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Sample records for mast cell-depleted rats

  1. Pavlovian Conditioning of Rat Mucosal Mast Cells to Secrete Rat Mast Cell Protease II

    NASA Astrophysics Data System (ADS)

    MacQueen, Glenda; Marshall, Jean; Perdue, Mary; Siegel, Shepard; Bienenstock, John

    1989-01-01

    Antigen (egg albumin) injections, which stimulate mucosal mast cells to secrete mediators, were paired with an audiovisual cue. After reexposure to the audiovisual cue, a mediator (rat mast cell protease II) was measured with a sensitive and specific assay. Animals reexposed to only the audiovisual cue released a quantity of protease not significantly different from animals reexposed to both the cue and the antigen; these groups released significantly more protease than animals that had received the cue and antigen in a noncontingent manner. The results support a role for the central nervous system as a functional effector of mast cell function in the allergic state.

  2. Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells

    SciTech Connect

    Fagan, D.L.

    1986-01-01

    The role of lysophosphatidic acid in mast cell response to antigen was investigated using an isolated rat serosal mast cell model. The cells were incubated with monoclonal murine immunoglobulin E to the dinitrophenyl hapten and prelabeled with /sup 32/P-orthophosphate or /sup 3/H-fatty acids. Lysophosphatidic acid was isolated form cell extracts by 2-dimensional thin-layer chromatography, and the incorporated radioactivity was assessed by liquid scintillation counting. Lysophosphatidic acid labeling with /sup 32/P was increased 2-4 fold within 5 minutes after the addition of antigen or three other mast cell agonists. Functional group analyses unequivocally showed that the labeled compound was lysophosphatidic acid. Lysophosphatidic acid synthesis was dependent on the activity of diacylglycerol lipase, suggesting formation from monoacylglycerol. In addition, the studies of lysophosphatidic acid synthesis suggest that the addition of antigen to mast cells may initiate more than one route of phospholipid degradation and resynthesis. Whatever the origin of lysophosphatidic acid, the results of this study demonstrated that lysophosphatidic acid synthesis is stimulated by a variety of mast cell agonists. Dose-response, kinetic, and pharmacologic studies showed close concordance between histamine release and lysophosphatidic acid labeling responses. These observations provide strong evidence that lysophosphatidic acid plays an important role in mast cell activation.

  3. Effect of methylmercury on the rat mast cell degranulation

    NASA Astrophysics Data System (ADS)

    Graevskaya, E. E.; Yasutake, A.; Aramai, R.; Rubin, A. B.

    2003-05-01

    Methylmercury is the well-known neurotoxicant as weil as a modulator of the immune system. We investigated the effects of MeHg on the rat mast cell degranulation induced by nonimmunological stimuli (the selective liberator of histamine, compound 48/80, and calcium ionophore A23187) both in vivo and in vitro. In 8, 12 and 15 days afterthe final administration of MeHg we observed the suppression of calcium ionophore A23187-and 48/80-induced histamine release, which enhanced with time. In experiments in vitro incubation of peritoneal mast cells with MeHg alone in the dose range 10^{-8} to 10^{-6} did not induce mast cell degranulation, however modified the activation of mast cells by compound 48/80, and calcium ionophore A23187. We observed activation of stimulated secretion by preliminary incubation with low dose of MeHg 10^{-8} M and inhibition by dose of MeHg 10^{-6} M. These results show that MeHg treatment can modify mast cell function in vivo and in vitro and provide insight into the understanding what role this cell has in the pathogenesis of Minamata disease-comlected disorders.

  4. Mast cell mediators and peritoneal adhesion formation in the rat.

    PubMed

    Langer, J C; Liebman, S M; Monk, P K; Pelletier, G J

    1995-09-01

    We have previously shown that mast cell stabilization attenuates peritoneal adhesion formation in the rat. The present study investigated the mechanism of this protection. Adhesions were created in weanling rats using cecal scraping and application of 95% ethanol. Rats received specific blockers for the mast cell products histamine, serotonin (5HT), leukotriene D4, and platelet activating factor intraperitoneally 30 min before laparotomy and at the time of abdominal closure. Control animals received saline. Adhesions were assessed blindly 1 week later using a standardized scale. Adhesion formation was not affected by histamine blockade using combined mepyramine and ranitidine, 5-HT1 blockade using methysergide, 5-HT3 blockade using ondansetron, leukotriene D4 blockade using MK-571, or platelet activating factor blockade using WEB-2086. However, blockade of the 5-HT2 receptor using ketanserin resulted in significant dose-dependent attenuation of adhesions compared to saline. These data suggest that mast cells mediate peritoneal adhesion formation in the rat through release of serotonin acting on 5HT2 receptors. Further understanding of this process may lead to new strategies for the prevention of postoperative adhesions.

  5. Protamine and mast-cell-mediated angiogenesis in the rat.

    PubMed Central

    Jakobsson, A.; Sörbo, J.; Norrby, K.

    1990-01-01

    Different doses of protamine sulphate (PS) given s.c. (at 12-h intervals) were tested for signs of non-specific toxicity measured as effect on body weight and small-gut proliferation as well as on mast-cell secretion and mast-cell-mediated mitogenesis in the mesenteric windows following i.p. injection of Compound 48/80, a potent mast cell secretagogue, in normal rats. In a non-toxic dose range, the effect of PS on mast-cell-mediated angiogenesis, effected by 48/80, was quantified as the number of vessels per mm of mesenteric window in histological sections at x 400. No intelligible dose-effect relationship was discernible between the dose of PS given and the effect on angiogenesis. Only in a tight interval, at 40 mg PS/kg but not at 20 or 60 mg PS/kg, was the angiogenesis statistically significantly suppressed. Hence, it was concluded that PS can be angiostatic but does not exert a more general angiostatic effect in the autogenous systems used. PMID:1691920

  6. Isolation and characterization of hepatic mast cells from cholestatic rats

    PubMed Central

    Hargrove, Laura; Graf-Eaton, Allyson; Kennedy, Lindsey; Demieville, Jennifer; Owens, Jennifer; Hodges, Kyle; Ladd, Brittany; Francis, Heather

    2016-01-01

    Mast cells (MCs) are immune cells that release histamine and other mediators. MC number increases after bile duct ligation (BDL) and blocking mast cell-derived histamine decrease biliary proliferation. We aimed to isolate and characterize MCs from cholestatic livers. Rats were subjected to BDL starting at 6 hrs and up to 14 days. MC infiltration was evaluated by toluidine blue. BDL rats were perfused using standard collagenase perfusion. Following enzymatic digestion, tissue was passed through a fine gauge needle. Suspensions were incubated with MAb AA4, washed and incubated with goat anti-mouse coated Dynal® beads. MCs were stained with toluidine blue, and in isolated MCs, the expression of FCεRI and MC proteases was measured. The expression of histidine decarboxylase, histamine receptors, VEGF-receptors and TIE 1 and 2 was evaluated by qPCR. Histamine and VEGF-A secretion was measured in MC supernatants. MC purity was evaluated by CK-19, CK-8, albumin, VAP-1 and α-SMA expression. In vitro, cholangiocytes and HSCs were treated with isolated MC supernatants from BDL rats treated with either NaCl or cromolyn sodium (to block MC histamine release) and biliary proliferation and hepatic fibrosis were measured. MCs infiltrate the liver and surround bile ducts starting at day 2. We isolated a virtually pure preparation of mature, functional MCs. TEM images reveal distinct secretory granules and isolated MCs secrete histamine. MCs express FCεRI, chymase, tryptase, RMCPI and RMCPII, but were virtually void of other cell markers. Biliary proliferation and fibrosis increased following treatment with MC supernatants from BDL rats + NaCl and these parameters decreased in cells treated with MC supernatants from BDL + cromolyn sodium. In conclusion, we have isolated and characterized MCs from cholestatic livers. MCs regulate cholestatic liver injury and hepatic fibrosis. This tool provides a better understanding of the paracrine influence of mast cells on biliary

  7. [³H]serotonin release assay using antigen-stimulated rat peritoneal mast cells.

    PubMed

    Skaper, Stephen D; Facci, Laura

    2012-01-01

    The concentration of nerve growth factor (NGF) is elevated in a number of inflammatory and autoimmune states in conjunction with increased accumulation of mast cells. Mast cells, which are of hematopoietic lineage, and NGF appear to be involved in neuroimmune interactions and tissue inflammation. Mast cells themselves are capable of producing and responding to NGF. Here we describe a protocol for the isolation and culture of peritoneal-derived rat mast cells, together with a [(3)H]serotonin release assay which is useful in assessing the effects of antigens and neurotrophic factors on mast-cell activation.

  8. Degradation of C3a anaphylatoxins by rat mast cells

    SciTech Connect

    Fukuoka, Y.; Hugli, T.E.

    1986-05-01

    Incubation of /sup 125/I-human C3a with rat peritoneal mast cells (RMC) causes extensive degradation of the ligand. Both cell-bound and free /sup 125/I-C3a (hu) was degraded by RMC, even at 0/sup 0/C, based on SDS-PAGE analysis. The authors examined several protease inhibitors for their ability to prevent degradation of /sup 125/I-C3a (hu). Degradation of /sup 125/I-C3a (hu) by RMC was not inhibited by leupeptin, antipain, elastatinal, pepstatin, ..cap alpha../sub 1/-antitrypsin or EDTA. TPCK and TLCK were only partially effective. PMSF, chymostatin and SBTI were most effective in preventing /sup 125/I-C3a (hu) degradation. These latter compounds are effective inhibitors of the chymotrypsin-like enzyme chymase extracted from RMC, as is TPCK, based on hydrolysis of the substrate BTEE. Degradation of cell-bound ligand is totally prevented only by PMSF (or DFP). Therefore, /sup 125/I-C3a (hu) bound to the RMC appears to be degraded predominantly by chymase; however the cell-bound ligand is attacked by other surface proteases. Degradation of rat C3a by RMC was examined. After incubation with RMC, cell-bound and free /sup 125/I-C3a (rat) showed no evidence of degradation with or without inhibitors present. From these results, the authors conclude that chymase may not play a significant role in regulating anaphylatoxin activity. Furthermore, the authors propose that rat C3a is a preferred ligand for identifying receptors on mast cells because of its resistance to proteolysis.

  9. Thyroiditis in T cell-depleted rats: suppression of the autoallergic response by reconstitution with normal lymphoid cells.

    PubMed

    Penhale, W J; Irvine, W J; Inglis, J R; Farmer, A

    1976-07-01

    Qualititive, quantitative and functional differences were found in lymphoid cells of female thymectomized and irradiated (Tx-X) PVG/c strain rats as compared to normal females of the same strain. Tx-X rats were lymphopenic and had reduced numbers of cells within spleen and cervical lymph nodes, depressed transformation responses of peripheral blood lymphocytes to PHA and lower percentage killing of their spleen cells by anti-T-cell serum and complement. There was an increased percentage of immunoglobulin-bearing cells in the lymph nodes. Reconstitution of Tx-X rats by the intravenous route using syngeneic lymph node cells, spleen cells or thymocytes abrogated the autoimmune responses to thyroid components generally observed in this state. Lymph node and spleen cells, but not thymocytes, also prevented thyroid changes when given intraperitoneally. In contrast, bone marrow cells appeared to give enhanced responses. Quntitative studies showed that the relative proportions of the suppressor or autoregulatory cells in various lymphoid tissues were lymph node greater than spleen greater than thymus. Complete abrogation of the autoimmune responses was possible only when cells were administered within a short time of final dose of irradiation and moderate thyroid change was again seen if transfer was delayed for 14 days post-irradiation. At 28 days reconstitution had no influence on the development of the autoimmune responses. Preliminary characterization studies using an anti-T-cell serum and fractionation of lymph node cells on a linear Ficoll gradient suggested that autoregulatory cell is a large T cell.

  10. Thyroiditis in T cell-depleted rats: suppression of the autoallergic response by reconstitution with normal lymphoid cells.

    PubMed Central

    Penhale, W J; Irvine, W J; Inglis, J R; Farmer, A

    1976-01-01

    Qualititive, quantitative and functional differences were found in lymphoid cells of female thymectomized and irradiated (Tx-X) PVG/c strain rats as compared to normal females of the same strain. Tx-X rats were lymphopenic and had reduced numbers of cells within spleen and cervical lymph nodes, depressed transformation responses of peripheral blood lymphocytes to PHA and lower percentage killing of their spleen cells by anti-T-cell serum and complement. There was an increased percentage of immunoglobulin-bearing cells in the lymph nodes. Reconstitution of Tx-X rats by the intravenous route using syngeneic lymph node cells, spleen cells or thymocytes abrogated the autoimmune responses to thyroid components generally observed in this state. Lymph node and spleen cells, but not thymocytes, also prevented thyroid changes when given intraperitoneally. In contrast, bone marrow cells appeared to give enhanced responses. Quntitative studies showed that the relative proportions of the suppressor or autoregulatory cells in various lymphoid tissues were lymph node greater than spleen greater than thymus. Complete abrogation of the autoimmune responses was possible only when cells were administered within a short time of final dose of irradiation and moderate thyroid change was again seen if transfer was delayed for 14 days post-irradiation. At 28 days reconstitution had no influence on the development of the autoimmune responses. Preliminary characterization studies using an anti-T-cell serum and fractionation of lymph node cells on a linear Ficoll gradient suggested that autoregulatory cell is a large T cell. Images Fig. 2 PMID:791546

  11. No attenuation of ischemic and reperfusion injury in Kupffer cell-depleted, cold-preserved rat livers.

    PubMed

    Reinders, M E; van Wagensveld, B A; van Gulik, T M; Corssmit, N P; Frederiks, W M; Chamuleau, R A; van Rooijen, N; Obertop, H

    1997-02-15

    Activated Kupffer cells (KC) have been implicated in the damage sustained by preserved liver grafts during ischemia and reperfusion. The aim of this study was to compare ischemia/reperfusion injury in preserved, KC-depleted rat livers and preserved control livers, with special regard to sinusoidal endothelial cell (SEC) injury. Wistar rats were injected with liposome-encapsulated dichloromethylene diphosphonate, 48 hr before hepatectomy, to eliminate KC, or were withheld this pretreatment (controls). Livers were flushed with cold University of Wisconsin solution and after 0, 8, 16, or 24 hr of storage at 4 degrees C, were reperfused in a recirculation system with 200 ml of oxygenated Krebs-Henseleit solution at 37 degrees C for 90 min. Damage to SEC was measured by the uptake of hyaluronic acid (HA) from the perfusate and release of purine nucleoside phosphorylase (PNP). Perfusate samples were, furthermore, analyzed for aspartate aminotransferase (AST) and tumor necrosis factor-alpha. Carbon particles were infused in the perfusate to determine the phagocytotic capacity of KC. Biopsies were taken for histological examination and sections were stained with ED2 monoclonal antibodies to confirm the absence of KC. After 90 min of reperfusion, immediately after cold flush (t0), the uptake of HA was 72.2+/-2.3% and 69.3+/-1.3% in KC-depleted livers and in control livers, respectively (n.s.). After 8 hr of storage, HA uptake was 21.6+/-4.5% and 34.6+/-8.0%, respectively (n.s.). After 16 and 24 hr of storage and reperfusion, no uptake of HA was found in either KC-depleted or control livers, indicating abolished SEC function. PNP activities in the perfusate were higher in control livers (after 8 and 24 hr of storage), presumably due to release from damaged KC. No difference was found in AST and no tumor necrosis factor-alpha was measured in the perfusates of normal and KC-depleted livers. Electron microscopic studies showed that after 8 and 24 hr of storage and reperfusion

  12. The effects of nonidet P40 on the function of rat peritoneal mast cells in vitro.

    PubMed

    Batchelor, K W; Stanworth, D R

    1981-01-01

    1 Treatment of purified rat peritoneal mast cells at 37 degrees C with concentrations of the non-ionic detergent nonidet P40 (NP40) up to 0.005% (v/v) failed to reduce their viability. 2 There was a marked reduction in the histamine releasing capacity of NP40-treated mast cells upon challenge with a variety of selective (adrenocorticotrophic hormone 1-24 (Synacthen), rabbit anti-rat IgE antiserum, adenosine triphosphate (ATP) and the calcium ionophore, A 23187) and non-selective (rabbit anti-rat mast cell antiserum plus complement) histamine liberators. 3 Nonidet P40 (0.005%) was found to reduce the activity of a mast cell membrane 'ecto-enzyme', calcium-activated ATPase, by about 45% when presented at the time of its assay.

  13. Abolishment of TNBS-induced visceral hypersensitivity in mast cell deficient rats.

    PubMed

    Ohashi, Katsuyo; Sato, Yasushi; Kawai, Mitsuhisa; Kurebayashi, Yoichi

    2008-02-13

    Mucosal mast cells are implicated in visceral hypersensitivity associated with irritable bowel syndrome (IBS). In this study, we investigated the role of mast cells in the development of visceral hypersensitivity by using mast cell deficient (Ws/Ws) rats and their control (W+/W+). In W+/W+ rats, an injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS) into the proximal colon produced a significant decrease in pain threshold of the distal colon. Severe mucosal necrosis and inflammatory cell infiltration with concomitant increase in tissue myeloperoxidase activity were observed in the proximal colon that was directly insulted by TNBS, whereas neither necrosis nor increased myeloperoxidase activity occurred in the distal colon, indicating that TNBS-induced hypersensitivity is not caused by the local tissue damage or inflammation in the region of the gut where distention stimuli were applied. On the other hand, TNBS failed to elicit visceral hypersensitivity in Ws/Ws rats. This finding indicates that mast cells are essential for development of TNBS-induced visceral hypersensitivity in rats. Since the severity of TNBS-induced proximal colon injury and MPO activity was not affected by mast cell deficiency, it is unlikely that abolishment of visceral hypersensitivity in mast cell deficient rats was a result of altered development of the primary injury in the proximal colon. There was no difference between sham-operated Ws/Ws and W+/W+ rats in colonic pain threshold to distention stimuli, indicating that mast cells play no modulatory roles in normal colonic nociception. The present results support the view that mucosal mast cells play key roles in the pathogenesis of IBS.

  14. Activation of rat intestinal mucosal mast cells by fat absorption.

    PubMed

    Ji, Yong; Sakata, Yasuhisa; Yang, Qing; Li, Xiaoming; Xu, Min; Yoder, Stephanie; Langhans, Wolfgang; Tso, Patrick

    2012-06-01

    Previous studies have linked certain types of gut mucosal immune cells with fat intake. We determined whether fat absorption activates intestinal mucosal mast cells (MMC), a key component of the gut mucosal immune system. Conscious intestinal lymph fistula rats were used. The mesenteric lymph ducts were cannulated, and the intraduodenal (i.d.) tubes were installed for the infusion of Liposyn II 20% (an intralipid emulsion). Lymphatic concentrations of histamine, rat MMC protease II (RMCPII), a specific marker of rat intestinal MMC degranulation, and prostaglandin D(2) (PGD(2)) were measured by ELISA. Intestinal MMC degranulation was visualized by immunofluorescent microscopy of jejunum sections taken at 1 h after Liposyn II gavage. Intraduodenal bolus infusion of Liposyn II 20% (4.4 kcal/3 ml) induced approximately a onefold increase in lymphatic histamine and PGD(2), ∼20-fold increase in lymphatic RMCPII, but only onefold increase in peripheral serum RMCPII concentrations. Release of RMCPII into lymph increased dose dependently with the amount of lipid fed. In addition, i.d. infusion of long-chain triacylglycerol trilinolein (C18:2 n-6, the major composite in Liposyn II) significantly increased the lymphatic RMCPII concentration, whereas medium-chain triacylglycerol tricaprylin (C8:0) did not alter lymph RMCPII secretion. Immunohistochemistry image revealed the degranulation of MMC into lamina propria after lipid feeding. These novel findings indicate that intestinal MMC are activated and degranulate to release MMC mediators to the circulation during fat absorption. This action of fatty acid is dose and chain length dependent.

  15. Mast Cells Mediate Hyperoxia-Induced Airway Hyper-reactivity in Newborn Rats

    PubMed Central

    Schultz, Eric D.; Potts, Erin N.; Mason, Stanley N.; Foster, W. Michael; Auten, Richard L.

    2011-01-01

    Premature infants are at increased risk of developing airway hyper-reactivity following oxidative stress and inflammation. Mast cells contribute to airway hyper-reactivity partly by mediator release, so we sought to determine if blocking mast cell degranulation or recruitment prevents hyperoxia-induced airway hyper-reactivity, mast cell accumulation, and airway smooth muscle changes. Rats were exposed at birth to air or 60% O2 for 14 days, inducing significantly increased airway hyper-reactivity (AHR) in the latter group, induced by nebulized methacholine challenge, measured by forced oscillometry. Daily treatment (postnatal days 1-14) with intraperitoneal cromolyn prevented hyperoxia-induced AHR, as did treatment with imatinib on postnatal days 5-14, compared with vehicle treated controls. Cromolyn prevented mast cell degranulation in the trachea but not hilar airways, and blocked mast cell accumulation in the hilar airways. Imatinib treatment completely blocked mast cell accumulation in tracheal/hilar airway tissues. Hyperoxia-induced AHR in neonatal rats is mediated, at least in part, via the mast cell. PMID:20386143

  16. The Lectin ArtinM Induces Recruitment of Rat Mast Cells from the Bone Marrow to the Peritoneal Cavity

    PubMed Central

    de Almeida Buranello, Patricia Andressa; Moulin, Maria Raquel Isnard; Souza, Devandir Antonio; Jamur, Maria Célia; Roque-Barreira, Maria Cristina; Oliver, Constance

    2010-01-01

    Background The D-mannose binding lectin ArtinM is known to recruit neutrophils, to degranulate mast cells and may have potential therapeutic applications. However, the effect of ArtinM on mast cell recruitment has not been investigated. Methodology Male Wistar rats were injected i.p. with ArtinM or ConA (control). The ability of the lectin to degranulate peritoneal and mesenteric mast cells was examined. Recruitment of mast cells to the peritoneal cavity and mesentery after ArtinM injection was examined with or without depletion of peritoneal mast cells by distilled water. Results ArtinM degranulated both peritoneal and mesentery mast cells in vitro. Three days after i.p. injection of the lectin there were reduced numbers of mast cells in the peritoneal lavage, while at 7 days post injection of ArtinM, the number of peritoneal mast cells was close to control values. Since immature mast cells are recruited from the bone marrow, the effect of the lectin on bone marrow mast cells was examined. Injection of ArtinM resulted in an increased number of mast cells in the bone marrow. To determine if degranulation of mast cells in the peritoneal cavity was required for the increase in bone marrow mast cells, the peritoneal cavity was depleted of mast cells with ultrapure water. Exposure to ArtinM increased the number of mast cells in the bone marrow of rats depleted of peritoneal mast cells. Conclusions The ArtinM induced recruitment of mast cells from the bone marrow to the peritoneal cavity may partially explain the therapeutic actions of ArtinM. PMID:20339538

  17. Mast cells respond to urticating extract from lepidoptera larva Morpheis ehrenbergii in the rat.

    PubMed

    Galicia-Curiel, María Fernanda; Quintanar, J Luis; Jiménez, Mariela; Salinas, Eva

    2014-01-01

    Mast cells and histamine participate in toxic effects of hairs from some caterpillars. This study reports that a crude extract of Morpheis ehrenbergii caterpillar hairs induces in vitro mast cells activation, triggers the release of histamine and causes a rapid urticarial reaction in the rat skin. Heating of the extract abolishes the inflammatory reaction. These results suggest that the use of antihistamines may improve the adverse skin reactions caused by the Mexican caterpillar M. ehrenbergii.

  18. Colonic mast cell infiltration in rats with TNBS-induced visceral hypersensitivity.

    PubMed

    Ohashi, Katsuyo; Sato, Yasushi; Iwata, Hiroshi; Kawai, Mitsuhisa; Kurebayashi, Yoichi

    2007-12-01

    Colonic mucosal mast cells are implicated in the pathogenesis of visceral hypersensitivity associated with irritable bowel syndromes. This study was designed to investigate the roles of mucosal mast cells in development of an experimental visceral hypersensitivity induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) in rats. TNBS, when injected into the proximal colon through laparotomy, produced a significant decrease in pain threshold of the distal colon to mechanical distention, indicating a visceral hypersensitivity. In the proximal colon that was directly insulted by TNBS, mucosal necrosis and extensive inflammatory cell infiltration were observed with concomitant increase in tissue myeloperoxide (MPO) activity. In the distal colon where distention stimuli were applied, the number of mucosal mast cells significantly increased following TNBS treatment, although neither mucosal injury nor increase in tissue MPO activity was observed. In an organ culture, spontaneous release of a mucosal mast cell-specific protease (RMCP-2) from the distal colon tissue of TNBS-treated rats was significantly larger than that of sham animals. Furthermore, TNBS-induced visceral hypersensitivity was significantly suppressed by subcutaneous pretreatment with a mast cell stabilizer doxantrazole in a dose-dependent manner. These findings suggest that prominent colonic mast cell infiltration associated with an enhanced spontaneous mediator release is responsible, at least partly, for development of visceral hypersensitivity induced by TNBS in rats.

  19. Mechanism of low-level laser therapy (LLLT) effects on rat mast cells

    NASA Astrophysics Data System (ADS)

    Popov, Gennady K.; Solovyova, Ludmila I.; Kosel, Arnold I.

    2000-11-01

    The low power laser radiation is widely applied for treatment of various diseases. In our research we investigated the influence of low power laser radiation on the mast cells degranulation process. The object of the research were the mesentery mast cells of the rat thin intestine. A loop of thin intestine was irradiated by the therapeutic diode laser device Uley - 2K (lambda - 890 nm, pulse). The process of mast cells degranulation served as a criterion for their functional activity estimation. The estimation was fulfilled with the help of light microscope (toluidine blue staining, pH02,0; degranulating mast cells counting on 100 cells; immersion technique; X 980). To study the dependence of degranulation process of mast cells irradiated with lasre from intracellular calcium (Ca2+) concentration we applied 0,000015 M solution of verapamil, which was applied to the mesentery for 2 minutes. Laser radiation (890 nm) stimulates mesentery mast cells degranulation. This effect is dose-dependent. Maximal degranulation was registered after laser irradiation wiht power 25 mW, exposure time 15-30 s (energy density 7.5 x 103 J/m2 to 6 x 104 j/m2). Further increasing of exposure time caused the effect decreasing. The results of our experiments with verpamil let us suppose light interaction with the voltage-dependent subunit of calcium channel, changing intracellular Ca2+ and leading to stimulatory effects.

  20. Intestinal mucosal mast cells in normal and nematode-infected rat intestines are in intimate contact with peptidergic nerves.

    PubMed Central

    Stead, R H; Tomioka, M; Quinonez, G; Simon, G T; Felten, S Y; Bienenstock, J

    1987-01-01

    Inflammatory or allergic conditions, as well as situations where healing and repair processes occur, are characterized by the presence of increased numbers of mast cells. Previous work on the effect of neuropeptides on mast cell mediator release showed that only substance P caused such release from intestinal mucosal mast cells [Shanahan, F., Denburg, J. A., Fox, J., Bienenstock, J. & Befus, A. D. (1985) J. Immunol. 135, 1331-1337]. Accordingly, we investigated the microanatomical relationship between mast cells and enteric nerves in normal rat intestine and parasite-infected rat intestine, in which mucosal mast cell hyperplasia occurs. Combined immunohistochemistry for neuron-specific enolase and staining with alcian blue at pH 0.5 was employed on paraffin-embedded sections of normal and Nippostrongylus brasiliensis-infected rat jejunum. Sixty-seven percent of intestinal mucosal mast cells were touching subepithelial nerves, and an additional 20% were within 2 micron of nerves. Assessment of the proportion of the lamina propria occupied by mast cells (12.5%), the average mast cell area (121 +/- 28 microns 2), and the density of enteric nerves (one per 788 +/- 151 microns 2) suggested that the association was 5 times greater than would be expected by chance alone (P less than 0.0001). In consecutive sections, the nerves in contact with mast cells were also shown to contain substance P and/or calcitonin-gene-related peptide. Electron microscopy confirmed this association: 8% of the mast cells in infected rats exhibited membrane-membrane contact with unmyelinated axons containing 70- to 170-nm dense-core vesicles, and an additional 31% were situated less than 250 nm from nerves. Other mast cells appeared to embrace nerve bundles through the projection of lamellopodia. These data provide systematic quantitative evidence that a structural foundation for communication between the immune and nervous systems exists in the rat gastrointestinal tract. Images PMID:2437589

  1. Ghrelin and obestatin promote the allergic action in rat peritoneal mast cells as basic secretagogues.

    PubMed

    Hirayama, Tatsuya; Kawabe, Tsutomu; Matsushima, Miyoko; Nishimura, Yuko; Kobe, Yuko; Ota, Yui; Baba, Kenji; Takagi, Kenzo

    2010-11-01

    Ghrelin is an endogenous ligand of the type 1a growth hormone secretagogue receptor (GHSR1a) that regulates energy balance. Ghrelin and obestatin, derived from the post-translational processing of preproghrelin, are involved in a diverse range of biological activities, yet their effect on the immune system is not fully understood. In the present study, we investigated the roles of ghrelin and obestatin on mast cell degranulation and found that both ghrelin and obestatin induce the release of histamine from rat peritoneal mast cells. This induced histamine release was inhibited by the pertussis toxin, an inhibitor of Gα(i) protein, and extracellular Ca(2+). Rat peritoneal mast cells and rat basophilic leukemia (RBL-2H3) cells did not express the ghrelin receptor GHSR1a, suggesting that histamine release induced by ghrelin occurs via a receptor-independent mechanism. We report here that ghrelin and obestatin, belonging to the family of basic secretagogues, stimulate mast cells independent of a receptor, and this may play a crucial role at the site of allergy or inflammation.

  2. Agarwood Inhibits Histamine Release from Rat Mast Cells and Reduces Scratching Behavior in Mice

    PubMed Central

    Inoue, Eiji; Shimizu, Yasuharu; Masui, Ryo; Tsubonoya, Tomoe; Hayakawa, Tomomi; Sudoh, Keiichi

    2016-01-01

    Objectives: This study was conducted to clarify the effects of agarwood on histamine release from mast cells in rats and on the scratching behaviors in mice. Methods: Histamine release from rat mast cells induced by compound 48/80 or concanavalin A (Con A) and compound 48/80-induced scratching behavior in mice were examined to investigate the effects of agarwood. The hyaluronidase activity and the 3’,5’-cyclic adenosine monophosphate (cAMP) levels in mast cells were examined to investigate the mechanisms for the inhibition of histamine release. The correlation between the inhibitory effects of agarwood on histamine release and the content of its typical ingredients, a 2-(2-phenylethyl)chromone derivatives, was analyzed using thin-layer chromatography. Results: Agarwood showed an inhibitory effect on mast-cell histamine release induced by compound 48/80 or Con A without any effect on hyaluronidase activity; this effect involves an increase in the cAMP levels in mast cells. Oral administration of agarwood showed an inhibitory effect on compound 48/80-induced scratching behavior in mice. The inhibitory effects of agarwood on histamine release were quite different, depending on the area where the agarwood was produced, its quality, and its market price. No correlation was found between the inhibitory effects of agarwood on histamine release and the typical ingredients of agarwood, which are 2-(2-phenylethyl)chromone derivatives. Conclusion: These results show that agarwood inhibits histamine release from mast cells partially through an increase in the cAMP levels in cells. We suggest that some active ingredients of agarwood must be effective on oral intake and that agarwood can be used to treat patients with a number of conditions, including urticaria, atopic dermatitis, and bronchial asthma, in which an increase in histamine release occurs. Differences in the pharmacological effects of this crude drug among markets may provide important information for the quality

  3. Effects of human hair and nail proteins and their films on rat mast cells.

    PubMed

    Fujii, Toshihiro; Murai, Shinya; Ohkawa, Kousaku; Hirai, Toshihiro

    2008-06-01

    Human hair and nail are valuable materials for producing individual corresponding biocompatible materials. A rapid and convenient protein extraction method (Shindai method) and novel procedures for preparing their protein films from their extracts have been developed using human hair and nail. The effects of the human hair and nail proteins and their films on histamine release from rat peritoneal mast cells were investigated. Both protein solutions and their films, mainly consisting of keratins and matrix proteins, did not induce histamine release from the mast cells. Scanning electron microscopy (SEM) also showed that the mast cells were only slightly affected by adding the human hair and nail proteins or by incubating on their protein films. The IgE-dependent histamine release was inhibited by the hair and nail proteins and their films. Incubation of the mast cells with the hair and nail proteins prior to the addition of the IgE serum resulted in a high inhibition (50%) of the histamine release, while the inhibition was approximately 10% when the protein solutions were mixed with the mast cells after incubation with the IgE serum. These results suggest that the human hair and nail proteins and their films will be useful materials for antiallergic actions.

  4. Induction of mast cell proliferation, maturation, and heparin synthesis by the rat c-kit ligand, stem cell factor

    SciTech Connect

    Tsai, M.; Takeishi, Takashi; Geissler, E.N. ); Thompson, H.; Metcalfe, D.D. ); Langley, K.E.; Zsebo, K.M.; Galli, S.J. )

    1991-07-15

    The authors investigated the effects of a newly recognized multifunctional growth factor, the c-kit ligand stem cell factor (SCF), on mouse mast cell proliferation and phenotype. Recombinant rat SCF{sup 164} (rrSCF{sup 164}) induced the development of large numbers of dermal mast cells in normal mice in vivo. Many of these mast cells had features of connective tissue-type mast cells (CTMC), in that they were reactive both with the heparin-binding fluorescent dye berberine sulfate and with safranin. In vitro, rrSCF{sup 164} induced the proliferation of cloned interleukin 3 (IL-3)-dependent mouse mast cells and primary populations of IL-3-dependent, bone marrow-derived cultured mast cells (BMCMC), which represent immature mast cells, and purified peritoneal mast cells, which represent a type of mature CTMC> BMCMC maintained in rrSCF{sup 164} not only proliferated but also matured. These findings identify SCF as a single cytokine that can induce immature, IL-3-dependent mast cells to mature and to acquire multiple characteristics of CTMC. These findings also directly demonstrate that SCF can regulate the development of a cellular lineage expressing c-kit through effects on both proliferation and maturation.

  5. Effects of relaxin on mast cells. In vitro and in vivo studies in rats and guinea pigs.

    PubMed Central

    Masini, E; Bani, D; Bigazzi, M; Mannaioni, P F; Bani-Sacchi, T

    1994-01-01

    The results of the current study demonstrate that relaxin inhibits histamine release by mast cells. This effect is related to the peptide concentrations, and could be observed in both isolated rat serosal mast cells stimulated with compound 48/80 or calcium ionophore A 23187, and in serosal mast cells isolated from sensitized guinea pigs and challenged with the antigen. The morphological findings agree with the functional data, revealing that relaxin attenuates calcium ionophore-induced granule exocytosis by isolated rat serosal mast cells. Similar effects of relaxin have also been recognized in vivo by light microscopic and densitometric analysis of the mesenteric mast cells of rats which received the hormone intraperitoneally 20 min before local treatment of the mesentery with calcium ionophore. Moreover, evidence is provided that relaxin stimulates endogenous production of nitric oxide and attenuates the rise of intracellular Ca2+ concentration induced by calcium ionophore. The experiments with drugs capable of influencing nitric oxide production also provide indirect evidence that the inhibiting effect of relaxin on mast cell histamine release is related to an increased generation of nitric oxide. It is suggested that relaxin may have a physiological role in modulating mast cell function through the L-arginine-nitric oxide pathway. Images PMID:7525651

  6. Alpha-lipoic acid and N-acetylcysteine protects intensive swimming exercise-mediated germ-cell depletion, pro-oxidant generation, and alteration of steroidogenesis in rat testis.

    PubMed

    Jana, Kuladip; Dutta, Ananya; Chakraborty, Pratip; Manna, Indranil; Firdaus, Syed Benazir; Bandyopadhyay, Debasish; Chattopadhyay, Ratna; Chakravarty, Baidyanath

    2014-09-01

    Prolonged and strenuous exercise has been proposed as a possible source of male-factor infertility. Forced intensive swimming has also been identified as one source of a dysfunctional male reproduction system. The present study evaluated the possible protective role of α-lipoic acid and N-acetylcysteine (NAC) on intensive swimming-induced germ-cell depletion in adult male rats. Forced exhaustive swimming of 1 hr/day, 6 days/week for 8 consecutive weeks resulted in a significant (P < 0.05) reduction in epididymal sperm; testicular androgenic enzyme activities; and plasma and intra-testicular testosterone; and produced different types of germ cells in the seminiferous epithelium cycle. Conversely, plasma corticosterone levels and sperm-head abnormalities increased. Western-blot analysis showed a considerable decrease in testicular StAR protein expression whereas reverse-transcriptase PCR analysis showed no significant change in cytochrome P450scc (Cyp11a1) gene expression. Significant (P < 0.05) elevation in testicular reactive oxygen species (ROS), lipid peroxidation, protein carbonyl content versus reduction in glucose-6-phosphate dehydrogenase, glutathione peroxidase, glutathione S-transferase, and caspase-3 activities along with a depletion in the glutathione pool, mitochondrial membrane potential (▵ψm ), and intracellular ATP generation. A considerable level of DNA damage in testicular spermatogenic cells were also noted following forced extensive swimming. Alpha-lipoic acid and NAC supplementation prevented the swimming-induced testicular spermatogenic and steroidogenic disorders by lowering ROS generation. We therefore conclude that intensive forced swimming causes germ-cell depletion through the generation of ROS and depletion of steroidogenesis in the testis, which can be protected by the co-administration of α-lipoic acid and NAC.

  7. Malignant mast cell tumor of the thymus in an Royal College of Surgeons (RCS) rat.

    PubMed

    Terayama, Yui; Matsuura, Tetsuro; Ozaki, Kiyokazu

    2017-01-01

    A 152-week-old male Royal College of Surgeons (RCS) rat kept as a non-treated animal in a long-term animal study presented with a soft mass in the anterior mediastinum, which adhered to the pleura of the lung. Histopathologically, the mass mainly consisted of round to short spindle-shaped tumor cells that had infiltrated through the hyperplastic thymic tissue. The tumor cells were arranged in loose to dense sheets. Nuclei were moderate in size and round to spindle-shaped, with small nucleoli. Almost all tumor cells exhibited abundant eosinophilic cytoplasm, including eosinophilic granules of a range of sizes. The granules of tumor cells exhibited metachromasia with toluidine blue stain and were positive for c-kit and mast cell protease II. These findings indicate that the tumor described here represents a rare case of spontaneous malignant mast cell tumor with thymic epithelial hyperplasia.

  8. Study of the activation mechanism of adriamycin on rat mast cells.

    PubMed

    Estévez, M D; Vieytes, M R; Botana, L M

    1994-10-01

    Adriamycin (ADR) induces nonimmunological and noncytotoxic histamine release from peritoneal and pleural rat mast cells. This secretion is unaffected by the pretreatment with pertussis toxin, cholera toxin and benzalkonium chloride. Histamine release induced by compound 48/80, was markedly inhibited by pertussis toxin, cholera toxin, benzalkonium chloride and neuraminidase. The ADR dose-response curve is significantly shifted to the right when cells were preincubated with the unspecific phosphodiesterase inhibitor IBMX. The activation of protein kinase C (PKC) with the phorbol esther TPA increases the response to ADR, while PKC inhibition with trifluoperazine decreases histamine release. The pretreatment of mast cells with okadaic acid did not modify the response to ADR. These results suggest that ADR elicits histamine release with a mechanism notably different from compound 48/80.

  9. Mast Cell Inhibition Attenuates Myocardial Damage, Adverse Remodeling and Dysfunction during Fulminant Myocarditis in Rat

    PubMed Central

    Mina, Yair; Rinkevich-Shop, Shunit; Konen, Eli; Goitein, Orly; Kushnir, Tammar; Epstein, Frederick H.; Feinberg, Micha S.; Leor, Jonathan; Landa-Rouben, Natalie

    2013-01-01

    Background Myocarditis is a life-threatening heart disease characterized by myocardial inflammation, necrosis and chronic fibrosis. While mast cell inhibition has been suggested to prevents fibrosis in rat myocarditis, little is known about its effectiveness in attenuating cardiac remodeling and dysfunction in myocarditis. Thus, we sought to test the hypothesis that mast cell inhibition will attenuate the inflammatory reaction and associated left ventricular (LV) remodeling and dysfunction after fulminant autoimmune myocarditis. Methods and Results To induce experimental autoimmune myocarditis, we immunized 30 rats with porcine cardiac myosin twice at a 7-day interval. On day 8 animals were randomized into treatment either with an intraperitoneal (IP) injection of 25mg/kg of cromolyn sodium (n=13), or an equivalent volume (~0.5ml IP) of normal saline (n=11). All animals were scanned by serial echocardiography studies before treatment (baseline echocardiogram) and after 20 days of cromolyn sodium (28 days after immunization). Furthermore, serial cardiac magnetic resonance was performed in a subgroup of 12 animals. After 20 days of treatment (28 days from first immunization), hearts were harvested for histopathological analysis. By echocardiography, cromolyn sodium prevented LV dilatation and attenuated LV dysfunction, compared with controls. Postmortem analysis of hearts showed that cromolyn sodium reduced myocardial fibrosis, as well as the number and size of cardiac mast cells in the inflamed myocardium, compared with controls. Conclusions Our study suggests that mast cell inhibition with cromolyn sodium attenuates adverse LV remodeling and dysfunction in myocarditis. This mechanism-based therapy is clinically relevant and could improve the outcome of patients at risk for inflammatory cardiomyopathy and heart failure. PMID:23172937

  10. The Effect of Tong-Xie-Yao-Fang on Intestinal Mucosal Mast Cells in Postinfectious Irritable Bowel Syndrome Rats

    PubMed Central

    Wang, Xiaoge; Kang, Nan; Chen, Ting; Ji, Haijie; Yin, Xiaolan; Tian, Yaxin; Zheng, Rui; Duan, Yuanzhi

    2017-01-01

    Objective. To investigate the effects of Tong-Xie-Yao-Fang (TXYF) on intestinal mucosal mast cells in rats with postinfectious irritable bowel syndrome (PI-IBS). Design. PI-IBS rat models were established using a multistimulation paradigm. Then, rats were treated with TXYF intragastrically at doses of 2.5, 5.0, and 10.0 g·kg−1·d−1 for 14 days, respectively. Intestinal sensitivity was assessed based on abdominal withdrawal reflex (AWR) scores and fecal water content (FWC). Mast cell counts and the immunofluorescence of tryptase and c-Fos in intestinal mucosa were measured; and serum IL-1β, TNF-α, and histamine levels were determined. Results. AWR reactivity and FWC which were significantly increased could be observed in PI-IBS rats. Remarkably increased mast cell activation ratio in intestinal mucosa, together with increased serum TNF-α and histamine levels, could also be seen in PI-IBS rats; furthermore, PI-IBS-induced changes in mast cell activation and level of serum TNF-α and histamine could be reversed by TXYF treatment. Meanwhile, tryptase and c-Fos expression were also downregulated. Conclusion. TXYF improves PI-IBS symptoms by alleviating behavioral hyperalgesia and antidiarrhea, the underlying mechanism of which involves the inhibitory effects of TXYF on activating mucosal mast cells, downregulating tryptase and c-Fos expression, and reducing serum TNF-α and histamine levels. PMID:28331524

  11. Local cutaneous nerve terminal and mast cell responses to manual acupuncture in acupoint LI4 area of the rats.

    PubMed

    Wu, Mei-Ling; Xu, Dong-Sheng; Bai, Wan-Zhu; Cui, Jing-Jing; Shu, Hong-Ming; He, Wei; Wang, Xiao-Yu; Shi, Hong; Su, Yang-Shuai; Hu, Ling; Zhu, Bing; Jing, Xiang-Hong

    2015-10-01

    Previous studies have shown that the effects of manual acupuncture (MA) are contributed by collagen fibers and mast cells in local acupoints, at which acupuncture stimulation causes various afferent fiber groups to be excited. However what happens in local nerve fibers and mast cells after MA remains unclear. The aim of this study was to examine the response of cutaneous nerve fibers and mast cells to MA stimulation in acupoint Hegu (LI4). The contralateral LI4 of the same rat was used as a non-stimulated control. Immnohistochemistry analysis were carried out to observe the expression of histamine (HA), serotonin (5-HT) and nociceptive neuropeptides, calcitonin gene-related peptide (CGRP) and substance P (SP), in the LI4 area. Mast cells were labeled with anti-mast cell tryptase antibody and simultaneously with HA or 5-HT primary antibodies to observe their co-expression. Our results showed that SP and CGRP were expressed more highly on the cutaneous nerve fibers of LI4 after MA stimulation than that of the control. Mast cells aggregated in close proximity to the blood vessels in intra-epidermis and dermis and some of them with degranulation in the lower dermis and subcutaneous tissue of LI4. Both mast cells and their granules appeared with HA (+) and 5-HT (+) expression at stimulated L14 sites, while a few intact mast cells with a little expression of 5-HT and HA were distributed in areas of non-stimulated L14. The results indicated that local cutaneous nerve terminals and mast cells responded to MA with higher expression of SP and CGRP in nerve fibers, as well as with aggregation and degranulation of mast cells with HA and 5-HT granules at acupoint LI4. These neuroactive substances may convey signals to certain pathways that contribute to the effects of acupuncture.

  12. Dual effects of protoporphyrin and long wave ultraviolet light on histamine release from rat peritoneal and cutaneous mast cells

    SciTech Connect

    Yen, A.; Gigli, I.; Barrett, K.E. )

    1990-06-01

    In this study we investigated the effects of long wave ultraviolet light (UVA) and various doses of protoporphyrin (PP) on the release of histamine from rat peritoneal and cutaneous mast cells. We also correlated these results with morphologic characteristics and viability of the cells. PP at a dose of 30 ng/ml plus UVA-induced negligible histamine release from rat peritoneal mast cells (RPMC), but was able to suppress the ability of the cells to release histamine in response to subsequent exposure to the calcium ionophore A23187, compound 48/80, or the combination of Ag and IgE. This functional change was associated with an increase in cell size, and cell lysis that gradually occurred during 24 h in culture. PP at a dose of 3 ng/ml plus UVA also significantly inhibited secretogogue-induced histamine release from rat peritoneal mast cells, but this dose was not associated with significant changes in morphology or viability. These various effects of PP plus UVA were also observed with mast cell preparations obtained by the enzymatic dispersion of rat skin. The suppression of secretogogue-induced histamine release in rat peritoneal mast cells treated with PP (3 ng/ml) and UVA could not be reversed by culturing the cells in the dark for 24 h in the absence of PP. Unlike the direct cytotoxic histamine releasing action of high doses of PP plus UVA, the suppressive effect of low PP doses could not be inhibited by catalase, but could be reduced by the absence of calcium. Our results indicate that PP plus UVA has dual effects on mast cells, apparently involving distinct mechanisms. This implies the possibility that PP and UVA at appropriate doses could be used in photochemotherapy of mast cell-mediated skin diseases.

  13. Mast cells and MMP-9 in the lamina propria during eruption of rat molars: quantitative and immunohistochemical evaluation.

