (8+/-8% KCl, P<0.05 vs CsA+ and CsA-). This was associated with inhibited release of 5-hydroxytryptamine into the organ bath fluid of tissues treated with CsA in vitro only. 5. We demonstrated that CsA treatment in vivo does not inhibit the early phase asthmatic response or mast cell degranulation following antigen challenge in sensitized cats. Additionally, the effects of CsA on mast cell function ex vivo do not reflect lack of effects of CsA on mast cell function in vivo in this animal model of atopic asthma.
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PMID:Differential effects of cyclosporine A after acute antigen challenge in sensitized cats in vivo and ex vivo. 955 5

Translation is regulated predominantly by an interplay between cis elements at the 3' and 5' ends of mRNAs and trans-acting proteins. Cyclosporin A (CsA), a calcineurin antagonist and blocker of interleukin-2 (IL-2) transcription in T cells, was found to inhibit translation of IL-3 mRNA in autocrine mast cell tumor lines. The mechanism involved ribosome-associated poly(A) shortening and required an intact AU-rich element in the 3' untranslated region. FK506, another calcineurin inhibitor, shared the effect. The translational inhibition by CsA was specific to oncogenically induced lymphokines IL-3 and IL-4 but not to IL-6, c-jun, and c-myc, which are expressed in the nonmalignant precursor cells. Furthermore, no translational down-regulation of the mRNA was observed in IL-3-transfected precursor cells. These data suggest that translational silencing is associated with the tumor phenotype.
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PMID:Cyclosporin A promotes translational silencing of autocrine interleukin-3 via ribosome-associated deadenylation. 985 12


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