    PubMed

    Cerri, Paulo Sérgio; Pereira-Júnior, Jorge Alonso; Biselli, Natalia Barrionuevo; Sasso-Cerri, Estela

    2010-08-01

    During the active tooth eruption process, structural changes in the lamina propria are necessary to provide extracellular matrix remodelling and for the establishment of the eruptive pathway. A large number of resident cells, recruited cells and proteases have been demonstrated in the eruptive process, but the participation of MMP-9 and mast cells has not yet been demonstrated. In this study, we set out to evaluate the intensity of MMP-9 immunoexpression, the frequency of mast cells and the correlation between the incidence of mast cells and bone resorption in different phases of tooth eruption. Fragments of maxilla containing first molars, obtained from 9-, 11-, 13- and 16-day-old rats, were fixed in 4% formaldehyde, decalcified and embedded in paraffin. Sagittal sections were stained with Masson's trichrome or submitted to the tartrate-resistant acid phosphatase method for quantification of osteoclasts. Sections stained by 1% toluidine blue were used for quantification of metachromatic mast cells mm(-2) of lamina propria. The expression of MMP-9 in the lamina propria was evaluated by immunohistochemistry. In the 9-day-old rats, the lamina propria contained few mast cells and occasional osteoclasts were found in the bone surface overlying the occlusal portion of the tooth germs. Otherwise, a significant increase in the number of mast cells was observed in the intra-osseous phase of tooth eruption (11-day-old rats), period in which numerous TRAP-positive osteoclasts were found in the bone surface. MMP-9 immunolabelling was detected in fibroblasts, mast cells and macrophage-like cells of the lamina propria in all ages studied. However, an enhanced immunolabelling was evident in the advanced phase of tooth eruption (16-day-old rats). During the intra-osseous phase, the parallel between the high frequency of both mast cells and osteoclasts suggests that mast cells could exert a paracrine function on the osteoclasts and then stimulate bone resorption. The

  14. Kupffer cell depletion protects against the steatosis, but not the liver damage, induced by marginal-copper, high-fructose diet in male rats

    PubMed Central

    Schuschke, Dale A.; Zhou, Zhanxiang; Zhong, Wei; Zhang, Jiayuan; Zhang, Xiang; Wang, Yuhua; McClain, Craig J.

    2015-01-01

    High-fructose feeding impairs copper status and leads to low copper availability, which is a novel mechanism in obesity-related fatty liver. Copper deficiency-associated hepatic iron overload likely plays an important role in fructose-induced liver injury. Excess iron in the liver is distributed throughout hepatocytes and Kupffer cells (KCs). The aim of this study was to examine the role of KCs in the pathogenesis of nonalcoholic fatty liver disease induced by a marginal-copper high-fructose diet (CuMF). Male weanling Sprague-Dawley rats were fed either a copper-adequate or a marginally copper-deficient diet for 4 wk. Deionized water or deionized water containing 30% fructose (wt/vol) was also given ad libitum. KCs were depleted by intravenous administration of gadolinium chloride (GdCl3) before and/or in the middle of the experimental period. Hepatic triglyceride accumulation was completely eliminated with KC depletion in CuMF consumption rats, which was associated with the normalization of elevated plasma monocyte chemoattractant protein-1 (MCP-1) and increased hepatic sterol regulatory element binding protein-1 expression. However, hepatic copper and iron content were not significantly affected by KC depletion. In addition, KC depletion reduced body weight and epididymal fat weight as well as adipocyte size. Plasma endotoxin and gut permeability were markedly increased in CuMF rats. Moreover, MCP-1 was robustly increased in the culture medium when isolated KCs from CuMF rats were treated with LPS. Our data suggest that KCs play a critical role in the development of hepatic steatosis induced by marginal-copper high-fructose diet. PMID:25813056

  15. Separate effects of irradiation and of graft-versus-host reaction on rat mucosal mast cells.

    PubMed Central

    Cummins, A G; Munro, G H; Huntley, J F; Miller, H R; Ferguson, A

    1989-01-01

    T cell mediated immune responses in the gut can produce enteropathy and malabsorption. We have investigated the relevance of mucosal mast cells (MMC) to the mechanisms of this enteropathy by using graft-versus-host reaction (GvHR) in the rat as a model of mucosal delayed type hypersensitivity. Measurements of mucosal architecture, intraepithelial lymphocytes (IEL) and MMC counts were performed in control and experimental rats, and release of rat mast cell protease II (RMCPII) into the bloodstream was used as an index of MMC activation. In unirradiated rats, jejunal MMC count was increased on day 14 of the GvHR (mean 272/mm2 v 182 in controls, p less than 0.01), as was serum RMCPII (p less than 0.01). Irradiated rats (4.5 Gy, reconstituted with isogeneic spleen cells) had low counts of IEL and crypt hyperplasia seven to 14 days after irradiation. Irradiated rats with GvHR (induced by ip injection of parental strain spleen cells) and studied on days 7, 10 and 14, had significant enteropathy with longer crypts and higher CCPR than matched irradiated animals (p less than 0.05 on day 14 when compared with irradiation alone). Intraepithelial lymphocytes counts, however, reflected only the effect of radiation. Irradiation, with or without GvHR, led to the virtual disappearance of jejunal MMC, undetectable jejunal RMCPII and very low levels of RMCPII in serum (all p less than 0.01 when compared with unirradiated controls). These experiments show that there is a modest expansion in jejunal MMC in unirradiated rats with semiallogeneic GvHR, whereas irradiation, alone or associated with GvHR, profoundly depletes MMC for at least two weeks. The enteropathy of GvHR can evolve in the virtual absence of MMC. PMID:2707634

  16. Elemental levels in mast cell granules differ in sections from normal and diabetic rats: an X-ray microanalysis study

    SciTech Connect

    Kendall, M.D.

    1988-03-01

    Mast cells around the thymus of rats stain red with alcian blue and safranin indicating that the mast cells are probably of the peritoneal (connective tissue) type. After the onset of streptozotocin induced diabetes some cells contain both red and blue granules and blue staining cells may appear. X-ray microanalysis of frozen freeze-dried sections from diabetic male CSE Wistar rats showed electron dense granules to have similar amounts of S to normal rat mast cell granules but reduced levels of Na, Mg, P, Cl and K. Two cells also had electron lucent granules with very high levels of Na, Cl, K and Ca and reduced concentrations of S. The differences in elemental composition suggest that the mast cells from diabetic rats are not immature, but are related to the condition of induced diabetes, and that granules of very different composition can occur within a single cell. X-ray microanalysis has given an insight into mast cell granule elemental content which was not possible by conventional biochemical methods.

  17. Influence of laser and LED irradiation on mast cells of cutaneous wounds of rats with iron deficiency anemia

    NASA Astrophysics Data System (ADS)

    Becher Rosa, Cristiane; Oliveira Sampaio, Susana C. P.; Monteiro, Juliana S. C.; Ferreira, Maria F. L.; Zanini, Fátima A. A.; Santos, Jean N.; Cangussú, Maria Cristina T.; Pinheiro, Antonio L. B.

    2011-03-01

    This work aimed to study histologically the effect of Laser or LED phototherapy on mast cells on cutaneous wounds of rats with iron deficiency. 18 rats were used and fed with special peleted iron-free diet. An excisional wound was created on the dorsum of each animal which were divided into: Group I - Control with anemia + no treatment; Group II - Anemia + Laser; Group III - Anemia + LED; Group IV - Healthy + no treatment; Group V - Healthy + Laser; Group VI - Healthy + LED. Irradiation was performed using a diode Laser (λ660nm, 40mW, CW, total dose of 10J/cm2, 4X2.5J/cm2) or a RED-LED ( λ700nm, 15mW, CW, total dose of 10J/cm2). Histological specimens were routinely processed, cut and stained with toluidine blue and mast cell counts performed. No significant statistic difference was found between groups as to the number of degranulated, non-degradulated or total mast cells. Greater mean values were found for degranulated mast cells in the Anemia + LED. LED irradiation on healthy specimens resulted in a smaller number of degranulated mast cells. Our results leads to conclude that there are no significant differences in the number of mast cells seven days after irradiation following Laser or LED phototherapy.

  18. Influence of salmeterol and benzalkonium chloride on G-protein-mediated exocytotic responses of rat peritoneal mast cells.

    PubMed

    Seebeck, J; Krebs, D; Ziegler, A

    2000-05-26

    The long-acting beta(2)-adrenoceptor agonist salmeterol and the invert soap benzalkonium chloride share physicochemically important structures, namely a polar head group and a long aliphatic chain. Low concentrations of benzalkonium chloride have been shown to inhibit exocytotic responses in rat peritoneal mast cells by selectively interacting with heterotrimeric G-proteins of the G(i)-type. The present study investigates whether salmeterol inhibits, independently of beta-adrenoceptors, exocytotic responses of rat peritoneal mast cells induced by the direct agonists at G-proteins mastoparan or guanosine 5'-O-(3-thiotriphosphate) (++GTP gamma S++). Exocytosis was studied by secretion assays ([3H]5-hydroxytryptamine ([3H]5-HT)-release) using intact, streptolysin O-permeabilised or metabolically inhibited (antimycin, deoxyglucose) rat peritoneal mast cells. Both amphiphilics, salmeterol, and benzalkonium chloride, dose-dependently exerted biphasic effects on mastoparan-induced [3H]5-HT release in intact mast cells. In contrast to benzalkonium chloride, the dose-response curves for secretostatic and celltoxic effects of salmeterol markedly overlapped. Similar to benzalkonium chloride, salmeterol in non-cytotoxic concentrations (1-25 microg/ml) dose-dependently inhibited exocytosis induced by mastoparan (intact cells) or ++GTP gamma S (permeabilised cells). These findings indicate a direct, adrenoceptor-independent affection of G proteins by salmeterol in mast cells.

  19. Cannabinoids reduce granuloma-associated angiogenesis in rats by controlling transcription and expression of mast cell protease-5

    PubMed Central

    De Filippis, D; Russo, A; D'Amico, A; Esposito, G; Concetta, P; Cinelli, M; Russo, G; Iuvone, T

    2008-01-01

    Background and purpose: Chronic inflammatory conditions, such as granulomas, are associated with angiogenesis. Mast cells represent the main cell type orchestrating angiogenesis, through the release of their granule content. Therefore, compounds able to modulate mast cell behaviour may be considered as a new pharmacological approach to treat angiogenesis-dependent events. Here, we tested the effect of selective cannabinoid (CB) receptor agonists in a model of angiogenesis-dependent granuloma formation induced by λ-carrageenin in rats. Experimental approach: Granulomas were induced by λ-carrageenin-soaked sponges implanted subcutaneously on the back of male Wistar rats. After 96 h, implants were removed and granuloma formation was measured (wet weight); angiogenesis was evaluated by histological analysis and by the measurement of haemoglobin content. Mast cells in the granulomas were evaluated histologically and by RT-PCR and immunoblotting analysis for mast cell-derived proteins (rat mast cell protease-5 (rMCP-5) and nerve growth factor). Selective CB1 and CB2 receptor agonists, ACEA and JWH-015 (0.001–0.1 mg mL−1), were given locally only once, at the time of implantation. Key results: The CB1 and CB2 receptor agonists decreased the weight and vascularization of granulomas after 96 h. This treatment also reduced mast cell number and activation in granulomatous tissue. Specifically, these compounds prevented the transcription and expression of rMCP-5, a protein involved in sprouting and advance of new blood vessels. Conclusion and implications: Modulation of mast cell function by cannabinoids reduced granuloma formation and associated angiogenesis. Therefore cannabinoid-related drugs may be useful in the management of granulomatous diseases accompanied by angiogenesis. PMID:18552882

  20. Combination chemotherapy with cyclophosphamide, epirubicin and 5-fluorouracil causes trabecular bone loss, bone marrow cell depletion and marrow adiposity in female rats.

    PubMed

    Fan, Chiaming; Georgiou, Kristen R; McKinnon, Ross A; Keefe, Dorothy M K; Howe, Peter R C; Xian, Cory J

    2016-05-01

    The introduction of anthracyclines to adjuvant chemotherapy has increased survival rates among breast cancer patients. Cyclophosphamide, epirubicin and 5-fluorouracil (CEF) combination therapy is now one of the preferred regimens for treating node-positive breast cancer due to better survival with less toxicity involved. Despite the increasing use of CEF, its potential in causing adverse skeletal effects remains unclear. Using a mature female rat model mimicking the clinical setting, this study examined the effects of CEF treatment on bone and bone marrow in long bones. Following six cycles of CEF treatment (weekly intravenous injections of cyclophosphamide at 10 mg/kg, epirubicin at 2.5 mg/kg and 5-flurouracil at 10 mg/kg), a significant reduction in trabecular bone volume was observed at the metaphysis, which was associated with a reduced serum level of bone formation marker alkaline phosphatase (ALP), increased trends of osteoclast density and osteoclast area at the metaphysis, as well as an increased size of osteoclasts being formed from the bone marrow cells ex vivo. Moreover, a severe reduction of bone marrow cellularity was observed following CEF treatment, which was accompanied by an increase in marrow adipose tissue volume. This increase in marrow adiposity was associated with an expansion in adipocyte size but not in marrow adipocyte density. Overall, this study indicates that six cycles of CEF chemotherapy may induce some bone loss and severe bone marrow damage. Mechanisms for CEF-induced bone/bone marrow pathologies and potential preventive strategies warrant further investigation.

  1. Cyclic GMP signaling in rat urinary bladder, prostate, and epididymis: tissue-specific changes with aging and in response to Leydig cell depletion.

    PubMed

    Müller, Dieter; Mukhopadhyay, Amal K; Davidoff, Michail S; Middendorff, Ralf

    2011-08-01

    Aging of the male reproductive system leads to changes in endocrine signaling and is frequently associated with the emergence of prostate hyperplasia and bladder dysfunctions. Recent reports highlight prostate and bladder as promising targets for therapeutic interventions with inhibitors of the cyclic GMP (cGMP)-degrading phosphodiesterase 5 (PDE5). However, the cGMP signaling system in these organs is as yet poorly characterized, and the possibility of age-related alterations has not been addressed. This study investigates key proteins of cGMP pathways in bladder, prostate, and epididymis of young (3 months) and old (23-24 months) Wistar rats. Local differences in the abundance of PDE5, soluble guanylyl cyclase (sGC) and particulate guanylyl cyclases (GC-A, GC-B), endothelial nitric oxide synthase, and cGMP-dependent protein kinase I (PRKG1 (cGKI)) revealed pronounced tissue-specific peculiarities. Although cGMP-generating enzymes were not affected by age in all organs, we recognized age-related decreases of PDE5 expression in bladder and a selective diminishment of membrane-associated PRKG1 in epididymis. In disagreement with published data, all cGMP pathway proteins including PDE5 are poorly expressed in prostate. However, prostatic PRKG1 expression increases with aging. Androgen withdrawal during temporary Leydig cell elimination induced a massive (>12-fold) upregulation of PRKG1 in prostate but not in other (penis and epididymis) androgen-dependent organs. These findings identify PRKG1 as a key androgen-sensitive signaling protein in prostate of possible importance for growth regulation. The elucidated effects may have significance for age-associated pathologies in the male lower-urinary tract.

  2. The stem of sinomenium acutum inhibits mast cell-mediated anaphylactic reactions and tumor necrosis factor-alpha production from rat peritoneal mast cells.

    PubMed

    Kim, H M; Moon, P D; Chae, H J; Kim, H R; Chung, J G; Kim, J J; Lee, E J

    2000-05-01

    The aqueous extract of Sinomenium acutum stem (SSAE) (0.1-1000 mg/kg) dose-dependently inhibited systemic anaphylactic reaction induced by compound 48/80 in mice. In particular, SSAE reduced compound 48/80-induced anaphylactic reaction with 50% at the dose of 1000 mg/kg. SSAE (100-1000 mg/kg) also significantly inhibited local anaphylactic reaction activated by anti-dinitrophenyl (DNP) IgE. When mice were pretreated with SSAE at a concentration ranging from 0.1 to 1000 mg/kg, the plasma histamine levels were reduced in a dose-dependent manner. SSAE (1-1000 microg/ml) dose-dependently inhibited histamine release from the rat peritoneal mast cells (RPMCs) activated by compound 48/80 or anti-DNP IgE. In addition, SSAE (0.1 microg/ml) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production. These results indicate that SSAE inhibits mast cell-mediated anaphylactic reactions and TNF-alpha production from mast cells.

  3. Suppressed histamine release from rat peritoneal mast cells by ultraviolet B irradiation: decreased diacylglycerol formation as a possible mechanism

    SciTech Connect

    Danno, K.; Fujii, K.; Tachibana, T.; Toda, K.; Horio, T.

    1988-06-01

    This study was designed to investigate the effect of ultraviolet B (UVB) irradiation on mast cell functions. Purified mast cells obtained from rat peritoneal cavity were irradiated with UVB and subsequently exposed to a degranulator, compound 48/80, or the calcium ionophore A-23187. The amount of histamine released from mast cells measured by the enzyme isotopic assay was significantly decreased by UVB irradiation (100-400 mJ/cm2). Within this dose range, UVB alone was not cytotoxic to the cells because it did not induce histamine release. The suppression was observed when mast cells were subjected to degranulation without intervals after UVB irradiation, and even after 5 h postirradiation. The wavelength of 300 nm from a monochromatic light source showed the maximum effect. When mast cells prelabeled with (/sup 3/H)arachidonate were irradiated and challenged by compound 48/80, label accumulation in diacylglycerol produced by the phosphatidylinositol cycle was considerably decreased by UVB irradiation. From these results, we hypothesize that, within an adequate irradiation dose, UVB irradiation suppresses histamine release from mast cells, probably by causing noncytotoxic damage to the membrane phospholipid metabolism, which is tied to the degranulation mechanisms.

  4. Fibroblasts maintain the phenotype and viability of the rat heparin-containing mast cell in vitro

    SciTech Connect

    Levi-Schaffer, F.; Austen, K.F.; Caulfield, J.P.; Hein, A.; Bloes, W.F.; Stevens, R.L.

    1985-11-01

    Rat serosal heparin-containing mast cells (HP-MC) were maintained in vitro for as long as 30 days when co-cultured with mouse skin-derived 3T3 fibroblasts. In contrast, when the mast cells were cultured alone, on fibronectin-, gelatin-, or dermal-collagen-coated dishes, on acid and heat-killed fibroblasts in the presence or absence of 24 hr fibroblast-conditioned medium, or on a monolayer of mouse serosal macrophages, they failed to adhere to the dishes, released significant amounts of their histamine and lactate dehydrogenase, and stained with trypan blue, indicating a loss of viability. The rat serosal HP-MC cultured with the 3T3 fibroblasts became so adherent to the fibroblasts that the two cell types could be separated from one another only by trypsinization. The cultured HP-MC stained with both alcian blue and safranin and continued to synthesize proteoglycan at a rate comparable to that of freshly isolated cells. The /sup 35/S-labeled proteoglycan synthesized by these cultured cells, like that produced by freshly isolated rat serosal HP-MC, was a 750,000 to 1,000,000 m.w. proteoglycan containing only heparin glycosaminoglycans of 50,000 to 100,000 m.w. As assessed by electron microscopy, many of the cultured HP-MC resembled freshly isolated cells except that some secretory granules had fused with one another in some cells. These results demonstrate that the in vivo differentiated rat HP-MC maintain their histology, morphology, immunologic responsiveness, histamine content, and ability to synthesize heparin proteoglycan when co-cultured with living fibroblasts.

  5. The mast cell stabilizer sodium cromoglycate reduces histamine release and status epilepticus-induced neuronal damage in the rat hippocampus.

    PubMed

    Valle-Dorado, María Guadalupe; Santana-Gómez, César Emmanuel; Orozco-Suárez, Sandra Adela; Rocha, Luisa

    2015-05-01

    Experiments were designed to evaluate changes in the histamine release, mast cell number and neuronal damage in hippocampus induced by status epilepticus. We also evaluated if sodium cromoglycate, a stabilizer of mast cells with a possible stabilizing effect on the membrane of neurons, was able to prevent the release of histamine, γ-aminobutyric acid (GABA) and glutamate during the status epilepticus. During microdialysis experiments, rats were treated with saline (SS-SE) or sodium cromoglycate (CG-SE) and 30 min later received the administration of pilocarpine to induce status epilepticus. Twenty-four hours after the status epilepticus, the brains were used to determine the neuronal damage and the number of mast cells in hippocampus. During the status epilepticus, SS-SE group showed an enhanced release of histamine (138.5%, p = 0.005), GABA (331 ± 91%, p ≤ 0.001) and glutamate (467%, p ≤ 0.001), even after diazepam administration. One day after the status epilepticus, SS-SE group demonstrated increased number of mast cells in Stratum pyramidale of CA1 (88%, p < 0.001) and neuronal damage in dentate gyrus, CA1 and CA3. In contrast to SS-SE group, rats from the CG-SE group showed increased latency to the establishment of the status epilepticus (p = 0.048), absence of wet-dog shakes, reduced histamine (but not GABA and glutamate) release, lower number of mast cells (p = 0.008) and reduced neuronal damage in hippocampus. Our data revealed that histamine, possibly from mast cells, is released in hippocampus during the status epilepticus. This effect may be involved in the subsequent neuronal damage and is diminished with sodium cromoglycate pretreatment.

  6. Stimulation of 14-3-3 protein and its isoform on histamine secretion from permeabilized rat peritoneal mast cells.

    PubMed

    Fujii, Toshihiro; Ueeda, Takayuki

    2002-12-01

    The effect of the 14-3-3 protein, an adaptor protein of intracellular signal pathways, on histamine release from rat peritoneal mast cells was investigated. The exogenous 14-3-3 protein from bovine brain increased the Ca(2+)-dependent histamine release from permeabilized mast cells, but only slightly affected the non-permeabilized cells. Partial amino acid sequences showed that the bovine brain 14-3-3 protein contained 14-3-3beta, gamma and zeta isoforms, and that these recombinant isoforms were prepared. Among them, 14-3-3zeta was an active species while the 14-3-3beta and gamma were inactive for histamine release from the permeabilized mast cells. Approximately 15% of the histamine release was stimulated by 14-3-3zeta at 2.5 microM, and half-maximal stimulation occurred at 1 microM. Treatment of the mast cells with wortmannin or staurosporine completely inhibited the stimulatory effect on histamine release caused by Ca(2+) or Ca(2+)/14-3-3zeta, and genistein partially inhibited both stimulatory effects. PD 98059, however, had little effect on the histamine release. These results suggest the possibility that 14-3-3zeta is associated with signal transduction for degranulation of the mast cells.

  7. The use of microelectrode array (MEA) to study rat peritoneal mast cell activation.

    PubMed

    Yeung, Chi-Kong; Law, Jessica Ka-Yan; Sam, Sze-Wing; Ingebrandt, Sven; Lau, Hang-Yung Alaster; Rudd, John Anthony; Chan, Mansun

    2008-06-01

    We performed this study to demonstrate the applicability of the microelectrode array (MEA) to study electrophysiological changes of rat peritoneal mast cells in the presence of compound 48/80 under normal, Ca(2+)-free, Ca(2+)-free with EDTA, and Cl(-)-free conditions. The use of high extracellular K(+) (KCl, 150 mM), charybdotoxin (ChTX, 100 nM), and Cl(-)-free containing ChTX buffers verified that the hyperpolarizing signal was due to the activation of mainly K(+) and, to a lesser extent, Cl(-) channels. Compound 48/80 concentration-dependently shortened the latent periods (the onset of response) and increased both the spatial (the K(+) and Cl(-) hyperpolarizing field potentials, HFP) and temporal measurements (the duration of response). Ca(2+)-free buffer had no effect on the latent period of compound 48/80 but increased the HFP at high concentrations. The latent period increased while the HFP diminished when cells were equilibrated in Ca(2+)-free buffer containing EDTA. Durations of the HFP were generally longer when cells were in either Ca(2+)-free or Ca(2+)-free containing EDTA buffers than when cells were in normal buffer. The EC(50) values confirmed that effects were only affected in Ca(2+)-free buffer containing EDTA but not in Ca(2+)-free or Cl(-)-free buffers, further reinforcing the hypothesis that the presence of Ca(2+) is not essential to the action of compound 48/80. The present study is the first application of MEA to study rat peritoneal mast cells, and our results indicate that it could be of value in future pharmacological research on other non-excitable cells.

  8. The antinociception of oxytocin on colonic hypersensitivity in rats was mediated by inhibition of mast cell degranulation via Ca2+-NOS pathway

    PubMed Central

    Gong, Liping; Li, Jing; Tang, Yan; Han, Ting; Wei, Chuanfei; Yu, Xiao; Li, Jingxin; Wang, Rong; Ma, Xuelian; Liu, Kejing; Geng, Lingyun; Liu, Shaozhuang; Yan, Bing; Liu, Chuanyong

    2016-01-01

    This study was conducted to investigate the effects of oxytocin (OT) on visceral hypersensitivity/pain and mast cell degranulation and the underlying mechanisms. We found that oxytocin receptor (OTR) was expressed in colonic mast cells in humans and rats, as well as in human mast cell line-1 (HMC-1), rat basophilic leukemia cell line (RBL-2H3) and mouse mastocytoma cell line (P815). OT decreased 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced visceral hypersensitivity, colonic mast cell degranulation and histamine release after mast cell degranulation in rats. Also, OT attenuated the compound 48/80 (C48/80)-evoked histamine release in P815 cells and inward currents, responsible for the mast cell degranulation, in HMC-1, RBL-2H3 and P815 cells. Moreover, these protective effects of OT against visceral hypersensitivity and mast cell degranulation were eliminated by coadministration of OTR antagonist atosiban or a nonselective inhibitor of nitric oxide synthase (NOS), NG-Methyl-L-arginine acetate salt (L-NMMA). Notably, OT evoked a concentration-dependent increase of intracellular Ca2+ in HMC-1, RBL-2H3 and P815 cells, which was responsible for the activation of neuronal NOS (NOS1) and endothelial NOS (NOS3). Our findings strongly suggest that OT might exert the antinociception on colonic hypersensitivity through inhibition of mast cell degranulation via Ca2+-NOS pathway. PMID:27538454

  9. Rat intestinal mast cell amines are released during nitric oxide synthase inhibition in vitro

    PubMed Central

    Northover, B. J.

    1996-01-01

    Inhibition of nitric oxide synthase increases microvascular permeability in rat small intestinal villi. To determine the mechanism(s) whereby this occurs we have perfused the vasculature of rat isolated small intestines with a gelatin-containing physiological salt solution. Inclusion of N-nitro-L-argintne methyl ester (L-NAME, 100 μM) or indomethacin (1 μM) in the perfusate increased leakage of injected colloidal carbon into microvessel walls. Pre-treatment with sodium nitroprusside (10 μM) significantly reduced the effects of both L-NAME and indomethacin, whereas carbacyclin (1 μM) only reduced the effects of indomethacin. PD151242 (1 μM) showed some antagonism towards the effects of L-NAME, but nordihydroguaiaretic acid (3 μM) was inactive. Pre-tment with cyproheptadine (10 μM) reduced the effects of both L-NAME and indomethacin, and also significantly reduced background (control) colloidal carbon leakage. Small intestines from polymixin B-treated rats showed significantly reduced colloidal carbon leakage in response to L-NAME. This suggests that the leakage-enhancing effects of both L-NAME and indomethacin in this preparation may be mediated by mast cell-derived amines. PMID:18475694

  10. Cloning of cDNAs that encode human mast cell carboxypeptidase A, and comparison of the protein with mouse mast cell carboxypeptidase A and rat pancreatic carboxypeptidases

    SciTech Connect

    Reynolds, D.S.; Gurley, D.S.; Stevens, R.L.; Austen, K.F.; Serafin, W.E. Brigham and Women's Hospital, Boston, MA ); Sugarbaker, D.J. )

    1989-12-01

    Human skin and lung mast cells and rodent peritoneal cells contain a carboxypeptidase in their secretory granules. The authors have screened human lung cDNA libraries with a mouse mast cell carboxypeptidase A (MC-CPA) cDNA probe to isolate a near-full-length cDNA that encodes human MC-CPA. The 5{prime} end of the human MC-CPA transcript was defined by direct mRNA sequencing and by isolation and partial sequencing of the human MC-CPA gene. Human MC-CPA is predicted to be translated as a 417 amino acid preproenzyme which includes a 15 amino acid signal peptide and a 94-amino acid activation peptide. The mature human MC-CPA enzyme has a predicted size of 36.1 kDa, a net positive charge of 16 at neutral pH, and 86% amino acid sequence identity with mouse MC-CPA. DNA blot analyses showed that human MC-CPA mRNA is transcribed from a single locus in the human genome. Comparison of the human MC-CPA with mouse MC-CPA and with three rat pancreatic carboxypeptidases shows that these enzymes are encoded by distinct but homologous genes.

  11. Degranulation, density, and distribution of mast cells in the rat thalamus: a light and electron microscopic study in basal conditions and after intracerebroventricular administration of nerve growth factor.

    PubMed

    Florenzano, F; Bentivoglio, M

    2000-09-04

    In the adult rat brain mast cells reside selectively in the thalamus. We investigated thalamic mast cells stained by acidic toluidine blue or pinacyanol, and with histamine immunocytochemistry, focusing on their state of activity revealed by degranulation. Mast cells exhibited perivascular prevalence and high quantitative variability, between cases and in different sections, with no asymmetry or topographical selectivity in thalamic nuclei. Pinacyanol, alone or with erythrosine, stained mast cells with higher sensitivity than toluidine blue. However, toluidine blue was highly predictive of pinacyanol staining and provided the best resolution of mast cell cytoplasmic features. Histamine immunocytochemistry labeled 61% of pinacyanol-stained mast cells. Intensely toluidine blue-stained granulated cells, as well as cells exhibiting different degrees of degranulation that paralleled lighter staining, were observed. The response of thalamic mast cells to intracerebroventricular administration of nerve growth factor (NGF) and control cytochrome-c injections was evaluated after 2, 24, and 72 hours. No obvious changes in mast cell number or distribution were found after treatment, but massive degranulation was frequently observed after NGF administration. Significant decrease of staining intensity of mast cells, supporting enhanced degranulation, was documented in NGF-treated animals by quantitative image analysis. Ultrastructural features of mast cell degranulation, with granule coalescence and matrix dissolution, were detected in untreated and NGF-treated cases. The findings point out that mast cells are active in the thalamus in basal conditions and that NGF has the potential to elicit long-lasting degranulation of thalamic mast cells in vivo, exerting a direct effect and/or priming these cells to react to endogenous stimuli.

  12. Vitamin A and the biosynthesis of sulphated mucopolysaccharides. Experiments with rats and cultured neoplastic mast cells

    PubMed Central

    Thomas, D. B.; Pasternak, C. A.

    1969-01-01

    1. The uptake and incorporation of [35S]sulphate into mucopolysaccharides by colon and duodenum in vitro are unaffected by the vitamin A status of the animals. 2. Uptake and incorporation in vivo are unaffected at 4hr. after injection of [35S]sulphate, but at later times are decreased in some tissues of vitamin A-deficient animals. 3. The rate of removal of 35S from blood, its rate of appearance in urine, the plasma concentration of sulphate and the uronic acid content of several tissues are not significantly altered in vitamin A deficiency. 4. These results, and direct measurement of 35S in mucopolysaccharides at various times after injection of [35S]sulphate, suggest that the synthesis of mucopolysaccharides is unaffected but that their turnover is increased in vitamin A deficiency. 5. Neither the growth rate of, nor the incorporation of [35S]sulphate into heparin by, P815Y and HC cultured neoplastic mast cells is decreased when the horse serum necessary for growth is treated with ultraviolet light or is replaced by serum from vitamin A-deficient rats. 6. The addition of citral is no more toxic to growth rate or to incorporation of 35S than is the addition of vitamin A itself. 7. It is concluded that neoplastic mast cells in culture do not require vitamin A for growth or for the synthesis of heparin. 8. None of these results is compatible with the view that vitamin A or a derivative is directly involved in the biosynthesis of sulphated mucopolysaccharides. PMID:4237718

  13. Intestinal mucosal mast cells from rats infected with Nippostrongylus brasiliensis contain protease-resistant chondroitin sulfate di-B proteoglycans

    SciTech Connect

    Stevens, R.L.; Lee, T.D.G.; Seldin, D.C.; Austen, K.F.; Befus, A.D.; Bienenstock, J.

    1986-07-01

    Rats infected with the helminth Nippostrongylus brasiliensis were injected i.p. with 2 mCi of (/sup 35/S) sulfate on days 13, 15, 17, and 19 after infection. The intestines were removed from animals on day 20 or 21 after infection, the intestinal cells were obtained by collagenase treatment and mechanical dispersion of the tissue, and the /sup 35/S-labeled mucosal mast cells (MMC) were enriched to 60 to 65% purity by Percoll centrifugation. The isolated proteoglycans were of approx. 150,000 m.w., were resistant to pronase degradation, and contained highly sulfated chondroitin sulfate side chains. The presence in normal mammalian cells of chondroitin sulfate proteoglycans that contain a high percentage of the unusual disulfated di-B disaccharide has not been previously reported. The rat intestinal MMC proteoglycans are the first chondroitin sulfate proteoglycans that have been isolated from an enriched populations of normal mast cells. They are homologous to the chondroitin sulfate-rich proteoglycans of the transformed rat basophilic leumekia-1 cell and the cultured interleukin 3-dependent mouse bone marrow-derived mast cell, in that these chondroitin sulfate proteoglycans are all highly sulfated, protease-resistant proteoglycans.

  14. Simultaneous detection of histamine release and lactate production in rat mast cells induced by compound 48/80 using sup 1 H NMR

    SciTech Connect

    Yoshizaki, Kazuo; Arizono, Naoki )

    1991-04-01

    {sup 1}H NMR spectroscopy was used to evaluate histamine release and lactate production in intact mast cells isolated from rats. The resonance lines of the aromatic histamine protons in mast cells, detected by the selective spin-excitation technique, were broader and located in a lower magnetic field than those in free histamine solution. When exocytosis of mast-cell granules was induced by compound 48/80, free histamine appeared, with a corresponding decrease in the amount of histamine in the mast cells; the lactate signal was also detected in the spectrum. On the addition of compound 48/ 80, there was a further release of histamine from mast cells, accompanied by further production of lactate. This result indicates that the mechanisms which induce the exocytosis of granules, and/or the events following exocytosis, activate glycolysis.

  15. Effect of Prolyl-Glycyl-Proline (PGP) and Its Acetylated Form (N-AcPGP) on Calcium Level in the Cytoplasm of Rat Peritoneal Mast Cells.

    PubMed

    Bondarenko, N S; Kurenkova, A D; Nikishin, D A; Umarova, B A

    2016-08-01

    Tripeptide glycyl-prolyl-proline (PGP), a regulatory peptide of the glyproline family, possesses a pronounced anti-inflammatory effect primarily due to its ability to prevent secretion of the proinflammatory mediator histamine by rat peritoneal mast cells. Activation of mast cell with synacthen (ACTH1-24) and substance 48/80 leads to an increase in intracellular calcium concentration. Pretreatment of mast cells with PGP prevented calcium entry into the cytoplasm from both intercellular space and intracellular stores. Acetylated peptide (N-AcPGP) produced a similar effect on histamine release and intracellular calcium content in mast cells activated with synacthen. These findings indicate that both forms of the peptide can stabilize mast cells and prevent intracellular calcium increase.

  16. Study on the Dynamic Compound Structure Composed of Mast Cells, Blood Vessels, and Nerves in Rat Acupoint

    PubMed Central

    Mingfu, Luo; Xiaotong, Dong; Xiaojing, Song; Jin, Jiang; Jinling, Zhann; Ying, Han

    2013-01-01

    Background. Circulation system, immunity system, and nervous system have a close relationship with meridian phenomen. However, there is still lack of the results of dynamic changes of these structures in acupoint. The aim of this study is to explore the interrelationship by composite staining techniques. Methodology/Principal Findings. Twenty rats were separated into electroacupuncture group (EA) and control group (Con) randomly. In EA group, the Zusanli and Weishu were stimulated with the 0.1 mA for 25 min. The tissue of these acupoints was double-stained with acetylcholinesterase and Toluidine blue. The compound structure of mast cells, nervous fibers, and mast cells in the acupoint was observed. Conclusions/Significance. The blood vessels, mast cells and acetylcholinesterase responded nerves were clearly observed in acupoint tissues. EA can result in the mast cell recruitment and migration along the blood vessels and nervous bundle, which conformed the dynamic compound structure and played important roles in acupuncture. PMID:23878591

  17. Calcium- and guanine-nucleotide-dependent exocytosis in permeabilized rat mast cells. Modulation by protein kinase C.

    PubMed Central

    Koopmann, W R; Jackson, R C

    1990-01-01

    We have used a digitonin-permeabilized cell system to study the signal transduction pathways responsible for stimulus-secretion coupling in the rat peritoneal mast cell. Conditions were established for permeabilizing the mast cell plasma membrane without disrupting secretory vesicles. Exocytotic release of histamine from digitonin-permeabilized cells required a combination of micromolar concentrations of Ca2+ and the stable guanine nucleotide analogue guanosine 5'-[gamma-thio]triphosphate (GTP[S]), but was independent of exogenous ATP. In the presence of 40 microM-GTP[S], exocytosis was half-maximal at 1.3 microM-Ca2+ and maximal at 10 microM-Ca2+; GTP[S] alone (100 microM) had no effect on histamine release in the absence of added Ca2+. In the presence of 10 microM free Ca2+, 5 microM-GTP[S] was required for half-maximal exocytosis. To examine the possible role of protein kinase C (PKC) in exocytosis, we utilized 12-O-tetradecanoylphorbol 13-acetate (TPA) to activate PKC and studied its effect on histamine release from permeabilized mast cells. Cells that had been incubated with TPA (25 nM for 5 min) exhibited increased sensitivity to both GTP[S] and Ca2+. The PKC inhibitor staurosporine blocked the effect of TPA without inhibiting normal exocytosis in response to the combination of GTP[S] and Ca2+. In addition, down-regulation of mast-cell PKC by long-term TPA treatment (25 nM for 20 h) blocked the ability of the cells to respond to TPA and inhibited exocytosis in response to Ca2+ and GTP[S] by 40-50%. These results suggest that the sensitivity of the exocytotic machinery of the mast cell can be altered by PKC-catalysed phosphorylation events, but that activation of PKC is not required for exocytosis to occur. Images Fig. 7. PMID:1689146

  18. Pyrazolopyrimidines: synthesis, effect on histamine release from rat peritoneal mast cells and cytotoxic activity.

    PubMed

    Quintela, J M; Peinador, C; Moreira, M J; Alfonso, A; Botana, L M; Riguera, R

    2001-04-01

    A series of 1H-pyrazolo[3,4-d]pyrimidines (3--6) substituted at positions 1 (R(1)=Ph, H, tert-butyl and ribosetribenzoate), 4 (R(2)=chlorine, nitrogen and oxygen nucleophiles), and 6 (dimethylamino) have been synthesized and their effect on the release of histamine from rat peritoneal mast cells measured. After chemical stimulation, (polymer 48/80), several compounds (i.e. 3b, 4a, 4b, 4d, 4g, 5a), produce inhibition two to three times higher (40--60%) than DSCG but this action is lower after preincubation. 4b (R(1)=Ph, R(2)=NHCH(2)Ph; 50--70% inhibition) and 5a (R(1)=H, R(2)=OMe; 50--55% inhibition) are the most active ones in both experiments. With ovoalbumin as stimulus, several pyrazolopyrimidines show inhibition similar to DSCG, the most active compounds being 6a--d (IC(50)=12--16 microM; R(1)=ribosetribenzoate, R(2)=methoxy and amino). Compounds 4e (R(1)=t-butyl, R(2)=OMe) and 4g (R(1)=t-butyl, R(2)=piperidino) are inducers of the release of histamine (60 and 150% increase). Compounds 4b and 4c showed cytotoxic activity (IC(50)=1 microg/mL) to HT-29 human colon cancer cells.

  19. Acute stress modulates the histamine content of mast cells in the gastrointestinal tract through interleukin-1 and corticotropin-releasing factor release in rats.

    PubMed

    Eutamene, Helene; Theodorou, Vassilia; Fioramonti, Jean; Bueno, Lionel

    2003-12-15

    Stress results in activation of the hypothalamic pituitary adrenal axis and affects illnesses such as neuroinflammatory syndrome. In vivo acute stress (restraint stress) induces gastrointestinal function disturbances through colonic mast cell activation. This study investigated the effect of acute stress in histamine content of colonic mast cells, and the central role of interleukin-1 (IL-1) and corticotropin-releasing factor (CRF) in this effect. After a restraint stress session colonic segments were isolated and submitted to three protocols: (i) determination of histamine levels by radioimmunoassay (RIA) after incubation with 48/80 compound, (ii) evaluation by histology of mucosal mast cell (MMC) number and (iii) determination of histamine immunoreactivity of MMC. These procedures were conducted (1) in sham or stressed rats, (2) in stressed rats previously treated with intracerebroventricular (I.C.V.) IL-1ra or alpha-helical CRF9-41, (3) in naive rats pretreated with I.C.V. rhIL-1beta or CRF and (4) in rats treated with central IL-1beta and CRF plus alpha-helical CRF and IL-1ra, respectively (cross-antagonism reaction). Acute stress increases histamine content in colonic mast cells, without degranulation. I.C.V. pretreatment with IL-1ra or alpha-helical CRF9-41 blocked stress-induced mast cell histamine content increase. Both I.C.V. rhIL-1beta and CRF injections reproduced the stress-linked changes. I.C.V. treatment with CRF antagonist blocked I.C.V. rhIL-1beta-induced mast cell histamine content increase, whereas central IL-1ra did not affect stress events induced by I.C.V. CRF administration. These results suggest that in rats acute stress increases colonic mast cell histamine content. This effect is mediated by the release in cascade in the brain first of IL-1 and secondly of CRF.

  20. The effects of histamine and prostaglandin D2 on rat mast-cell cyclic AMP and mediator release

    SciTech Connect

    Wescott, S.; Kaliner, M.

    1981-11-01

    The possibility that histamine may play a functional role in modulating mast-cell secretion, as has been suggested for basophil degranulation, has both physiologic and pharmacologic implications. Therefore the capacity of histamine to influence rat peritoneal mast-cell (RPMC) cyclic AMP levels and reversed anaphylatic degranulation as reflected in the release of 3H-serotonin (5-HT) was examined. To ascertain that RPMC were functionally responsive to exogenous hormonal stimulation, assessment of prostaglandin (PG) D2 effects on cyclic AMP and 5-HT release were determined in parallel. Although PGD2 (100 microM) increased cyclic AMP and inhibited 5-HT release in the presence of 50 microM aminophylline, histamine (up to 1000 microM) was ineffective was ineffective in both. However, 1000 microM histamine in the presence of 500 microM aminophylline was capable of transiently increasing RPMC cyclic AMP (for 15 to 30 sec) and under these conditions of suppressing 5-HT release. The receptor subtype involved in the suppressive actions of histamine appeared to be of the H-1 type as reflected in the capacity of specific H-1 agonists to reproduce the inhibition of 5-HT release, whereas neither H-2 agonists nor H-2 antagonists had any influence. Thus, under conditions in which phosphodiesterase enzymatic action is impaired, histamine in extremely high concentrations is able to modulate mast-cell secretion. However, it seems very unlikely that this action of histamine has any physiologic significance.

  1. Role of mast cells in wound healing process after glass - fiber composite implant in rats

    PubMed Central

    Rodella, L F; Rezzani, Rita; Buffoli, Barbara; Bonomini, Francesca; Tengattini, Sandra; Laffranchi, Laura; Paganelli, C; Sapelli, P L; Bianchi, Rossella

    2006-01-01

    Glass-fiber composites are frequently used in dentistry. In order to evaluate their biocompatibility we tested, in an experimental model “in vivo”, their tissue response pointing our attention on presence of mast cells (MCs) and fibrotic process. Sprague Dawley rats were used for the experimental design. The fibers were introduced in a subcutaneous pocket along the middle dorsal line between the two scapulas for 7, 14 or 21 days. At the end of the treatments the skins were excised and then processed for Toluidine Blue, to determine the presence of MCs, and Picrosirius Red staining, to evaluate the presence of fibrotic tissue. Our preliminary results showed and increase of both MC number and deposition of collagen type I, which characterized the fibrotic tissue. So, subsequent aims of our study were to evaluate the role played by MCs in tissue fibrosis and to give a possible explanation regarding the mechanisms that were responsible of biological response observed, through the analyses of some proteins, such as metalloproteinase-2 (MMP-2), its inhibitor (TIMP-2) and transforming growth factor-β (TGF-β). Our data confirmed the involvement of TGF-β, released by MCs, in the disruption of the equilibrium between MMP-2 and TIMP-2 that were implicated in the enhancement of fibrosis. In summary, this study demonstrate that this type of materials induced an inflammatory response at the site of implant and help to clarify what type of mechanism and which proteins are involved in this biological response. Nevertheless, more extensive investigations are in progress to better evaluate the inflammatory process. PMID:17125597

  2. Biochemical and functional characterization of glycosaminoglycans released from degranulating rat peritoneal mast cells: Insights into the physiological role of endogenous heparin.

    PubMed

    Lever, Rebecca; Smailbegovic, Amir; Riffo-Vasquez, Yanira; Gray, Elaine; Hogwood, John; Francis, Stephen M; Richardson, Neville V; Page, Clive P; Mulloy, Barbara

    2016-12-01

    The properties of commercially prepared heparin as an anticoagulant and antithrombotic agent in medicine are better understood than is the physiological role of heparin in its native form, where it is uniquely found in the secretory granules of mast cells. In the present study we have isolated and characterised the glycosaminoglycans (GAGs) released from degranulating rat peritoneal mast cells. Analysis of the GAGs by NMR spectroscopy showed the presence of both heparin and the galactosaminoglycan dermatan sulphate; heparinase digestion profiles and measurements of anticoagulant activity were consistent with this finding. The rat peritoneal mast cell GAGs significantly inhibited accumulation of leukocytes in the rat peritoneal cavity in response to IL-1β (p < 0.05, n = 6/group), and inhibited adhesion and diapedesis of leukocytes in the inflamed rat cremasteric microcirculation in response to LPS (p < 0.001, n = 4/group). FTIR spectra of human umbilical vein endothelial cells (HUVECs) were altered by treatment of the cells with heparin degrading enzymes, and restored by the addition of exogenous heparin. In conclusion, we have shown that rat peritoneal mast cells contain a mixture of GAGs that possess anticoagulant and anti-inflammatory properties.

  3. Pharmacological inhibition of outwardly rectifying Cl- currents in rat peritoneal mast cells: a comparison of different stilbene derivatives.

    PubMed

    Roloff, Tim; Ziegler, Albrecht; Heber, Dieter; Seebeck, Jörg

    2003-10-08

    Diethylstilbestrol and other stilbene derivatives can provide some inhibition of the outwardly rectifying Cl- current (I(Cl-,OR)) in rat peritoneal mast cells. In order to elucidate structure-activity relationships of diethylstilbestrol, 12 stilbenes as well as 17beta-estradiol and hexestrol were tested in rat peritoneal mast cells using the nystatin-perforated patch approach of the whole-cell patch-clamp technique. Since trans-stilbene showed no effect, the substituents of diethylstilbestrol must be of importance. The introduction of only one hydroxy group in trans-stilbene produced potent inhibition of the I(Cl-,OR) (IC50: 3.3 microM). But in contrast, resveratrol with hydroxy groups at positions 4, 3', and 5' as well as methoxy substituted stilbene derivatives and 17beta-estradiol were ineffective. On the other hand, hexestrol potently inhibited I(Cl-,OR) indicating that the aromatic ring systems can also be connected by an ethyl bridge. In summary, a hydroxy group at position 4 (or 4') is a prerequisite for diethylstilbestrol-mediated inhibition of I(Cl-,OR).

  4. Isolation of rat lung mast cells for purposes of one-week cultivation using novel Percoll variant Percoll PLUS.

    PubMed

    Kubrycht, J; Maxová, H; Nyč, O; Vajner, L; Novotná, J; Hezinová, A; Trnková, A; Vrablová, K; Vytášek, R; Valoušková, V

    2011-01-01

    Prolonged cultivation of separated rat lung mast cells (LMC) in vitro is necessary to better investigate a possible role of LMC in different stages of tissue remodeling induced by hypoxia. Rat lung mast cells (LMC) were separated using a protocol including an improved proteolytic extraction and two subsequent density gradient separations on Ficoll-Paque PLUS and a new generation of Percoll, i.e. Percoll PLUS. Instead of usual isotonic stock Percoll solution, an alternative "asymptotically isotonic" stock solution was more successful in our density separation of LMC on Percoll PLUS. Separated cells were cultivated for six days in media including stem cell factor, interleukins IL-3 and IL-6, and one of two alternative mixtures of antibiotics. These cultivations were performed without any contamination and with only rare changes in cell size and morphology. Model co-cultivation of two allogenic fractions of LMC often caused considerable rapid changes in cell morphology and size. In contrast to these observations no or rare morphological changes were found after cultivation under hypoxic conditions. In conclusions, we modified separation on Percoll PLUS to be widely used, altered LMC separation with respect to purposes of long-lasting cultivation and observed some model morphological changes of LMC.

  5. Intestinal mast cells and eosinophils in relation to Strongyloides ratti adult expulsion from the small and large intestines of rats.

    PubMed

    Shintoku, Y; Kadosaka, T; Kimura, E; Takagi, H; Kondo, S; Itoh, M

    2013-04-01

    Mucosal mast cells (MMC) play a crucial role in the expulsion of Strongyloides ratti adults from the small intestine of mice. We reported the large intestinal parasitism of S. ratti in rats, and there has been no report on MMC in the large intestine of the natural host. We studied kinetics of MMC, together with eosinophils, in the upper and lower small intestines, caecum and colon of infected rats. Two distinct phases of mastocytosis were revealed: one in the upper small intestine triggered by stimulation of 'ordinary' adults, and the other in the colon stimulated by 'immune-resistant' adults that started parasitizing the colon around 19 days post-infection. In all 4 intestinal sites, the MMC peaks were observed 5-7 days after the number of adult worms became the maximum and the height of MMC peaks appeared to be dependent on the number of parasitic adults, suggesting an important role played by worms themselves in the MMC buildup.

  6. Mast-cell-releasing tryptase triggers acute lung injury induced by small intestinal ischemia-reperfusion by activating PAR-2 in rats.

    PubMed

    Gan, Xiaoliang; Liu, Dezhao; Huang, Pinjie; Gao, Wanling; Chen, Xinzhi; Hei, Ziqing

    2012-06-01

    Mast cell has been demonstrated to be involved in the small intestinal ischemia-reperfusion (IIR) injury, however, the precise role of tryptase released from mast cell on acute lung injury(ALI) induced by IIR remains to be elucidated, our study aimed to observe the roles of tryptase on ALI triggered by IIR and its underlying mechanism. Adult SD rats were randomized into sham-operated group, sole IIR group in which rats were subjected to 75 min superior mesenteric artery occlusion followed by 4 h reperfusion, or IIR being respectively treated with cromolyn sodium, protamine, and compound 48/80. The above agents were, respectively, administrated intravenously 5 min before reperfusion. At the end of experiment, lung tissue was obtained for assays for protein expressions of tryptase and mast cell protease 7 (MCP7) and protease-activated receptor 2 (PAR-2). Pulmonary mast cell number and levels of IL-8 were quantified. Lung histologic injury scores and lung water content were measured. IIR resulted in lung injury evidenced as significant increases in lung histological scores and lung water contents, accompanied with concomitant increases of expressions of tryptase and MCP7, and elevations in PAR-2 expressions and IL-8 levels in lungs. Stabilizing mast cell with cromolyn sodium and inhibiting tryptase with protamine significantly reduced IIR-mediated ALI and the above biochemical changes while activating mast cell with compound 48/80 further aggravated IIR-mediated ALI and the increases of above parameters. Tryptase released from mast cells mediates ALI induced by intestinal ischemia-reperfusion by activating PAR-2 to produce IL-8.

  7. Prostaglandin D2 generation by rat peritoneal mast cells stimulated with Datura stramonium agglutinin and its inhibition by haptenic sugar and wheat germ agglutinin.

    PubMed

    Suzuki-Nishimura, Tamiko; Uchida, Masaatsu K

    2002-09-01

    The production of prostaglandin D2 (PGD2) by rat peritoneal mast cells incubated with N-acetyl glucosamine (GlcNAc) oligomer-specific Datura stramonium agglutinin (DSA) for 10 min in the presence of 0.3 mM Ca2+ was examined. Previously, our group reported that the incubation of rat mast cells with DSA (5 - 100 microg/ml) under similar conditions resulted in a calcium influx and histamine release via a pertussis toxin-sensitive G-protein pathway of the mast cells, and the histamine release was inhibited by haptenic sugar chitooligosaccharides or GlcNAc-specific lectin wheat germ agglutinin (WGA) (K. Matsuda et al., Jpn J Pharmacol 66, 195 - 204 (1994)). DSA (5 - 100 microg/ml) dose-dependently stimulated the mast cells to generate PGD2. Chitooligosaccharides (1% w/v) and WGA (100 microg/ml) inhibited the production of PGD2 induced by 100 microg/ml of DSA, suggesting that the effect of DSA is sugar-specific. A prostaglandin G/H synthase inhibitor NS-398 (N-[cyclohexyloxy-4-nitrophenyl] methanesulfonamide) (10 microM) inhibited the formation of PGD2 induced by DSA (20 microg/ml). These results suggest that the binding of DSA to the corresponding sugar residues on the mast cell surface mediates the signaling of the prostaglandin G/H synthase pathway.

  8. Effect of 8-methoxypsoralen plus long-wave ultraviolet (PUVA) radiation on mast cells. II. In vitro PUVA inhibits degranulation of rat peritoneal mast cells induced by compound 48/80

    SciTech Connect

    Toda, K.; Danno, K.; Tachibana, T.; Horio, T.

    1986-07-01

    Rat peritoneal mast cells incubated with a histamine liberator, compound 48/80, showed a significantly reduced capacity for releasing histamine following in vitro treatment with 0.1 micrograms/ml of 8-methoxypsoralen (8-MOP) plus 1-5 J/cm2 of long-wave ultraviolet (UVA) irradiation (PUVA). No remarkable inhibition in histamine release was observed in the cells treated with 8-MOP only. Irradiation with 5 J/cm2 of UVA alone exerted an inhibitory effect on histamine release, to a lesser extent than PUVA. PUVA irradiation did not bring any decrease in cell viability or any spontaneous release of histamine from irradiated cells as shown by phase-contrast microscopy and by histamine assay, respectively. These results suggest that PUVA treatment may cause a noncytotoxic disturbance at mast cell membranes or on surface receptors, leading to a decreased capacity for secreting chemical mediators.

  9. The effects of thermal stimuli on intracellular calcium change and histamine releases in rat basophilic leukemia mast cells

    NASA Astrophysics Data System (ADS)

    Wu, Zu-Hui; Zhu, Dan; Chen, Ji-Yao; Zhou, Lu-Wei

    2012-05-01

    The effects of thermal stimuli on rat basophilic leukemia mast cells were studied. The cells in calcium-contained or calcium-free buffers were thermally stimulated in the temperature range of 25-60 °C. The corresponding calcium ion concentration in cells [Ca2+]i as well as the released histamine from cells was measured with fluorescence staining methods. The ruthenium red (RR), a block of membrane calcium channels (transient receptor potential family V (TRPV)), was used in experiments. Under the stimulus of 25-50 °C, no significant difference on [Ca2+]i was found between these three groups of the cells in calcium-contained buffer without or with RR and cells in calcium-free saline, indicating that the increased calcium in cytosol did not result from the extracellular buffer but came from the intracellular calcium stores. The [Ca2+]i continuously increased under the temperature of 50-60 °C, but the RR and calcium-free saline can obviously diminish the [Ca2+]i increase at these high temperatures, reflecting that the opening of the TRPV2 channels leads to a calcium influx resulting in the [Ca2+]i increment. The histamine release also became significant in these cases. Since the released histamine is a well-known mediator for the microcirculation promotion, the histamine release from mast cells could be one of the mechanisms of thermal therapy.

  10. Characteristics of histamine release from rat mast cells in relation to the valency of the stimulating ligand.

    PubMed Central

    Healicon, R M; Foreman, J C

    1986-01-01

    The relationship between the valency of a ligand and the subsequent characteristics of histamine release was investigated in rat peritoneal mast cells. The cells were passively sensitized to the DNP hapten and a series of DNP-human serum albumin conjugates of known valency were used to induce histamine release. The rate of release of histamine induced by these conjugates was independent of the DNP/HSA ratio when the ratio was between 71.3 and 7.2. Marked slowing of the release occurred as the ratio was reduced below 7.2. The rate of desensitization of the cells slowed as a continuous function as the DNP/HSA ratio was reduced. 45Calcium uptake measurements showed that the changes in histamine release were paralleled by changes in the membrane permeability to calcium. The rate of release of histamine from mast cells and the rate of desensitization of the cells are discussed in terms of the size of IgE receptor complexes on the cell membrane. PMID:2420710

  11. In vivo effect of the lipido-sterolic extract of Serenoa repens (Permixon) on mast cell accumulation and glandular epithelium trophism in the rat prostate.

    PubMed

    Mitropoulos, Dionisios; Kyroudi, Aspasia; Zervas, Anastasios; Papadoukakis, Stefanos; Giannopoulos, Aris; Kittas, Christos; Karayannacos, Panagiotis

    2002-04-01

    The Serenoa repens lipido-sterolic extract (SRLSE, Permixon, Pierre Fabre Medicament, Castres, France) is used to treat benign prostate hyperplasia. We studied the in vivo effect of SRLSE on mast cell accumulation and the histological characteristics of the rat ventral prostate. Adult Wistar rats received either tocopherol or SRLSE (50 and 100 mg/kg body weight, respectively) every second day for 90 days. Histological features were studied in hematoxylin-eosin stained tissue sections while mean mast cell numbers were determined in Giemsa-stained sections. The central region of the ventral prostate in treated animals showed significant changes with acinar epithelium becoming flat or low cuboidal. In the same region, mean mast cell number per optical field in the control, low-dose and high-dose groups were, respectively, 4.7+/-0.7, 3.4+/-1.0 and 2.4+/-0.6, showing a dose-dependent, statistically significant decrease. Administering SRLSE significantly reduces mast cell accumulation and provokes epithelium atrophy within the central area of the rat ventral prostate. These phenomena may participate in the clinical activity of the drug.

  12. Effects of melanin-induced free radicals on the isolated rat peritoneal mast cells

    SciTech Connect

    Ranadive, N.S.; Shirwadkar, S.; Persad, S.; Menon, I.A.

    1986-03-01

    Pheomelanin from human red hair (RHM) produces considerably more cellular damage in Ehrlich ascites carcinoma cells when subjected to radiations of wavelength 320-700 nm than eumelanin from black hair (BHM). Irradiation of RHM generated large amounts of superoxide while BHM did not produce detectable amounts of superoxide. The present investigations describe the effects of irradiation of mast cells in the presence of various natural and synthetic melanins. Irradiation of mast cells in the presence of RHM and red hair melanoprotein released large amounts of histamine while BHM and synthetic melanins prepared from dopa, cysteinyldopa, or a mixture of dopa and cysteinyldopa did not release histamine. The release of histamine at lower concentrations of RHM was not accompanied by the release of /sup 51/Cr from chromium-loaded cells, suggesting that this release was of noncytotoxic nature. On the other hand, the release of histamine at higher concentrations of RHM was due to cell lysis since both histamine and cytoplasmic marker /sup 51/Cr were released to the same extent. The release evoked by large concentration RHM was not inhibited by superoxide dismutase or catalase. This suggests that the cell lysis under these conditions was not due to H/sub 2/O/sub 2/ or O-2. The finding that mast cells release histamine when irradiated in the presence of RHM suggests that the immediate and late-phase reactions seen in sunburn may in part be due to the release of mediators from these cells.

  13. Release of the mucosal mast cell granule chymase, rat mast cell protease-II, during anaphylaxis is associated with the rapid development of paracellular permeability to macromolecules in rat jejunum

    PubMed Central

    1995-01-01

    The soluble granule chymase, rat mast cell protease-II (RMCP-II), is abundantly expressed in intestinal mucosal mast cells (MMC) but its function is not known. One hypothesis is that RMCP-II degrades the epithelial basement membrane and promotes the loss of enterocytes typically associated with type I hypersensitivity reactions in the rat. To test this hypothesis more directly, ex vivo perfusion of the cranial mesenteric artery and jejunal lumen was used to monitor the anaphylactic release of RMCP-II and its effects on mucosal permeability and epithelial integrity. Within 2 min of intravascular challenge with soluble adult Nippostrongylus brasiliensis worm antigen there was a 1,000-fold (P < 0.02) increase in the concentration of RMCP-II in the vascular perfusate from the jejunum of Nippostrongylus-sensitized rats but not the controls. Similarly, translocation of RMCP-II into the gut lumen increased 10-fold (P < 0.02) after 2 min only in worm antigen- challenged immune rats. Using an identical protocol, but incorporating Evans blue-labeled human serum albumin (EB-HSA) in the vascular perfusate, the timing of the release of RMCP-II into the two compartments was very similar to the first experiment and furthermore the translocation of EB-HSA increased 18-fold (P < 0.05) after 4 min in sensitized rats challenged with worm antigen. To examine the effects of RMCP-II more directly 1 mg of the highly purified chymase was introduced into the cranial mesenteric artery in ex vivo perfused normal rats. A significant (P < 0.05) 70-fold increase in concentration of RMCP-II in jejunal perfusate occurred after 6 min. In a repeat dose- response experiment, infusion of 0.375, 0.75, or 1.5 mg of RMCP-II, together with EB-HSA, established that the cumulative amounts of RMCP- II and EB-HSA translocated from the vasculature to the gut lumen in each perfusion (during the 10-min period of RMCP-II infusion) were significantly correlated. Analysis of intestinal perfusates by SDS-PAGE and

  14. Prevention of ischemia-reperfusion injury in a rat skin flap model: the role of mast cells, cromolyn sodium, and histamine receptor blockade.

    PubMed

    Cordeiro, P G; Lee, J J; Mastorakos, D; Hu, Q Y; Pinto, J T; Santamaria, E

    2000-02-01

    The objective of this study was to examine the role of mast cells and their principal product, histamine, in ischemia/reperfusion injury. Cromolyn sodium, diphenhydramine, and cimetidine were administered to ischemic flaps just before reperfusion and evaluated for flap survival, mast cell count, neutrophil count, and myeloperoxidase levels. Epigastric island skin flaps were elevated in 49 rats; they were rendered ischemic by clamping the artery for 10 hours. Thirty minutes before reperfusion, the rats were treated with intraperitoneal saline (n = 11), cimetidine (n = 11), diphenhydramine (n = 11), or cromolyn sodium (n = 10). Flap survival was evaluated at 7 days. Neutrophil counts, mast cell counts, and myeloperoxidase levels were evaluated 12 hours after reperfusion. Flap necrosis in the sham group of animals (n = 6) was 0.0 percent, as expected, whereas the control group (saline-treated animals) had 47.3+/-33.4 percent necrosis. Animals treated with diphenhydramine and cimetidine demonstrated a significant decrease in flap necrosis to 17.7+/-8.8 percent and 19.4+/-14.7 percent, respectively. This protective effect was not seen with cromolyn sodium (44.3+/-35.6 percent). Both neutrophil and mast cell counts were significantly decreased in flaps from antihistamine-treated and sham animals versus both saline- and cromolyn sodium-treated groups. The administration of diphenhydramine and cimetidine before reperfusion can significantly reduce the extent of flap necrosis and the neutrophil and mast cell counts caused by ischemia/reperfusion. This protective effect is not seen with cromolyn sodium. The protective effect of antihistamines on flap necrosis might be related to the decrease in neutrophils and, possibly, mast cells within the flap.

  15. Structure-activity relationship of a series of 17 parabens and related compounds for histamine release in rat peritoneal mast cells and skin allergic reaction in guinea pigs.

    PubMed

    Uramaru, Naoto; Inoue, Toshio; Watanabe, Yoko; Shigematsu, Hidenari; Ohta, Shigeru; Kitamura, Shigeyuki

    2014-02-01

    Parabens, which are a homologous series of esters of p-hydroxybenzoic acid, have been used as preservatives in cosmetics, medicines and foods because of their antimicrobial activity. However, parabens in cosmetics have been suspected to cause allergic contact dermatitis. In this study, we examined paraben-induced histamine release from rat peritoneal mast cells and skin reaction in guinea pigs using a series of 17 parabens with different alcohol side chains, ranging from methylparaben to dodecylparaben. Octylparaben showed the greatest histamine release-inducing activity from mast cells, and the activity was decreased in shorter- and longer-side-chain parabens. Octyl benzoate, octyl o-hydroxybenzoate and phenyloctane caused no significant degranulation of mast cells, whereas octyl m-hydroxybenzoate, octyl p-hydroxybenzoate and octyl phenol induced concentration-related degranulation. Metabolites of these parabens (p-hydroxybenzoic acid and alcohols) did not show histamine release-inducing activity. In the guinea pig skin reaction test, heptylparaben induced a typical strong skin reaction, while butylparaben induced a typical weak skin reaction, and methylparaben and dodecylparaben were inactive. Metabolites of parabens (p-hydroxybenzoic acid and alcohols) were also inactive. These results indicate that interaction of parabens with rat mast cells requires a minimum length and adequate lipophilicity of the alkyl side chain. Since metabolites of parabens were inactive, parabens appear to be direct-acting allergens.

  16. Dectin-1-mediated Signaling Leads to Characteristic Gene Expressions and Cytokine Secretion via Spleen Tyrosine Kinase (Syk) in Rat Mast Cells*

    PubMed Central

    Kimura, Yukihiro; Chihara, Kazuyasu; Honjoh, Chisato; Takeuchi, Kenji; Yamauchi, Shota; Yoshiki, Hatsumi; Fujieda, Shigeharu; Sada, Kiyonao

    2014-01-01

    Dectin-1 recognizes β-glucan and plays important roles for the antifungal immunity through the activation of spleen tyrosine kinase (Syk) in dendritic cells or macrophages. Recently, expression of Dectin-1 was also identified in human and mouse mast cells, although its physiological roles were largely unknown. In this report, rat mast cell line RBL-2H3 was analyzed to investigate the molecular mechanism of Dectin-1-mediated activation and responses of mast cells. Treatment of cells with Dectin-1-specific agonist curdlan induced tyrosine phosphorylation of cellular proteins and the interaction of Dectin-1 with the Src homology 2 domain of Syk. These responses depended on tyrosine phosphorylation of the hemi-immunoreceptor tyrosine-based activation motif in the cytoplasmic tail of Dectin-1, whereas they were independent of the γ-subunit of high-affinity IgE receptor. DNA microarray and real-time PCR analyses showed that Dectin-1-mediated signaling stimulated gene expression of transcription factor Nfkbiz and inflammatory cytokines, such as monocyte chemoattractant protein-1, IL-3, IL-4, IL-13, and tumor necrosis factor (TNF)-α. The response was abrogated by pretreatment with Syk inhibitor R406. These results suggest that Syk is critical for Dectin-1-mediated activation of mast cells, although the signaling differs from that triggered by FcϵRI activation. In addition, these gene expressions induced by curdlan stimulation were specifically observed in mast cells, suggesting that Dectin-1-mediated signaling of mast cells offers new insight into the antifungal immunity. PMID:25246527

  17. The Effects of Electrical Stimuli on Calcium Change and Histamine Release in Rat Basophilic Leukemia Mast Cells

    NASA Astrophysics Data System (ADS)

    Zhu, Dan; Wu, Zu-Hui; Chen, Ji-Yao; Zhou, Lu-Wei

    2013-06-01

    We apply electric fields at different frequencies of 0.1, 1, 10 and 100 kHz to the rat basophilic leukemia (RBL) mast cells in calcium-containing or calcium-free buffers. The stimuli cause changes of the intracellular calcium ion concentration [Ca2+]i as well as the histamine. The [Ca2+]i increases when the frequency of the external electric field increases from 100 Hz to 10 kHz, and then decreases when the frequency further increases from 10 kHz to 100 kHz, showing a peak at 100 kHz. A similar frequency dependence of the histamine release is also found. The [Ca2+]i and the histamine releases at 100 Hz are about the same as the values of the control group with no electrical stimulation. The ruthenium red (RR), an inhibitor to the TRPV (transient receptor potential (TRP) family V) channels across the cell membrane, is used in the experiment to check whether the electric field stimuli act on the TRPV channels. Under an electric field of 10 kHz, the [Ca2+]i in a calcium-concentration buffer is about 3.5 times as much as that of the control group with no electric stimulation, while the [Ca2+]i in a calcium-free buffer is only about 2.2 times. Similar behavior is also found for the histamine release. RR blockage effect on the [Ca2+]i decrease is statistically significant (~75%) when mast cells in the buffer with calcium are stimulated with a 10 kHz electric field in comparison with the result without the RR treatment. This proves that TRPVs are the channels that calcium ions inflow through from the extracellular environment under electrical stimuli. Under this condition, the histamine is also released following a similar way. We suggest that, as far as an electric stimulation is concerned, an application of ac electric field of 10 kHz is better than other frequencies to open TRPV channels in mast cells, and this would cause a significant calcium influx resulting in a significant histamine release, which could be one of the mechanisms for electric therapy.

  18. Macelignan inhibits histamine release and inflammatory mediator production in activated rat basophilic leukemia mast cells.

    PubMed

    Han, Young Sun; Kim, Myung-Suk; Hwang, Jae-Kwan

    2012-10-01

    Type I allergy is characterized by the release of granule-associated mediators, lipid-derived substances, cytokines, and chemokines by activated mast cells. To evaluate the anti-allergic effects of macelignan isolated from Myristica fragrans Houtt., we determined its ability to inhibit calcium (Ca(2+)) influx, degranulation, and inflammatory mediator production in RBL-2 H3 cells stimulated with A23187 and phorbol 12-myristate 13-acetate. Macelignan inhibited Ca(2+) influx and the secretion of β-hexosaminidase, histamine, prostaglandin E(2), and leukotriene C(4); decreased mRNA levels of cyclooxygenase-2, 5-lipoxygenase, interleukin-4 (IL-4), IL-13, and tumor necrosis factor-α; and attenuated phosphorylation of Akt and the mitogen-activated protein kinases extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase. These results indicate the potential of macelignan as a type I allergy treatment.

  19. Ultramicronized palmitoylethanolamide reduces viscerovisceral hyperalgesia in a rat model of endometriosis plus ureteral calculosis: role of mast cells.

    PubMed

    Iuvone, Teresa; Affaitati, Giannapia; De Filippis, Daniele; Lopopolo, Mariangela; Grassia, Gianluca; Lapenna, Domenico; Negro, Luana; Costantini, Raffaele; Vaia, Massimo; Cipollone, Francesco; Ialenti, Armando; Giamberardino, Maria Adele

    2016-01-01

    The effects of ultramicronized palmitoylethanolamide were evaluated on pain behaviours and markers of mast cell (MC) activity in a rat model of endometriosis plus ureteral calculosis (ENDO+STONE)-induced viscerovisceral hyperalgesia (VVH). Female Sprague-Dawley rats that underwent surgical induction of endometriosis were randomly assigned to receive active (ultramicronized palmitoylethanolamide 10 mg·kg(-1)·d(-1), orally) or placebo treatment for 25 days. At day 21, they underwent ureteral stone formation and were video-recorded till day 25 to evaluate ureteral and uterine pain behaviours. At autopsy (day 25), ureteral condition and number and diameter of endometrial cysts were evaluated. The following were then measured: number and percentage of degranulating MCs, number of vessels, chymase, nerve growth factor (NGF), vascular endothelial growth factor (VEGF), and Flk-1 (VEGF receptor) in cysts, and NGF in dorsal root ganglia (DRG). Ultramicronized palmitoylethanolamide-treated vs placebo-treated rats showed significantly lower number, duration and complexity of ureteral crises, shorter duration of uterine pain, and smaller cyst diameter (0.0001 < P < 0.004); a significantly higher percentage of expelled stones (P < 0.0001); significantly lower MC number (P < 0.01), vessel number (P < 0.01), chymase (P < 0.05), NGF (P < 0.05), VEGF (P < 0.01), and Flk-1 (P < 0.01) expression in cysts and NGF expression in DRG (P < 0.01). In all animals, the global duration of ureteral crises correlated linearly and directly with cyst diameter, MC number and chymase in cysts, and NGF in cysts and DRG (0.02 < P < 0.0002). Ultramicronized palmitoylethanolamide significantly reduces VVH from ENDO+STONE, probably by modulating MC expression/activity in cysts, thus reducing central sensitization due to noxious signals from endometriotic lesions. The results suggest potential utility of the compound for VVH in clinics.

  20. Effect of royal jelly on experimental colitis induced by acetic acid and alteration of mast cell distribution in the colon of rats

    PubMed Central

    Karaca, T.; Bayiroglu, F.; Yoruk, M.; Kaya, M.S.; Uslu, S.; Comba, B.; Mis, L.

    2010-01-01

    This study investigated the effects of royal jelly (RJ) on acetic acid-induced colitis in rats. Twenty adult female Wistar albino rats were divided into four treatment groups of 5 animals each, including a control group (Group I); Group II was treated orally with RJ (150 mg kg−1 body weight); Group III had acetic acid-induced colitis; and Group IV had acetic acid-induced colitis treated orally with RJ (150 mg kg−1 body weight) for 4 weeks. Colitis was induced by intracolonic instillation of 4% acetic acid; the control group received physiological saline (10 mL kg−1). Colon samples were obtained under deep anaesthesia from animals in all groups. Tissues were fixed in 10% formalin neutral buffer solution for 24 h and embedded in paraffin. Six-micrometre-thick sections were stained with Mallory’s triple stain and toluidine blue in 1% aqueous solution at pH 1.0 for 5 min (for Mast Cells). RJ was shown to protect the colonic mucosa against the injurious effect of acetic acid. Colitis (colonic damage) was confirmed histomorphometrically as significant increases in the number of mast cells (MC) and colonic erosions in rats with acetic acid-induced colitis. The RJ treatment significantly decreased the number of MC and reduced the area of colonic erosion in the colon of RJ-treated rats compared with rats with untreated colitis. The results suggest that oral treatment with RJ could be used to treat colitis. PMID:21263740

  1. Number Density of Mast Cells in the Primo Nodes of Rats.

    PubMed

    Gil, HyunJi; Bae, Kyoung-Hee; Kim, LiJung; Kim, SungChul; Soh, Kwang-Sup

    2015-12-01

    Mast cells (MCs) play a major role in allergic reactions. Surprisingly, the acupuncture points have a higher density of MCs compared with nonacupoints in the skin, which is consistent with the augmentation of the immune function by acupuncture treatment. We hypothesized that the primo vascular system (PVS), which was proposed as the anatomical structure of the acupuncture points and meridians, should have a high density of MCs. In order to test that hypothesis, we investigated the primo nodes isolated from the surfaces of internal organs, such as the liver, the small and the large intestines, and the bladder. The harvested primo nodes were stained with toluidine blue, and the MCs were easily recognized by their red-purple stains and their characteristic granules. The results showed a high density of MCs in the primo nodes and confirmed the hypothesis. The MCs were uniformly distributed in the nodes. The relative concentration of the MCs with respect to other cells was ∼15%. We divided the sizes of the primo nodes into three classes: large, medium, and small. The number density and the relative concentration of MCs did not show a size-dependence. The current work suggests that the PVS may participate in the immune response to allergic inflammation, which closely involves MCs.

  2. Radiation-Released Histamine in the Rhesus Monkey as Modified by Mast Cell Depletion and Antihistamine

    DTIC Science & Technology

    1975-06-01

    radiation of two untreated monkeys, four monkeys given chlorpheniramine 30 minutes before irradiation and four monkeys treated with 48/80 for four...antagonist, chlorpheniramine ’ (3 mg/kg), 30 minutes before irradiation. Experiment 3. Seven monkeys were given aminoguanidine and 30 minutes later the...4000-rad dose of ionizing radiation in animals receiving no treatment. When the animals were pretreated with chlorpheniramine , the histamine

  3. Antimicrobial agent triclosan is a proton ionophore uncoupler of mitochondria in living rat and human mast cells and in primary human keratinocytes.

    PubMed

    Weatherly, Lisa M; Shim, Juyoung; Hashmi, Hina N; Kennedy, Rachel H; Hess, Samuel T; Gosse, Julie A

    2016-06-01

    Triclosan (TCS) is an antimicrobial used widely in hospitals and personal care products, at ~10 mm. Human skin efficiently absorbs TCS. Mast cells are ubiquitous key players both in physiological processes and in disease, including asthma, cancer and autism. We previously showed that non-cytotoxic levels of TCS inhibit degranulation, the release of histamine and other mediators, from rat basophilic leukemia mast cells (RBL-2H3), and in this study, we replicate this finding in human mast cells (HMC-1.2). Our investigation into the molecular mechanisms underlying this effect led to the discovery that TCS disrupts adenosine triphosphate (ATP) production in RBL-2H3 cells in glucose-free, galactose-containing media (95% confidence interval EC50 = 7.5-9.7 µm), without causing cytotoxicity. Using these same glucose-free conditions, 15 µm TCS dampens RBL-2H3 degranulation by 40%. The same ATP disruption was found with human HMC-1.2 cells (EC50 4.2-13.7 µm), NIH-3 T3 mouse fibroblasts (EC50 4.8-7.4 µm) and primary human keratinocytes (EC50 3.0-4.1 µm) all with no cytotoxicity. TCS increases oxygen consumption rate in RBL-2H3 cells. Known mitochondrial uncouplers (e.g., carbonyl cyanide 3-chlorophenylhydrazone) previously were found to inhibit mast cell function. TCS-methyl, which has a methyl group in place of the TCS ionizable proton, affects neither degranulation nor ATP production at non-cytotoxic doses. Thus, the effects of TCS on mast cell function are due to its proton ionophore structure. In addition, 5 µm TCS inhibits thapsigargin-stimulated degranulation of RBL-2H3 cells: further evidence that TCS disrupts mast cell signaling. Our data indicate that TCS is a mitochondrial uncoupler, and TCS may affect numerous cell types and functions via this mechanism. Copyright © 2015 John Wiley & Sons, Ltd.

  4. The outwardly rectifying chloride channel in rat peritoneal mast cells is regulated by serine/threonine kinases and phosphatases.

    PubMed

    Seebeck, Jörg; Tritschler, Stefan; Roloff, Tim; Kruse, Marie-Luise; Schmidt, Wolfgang E; Ziegler, Albrecht

    2002-02-01

    A slowly activating, outwardly rectifying Cl- channel (ORCC) has been described in rat peritoneal mast cells (RPMCs). This channel is activated by intracellular application of cAMP, an effect that might be mediated by a PKA-type serine/threonine protein kinase. To test this hypothesis, whole-cell patch-clamp experiments (nystatin-perforated patch) were performed and 8-bromoadenosine 3',5'-cyclic monophosphothioate, Sp-enantiomer (Sp-8Br-cAMPS), a cell membrane-permeable activator of PKA, and three inhibitors of different serine/threonine protein phosphatases (okadaic acid, cantharidin, calyculin A), were tested. In RPMCs application of repetitive series of step hyper- and depolarizations (holding potential 0 mV, test potentials -80 to +80 mV, step size +20 mV) induced a slowly increasing, [half-maximal activation time ( t0.5) 11.0+/-1.1 min, Imax (at +80 mV) 18.7+/-3.1 pA pF-1], DIDS-sensitive, outwardly rectifying Cl- current I(Cl,OR). The activation of this current could be accelerated by Sp-8Br-cAMPS, okadaic acid or cantharidin in the extracellular solution. Co-application of Sp-8Br-cAMPS and okadaic acid increased Imax supra-additively. Calyculin A and higher concentrations of cantharidin inhibited the Cl- current via unknown mechanisms. Our findings suggest that I(Cl,OR) in RPMCs is activated by a PKA-type protein kinase, a process which is antagonized functionally by okadaic acid- and cantharidin-sensitive protein phosphatases.

  5. Effects of methyl p-hydroxybenzoate (methyl paraben) on Ca2+ concentration and histamine release in rat peritoneal mast cells

    PubMed Central

    Fukugasako, Sanae; Ito, Shinichi; Ikemoto, Yoshimi

    2003-01-01

    Mechanisms of methyl p-hydroxybenzoate (methyl paraben) action in allergic reactions were investigated by measuring the intracellular Ca2+ concentration ([Ca2+]i) and histamine release in rat peritoneal mast cells (RPMCs). In the presence or absence of extracellular Ca2+, methyl paraben (0.1–10 mM) increased [Ca2+]i, in a concentration-dependent manner. Under both the conditions, methyl paraben alone did not evoke histamine release. In RPMCs pretreated with a protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate (PMA) 3 and 10 nM), methyl paraben (0.3–3 mM) induced histamine release. However, a high concentration (10 mM) of the agent did not increase the histamine release. U73122 (0.1 and 0.5 μM), an inhibitor of phospholipase C (PLC), significantly inhibited the methyl paraben-induced histamine release in PMA-pretreated RPMCs. U73343 (0.5 μM), an inactive analogue of U73122, did not inhibit the histamine release caused by methyl paraben. In Ca2+-free solution, PLC inhibitors (U73122 0.1 and 0.5 μM, D609 1–10 μM) inhibited the methyl paraben-induced increase in [Ca2+]i, whereas U73343 (0.5 μM) did not. Xestospongin C (2–20 μM) and 2 aminoethoxydiphenyl borate (30 and 100 μM), blockers of the inositol 1,4,5-trisphosphate (IP3) receptor, inhibited the methyl paraben-induced increase in [Ca2+]i in Ca2+-free solution. In conclusion, methyl paraben causes an increase in [Ca2+]i, which may be due to release of Ca2+ from storage sites by IP3 via activation of PLC in RPMCs. In addition, methyl paraben possibly has some inhibitory effects on histamine release via unknown mechanisms. PMID:12770943

  6. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle.

    PubMed

    McCarthy, John J; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B; Srikuea, Ratchakrit; Lawson, Benjamin A; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S; Esser, Karyn A; Dupont-Versteegden, Esther E; Peterson, Charlotte A

    2011-09-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca(2+) sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells.

  7. Characterization of the choroidal mast cell.

    PubMed Central

    Godfrey, W A

    1987-01-01

    The experimental studies performed on nonpigmented rat choroids and the review of the important literature covered in this thesis seem to justify the following statements: 1. Mast cells are present in the choroid in significant numbers. 2. Mast cell numbers vary considerably from one individual to another and from one location in the choroid to another. 3. The major concentration of mast cells in the uvea is in the posterior choroid. 4. The mast cells of the choroid have a preferential location along arterial vessels. 5. Choroidal mast cell population density apparently decreases with senescence. 6. Mast cell products are present in sufficient quantity to exert substantial effects on physiologic, immunologic, and inflammatory responses in the choroid. 7. Choroidal mast cell products are released with appropriate stimulation and share some properties with the connective-tissue mast cell. 8. Choroidal mast cell demonstrate enough differences to suggest that a local differentiation may be present and may represent a locally controlled modulating effect for choroidal physiologic, immunologic, and inflammatory reactions. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 15 FIGURE 16 FIGURE 17 PMID:3328921

  8. Rotational dynamics of type I Fc epsilon receptors on individually-selected rat mast cells studied by polarized fluorescence depletion.

    PubMed Central

    Rahman, N A; Pecht, I; Roess, D A; Barisas, B G

    1992-01-01

    We report the first application of polarized fluorescence depletion (PFD), a technique which combines the sensitivity of fluorescence detection with the long lifetimes of triplet probes, to the measurement of membrane protein rotational diffusion on individually selected, intact mammalian cells. We have examined the rotation of type I Fc epsilon receptors (Fc epsilon RI) on rat mucosal mast cells of the RBL-2H3 line in their resting monomeric and differently oligomerized states using as probes IgE and three monoclonal antibodies (mAbs; H10, J17, and F4) specific for the Fc epsilon RI. PFD experiments using eosin (EITC)-IgE show that individual Fc epsilon RI on cells have a rotational correlation time (RCT) at 4 degrees C of 79 +/- 4 microseconds. Similarly, Fc epsilon RI-bound EITC-Fab fragments of the J17 Fc epsilon RI-specific mAb exhibit an RCT of 76 +/- 6 microseconds. These values agree with previous measurements of Fc epsilon RI-bound IgE rotation by time-resolved phosphorescence anisotropy methods. Receptor-bound EITC-conjugated divalent J17 antibody exhibits an increased RCT of 140 +/- 6 microseconds. This is consistent with the ability of this mAb to form substantial amounts of Fc epsilon RI dimers on these cell surfaces. The ratio of limiting to initial anisotropy in these experiments remains constant at about 0.5 from 5 degrees C through 25 degrees C for IgE, Fab, and intact mAb receptor ligands. Extensive cross-linking by second antibody of cell-bound IgE, of intact Fc epsilon RI-specific mAbs or of their Fab fragments, however, produced large fixed anisotropies demonstrating, under these conditions, receptor immobilization in large aggregates. PFD using the mAbs H10 and F4 as receptor probes yielded values for triplet lifetimes, RCT values, and anisotropy parameters essentially indistinguishable from those obtained with the mAb J17 clone. Possible explanations for these observations are discussed. PMID:1547323

  9. Inflammatory oedema induced by phospholipases A2 isolated from Crotalus durissus sp. in the rat dorsal skin: a role for mast cells and sensory C-fibers.

    PubMed

    Câmara, Paula R S; Esquisatto, Laura C M; Camargo, Enilton A; Ribela, Maria Teresa C P; Toyama, Marcos H; Marangoni, Sergio; De Nucci, Gilberto; Antunes, Edson

    2003-06-01

    The ability of the phospholipases A(2) (PLA(2)s) from Crotalus durissus cascavella, Crotalus durissus collilineatus and Crotalus durissus terrificus venoms and crotapotin to increase the vascular permeability in the rat skin as well as the contribution of both mast cells and sensory C-fibers have been investigated in this study. Vascular permeability was measured as the plasma extravascular accumulation at skin sites of intravenously injected 125I-human serum albumin. Intradermal injection of crotalic PLA(2)s (0.05-0.5 microg/site) in the rat skin resulted in dose-dependent increase in plasma extravascular whereas crotapotin (1 microg/site) failed to affect this response. Co-injection of crotapotin (1 microg/site) did not modify the increased vascular permeability induced by the PLA(2)s (0.05-0.5 microg/site). Previous treatment (30 min) of the animals with cyproheptadine (2 mg/kg, i.p.) markedly reduced PLA(2) (0.5 microg/site)-induced oedema. In rats treated neonatally with capsaicin to deplete neuropeptides, the plasma extravasation induced by all PLA(2)s (0.5 microg/site) was also significantly reduced. Similarly, the tachykinin NK(1) receptor antagonist SR140333 (1nmol/site) significantly reduced the PLA(2)-induced oedema. In addition, the combination of SR140333 with cyproheptadine further reduced the increased plasma extravasation by PLA(2) from C. d. cascavella venom, but not by PLA(2) from C. d. terrificus and C. d. collilineatus venoms. Our results suggest that increase in skin vascular permeability by crotalic PLA(2)s is mediated by activation of sensory C-fibers culminating in the release of substance P, as well as by activation of mast cells which in turn release amines such as histamine and serotonin.

  10. Pretreatment with Evans blue, a stimulator of BK(Ca) channels, inhibits compound 48/80-induced shock, systemic inflammation, and mast cell degranulation in the rat.

    PubMed

    Fu, Yaw-Syan; Kuo, Su-Yu; Lin, Hsuan-Yea; Chen, Chun-Lin; Huang, Shi-Ying; Wen, Zhi-Hong; Lee, Kun-Zer; Huang, Hung-Tu

    2015-09-01

    The present study demonstrated that intravenous injection of a high dose of compound 48/80 to the rat induced 50% drop, within a few min, in the mean arterial pressure and pulse pressure as well as systemic inflammatory plasma leakage that might lead to circulatory and respiratory failure. We also investigated whether pretreatment with Evans blue, a stimulator of BK(Ca) channels, could exert inhibitory effect against compound C48/80-induced allergic circulatory shock and systemic inflammation. Different groups of Sprague-Dawley rats received an intravenous injection of a dose of Evans blue (0, 5, 10, or 50 mg/kg) just 20 s prior to injection of compound 48/80 (200 μg/kg, over 2 min). The present study found that pretreatment with Evans blue in a dose of 10 or 50 mg/kg exerted acute inhibitory effect on compound 48/80-induced sudden drop in mean arterial and pulse pressures. We also showed that pretreatment with Evans blue in a dose of 5, 10, or 50 mg/kg significantly inhibited compound 48/80-induced extensive plasma extravasation, mast cell degranulation, and edema formation in various organs including the airways, esophagus, and skin. Pretreatment with Evans blue 50 mg/kg 1 h earlier exhibited longer-term inhibitory effect on compound 48/80-induced arterial hypotension and systemic inflammation. We concluded that Evans blue pretreatment prevented rats from compound 48/80-triggered allergic shock and systemic inflammation, possibly mainly through inhibition of mast cell degranulation. Evans blue might be potentially useful in elucidating the mechanism and acting as a therapeutic agent of allergic shock and systemic inflammation.

  11. Activation of the Na+/K(+)-pump in rat peritoneal mast cells following histamine release: a possible role in cell recovery.

    PubMed Central

    Knudsen, T.; Ferjan, I.; Johansen, T.

    1993-01-01

    1. The activity of the Na+/K(+)-pump in rat peritoneal mast cells was measured at various time intervals after induction of cellular histamine release by compound 48/80 or by the antigen-antibody reaction. The Na+/K(+)-pump activity was assessed as the ouabain-sensitive potassium uptake of the cells using 86Rb+ as a tracer for potassium (K+(86Rb+)-uptake). 2. Stimulation of the cells with compound 48/80 induced a time and concentration dependent increase of the Na+/K(+)-pump activity. The pump activity was maximal 2 min after stimulation of the cells. Then, the activity gradually decreased and reached a level not significantly different from the controls after 2 h of incubation. 3. When the cells were stimulated by the antigen-antibody reaction, there was also a rapid (within 5 min) stimulation of the Na+/K(+)-pump. In contrast to the stimulation with compound 48/80, the pump activity returned to the control level after 60 min of incubation with antigen. 4. The ouabain-resistant potassium uptake of the cells was increased after stimulation of the cells, regardless of the secretagogue used. This probably reflects the increased surface area of the cells present after the histamine release. 5. On the basis of the present results, we suggest a role for the Na+/K(+)-pump in the recovery process of the mast cell following histamine release. PMID:7679025

  12. Cytoskeletal studies on Lowicryl K4M embedded and Affi-Gel 731 attached rat peritoneal mast cells.

    PubMed

    Nielsen, E H; Jahn, H

    1984-01-01

    The subplasmalemmal network in mast cells consists of irregularly arranged 6-7 nm filaments (actin) connected by thinner filaments. In places oblique filaments with crossbridges or short, perpendicular filaments (11-12 nm) connect cell and granule membrane. Filaments attaching subplasmalemmal network to cell membrane divide like a Y and attach cell membrane end-on with a conical, hook-like bending. Each granule is surrounded by a regular network of filaments.

  13. Laser photobiomodulation (830 and 660 nm) in mast cells, VEGF, FGF, and CD34 of the musculocutaneous flap in rats submitted to nicotine.

    PubMed

    das Neves, Lais Mara Siqueira; Leite, Gabriella de Paula Marcondes Ferreira; Marcolino, Alexandre Marcio; Pinfildi, Carlos Eduardo; Garcia, Sérgio Britto; de Araújo, João Eduardo; Guirro, Elaine Caldeira de Oliveira

    2017-02-01

    The aim of this study was to investigate the effect of laser photobiomodulation (PBM) on the viability of the transverse rectus abdominis musculocutaneous (TRAM) flap in rats subjected to the action of nicotine. We evaluated 60 albino Wistar rats, divided into six groups of ten animals. Group 1 (saline) underwent the surgical technique to obtain a TRAM flap; group 2 (laser 830 nm) underwent the surgical technique and was irradiated with a laser 830 nm; group 3 (laser 660 nm) underwent the surgical technique and was irradiated with a laser 660 nm; group 4 was treated with nicotine subcutaneously (2 mg/kg/2×/day/4 weeks) and underwent surgery; group 5 (nicotine + laser 830 nm) was exposed to nicotine, underwent the surgical technique, and was irradiated with a laser 830 nm; group 6 (nicotine + laser 660 nm) was exposed to nicotine, underwent the surgical technique, and was irradiated with a laser 660 nm. The application of PBM occurred immediately after surgery and on the two following days. The percentage of necrosis was assessed using the AxioVision® software. The number of mast cells (toluidine blue staining) was evaluated, and immunohistochemistry was performed to detect vascular endothelial growth factor expression (anti-VEGF-A), fibroblasts (anti-basic FGF), and neoformed vessels (anti-CD34). PBM with a wavelength of 830 nm increased the viability of the TRAM flap, with a smaller area of necrosis, increased number of mast cells, and higher expression of VEGF and CD34. PBM increases the viability of musculocutaneous flaps treated with to nicotine.

  14. Effects of mucoid and non-mucoid Pseudomonas aeruginosa isolates from cystic fibrosis patients on inflammatory mediator release from human polymorphonuclear granulocytes and rat mast cells.

    PubMed Central

    Friedl, P; König, B; König, W

    1992-01-01

    Mucoid Pseudomonas aeruginosa causing chronic bronchopulmonary infection in cystic fibrosis (CF) patients may interfere with host defence mechanisms. We investigated 13 P. aeruginosa strains isolated from sputa of CF patients with regard to the induction or modulation of inflammatory mediator release from human neutrophils (PMN) and rat mast cells. The effects of mucoid as compared to non-mucoid bacteria were studied using a mucoid strain and its non-mucoid revertant. The release of leukotrienes (LT) and histamine in response to the majority of the CF strains was insignificant. However, preincubation of PMN with P. aeruginosa caused a dose-dependent decrease (50-95%) of LTB4 and LTC4 generation and LTB4 metabolism induced by the Ca(2+)-ionophore A23187 or opsonized zymosan (ZX) (P less than 0.001). The mucoid strains caused a three- to 10-fold higher impairment of LTB4 release (P less than 0.05) and a concomitant down-regulation of LTB4 receptors on neutrophils. Inhibitory effects were also obtained for mucoid and non-mucoid bacteria when the phorbol-ester or the Ca(2+)-ionophore induced luminol enhanced chemiluminescence response (P less than 0.001) or the histamine release from rat peritoneal mast cells (P less than 0.01) was studied. The bacteria-cell contact with non-mucoid strains was associated with an increased Ca2+ influx into PMN, whereas mucoid bacteria had no effect. In addition, a protein kinase C-dependent decrease of the C3bi receptor was suppressed by the mucoid--and less effectively--by the non-mucoid strain. The results suggest that the impairment of the phagocytic and inflammatory system may contribute to the pathogenesis and persistence of mucoid P. aeruginosa infection in CF. PMID:1321094

  15. Early Phase Mast Cell Activation Determines the Chronic Outcome of Renal Ischemia-Reperfusion Injury.

    PubMed

    Danelli, Luca; Madjene, Lydia Celia; Madera-Salcedo, Iris; Gautier, Gregory; Pacreau, Emeline; Ben Mkaddem, Sanae; Charles, Nicolas; Daugas, Eric; Launay, Pierre; Blank, Ulrich

    2017-03-15

    Ischemia-reperfusion injury (IRI) is an important cause of acute kidney injury that can lead to end-stage renal failure. Although the ensuing inflammatory response can restore homeostasis, a consecutive maladaptive repair and persistent inflammation represent important risk factors for postischemic chronic kidney disease development. In this study, we investigated the role of mast cells in both the early and late phases of the inflammatory response in experimental models of acute and chronic renal IRI using our recently developed mouse model that allows conditional ablation of mast cells. Depletion of mast cells prior to IRI resulted in improved renal function due to diminished local inflammatory cytokine/chemokine levels and neutrophil recruitment to the kidneys after the acute injury phase (48 h post-IRI). Furthermore, although not completely protected, mast cell-depleted mice displayed less organ atrophy and fibrosis than did wild-type mice during the chronic phases (2 and 6 wk post-IRI) of disease development. Conversely, mast cell ablation after the acute phase of IRI had no impact on organ atrophy, tubular necrosis, or fibrosis. Thus, our results suggest a deleterious role of mast cells during the acute inflammatory phase of IRI promoting subsequent fibrosis development, but not during the chronic phase of the disease.

  16. B cell depletion for autoimmune diseases in paediatric patients.

    PubMed

    Jansson, Annette F; Sengler, Claudia; Kuemmerle-Deschner, Jasmin; Gruhn, Bernd; Kranz, A Birgitta; Lehmann, Hartwig; Kleinert, Daniela; Pape, Lars; Girschick, Hermann J; Foeldvari, Ivan; Haffner, Dieter; Haas, Johannes P; Moebius, Dagmar; Foell, Dirk; Peitz, Joachim; Grote, Veit

    2011-01-01

    Data on B cell depletion therapy in severe autoimmune diseases in paediatric patients are very limited. We conducted a retrospective cohort study and recruited patients who were treated with rituximab (RTX) and followed up for at least 6 months through the German societies of paediatric rheumatology and nephrology. The aim was to describe the spectrum of autoimmune disorders for which RTX was used and to describe the applied therapeutic regimens, the observed efficacy, as well as potential immunological side effects. The need to develop standard treatment guidelines for future trials should be discussed. Sixty-five patients were included. Nineteen patients suffered from systemic lupus erythematosus, 13 from vasculitic disorders, 12 from hematological autoimmune diseases, 5 from mixed connective tissue disorders, 4 from juvenile idiopathic arthritis, and 9 had other autoimmune diseases. Adverse, infusion-related events were reported in 12/65 (18%) patients. Considering laboratory and clinical parameters, 13 patients (22%) were in complete remission, 31 (52%) were in partial remission, 6 (10%) were unchanged and 10 (17%) had progressed after 6 months. In 46% of the patients, the steroid dose could be more than halved. IgG, IgM and IgA decreased from normal levels prior to RTX therapy to below normal levels at 6 months in 2/22 (9%), 10/21 (48%), and 4/22 (18%) patients, respectively. Immunoglobulin deficiency or prolonged CD20 depletion was reported in eight patients after an observation period longer than 12 months. RTX therapy led to a perceivable reduction in disease activity. However, long-term immunological alterations may occur in more than 10% of the patients. Guidelines and protocols for off-label therapy are desirable to document reasonable follow-up data. Controlled prospective studies for RTX therapies in children with standardised therapeutic and diagnostic protocols are urgently needed.

  17. 46. BASE OF UMBILICAL MAST FROM UMBILICAL MAST TRENCH. ERECTION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. BASE OF UMBILICAL MAST FROM UMBILICAL MAST TRENCH. ERECTION AND RETRACTION CYLINDERS BETWEEN MAST AND TRENCH WALL. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. Pulmonary neutrophil recruitment and bronchial reactivity in formaldehyde-exposed rats are modulated by mast cells and differentially by neuropeptides and nitric oxide

    SciTech Connect

    Lino dos Santos Franco, Adriana; Damazo, Amilcar Sabino; Beraldo de Souza, Hyula Regines; Domingos, Helory Vanni; Oliveira-Filho, Ricardo Martins; Oliani, Sonia Maria; Costa, Soraia Katia Pereira; Tavares de Lima, Wothan . E-mail: wtdelima@icb.usp.br

    2006-07-01

    We have used a pharmacological approach to study the mechanisms underlying the rat lung injury and the airway reactivity changes induced by inhalation of formaldehyde (FA) (1% formalin solution, 90 min once a day, 4 days). The reactivity of isolated tracheae and intrapulmonary bronchi were assessed in dose-response curves to methacholine (MCh). Local and systemic inflammatory phenomena were evaluated in terms of leukocyte countings in bronchoalveolar lavage (BAL) fluid, blood, bone marrow lavage and spleen. Whereas the tracheal reactivity to MCh did not change, a significant bronchial hyporesponsiveness (BHR) was found after FA inhalation as compared with naive rats. Also, FA exposure significantly increased the total cell numbers in BAL, in peripheral blood and in the spleen, but did not modify the counts in bone marrow. Capsaicin hindered the increase of leukocyte number recovered in BAL fluid after FA exposure. Both compound 48/80 and indomethacin were able to prevent the lung neutrophil influx after FA, but indomethacin had no effect on that of mononuclear cells. Following FA inhalation, the treatment with sodium cromoglycate (SCG), but not with the nitric oxide (NO) synthase inhibitor L-NAME, significantly reduced the total cell number in BAL. Compound 48/80, L-NAME and SCG significantly prevented BHR to MCh after FA inhalation, whereas capsaicin was inactive in this regard. On the other hand, indomethacin exacerbated BHR. These data suggest that after FA inhalation, the resulting lung leukocyte influx and BHR may involve nitric oxide, airway sensory fibers and mast cell-derived mediators. The effect of NO seemed to be largely restricted to the bronchial tonus, whereas neuropeptides appeared to be linked to the inflammatory response, therefore indicating that the mechanisms responsible for the changes of airway responsiveness caused by FA may be separate from those underlying its inflammatory lung effects.

  19. Mast Cell Function

    PubMed Central

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

  20. Mast cells and inflammation.

    PubMed

    Frenzel, Laurent; Hermine, Olivier

    2013-03-01

    The prominent role for mast cells in the inflammatory response has been increasingly well documented in recent years. Mast cells not only contribute to maintain homeostasis via degranulation and to generate IgE-mediated allergic reactions, but also sit at a major crossroads for both innate and adaptive immune responses. The part played by mast cells in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis identifies mast cells as a valuable treatment target in these diseases. Tyrosine-kinase inhibitors targeting the c-Kit mast cell receptor have been found effective in treating rheumatoid arthritis, asthma, and multiple sclerosis. When used in combination with other available drugs, tyrosine-kinase inhibitors may improve the therapeutic management of these diseases.

  1. Combined exposure of peripubertal male rats to the endocrine-disrupting compound atrazine and power-frequency electromagnetic fields causes degranulation of cutaneous mast cells: a new toxic environmental hazard?

    PubMed

    Rajkovic, Vesna; Matavulj, Milica; Johansson, Olle

    2010-08-01

    The effects of single and combined treatments of the endocrine-disrupting compound atrazine and the power-frequency electromagnetic fields (EMFs) were investigated on cutaneous mast cells in juvenile/peripubertal male Wistar rats. Animals were divided into six groups: (1) 4 h/day exposure to EMFs (50 Hz), (2) 20 mg/kg of body weight (bw) of atrazine, (3) 200 mg/kg bw of atrazine, (4) EMFs with 20 mg/kg bw of atrazine, (5) EMFs with 200 mg/kg bw of atrazine, and (6) control. Both the atrazine and the combined treatments, but not the single EMF exposure, increased the number of degranulated mast cells. Statistically significant differences were demonstrated between the control and both of the combined treatments (p<0.01 and p<0.001, respectively). Additionally, low and high doses of atrazine combined with the EMFs were found significantly different when compared to the EMF group alone (both at p<0.001). Considering the biological importance of mast cells in cutaneous immune reactions, future studies should reveal whether combined exposures to chemical and physical environmental agents pose a serious health risk.

  2. The exocytotic signaling pathway induced by nerve growth factor in the presence of lyso-phosphatidylserine in rat peritoneal mast cells involves a type D phospholipase.

    PubMed

    Seebeck, J; Westenberger, K; Elgeti, T; Ziegler, A; Schütze, S

    2001-12-15

    Nerve growth factor (NGF) has been previously shown to induce exocytosis in rat peritoneal mast cells (RPMCs) in the presence of lyso-phosphatidylserine (lysoPS) by interacting with high-affinity NGF receptors of the TrkA-type. In RPMCs, type D phosphatidylcholine-selective phospholipases (PLDs) have been postulated to be involved in some exocytotic signaling pathways induced by different agonists. The aim of the present study was to assess a putative functional role of PLD for NGF/lysoPS-induced exocytosis in RPMCs. In 1-[14C]palmitoyl-2-lyso-3-phosphatidylcholine-labelled RPMCs, NGF/lysoPS stimulated the formation of diacylglycerol (DAG) and, in the presence of ethanol (1% [v/v]), phosphatidylethanol (PEtOH). These data indicate PLD-activation by NGF/lysoPS in RPMCs. Preincubation of RPMCs for 2 min with ethanol, an inhibitor of PLD-derived DAG-formation, dose-dependently (IC(50): 0.6% [v/v]) and agonist-selectively inhibited the NGF/lysoPS induced release of [3H]serotonin ([3H]5-HT) in [3H]5-HT-loaded RPMCs, confirming the functional importance of PLD-action. Exocytosis and PEtOH-production was potently inhibited by the broad-spectrum serine/threonine kinase inhibitor staurosporine and activated by the protein kinase C(PKC)-activator PMA (phorbol-12-myristate-13-acetate) suggesting a role for PKC as mediator for NGF/lysoPS-induced activation of PLD.

  3. Mast cells and inflammation.

    PubMed

    Stassen, Michael; Hültner, Lothar; Müller, Christian; Schmitt, Edgar

    2002-01-01

    Mast cells have long been recognized as potent producers of a large panel of biologically highly active mediators such as biogenic amines, arachidonic acid metabolites, cytokines and chemokines, but most of their biological functions have been elusive and speculative. By taking advantage of mast cell-deficient mice, the role of mast cells in a variety of experimental settings can now be studied in detail and such approaches have dramatically altered and enlarged our knowledge about mast cell biology and function. Herein we will focus on the role of mast cells in inflammatory reactions of diverse origin, such as delayed type hypersensitivity, atopy, immune complex-mediated inflammation and innate immune responses. From the current standpoint, there is no doubt that the most outstanding and beneficial feature of mast cells is their recently discovered ability to induce a life-saving inflammatory response rapidly upon encountering microbes and microbial constituents. Nevertheless, the picture is also emerging that mast cells are deeply involved in the induction and maintenance of a variety of severe allergic and autoimmune diseases. However, a deeper understanding of their activation and immune-modulatory capacity might open a new window for the development of curative strategies.

  4. IL-7 receptor blockade following T cell depletion promotes long-term allograft survival

    PubMed Central

    Mai, Hoa-Le; Boeffard, Françoise; Longis, Julie; Danger, Richard; Martinet, Bernard; Haspot, Fabienne; Vanhove, Bernard; Brouard, Sophie; Soulillou, Jean-Paul

    2014-01-01

    T cell depletion is commonly used in organ transplantation for immunosuppression; however, a restoration of T cell homeostasis following depletion leads to increased memory T cells, which may promote transplant rejection. The cytokine IL-7 is important for controlling lymphopoiesis under both normal and lymphopenic conditions. Here, we investigated whether blocking IL-7 signaling with a mAb that targets IL-7 receptor α (IL-7Rα) alone or following T cell depletion confers an advantage for allograft survival in murine transplant models. We found that IL-7R blockade alone induced indefinite pancreatic islet allograft survival if anti–IL-7R treatment was started 3 weeks before graft. IL-7R blockade following anti-CD4– and anti-CD8–mediated T cell depletion markedly prolonged skin allograft survival. Furthermore, IL-7 inhibition in combination with T cell depletion synergized with either CTLA-4Ig administration or suboptimal doses of tacrolimus to induce long-term skin graft acceptance in this stringent transplant model. Together, these therapies inhibited T cell reconstitution, decreased memory T cell numbers, increased the relative frequency of Tregs, and abrogated both cellular and humoral alloimmune responses. Our data suggest that IL-7R blockade following T cell depletion has potential as a robust, immunosuppressive therapy in transplantation. PMID:24569454

  5. Cumulative Doses of T-Cell Depleting Antibody and Cancer Risk after Kidney Transplantation.

    PubMed

    Chen, Jenny H C; Wong, Germaine; Chapman, Jeremy R; Lim, Wai H

    2015-01-01

    T-cell depleting antibody is associated with an increased risk of cancer after kidney transplantation, but a dose-dependent relationship has not been established. This study aimed to determine the association between cumulative doses of T-cell depleting antibody and the risk of cancer after kidney transplantation. Using data from the Australian and New Zealand Dialysis and Transplant Registry between 1997-2012, we assessed the risk of incident cancer and cumulative doses of T-cell depleting antibody using adjusted Cox regression models. Of the 503 kidney transplant recipients with 2835 person-years of follow-up, 276 (55%), 209 (41%) and 18 (4%) patients received T-cell depleting antibody for induction, rejection or induction and rejection respectively. The overall cancer incidence rate was 1,118 cancers per 100,000 patient-years, with 975, 1093 and 1377 cancers per 100,000 patient-years among those who had received 1-5 doses, 6-10 doses and >10 doses, respectively. There was no association between cumulative doses of T cell depleting antibody and risk of incident cancer (1-5: referent, 6-10: adjusted hazard ratio (HR) 1.19, 95%CI 0.48-2.95, >10: HR 1.42, 95%CI 0.50-4.02, p = 0.801). This lack of association is contradictory to our hypothesis and is likely attributed to the low event rates resulting in insufficient power to detect significant differences.

  6. Mast Cells: A Pivotal Role in Pulmonary Fibrosis

    PubMed Central

    Veerappan, Arul; O'Connor, Nathan J.; Brazin, Jacqueline; Reid, Alicia C.; Jung, Albert; McGee, David; Summers, Barbara; Branch-Elliman, Dascher; Stiles, Brendon; Worgall, Stefan; Kaner, Robert J.

    2013-01-01

    Pulmonary fibrosis is characterized by an inflammatory response that includes macrophages, neutrophils, lymphocytes, and mast cells. The purpose of this study was to evaluate whether mast cells play a role in initiating pulmonary fibrosis. Pulmonary fibrosis was induced with bleomycin in mast-cell-deficient WBB6F1-W/Wv (MCD) mice and their congenic controls (WBB6F1-+/+). Mast cell deficiency protected against bleomycin-induced pulmonary fibrosis, but protection was reversed with the re-introduction of mast cells to the lungs of MCD mice. Two mast cell mediators were identified as fibrogenic: histamine and renin, via angiotensin (ANG II). Both human and rat lung fibroblasts express the histamine H1 and ANG II AT1 receptor subtypes and when activated, they promote proliferation, transforming growth factor β1 secretion, and collagen synthesis. Mast cells appear to be critical to pulmonary fibrosis. Therapeutic blockade of mast cell degranulation and/or histamine and ANG II receptors should attenuate pulmonary fibrosis. PMID:23570576

  7. Optimising B-cell depletion in autoimmune disease: is obinutuzumab the answer?

    PubMed

    Reddy, Venkat; Dahal, Lekh N; Cragg, Mark S; Leandro, Maria

    2016-08-01

    In Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE), B-cell depletion therapy using rituximab results in variable clinical responses between individuals, which likely relates to variable B-cell depletion in the presence of immune defects. Outcomes in clinical trials with other type I anti-CD20 mAbs, ocrelizumab and ofatumumab, are comparable to rituximab. A mechanistically different type II mAb, obinutuzumab (OBZ), with greater capacity for B-cell depletion, has recently entered clinical trials in SLE. Here we consider whether type II anti-CD20 mAbs will provide mechanistic advantages to overcome the disease-related immune defects in autoimmune diseases such as SLE.

  8. Mucosal mast cells and developmental changes in gastric absorption.

    PubMed

    Catto-Smith, A G; Ripper, J L

    1995-01-01

    We aimed to establish whether gastric mucosal mast cells undergo degranulation during normal postnatal development and to correlate this with gastric electrical parameters, paracellular permeability, and macromolecular absorption. Sprague-Dawley rats were studied between 10 and 30 days after birth. Gastric mucosal mast cell degranulation occurred and was maximal on days 15 and 17, measured by histology and gastric and serum levels of rat mast cell protease II. Short-circuit current, transepithelial conductance, and permeability of voltage-clamped glandular stomach were elevated in younger animals, falling with age except for a transient but significant increase in conductance and permeability at 17 days, closely correlated with maximal mast cell degranulation. Macromolecular uptake was significantly increased in animals aged 10-15 days. Concanavalin A and antigen-induced mast cell degranulation increased conductance and permeability in vitro in younger animals. We conclude that 1) gastric mucosal mast cells degranulate during development, 2) the neonatal stomach has increased permeability and uptake of macromolecules, and 3) gastric mucosal mast cell degranulation during development may affect mucosal permeability.

  9. Growth of Mycobacterium marinum in the footpads of T-cell-depleted mice.

    PubMed

    Collins, F M; Montalbine, V; Morrison, N E

    1975-05-01

    Mycobacterium marinum strains 1218 and 1219 were inoculated into the hind footpads of T-cell-depleted specific pathogen-free C57B1/6 mice, and the growth and survival of the organisms at the site of injection, the draining popliteal lymph node, and the spleen and lung were quantitated for up to 70 days. T-cell depletion largely ablated the normal cell-mediated antituberculous response to the M. marinum population. The mice were able to control the further growth of the inoculum within the footpad only after it had reached 5 to 10 times that present in the normal controls. The high temperature-adapted strain (37 C; strain no. 1218) induced an increasing infection in the liver, spleen, and lungs of the THXB mice, and the infection eventually spread to the opposite footpad and to the tail skin. Strain 1219 gave rise to considerable systemic involvement in the THXB host despite its inability to survive at 37 C, but the size of the splenic and lung populations was considerably lower than in the 1218-infected animals. Both M. marinum infections persisted in the tissues of the T-cell-depleted mice with no indication of a cell-mediated immune response. Footpad swelling in the M. marinum-infected mice was not greatly reduced by T-cell depletion, and, if anything, tended to persist at high levels long after the swelling of the control feet had gone into a decline. On the other hand, incorporation of tritiated thymidine by cells within the infected footpads, the draining lymph node, and the spleen was considerably reduced in the T-cell-depleted host compared with control values. Late in the infection, there was a significant increase in the amount of label taken up by the cells in the footpads of the T-cell-depleted host.

  10. 45. VIEW OF UMBILICAL MAST TRENCH FROM BASE OF MAST, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. VIEW OF UMBILICAL MAST TRENCH FROM BASE OF MAST, FROM SOUTH. ACTUATORS FOR MAST TRENCH DOORS VISIBLE CONNECTING DOORS AND WALL. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  11. Mast cells and mastocytosis

    PubMed Central

    2008-01-01

    Mast cells have been recognized for well over 100 years. With time, human mast cells have been documented to originate from CD34+ cells, and have been implicated in host responses in both innate and acquired immunity. In clinical immunology, they are recognized for their central role in IgE-mediated degranulation and allergic inflammation by virtue of their expression of the high-affinity receptor for IgE and release of potent proinflammatory mediators. In hematology, the clinical disease of mastocytosis is characterized by a pathologic increase of mast cells in tissues, often associated with mutations in KIT, the receptor for stem cell factor. More recently, and with increased understanding of how human mast cells are activated through receptors including the high-affinity receptor for IgE and KIT, specific tyrosine kinase inhibitors have been identified with the potential to interrupt signaling pathways and thus limit the proliferation of mast cells as well as their activation through immunoglobulin receptors. PMID:18684881

  12. Mast Cell and Autoimmune Diseases

    PubMed Central

    Xu, Yunzhi; Chen, Guangjie

    2015-01-01

    Mast cells are important in innate immune system. They have been appreciated as potent contributors to allergic reaction. However, increasing evidence implicates the important role of mast cells in autoimmune disease like rheumatoid arthritis and multiple sclerosis. Here we review the current stage of knowledge about mast cells in autoimmune diseases. PMID:25944979

  13. Changes in levels of plasminogen activator activity in normal and germ-cell-depleted testes during development.

    PubMed

    Lacroix, M; Smith, F E; Fritz, I B

    1982-05-01

    Levels of plasminogen activator activity were determined in testes obtained from normal and irradiated rats in various ages. During normal development, plasminogen activator activity per g testis increased rapidly between 40 and 60 days of age, but a comparable rise did not occur in germ-cell depleted testes of irradiated rats. Levels of enzyme in various populations of testicular cells were highest in Sertoli (varying between 1800 and 6300 units/mg protein in cell maintained under different culture conditions), and lowest in peritubular myoid cells (about 1 unit/mg protein), with intermediate levels in germinal cells (ranging between 147 and 560 units/Mg protein in residual bodies, spermatocytes and spermatids). No protease inhibitor could be detected in germ-cell extracts. The addition to the medium in which Sertoli cells were in culture of particles which can be phagocytosed (autoclaved E. coli) resulted in an increased formation of plasminogen activator activity by Sertoli cells. A synergistic enhancement of enzyme production resulted following the addition of submaximal quantities of dibutyryl cyclic AMP and autoclaved bacteria to sertoli cells in culture. On the basis of these data, we suggest that the presence of advanced germinal cells during gonadal development may stimulate the synthesis of plasminogen activator by Sertoli cells, mediated in part by the phagocytosis of residual bodies by sertoli cells which occurs prior to spermiation.

  14. Human mast cell transcriptome project.

    PubMed

    Saito, H; Nakajima, T; Matsumoto, K

    2001-05-01

    After draft reading of the human genome sequence, systemic analysis of the transcriptome (the whole transcripts present in a cell) is progressing especially in commonly available cell types. Until recently, human mast cells were not commonly available. We have succeeded to generate a substantial number of human mast cells from umbilical cord blood and from adult peripheral blood progenitors. Then, we have examined messenger RNA selectively transcribed in these mast cells using high-density oligonucleotide probe arrays. Many unexpected but important transcripts were selectively expressed in human mast cells. We discuss the results obtained from transcriptome screening by introducing our data regarding mast-cell-specific genes.

  15. Mast cells and COPD.

    PubMed

    Mortaz, Esmaeil; Folkerts, Gert; Redegeld, Frank

    2011-08-01

    The pathogenesis of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune response to the inhalation of toxic particles and gases. Although tobacco smoking is the primary cause of this inhalation injury, many other environmental and occupational exposures contribute to the pathology of COPD. The immune inflammatory changes associated with COPD are linked to a tissue-repair and -remodeling process that increases mucus production and causes emphysematous destruction of the gas-exchanging surface of the lung. The common form of emphysema observed in smokers begins in the respiratory bronchioles near the thickened and narrowed small bronchioles that become the major site of obstruction in COPD. The inflamed airways of COPD patients contain several inflammatory cells including neutrophils, macrophages, T lymphocytes, and dendritic cells. The relative contribution of mast cells to airway injury and remodeling is not well documented. In this review, an overview is given on the possible role of mast cells and their mediators in the pathogenesis of COPD. Activation of mast cells and mast cell signaling in response to exposure to cigarette smoke is further discussed.

  16. Tetraspanins in Mast Cells

    PubMed Central

    Köberle, Martin; Kaesler, Susanne; Kempf, Wolfgang; Wölbing, Florian; Biedermann, Tilo

    2012-01-01

    Mast cells (MC) are key mediators of the immune system, most prominently known for their role in eliciting harmful allergic reactions. Mast cell mediator release (e.g. by degranulation) is triggered by FcεRI recognition of antigen – IgE complexes. Until today no therapeutic targeting of this and other mast cell activation pathways is established. Among possible new candidates there are tetraspanins that have been described on MC already several years ago. Tetraspanins are transmembrane proteins acting as scaffolds, mediating local clustering of their interaction partners, and thus amplify their activities. More recently, tetraspanins were also found to exert intrinsic receptor functions. Tetraspanins have been found to be crucial components of fundamental biological processes like cell motility and adhesion. In immune cells, they not only boost the effectiveness of antigen presentation by clustering MHC molecules, they are also key players in all kinds of degranulation events and immune receptor clustering. This review focuses on the contribution of tetraspanins clustered with FcεRI or residing in granule membranes to classical MC functions but also undertakes an outlook on the possible contribution of tetraspanins to newly described mast cell functions and discusses possible targets for drug development. PMID:22783251

  17. Secretory activity of mast cell during stress: effect of prolyl-glycyl-proline and Semax.

    PubMed

    Umarova, B A; Kopylova, G N; Smirnova, E A; Guseva, A A; Zhuikova, S E

    2003-10-01

    Stress increased secretory activity of mast cells in the mesentery and subcutaneous fat of rats. Intraperitoneal injection of Semax and prolyl-glycyl-proline in doses of 0.05 and 1 mg/kg, respectively, 1 h before stress abolished this effect. The test preparations did not modulate secretory activity of mast cells in unstressed animals. Semax and prolyl-glycyl-proline in vitro prevented activation of mast cells with synacten and acetylcholine. The stabilizing effect of peptides on mast cells probably determines their antiulcer activity.

  18. Peritoneal mast cell stabilization potential of Pothos scandens L

    PubMed Central

    Gupta, Saurabh; Duraiswamy, B.; Satishkumar, M. N.

    2013-01-01

    Objective: To investigate the peritoneal mast cell stabilization activity of Pothos scandens extracts Materials and Methods: Pothos scandens L. (family- Araceae) aerial part was successively extracted with ethanol and aqueous to prepare extract of the plant. The extracts of P. scandens were evaluated for stabilization of mast cell in rat allergic models. The extract of P. scandens ethanolic, 50% aqueous ethanolic and aqueous (1, 10 and 100 μg/ml) was studied for peritoneal mast cell stabilization activity in rat mesenteric preparation induced by C 48/80. Result: Preliminary phytochemical analysis revealed the presence of carbohydrates, fixed oil, proteins, alkaloids, glycosides, flavonoids and phenolic compounds. The ethanolic, 50% aqueous ethanolic and aqueous extracts of P. scandens L. showed dose dependent increase in the number of intact cells when compare with C48/80 at the concentration of 10 and 100 μg/ml. It virtues further work towards the isolation of phytoconstituents from this plant. Conclusion: This finding provides evidence that the P. scandens L. inhibits mast cell-derived immediate-type allergic reactions and mast cell degranulation. P. scandens has a potential as allergic anti- asthmatic agent. PMID:23542883

  19. Influence of ethanolic extract of Tephrosia purpurea Linn. on mast cells and erythrocytes membrane integrity.

    PubMed

    Gokhale, A B; Dikshit, V J; Damre, A S; Kulkarni, K R; Saraf, M N

    2000-08-01

    The ethanolic extract of T. purpurea Linn. was studied for its in vitro effect on rat mast cell degranulation and erythrocyte membrane integrity in vitro. The extract in concentration of 25-200 microg/ml showed a dose-dependant inhibition of rat mast cell degranulation induded by compound 48/80 and egg albumin. T. purpurea extract was found to inhibit haemolysis of erythrocytes induced by hypotonic solution but accelerated haemolysis induced by heat at a concentration of 100 microg/ml. The studies reveal that the ethanolic extract of T. purpurea may inhibit degranulation of mast cells by a mechanism other than membrane stabilization.

  20. Effects of B Cell Depletion on Early Mycobacterium tuberculosis Infection in Cynomolgus Macaques

    PubMed Central

    Phuah, Jiayao; Wong, Eileen A.; Gideon, Hannah P.; Maiello, Pauline; Coleman, M. Teresa; Hendricks, Matthew R.; Ruden, Rachel; Cirrincione, Lauren R.; Chan, John; Lin, Philana Ling

    2016-01-01

    Although recent studies in mice have shown that components of B cell and humoral immunity can modulate the immune responses against Mycobacterium tuberculosis, the roles of these components in human and nonhuman primate infections are unknown. The cynomolgus macaque (Macaca fascicularis) model of M. tuberculosis infection closely mirrors the infection outcomes and pathology in human tuberculosis (TB). The present study used rituximab, an anti-CD20 antibody, to deplete B cells in M. tuberculosis-infected macaques to examine the contribution of B cells and humoral immunity to the control of TB in nonhuman primates during the acute phase of infection. While there was no difference in the overall pathology, disease profession, and clinical outcome between the rituximab-treated and untreated macaques in acute infection, analyzing individual granulomas revealed that B cell depletion resulted in altered local T cell and cytokine responses, increased bacterial burden, and lower levels of inflammation. There were elevated frequencies of T cells producing interleukin-2 (IL-2), IL-10, and IL-17 and decreased IL-6 and IL-10 levels within granulomas from B cell-depleted animals. The effects of B cell depletion varied among granulomas in an individual animal, as well as among animals, underscoring the previously reported heterogeneity of local immunologic characteristics of tuberculous granulomas in nonhuman primates. Taken together, our data clearly showed that B cells can modulate the local granulomatous response in M. tuberculosis-infected macaques during acute infection. The impact of these alterations on disease progression and outcome in the chronic phase remains to be determined. PMID:26883591

  1. Partial Regulatory T Cell Depletion Prior to Schistosomiasis Vaccination Does Not Enhance the Protection

    PubMed Central

    Zhou, Sha; Xu, Zhipeng; Hoellwarth, Jason; Chen, Xiaojun; He, Lei; Zhang, Rongbo; Liu, Feng; Wang, Jun; Su, Chuan

    2012-01-01

    CD4+CD25+ regulatory T cells (Tregs) do not only influence self-antigen specific immune responses, but also dampen the protective effect induced by a number of vaccines. The impact of CD4+CD25+ Tregs on vaccines against schistosomiasis, a neglected tropical disease that is a major public health concern, however, has not been examined. In this study, a DNA vaccine encoding a 26 kDa glutathione S-transferase of Schistosoma japonicum (pVAX1-Sj26GST) was constructed and its potential effects were evaluated by depleting CD25+ cells prior to pVAX1-Sj26GST immunization. This work shows that removal of CD25+ cells prior to immunization with the pVAX1-Sj26GST schistosomiasis DNA vaccine significantly increases the proliferation of splenocytes and IgG levels. However, CD25+ cell-depleted mice immunized with pVAX1-Sj26GST show no improved protection against S. japonicum. Furthermore, depletion of CD25+ cells causes an increase in both pro-inflammatory cytokines (e.g. IFN-γ, GM-CSF and IL-4) and an anti-inflammatory cytokine (e.g. IL-10), with CD4+CD25- T cells being one of the major sources of both IFN-γ and IL-10. These findings indicate that partial CD25+ cell depletion fails to enhance the effectiveness of the schistosome vaccine, possibly due to IL-10 production by CD4+CD25- T cells, or other cell types, after CD25+ cell depletion during vaccination. PMID:22802961

  2. B-Cell Depletion Reduces the Maturation of Cerebral Cavernous Malformations in Murine Models.

    PubMed

    Shi, Changbin; Shenkar, Robert; Zeineddine, Hussein A; Girard, Romuald; Fam, Maged D; Austin, Cecilia; Moore, Thomas; Lightle, Rhonda; Zhang, Lingjiao; Wu, Meijing; Cao, Ying; Gunel, Murat; Louvi, Angeliki; Rorrer, Autumn; Gallione, Carol; Marchuk, Douglas A; Awad, Issam A

    2016-06-01

    Cerebral cavernous malformations (CCMs) are relatively common vascular malformations, characterized by increased Rho kinase (ROCK) activity, vascular hyper-permeability and the presence of blood degradation products including non-heme iron. Previous studies revealed robust inflammatory cell infiltration, selective synthesis of IgG, in situ antigen driven B-cell clonal expansion, and deposition of immune complexes and complement proteins within CCM lesions. We aimed to evaluate the impact of suppressing the immune response on the formation and maturation of CCM lesions, as well as lesional iron deposition and ROCK activity. Two murine models of heterozygous Ccm3 (Pdcd10), which spontaneously develop CCM lesions with severe and milder phenotypes, were either untreated or received anti-mouse BR3 to deplete B cells. Brains from anti-mouse BR3-treated mice exhibited significantly fewer mature CCM lesions and smaller lesions compared to untreated mice. B cell depletion halted the progression of lesions into mature stage 2 lesions but did not prevent their genesis. Non-heme iron deposition and ROCK activity was decreased in lesions of B cell depleted mice. This represents the first report of the therapeutic benefit of B-cell depletion in the development and progression of CCMs, and provides a proof of principle that B cells play a critical role in CCM lesion genesis and maturation. These findings add biologics to the list of potential therapeutic agents for CCM disease. Future studies would characterize the putative antigenic trigger and further define the mechanism of immune response in the lesions.

  3. 1-Fluoro-2,4-dinitrobenzene and its derivatives act as secretagogues on rodent mast cells.

    PubMed

    Manabe, Yohei; Yoshimura, Marie; Sakamaki, Kazuma; Inoue, Asuka; Kakinoki, Aya; Hokari, Satoshi; Sakanaka, Mariko; Aoki, Junken; Miyachi, Hiroyuki; Furuta, Kazuyuki; Tanaka, Satoshi

    2017-01-01

    Accumulating evidence suggests that activated mast cells are involved in contact hypersensitivity, although the precise mechanisms of their activation are still not completely understood. We investigated the potential of common experimental allergens to induce mast cell activation using murine bone marrow-derived cultured mast cells and rat peritoneal mast cells. Among these allergens, 1-chloro-2,4-dinitrobenzene and 1-fluoro-2,4-dinirobenzene (DNFB) were found to induce degranulation of rat peritoneal mast cells. DNFB-induced degranulation is accompanied by cytosolic Ca(2+) mobilization and is significantly inhibited by pertussis toxin, U73122 (a phospholipase C inhibitor), and BAPTA (a Ca(2+) chelator), raising the possibility that DNFB acts on the G protein-coupled receptors and activates Gi , which induces activation of phospholipase C, as well as known mast cell secretagogues, such as compound 48/80. DNFB could induce mast cell degranulation in the absence of serum proteins and IgE. Structure-activity relationship analyses revealed an inverse correlation between the degree of degranulation and the electron density of the C1 carbon of the DNFB derivatives. These findings raise a possibility that DNFB functions as a potent contact allergen through induction of cutaneous mast cell degranulation.

  4. Mast cells in rheumatic disease.

    PubMed

    Suurmond, Jolien; van der Velden, Daniël; Kuiper, Johan; Bot, Ilze; Toes, René E M

    2016-05-05

    Rheumatoid Arthritis is a chronic autoimmune disease with a complex disease pathogenesis leading to inflammation and destruction of synovial tissue in the joint. Several molecules lead to activation of immune pathways, including autoantibodies, Toll-Like Receptor ligands and cytokines. These pathways can cooperate to create the pro-inflammatory environment that results in tissue destruction. Each of these pathways can activate mast cells, inducing the release of a variety of inflammatory mediators, and in combination can markedly enhance mast cell responses. Mast cell-derived cytokines, chemokines, and proteases have the potential to induce recruitment of other leukocytes able to evoke tissue remodeling or destruction. Likewise, mast cells can secrete a plethora of factors that can contribute to tissue remodeling and fibroblast activation. Although the functional role of mast cells in arthritis pathogenesis in mice is not yet elucidated, the increased numbers of mast cells and mast cell-specific mediators in synovial tissue of rheumatoid arthritis patients suggest that mast cell activation in rheumatoid arthritis may contribute to its pathogenesis.

  5. Bacterial activation of mast cells.

    PubMed

    Chi, David S; Walker, Elaine S; Hossler, Fred E; Krishnaswamy, Guha

    2006-01-01

    Mast cells often are found in a perivascular location but especially in mucosae, where they may response to various stimuli. They typically associate with immediate hypersensitive responses and are likely to play a critical role in host defense. In this chapter, a common airway pathogen, Moraxella catarrhalis, and a commensal bacterium, Neiserria cinerea, are used to illustrate activation of human mast cells. A human mast cell line (HMC-1) derived from a patient with mast cell leukemia was activated with varying concentrations of heat-killed bacteria. Active aggregation of bacteria over mast cell surfaces was detected by scanning electron microscopy. The activation of mast cells was analyzed by nuclear factor-kappaB (NF-kappaB) activation and cytokine production in culture supernatants. Both M. catarrhalis and N. cinerea induce mast cell activation and the secretion of two key inflammatory cytokines, interleukin-6 and MCP-1. This is accompanied by NF-kappaB activation. Direct bacterial contact with mast cells appears to be essential for this activation because neither cell-free bacterial supernatants nor bacterial lipopolysaccharide induce cytokine secretion.

  6. Mast Cell Hyperplasia and Eosinophilia Induced by Ascaris Body Fluid

    PubMed Central

    Archer, G. T.; Binet, J.-L.

    1971-01-01

    Daily i.p. injections of dilute Ascaris body fluid into rats induced peritoneal eosinophilia and the formation of pin-point follicles in the omentum. The follicles comprised plasma cells, macrophages and fibroblasts together with large numbers of eosinophils and mast cells. Electron microscopy of eosinophils in the follicles revealed loss of cytoplasmic granules and numerous vesicular and tubular structures in the cytoplasm. The mast cells showed clear areas round the granules, suggesting dissolution of granule components. ImagesFigs. 4-6Figs. 7-8Figs. 13-14Figs. 9-10Figs. 1-3Figs. 11-12 PMID:5135540

  7. Overview of MAST results

    NASA Astrophysics Data System (ADS)

    Chapman, I. T.; Adamek, J.; Akers, R. J.; Allan, S.; Appel, L.; Asunta, O.; Barnes, M.; Ben Ayed, N.; Bigelow, T.; Boeglin, W.; Bradley, J.; Brünner, J.; Cahyna, P.; Carr, M.; Caughman, J.; Cecconello, M.; Challis, C.; Chapman, S.; Chorley, J.; Colyer, G.; Conway, N.; Cooper, W. A.; Cox, M.; Crocker, N.; Crowley, B.; Cunningham, G.; Danilov, A.; Darrow, D.; Dendy, R.; Diallo, A.; Dickinson, D.; Diem, S.; Dorland, W.; Dudson, B.; Dunai, D.; Easy, L.; Elmore, S.; Field, A.; Fishpool, G.; Fox, M.; Fredrickson, E.; Freethy, S.; Garzotti, L.; Ghim, Y. C.; Gibson, K.; Graves, J.; Gurl, C.; Guttenfelder, W.; Ham, C.; Harrison, J.; Harting, D.; Havlickova, E.; Hawke, J.; Hawkes, N.; Hender, T.; Henderson, S.; Highcock, E.; Hillesheim, J.; Hnat, B.; Holgate, J.; Horacek, J.; Howard, J.; Huang, B.; Imada, K.; Jones, O.; Kaye, S.; Keeling, D.; Kirk, A.; Klimek, I.; Kocan, M.; Leggate, H.; Lilley, M.; Lipschultz, B.; Lisgo, S.; Liu, Y. Q.; Lloyd, B.; Lomanowski, B.; Lupelli, I.; Maddison, G.; Mailloux, J.; Martin, R.; McArdle, G.; McClements, K.; McMillan, B.; Meakins, A.; Meyer, H.; Michael, C.; Militello, F.; Milnes, J.; Morris, A. W.; Motojima, G.; Muir, D.; Nardon, E.; Naulin, V.; Naylor, G.; Nielsen, A.; O'Brien, M.; O'Gorman, T.; Ono, Y.; Oliver, H.; Pamela, S.; Pangione, L.; Parra, F.; Patel, A.; Peebles, W.; Peng, M.; Perez, R.; Pinches, S.; Piron, L.; Podesta, M.; Price, M.; Reinke, M.; Ren, Y.; Roach, C.; Robinson, J.; Romanelli, M.; Rozhansky, V.; Saarelma, S.; Sangaroon, S.; Saveliev, A.; Scannell, R.; Schekochihin, A.; Sharapov, S.; Sharples, R.; Shevchenko, V.; Silburn, S.; Simpson, J.; Storrs, J.; Takase, Y.; Tanabe, H.; Tanaka, H.; Taylor, D.; Taylor, G.; Thomas, D.; Thomas-Davies, N.; Thornton, A.; Turnyanskiy, M.; Valovic, M.; Vann, R.; Walkden, N.; Wilson, H.; van Wyk, F.; Yamada, T.; Zoletnik, S.; MAST; MAST Upgrade Teams

    2015-10-01

    The Mega Ampère Spherical Tokamak (MAST) programme is strongly focused on addressing key physics issues in preparation for operation of ITER as well as providing solutions for DEMO design choices. In this regard, MAST has provided key results in understanding and optimizing H-mode confinement, operating with smaller edge localized modes (ELMs), predicting and handling plasma exhaust and tailoring auxiliary current drive. In all cases, the high-resolution diagnostic capability on MAST is complemented by sophisticated numerical modelling to facilitate a deeper understanding. Mitigation of ELMs with resonant magnetic perturbations (RMPs) with toroidal mode number nRMP = 2, 3, 4, 6 has been demonstrated: at high and low collisionality; for the first ELM following the transition to high confinement operation; during the current ramp-up; and with rotating nRMP = 3 RMPs. nRMP = 4, 6 fields cause less rotation braking whilst the power to access H-mode is less with nRMP = 4 than nRMP = 3, 6. Refuelling with gas or pellets gives plasmas with mitigated ELMs and reduced peak heat flux at the same time as achieving good confinement. A synergy exists between pellet fuelling and RMPs, since mitigated ELMs remove fewer particles. Inter-ELM instabilities observed with Doppler backscattering are consistent with gyrokinetic simulations of micro-tearing modes in the pedestal. Meanwhile, ELM precursors have been strikingly observed with beam emission spectroscopy (BES) measurements. A scan in beta at the L-H transition shows that pedestal height scales strongly with core pressure. Gyro-Bohm normalized turbulent ion heat flux (as estimated from the BES data) is observed to decrease with increasing tilt of the turbulent eddies. Fast ion redistribution by energetic particle modes depends on density, and access to a quiescent domain with ‘classical’ fast ion transport is found above a critical density. Highly efficient electron Bernstein wave current drive (1 A W-1) has been achieved

  8. Mast cells in gastrointestinal disorders.

    PubMed

    Bischoff, Stephan C

    2016-05-05

    Mast cells are constitutively found in the gastrointestinal (GI) tract. The three major physiological functions of GI mast cells comprise of - as far as we know - regulation of GI functions, namely epithelial and endothelial functions, crosstalk with the enteric nervous system, and contribution to the host defense against bacterial, viral and parasitic agents. A number of chronic GI diseases, including inflammatory bowel disease (Crohn's disease, ulcerative colitis), celiac disease, irritable bowel syndrome, and food allergies, are thought to be associated with mast cell hyperplasia and humoral activity. Clinical conditions characterized by a decrease in mast cell functionality are not known so far. In the present review, we summarize current evidence which show that human mast cells play a central role at the GI barrier, both in health and disease.

  9. The mast cell - B-cell axis in lung vascular remodeling and pulmonary hypertension.

    PubMed

    Breitling, Siegfried; Hui, Zhang; Zabini, Diana; Hu, Yijie; Hoffmann, Julia; Goldenberg, Neil M; Tabuchi, Arata; Buelow, Roland; Dos Santos, Claudia; Kuebler, Wolfgang Michael

    2017-02-24

    Over the past years, a critical role for the immune system and in particular, for mast cells, in the pathogenesis of pulmonary hypertension (PH) has emerged. However, the way in which mast cells promote PH is still poorly understood. Here, we investigated the mechanisms by which mast cells may contribute to PH, specifically focusing on the interaction between the innate and adaptive immune response and the role of B-cells and autoimmunity. Experiments were performed in Sprague Dawley rats and B-cell deficient JH-KO rats in the monocrotaline, sugen-hypoxia and the aortic banding model of PH. Hemodynamics, cell infiltration, IL-6 expression, and vascular remodeling were analyzed. Gene array analyses revealed constituents of immunoglobulins as most prominently regulated mast cell dependent genes in the lung in experimental PH. IL-6 was shown to link mast cells to B-cells, as a) IL-6 was upregulated and colocalized with mast cells and was reduced by mast cell stabilizers, and b) IL-6 or mast cell blockade reduced B-cells in lungs of monocrotaline-treated rats. A functional role for B-cells in PH was demonstrated, in that either blocking B-cells by an anti-CD20 antibody or B-cell deficiency in JH-KO rats attenuated right ventricular systolic pressure and vascular remodeling in experimental PH. We here identify a mast cell - B-cell axis driven by IL-6 as critical immune pathway in the pathophysiology of PH. Our results provide novel insights into the role of the immune system in PH, which may be therapeutically exploited by targeted immunotherapy.

  10. Palmitoylethanolamide regulates development of intestinal radiation injury in a mast cell dependent manner

    PubMed Central

    Wang, Junru; Zheng, Junying; Kulkarni, Ashwini; Wang, Wen; Garg, Sarita; Prather, Paul L.; Hauer-Jensen, Martin

    2014-01-01

    Background Mast cells and neuroimmune interactions regulate the severity of intestinal radiation mucositis, a dose-limiting toxicity during radiation therapy of abdominal malignancies. Aims Because endocannabinoids regulate intestinal inflammation, we investigated the effect of the cannabimimetic, palmitoylethanolamide (PEA), in a mast competent (+/+) and mast cell deficient (Ws/Ws) rat model. Methods Rats underwent localized, fractionated intestinal irradiation and received daily injections with vehicle or PEA from 1 day before until 2 weeks after radiation. Intestinal injury was assessed non-invasively by luminol bioluminescence, and, at 2 weeks, by histology, morphometry, and immunohistochemical analysis, gene expression analysis, and pathway analysis. Results Compared to +/+ rats, Ws/Ws rats sustained more intestinal structural injury (p=0.01), mucosal damage (p=0.02), neutrophil infiltration (p=0.0003), and collagen deposition (p=0.004). PEA reduced structural radiation injury (p=0.02), intestinal wall thickness (p=0.03), collagen deposition (p=0.03), and intestinal inflammation (p=0.02) in Ws/Ws rats, but not in +/+ rats. PEA inhibited mast cell-derived cellular immune response and anti-inflammatory IL-6 and IL-10 signaling, and activated the prothrombin pathway in +/+ rats. In contrast, while PEA suppressed non-mast cell derived immune responses, it increased anti-inflammatory IL-10 and IL-6 signaling and decreased activation of the prothrombin pathway in Ws/Ws rats. Conclusions These data demonstrate that the absence of mast cells exacerbate radiation enteropathy by mechanisms that likely involve the coagulation system, anti-inflammatory cytokine signaling, and the innate immune system; and that these mechanisms are regulated by PEA in a mast cell-dependent manner. The endocannabinoid system should be explored as target for mitigating intestinal radiation injury. PMID:24848354

  11. Mast cell sarcoma: clinical management.

    PubMed

    Weiler, Catherine R; Butterfield, Joseph

    2014-05-01

    Mast cell sarcoma is a disorder that results in abnormal mast cells as identified by morphology, special stains, and in some publications, c-kit mutation analysis. It affects animal species such as canines more commonly than humans. In humans it is a very rare condition, with variable clinical presentation. There is no standard therapy for the disorder. It can affect any age group. It is occasionally associated with systemic mastocytosis and/or urticaria pigmentosa. The prognosis of mast cell sarcoma in published literature is very poor in humans.

  12. Mast Wake Reduction by Shaping

    DTIC Science & Technology

    2005-11-03

    piercing masts, hydrofoil boats 4 and oilrig platforms. Incorporating the technology will also 5 reduce the wave heights generated by such marine...on the 4 leading and trailing edges of the mast. For example: a I 5 caliber ogive with no straight mid-sections results in a 6 thickness to chord ratio...trailing edges of the mast. More specifically a 1 3 caliber ogive with no straight mid-sections results in a 4 thickness to chord ratio of 0.5 and has

  13. Ets Factors Regulate Neural Stem Cell Depletion and Gliogenesis in Ras Pathway Glioma.

    PubMed

    Breunig, Joshua J; Levy, Rachelle; Antonuk, C Danielle; Molina, Jessica; Dutra-Clarke, Marina; Park, Hannah; Akhtar, Aslam Abbasi; Kim, Gi Bum; Hu, Xin; Bannykh, Serguei I; Verhaak, Roel G W; Danielpour, Moise

    2015-07-14

    As the list of putative driver mutations in glioma grows, we are just beginning to elucidate the effects of dysregulated developmental signaling pathways on the transformation of neural cells. We have employed a postnatal, mosaic, autochthonous glioma model that captures the first hours and days of gliomagenesis in more resolution than conventional genetically engineered mouse models of cancer. We provide evidence that disruption of the Nf1-Ras pathway in the ventricular zone at multiple signaling nodes uniformly results in rapid neural stem cell depletion, progenitor hyperproliferation, and gliogenic lineage restriction. Abolishing Ets subfamily activity, which is upregulated downstream of Ras, rescues these phenotypes and blocks glioma initiation. Thus, the Nf1-Ras-Ets axis might be one of the select molecular pathways that are perturbed for initiation and maintenance in glioma.

  14. Ex vivo T-cell depletion in allogeneic hematopoietic stem cell transplant: past, present and future.

    PubMed

    Saad, A; Lamb, L S

    2017-03-20

    The most common cause of post-transplant mortality in patients with hematological malignancy is relapse, followed by GvHD, infections, organ toxicity and second malignancy. Immune-mediated complications such as GvHD continue to be challenging, yet amenable to control through manipulation of the T-cell compartment of the donor graft with subsequent immunomodulation after transplant. However, risk of both relapse and infection increase concomitantly with T-cell depletion (TCD) strategies that impair immune recovery. In this review, we discuss the clinical outcome of current and emerging strategies of TCD in allogeneic hematopoietic stem cell transplant that have developed during the modern transplantation era, focusing specifically on ex vivo strategies that target selected T-cell subsets.Bone Marrow Transplantation advance online publication, 20 March 2017; doi:10.1038/bmt.2017.22.

  15. Pathogen-specific T cell depletion and reactivation of opportunistic pathogens in HIV infection.

    PubMed

    Geldmacher, Christof; Koup, Richard A

    2012-05-01

    During HIV infection, it is unclear why different opportunistic pathogens cause disease at different CD4 T cell count thresholds. Early work has shown that CD4 T cell depletion is influenced both by cellular activation status and expression of viral entry receptors. More recently, functional characteristics of the CD4 T cells, such as cytokine and chemokine production, have also been shown to influence cellular susceptibility to HIV. Here, we examine how functional differences in pathogen-specific CD4 T cells could lead to their differential loss during HIV infection. This may have implications for when different opportunistic infections occur, and a better understanding of the mechanisms for functional imprinting of antigen-specific T cells may lead to improvements in design of vaccines against HIV and opportunistic pathogens.

  16. Targeted Type 2 Alveolar Cell Depletion. A Dynamic Functional Model for Lung Injury Repair

    PubMed Central

    Garcia, Orquidea; Hiatt, Michael J.; Lundin, Amber; Lee, Jooeun; Reddy, Raghava; Navarro, Sonia; Kikuchi, Alex

    2016-01-01

    Type 2 alveolar epithelial cells (AEC2) are regarded as the progenitor population of the alveolus responsible for injury repair and homeostatic maintenance. Depletion of this population is hypothesized to underlie various lung pathologies. Current models of lung injury rely on either uncontrolled, nonspecific destruction of alveolar epithelia or on targeted, nontitratable levels of fixed AEC2 ablation. We hypothesized that discrete levels of AEC2 ablation would trigger stereotypical and informative patterns of repair. To this end, we created a transgenic mouse model in which the surfactant protein-C promoter drives expression of a mutant SR39TK herpes simplex virus-1 thymidine kinase specifically in AEC2. Because of the sensitivity of SR39TK, low doses of ganciclovir can be administered to these animals to induce dose-dependent AEC2 depletion ranging from mild (50%) to lethal (82%) levels. We demonstrate that specific levels of AEC2 depletion cause altered expression patterns of apoptosis and repair proteins in surviving AEC2 as well as distinct changes in distal lung morphology, pulmonary function, collagen deposition, and expression of remodeling proteins in whole lung that persist for up to 60 days. We believe SPCTK mice demonstrate the utility of cell-specific expression of the SR39TK transgene for exerting fine control of target cell depletion. Our data demonstrate, for the first time, that specific levels of type 2 alveolar epithelial cell depletion produce characteristic injury repair outcomes. Most importantly, use of these mice will contribute to a better understanding of the role of AEC2 in the initiation of, and response to, lung injury. PMID:26203800

  17. A mast-seeding desert shrub regulates population dynamics and behavior of its heteromyid dispersers.

    PubMed

    Auger, Janene; Meyer, Susan E; Jenkins, Stephen H

    2016-04-01

    Granivorous rodent populations in deserts are primarily regulated through precipitation-driven resource pulses rather than pulses associated with mast-seeding, a pattern more common in mesic habitats. We studied heteromyid responses to mast-seeding in the desert shrub blackbrush (Coleogyne ramosissima), a regionally dominant species in the Mojave-Great Basin Desert transition zone. In a 5-year study at Arches National Park, Utah, USA, we quantified spatiotemporal variation in seed resources in mast and intermast years in blackbrush-dominated and mixed desert vegetation and measured responses of Dipodomys ordii (Ord's kangaroo rat) and Perognathus flavescens (plains pocket mouse). In blackbrush-dominated vegetation, blackbrush seeds comprised >79% of seed production in a mast year, but 0% in the first postmast year. Kangaroo rat abundance in blackbrush-dominated vegetation was highest in the mast year, declined sharply at the end of the first postmast summer, and then remained at low levels for 3 years. Pocket mouse abundance was not as strongly associated with blackbrush seed production. In mixed desert vegetation, kangaroo rat abundance was higher and more uniform through time. Kangaroo rats excluded the smaller pocket mice from resource-rich patches including a pipeline disturbance and also moved their home range centers closer to this disturbance in a year of low blackbrush seed production. Home range size for kangaroo rats was unrelated to seed resource density in the mast year, but resource-poor home ranges were larger (P < 0.001) in the first postmast year, when resources were limiting. Blackbrush seeds are higher in protein and fat but lower in carbohydrates than the more highly preferred seeds of Indian ricegrass (Achnatherum hymenoides) and have similar energy value per unit of handling time. Kangaroo rats cached seeds of these two species in similar spatial configurations, implying that they were equally valued as stored food resources. Blackbrush mast

  18. Antibacterial agent triclosan suppresses RBL-2H3 mast cell function

    SciTech Connect

    Palmer, Rachel K.; Hutchinson, Lee M.; Burpee, Benjamin T.; Tupper, Emily J.; Pelletier, Jonathan H.; Kormendy, Zsolt; Hopke, Alex R.; Malay, Ethan T.; Evans, Brieana L.; Velez, Alejandro; Gosse, Julie A.

    2012-01-01

    Triclosan is a broad-spectrum antibacterial agent, which has been shown previously to alleviate human allergic skin disease. The purpose of this study was to investigate the hypothesis that the mechanism of this action of triclosan is, in part, due to effects on mast cell function. Mast cells play important roles in allergy, asthma, parasite defense, and carcinogenesis. In response to various stimuli, mast cells degranulate, releasing allergic mediators such as histamine. In order to investigate the potential anti-inflammatory effect of triclosan on mast cells, we monitored the level of degranulation in a mast cell model, rat basophilic leukemia cells, clone 2H3. Having functional homology to human mast cells, as well as a very well defined signaling pathway leading to degranulation, this cell line has been widely used to gain insight into mast-cell driven allergic disorders in humans. Using a fluorescent microplate assay, we determined that triclosan strongly dampened the release of granules from activated rat mast cells starting at 2 μM treatment, with dose-responsive suppression through 30 μM. These concentrations were found to be non-cytotoxic. The inhibition was found to persist when early signaling events (such as IgE receptor aggregation and tyrosine phosphorylation) were bypassed by using calcium ionophore stimulation, indicating that the target for triclosan in this pathway is likely downstream of the calcium signaling event. Triclosan also strongly suppressed F-actin remodeling and cell membrane ruffling, a physiological process that accompanies degranulation. Our finding that triclosan inhibits mast cell function may explain the clinical data mentioned above and supports the use of triclosan or a mechanistically similar compound as a topical treatment for allergic skin disease, such as eczema. -- Highlights: ►The effects of triclosan on mast cell function using a murine mast cell model. ►Triclosan strongly inhibits degranulation of mast cells.

  19. Immunotherapy and mast cell activation.

    PubMed

    Carlos, A G; Carlos, M L; Santos, M A; Pedro, E; Santos, S; Lopes-Pregal, A

    1998-10-01

    Tryptase is the more specific markers for mast cell activation and mediators release and can be used as an index of mast cell activation after challenge. Nasal provocation tests have been done in patients allergic to the pollen of Parietaria (pellitory wall) before and after specific systemic immunotherapy and tryptase release evaluated in nasal lavage fluid. After specific immunotherapy the concentration of tryptase in nasal lavage was significantly decreased to all the concentrations used in challenge and the peack of tryptase release was delayed. These results confirm that assays of tryptase in nasal fluid after nasal provocation are a reliable markers of mast cell activation. Immunotherapy with specific allergen decreases mast cell reactivity to the same allergen.

  20. Mast cell release of superoxide

    SciTech Connect

    Dileepan, K.N.; Simpson, K.M.; Stechschulte, D.J.

    1987-05-01

    The ability of rat serosal mast cells (MC) to release superoxide (O/sub 2//sup -/) upon activation by immunologic and nonimmunologic stimuli was investigated. Purified MC (90-95%) were either sensitized with monoclonal IgE reactive against dinitrophenyl bovine serum albumin (DNP-BSA) and challenged with DNP-BSA, or naive MC were treated with compound 48/80 or ionophore A23187. O/sub 2//sup -/ release was measured by O/sub 2//sup -/ dismutase (SOD)-sensitive reduction of cytochrome C and MC activation was assessed by the release of histamine or (/sup 14/C)5-hydroxytryptamine (5HT). The results reveal that activation of MC by 48/80 or immunologic challenge does not release O/sub 2//sup -/, although these stimuli induce substantial release of histamine and 5HT (40-70%). In contrast, A23187 released O/sub 2//sup -/ (3-6 nMols/10/sup 6/ MC) and histamine (40-80%). In mixed cell preparations containing MC and macrophages (M0), activation of MC with 48/80 resulted in inhibition of M0 O/sub 2//sup -/ release. The MC-mediated inhibition of O/sub 2//sup -/ production was not due to histamine or 5HT, but was due to MC-granule SOD. MC contain abundant quantities of SOD and, therefore, release O/sub 2//sup -/ only when its production exceeds the intracellular SOD threshold following activation with selective stimuli. In addition, the apparent differences in the mode and site of action of various stimuli on MC may contribute to the discriminative release of O/sub 2//sup -/.

  1. Systemic Effects of Ingested Lactobacillus Rhamnosus: Inhibition of Mast Cell Membrane Potassium (IKCa) Current and Degranulation

    PubMed Central

    Forsythe, Paul; Wang, Binxiang; Khambati, Ibrahim; Kunze, Wolfgang A.

    2012-01-01

    Exposure of the intestine to certain strains lactobacillus can have systemic immune effects that include the attenuation of allergic responses. Despite the central role of mast cells in allergic disease little is known about the effect of lactobacilli on the function of these cells. To address this we assessed changes in rat mast cell activation following oral treatment with a strain of Lactobacillus known to attenuate allergic responses in animal models. Sprague Dawley rats were fed with L.rhamnosus JB-1 (1×109) or vehicle control for 9 days. Mediator release from peritoneal mast cells (RPMC) was determined in response to a range of stimuli. Passive cutaneous anaphylaxis (PCA) was used to assess mast cell responses in vivo. The Ca2+ activated K+ channel (KCa3.1) current, identified as critical to mast cell degranulation, was monitored by whole cell patch-clamp. L.rhamnosus JB-1 treatment lead to significant inhibition of mast cell mediator release in response to a range of stimuli including IgE mediated activation. Furthermore, the PCA response was significantly reduced in treated rats. Patch-clamp studies revealed that RPMC from treated animals were much less responsive to the KCa3.1 opener, DCEBIO. These studies demonstrate that Ingestion of L.rhamnosus JB-1 leads to mast cell stabilization in rats and identify KCa3.1 as an immunomodulatory target for certain lactobacilli. Thus the systemic effects of certain candidate probiotics may include mast cell stabilization and such actions could contribute to the beneficial effect of these organisms in allergic and other inflammatory disorders. PMID:22815978

  2. Targeting mast cells in inflammatory diseases.

    PubMed

    Reber, Laurent L; Frossard, Nelly

    2014-06-01

    Although mast cells have long been known to play a critical role in anaphylaxis and other allergic diseases, they also participate in some innate immune responses and may even have some protective functions. Data from the study of mast cell-deficient mice have facilitated our understanding of some of the molecular mechanisms driving mast cell functions during both innate and adaptive immune responses. This review presents an overview of the biology of mast cells and their potential involvement in various inflammatory diseases. We then discuss some of the current pharmacological approaches used to target mast cells and their products in several diseases associated with mast cell activation.

  3. Effect of LED phototherapy (λ630 +/- 20nm) on mast cells during wound healing in hypothyroid

    NASA Astrophysics Data System (ADS)

    Paraguassú, Gardênia M.; De Castro, Isabele Cardoso V.; Vasconcelos, Rebeca M.; da Guarda, Milena G.; Rodriguez, Tânia T.; Ramalho, Maria José P.; Pinheiro, Antônio Luiz B.; Ramalho, Luciana Maria P.

    2014-02-01

    Hypothyroidism has been associated with the disruption of the body's metabolism, including the healing process. LED phototherapy has been studied using several healing models, but their effects on mast cells proliferation associated to hypothyroidism remains unknown. The aim of this study was to assess the effect LED (λ630+/-20nm) phototherapy on mast cells proliferation during tissue repair in hypothyroid rats. Under general anesthesia, a standard surgical wound (1cm2) was created on the dorsum of 24 male Wistar rats divided into 4 groups of 6 animals each: EC-Control Euthyroid; ED-Euthyroid+LED; HC-Control Hypothyroid and HD-Hypothyroid+LED. The irradiation started immediately after surgery and was repeated every other day for 7 days, when animals death occurred. Hypothyroidism was induced in rats with propylthiouracil (0.05g/100mL) administered orally for 4 weeks and maintained until the end of the experiment. The specimens removed were processed to wax and stained with toluidine blue for mast cell identification. The mast cell proliferation was significantly higher in HC group than in EC group (Mann Whitney, p<0.05), but when ED group was compared to HD group, no significant difference was found. Our results showed that there was increase of mast cells in the presence of hypothyroidism, prolonging the inflammatory phase of repair, and the LED light has a biomodulative effect on mast cell population, even when hipothyroidism was present.

  4. Transient Treg-cell depletion in adult mice results in persistent self-reactive CD4(+) T-cell responses.

    PubMed

    Nyström, Sofia N; Bourges, Dorothée; Garry, Sarah; Ross, Ellen M; van Driel, Ian R; Gleeson, Paul A

    2014-12-01

    Depletion of Foxp3(+) CD4(+) regulatory T cells (Treg) in adults results in chronic inflammation and autoimmune disease. However, the impact of transient Treg-cell depletion on self-reactive responses is poorly defined. Here, we studied the effect of transient depletion of Treg cells on CD4(+) T-cell responses to endogenous self-antigens. Short-term ablation of Treg cells in mice resulted in rapid activation of CD4(+) T cells, increased percentage of IFN-γ(+) and Th17 cells in lymphoid organs, and development of autoimmune gastritis. To track self-reactive responses, we analyzed the activation of naïve gastric-specific CD4(+) T cells. There was a dramatic increase in proliferation and acquisition of effector function of gastric-specific T cells in the stomach draining LNs of Treg-cell-depleted mice, compared with untreated mice, either during Treg-cell depletion or after Treg-cell reconstitution. Moreover, the hyperproliferation of gastric-specific T cells in the Treg-cell-ablated mice was predominantly antigen-dependent. Transient depletion of Treg cells resulted in a shift in the ratio of peripheral:thymic Treg cells in the reemerged Treg-cell population, indicating an altered composition of Treg cells. These findings indicate that transient Treg-cell depletion results in ongoing antigen-driven self-reactive T-cell responses and emphasize the continual requirement for an intact Treg-cell population.

  5. Treg-cell depletion promotes chemokine production and accumulation of CXCR3(+) conventional T cells in intestinal tumors.

    PubMed

    Akeus, Paulina; Langenes, Veronica; Kristensen, Jonas; von Mentzer, Astrid; Sparwasser, Tim; Raghavan, Sukanya; Quiding-Järbrink, Marianne

    2015-06-01

    Colorectal cancer (CRC) is one of the most prevalent tumor types worldwide and tumor-infiltrating T cells are crucial for anti-tumor immunity. We previously demonstrated that Treg cells from CRC patients inhibit transendothelial migration of conventional T cells. However, it remains unclear if local Treg cells affect lymphocyte migration into colonic tumors. By breeding APC(Min/+) mice with depletion of regulatory T cells mice, expressing the diphtheria toxin receptor under the control of the FoxP3 promoter, we were able to selectively deplete Treg cells in tumor-bearing mice, and investigate the impact of these cells on the infiltration of conventional T cells into intestinal tumors. Short-term Treg-cell depletion led to a substantial increase in the frequencies of T cells in the tumors, attributed by both increased infiltration and proliferation of T cells in the Treg-cell-depleted tumors. We also demonstrate a selective increase of the chemokines CXCL9 and CXCL10 in Treg-cell-depleted tumors, which were accompanied by accumulation of CXCR3(+) T cells, and increased IFN-γ mRNA expression. In conclusion, Treg-cell depletion increases the accumulation of conventional T cells in intestinal tumors, and targeting Treg cells could be a possible anti-tumor immunotherapy, which not only affects T-cell effector functions, but also their recruitment to tumors.

  6. Nonclinical evaluation of the potential for mast cell activation by an erythropoietin analog

    SciTech Connect

    Weaver, James L.

    2015-09-15

    The erythropoietin analog peginesatide was withdrawn from marketing due to unexpected severe anaphylactic reactions associated with administration of the multi-use formulation. The adverse events occurred rapidly following the first ever administration of the drug with most affected patients becoming symptomatic in less than 30 min. This is most consistent with an anaphylactoid reaction due to direct activation of mast cells. Laboratory evaluation was undertaken using rat peritoneal mast cells as the model system. Initial studies showed that high concentrations of the formulated drug as well as formulated vehicle alone could cause mast cell degranulation as measured by histamine release. The purified active drug was not able to cause histamine release whereas the vehicle filtrate and lab created drug vehicle were equally potent at causing histamine release. Individual formulations of vehicle leaving one component out showed that histamine release was due to phenol. Dose response studies with phenol showed a very sharp dose response curve that was similar in three buffer systems. Cellular analysis by flow cytometry showed that the histamine release was not due to cell death, and that changes in light scatter parameters consistent with degranulation were rapidly observed. Limited testing with primary human mast cells showed a similar dose response of histamine release with exposure to phenol. To provide in vivo confirmation, rats were injected with vehicle formulated with various concentrations of phenol via a jugular vein cannula. Significant release of histamine was detected in blood samples taken 2 min after dosing at the highest concentrations tested. - Highlights: • Peginesatide caused severe anaphylactoid reactions in 0.2% of patients. • Both formulated drug and vehicle cause degranulation of rat mast cells. • Phenol was identified as the vehicle component causing degranulation. • Human mast cells show similar dose response to phenol as rat mast cells

  7. Cell death by pyroptosis drives CD4 T-cell depletion in HIV-1 infection

    NASA Astrophysics Data System (ADS)

    Doitsh, Gilad; Galloway, Nicole L. K.; Geng, Xin; Yang, Zhiyuan; Monroe, Kathryn M.; Zepeda, Orlando; Hunt, Peter W.; Hatano, Hiroyu; Sowinski, Stefanie; Muñoz-Arias, Isa; Greene, Warner C.

    2014-01-01

    The pathway causing CD4 T-cell death in HIV-infected hosts remains poorly understood although apoptosis has been proposed as a key mechanism. We now show that caspase-3-mediated apoptosis accounts for the death of only a small fraction of CD4 T cells corresponding to those that are both activated and productively infected. The remaining over 95% of quiescent lymphoid CD4 T cells die by caspase-1-mediated pyroptosis triggered by abortive viral infection. Pyroptosis corresponds to an intensely inflammatory form of programmed cell death in which cytoplasmic contents and pro-inflammatory cytokines, including IL-1β, are released. This death pathway thus links the two signature events in HIV infection--CD4 T-cell depletion and chronic inflammation--and creates a pathogenic vicious cycle in which dying CD4 T cells release inflammatory signals that attract more cells to die. This cycle can be broken by caspase 1 inhibitors shown to be safe in humans, raising the possibility of a new class of `anti-AIDS' therapeutics targeting the host rather than the virus.

  8. Cytoskeleton in Mast Cell Signaling

    PubMed Central

    Dráber, Pavel; Sulimenko, Vadym; Dráberová, Eduarda

    2012-01-01

    Mast cell activation mediated by the high affinity receptor for IgE (FcεRI) is a key event in allergic response and inflammation. Other receptors on mast cells, as c-Kit for stem cell factor and G protein-coupled receptors (GPCRs) synergistically enhance the FcεRI-mediated release of inflammatory mediators. Activation of various signaling pathways in mast cells results in changes in cell morphology, adhesion to substrate, exocytosis, and migration. Reorganization of cytoskeleton is pivotal in all these processes. Cytoskeletal proteins also play an important role in initial stages of FcεRI and other surface receptors induced triggering. Highly dynamic microtubules formed by αβ-tubulin dimers as well as microfilaments build up from polymerized actin are affected in activated cells by kinases/phosphatases, Rho GTPases and changes in concentration of cytosolic Ca2+. Also important are nucleation proteins; the γ-tubulin complexes in case of microtubules or Arp 2/3 complex with its nucleation promoting factors and formins in case of microfilaments. The dynamic nature of microtubules and microfilaments in activated cells depends on many associated/regulatory proteins. Changes in rigidity of activated mast cells reflect changes in intermediate filaments build up from vimentin. This review offers a critical appraisal of current knowledge on the role of cytoskeleton in mast cells signaling. PMID:22654883

  9. Mast cell ontogeny: an historical overview.

    PubMed

    Ribatti, Domenico; Crivellato, Enrico

    2014-01-01

    Mast cells were first identified by Paul Ehrlich in 1878, when he was still a medical student. Many fundamental aspects of mast cell ontogeny have been elucidated since Ehrlich's first identification. Demonstration of mast cell derivation from bone marrow precursors could be established in 1977 when Kitamura's group first showed reconstitution of mast cells in mast cell-deficient mice by the adaptive transfer of wild type bone marrow and indicated that these cells were of hematopoietic origin. It is now definitively established that development of mast cells in bone marrow occurs along the myeloid pathway. However, several aspects need further clarification. In particular, identification and chemical characterization of growth factors expressing mast cell differentiating properties and the relationship between mast cell and basophils developmental pathways.

  10. A mast cell secretagogue, compound 48/80, prevents the accumulation of hyaluronan in lung tissue injured by ionizing irradiation

    SciTech Connect

    Nilsson, K.; Bjermer, L.; Hellstroem, S.H.; Henriksson, R.; Haellgren, R. )

    1990-02-01

    Irradiation with a single dose of 30 Grey on the basal regions of the lungs of Sprague-Dawley rats induced a peribronchial and alveolar inflammation. Infiltration of mast cells in the edematous alveolar interstitial tissue and also in the peribronchial tissue were characteristic features of the lesion. The appearance of mast cells was already seen 4 wk after irradiation and by weeks 6 to 8 there was a heavy infiltration. The staining properties suggested that they were connective tissue-type mast cells. The infiltration of mast cells was paralleled by an accumulation of hyaluronan (hyaluronic acid) in the alveolar interstitial tissue 6 and 8 wk after irradiation. The recovery of hyaluronan (HA) during bronchoalveolar lavage (BAL) of the lungs also increased at this time. Treatment with a mast cell secretagogue, compound 48/80, induced a distinct reduction of granulated mast cells in the alveolar tissue. Regular treatment with compound 48/80 from the time of irradiation considerably reduced the HA recovery during BAL and the HA accumulation in the interstitial tissue but did not affect the interstitial infiltration of mononuclear cells and polymorphonuclear leukocytes. By contrast, an accumulation of HA in the alveolar interstitial space was induced when compound 48/80 was given not until mast cell infiltration of the lung had started. The effects of compound 48/80 indicate that the connective tissue response after lung irradiation is dependent on whether or not mast cell degranulation is induced before or after the mast cell infiltration of the alveolar tissue.

  11. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    NASA Astrophysics Data System (ADS)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  12. 30 CFR 56.7004 - Drill mast.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation...

  13. 30 CFR 57.7004 - Drill mast.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is...

  14. 30 CFR 56.7004 - Drill mast.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation...

  15. 30 CFR 57.7004 - Drill mast.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is...

  16. 30 CFR 56.7004 - Drill mast.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation...

  17. 30 CFR 57.7004 - Drill mast.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is...

  18. 30 CFR 57.7004 - Drill mast.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is...

  19. 30 CFR 56.7004 - Drill mast.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation...

  20. 30 CFR 56.7004 - Drill mast.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation...

  1. 30 CFR 57.7004 - Drill mast.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is...

  2. 46 CFR 111.05-9 - Masts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Masts. 111.05-9 Section 111.05-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-9 Masts. Each nonmetallic mast and...

  3. Mast cell infiltrates in vulvodynia represent secondary and idiopathic mast cell hyperplasias.

    PubMed

    Regauer, Sigrid; Eberz, Barbara; Beham-Schmid, Christine

    2015-05-01

    Mast cell infiltrates in tissues of vulvodynia are common, but they have not been characterized for criteria of neoplastic mast cell disease or correlated with patient's concomitant diseases associated with increased mast cells. Formalin-fixed specimens of 35 patients with vulvodynia were evaluated immunohistochemically with antibodies to CD 3,4,8,20,117c and human mast cell tryptase, and for WHO-criteria of neoplastic mastocytosis (>25% spindled mast cell, CD25 expression, point mutations of the c-kit gene (D816V), and chronically elevated serum tryptase levels). Only 20/35 specimens showed a T-lymphocyte dominant inflammatory infiltrate on HE-stained sections, but all showed mast cells. 4/35 biopsies showed <10 mast cells/mm(2) , 15/35 specimens 40-60 mast cells/mm(2) and 16/35 specimens >60 mast cells/mm(2) (average 80/mm(2) ). Control tissue contained typically <10 mast cells/mm(2) . Spindling, CD25-expression, c-kit gene mutations, or increased serum tryptase levels were not detected. 26/35 (74%) patients had concomitant autoimmune diseases, psoriasis, atopy, various allergies, preceding infections. Independent of the subtype of vulvodynia, the majority of mast cell rich biopsies with >40 mast cells/mm(2) were classified as a secondary mast cell disorder reflecting an activated immune system in 75% of vulvodynia patients. Patients with increased mast cells may benefit from medical therapy targeting mast cells.

  4. Effect of sugammadex on rocuronium induced changes in pancreatic mast cells.

    PubMed

    Kalkan, Yıldıray; Tumkaya, Levent; Bostan, Habib; Tomak, Yakup; Altuner, Durdu; Yilmaz, Adnan; Erdivanli, Başar; Bedir, Recep; Yalcin, Alper; Turan, Alparslan

    2015-08-01

    Mast cells play a vital role in hypersensitivity reactions. Rocuronium is known to cause mast cell mobilization, hypersensitivity, and pancreatitis. The aim of this study was to investigate the effects of sugammadex on pancreatic changes due to rocuronium. A total of 42 Sprague-Dawley male rats were divided into six equal groups to receive either rocuronium 1 mg/kg intravenously (i.v., R group), rocuronium 1 mg/kg + sugammadex 16 mg/kg i.v. (RS16 group), rocuronium 1 mg/kg + sugammadex 96 mg/kg i.v. (RS96 group), sugammadex 16 mg/kg (S16), sugammadex 96 mg/kg i.v. (S96 group), or 0.9% sodium chloride (control group). Sugammadex was administered 5s later following rocuronium. In R group, mast count was higher, and the distribution rate of granules and nuclear changes were different compared with other groups. Distribution rate of granules in groups S16 and S96 were similar to the control group and lower compared with other groups. The amount of mast cells and granule density in groups RS16 and RS96 was lower compared with R group. The amount of mast cells in groups RS16 and RS96 was significantly lower compared with other treatment groups. These results suggest that sugammadex may have an inhibitory effect on mobilization and morphological changes in pancreatic mast cells induced by administration of rocuronium and sugammadex in rats.

  5. Efficacy of B cell Depletion Therapy on Joint Flare is Associated with Increased Lymphatic Flow

    PubMed Central

    Li, Jie; Ju, Yawen; Bouta, Echoe M.; Xing, Lianping; Wood, Ronald W.; Kuzin, Igor; Bottaro, Andrea; Ritchlin, Christopher T.; Schwarz, Edward M.

    2012-01-01

    Objective B cell depletion therapy (BCDT) ameliorates rheumatoid arthritis by mechanisms that are incompletely understood. Arthritic flare in tumor necrosis factor transgenic (TNF-Tg) mice is associated with efferent lymph node (LN) “collapse,” triggered by B cell translocation into lymphatic spaces and decreased lymphatic drainage. We examined whether BCDT efficacy is associated with restoration of lymphatic drainage due to removal of obstructing nodal B cells. Methods We developed contrast-enhancement (CE) MRI imaging, near-infrared indocyanine green (NIR-ICG) imaging, and intravital immunofluorescent imaging to longitudinally assess synovitis, lymphatic flow, and cell migration in lymphatic vessels in TNF-Tg mice. We tested to see if BCDT efficacy is associated with restoration of lymphatic draining and cell egress from arthritic joints. Results Unlike active lymphatics to normal and pre-arthritic knees, afferent lymphatic vessels to collapsed LNs in inflamed knees do not pulse. Intravital immunofluorescent imaging demonstrated that CD11b+ monocytes/macrophages in lymphatic vessels afferent to expanding LN travel at high velocity (186 ± 37 micrometer/sec), while these cells are stationary in lymphatic vessels afferent to collapsed PLN. BCDT of flaring TNF-Tg mice significantly decreased knee synovial volume by 50% from the baseline level, and significantly increased lymphatic clearance versus placebo (p<0.05). This increased lymphatic drainage restored macrophages egress from inflamed joints without recovery of the lymphatic pulse. Conclusion These results support a novel mechanism in which BCDT of flaring joints lessens inflammation by increasing lymphatic drainage and subsequent migration of cells and cytokines from the synovial space. PMID:23002006

  6. Germinal Center B Cell Depletion Diminishes CD4+ Follicular T Helper Cells in Autoimmune Mice

    PubMed Central

    Yusuf, Isharat; Stern, Jessica; McCaughtry, Tom M.; Gallagher, Sandra; Sun, Hong; Gao, Changshou; Tedder, Thomas; Carlesso, Gianluca; Carter, Laura; Herbst, Ronald; Wang, Yue

    2014-01-01

    Background Continuous support from follicular CD4+ T helper (Tfh) cells drives germinal center (GC) responses, which last for several weeks to produce high affinity memory B cells and plasma cells. In autoimmune Sle1 and NZB/W F1 mice, elevated numbers of Tfh cells persist, promoting the expansion of self-reactive B cells. Expansion of circulating Tfh like cells have also been described in several autoimmune diseases. Although, the signals required for Tfh differentiation have now been well described, the mechanisms that sustain the maintenance of fully differentiated Tfh are less understood. Recent data demonstrate a role for GC B cells for Tfh maintenance after protein immunization. Methods and Finding Given the pathogenic role Tfh play in autoimmune disease, we explored whether B cells are required for maintenance of autoreactive Tfh. Our data suggest that the number of mature autoreactive Tfh cells is controlled by GC B cells. Depletion of B cells in Sle1 autoimmune mice leads to a dramatic reduction in Tfh cells. In NZB/W F1 autoimmune mice, similar to the SRBC immunization model, GC B cells support the maintenance of mature Tfh, which is dependent mainly on ICOS. The CD28-associated pathway is dispensable for Tfh maintenance in SRBC immunized mice, but is required in the spontaneous NZB/W F1 model. Conclusion These data suggest that mature Tfh cells require signals from GC B cells to sustain their optimal numbers and function in both autoimmune and immunization models. Thus, immunotherapies targeting B cells in autoimmune disease may affect pathogenic Tfh cells. PMID:25101629

  7. Role of mast cell in the late phase of contact hypersensitivity induced by trimellitic anhydride

    PubMed Central

    Chai, Ok Hee

    2015-01-01

    Mast cells are known as effector cells of IgE-mediated allergic responses, but role of mast cells in contact hypersensitivity (CHS) has been considered controversial. In this study, we investigated role of mast cell in trimellitic anhydride (TMA)-induced CHS. The mice were sensitized to TMA on the back and repeatedly challenged with TMA on the left ear at 1-week intervals. The ear after challenge showed biphasic responses. The repetition of TMA challenge shifted in time course of ear response and enlarged the extent of early and late phase reactions in proportion to the frequency of TMA challenges in C57BL/6 mice. In late phase reaction, peak of ear response by single challenge showed at 24 hours after challenge, but the peak by repeat challenges at 8 hours after the last challenge. Number of mast cells and eosinophils per unit area increased in proportion to frequency of TMA challenges. However, mast cell-deficient WBB6F1/J-KitW/KitW-v mice developed the late phase reaction without the early phase reaction. The repetition of TMA challenge shifted in time course of ear response and enlarged the extent of ear response and the infiltration of eosinophils. The magnitude of these responses observed according to the frequency of the TMA challenge in mast cell-deficient WBB6F1/J-KitW/KitW-v mice was significantly lower than that in C57BL/6 mice. Also TMA elicited mast cell degranulation and histamine release from rat peritoneal mast cells in a concentration-dependent manner. Conclusively, TMA induces the early and late phase reactions in CHS, and mast cells may be required for TMA-induced CHS. PMID:26770872

  8. Mast Cells in Allergic Diseases and Mastocytosis

    PubMed Central

    Marquardt, Diana L.; Wasserman, Stephen I.

    1982-01-01

    Mast cells with their stores of vasoactive and chemotactic mediators are central to the pathogenesis of allergic diseases. The cross-linking of receptorbound IgE molecules on the surface of mast cells initiates a complex chain of events, including calcium ion influx, phospholipid methylation and turnover and cyclic nucleotide metabolism, ultimately resulting in the release of mediators of immediate hypersensitivity. These mast cell mediators are important in smooth muscle reactivity, in the recruitment of eosinophilic and neutrophilic leukocytes and in the generation of secondary chemical mediators. Histologic evidence of mast cell degranulation, biochemical evidence of mast cell mediators in blood and tissues and clinical evidence of signs and symptoms reproducible by these mediators have strongly supported the crucial role of mast cells in asthma, urticaria, anaphylaxis, rhinitis and mastocytosis. Because of their unique location at host environment interfaces, mast cells may both participate in allergic diseases and promote homeostasis. ImagesFigure 1.Figure 2.Figure 3. PMID:6293204

  9. Lipid Rafts in Mast Cell Biology

    PubMed Central

    Silveira e Souza, Adriana Maria Mariano; Mazucato, Vivian Marino; Jamur, Maria Célia; Oliver, Constance

    2011-01-01

    Mast cells have long been recognized to have a direct and critical role in allergic and inflammatory reactions. In allergic diseases, these cells exert both local and systemic responses, including allergic rhinitis and anaphylaxis. Mast cell mediators are also related to many chronic inflammatory conditions. Besides the roles in pathological conditions, the biological functions of mast cells include roles in innate immunity, involvement in host defense mechanisms against parasites, immunomodulation of the immune system, tissue repair, and angiogenesis. Despite their growing significance in physiological and pathological conditions, much still remains to be learned about mast cell biology. This paper presents evidence that lipid rafts or raft components modulate many of the biological processes in mast cells, such as degranulation and endocytosis, play a role in mast cell development and recruitment, and contribute to the overall preservation of mast cell structure and organization. PMID:21490812

  10. Mast Cell Proteases and Inflammation

    PubMed Central

    Dai, Hongyan; Korthuis, Ronald J.

    2011-01-01

    Mast cells are best known for their role in allergic reactions but are also now recognized for their important contributions to a number of disparate inflammatory conditions through the release of inflammatory mediators, serglycin and other proteoglycans, and proteases. Because these tissue resident inflammatory cells express proteases in such great abundance and their enzymatic activity results in cleavage of a multitude of proteins and peptides, which in turn modify tissue function, their substrate specificity, tissue distribution, and mode of action have become the subjects of great interest. Although mast cell protease-dependent proteolysis is critical to host defense against invading pathogens, regulation of these hydrolytic enzymes is essential to limiting self-induced damage as well. Indeed, dysregulated release of mast cell proteases is now recognized to contribute to the pathogenesis of a number of inflammatory conditions including asthma, abdominal aortic aneurysm formation, vessel damage in atherosclerosis and hypertension, arthritis, and ischemia/reperfusion injury. Understanding how mast cell proteases contribute to inflammation will thus help unravel molecular mechanisms that underlie such immunologic disorders and will help identify new therapeutic targets for drug development. PMID:22125569

  11. SuperCam_MastUnit

    NASA Astrophysics Data System (ADS)

    Deleuze, M. D.; Bernardi, P. B.; Caïs, Ph. C.; Perez, R. P.; Rees, J. M. R.; Pares, L. P.; Dubois, B. D.; Parot, Y. P.; Quertier, B. Q.; Maurice, S. M.; Maccabe, K. M.; Wiens, R. W.; Rull, F. R.

    2016-10-01

    This paper will describe and give a development status of SuperCam's mast unit. SuperCam will be carried on the Mars 2020 rover, and consists in an enhanced version of the ChemCam LIBS which is still performing at the surface of Mars, on Curiosity.

  12. Stimulation of mast cells leads to cholesterol accumulation in macrophages in vitro by a mast cell granule-mediated uptake of low density lipoprotein

    SciTech Connect

    Kokkonen, J.O.; Kovanen, P.T.

    1987-04-01

    The uptake of low density lipoprotein (LDL) by cultured mouse macrophages was markedly promoted by isolated rat mast cell granules present in the culture medium. The granule-mediated uptake of /sup 125/I-LDL enhanced the rate of cholesteryl ester synthesis in the macrophages, the result being accumulation of cholesteryl esters in these cells. Binding of LDL to the granules was essential for the granule-mediated uptake of LDL by macrophages, for the uptake process was prevented by treating the granules with avidin or protamine chloride or by treating LDL with 1,2-cyclohexanedione, all of which inhibit the binding of LDL to the granules. Inhibition of granule phagocytosis by the macrophages with cytochalasin B also abolished the granule-mediated uptake of LDL. Finally, mouse macrophage monolayers and LDL were incubated in the presence of isolated rat serosal mast cells. Stimulation of the mast cells with compound 48/80, a degranulating agent, resulted in dose-dependent release of secretory granules from the mast cells and a parallel increase in /sup 14/C cholesteryl ester synthesis in the macrophages. The results show that, in this in vitro model, the sequence of events leading to accumulation of cholesteryl esters in macrophages involves initial stimulation of mast cells, subsequent release of their secretory granules, binding of LDL to the exocytosed granules, and, finally, phagocytosis of the LDL-containing granules by macrophages.

  13. A murine herpesvirus closely related to ubiquitous human herpesviruses causes T-cell depletion.

    PubMed

    Patel, Swapneel J; Zhao, Guoyan; Penna, Vinay R; Park, Eugene; Lauron, Elvin J; Harvey, Ian B; Beatty, Wandy L; Plougastel-Douglas, Beatrice; Poursine-Laurent, Jennifer; Fremont, Daved H; Wang, David; Yokoyama, Wayne M

    2017-02-08

    clinical ramifications of roseolovirus infection in humans have been hypothesized, but studies showing definitive causative relationships between infection and disease susceptibility are lacking. Here we show that MRV infects the thymus and causes T-cell depletion, suggesting that other roseoloviruses may have similar properties.

  14. Listeria monocytogenes induces mast cell extracellular traps.

    PubMed

    Campillo-Navarro, Marcia; Leyva-Paredes, Kahiry; Donis-Maturano, Luis; González-Jiménez, Marco; Paredes-Vivas, Yuriria; Cerbulo-Vázquez, Arturo; Serafín-López, Jeanet; García-Pérez, Blanca; Ullrich, Stephen E; Flores-Romo, Leopoldo; Pérez-Tapia, Sonia M; Estrada-Parra, Sergio; Estrada-García, Iris; Chacón-Salinas, Rommel

    2017-02-01

    Mast cells play an essential role in different immunological phenomena including allergy and infectious diseases. Several bacteria induce mast cell activation leading to degranulation and the production of several cytokines and chemokines. However, mast cells also have different microbicidal activities such as phagocytosis and the release of DNA with embedded granular proteins known as Mast Cell Extracellular Traps (MCETs). Although previous reports indicate that extracellular bacteria are able to induce MCETs little is known if intracellular bacteria can induce these structures. In this work, we evaluated MCETs induction by the intracellular bacteria Listeria monocytogenes. We found that mast cells released DNA after stimulation with L. monocytogenes, and this DNA was complexed to histone and tryptase. Before extracellular DNA release, L. monocytogenes induced modifications to the mast cell nuclear envelope and DNA was detected outside the nucleus. L. monocytogenes stimulated mast cells to produce significant amounts of reactive oxygen species (ROS) and blocking NADPH oxidase diminished DNA release by mast cells. Finally, MCETs showed antimicrobial activity against L. monocytogenes that was partially blocked when β-hexosaminidase activity was inhibited. These results show that L. monocytogenes induces mast cells to produce microbicidal MCETs, suggesting a role for mast cells in containing infection beyond the induction of inflammation.

  15. Changes in mast cells and in permeability of mesenteric microvessels under the effect of immobilization and electrostimulation

    NASA Technical Reports Server (NTRS)

    Gorizontova, M. P.

    1980-01-01

    It was shown that a reduction in the amount of mast cells in the mesentery and an increase in their degranulation was accompanied by an increase in vascular permeability of rat mesentery. It is supposed that immobilization and electrostimulation causing degranulation of mast cells prompted histamine and serotonin release from them, thus increasing the permeability of the venular portion of the microvascular bed. Prophylactic use of esculamin preparation with P-vitaminic activity decreased mast cell degranulation, which apparently prolonged the release of histamine and serotonin from them and normalized vascular permeability.

  16. A comparative study of mast cells and eosinophil leukocytes in the mammalian testis.

    PubMed

    Anton, F; Morales, C; Aguilar, R; Bellido, C; Aguilar, E; Gaytán, F

    1998-05-01

    The existence of a physiological integration between the immune and endocrine systems has long been recognized. In spite of the abundant literature data on the presence of cells of the immune system in the testis, mast cells and eosinophil leukocytes have received little attention. We have studied the presence, distribution and numbers of mast cells and eosinophils in the testes of 12 mammalian species. Mast cells were frequently found in equine (stallion, ass and mule) and human testis, whereas eosinophils were nearly absent. On the contrary, eosinophils were abundant in the hare testis, while mast cells were lacking. Both cells types were present in high numbers in swine (wild and domestic boar) testis. Otherwise, mast cells and eosinophils were absent from the testicular parenchyma of several species (rat, dog, cat, bull and deer), although they were present, in most cases, around blood vessels in the tunica albuginea. The presence of high numbers of mast cells and/or eosinophil leukocytes in the testicular parenchyma of some species suggest a role for these cells in local regulatory pathways.

  17. Asymmetric divertor biasing in MAST

    NASA Astrophysics Data System (ADS)

    Helander, P.; Cohen, R.; Counsell, G. C.; Ryutov, D. D.

    2002-11-01

    Experiments are being carried out on the Mega-Ampere Spherical Tokamak (MAST) where the divertor tiles are electrically biased in a toroidally alternating way. The aim is to induce convective cells in the divertor plasma, broaden the SOL and reduce the divertor heat load. This paper describes the underlying theory and experimental results. Criteria are presented for achieving strong broadening and exciting shear-flow turbulence in the SOL, and properties of the expected turbulence are derived. It is also shown that magnetic shear near the X-point is likely to confine the potential perturbations to the divertor region, leaving the part of the SOL that is in direct contact with the core plasma intact. Preliminary comparison of the theory with MAST data is encouraging: the distortion of the heat deposition pattern, its broadening, and the incremental heat load are qualitatively in agreement; quantitative comparisons are underway.

  18. The role of mast cells in atherosclerosis.

    PubMed

    Wezel, A; Quax, P H A; Kuiper, J; Bot, I

    2015-01-01

    Rupture of an atherosclerotic plaque is the major underlying cause of adverse cardiovascular events such as myocardial infarction or stroke. Therapeutic interventions should therefore be directed towards inhibiting growth of atherosclerotic lesions as well as towards prevention of lesion destabilization. Interestingly, the presence of mast cells has been demonstrated in both murine and human plaques, and multiple interventional murine studies have pointed out a direct role for mast cells in early and late stages of atherosclerosis. Moreover, it has recently been described that activated lesional mast cells correlate with major cardiovascular events in patients suffering from cardiovascular disease. This review focuses on the effect of different mast cell derived mediators in atherogenesis and in late stage plaque destabilization. Also, possible ligands for mast cell activation in the context of atherosclerosis are discussed. Finally, we will elaborate on the predictive value of mast cells, together with therapeutic implications, in cardiovascular disease.

  19. Mast cells as effectors in atherosclerosis.

    PubMed

    Bot, Ilze; Shi, Guo-Ping; Kovanen, Petri T

    2015-02-01

    The mast cell is a potent immune cell known for its functions in host defense responses and diseases, such as asthma and allergies. In the past years, accumulating evidence established the contribution of the mast cell to cardiovascular diseases as well, in particular, by its effects on atherosclerotic plaque progression and destabilization. Through its release not only of mediators, such as the mast cell-specific proteases chymase and tryptase, but also of growth factors, histamine, and chemokines, activated mast cells can have detrimental effects on its immediate surroundings in the vessel wall. This results in matrix degradation, apoptosis, and enhanced recruitment of inflammatory cells, thereby actively contributing to cardiovascular diseases. In this review, we will discuss the current knowledge on mast cell function in cardiovascular diseases and speculate on potential novel therapeutic strategies to prevent acute cardiovascular syndromes via targeting of mast cells.

  20. Phenotypic changes of bone marrow-derived mast cells after intraperitoneal transfer into W/Wv mice that are genetically deficient in mast cells

    PubMed Central

    1987-01-01

    The ability of mouse IL-3-dependent, bone marrow culture-derived mast cells (BMMC) to generate serosal mast cells (SMC) in vivo after adoptive transfer to mast cell-deficient mice has been defined by chemical and immunochemical criteria. BMMC differentiated and grown from WBB6F1-+/+ mouse progenitor cells in medium containing PWM/splenocyte-conditioned medium synthesized a approximately 350,000 Mr protease-resistant proteoglycan bearing approximately 55,000 Mr glycosaminoglycans, as defined by gel filtration of each. Approximately 85% of the glycosaminoglycans bound to the cell-associated BMMC proteoglycans were chondroitin sulfates based upon their susceptibility to chondroitinase ABC digestion; HPLC of the chondroitinase ABC- generated unsaturated disaccharides revealed these glycosaminoglycans to be chondroitin sulfate E. As determined by heparinase and nitrous acid degradations, approximately 10% of the glycosaminoglycans bound to BMMC proteoglycans were heparin. In contrast, mast cells recovered from the peritoneal cavity of congenitally mast cell-deficient WBB6F1-W/Wv mice 15 wk after intraperitoneal injection of BMMC synthesized approximately 650,000 Mr protease-resistant proteoglycans that contained approximately 80% heparin glycosaminoglycans of approximately 105,000 Mr. Thus, after adoptive transfer, the SMC of the previously mast cell-deficient mice were like those recovered from the normal WBB6F1-+/+ mice that were shown to synthesize approximately 600,000 Mr proteoglycans that contained approximately 80% heparin glycosaminoglycans of approximately 115,000 Mr. As assessed by indirect immunofluorescence staining and flow cytometry using the B1.1 rat mAb (an antibody that recognizes an epitope located on the neutral glycosphingolipid globopentaosylceramide), approximately 5% of BMMC bound the antibody detectably, whereas approximately 72% of the SMC that were harvested from mast cell-deficient mice 15 wk after adoptive transfer of BMMC were B1.1-positive

  1. Involvement of mast cells and histamine in edema induced in mice by Scolopendra viridicornis centipede venom.

    PubMed

    Távora, Bianca C L F; Kimura, Louise F; Antoniazzi, Marta M; Chiariello, Thiago M; Faquim-Mauro, Eliana L; Barbaro, Katia C

    2016-10-01

    Bites caused by Scolopendra viridicornis centipede are mainly characterized by burning pain, paresthesia and edema. On this regard, the aim of this work was to study the involvement of mast cells and histamine in edema induced by Scolopendra viridicornis (Sv) centipede venom. The edema was analyzed on mice paws. The mice were pretreated with cromolyn (mast cell degranulation inhibitor) and antagonists of histamine receptors, such as promethazine (H1R), cimetidine (H2R) and thioperamide (H3/H4R). The analyses were carried out at different times after the injection of Sv venom (15 μg) or PBS in the footpad of mice. Our results showed a significant inhibition of the edema induced by Sv venom injection in mice previously treated: cromolyn (38-91%), promethazine (50-59%) and thioperamide (around 30%). The treatment with cimetidine did not alter the edema induced by Sv venom. Histopathological analysis showed that Sv venom injection (15 μg) induced edema, leukocyte recruitment and mast cells degranulation, when compared with the PBS-injected mice. Direct effects of the Sv venom on mast cells were studied in PT-18 line (mouse mast cell) and RBL-2H3 cells (rat mast cells). The data showed that higher doses (3.8 and 7.5 μg) of Sv venom were cytotoxic for both cell lineages and induced morphological changes. However, lower doses of the venom induced degranulation of both mast cell lines, as well as the secretion of MCP-1, IL-6 and IL-1β. The production of PGD2 was only observed in the RBL-2H3 line incubated with Sv venom. Taking our results together, we demonstrated that upon Sv venom exposure, mast cells and histamine are crucial for the establishment of the local inflammatory reaction.

  2. Mast material test program (MAMATEP)

    NASA Technical Reports Server (NTRS)

    Ciancone, Michael L.; Rutledge, Sharon K.

    1988-01-01

    The Mast Material Test Program (MAMATEP) at NASA Lewis is discussed. Objectives include verifying the need for, and evaluating the performance of, various protection techniques for the Solar Array Assembly mast of the Space Station Photovoltaic Power Module. Mast material samples were evaluated in terms of mass and bending modulus, measured before and after environmental exposure. Test environments included atomic oxygen exposure (RF plasma asher), thermal cycling, and mechanical flexing. Protective coatings included CV-1144 silicon, a Ni/Au/InSn eutectic, and an open weave, Al braid. Results indicate that unprotected samples degrade in an atomic oxygen environment at a steady rate. Open weave, Al braid offers little protection for the fiberglass-epoxy sample in an asher environment. Ni/Au/InSn eutectic offers excellent protection in an asher environment prior to thermal cycling and mechanical flexing. Long duration asher results from unprotected samples indicate that, even though the fiberglass-epoxy degrades, a protection technique may not be necessary to ensure structural integrity. However, a protection technique may be desirable to limit or contain the amount of debris generated by the degradation of the fiberglass-epoxy.

  3. Solar Array Mast Imagery Discussion for ISIW

    NASA Technical Reports Server (NTRS)

    Kilgo, Gary

    2017-01-01

    SAW Mast inspection background: In 2012, NASA's Flight Safety Office requested the Micro Meteoroid and Orbital Debris (MMOD) office determine the probability of damage to the Solar Array Wing (SAW) mast based on the exposure over the life time of the ISS program. As part of the risk mitigation of the potential MMOD strikes. ISS Program office along with the Image Science and Analysis Group (ISAG) began developing methods for imaging the structural components of the Mast.

  4. Mast cells in human health and disease.

    PubMed

    DeBruin, Erin J; Gold, Matthew; Lo, Bernard C; Snyder, Kimberly; Cait, Alissa; Lasic, Nikola; Lopez, Martin; McNagny, Kelly M; Hughes, Michael R

    2015-01-01

    Mast cells are primarily known for their role in defense against pathogens, particularly bacteria; neutralization of venom toxins; and for triggering allergic responses and anaphylaxis. In addition to these direct effector functions, activated mast cells rapidly recruit other innate and adaptive immune cells and can participate in "tuning" the immune response. In this review we touch briefly on these important functions and then focus on some of the less-appreciated roles of mast cells in human disease including cancer, autoimmune inflammation, organ transplant, and fibrosis. Although it is difficult to formally assign causal roles to mast cells in human disease, we offer a general review of data that correlate the presence and activation of mast cells with exacerbated inflammation and disease progression. Conversely, in some restricted contexts, mast cells may offer protective roles. For example, the presence of mast cells in some malignant or cardiovascular diseases is associated with favorable prognosis. In these cases, specific localization of mast cells within the tissue and whether they express chymase or tryptase (or both) are diagnostically important considerations. Finally, we review experimental animal models that imply a causal role for mast cells in disease and discuss important caveats and controversies of these findings.

  5. The role of Notch signaling in muscle progenitor cell depletion and the rapid onset of histopathology in muscular dystrophy

    PubMed Central

    Mu, Xiaodong; Tang, Ying; Lu, Aiping; Takayama, Koji; Usas, Arvydas; Wang, Bing; Weiss, Kurt; Huard, Johnny

    2015-01-01

    Although it has been speculated that stem cell depletion plays a role in the rapid progression of the muscle histopathology associated with Duchenne Muscular Dystrophy (DMD), the molecular and cellular mechanisms responsible for stem cell depletion remain poorly understood. The rapid depletion of muscle stem cells has not been observed in the dystrophin-deficient model of DMD (mdx mouse), which may explain the relatively mild dystrophic phenotype observed in this animal model. In contrast, we have observed a rapid occurrence of stem cell depletion in the dystrophin/utrophin double knockout (dKO) mouse model, which exhibits histopathological features that more closely recapitulate the phenotype observed in DMD patients compared with the mdx mouse. Notch signaling has been found to be a key regulator of stem cell self-renewal and myogenesis in normal skeletal muscle; however, little is known about the role that Notch plays in the development of the dystrophic histopathology associated with DMD. Our results revealed an over-activation of Notch in the skeletal muscles of dKO mice, which correlated with sustained inflammation, impaired muscle regeneration and the rapid depletion and senescence of the muscle progenitor cells (MPCs, i.e. Pax7+ cells). Consequently, the repression of Notch in the skeletal muscle of dKO mice delayed/reduced the depletion and senescence of MPCs, and restored the myogenesis capacity while reducing inflammation and fibrosis. We suggest that the down-regulation of Notch could represent a viable approach to reduce the dystrophic histopathologies associated with DMD. PMID:25678553

  6. The role of Notch signaling in muscle progenitor cell depletion and the rapid onset of histopathology in muscular dystrophy.

    PubMed

    Mu, Xiaodong; Tang, Ying; Lu, Aiping; Takayama, Koji; Usas, Arvydas; Wang, Bing; Weiss, Kurt; Huard, Johnny

    2015-05-15

    Although it has been speculated that stem cell depletion plays a role in the rapid progression of the muscle histopathology associated with Duchenne Muscular Dystrophy (DMD), the molecular and cellular mechanisms responsible for stem cell depletion remain poorly understood. The rapid depletion of muscle stem cells has not been observed in the dystrophin-deficient model of DMD (mdx mouse), which may explain the relatively mild dystrophic phenotype observed in this animal model. In contrast, we have observed a rapid occurrence of stem cell depletion in the dystrophin/utrophin double knockout (dKO) mouse model, which exhibits histopathological features that more closely recapitulate the phenotype observed in DMD patients compared with the mdx mouse. Notch signaling has been found to be a key regulator of stem cell self-renewal and myogenesis in normal skeletal muscle; however, little is known about the role that Notch plays in the development of the dystrophic histopathology associated with DMD. Our results revealed an over-activation of Notch in the skeletal muscles of dKO mice, which correlated with sustained inflammation, impaired muscle regeneration and the rapid depletion and senescence of the muscle progenitor cells (MPCs, i.e. Pax7+ cells). Consequently, the repression of Notch in the skeletal muscle of dKO mice delayed/reduced the depletion and senescence of MPCs, and restored the myogenesis capacity while reducing inflammation and fibrosis. We suggest that the down-regulation of Notch could represent a viable approach to reduce the dystrophic histopathologies associated with DMD.

  7. Selective Cannabinoid Receptor-1 Agonists Regulate Mast Cell Activation in an Oxazolone-Induced Atopic Dermatitis Model

    PubMed Central

    Nam, Gaewon; Jeong, Se Kyoo; Park, Bu Man; Lee, Sin Hee; Kim, Hyun Jong; Hong, Seung-Phil; Kim, Beomjoon

    2016-01-01

    Background Many inflammatory mediators, including various cytokines (e.g. interleukins and tumor necrosis factor [TNF]), inflammatory proteases, and histamine are released following mast cell activation. However, the endogenous modulators for mast cell activation and the underlying mechanism have yet to be elucidated. Endogenous cannabinoids such as palmitoylethanolamide (PEA) and N-arachidonoylethanolamine (anandamide or AEA), were found in peripheral tissues and have been proposed to possess autacoid activity, implying that cannabinoids may downregulate mast cell activation and local inflammation. Objective In order to investigate the effect of cannabinoid receptor-1 (CB1R) agonists on mast cell activation, AEA-derived compounds were newly synthesized and evaluated for their effect on mast cell activation. Methods The effects of selected compounds on FcεRI-induced histamine and β-hexosaminidase release were evaluated in a rat basophilic leukemia cell line (RBL-2H3). To further investigate the inhibitory effects of CB1R agonist in vivo, an oxazolone-induced atopic dermatitis mouse model was exploited. Results We found that CB1R inhibited the release of inflammatory mediators without causing cytotoxicity in RBL-2H3 cells and that CB1R agonists markedly and dose-dependently suppressed mast cell proliferation indicating that CB1R plays an important role in modulating antigen-dependent immunoglobulin E (IgE)-mediated mast cell activation. We also found that topical application of CB1R agonists suppressed the recruitment of mast cells into the skin and reduced the level of blood histamine. Conclusion Our results indicate that CB1R agonists down-regulate mast cell activation and may be used for relieving inflammatory symptoms mediated by mast cell activation, such as atopic dermatitis, psoriasis, and contact dermatitis. PMID:26848215

  8. Anaphylatoxin C3a induced mediator release from mast cells

    SciTech Connect

    Herrscher, R.; Hugli, T.E.; Sullivan, T.J.

    1986-03-01

    The authors investigated the biochemical and functional consequences of the binding of highly purified human C3a to isolated rat serosal mast cells. C3a caused a dose-dependent (1-30 ..mu..M), noncytotoxic release of up to 64% (+/- 7 SEM) of the mast cell histamine content. C3a (10..mu..M) increased /sup 45/Ca/sup + +/ uptake 8.2- fold (+/- 2.2 SEM) above unstimulated control values within 10 minutes. Arachidonyl-diacylglycerol and arachidonyl-monoacylglycerol levels increased significantly within 2 minutes after C3a (10 ..mu..M) stimulation. Turnover of phosphatidylinositol, phosphatidic acid, and phosphatidylcholine were increased within 15 minutes. In contrast to antigen, C3a stimulation (10 ..mu..M) was not enhanced by exogenous phosphatidylserine, and was not inhibited by ethanol (100 ..mu..mM). C3a suppressed arachidonic acid (AA) release to 38% (+/- 9 SEM) below baseline, and did not cause PGD/sub 2/ formation. C3a and the desarginine form of C3a caused identical responses in all experiments. These studies indicate that C3a stimulation activates mast cell preformed mediator release in a manner very similar to antigen-IgE stimulation, but C3a suppresses free AA levels and does not stimulate PGD/sub 2/ synthesis.

  9. Further characterization of protein kinase C in mouse mast cells

    SciTech Connect

    White, J.R.; Ishizaka, T.

    1986-03-01

    Bridging of cell-bound IgE antibody molecules on colony stimulating factor dependent mouse mast cell line (PT-18) cells by multivalent antigen induces the mobilization and uptake of Ca/sup 2 +/ monitored by Quin-2 and the production of diacylglycerol. Exposure of the sensitized cells to antigen also induces a substantial increase in protein kinase C (PKC) activity in the plasma membrane (340 units to 1375 units: 1 unit = 1 pmol of /sup 32/P incorporated into Histone H-1/min/10/sup 7/ cells), within 30 seconds. There is also an increase in /sup 3/H phorbol-12, 13-dibutyrate (/sup 3/H-PDB) binding which parallels the increase in PKC activity both in kinetics and antigen dose dependency. Determination of K/sub m/ and V/sub max/ for PKC revealed no difference between the cytosolic and membranous forms of PKC. Partial purification of PKC from the membrane of sensitized mast cells which had been labeled with /sup 32/P and stimulated with DNP-HSA revealed a protein of 80-84,000 molecular weight, which migrated on polyacrylamide gel electrophoresis just above an authentic standard of PKC purified from rat brain. Treatment of the PKC from mouse mast cell membrane with alkaline phosphatase resulted in a reduction of phosphorylating activity and bindability of /sup 3/H-PDB. In conclusion, the authors speculate that activation of mouse mast cells by cross-linking IgE results in the phosphorylation of a silent-pool of PKC converting it from an inactive state to an activated form.

  10. Effects of Toxin A from Clostridium difficile on Mast Cell Activation and Survival

    PubMed Central

    Calderón, Gloria M.; Torres-López, Javier; Lin, Tong-Jun; Chavez, Bibiana; Hernández, Manuel; Muñoz, Onofre; Befus, A. Dean; Enciso, J. Antonio

    1998-01-01

    Toxins A and B from Clostridium difficile are the main cause of antibiotic-associated diarrhea and pseudomembranous colitis. They cause fluid accumulation, necrosis, and a strong inflammatory response when inoculated in intestinal loops. Since mast cells are a rich source of inflammatory mediators, abundant in the gut, and known to be involved in C. difficile-induced enteritis, we studied the in vitro effect of toxin A on isolated mast cells. Normal rats sensitized by infection with Nippostrongilus brasiliensis were used to isolate peritoneal mast cells (PMC). PMC from naive rats were stimulated with calcium ionophore A23187 as a model of antigen-independent activation, and PMC from sensitized rats were stimulated with N. brasiliensis antigens to study immunoglobulin E-dependent mast cell activation. After 4 h, toxin A did not induce release of nitric oxide or histamine in naive PMC. However, 10 ng of toxin per ml caused a significant release of tumor necrosis factor alpha (TNF-α). In contrast, 1 μg of toxin per ml inhibited antigen or A23187-induced histamine release by PMC. Toxin A at 1 μg/ml for 4 h caused disruption of actin which aggregated in the cytoplasm and around the nucleus. After 24 h, chromatin condensation, cytoplasmic blebbing, and apoptotic-like vesicles were observed; DNA fragmentation was documented also. These results suggest that mast cells may participate in the initial inflammatory response to C. difficile infection by releasing TNF-α upon interaction with toxin A. However, longer exposure to toxin A affects the release of inflammatory mediators, perhaps because of the alteration of the cytoskeleton and induction of apoptosis. The impaired functions and survival of mast cells by C. difficile toxin A could hamper the capacity of these cells to counteract the infection, thus prolonging the pathogenic effects of C. difficile toxins. PMID:9596744

  11. Stem cell expansion during carcinogenesis in stem cell-depleted conditional telomeric repeat factor 2 null mutant mice.

    PubMed

    Bojovic, B; Ho, H-Y; Wu, J; Crowe, D L

    2013-10-24

    To examine the role of telomeric repeat-binding factor 2 (TRF2) in epithelial tumorigenesis, we characterized conditional loss of TRF2 expression in the basal layer of mouse epidermis. These mice exhibit some characteristics of dyskeratosis congenita, a human stem cell depletion syndrome caused by telomere dysfunction. The epidermis in conditional TRF2 null mice exhibited DNA damage response and apoptosis, which correlated with stem cell depletion. The stem cell population in conditional TRF2 null epidermis exhibited shorter telomeres than those in control mice. Squamous cell carcinomas induced in conditional TRF2 null mice developed with increased latency and slower growth due to reduced numbers of proliferating cells as the result of increased apoptosis. TRF2 null epidermal stem cells were found in both primary and metastatic tumors. Despite the low-grade phenotype of the conditional TRF2 null primary tumors, the number of metastatic lesions was similar to control cancers. Basal cells from TRF2 null tumors demonstrated extreme telomere shortening and dramatically increased numbers of telomeric signals by fluorescence in situ hybridization due to increased genomic instability and aneuploidy in these cancers. DNA damage response signals were detected at telomeres in TRF2 null tumor cells from these mice. The increased genomic instability in these tumors correlated with eightfold expansion of the transformed stem cell population compared with that in control cancers. We concluded that genomic instability resulting from loss of TRF2 expression provides biological advantages to the cancer stem cell population.

  12. Are mast cells important in diabetes?

    PubMed

    Kempuraj, Duraisamy; Caraffa, Alessandro; Ronconi, Gianpaolo; Lessiani, Gianfranco; Conti, Pio

    2016-01-01

    Diabetes is a metabolic disorder characterized by hyperglycemia and associated with microvascular and macrovascular syndromes mediated by mast cells. Mast cells are activated through cross-linking of their surface high affinity receptors for IgE (FcRI) or other antigens, leading to degranulation and release of stored inflammatory mediators, and cytokines/chemokines without degranulation. Mast cells are implicated in innate and acquired immunity, inflammation and metabolic disorders such as diabetes. Histamine and tryptase genes in mast cells are overexpressed in pancreatic tissue of type 2 diabetes mellitus (T2DM) patients. Histamine is a classic inflammatory mediator generated by activated receptors of mast cells from the histamine-forming enzyme histidine decarboxylase (HDC), which can be activated by two inflammatory chemokines, RANTES and MPC1, when injected intramuscularly or intradermally in mice. This activation is inhibited in genetically mast cell-deficient W/Wv mice, which show higher insulin sensitivity and glucose tolerance. This study contributes to understanding the mechanism by which mast cells profoundly affect diabetes, and their manipulation could represent a new therapeutic strategy. However, further studies are needed to clarify the role of mast cells in inflammation and metabolic disorders such as diabetes.

  13. Mast cells in nonmammalian vertebrates: an overview.

    PubMed

    Baccari, Gabriella Chieffi; Pinelli, Claudia; Santillo, Alessandra; Minucci, Sergio; Rastogi, Rakesh Kumar

    2011-01-01

    Mast cells are best known as multifunctional entities that may confer a benefit on immune system. This review presents the known facts on mast-cell system and breakthroughs in mast-cell biology in fish, amphibians, reptiles, and birds. As compared to mammals, there are relatively few data available on mast cells in many nonmammalian vertebrates. Nevertheless, like in mammals, mast cells in nonmammalian vertebrates contain a wide range of bioactive compounds including histamine, heparin, neuropeptides, and neutral proteases. In bony fishes, these cells secrete antimicrobial peptides as well. Mast cells have a widespread distribution in the brain, endocrine glands, intestine, liver, kidney, skin, tongue, and lungs, the highest concentration occurring in different tissues in the different taxa. Currently, researchers are grappling with the nature of scientific support to substantiate the functional importance of mast cells in nonmammalian vertebrates. Ultimately, the origin and evolution of vertebrate mast cell is of great interest to comparative immunologists seeking an underlying trend in the phylogenetic development of immunity.

  14. [Mast cells and basophils and their disorders].

    PubMed

    Bösiger, J; Fehr, J

    2006-01-01

    This short review gives a brief overview on recent findings about the roles of basophils and mast cells in acquired and innate immunity. We try to give some insight into the methods used to study physiologic functions of mast cells and basophils. We mention variations of circulating basophil numbers as an epiphenomenon of some internal diseases and present an update on mastocytosis.

  15. Identification of chondroitin sulfate E proteoglycans and heparin proteoglycans in the secretory granules of human lung mast cells.

    PubMed Central

    Stevens, R L; Fox, C C; Lichtenstein, L M; Austen, K F

    1988-01-01

    The predominant subclasses of mast cells in both the rat and the mouse can be distinguished from one another by their preferential synthesis of 35S-labeled proteoglycans that contain either heparin or oversulfated chondroitin sulfate glycosaminoglycans. Although [35S]heparin proteoglycans have been isolated from human lung mast cells of 40-70% purity and from a skin biopsy specimen of a patient with urticaria pigmentosa, no highly sulfated chondroitin sulfate proteoglycan has been isolated from any enriched or highly purified population of human mast cells. We here demonstrate that human lung mast cells of 96% purity incorporate [35S] sulfate into separate heparin and chondroitin sulfate proteoglycans in an approximately equal to 2:1 ratio. As assessed by HPLC of the chondroitinase ABC digests, the chondroitin [35S]sulfate proteoglycans isolated from these human lung mast cells contain the same unusual chondroitin sulfate E disaccharide that is present in proteoglycans produced by interleukin 3-dependent mucosal-like mouse mast cells. Both the chondroitin [35S]sulfate E proteoglycans and the [35S]heparin proteoglycans were exocytosed from the [35S]sulfate-labeled cells via perturbation of the IgE receptor, indicating that both types of 35S-labeled proteoglycans reside in the secretory granules of these human lung mast cells. PMID:3353378

  16. Identification of chondroitin sulfate E proteoglycans and heparin proteoglycans in the secretory granules of human lung mast cells

    SciTech Connect

    Stevens, R.L.; Austen, K.F. ); Fox, C.C.; Lichtenstein, L.M. )

    1988-04-01

    The predominant subclasses of mast cells in both the rat and the mouse can be distinguished from one another by their preferential synthesis of {sup 35}S-labeled proteoglycans that contain either heparin or oversulfated chondroitin sulfate glycosaminoglycans. Although ({sup 35}S)heparin proteoglycans have been isolated from human lung mast cells of 40-70% purity and from a skin biopsy specimen of a patient with urticaria pigmentosa, no highly sulfated chondroitin sulfate proteoglycan has been isolated from any enriched or highly purified population of human mast cells. The authors demonstrate that human lung mast cells of 96% purity incorporate ({sup 35}S)sulfate into separate heparin and chondroitin sulfate proteoglycans in an {approx}2:1 ratio. As assessed by HPLC of the chondroitinase ABC digests, the chondroitin ({sup 35}S)sulfate proteoglycans isolated from these human lung mast cells contain the same unusual chondroitin sulfate E disaccharide that is present in proteoglycans produced by interleukin 3-dependent mucosal-like mouse mast cells. Both the chondroitin ({sup 35}S)sulfate E proteoglycans and the ({sup 35}S)heparin proteoglycans were exocytosed from the ({sup 35}S)sulfate-labeled cells via perturbation of the IgE receptor, indicating that both types of {sup 35}S-labeled proteoglycans reside in the secretory granules of these human lung mast cells.

  17. Radioprotective effect of kupffer cell depletion on hepatic sinusoidal endothelial cells.

    PubMed

    Chen, Yi-Xing; Zeng, Zhao-Chong; Sun, Jing; Zhang, Zhen-Yu; Zeng, Hai-Ying; Hu, Wei-Xu

    2015-05-01

    Radiation-induced liver injury remains a clinical problem and data suggest that sinusoidal endothelial cells (SECs) are an important target. The purpose of this study was to determine whether the inhibition of Kupffer cells before exposure would protect SECs from radiation-induced injury. Sprague-Dawley rats were intravenously injected 24 h before irradiation with Kupffer cell inhibitor gadolinium chloride (GdCl3) (10 mg/kg body weight). Three groups of animals were treated: 1. control group (saline and sham irradiation); 2. GdCl3 + 30 Gy radiation group and 3. 30 Gy radiation only group. Specimens were collected at 2, 6, 12, 24 and 48 h after completion of each treatment. Liver tissue was assessed for inflammatory cytokine expression and radiation-induced SEC injury based on serum hyaluronic acid (HA) level, apoptosis and ultrastructural and histological analyses. The results showed that radiation exposure caused apoptosis of SECs, but not hepatocytes. Inflammatory cytokine expression, including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) expression, was significantly attenuated in the GdCl3 + 30 Gy radiation group, compared with the 30 Gy radiation-only group (P < 0.05). The GdCl3 + radiation-treated rats exhibited significantly lower levels of HA and SEC apoptosis than the radiation-treated only rats at early time points, and radiation-induced liver injury was also attenuated. In conclusion, we hypothesize that selective Kupffer cell inhibition by gadolinium chloride was shown to reduce apoptosis in SECs caused by irradiation of the live and protected the liver against radiation-induced injury.

  18. Marshall Avionics Testbed System (MAST)

    NASA Technical Reports Server (NTRS)

    Smith, Wayne D.

    1989-01-01

    Work accomplished in the summer of 1989 in association with the NASA/ASEE Summer Faculty Research Fellowship Program at Marshall Space Flight Center is summarized. The project was aimed at developing detailed specifications for the Marshall Avionics System Testbed (MAST). This activity was to include the definition of the testbed requirements and the development of specifications for a set of standard network nodes for connecting the testbed to a variety of networks. The project was also to include developing a timetable for the design, implementation, programming and testing of the testbed. Specifications of both hardware and software components for the system were to be included.

  19. Mast cell biology: introduction and overview.

    PubMed

    Gilfillan, Alasdair M; Austin, Sarah J; Metcalfe, Dean D

    2011-01-01

    In recent years, the field of mast cell biology has expanded well beyond the boundaries of atopic disorders and anaphy laxis, on which it has been historically focused. The biochemical and signaling events responsible for the development and regulation of mast cells has been increasingly studied, aided in large part by novel breakthroughs in laboratory techniques used to study these cells. The result of these studies has been a more comprehensive definition of mast cells that includes added insights to their overall biology as well as the various disease states that can now be traced to defects in mast cells. This introductory chapter outlines and highlights the various topics of mast cell biology that will be discussed in further detail in subsequent chapters.

  20. Ion channels regulating mast cell biology.

    PubMed

    Ashmole, I; Bradding, P

    2013-05-01

    Mast cells play a central role in the pathophysiology of asthma and related allergic conditions. Mast cell activation leads to the degranulation of preformed mediators such as histamine and the secretion of newly synthesised proinflammatory mediators such as leukotrienes and cytokines. Excess release of these mediators contributes to allergic disease states. An influx of extracellular Ca2+ is essential for mast cell mediator release. From the Ca2+ channels that mediate this influx, to the K+ , Cl- and transient receptor potential channels that set the cell membrane potential and regulate Ca2+ influx, ion channels play a critical role in mast cell biology. In this review we provide an overview of our current knowledge of ion channel expression and function in mast cells with an emphasis on how channels interact to regulate Ca2+ signalling.

  1. Mast cells promote melanoma colonization of lungs.

    PubMed

    Öhrvik, Helena; Grujic, Mirjana; Waern, Ida; Gustafson, Ann-Marie; Ernst, Nancy; Roers, Axel; Hartmann, Karin; Pejler, Gunnar

    2016-10-18

    Mast cells have been implicated in malignant processes, mainly through clinical correlative studies and by experiments performed using animals lacking mast cells due to defective c-kit signaling. However, mast cell-deficient mouse models based on c-kit defects have recently been questioned for their relevance. Here we addressed the effect of mast cells in a tumor setting by using transgenic Mcpt5-Cre+ R-DTA+ mice, in which the deficiency of mast cells is independent of c-kit defects. Melanoma cells (B16.F10) were administered either subcutaneously or intravenously into Mcpt5-Cre+ R-DTA+ mice or Mcpt5-Cre- R-DTA+ littermate controls, followed by the assessment of formed tumors. In the subcutaneous model, mast cells were abundant in the tumor stroma of control mice but were absent in Mcpt5-Cre+ R-DTA+ mice. However, the absence of mast cells did not affect tumor size. In contrast, after intravenous administration of B16.F10 cells, melanoma colonization of the lungs was markedly reduced in Mcpt5-Cre+ R-DTA+ vs. Mcpt5-Cre- R-DTA+ animals. Decreased melanoma colonization of the lungs in Mcpt5-Cre+ R-DTA+ animals was accompanied by increased inflammatory cell recruitment into the bronchoalveolar lavage fluid, suggesting that mast cells suppress inflammation in this setting. Further, qPCR analysis revealed significant alterations in the expression of Twist and E-cadherin in lungs of Mcpt5-Cre+ R-DTA+ vs. control Mcpt5-Cre- R-DTA+ animals, suggesting an impact of mast cells on epithelial-mesenchymal transition. In conclusion, this study reveals that mast cells promote melanoma colonization of the lung.

  2. The human mast cell: an overview.

    PubMed

    Krishnaswamy, Guha; Ajitawi, Omar; Chi, David S

    2006-01-01

    Mast cells are fascinating, multifunctional, tissue-dwelling cells that have been traditionally associated with the allergic response. However, recent studies suggest these cells may be capable of regulating inflammation, host defense, and innate immunity. The purpose of this review is to present salient aspects of mast cell biology in the context of mast cell function in physiology and disease. After their development from bone marrow-derived progenitor cells that are primed with stem cell factor, mast cells continue their maturation and differentiation in peripheral tissue, developing into two well-described subsets of cells, MC(T) and MC(TC) cells. These cells can be distinguished on the basis of their tissue location, dependence on T lymphocytes, and their granule contents. Mast cells can undergo activation by antigens/allergens, superoxides, complement proteins, neuropeptides, and lipoproteins. After activation, mast cells express histamine, leukotrienes, and prostanoids, as well as proteases, and many cytokines and chemokines. These mediators may be pivotal to the genesis of an inflammatory response. By virtue of their location and mediator expression, mast cells may play an active role in many diseases, such as allergy, parasitic diseases, atherosclerosis, malignancy, asthma, pulmonary fibrosis, and arthritis. Recent data also suggest that mast cells play a vital role in host defense against pathogens by elaboration of tumor necrosis factor alpha. Mast cells also express the Toll-like receptor, which may further accentuate their role in the immune-inflammatory response. This chapter summarizes the many well-known and novel functional aspects of human mast cell biology and emphasizes their unique role in the inflammatory response.

  3. The role of Lin28b in myeloid and mast cell differentiation and mast cell malignancy

    PubMed Central

    Wang, Leo D.; Rao, Tata Nageswara; Rowe, R. Grant; Nguyen, Phi T.; Sullivan, Jessica L.; Pearson, Daniel S.; Doulatov, Sergei; Wu, Linwei; Lindsley, R. Coleman; Zhu, Hao; DeAngelo, Daniel J.; Daley, George Q.; Wagers, Amy J.

    2015-01-01

    Mast cells are critical components of the innate immune system and important for host defense, allergy, autoimmunity, tissue regeneration, and tumor progression. Dysregulated mast cell development leads to systemic mastocytosis, a clinically variable but often devastating family of hematologic disorders. Here we report that induced expression of Lin28, a heterochronic gene and pluripotency factor implicated in driving a fetal hematopoietic program, caused mast cell accumulation in adult mice in target organs such as the skin and peritoneal cavity. In vitro assays revealed a skewing of myeloid commitment in LIN28B-expressing hematopoietic progenitors, with increased levels of LIN28B in common myeloid and basophil-mast cell progenitors altering gene expression patterns to favor cell fate choices that enhanced mast cell specification. In addition, LIN28B-induced mast cells appeared phenotypically and functionally immature, and in vitro assays suggested a slowing of mast cell terminal differentiation in the context of LIN28B upregulation. Finally, interrogation of human mast cell leukemia samples revealed upregulation of LIN28B in abnormal mast cells from patients with systemic mastocytosis (SM). This work identifies Lin28 as a novel regulator of innate immune function and a new protein of interest in mast cell disease. PMID:25655194

  4. Mast cell tryptase and asthma

    PubMed Central

    Timmerman, H.

    1997-01-01

    Recent physiological and pharmacological studies have indicated the potential importance of tryptase, the major protein component in mast cells, in inflammatory diseases (especially asthma). Being released at inflammatory sites after the activation of mast cells, tryptase is capable of causing bronchohyperresponsiveness and infiltration of eosinophils, neutrophils, etc. in animal airways. The mechanisms by which tryptase causes bronchoconstriction involve probably the potentiation of other chemical mediators such as histamine, production of bradykinin via the hydrolysis of kininogen, and cleavage of the bronchodilating peptides VIP (vasoactive intestinal peptide) and PHM (peptide histidine-methionine). Tryptase has also been found to be a potent mitogen in vitro for airway smooth muscle cells and epithelial cells, implying its role in the hyperplasia of the asthmatic airways. The experimental data providing evidence for the above roles of tryptase are summarized in the present review, as well as the effects of tryptase inhibition in animal asthma models. The potential strategies for the development of anti-asthmatic agents based on the inhibition of tryptase are discussed. PMID:18472864

  5. Passive cutaneous anaphylaxis inhibition: evidence for heterogeneity in IgE mast cell interaction.

    PubMed Central

    Lehrer, S B; McCants, M L; Farris, P N; Bazin, H

    1981-01-01

    Recent evidence suggests that IgE molecules are heterogeneous with respect to ability to compete with IgE myeloma for sensitization of histamine release from chopped human lung and ability to passively sensitize human basophils for antigen-induced histamine release. These observations prompted further investigation of the possibility that there exists a functional heterogeneity in the IgE molecules with respect to mast-cell binding properties. Using eight different purified rat IgE myeloma proteins, we found that they differ in their ability to inhibit the passive cutaneous anaphylaxis (PCA) reaction of mouse reaginic antisera. This suggests that IgE molecules differ in their ability to bind to mast cell receptors. Since maximal inhibition of different mouse reaginic antisera and mouse IgE hybridomas is achieved with different IgE myelomas, there may exist a functional heterogeneity in mast-cell binding receptors as well. PMID:7319556

  6. Aspergillus oryzae lectin induces anaphylactoid oedema and mast cell activation through its interaction with fucose of mast cell-bound non-specific IgE.

    PubMed

    Yamaki, K; Yoshino, S

    2011-11-01

    We investigated whether Aspergillus oryzae lectin (AOL), a fucose-specific lectin, induces anaphylactoid reactions and mast cell activation. The injection of AOL into footpads of mice produced a dose-related acute paw oedema. The AOL-induced oedema was attenuated by predose of histamine H1 receptor blocker or pretreatment of the lectin with fucose before injection and was not observed in SCID and mast cell-deficient WBB6F1-W/Wv mice. These results suggested that the AOL-induced anaphylactoid reaction was mediated by histamine released from mast cells. In addition, the activation of mast cells was seemed to be induced by the crosslinking of IgE on the cell surface following the binding of AOL to fucose residues in IgE. Consistent with the in vivo results, AOL induced the degranulation of the rat mast cell line RBL2H3 sensitized with monoclonal IgE. As AOL induced the increase in intracellular Ca(2+) concentration of IgE-sensitized RBL2H3 cells as well as antigen stimulation, AOL could input signals from FcεRI. The degranulation of IgE-sensitized RBL2H3 cells by AOL was diminished by pretreatment of AOL with fucose. Defucosylated IgE did not induce degranulation of RBL2H3 cells in response to AOL stimulation, in spite of its ability to induce degranulation by antigen stimulation as intact IgE. These results indicated that AOL bound to fucose residue of IgE causing antigen-independent IgE-mediated mast cell activation and anaphylactoid reactions in vitro and in vivo, respectively. AOL bound to human IgE as well as to mouse IgE, suggesting the possible implication of AOL in the allergic response to Aspergillus oryzae in humans.

  7. Mast cells modulate the inflammatory process in endotoxin-induced uveitis

    PubMed Central

    Sebastião da Silva, Pierre; Girol, Ana Paula

    2011-01-01

    Purpose To investigate the role of mast cells and annexin-A1 (Anxa1) in endotoxin-induced uveitis (EIU). Methods EIU was induced by injection of lipopolysaccharide (LPS) into the paws of rats, which were then sacrificed after 24 and 48 h. To assess EIU in the absence of mast cells, groups of animals were pretreated with compound 48/80 (c48/80) and sacrificed after 24 h after no treatment or EIU induction. The eyes were used for histological studies and the aqueous humor (AqH) pool was used for the analysis of transmigrated cells and Anxa1 levels. In inflammatory cells, Anxa1 expression was monitored by immunohistochemistry. Results After 24 h, rats with EIU exhibited degranulated mast cells, associated with elevated numbers of infiltrating leukocytes and the high expression of Anxa1 in the AqH and the neutrophils. After 48 h of EIU, the mast cells were intact, indicating granule re-synthesis, and there was a reduction of neutrophil transmigration and an increase in the number of mononuclear phagocytic cells in ocular tissues. Anxa1 expression was decreased in neutrophils but increased in mononuclear phagocytic cells. In the animals pretreated with c48/80 and subjected to EIU, mast cells responded to this secretagogue by degranulating and few transmigrated neutrophils were observed. Conclustions We report that mast cells are a potential source of pharmacological mediators that are strongly linked to the pathophysiology of EIU, and the endogenous protein Anxa1 is a mediator in the homeostasis of the inflammatory process with anti-migratory effects on leukocytes, which supports further studies of this protein as an innovative therapy for uveitis. PMID:21633711

  8. Effect of Omegaven on mast cell concentration in diabetic wound healing.

    PubMed

    Babaei, Saeid; Ansarihadipour, Hadi; Nakhaei, Mahmoodreza; Darabi, Mohammadreza; Bayat, Parvindokht; Sakhaei, Mohammadhassan; Baazm, Maryam; Mohammadhoseiny, Atefe

    2016-12-09

    Diabetic wound healing is a complicated process. In all over the world 15% of 200 million diabetic people suffer from diabetic foot problems. Mast cells are known to participate in three phases of wound healing: the inflammatory reaction, angiogenesis and extracellular-matrix reabsorption. The inflammatory reaction is mediated by released histamine and arachidonic acid metabolites. Omega-3 fatty acids alter proinflammatory cytokine production during wound healing which affects the presence of inflammatory cells in wound area as well, but how this events specifically influences the presence of mast cells in wound healing is not clearly understood. This study is conducted to determine the effect of Omegaven, eicosapentaenoic (EPA) and docosahexaenoic (DHA) on pattern of presence of mast cells in diabetic wound area. Diabetic male wistar rats were euthanized at 1, 3, 5, 7 and 15 days after the excision was made. To estimate the number of mast cells histological sections were provided from wound area and stained with toluidine blue. In this relation wound area (8400 microscopic field, 45.69 mm(2)) were examined by stereological methods by light microscope. We found that comparing experimental and control group, omega-3 fatty acids significantly decreased wound area in day 7 and also the number of grade three mast cells in day 3 and 5. We also found that wound strength has significantly increased in experimental group at day 15.

  9. Effect of fruits of Opuntia elatior Mill on mast cell degranulation

    PubMed Central

    Chauhan, Sanjay P.; Sheth, N. R.; Suhagia, B. N.

    2015-01-01

    Background: The presence of potentially active nutrients and their multifunctional properties make prickly pear a perfect candidate for the production of phytopharmaceutical products. Among the numerous Opuntia species, bioactive compounds have been isolated and characterized primarily from Opuntia ficus-indica, Opuntia polycantha, Opuntia stricta, Opuntia dilleni for various medicinal properties. Objective: Based on the traditional use of prickly pear for enhancement of immune function, the objective of the present study to evaluate the effect of prickly pear on mast cell degranulation function. Materials and Methods: The Opuntia fruit juice (OFJ) (10-200 μl/ml) were studied for the effect on sensitized rat peritoneal mast cell degranulation induced by immunological (egg albumin), and nonimmunological (compound 48/80) stimuli and compared with that of the reference standard, sodium cromoglycate and ketotifen (10 μg/ml). Results and Conclusion: The OFJ exhibited significantly (P < 0.001) concentration dependent inhibition of mast cell degranulation. The IC50 value of OFJ was found 12.24 and 18 μl/ml for immunological and nonimmunological induced mast cell degranulation, respectively. The betacyanin is an active principle compound in prickly pear that may responsible for mast cell stabilizing action. PMID:25883521

  10. Mast cell secretome: Soluble and vesicular components.

    PubMed

    Vukman, Krisztina V; Försönits, András; Oszvald, Ádám; Tóth, Eszter Á; Buzás, Edit I

    2017-02-09

    Mast cells are multifunctional master cells implicated in both innate and adaptive immune responses. Their role has been best characterized in allergy and anaphylaxis; however, emerging evidences support their contribution to a wide variety of human diseases. Mast cells, being capable of both degranulation and subsequent recovery, have recently attracted substantial attention as also being rich sources of secreted extracellular vesicles (including exosomes and microvesicles). Along with secreted de novo synthesized soluble molecules and secreted preformed granules, the membrane-enclosed extracellular vesicles represent a previously unexplored part of the mast cell secretome. In this review article we summarize available data regarding the different soluble molecules and membrane-enclosed structures secreted by mast cells. Furthermore, we provide an overview of the release mechanisms including degranulation, piecemeal degranulation, transgranulation, and secretion of different types of extracellular vesicles. Finally, we aim to give a summary of the known biological functions associated with the different mast cell-derived secretion products. The increasingly recognized complexity of mast cell secretome may provide important novel clues to processes by which mast cells contribute to the development of different pathologies and are capable of orchestrating immune responses both in health and disease.

  11. The Mast Cell-IgE Paradox

    PubMed Central

    Galli, Stephen J.

    2017-01-01

    Mast cells and IgE are so inextricably linked to the pathology of allergic disorders, including fatal anaphylaxis, that it can be difficult to think of them in other contexts. Surely, we do not have mast cells and IgE so that we can eat a peanut and die! It is thought that mast cells and IgE and basophils (circulating granulocytes, whose functions partially overlap with those of mast cells) can contribute to host defense as components of adaptive T helper cell type 2 immune responses to helminths, ticks, and certain other parasites. Accordingly, it was suggested that allergies are misdirected type 2 immune responses in which IgE antibodies are produced against any of a broad variety of apparently harmless antigens. However, components of animal venoms also can sensitize individuals to develop severe IgE-associated allergic reactions, including fatal anaphylaxis, on subsequent venom exposure. Here, I describe evidence that mast cells can enhance innate host resistance to reptile or arthropod venoms during responses to an initial exposure to such venoms and that acquired type 2 immune responses, IgE antibodies, the high-affinity IgE receptor FcεRI, and mast cells can contribute toward acquired resistance in mice to the lethal effects of honeybee or Russell's viper venom. These findings support the hypothesis that mast cells and IgE can help protect the host against noxious substances. PMID:26776074

  12. Mast cells drive mesenteric afferent signalling during acute intestinal ischaemia.

    PubMed

    Jiang, Wen; Kirkup, Anthony J; Grundy, David

    2011-08-01

    Acute intestinal ischaemia stimulates visceral afferent nerves but the mechanisms responsible for this excitation are not fully understood. Mast cells may participate in this process as they are known to signal to mesenteric afferents during intestinal anaphylaxis and contribute to early inflammation and neuronal damage in response to cerebral ischaemia. We therefore hypothesised that mast cells are early responders to acute intestinal ischaemia and their activation initiates rapid signalling to the CNS via the excitation of mesenteric afferents. Primary afferent firing was recorded from a mesenteric nerve bundle supplying a segment of jejunum in anaesthetized adult rats. Acute focal ischaemia was produced by clamping theme senteric vessels for 8 min, and reperfusion followed removal of the vessel clip. Two episodes of ischaemia–reperfusion (I–R) separated by a 30 min interval were performed. Drugs or their vehicles were administered 10 min before the 2nd I–R episode. Ischaemia caused a reproducible, intense and biphasic afferent firing that was temporally dissociated from the concomitantly triggered complex pattern of intestinal motor activity. The L-type calcium channel blocker, nifedipine, significantly attenuated this afferent firing by a mechanism independent of its action on intestinal tone. Ischaemia-induced afferent firing was also abrogated by the mast cell stabilizer, doxantrazole, and the H1 histamine receptor antagonist, pyrilamine. In contrast, the nicotinic receptor antagonist, hexamethonium, and the N-type calcium channel toxin, ω-conotoxin GVIA, each reduced the ischaemia-evoked motor inhibition but not the concurrent afferent discharge. Similarly, the cyclooxygenase inhibitor, naproxen, had no effect on the ischaemic afferent response but reduced the intestinal tone shortly from the onset of ischaemia to the early period of reperfusion. These data support a critical role for mast cell-derived histamine in the direct chemoexcitation of

  13. Haploidentical hematopoietic stem cell transplantation with a megadose T-cell-depleted graft: harnessing natural and adaptive immunity.

    PubMed

    Aversa, Franco; Martelli, Massimo F; Velardi, Andrea

    2012-12-01

    For patients with high-risk acute leukemia who do not have a matched donor or who urgently need a transplant, transplantation from a full human leukocyte antigen (HLA) haplotype mismatched family donor should be considered a viable option. Clinical trials have shown that a strategy for haploidentical transplantation based on the infusion of high numbers of T-cell-depleted hematopoietic progenitor cells and no post-transplant immunosuppression controls bi-directional T-cell alloreactivity, ie, graft rejection and graft-versus-host disease (GvHD) in patients with leukemia. Overall, event-free survival compares favorably with reports of transplants using sources of stem cells other than the matched sibling. This transplant modality has highlighted the crucial role of donor-versus-recipient natural killer cell (NK) alloreactivity in the control of leukemia relapse. Current studies are focusing on rebuilding post-transplant immunity to improve clinical outcomes.

  14. 44. VIEW OF UMBILICAL MAST AND LAUNCH PAD FROM SOUTHWEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. VIEW OF UMBILICAL MAST AND LAUNCH PAD FROM SOUTHWEST. DOORS FOR THE UMBILICAL MAST TRENCH RAISED FOR MAINTENANCE POSITION OF 10 DEGREES. LAUNCHER IS RIGHT OF MAST; RAILS PARALLEL TO MAST. CONTROL PANELS LEFT TO RIGHT: ELECTRICAL PANEL, COMMUNICATIONS PANEL, AND MAST CONTROL PANEL. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  15. B-cell depletion in SLE: clinical and trial experience with rituximab and ocrelizumab and implications for study design.

    PubMed

    Reddy, Venkat; Jayne, David; Close, David; Isenberg, David

    2013-01-01

    B cells are believed to be central to the disease process in systemic lupus erythematosus (SLE), making them a target for new therapeutic intervention. In recent years there have been many publications regarding the experience in SLE of B-cell depletion utilising rituximab, an anti-CD20 mAb that temporarily depletes B cells,reporting promising results in uncontrolled open studies and in routine clinical use. However, the two large randomised controlled trials in extra-renal lupus (EXPLORER study) and lupus nephritis (LUNAR study) failed to achieve their primary endpoints. Based on the clinical experience with rituximab this failure was somewhat unexpected and raised a number of questions and concerns, not only into the true level of benefit of B-cell depletion in a broad population but also how to test the true level of effectiveness of an investigational agent as we seek to improve the design of therapeutic trials in SLE. A better understanding of what went wrong in these trials is essential to elucidate the underlying reasons for the disparate observations noted in open studies and controlled trials. In this review, we focus on various factors that may affect the ability to accurately and confidently establish the level of treatment effect of the investigational agent, in this case rituximab, in the tw studies and explore hurdles faced in the randomised controlled trials investigating the efficacy of ocrelizumab, the humanised anti-CD20 mAb, in SLE. Further, based on the lessons learned from the clinical trials, we make suggestions that could be implemented in future clinical trial design to overcome the hurdles faced.

  16. B-cell depletion in SLE: clinical and trial experience with rituximab and ocrelizumab and implications for study design

    PubMed Central

    2013-01-01

    B cells are believed to be central to the disease process in systemic lupus erythematosus (SLE), making them a target for new therapeutic intervention. In recent years there have been many publications regarding the experience in SLE of B-cell depletion utilising rituximab, an anti-CD20 mAb that temporarily depletes B cells, reporting promising results in uncontrolled open studies and in routine clinical use. However, the two large randomised controlled trials in extra-renal lupus (EXPLORER study) and lupus nephritis (LUNAR study) failed to achieve their primary endpoints. Based on the clinical experience with rituximab this failure was somewhat unexpected and raised a number of questions and concerns, not only into the true level of benefit of B-cell depletion in a broad population but also how to test the true level of effectiveness of an investigational agent as we seek to improve the design of therapeutic trials in SLE. A better understanding of what went wrong in these trials is essential to elucidate the underlying reasons for the disparate observations noted in open studies and controlled trials. In this review, we focus on various factors that may affect the ability to accurately and confidently establish the level of treatment effect of the investigational agent, in this case rituximab, in the two studies and explore hurdles faced in the randomised controlled trials investigating the efficacy of ocrelizumab, the humanised anti-CD20 mAb, in SLE. Further, based on the lessons learned from the clinical trials, we make suggestions that could be implemented in future clinical trial design to overcome the hurdles faced. PMID:23566295

  17. Mast cell differentiation depends on T cells and granule synthesis on fibroblasts.

    PubMed Central

    Davidson, S; Mansour, A; Gallily, R; Smolarski, M; Rofolovitch, M; Ginsburg, H

    1983-01-01

    Mast cell differentiation was generated in the following three experimental situations: (i) infection of mice with Schistosoma Mansoni or with Nippostrongylus brasiliensis and growth of the lymph node cells in the presence of the corresponding helminth antigen; (ii) immunization with horse serum and growth of blood and lymph node cells in the presence of the horse serum; (iii) exposure of T-cell-depleted suspensions of lymph node cells from unimmunized mice to T-cell factor (TCF) released into medium of the young cultures of (i) and (ii). This differentiation was also obtained when lymph node cells from athymic nude mice were exposed to TCF. The cell suspensions were plated on X-irradiated fibroblast monolayers prepared from embryonic mouse skin. Screening of the suspensions before plating on the fibroblasts in culture revealed no young forms of mast cells, and none were present in culture of nude mice lymph node cells maintained without TCF. Primordial appearance of metachromatic granules generally in the golgi zone was first seen in many 'large lymphoid cells' as early as 18 hr after plating. This was followed by increase in the cytoplasm volume, increase in granule number and mitosis, ending at 10-18 days with homogeneous populations of mature mast cells. When the mesenteric lymph node cells from mice infected with the helminths were grown in the absence of fibroblasts but in the presence of the antigen, homogeneous populations of cells with extended cytoplasm, filled with unstained vacuoles developed during days 7-13. These cells did not contain histamine (or at most 0.2 microgram per 10(6) vacuolated cells). When these cells were plated on fibroblast monolayers clear granule formation in all the vacuoles was seen 2 days later. It increased progressively in size and staining intensity, until the vacuoles transformed into typical mast cell granules. By the fourth day the vacuolated cells attained the typical mast cell morphology and the histamine content greatly

  18. Fuel retention studies on MAST

    NASA Astrophysics Data System (ADS)

    Mast Team Huang, J.; Lisgo, S.; Maddison, G.

    2011-08-01

    Fuel retention has been studied on MAST using gas-balance analysis. With 8-15 min of inter-shot helium glow-discharge cleaning (4He-GDC), the wall retention fraction stays very high (>90%) during the flat-top of the plasma current, indicating this component is dominant during the discharge. Recovery of wall conditioning with 4He-GDC suggests the retention process is dominated by direct implantation of particles in shallow surface layers. The effect of 4He-GDC duration on the particle balance has also been investigated. It is shown that when there was no preceding 4He-GDC, the wall pumping capacity was reduced, causing higher plasma density and tank pressure for the next shot.

  19. Surfactant protein A (SP-A) and SP-A-derived peptide attenuate chemotaxis of mast cells induced by human β-defensin 3.

    PubMed

    Uehara, Yasuaki; Takahashi, Motoko; Murata, Masaki; Saito, Atsushi; Takamiya, Rina; Hasegawa, Yoshihiro; Kuronuma, Koji; Chiba, Hirofumi; Hashimoto, Jiro; Sawada, Norimasa; Takahashi, Hiroki; Kuroki, Yoshio; Ariki, Shigeru

    2017-02-08

    Human β-defensin 3 (hBD3) is known to be involved in mast cell activation. However, molecular mechanisms underlying the regulation of hBD3-induced mast cell activation have been poorly understood. We previously reported that SP-A and SP-A-derived peptide 01 (SAP01) regulate the function of hBD3. In this study, we focused on the effects of SP-A and SAP01 on the activation of mast cells induced by hBD3. SAP01 directly bound to hBD3. Mast cell-mediated vascular permeability and edema in hBD3 administered rat ears were decreased when injected with SP-A or SAP01. Compatible with the results in rat ear model, both SP-A and SAP01 inhibited hBD3-induced chemotaxis of mast cells in vitro. Direct interaction between SP-A or SAP01 and hBD3 seemed to be responsible for the inhibitory effects on chemotaxis. Furthermore, SAP01 attenuated hBD3-induced accumulation of mast cells and eosinophils in tracheas of the OVA-sensitized inflammatory model. SP-A might contribute to the regulation of inflammatory responses mediated by mast cells during infection.

  20. Modelling and Analysis Capabilities for Lightweight Masts

    DTIC Science & Technology

    2001-02-01

    Defence R&D Canada National Défense Defence nationale Modelling and Analysis Capabilities for Lightweight Masts T.S. Koko , D.P. Brennan, X. Luo, M.E...Modelling and Analysis Capabilities for Lightweight Masts T. S. Koko , D. P. Brennan, X. Luo, M. E. Norwood, L. Jiang, and U. O. Akpan... Koko The scientific or technical validity of this Contract Report is entirely the responsibility of the contractor and the contents do not necessarily

  1. Mast cells in allergy: innate instructors of adaptive responses.

    PubMed

    Stelekati, Erietta; Orinska, Zane; Bulfone-Paus, Silvia

    2007-01-01

    The function of mast cells as effector cells in allergy has been extensively studied. However, increasing insight into mast cell physiology has revealed new mast cell functions and has introduced mast cells as key players in the regulation of innate as well as adaptive immunity. For example, mast cells have recently been found to express Toll-like receptors (TLRs), which enable them to participate in the innate immune response against pathogens. Furthermore, mast cells have been reported to interact with B cells, dendritic cells and T cells and thereby modulate the direction of an adaptive immune response. Finally, recent documentation that mast cells express functional MHC class II and costimulatory molecules and release immunologically active exosomes, has raised the possibility that mast cells also engage in (as yet) poorly understood antigen presentation functions. In this review, we explore the hypothesis that mast cells serve as central mediators between innate and adaptive immunity, rather as pure effector cells, during allergic innate responses.

  2. Further studies on the effect of nitrogen dioxide on mast cells: The effect of the metabolite, nitrite

    SciTech Connect

    Fujimaki, Hidekazu ); Ozawa, Masashi ); Bissonnette, E.; Befus, A.D. )

    1993-05-01

    To evaluate the relationship between atmospheric nitrogen dioxide exposure and the development of allergic diseases, the effects of nitrite as a chemical product of inhaled nitrogen dioxide on mast cell functions were investigated. We have studied nitride-induced histamine release from two functionally distinct mast cell populations, namely peritoneal mast cells (PMC) and intestinal mucosal mast cells (IMMC) of Nippostrongylus brasiliensis-infected rats. High concentrations of nitrite alone (10, 20, and 50 mM) induced histamine release from IMMC, but not from PMC. Moreover, histamine release from PMC and IMMC stimulated with sensitizing antigen was significantly enhanced by pretreatment with 50 mM nitrite or nitrate. No differences in histamine release from nitrite-treated and control PMC were seen below 1 mM. To investigate the effect of nitrite on tumor cell cytotoxic activity, PMC were incubated with various concentrations of nitrite. Pretreatment with 5 and 50 mM nitrite markedly depressed tumor necrosis factor (TNF)-[alpha]-dependent natural cytotoxicity of PMC for the tumor target WEHI-164. Thus, high concentrations of nitrite enhanced mast cell histamine release, but depressed TNF-[alpha]-dependent cytotoxicity. However, low concentrations of nitrite (<1 mM) that would normally be produced by short-term atmospheric exposure to nitrogen dioxide may have no significant effects on mast cell functions. 27 refs., 3 figs., 1 tab.

  3. Donor age matters in T-cell depleted haploidentical hematopoietic stem cell transplantation in pediatric patients: Faster immune reconstitution using younger donors.

    PubMed

    González-Vicent, Marta; Molina, Blanca; Deltoro, Natalia; Sevilla, Julián; Vicario, José Luis; Castillo, Ana; Ramirez, Manuel; Díaz, Miguel Ángel

    2017-03-04

    T-cell depleted (TCD) haploidentical transplantation is increasingly used in paediatric patients with haematological malignancies and donor selection is a challenge. We conclude that a simple criterion such as donor age should be also considered in depleted haploidentical setting because faster immune reconstitution is achieved using younger donors decreasing non-relapse related mortality.

  4. Chemotherapy-induced B-cell depletion in hepatoblastoma patients undergoing ABO-incompatible living donor liver transplantation.

    PubMed

    Kanazawa, Hiroyuki; Fukuda, Akinari; Mali, Vidyadhar Padmakar; Rahayatri, Tri Hening; Hirata, Yoshihiro; Sasaki, Kengo; Uchida, Hajime; Shigeta, Takanobu; Sakamoto, Seisuke; Matsumoto, Kimikazu; Kasahara, Mureo

    2016-05-01

    LT from ABO-I donors requires preconditioning regimens to prevent postoperative catastrophic AMR. NAC for HBL is known to cause myelosuppression leading to a reduction in the number and function of lymphocytes. We investigated this chemotherapy-induced myelosuppression in HBL patients listed for LT from ABO-I donors with reference to the kinetics of B, T cells, and anti-ABO blood type isoagglutinin titers. Between 2005 and 2015, of the 319 patients who underwent LDLT at our institute, 12 were indicated for unresectable HBL. Three patients with unresectable HBL who underwent LDLT from ABO-I donors are included in this study. Immunosuppression consisted of a standard regime of tacrolimus and low-dose steroids as in ABO compatible/identical LDLT. No additional preoperative therapies for B-cell depletion were used. Absolute lymphocyte counts, lymphocyte subsets (including CD20+ B cells, CD3+CD4+ T cells and CD3+CD8+ T cells), and anti-ABO blood type isoagglutinin titers were measured before LDLT and postoperatively. The median age at diagnosis was 19 months (range, 3-31 months). The median follow-up was seven months (range, 6-15 months). The median interval from the last NAC to LDLT was 33 days (range, 25-52 days). The median interval from LDLT to adjuvant chemotherapy was 28 days (range, 22-36 days). The counts of CD20+ B cells before LDLT were depleted to median 5 cells/mm(3) (range, 0-6 cells/mm(3)). There was a transient rebound in the CD20+ B cell counts on day seven (maximum of 82 cells/mm(3)) followed by a decline starting at 14 days after LDLT that was sustained for the duration of adjuvant chemotherapy. Anti-ABO blood type isoagglutinin titers were lowered to between 1:1 and 1:16 before LDLT and remained low for the duration of follow-up in this study. All of the three patients remained in good health without either acute cellular or AMR after LDLT. The B-cell depletion that occurs after cisplatin-based chemotherapy for HBL may help accomplish safe ABO-I LDLT

  5. A Microplate Assay to Assess Chemical Effects on RBL-2H3 Mast Cell Degranulation: Effects of Triclosan without Use of an Organic Solvent

    PubMed Central

    Shim, Juyoung; Gosse, Julie A.

    2013-01-01

    Mast cells play important roles in allergic disease and immune defense against parasites. Once activated (e.g. by an allergen), they degranulate, a process that results in the exocytosis of allergic mediators. Modulation of mast cell degranulation by drugs and toxicants may have positive or adverse effects on human health. Mast cell function has been dissected in detail with the use of rat basophilic leukemia mast cells (RBL-2H3), a widely accepted model of human mucosal mast cells3-5. Mast cell granule component and the allergic mediator β-hexosaminidase, which is released linearly in tandem with histamine from mast cells6, can easily and reliably be measured through reaction with a fluorogenic substrate, yielding measurable fluorescence intensity in a microplate assay that is amenable to high-throughput studies1. Originally published by Naal et al.1, we have adapted this degranulation assay for the screening of drugs and toxicants and demonstrate its use here. Triclosan is a broad-spectrum antibacterial agent that is present in many consumer products and has been found to be a therapeutic aid in human allergic skin disease7-11, although the mechanism for this effect is unknown. Here we demonstrate an assay for the effect of triclosan on mast cell degranulation. We recently showed that triclosan strongly affects mast cell function2. In an effort to avoid use of an organic solvent, triclosan is dissolved directly into aqueous buffer with heat and stirring, and resultant concentration is confirmed using UV-Vis spectrophotometry (using ε280 = 4,200 L/M/cm)12. This protocol has the potential to be used with a variety of chemicals to determine their effects on mast cell degranulation, and more broadly, their allergic potential. PMID:24300285

  6. Ancient origin of mast cells

    PubMed Central

    Wong, G. William; Zhuo, Lisheng; Kimata, Koji; Lam, Bing K.; Satoh, Nori; Stevens, Richard L.

    2014-01-01

    The sentinel roles of mammalian mast cells (MCs) in varied infections raised the question of their evolutionary origin. We discovered that the test cells in the sea squirt Ciona intestinalis morphologically and histochemically resembled cutaneous human MCs. Like the latter, C. intestinalis test cells stored histamine and varied heparin•serine protease complexes in their granules. Moreover, they exocytosed these preformed mediators when exposed to compound 48/80. In support of the histamine data, a C. intestinalis-derived cDNA was isolated that resembled that which encodes histidine decarboxylase in human MCs. Like heparin-expressing mammalian MCs, activated test cells produced prostaglandin D2 and contained cDNAs that encode a protein that resembles the synthase needed for its biosynthesis in human MCs. The accumulated morphological, histochemical, biochemical, and molecular biology data suggest that the test cells in C. intestinalis are the counterparts of mammalian MCs that reside in varied connective tissues. The accumulated data point to an ancient origin of MCs that predates the emergence of the chordates >500 million years ago, well before the development of adaptive immunity. The remarkable conservation of MCs throughout evolution is consistent with their importance in innate immunity. PMID:25094046

  7. Survival after T cell-depleted haploidentical stem cell transplantation is improved using the mother as donor.

    PubMed

    Stern, Martin; Ruggeri, Loredana; Mancusi, Antonella; Bernardo, Maria Ester; de Angelis, Claudia; Bucher, Christoph; Locatelli, Franco; Aversa, Franco; Velardi, Andrea

    2008-10-01

    We hypothesized that transplacental leukocyte trafficking during pregnancy, which induces long-term, stable, reciprocal microchimerism in mother and child, might influence outcome of patients with acute leukemia given parental donor haploidentical hematopoietic stem cell transplantation (HSCT). We analyzed the outcome of 118 patients who received transplants for acute leukemia in 2 centers. Patients received highly T cell-depleted haploidentical grafts after myelo-ablative conditioning. Five-year event-free survival was better in patients who received transplants from the mother than from the father (50.6% +/- 7.6% vs 11.1% +/- 4.2%; P < .001). Better survival was the result of both reduced incidence of relapse and transplantation-related mortality. The protective effect was seen in both female and male recipients, in both lymphoid and myeloid diseases; it was more evident in patients receiving transplants in remission than in chemotherapy-resistant relapse. Incidences of rejection and acute graft-versus-host disease were not significantly influenced. Multivariate analysis confirmed donor sex in parental donor transplantation as an independent prognostic factor for survival (hazard ratio, father vs mother = 2.36; P = .003). In contrast, in a control cohort of patients who received transplants from haploidentical siblings, donor sex had no influence on outcome. Although obtained in a retrospective analysis, these data suggest that the mother of the patient should be preferred as donor for haploidentical HSCT.

  8. Prevention of immunodeficiency virus induced CD4+ T-cell depletion by prior infection with a non-pathogenic virus

    SciTech Connect

    TerWee, Julie A.; Carlson, Jennifer K.; Sprague, Wendy S.; Sondgeroth, Kerry S.; Shropshire, Sarah B.; Troyer, Jennifer L.; VandeWoude, Sue

    2008-07-20

    Immune dysregulation initiated by a profound loss of CD4+ T-cells is fundamental to HIV-induced pathogenesis. Infection of domestic cats with a non-pathogenic lentivirus prevalent in the puma (puma lentivirus, PLV or FIV{sub PCO}) prevented peripheral blood CD4+ T-cell depletion caused by subsequent virulent FIV infection. Maintenance of this critical population was not associated with a significant decrease in FIV viremia, lending support to the hypothesis that direct viral cytopathic effect is not the primary cause of immunodeficiency. Although this approach was analogous to immunization with a modified live vaccine, correlates of immunity such as a serum-neutralizing antibody or virus-specific T-cell proliferative response were not found in protected animals. Differences in cytokine transcription profile, most notably in interferon gamma, were observed between the protected and unprotected groups. These data provide support for the importance of non-adaptive enhancement of the immune response in the prevention of CD4+ T-cell loss.

  9. Signal transduction and chemotaxis in mast cells.

    PubMed

    Draber, Petr; Halova, Ivana; Polakovicova, Iva; Kawakami, Toshiaki

    2016-05-05

    Mast cells play crucial roles in both innate and adaptive arms of the immune system. Along with basophils, mast cells are essential effector cells for allergic inflammation that causes asthma, allergic rhinitis, food allergy and atopic dermatitis. Mast cells are usually increased in inflammatory sites of allergy and, upon activation, release various chemical, lipid, peptide and protein mediators of allergic reactions. Since antigen/immunoglobulin E (IgE)-mediated activation of these cells is a central event to trigger allergic reactions, innumerable studies have been conducted on how these cells are activated through cross-linking of the high-affinity IgE receptor (FcεRI). Development of mature mast cells from their progenitor cells is under the influence of several growth factors, of which the stem cell factor (SCF) seems to be the most important. Therefore, how SCF induces mast cell development and activation via its receptor, KIT, has been studied extensively, including a cross-talk between KIT and FcεRI signaling pathways. Although our understanding of the signaling mechanisms of the FcεRI and KIT pathways is far from complete, pharmaceutical applications of the knowledge about these pathways are underway. This review will focus on recent progresses in FcεRI and KIT signaling and chemotaxis.

  10. Mast cell-orchestrated immunity to pathogens

    PubMed Central

    Abraham, Soman N.; St John, Ashley L.

    2015-01-01

    Although mast cells were discovered more than a century ago, their functions beyond their role in allergic responses remained elusive until recently. However, there is a growing appreciation that an important physiological function of these cells is the recognition of pathogens and modulation of appropriate immune responses. Because of their ability to instantly release several pro-inflammatory mediators from intracellular stores and their location at the host–environment interface, mast cells have been shown to be crucial for optimal immune responses during infection. Mast cells seem to exert these effects by altering the inflammatory environment after detection of a pathogen and by mobilizing various immune cells to the site of infection and to draining lymph nodes. Interestingly, the character and timing of these responses can vary depending on the type of pathogen stimulus, location of pathogen recognition and sensitization state of the responding mast cells. Recent studies using mast cell activators as effective vaccine adjuvants show the potential of harnessing these cells to confer protective immunity against microbial pathogens. PMID:20498670

  11. Vaccine adjuvants: Tailor-made mast-cell granules

    NASA Astrophysics Data System (ADS)

    Gunzer, Matthias

    2012-03-01

    Mast cells induce protective immune responses through secretion of stimulatory granules. Microparticles modelled after mast-cell granules are now shown to replicate and enhance the functions of their natural counterparts and to direct the character of the resulting immunity.

  12. Extendable mast used in one shot soil penetrometer

    NASA Technical Reports Server (NTRS)

    Hotz, G. M.; Howard, G. A.

    1966-01-01

    Penetrometer to test soil characteristics has a piercing head with soil instrumentation equipment attached to an expandable mast actuated by compressed air. The penetrometer gives continuous measurements as the mast pushes the piercing head through the soil.

  13. Mast cells in the human alveolar wall: an electronmicroscopic study.

    PubMed Central

    Fox, B; Bull, T B; Guz, A

    1981-01-01

    Mast cells were identified by electronmicroscopy in the alveolar wall of the lung in 20 subjects (10 normal, 10 abnormal). A quantitative and qualitative study was made of the mast cells. In the normal lung there was an average concentration of 350 mast cells/mm2 of alveolar wall and in the abnormal 523/mm2. Mast cells occupied approximately 1.6-2.1% of the area of the alveolar wall. There was marked variation in the structure of the mast cell granules but no differences between those in the normal and abnormal lungs. There was evidence that constant degranulation of mast cells may be occurring in the lung. The role that alveolar mast cells may play in the vasoconstrictor response to alveolar hypoxia is discussed. It is suggested that the tachypnoea present in asthma may partly be due to release of mediators from sensitised mast cells within the alveolar wall. Images PMID:7328180

  14. Inhibitory effects of mast cell-mediated allergic reactions by cell cultured Siberian Ginseng.

    PubMed

    Jeong, H J; Koo, H N; Myung, N I; Shin, M K; Kim, J W; Kim, D K; Kim, K S; Kim, H M; Lee, Y M

    2001-02-01

    The crude drug "Siberian Ginseng (SG)" has long been used in empirical Oriental medicine for the nonspecific enhancement of resistance in humans and animals. In this study, we investigated the effect of cell cultured SG by oral administration in mast cell-mediated allergic reactions. SG dose-dependently inhibited compound 48/80-induced systemic allergy with doses of 10(-2) to 1 g/kg 1 h before oral administration. Of special note, SG inhibited systemic allergy with the dose of 1 g/kg by 25%. SG (1 g/kg) also inhibited passive cutaneous allergic reaction by 51%. SG dose-dependently inhibited histamine release from rat peritoneal mast cells. When SG (0.01 mg/ml) was added, the secretion of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 in antidinitrophenyl (DNP) IgE antibody-stimulated mast cells was inhibited 39.5% and 23.3%, respectively. In addition, SG inhibited anti-DNP IgE antibody-stimulated TNF-alpha protein expression in mast cells. Our studies provide evidence that SG may be beneficial in the treatment of various types of allergic diseases.

  15. Molecular Diagnosis of Mast Cell Disorders

    PubMed Central

    Akin, Cem

    2006-01-01

    Mastocytosis is a disease characterized by pathological mast cell accumulation and activation in tissues. Most patients with mastocytosis exhibit the D816V point mutation in the tyrosine kinase domain of the transmembrane receptor protein Kit, leading to its constitutive activation in bone marrow or lesional skin tissue. Detection of a codon 816 c-kit mutation is included as a minor diagnostic criterion in the World Health Organization’s diagnostic criteria for systemic mastocytosis. Determining mutational status of the c-kit gene also has pharmacogenomic implications in patients considered for investigational mast cell cytoreductive therapies. This article reviews diagnostic and therapeutic implications of c-kit mutations as well as other less common molecular abnormalities observed in mast cell disease. PMID:16931579

  16. Mast Cell-Mediated Mechanisms of Nociception.

    PubMed

    Aich, Anupam; Afrin, Lawrence B; Gupta, Kalpna

    2015-12-04

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner.

  17. Mast Cell-Mediated Mechanisms of Nociception

    PubMed Central

    Aich, Anupam; Afrin, Lawrence B.; Gupta, Kalpna

    2015-01-01

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner. PMID:26690128

  18. 53. VIEW FROM FLOOR OF MAST TRENCH SHOWING BASE OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. VIEW FROM FLOOR OF MAST TRENCH SHOWING BASE OF ERECT UMBILICAL MAST. AIR-CONDITIONING DUCTS VISIBLE ON RIGHT SIDE OF MAST. HYDRAULIC ACTUATOR ARMS FOR OPENING TRENCH DOORS VISIBLE ON LEFT SIDE OF PHOTO. 'DOOR STOP' PEDESTAL IN FOREGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. The Michigan Alcoholism Screening Test (MAST): A Statistical Validation Analysis

    ERIC Educational Resources Information Center

    Laux, John M.; Newman, Isadore; Brown, Russ

    2004-01-01

    This study extends the Michigan Alcoholism Screening Test (MAST; M. L. Selzer, 1971) literature base by examining 4 issues related to the validity of the MAST scores. Specifically, the authors examine the validity of the MAST scores in light of the presence of impression management, participant demographic variables, and item endorsement…

  20. Insights into mast cell functions in asthma using mouse models.

    PubMed

    Lei, Ying; Gregory, Joshua A; Nilsson, Gunnar P; Adner, Mikael

    2013-10-01

    Therapeutics targeting specific mechanisms of asthma have shown promising results in mouse models of asthma. However, these successes have not transferred well to the clinic or to the treatment of asthma sufferers. We suggest a reason for this incongruity is that mast cell-dependent responses, which may play an important role in the pathogenesis of both atopic and non-atopic asthma, are not a key component in most of the current asthma mouse models. Two reasons for this are that wild type mice have, in contrast to humans, a negligible number of mast cells localized in the smaller airways and in the parenchyma, and that only specific protocols show mast cell-dependent reactions. The development of mast cell-deficient mice and the reconstitution of mast cells within these mice have opened up the possibility to generate mouse models of asthma with a marked role of mast cells. In addition, mast cell-deficient mice engrafted with mast cells have a distribution of mast cells more similar to humans. In this article we review and highlight the mast cell-dependent and -independent responses with respect to airway hyperresponsiveness and inflammation in asthma models using mast cell-deficient and mast cell-engrafted mice.

  1. 43. TOP PART OF UMBILICAL MAST, NORTH AND WEST SIDES. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. TOP PART OF UMBILICAL MAST, NORTH AND WEST SIDES. AIR CONDITIONING DUCTING IS VISIBLE ON INTERIOR OF MAST. RAIL IS VISIBLE LEFT OF THE MAST. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  2. CD4+CD25+ Regulatory T Cell Depletion Modulates Anxiety and Depression-Like Behaviors in Mice

    PubMed Central

    Kim, Soo-Jeong; Lee, Hyojung; Lee, Gihyun; Oh, Sei-Joong; Shin, Min-Kyu; Shim, Insop; Bae, Hyunsu

    2012-01-01

    Stress has been shown to suppress immune function and increase susceptibility to inflammatory disease and psychiatric disease. CD4+CD25+ regulatory T (Treg) cells are prominent in immune regulation. This study was conducted to determine if anti-CD25 antibody (Ab) mediated depletion of Treg cells in mice susceptibility to stress-induced development of depression-like behaviors, as well as immunological and neurochemical activity. To accomplish this, an elevated plus-maze test (EPM), tail suspension test (TST), and forced swim test (FST) were used to examine depression-like behaviors upon chronic immobilization stress. Immune imbalance status was observed based on analysis of serum cytokines using a mouse cytometric bead array in conjunction with flow cytometry and changes in the levels of serotonin (5-HT) and dopamine (DA) in the brain were measured by high performance liquid chromatography (HPLC). The time spent in the open arms of the EPM decreased significantly and the immobility time in the FST increased significantly in the anti-CD25 Ab-treated group when compared with the non stressed wild-type group. In addition, interlukin-6 (IL-6), tumor necrosis factor-á (TNF-á), interlukin-2 (IL-2), interferon-gamma (IFN-γ), interlukin-4 (IL-4) and interlukin-17A (IL-17A) concentrations were significantly upregulated in the stressed anti-CD25 Ab-treated group when compared with the non stressed wild-type group. Furthermore, the non stressed anti-CD25 Ab-treated group displayed decreased 5-HT levels within the hippocampus when compared with the non stressed wild-type group. These results suggest that CD4+CD25+ Treg cell depletion modulated alterations in depressive behavior, cytokine and monoaminergic activity. Therefore, controlling CD4+CD25+ Treg cell function during stress may be a potent therapeutic strategy for the treatment of depression-like symptoms. PMID:22860054

  3. Inhibition of envelope-mediated CD4+-T-cell depletion by human immunodeficiency virus attachment inhibitors.

    PubMed

    Alexander, Louis; Zhang, Sharon; McAuliffe, Brian; Connors, David; Zhou, Nannon; Wang, Tao; Agler, Michele; Kadow, John; Lin, Pin-Fang

    2009-11-01

    Human immunodeficiency virus type 1 (HIV-1) envelope (Env) binding induces proapoptotic signals in CD4(+) T cells without a requirement of infection. Defective virus particles, which represent the majority of HIV-1, usually contain a functional Env and therefore represent a potentially significant cause of such CD4(+)-T-cell loss. We reasoned that an HIV-1 inhibitor that prohibits Env-host cell interactions could block the destructive effects of defective particles. HIV-1 attachment inhibitors (AIs), which potently inhibit Env-CD4 binding and subsequent downstream effects of Env, display low-nanomolar antiapoptotic potency and prevent CD4(+)-T-cell depletion from mixed lymphocyte cultures, also with low-nanomolar potency. Specific Env amino acid changes that confer resistance to AI antientry activity eliminate AI antiapoptotic effects. We observed that CD4(+)-T-cell destruction is specific for CXCR4-utilizing HIV-1 strains and that the fusion blocker enfuvirtide inhibits Env-mediated CD4(+)-T-cell killing but is substantially less potent than AIs. These observations, in conjunction with observed antiapoptotic activities of soluble CD4 and the CXCR4 blocker AMD3100, suggest that this AI activity functions through a mechanism common to AI antientry activity, e.g., prevention of Env conformation changes necessary for specific interactions with cellular factors that facilitate viral entry. Our study suggests that AIs, in addition to having potent antientry activity, could contribute to immune system homeostasis in individuals infected with HIV-1 that can engage CXCR4, thereby mitigating the increased risk of adverse clinical events observed in such individuals on current antiretroviral regimens.

  4. Extendable retractable telescopic mast for deployable structures

    NASA Technical Reports Server (NTRS)

    Schmid, M.; Aguirre, M.

    1986-01-01

    The Extendable and Retractable Mast (ERM) which is presently developed by Dornier in the frame of an ESA-contract, will be used to deploy and retract large foldable structures. The design is based on a telescopic carbon-fiber structure with high stiffness, strength and pointing accuracy. To verify the chosen design, a breadboard model of an ERM was built and tested under thermal vacuum (TV)-conditions. It is planned as a follow-on development to manufacture and test an Engineering Model Mast. The Engineering Model will be used to establish the basis for an ERM-family covering a wide range of requirements.

  5. GPR30 decreases cardiac chymase/angiotensin II by inhibiting local mast cell number

    SciTech Connect

    Zhao, Zhuo; Wang, Hao; Lin, Marina; Groban, Leanne

    2015-03-27

    Chronic activation of the novel estrogen receptor GPR30 by its agonist G1 mitigates the adverse effects of estrogen (E2) loss on cardiac structure and function. Using the ovariectomized (OVX) mRen2.Lewis rat, an E2-sensitive model of diastolic dysfunction, we found that E2 status is inversely correlated with local cardiac angiotensin II (Ang II) levels, likely via Ang I/chymase-mediated production. Since chymase is released from cardiac mast cells during stress (e.g., volume/pressure overload, inflammation), we hypothesized that GPR30-related cardioprotection after E2 loss might occur through its opposing actions on cardiac mast cell proliferation and chymase production. Using real-time quantitative PCR, immunohistochemistry, and immunoblot analysis, we found mast cell number, chymase expression, and cardiac Ang II levels were significantly increased in the hearts of OVX-compared to ovary-intact mRen2.Lewis rats and the GPR30 agonist G1 (50 mg/kg/day, s.c.) administered for 2 weeks limited the adverse effects of estrogen loss. In vitro studies revealed that GPR30 receptors are expressed in the RBL-2H3 mast cell line and G1 inhibits serum-induced cell proliferation in a dose-dependent manner, as determined by cell counting, BrdU incorporation assay, and Ki-67 staining. Using specific antagonists to estrogen receptors, blockage of GPR30, but not ERα or ERβ, attenuated the inhibitory effects of estrogen on BrdU incorporation in RBL-2H3 cells. Further study of the mechanism underlying the effect on cell proliferation showed that G1 inhibits cyclin-dependent kinase 1 (CDK1) mRNA and protein expression in RBL-2H3 cells in a dose-dependent manner. - Highlights: • GPR30 activation limits mast cell number in hearts from OVX mRen2.Lewis rats. • GPR30 activation decreases cardiac chymase/angiotensin II after estrogen loss. • GPR30 activation inhibits RBL-2H3 mast cell proliferation and CDK1 expression.

  6. Roles of mucosal mast cells in intestinal cell-mediated immunity

    SciTech Connect

    Ferguson, A.; Cummins, A.G.; Munro, G.H.; Gibson, S.; Miller, H.R.

    1987-11-01

    Mucosal mast cells in rats with GvHR have been studied by cell counts, tissue levels of the specific protease RMCPII, and, as an index of MMC activation, serum RMCPII. In semi-allogeneic GvHR without host irradiation, GvHR produced modest increases in these three indices. In contrast, irradiation profoundly depleted MMC even though enteropathy was more severe than in non-irradiated hosts. We suggest that enteropathy is not dependent on the presence of MMC. In rats given cyclosporin A, lesions of GvHR were mild and numbers of MMC were low.

  7. Degranulation of mast cells and inhibition of the response to secretory agents by phototoxic compounds and ultraviolet radiation

    SciTech Connect

    Gendimenico, G.J.; Kochevar, I.E.

    1984-11-01

    The symptoms of cutaneous phototoxicity from coal tar compounds and the nonsteroidal anti-inflammatory drug benoxaprofen are characterized by wheal and flare formation which is mediated by histamine released from dermal mast cells. Rat serosal mast cells were used as an in vitro model system to study the direct effect of phototoxic compounds on mast cell degranulation. The coal tar compounds studied included acridine and pyrene. Combined exposure of cells to acridine and UVA (320 to 400 nm) radiation caused mast cells to degranulate, as assayed by the release of (/sup 3/H)serotonin. Maximum (/sup 3/H)serotonin release (70 to 80%) was obtained with 50 microM acridine and 300 kJ/m2 UVA. Pyrene (25 microM), when photoexcited with UVB (280 to 360 nm) radiation, caused about 80% release of (/sup 3/H)serotonin. No degranulation occurred with 20 microM benoxaprofen and UVB doses up to 7.2 kJ/m2. Trypan blue staining correlated well with degranulation caused by acridine plus UVA; however, with pyrene plus UVB there was greater (/sup 3/H)serotonin release than dye uptake. Excitation of photosensitizers with doses of UV radiation that did not cause trypan blue staining suppressed degranulation of mast cells in response to chemical stimulation. Acridine, pyrene, and benoxaprofen in the presence of UV radiation inhibited the mast cells from responding to compound 48/80 or the calcium ionophore, chlortetracycline. Two other phototoxic compounds, chlorpromazine and deoxytetracycline, also abolished degranulation by compound 48/80. These findings indicate that phototoxic compounds: (1) cause degranulation in the presence of high doses of UV radiation; and (2) suppress degranulation of mast cells in response to secretory stimuli at doses of UV radiation that do not cause release of mediator.

  8. Inhibitory effect of açaí (Euterpe oleracea Mart.) pulp on IgE-mediated mast cell activation.

    PubMed

    Horiguchi, Tomoko; Ishiguro, Nahoko; Chihara, Kazuyasu; Ogi, Kazuhiro; Nakashima, Kenji; Sada, Kiyonao; Hori-Tamura, Naoko

    2011-05-25

    The palm fruit açaí is known to have potential health benefits due to its antioxidant scavenging capacities. Pretreatment of IgE-sensitized mouse primary cultured mast cells with açaí pulp resulted in the dramatic suppression of antigen-induced degranulation in a dose-dependent manner. Similarly, açaí suppressed IgE-mediated degranulation and transcription of the cytokine genes from a cultured mast cell line of rat basophilic leukemia (RBL)-2H3 cells. Açaí could selectively inhibit FcεRI signaling pathways. Furthermore, the FcεRI-mediated complementary signaling pathway was also suppressed by açaí. These results demonstrate that açaí is a potent inhibitor of IgE-mediated mast cell activation.

  9. Mast cells in airway diseases and interstitial lung disease.

    PubMed

    Cruse, Glenn; Bradding, Peter

    2016-05-05

    Mast cells are major effector cells of inflammation and there is strong evidence that mast cells play a significant role in asthma pathophysiology. There is also a growing body of evidence that mast cells contribute to other inflammatory and fibrotic lung diseases such as chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. This review discusses the role that mast cells play in airway diseases and highlights how mast cell microlocalisation within specific lung compartments and their cellular interactions are likely to be critical for their effector function in disease.

  10. Microscopy assays for evaluation of mast cell migration and chemotaxis.

    PubMed

    Bambousková, Monika; Hájková, Zuzana; Dráber, Pavel; Dráber, Petr

    2014-01-01

    A better understanding of the molecular mechanisms leading to mast cell migration and chemotaxis is the long-term goal in mast cell research and is essential for comprehension of mast cell function in health and disease. Various techniques have been developed in recent decades for in vitro and in vivo assessment of mast cell motility and chemotaxis. In this chapter three microscopy assays facilitating real-time quantification of mast cell chemotaxis and migration are described, focusing on individual cell tracking and data analysis.

  11. Mast Cell: A Multi-Functional Master Cell

    PubMed Central

    Krystel-Whittemore, Melissa; Dileepan, Kottarappat N.; Wood, John G.

    2016-01-01

    Mast cells are immune cells of the myeloid lineage and are present in connective tissues throughout the body. The activation and degranulation of mast cells significantly modulates many aspects of physiological and pathological conditions in various settings. With respect to normal physiological functions, mast cells are known to regulate vasodilation, vascular homeostasis, innate and adaptive immune responses, angiogenesis, and venom detoxification. On the other hand, mast cells have also been implicated in the pathophysiology of many diseases, including allergy, asthma, anaphylaxis, gastrointestinal disorders, many types of malignancies, and cardiovascular diseases. This review summarizes the current understanding of the role of mast cells in many pathophysiological conditions. PMID:26779180

  12. Addition of an Indoleamine-2,3,-dioxygenase Inhibitor to B cell Depletion Therapy Blocks Autoreactive B Cell Activation and Recurrence of Arthritis

    PubMed Central

    Pigott, Elizabeth; Mandik-Nayak, Laura

    2012-01-01

    Objective Define the role indoleamine-2,3-dioxygenase (IDO) plays in driving pathogenic B cells responses leading to arthritis and determine if inhibitors of the IDO pathway can be used in conjunction with B cell depletion therapy to prevent the re-emergence of autoantibodies and arthritis following reconstitution of the B cell repertoire. Methods Immunoglobulin transgenic mice were treated with the IDO inhibitor 1-methyl-tryptophan (1MT) and followed for the extent of autoreactive B cell activation. Arthritic mice (K/BxN) were treated with B cell depletion therapy alone or in combination with 1MT. Mice were followed for the presence of autoantibody secreting cells, inflammatory cytokines, and joint inflammation. Results 1MT did not affect the initial activation or survival of autoreactive B cells, but did inhibit their ability to differentiate into autoantibody secreting cells. Treatment with anti-CD20 depleted the B cell repertoire and attenuated arthritis symptoms; however, arthritis symptoms rapidly returned as B cells repopulated the repertoire. Administration of 1MT prior to B cell repopulation prevented the production of autoantibodies, inflammatory cytokines, and flare in arthritis symptoms. Conclusion IDO activity is essential for the differentiation of autoreactive B cells into antibody secreting cells, but is not necessary for their initial stages of activation. Addition of 1MT to B cell depletion therapy prevents the differentiation of autoantibody secreting cells and recurrence of autoimmune arthritis following reconstitution of the B cell repertoire. These data suggest that IDO inhibitors could be used in conjunction with B cell depletion as an effective co-therapeutic strategy in the treatment of rheumatoid arthritis. PMID:22294267

  13. Silver Nanoparticle-Directed Mast Cell Degranulation Is Mediated through Calcium and PI3K Signaling Independent of the High Affinity IgE Receptor

    PubMed Central

    Alsaleh, Nasser B.; Persaud, Indushekhar; Brown, Jared M.

    2016-01-01

    Engineered nanomaterial (ENM)-mediated toxicity often involves triggering immune responses. Mast cells can regulate both innate and adaptive immune responses and are key effectors in allergic diseases and inflammation. Silver nanoparticles (AgNPs) are one of the most prevalent nanomaterials used in consumer products due to their antimicrobial properties. We have previously shown that AgNPs induce mast cell degranulation that was dependent on nanoparticle physicochemical properties. Furthermore, we identified a role for scavenger receptor B1 (SR-B1) in AgNP-mediated mast cell degranulation. However, it is completely unknown how SR-B1 mediates mast cell degranulation and the intracellular signaling pathways involved. In the current study, we hypothesized that SR-B1 interaction with AgNPs directs mast cell degranulation through activation of signal transduction pathways that culminate in an increase in intracellular calcium signal leading to mast cell degranulation. For these studies, we utilized bone marrow-derived mast cells (BMMC) isolated from C57Bl/6 mice and RBL-2H3 cells (rat basophilic leukemia cell line). Our data support our hypothesis and show that AgNP-directed mast cell degranulation involves activation of PI3K, PLCγ and an increase in intracellular calcium levels. Moreover, we found that influx of extracellular calcium is required for the cells to degranulate in response to AgNP exposure and is mediated at least partially via the CRAC channels. Taken together, our results provide new insights into AgNP-induced mast cell activation that are key for designing novel ENMs that are devoid of immune system activation. PMID:27907088

  14. Efficacy of a rituximab regimen based on B cell depletion in thrombotic thrombocytopenic purpura with suboptimal response to standard treatment: Results of a phase II, multicenter noncomparative study.

    PubMed

    Benhamou, Ygal; Paintaud, Gilles; Azoulay, Elie; Poullin, Pascale; Galicier, Lionel; Desvignes, Céline; Baudel, Jean-Luc; Peltier, Julie; Mira, Jean-Paul; Pène, Frédéric; Presne, Claire; Saheb, Samir; Deligny, Christophe; Rousseau, Alexandra; Féger, Frédéric; Veyradier, Agnès; Coppo, Paul

    2016-12-01

    The standard four-rituximab infusions treatment in acquired thrombotic thrombocytopenic purpura (TTP) remains empirical. Peripheral B cell depletion is correlated with the decrease in serum concentrations of anti-ADAMTS13 and associated with clinical response. To assess the efficacy of a rituximab regimen based on B cell depletion, 24 TTP patients were enrolled in this prospective multicentre single arm phase II study and then compared to patients from a previous study. Patients with a suboptimal response to a plasma exchange-based regimen received two infusions of rituximab 375 mg m(-2) within 4 days, and a third dose at day +15 of the first infusion if peripheral B cells were still detectable. Primary endpoint was the assessment of the time required to platelet count recovery from the first plasma exchange. Three patients died after the first rituximab administration. In the remaining patients, the B cell-driven treatment hastened remission and ADAMTS13 activity recovery as a result of rapid anti-ADAMTS13 depletion in a similar manner to the standard four-rituximab infusions schedule. The 1-year relapse-free survival was also comparable between both groups. A rituximab regimen based on B cell depletion is feasible and provides comparable results than with the four-rituximab infusions schedule. This regimen could represent a new standard in TTP. This trial was registered at www.clinicaltrials.gov (NCT00907751). Am. J. Hematol. 91:1246-1251, 2016. © 2016 Wiley Periodicals, Inc.

  15. Mosla dianthera inhibits mast cell-mediated allergic reactions through the inhibition of histamine release and inflammatory cytokine production

    SciTech Connect

    Lee, Dong-Hee; Kim, Sang-Hyun . E-mail: shkim72@knu.ac.kr; Eun, Jae-Soon; Shin, Tae-Yong . E-mail: tyshin@woosuk.ac.kr

    2006-11-01

    In this study, we investigated the effect of the aqueous extract of Mosla dianthera (Maxim.) (AEMD) on the mast cell-mediated allergy model and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases such as asthma, sinusitis and rheumatoid arthritis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. AEMD inhibited compound 48/80-induced systemic reactions in mice. AEMD decreased immunoglobulin E-mediated local allergic reactions, passive cutaneous anaphylaxis. AEMD attenuated intracellular calcium level and release of histamine from rat peritoneal mast cells activated by compound 48/80. Furthermore, AEMD attenuated the phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated TNF-{alpha}, IL-8 and IL-6 secretion in human mast cells. The inhibitory effect of AEMD on the pro-inflammatory cytokines was nuclear factor-{kappa}B (NF-{kappa}B) dependent. AEMD decreased PMA and A23187-induced degradation of I{kappa}B{alpha} and nuclear translocation of NF-{kappa}B. Our findings provide evidence that AEMD inhibits mast cell-derived immediate-type allergic reactions and involvement of pro-inflammatory cytokines and NF-{kappa}B in these effects.

  16. Mechanism of the modulation of murine peritoneal cell function and mast cell degranulation by low doses of malathion.

    PubMed

    Rodgers, K; Ellefson, D

    1992-01-01

    Malathion is a widely used organophosphate pesticide that modulates immune function at noncholinergic doses. Previous studies showed that this alteration in immune function was the result of enhanced macrophage function. In the present study, the effects of low doses of purified malathion (as low as 0.25 mg/kg malathion) administered orally to mice enhanced the respiratory burst of peritoneal cells. Microscopic examination of the peritoneal cells showed that mast cells were degranulated within 4 hr after malathion administration. The amount of beta-hexosaminidase, an enzyme released upon immunologic degranulation of mast cells, in the peritoneal lavage fluid of malathion-treated mice was also significantly elevated with 4 hours after malathion administration. Treatment of RBL-1, a rat basophilic cell line, cells with malathion, parathion or paroxon in vitro also led to the release of beta-hexosaminidase with paraoxon being the most potent. Further examination of the peritoneal cells of malathion-treated mice showed that the percentage of phagocytic peritoneal cells ingesting mast cell granules and the number of granules ingested per cell were elevated. These data suggest that malathion may enhance the respiratory burst of peritoneal cells through degranulation of peritoneal mast cells and the subsequent exposure to peritoneal cells to mast cell mediators.

  17. P2 receptor-mediated signaling in mast cell biology.

    PubMed

    Bulanova, Elena; Bulfone-Paus, Silvia

    2010-03-01

    Mast cells are widely recognized as effector cells of allergic inflammatory reactions. They contribute to the pathogenesis of different chronic inflammatory diseases, wound healing, fibrosis, thrombosis/fibrinolysis, and anti-tumor immune responses. In this paper, we summarized the role of P2X and P2Y receptors in mast cell activation and effector functions. Mast cells are an abundant source of ATP which is stored in their granules and secreted upon activation. We discuss the contribution of mast cells to the extracellular ATP release and to the maintenance of extracellular nucleotides pool. Recent publications highlight the importance of purinergic signaling for the pathogenesis of chronic airway inflammation. Therefore, the role of ATP and P2 receptors in allergic inflammation with focus on mast cells was analyzed. Finally, ATP functions as mast cell autocrine/paracrine factor and as messenger in intercellular communication between mast cells, nerves, and glia in the central nervous system.

  18. Malicious Activity Simulation Tool (MAST) and Trust

    DTIC Science & Technology

    2015-06-01

    Protocol IS Information System ISSM Information System Security Manager IT Information Technology MAC Media Access Control MAC Mission Assurance...Category MAST Malicious Activity Simulation Tool NIST National Institute of Standards and Technology OWASP Open Web Application Security...Department of Defense (DOD). Adversary tactics are always evolving, as are the information technology environments that they attack. Operators remain

  19. Development, significance, and heterogeneity of mast cells with particular regard to the mast cell-specific proteases chymase and tryptase.

    PubMed

    Welle, M

    1997-03-01

    Mast cells are one of the major effector cells in the pathogenesis of the immediate-type hypersensitivity reaction in a number of non-allergic immune disorders as well as in normal physiological processes. In addition, it has been shown recently that mast cells also play a significant role in a life-saving host response to bacterial reactions. But as much as the immunopathological role of mast cells has been acknowledged, these cells have also aroused much controversy and confusion. By now it is clear that one explanation for the sometimes even contradictory opinions on mast cell function arise from mast cell heterogeneity. This heterogeneity can express itself as differences in histochemical, biochemical, and functional characteristics. In vitro systems provided a powerful tool for the investigation of the basic mechanisms for mast cell development and differentiation and helped to demonstrate that mast cell heterogeneity can be traced back to certain cytokine patterns that are present in different microenvironments. In this context it has also been shown that the growth factors required for human mast cell differentiation are somewhat different than those for rodents. In rodents, the atypical, T cell-dependent mucosal type mast cell can be distinguished from the T cell-independent connective tissue-type mast cell. In humans, the strict classification into mucosal and connective tissue-type mast cells is not possible and the content of mast cell-specific proteases chymase and tryptase is the main criterion for mast cell subtypes in humans. The large quantities of tryptase and chymase that are synthesized by mast cells suggest and emphasize the significance of these proteinases in mast cell function and stimulated investigations about the biological properties of these mast cell-specific proteases. Comparing their biological activities it becomes clear that they share some activities. On the other hand, tryptase seems to participate in proinflammatory mast cell

  20. Studies on the pH gradient and histamine uptake of isolated mast cell granules

    SciTech Connect

    De Young, M.B.; Nemeth, E.F.; Scarpa, A.

    1986-05-01

    A purified preparation of mast cell granules with intact perigranular membranes was obtained using a method involving probe sonication of rat serosal mast cells followed by differential centrifugation and Percoll gradient separation of the granules. Purification was assessed with histamine and mast cell granule protease assays. Granule integrity was demonstrated by light and electron microscopy and quantitated with a ruthenium red binding assay. The low yield of granules (20 ..mu..g protein/4 rats) necessitated the development of two microanalytical techniques to demonstrate the existence of a pH gradient across the membrane: 9-aminoacridine fluorescence studies in a cuvet with 50 ..mu..l capacity and /sup 14/C-methylamine distribution studies on microgram quantities of granule protein. Quantitation of results from isotope studies were confounded by the presence of oil used for separating granules from the aqueous phase. Nonetheless, an extrapolation procedure calibrated by external pH yielded an internal pH value of 5.46 +/- .03 (n = 4), consistent with values observed in granules obtained from other secretory cells. Collapse of the pH gradient by NH/sub 4//sup +/ or nigericin/KCl was demonstrated using either technique. Addition of histamine depressed intragranular pH, suggesting that histamine transport may utilize the ..delta..pH as a driving force.

  1. Monitoring of immune cell response to B cell depletion therapy and nerve root injury using SPIO enhanced MRI

    NASA Astrophysics Data System (ADS)

    Thorek, Daniel L.

    2009-12-01

    Magnetic resonance (MR) is a robust platform for non-invasive, high-resolution anatomical imaging. However, MR imaging lacks the requisite sensitivity and contrast for imaging at the cellular level. This represents a clinical impediment to greater diagnostic accuracy. Recent advances have allowed for the in vivo visualization of populations and even of individual cells using superparamagnetic iron oxide (SPIO) MR contrast agents. These nanoparticles, commonly manifested as a core of a single iron oxide crystal or cluster of crystals coated in a biocompatible shell, function to shorten proton relaxation times. In MR imaging these constructs locally dephase protons, resulting in a decrease in signal (hypointensity) localized to the region of accumulation of SPIO. In the context of immune cell imaging, SPIO can provide insight into the cellular migration patterns, trafficking, temporal dynamics and progression of diseases and their related pathological states. Furthermore, by visualizing the presence and activity of immune cells, SPIO-enabled cellular imaging can help evaluate the efficacy of therapy in immune disorders. This thesis examines the production, modification and application of SPIO in a range of in vitro and in vivo immune-response-relevant cellular systems. The role of different nanoparticle characteristics including diameter, surface charge and concentration are investigated in the labeling of T cells in culture. Following optimization of SPIO loading conditions for lymphocytes, the effect these particles have on the activation of primary B cells are elucidated. B cells are tracked using a variety of modalities, with and without the application of B cell depleting therapy. This is to evaluate the efficacy of SPIO as in vivo marker for B cell distribution. Unmodified SPIO were applied to monitor macrophage infiltration in a transient nerve root compression model, with implications for neck pain diagnosis and treatment. Nanoparticle accumulation and MR

  2. Activation of basophil and mast cell histamine release by eosinophil granule major basic protein

    PubMed Central

    1983-01-01

    Major basic protein (MBP) is a primary constituent of eosinophil granules. In this report, we demonstrate that MBP from human eosinophil granules initiates a nonlytic histamine release from human leukocytes. A direct effect of MBP on basophils was confirmed using purified human basophils. The kinetics of release were similar to those reported for poly-L-arginine, although MBP was less potent than poly-L-arginine of similar molecular weight. Reduction and alkylation of MBP diminished both the potency and efficacy of the molecule. Native MBP also stimulated histamine secretion from purified rat peritoneal mast cells in a manner characteristic of other polycations. These results emphasize the bidirectional nature of the basophil/mast cell-eosinophil regulatory axis. PMID:6854212

  3. Mast Cells Produce a Unique Chondroitin Sulfate Epitope

    PubMed Central

    Farrugia, Brooke L.; Whitelock, John M.; O’Grady, Robert; Caterson, Bruce; Lord, Megan S.

    2015-01-01

    The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells that was detected with the antibody clone 2B6 in the absence of chondroitinase ABC digestion. Mast cells in rodent tissue sections were characterized using toluidine blue, Leder stain and the presence of mast cell tryptase. The novel CS epitope was identified in rodent tissue sections and localized to cells that were morphologically similar to cells chemically identified as mast cells. The rodent mast cell-like line RBL-2H3 was also shown to express the novel CS epitope. This epitope co-localized with multiple CS proteoglycans in both rodent tissue and RBL-2H3 cultured cells. These findings suggest that the novel CS epitope that decorates mast cell proteoglycans may play a role in the way these chains are structured in mast cells. PMID:26586669

  4. Mast cells as targets for immunotherapy of solid tumors.

    PubMed

    Oldford, Sharon A; Marshall, Jean S

    2015-01-01

    Mast cells have historically been studied mainly in the context of allergic disease. In recent years, we have come to understand the critical importance of mast cells in tissue remodeling events and their role as sentinel cells in the induction and development of effective immune responses to infection. Studies of the role of mast cells in tumor immunity are more limited. The pro-tumorigenic role of mast cells has been widely reported. However, mast cell infiltration predicts improved prognosis in some cancers, suggesting that their prognostic value may be dependent on other variables. Such factors may include the nature of local mast cell subsets and the various activation stimuli present within the tumor microenvironment. Experimental models have highlighted the importance of mast cells in orchestrating the anti-tumor events that follow immunotherapies that target innate immunity. Mast cells are long-lived tissue resident cells that are abundant around many solid tumors and are radiation resistant making them unique candidates for combined treatment modalities. This review will examine some of the key roles of mast cells in tumor immunity, with a focus on potential immunotherapeutic interventions that harness the sentinel role of mast cells.

  5. Mast Cells Produce a Unique Chondroitin Sulfate Epitope.

    PubMed

    Farrugia, Brooke L; Whitelock, John M; O'Grady, Robert; Caterson, Bruce; Lord, Megan S

    2016-02-01

    The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells that was detected with the antibody clone 2B6 in the absence of chondroitinase ABC digestion. Mast cells in rodent tissue sections were characterized using toluidine blue, Leder stain and the presence of mast cell tryptase. The novel CS epitope was identified in rodent tissue sections and localized to cells that were morphologically similar to cells chemically identified as mast cells. The rodent mast cell-like line RBL-2H3 was also shown to express the novel CS epitope. This epitope co-localized with multiple CS proteoglycans in both rodent tissue and RBL-2H3 cultured cells. These findings suggest that the novel CS epitope that decorates mast cell proteoglycans may play a role in the way these chains are structured in mast cells.

  6. Brain mast cell relationship to neurovasculature during development.

    PubMed

    Khalil, Mona; Ronda, Jocelyn; Weintraub, Michael; Jain, Kim; Silver, Rae; Silverman, Ann-Judith

    2007-09-26

    Mast cells, derived from the hematopoietic stem cell, are present in the brain from birth. During development, mast cells occur in two locations, namely the pia and the brain parenchyma. The current hypothesis regarding their origin states that brain mast cells (or their precursors) enter the pia and access the thalamus by traveling along the abluminal wall of penetrating blood vessels. The population in the pia reaches a maximum at postnatal (PN) day 11, and declines rapidly thereafter. Chromatin fragmentation suggests that this cell loss is due to apoptosis. In contrast, the thalamic population expands from PN8 to reach adult levels at PN30. Stereological analysis demonstrates that mast cells home to blood vessels. More than 96% of mast cells are inside the blood-brain barrier, with ~90% contacting the blood vessel wall or its extracellular matrix. Mast cells express alpha4 integrins -- a potential mechanism for adhesion to the vascular wall. Despite the steady increase in the volume of microvasculature, at all ages studied, mast cells are preferentially located on large diameter vessels (>16 microm; possibly arteries), and contact only those maturing blood vessels that are ensheathed by astroglial processes. Mast cells not only home to large vessels but also maintain a preferential position at branch points, sites of vessel growth. This observation presents the possibility that mast cells participate in and/or regulate vasculature growth or differentiation. The biochemical and molecular signals that induce mast cell homing in the CNS is an area of active investigation.

  7. Isolation, culture, and characterization of intestinal mast cells.

    PubMed

    Sellge, Gernot; Bischoff, Stephan C

    2006-01-01

    Mast cells are bone-marrow-derived tissue cells typically located at barrier sites of the body, such as skin, mucosal barriers, or blood barriers, that is, around blood vessels. This location suggests that mast cells might have a function as immunological "gate-keepers" or "watch dogs" and, indeed, some recent functional data support this idea. Mast cells derive from myeloid progenitors, but in contrast to other myeloid cells, they leave the bone marrow in an immature state; therefore, mast cells are not found in the blood under normal conditions. For full maturation, the tissue environment is necessary. Thus, mature mast cells can be only isolated from tissue such as skin or mucosal sites, which makes mast cell isolation rather complicated. Alternatively, mast cell progenitors can be isolated from the bone marrow, peripheral blood, or cord blood, which is easier but requires subsequent in vitro maturation of mast cells as far as possible using cytokines. This chapter describes a rather new technique of mast cell isolation from human intestinal mucosal tissue yielding approx 1-5 million pure and viable human mast cells suitable to perform functional and cell culture experiments.

  8. Of mast and mean: differential-temperature cue makes mast seeding insensitive to climate change.

    PubMed

    Kelly, Dave; Geldenhuis, Andre; James, Alex; Penelope Holland, E; Plank, Michael J; Brockie, Robert E; Cowan, Philip E; Harper, Grant A; Lee, William G; Maitland, Matt J; Mark, Alan F; Mills, James A; Wilson, Peter R; Byrom, Andrea E

    2013-01-01

    Mast-seeding plants often produce high seed crops the year after a warm spring or summer, but the warm-temperature model has inconsistent predictive ability. Here, we show for 26 long-term data sets from five plant families that the temperature difference between the two previous summers (ΔT) better predicts seed crops. This discovery explains how masting species tailor their flowering patterns to sites across altitudinal temperature gradients; predicts that masting will be unaffected by increasing mean temperatures under climate change; improves prediction of impacts on seed consumers; demonstrates that strongly masting species are hypersensitive to climate; explains the rarity of consecutive high-seed years without invoking resource constraints; and generates hypotheses about physiological mechanisms in plants and insect seed predators. For plants, ΔT has many attributes of an ideal cue. This temperature-difference model clarifies our understanding of mast seeding under environmental change, and could also be applied to other cues, such as rainfall.

  9. Formation of a Mast Cell Synapse: FcεRI Membrane Dynamics upon Binding Mobile or Immobilized Ligands on Surfaces1

    PubMed Central

    Carroll-Portillo, Amanda; Spendier, Kathrin; Pfeiffer, Janet; Griffiths, Gary; Li, Haitao; Lidke, Keith A.; Oliver, Janet M.; Lidke, Diane S.; Thomas, James L.; Wilson, Bridget S.; Timlin, Jerilyn A.

    2011-01-01

    High affinity IgE receptors (FcεRI) on mast cells form a “synapse” when presented with mobile, bilayer incorporated antigen. Here, we show that receptor reorganization within the contacting mast cell membrane is markedly different upon binding of mobile and immobilized ligands. Rat basophilic leukemia mast cells (RBL-2H3) primed with fluorescent anti-DNP IgE were engaged by surfaces presenting either bilayer-incorporated, monovalent DNP-lipid (mobile ligand) or chemically crosslinked, multivalent DNP (immobilized ligand). Total internal reflection fluorescence imaging and electron microscopy methods were used to visualize receptor reorganization at the contact site. The spatial relationships of FcεRI to other cellular components at the synapse, such as actin, cholesterol and LAT, were also analyzed. Stimulation of mast cells with immobilized polyvalent ligand resulted in typical levels of degranulation. Remarkably, degranulation also followed interaction of mast cells with bilayers presenting mobile, monovalent ligand. Receptors engaged with mobile ligand coalesce into large, cholesterol-rich clusters that occupy the central portion of the contacting membrane. These data indicate that FcεRI crosslinking is not an obligatory step in triggering mast cell signaling and suggest that dense populations of mobile receptors are capable of initiating low level degranulation upon ligand recognition. PMID:20042583

  10. Mast cells and histamine are triggering the NF-κB-mediated reactions of adult and aged perilymphatic mesenteric tissues to acute inflammation

    PubMed Central

    Nizamutdinova, Irina Tsoy; Dusio, Giuseppina F.; Gasheva, Olga Yu.; Skoog, Hunter; Tobin, Richard; Peddaboina, Chander; Meininger, Cynthia J.; Zawieja, David C.; Newell-Rogers, M. Karen; Gashev, Anatoliy A.

    2016-01-01

    This study aimed to establish mechanistic links between the aging-associated changes in the functional status of mast cells and the altered responses of mesenteric tissue and mesenteric lymphatic vessels (MLVs) to acute inflammation. We used an in vivo model of acute peritoneal inflammation induced by lipopolysaccharide treatment of adult (9-month) and aged (24-month) F-344 rats. We analyzed contractility of isolated MLVs, mast cell activation, activation of nuclear factor-κB (NF-κB) without and with stabilization of mast cells by cromolyn or blockade of all types of histamine receptors and production of 27 major pro-inflammatory cytokines in adult and aged perilymphatic mesenteric tissues and blood. We found that the reactivity of aged contracting lymphatic vessels to LPS-induced acute inflammation was abolished and that activated mast cells trigger NF-κB signaling in the mesentery through release of histamine. The aging-associated basal activation of mesenteric mast cells limits acute inflammatory NF-κB activation in aged mesentery. We conclude that proper functioning of the mast cell/histamine/NF-κB axis is necessary for reactions of the lymphatic vessels to acute inflammatory stimuli as well as for interaction and trafficking of immune cells near and within the collecting lymphatics. PMID:27875806

  11. MAST Propellant and Delivery System Design Methods

    NASA Technical Reports Server (NTRS)

    Nadeem, Uzair; Mc Cleskey, Carey M.

    2015-01-01

    A Mars Aerospace Taxi (MAST) concept and propellant storage and delivery case study is undergoing investigation by NASA's Element Design and Architectural Impact (EDAI) design and analysis forum. The MAST lander concept envisions landing with its ascent propellant storage tanks empty and supplying these reusable Mars landers with propellant that is generated and transferred while on the Mars surface. The report provides an overview of the data derived from modeling between different methods of propellant line routing (or "lining") and differentiate the resulting design and operations complexity of fluid and gaseous paths based on a given set of fluid sources and destinations. The EDAI team desires a rough-order-magnitude algorithm for estimating the lining characteristics (i.e., the plumbing mass and complexity) associated different numbers of vehicle propellant sources and destinations. This paper explored the feasibility of preparing a mathematically sound algorithm for this purpose, and offers a method for the EDAI team to implement.

  12. Molecular basis of mast cell disease.

    PubMed

    Soucie, Erinn; Brenet, Fabienne; Dubreuil, Patrice

    2015-01-01

    Mastocytosis is an incurable and sometimes fatal haematological disorder grossly described as the accumulation of abnormal mast cells in the bone marrow and other organs causing tissue and organ damage. The clinical manifestations of this disease are extremely variable; disease phenotypes range from indolent to aggressive, and often present with associated non-mast cell haematological disorders (AHNMD), mainly myeloproliferative neoplasm and myelodysplastic syndromes. Recent efforts to genetically dissect the mechanisms that define aggressive and non-aggressive mastocytosis have generated a list of recurrent somatic mutations in mastocytosis patients that are associated with and may predict the evolution towards aggressive disease phenotypes. Here we review these mutations and discuss the molecular mechanisms associated with these mutations in an effort to better understand the biology of this disease and to predict its onset and evolution, with the ultimate goal of devising new and improved treatment strategies.

  13. Hymenoptera Allergy and Mast Cell Activation Syndromes.

    PubMed

    Bonadonna, Patrizia; Bonifacio, Massimiliano; Lombardo, Carla; Zanotti, Roberta

    2016-01-01

    Mast cell activation syndrome (MCAS) can be diagnosed in patients with recurrent, severe symptoms from mast cell (MC)-derived mediators, which are transiently increased in serum and are attenuated by mediator-targeting drugs. When KIT-mutated, clonal MC are detected in these patients, a diagnosis of primary MCAS can be made. Severe systemic reactions to hymenoptera venom (HV) represent the most common form of anaphylaxis in patients with mastocytosis. Patients with primary MCAS and HV anaphylaxis are predominantly males and do not have skin lesions in the majority of cases, and anaphylaxis is characterized by hypotension and syncope in the absence of urticaria and angioedema. A normal value of tryptase (≤11.4 ng/ml) in these patients does not exclude a diagnosis of mastocytosis. Patients with primary MCAS and HV anaphylaxis have to undergo lifelong venom immunotherapy, in order to prevent further potentially fatal severe reactions.

  14. EBW simulation for MAST and NSTX experiments

    SciTech Connect

    Preinhaelter, J.; Urban, J.; Pavlo, P.; Shevchenko, V.; Valovic, M.; Vahala, G.

    2005-09-26

    The interpretation of EBW emission from spherical tokamaks is nontrivial. We report on a 3D simulation model of this process that incorporates Gaussian beams for the antenna, a full wave solution of EBW-X and EBW-X-O conversions using adaptive finite elements, and EBW ray tracing to determine the radiative temperature. This model is then used to interpret the experimental results from MAST and NSTX. EBW for ELM free H-modes in MAST suggests that the magnetic equilibrium determined by the EFIT code does not adequately represent the B-field within the transport barrier. Using the EBW signal for the reconstruction of the radial profile of the magnetic field, we determine a new equilibrium and see that the EBW simulation now yields better agreement with experimental results. EBW simulations yield excellent results for the time development of the plasma temperature as measured by the EBW radiometer on NSTX.

  15. Controversial role of mast cells in skin cancers.

    PubMed

    Varricchi, Gilda; Galdiero, Maria R; Marone, Giancarlo; Granata, Francescopaolo; Borriello, Francesco; Marone, Gianni

    2017-01-01

    Cancer development is a multistep process characterized by genetic and epigenetic alterations during tumor initiation and progression. The stromal microenvironment can promote tumor development. Mast cells, widely distributed throughout all tissues, are a stromal component of many solid and haematologic tumors. Mast cells can be found in human and mouse models of skin cancers such as melanoma, basal and squamous cell carcinomas, primary cutaneous lymphomas, haemangiomas and Merkel cell carcinoma. However, human and animal studies addressing potential functions of mast cells and their mediators in skin cancers have provided conflicting results. In several studies, mast cells play a pro-tumorigenic role, whereas in others, they play an anti-tumorigenic role. Other studies have failed to demonstrate a clear role for tumor-associated mast cells. Many unanswered questions need to be addressed before we understand whether tumor-associated mast cells are adversaries, allies or simply innocent bystanders in different types and subtypes of skin cancers.

  16. Characterization of mast cell secretory granules and their cell biology.

    PubMed

    Azouz, Nurit Pereg; Hammel, Ilan; Sagi-Eisenberg, Ronit

    2014-10-01

    Exocytosis and secretion of secretory granule (SG) contained inflammatory mediators is the primary mechanism by which mast cells exert their protective immune responses in host defense, as well as their pathological functions in allergic reactions and anaphylaxis. Despite their central role in mast cell function, the molecular mechanisms underlying the biogenesis and secretion of mast cell SGs remain largely unresolved. Early studies have established the lysosomal nature of the mast cell SGs and implicated SG homotypic fusion as an important step occurring during both their biogenesis and compound secretion. However, the molecular mechanisms that account for key features of this process largely remain to be defined. A novel high-resolution imaging based methodology allowed us to screen Rab GTPases for their phenotypic and functional impact and identify Rab networks that regulate mast cell secretion. This screen has identified Rab5 as a novel regulator of homotypic fusion of the mast cell SGs that thereby regulates their size and cargo composition.

  17. Twenty-first century mast cell stabilizers

    PubMed Central

    Finn, D F; Walsh, J J

    2013-01-01

    Mast cell stabilizing drugs inhibit the release of allergic mediators from mast cells and are used clinically to prevent allergic reactions to common allergens. Despite the relative success of the most commonly prescribed mast cell stabilizer, disodium cromoglycate, in use for the preventative treatment of bronchial asthma, allergic conjunctivitis and vernal keratoconjunctivitis, there still remains an urgent need to design new substances that are less expensive and require less frequent dosing schedules. In this regard, recent developments towards the discovery of the next generation of mast cell stabilizing drugs has included studies on substances isolated from natural sources, biological, newly synthesized compounds and drugs licensed for other indications. The diversity of natural products evaluated range from simple phenols, alkaloids, terpenes to simple amino acids. While in some cases their precise mode of action remains unknown it has nevertheless sparked interest in the development of synthetic derivatives with improved pharmacological properties. Within the purely synthetic class of inhibitors, particular attention has been devoted to the inhibition of important signalling molecules including spleen TK and JAK3. The statin class of cholesterol-lowering drugs as well as nilotinib, a TK inhibitor, are just some examples of clinically used drugs that have been evaluated for their anti-allergic properties. Here, we examine each approach under investigation, summarize the test data generated and offer suggestions for further preclinical evaluation before their therapeutic potential can be realized. Linked Articles This article is part of a themed issue on Histamine Pharmacology Update. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2013.170.issue-1 PMID:23441583

  18. iMAST Quarterly, 2007 Number 1

    DTIC Science & Technology

    2007-01-01

    pitting surface damage due to corrosion and fatigue. Removal of the surface damage on these gears, however, using the ISF process, has shown that the...the flight control bridge where both corrosion and Figure . Micrograph of Copper powder deposited on Al- 6061 . The mixing of the materials at...the interface is clearly visible.[7] Figure 3. SH-60 Helicopter Transmission Gearbox Figure 4. Corrosion on Gearbox Al- 6061 Cu iMAST Quarterly 007 No

  19. B-cell depletion inhibits arthritis in a collagen-induced arthritis (CIA) model, but does not adversely affect humoral responses in a respiratory syncytial virus (RSV) vaccination model.

    PubMed

    Dunussi-Joannopoulos, Kyri; Hancock, Gerald E; Kunz, Arthur; Hegen, Martin; Zhou, Xiaochuan X; Sheppard, Barbara J; Lamothe, Jennifer; Li, Evelyn; Ma, Hak-Ling; Hamann, Philip R; Damle, Nitin K; Collins, Mary

    2005-10-01

    We report the development of a mouse B cell-depleting immunoconjugate (anti-CD22 monoclonal antibody [mAb] conjugated to calicheamicin) and its in vivo use to characterize the kinetics of CD22+ B-cell depletion and reconstitution in murine primary and secondary lymphoid tissues. The effect of B-cell depletion was further studied in a murine collagen-induced arthritis (CIA) model and a respiratory syncytial virus (RSV) vaccination model. Our results show that (1) the immunoconjugate has B-cell-specific in vitro and in vivo cytotoxicity; (2) B-cell reconstitution starts in the bone marrow and spleen around day 30 after depletion and is completed in all tissues tested by day 50; (3) B-cell depletion inhibits the development of clinical and histologic arthritis in the CIA model; (4) depletion of type II collagen antibody levels is not necessary for clinical and histologic prevention of CIA; and (5) B-cell depletion does not adversely affect memory antibody responses after challenge nor clearance of infectious virus from lungs in the RSV vaccination model. These results demonstrate for the first time that only B-cell reduction but not type II collagen antibody levels correlate with the prevention of arthritis and represent key insights into the role of CD22-targeted B-cell depletion in mouse autoimmunity and vaccination models.

  20. Macroscopic stability of high β MAST plasmas

    NASA Astrophysics Data System (ADS)

    Chapman, I. T.; Cooper, W. A.; Graves, J. P.; Gryaznevich, M. P.; Hastie, R. J.; Hender, T. C.; Howell, D. F.; Hua, M.-D.; Huysmans, G. T. A.; Keeling, D. L.; Liu, Y. Q.; Meyer, H. F.; Michael, C. A.; Pinches, S. D.; Saarelma, S.; Sabbagh, S. A.; MAST Team

    2011-07-01

    The high-beta capability of the spherical tokamak, coupled with a suite of world-leading diagnostics on MAST, has facilitated significant improvements in the understanding of performance-limiting core instabilities in high performance plasmas. For instance, the newly installed motional Stark effect diagnostic, with radial resolution <25 mm, has enabled detailed study of saturated long-lived modes in hybrid scenarios. Similarly, the upgraded Thomson scattering system, with radial resolution <10 mm and the possibility of temporal resolution of 1 µs, has allowed detailed analysis of the density and temperature profiles during transient activity in the plasma, such as at a sawtooth crash. High resolution charge exchange recombination spectroscopy provided measurement of rotation braking induced by both applied magnetic fields and by magnetohydrodynamic (MHD) instabilities, allowing tests of neoclassical toroidal viscosity theory predictions. Finally, MAST is also equipped with internal and external coils that allow non-axisymmetric fields to be applied for active MHD spectroscopy of instabilities near the no-wall beta limit. MAST has been able to operate above the pressure at which the resonant field amplification is observed to strongly increase. In order to access such high pressures, the resistive wall mode must be damped, and so numerical modelling has focused on assessing the kinetic damping of the mode and its nonlinear interaction with other instabilities. The enhanced understanding of the physical mechanisms driving deleterious MHD activity given by these leading-edge capabilities has provided guidance to optimize operating scenarios for improved plasma performance.

  1. [Lipid networks in mast cell biology].

    PubMed

    Taketomi, Yoshitaka; Murakami, Makoto

    2011-01-01

    Tissue-resident mast cells are derived from circulating committed progenitors, which are originated from pluripotential hematopoietic stem cells in bone marrow. These progenitors migrate into extravascular tissues, where they undergo differentiation and maturation into tissue-specific mature phenotypes. When activated by IgE/antigen, stem cell factor, neuropeptides, or other stimuli, mature mast cells release three classes of biologically active products, including pre-formed mediators stored in secretory granules, newly transcribed cytokines and chemokines, and de novo synthesized lipid mediators. Therefore, these cells have been implicated as major effector cells in acute and chronic inflammatory diseases. In recent years, it has become clear that lipid mediators including arachidonic acid metabolites (prostaglandins and leukotrienes) and lysophospholipid-derived products play crucial roles in mast cell-associated pathology. In this article, we will provide an overview of the roles of various lipid mediators in allergic diseases fueled by studies of their biosynthetic enzymes or receptors. In the latter part, we will make a particular focus on phospholipase A(2) enzymes, which are placed at the bottleneck (rate-limiting) step of the lipid mediator-biosynthetic pathways.

  2. Development of human mast cells in vitro.

    PubMed Central

    Furitsu, T; Saito, H; Dvorak, A M; Schwartz, L B; Irani, A M; Burdick, J F; Ishizaka, K; Ishizaka, T

    1989-01-01

    Nucleated cells of human umbilical cord blood were cocultured with mouse skin-derived 3T3 fibroblasts. After 7-8 weeks in culture, when the number of the other hematopoietic cells declined, metachromatic granule-containing mononuclear cells appeared in the cultures, and the number of the cells increased up to 12 weeks. After 11-14 weeks in culture, the metachromatic mononuclear cells comprised a substantial portion of the cultured cells. These cells contained 1.8-2 micrograms of histamine per 10(6) cells and bore receptors for IgE. All of the cells contained tryptase in their granules. Electron microscopic analysis showed that these cells were mature human mast cells, clearly different from the basophilic granulocytes or eosinophils that arise in a variety of circumstances in cord blood cell cultures. Most of the cultured mast cells expressed some granules with regular crystalline arrays and contained both tryptase and chymase, and thus resembled human skin mast cells. Images PMID:2532357

  3. Regeneration of the immunoglobulin heavy-chain repertoire after transient B-cell depletion with an anti-CD20 antibody

    PubMed Central

    Rouzière, Anne-Sophie; Kneitz, Christian; Palanichamy, Arumugam; Dörner, Thomas; Tony, Hans-Peter

    2005-01-01

    B-cell depletive therapies have beneficial effects in patients suffering from rheumatoid arthritis. Nevertheless, the role of B cells in the pathogenesis of the disease is not clear. In particular, it is not known how the regeneration of the B-cell repertoire takes place. Two patients with active rheumatoid arthritis were treated with rituximab, and the rearranged immunoglobulin heavy-chain genes (Ig-VH) were analysed to follow the B-cell regeneration. Patient A was treated with two courses of rituximab, and B-cell regeneration was followed over 27 months by analysing more than 680 Ig-VH sequences. Peripheral B-cell depletion lasted 7 months and 10 months, respectively, and each time was accompanied by a clinical improvement. Patient B received one treatment course. B-cell depletion lasted 5 months and was accompanied by a good clinical response. B cells regenerated well in both patients, and the repopulated B-cell repertoire was characterised by a polyclonal and diverse use of Ig-VH genes, as expected in adult individuals. During the early phase of B-cell regeneration we observed the expansion and recirculation of a highly mutated B-cell population. These cells expressed very different Ig-VH genes. They were class-switched and could be detected for a short period only. Patient A was followed long term, whereby some characteristic changes in the VH2 family as well as in specific mini-genes like VH3–23, VH 4–34 or VH 1–69 were observed. In addition, rituximab therapy resulted in the loss of clonal B cells for the whole period. Our data show that therapeutic transient B-cell depletion by anti-CD20 antibodies results in the regeneration of a diverse and polyclonal heavy-chain repertoire. During the early phase of B-cell regeneration, highly mutated B cells recirculate for a short time period in both the patients analysed. The longitudinal observation of a single patient up to 27 months shows subtle intraindividual changes, which may indicate repertoire

  4. Potential role of mast cells in hamster cheek pouch carcinogenesis.

    PubMed

    Aromando, Romina F; Pérez, Miguel A; Heber, Elisa M; Trivillin, Verónica A; Tomasi, Víctor H; Schwint, Amanda E; Itoiz, María E

    2008-11-01

    During the process of activation, mast cells release products stored in their granules. Tryptase, a protease released from mast cell granules after activation, induces tumor cell proliferation through the activation of PAR-2 (protease activated receptor 2) on the plasma membrane of carcinoma cells. Chemical cancerization (DMBA) of the hamster cheek pouch is the most accepted model of oral cancer. However, there are no reports on the activation of mast cells during experimental carcinogenesis or on the correlation between mast cell activation and cell proliferation. The aim of the present study was to evaluate the potential effect of mast cells on the proliferation of epithelial cells at different times during the cancerization process. Paraffin serial sections of cancerized, tumor-bearing pouches were stained with Alcian Blue-Safranin to identify the different degrees of mast cell activation. Immunohistochemistry was performed to identify BrdU-positive cells to study tumor cell proliferation. Mast cells were counted and grouped into two categories: inactive mast cells AB-S+++ (red) and active mast cells AB+++S- (blue). Mast cell counts were performed in tumor stroma, base of the tumor (connective tissue immediately below the exophytic tumor), connective and muscle tissue underlying the cancerized epithelium (pouch wall) and adventitious tissue underlying the pouch wall. There was a significant increase in the number of mast cells at the base of tumors (p<0.001) compared to the number of mast cells in the wall of the pouch and in tumor stroma. In normal non-cancerized pouches, inactive mast cells were prevalent both in the wall (AB:S=1:2.15; p<0.001) and in the adventitious tissue (AB:S=1:1.6; p<0.004) of the hamster cheek pouch. At most of the experimental times examined, the ratio of active/inactive mast cells (AB/S) in the wall approximated unity and even reverted. The ratio of mast cells was AB:S 1:1.05 at the base of the tumor and 1:0.24 in tumor stroma (p<0

  5. Augmented mast cell infiltration and microvessel density in prostate cancer

    PubMed Central

    Wagrowska-Danilewicz, Małgorzata; Stasikowska-Kanicka, Olga; Tuka, Elżbieta; Danilewicz, Marian

    2013-01-01

    Aim of the study Recent investigations have taken into account the role of mast cells in prostate cancer formation, analyzing their dual functions (as tumour growth promoters and tumour growth inhibitors). The aim of our study was to compare mast cell infiltration and microvessel density in prostate cancer and in benign prostate hyperplasia. We also attempted to find possible relationships among mast cell infiltration and microvessel density, Gleason score, as well as serum levels of prostate-specific antigen (PSA). Material and methods The investigation was confined to evaluations of material from prostate needle biopsies, carried out in 26 patients with prostate cancer, and of 14 specimens diagnosed as benign hyperplasia. The numbers of tryptase positive mast cells and CD34 positive vessels were determined using a computer image analysis system. In the patients with prostate cancer, both mast cell infiltrates and microvessel density were significantly increased, as compared to the control patients. Results Significant positive correlations were identified between the mean numbers of mast cells and microvessel densities, both in the prostate cancer group and in the control group. Moreover, significant positive correlations were observed between Gleason score on one hand and the number of mast cells and microvessel density on the other. The correlations between PSA serum levels and both mast cell infiltration and microvessel density were positive, but not in a statistically significant way. Conclusions The reported investigations may support the assumption of mast cell promoter function in prostate cancer development, whereas no evidence was found for their opposite PMID:24592126

  6. Mast cells in human and experimental cardiometabolic diseases.

    PubMed

    Shi, Guo-Ping; Bot, Ilze; Kovanen, Petri T

    2015-11-01

    Mast cells, like many other types of inflammatory cell, perform pleiotropic roles in cardiometabolic diseases such as atherosclerosis, abdominal aortic aneurysms, obesity, and diabetes mellitus, as well as complications associated with these diseases. Low numbers of mast cells are present in the heart, aorta, and adipose tissue of healthy humans, but patients with cardiometabolic diseases and animals with experimentally-induced cardiometabolic pathologies have high numbers of mast cells with increased activity in the affected tissues. Mediators released by the activated mast cells, such as chemokines, cytokines, growth factors, heparin, histamine, and proteases, not only function as biomarkers of cardiometabolic diseases, but might also directly contribute to the pathogenesis of such diseases. Mast-cell mediators impede the functions of vascular cells, the integrity of the extracellular matrix, and the activity of other inflammatory cells, thereby contributing to the pathobiology of the conditions at multiple levels. In mouse models, mast-cell activation aggravates the progression of various cardiometabolic pathologies, whereas a genetic deficiency or pharmacological stabilization of mast cells, or depletion or inhibition of specific mast-cell mediators, tends to delay the progression of such conditions. Pharmacological inhibition of mast-cell activation or their targeted effector functions offers potential novel therapeutic strategies for patients with cardiometabolic disorders.

  7. Mast Cells Can Enhance Resistance to Snake and Honeybee Venoms

    NASA Astrophysics Data System (ADS)

    Metz, Martin; Piliponsky, Adrian M.; Chen, Ching-Cheng; Lammel, Verena; Åbrink, Magnus; Pejler, Gunnar; Tsai, Mindy; Galli, Stephen J.

    2006-07-01

    Snake or honeybee envenomation can cause substantial morbidity and mortality, and it has been proposed that the activation of mast cells by snake or insect venoms can contribute to these effects. We show, in contrast, that mast cells can significantly reduce snake-venom-induced pathology in mice, at least in part by releasing carboxypeptidase A and possibly other proteases, which can degrade venom components. Mast cells also significantly reduced the morbidity and mortality induced by honeybee venom. These findings identify a new biological function for mast cells in enhancing resistance to the morbidity and mortality induced by animal venoms.

  8. Overview of physics results from MAST

    SciTech Connect

    Meyer, H.; Maingi, Rajesh

    2009-01-01

    Several improvements to the MAST plant and diagnostics have facilitated new studies advancing the physics basis for ITER and DEMO, as well as for future spherical tokamaks (STs). Using the increased heating capabilities P-NBI <= 3.8 MW H-mode at I-P = 1.2 MA was accessed showing that the energy confinement on MAST scales more weakly with I-P and more strongly with B-t than in the ITER IPB98(y, 2) scaling. Measurements of the fuel retention of shallow pellets extrapolate to an ITER particle throughput of 70% of its original designed total throughput capacity. The anomalous momentum diffusion, chi(phi), is linked to the ion diffusion, chi(i), with a Prandtl number close to P-phi approximate to chi(phi)/chi(i) approximate to 1, although chi(i) approaches neoclassical values. New high spatial resolution measurements of the edge radial electric field, E-r, show that the position of steepest gradients in electron pressure and E-r (i.e. shearing rate) are coincident, but their magnitudes are not linked. The T-e pedestal width on MAST scales with root beta(ped)(pol) rather than rho(pol). The edge localized mode (ELM) frequency for type-IV ELMs, new in MAST, was almost doubled using n = 2 resonant magnetic perturbations from a set of four external coils (n = 1, 2). A new internal 12 coil set (n <= 3) has been commissioned. The filaments in the inter-ELM and L-mode phase are different from ELM filaments, and the characteristics in L-mode agree well with turbulence calculations. A variety of fast particle driven instabilities were studied from 10 kHz saturated fishbone like activity up to 3.8 MHz compressional Alfven eigenmodes. Fast particle instabilities also affect the off-axis NBI current drive, leading to fast ion diffusion of the order of 0.5 m(2) s(-1) and a reduction in the driven current fraction from 40% to 30%. EBW current drive start-up is demonstrated for the first time in a ST generating plasma currents up to 55 kA. Many of these studies contributed to the

  9. Disodium cromoglycate reverses colonic visceral hypersensitivity and influences colonic ion transport in a stress-sensitive rat strain.

    PubMed

    Carroll, Siobhan Yvonne; O'Mahony, Siobhain Mary; Grenham, Susan; Cryan, John Francis; Hyland, Niall Patrick

    2013-01-01

    The interface between psychiatry and stress-related gastrointestinal disorders (GI), such as irritable bowel syndrome (IBS), is well established, with anxiety and depression the most frequently occurring comorbid conditions. Moreover, stress-sensitive Wistar Kyoto (WKY) rats, which display anxiety- and depressive-like behaviors, exhibit GI disturbances akin to those observed in stress-related GI disorders. Additionally, there is mounting preclinical and clinical evidence implicating mast cells as significant contributors to the development of abdominal visceral pain in IBS. In this study we examined the effects of the rat connective tissue mast cell (CTMC) stabiliser, disodium cromoglycate (DSCG) on visceral hypersensitivity and colonic ion transport, and examined both colonic and peritoneal mast cells from stress-sensitive WKY rats. DSCG significantly decreased abdominal pain behaviors induced by colorectal distension in WKY animals independent of a reduction in colonic rat mast cell mediator release. We further demonstrated that mast cell-stimulated colonic ion transport was sensitive to inhibition by the mast cell stabiliser DSCG, an effect only observed in stress-sensitive rats. Moreover, CTMC-like mast cells were significantly increased in the colonic submucosa of WKY animals, and we observed a significant increase in the proportion of intermediate, or immature, peritoneal mast cells relative to control animals. Collectively our data further support a role for mast cells in the pathogenesis of stress-related GI disorders.

  10. Oncogenic Kit signals on endolysosomes and endoplasmic reticulum are essential for neoplastic mast cell proliferation

    PubMed Central

    Obata, Yuuki; Toyoshima, Shota; Wakamatsu, Ei; Suzuki, Shunichi; Ogawa, Shuhei; Esumi, Hiroyasu; Abe, Ryo

    2014-01-01

    Kit is a receptor-type tyrosine kinase found on the plasma membrane. It can transform mast cells through activating mutations. Here, we show that a mutant Kit from neoplastic mast cells from mice, Kit(D814Y), is permanently active and allows cells to proliferate autonomously. It does so by activating two signalling pathways from different intracellular compartments. Mutant Kit from the cell surface accumulates on endolysosomes through clathrin-mediated endocytosis, which requires Kit’s kinase activity. Kit(D814Y) is constitutively associated with phosphatidylinositol 3-kinase, but the complex activates Akt only on the cytoplasmic surface of endolysosomes. It resists destruction because it is under-ubiquitinated. Kit(D814Y) also appears in the endoplasmic reticulum soon after biosynthesis, and there, can activate STAT5 aberrantly. These mechanisms of oncogenic signalling are also seen in rat and human mast cell leukemia cells. Thus, oncogenic Kit signalling occurs from different intracellular compartments, and the mutation acts by altering Kit trafficking as well as activation. PMID:25493654

  11. Release of Elastase from Purified Human Lung Mast Cells and Basophils. Identification as a Hageman Factor Cleaving Enzyme

    DTIC Science & Technology

    1989-01-01

    heterogeneity and hyper- plasia in bleomycin -induced pulmonary fibrosis of rats. Am. Rev. Respir. Dis. 130:.797-902. 40. AGius, R. M., R. C. GoDFREY, and S. T...been shown to be elevated in human pulmonary disorders. Although the HF cleaving assay has been used to demonstrate the presence of functional elastase...FUJLMER, and R. G. CRYSTAL. 1979. Ultrastructure of pulmonary mast cells in patients with fibrotic lung disorders. Lab, Invest. 40-.717-34. 38

  12. Activation of human mast cells by retrocyclin and protegrin highlight their immunomodulatory and antimicrobial properties.

    PubMed

    Gupta, Kshitij; Kotian, Akhil; Subramanian, Hariharan; Daniell, Henry; Ali, Hydar

    2015-10-06

    Preclinical evaluation of Retrocyclins (RC-100, RC-101) and Protegrin-1 (PG-1) antimicrobial peptides (AMPs) is important because of their therapeutic potential against bacterial, fungal and viral infections. Human mast cells (HMCs) play important roles in host defense and wound healing but the abilities of retrocyclins and protegrin-1 to harness these functions have not been investigated. Here, we report that chemically synthesized RC-100 and PG-1 caused calcium mobilization and degranulation in HMCs but these responses were not blocked by an inhibitor of formyl peptide receptor-like 1 (FPRL1), a known receptor for AMPs. However, RC-100 and PG-1 induced degranulation in rat basophilic leukemia (RBL-2H3) cells stably expressing Mas related G protein coupled receptor X2 (MrgX2). Chemical synthesis of these AMPs is prohibitively expensive and post-synthesis modifications (cyclization, disulfide bonds, folding) are inadequate for optimal antimicrobial activity. Indeed, we found that synthetic RC-100, which caused mast cell degranulation via MrgX2, did not display any antimicrobial activity. Green-fluorescent protein (GFP)-tagged RC-101 (analog of RC-100) and GFP-tagged PG-1 purified from transgenic plant chloroplasts killed bacteria and induced mast cell degranulation. Furthermore, GFP-PG1 bound specifically to RBL-2H3 cells expressing MrgX2. These findings suggest that retrocyclins and protegrins activate HMCs independently of FPRL1 but via MrgX2. Harnessing this novel feature of AMPs to activate mast cell's host defense/wound healing properties in addition to their antimicrobial activities expands their clinical potential. Low cost production of AMPs in plants should facilitate their advancement to the clinic overcoming major hurdles in current production systems.

  13. Anti-allergic effects of Lycopus lucidus on mast cell-mediated allergy model

    SciTech Connect

    Shin, Tae-Yong . E-mail: tyshin@woosuk.ac.kr; Kim, Sang-Hyun; Suk, Kyoungho; Ha, Jeoung-Hee; Kim, InKyeom; Lee, Maan-Gee; Jun, Chang-Duk; Kim, Sang-Yong; Lim, Jong-Pil; Eun, Jae-Soon; Shin, Hye-Young; Kim, Hyung-Min

    2005-12-15

    The current study characterizes the mechanism by which the aqueous extract of Lycopus lucidus Turcz. (Labiatae) (LAE) decreases mast cell-mediated immediate-type allergic reaction. The immediate-type allergic reaction is involved in many allergic diseases such as asthma and allergic rhinitis. LAE has been used as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. LAE was anally administered to mice for high and fast absorption. LAE inhibited compound 48/80-induced systemic reactions in mice. LAE decreased the local allergic reaction, passive cutaneous anaphylaxis, activated by anti-dinitrophenyl (DNP) IgE antibody. LAE dose-dependently reduced histamine release from rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE. Furthermore, LAE decreased the secretion of TNF-{alpha} and IL-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated human mast cells. The inhibitory effect of LAE on the pro-inflammatory cytokine was p38 mitogen-activated protein kinase (MAPK) and nuclear factor-{kappa}B (NF-{kappa}B) dependent. LAE attenuated PMA plus A23187-induced degradation of I{kappa}B{alpha} and nuclear translocation of NF-{kappa}B, and specifically blocked activation of p38 MAPK, but not that of c-jun N-terminal kinase and extracellular signal-regulated kinase. Our findings provide evidence that LAE inhibits mast cell-derived immediate-type allergic reactions and involvement of pro-inflammatory cytokines, p38 MAPK, and NF-{kappa}B in these effects.

  14. Activation of human mast cells by retrocyclin and protegrin highlight their immunomodulatory and antimicrobial properties

    PubMed Central

    Gupta, Kshitij; Kotian, Akhil; Subramanian, Hariharan; Daniell, Henry; Ali, Hydar

    2015-01-01

    Preclinical evaluation of Retrocyclins (RC-100, RC-101) and Protegrin-1 (PG-1) antimicrobial peptides (AMPs) is important because of their therapeutic potential against bacterial, fungal and viral infections. Human mast cells (HMCs) play important roles in host defense and wound healing but the abilities of retrocyclins and protegrin-1 to harness these functions have not been investigated. Here, we report that chemically synthesized RC-100 and PG-1 caused calcium mobilization and degranulation in HMCs but these responses were not blocked by an inhibitor of formyl peptide receptor-like 1 (FPRL1), a known receptor for AMPs. However, RC-100 and PG-1 induced degranulation in rat basophilic leukemia (RBL-2H3) cells stably expressing Mas related G protein coupled receptor X2 (MrgX2). Chemical synthesis of these AMPs is prohibitively expensive and post-synthesis modifications (cyclization, disulfide bonds, folding) are inadequate for optimal antimicrobial activity. Indeed, we found that synthetic RC-100, which caused mast cell degranulation via MrgX2, did not display any antimicrobial activity. Green-fluorescent protein (GFP)-tagged RC-101 (analog of RC-100) and GFP-tagged PG-1 purified from transgenic plant chloroplasts killed bacteria and induced mast cell degranulation. Furthermore, GFP-PG1 bound specifically to RBL-2H3 cells expressing MrgX2. These findings suggest that retrocyclins and protegrins activate HMCs independently of FPRL1 but via MrgX2. Harnessing this novel feature of AMPs to activate mast cell's host defense/wound healing properties in addition to their antimicrobial activities expands their clinical potential. Low cost production of AMPs in plants should facilitate their advancement to the clinic overcoming major hurdles in current production systems. PMID:26378047

  15. Effect of selective T cell depletion of host and/or donor bone marrow on lymphopoietic repopulation, tolerance, and graft-vs-host disease in mixed allogeneic chimeras (B10 + B10. D2----B10)

    SciTech Connect

    Ildstad, S.T.; Wren, S.M.; Bluestone, J.A.; Barbieri, S.A.; Stephany, D.; Sachs, D.H.

    1986-01-01

    Reconstitution of lethally irradiated mice with a mixture of T cell-depleted syngeneic plus T cell-depleted allogeneic bone marrow (B10 + B10.D2----B10) leads to the induction of mixed lymphopoietic chimerism, excellent survivals, specific in vivo transplantation tolerance to subsequent donor strain skin grafts, and specific in vitro unresponsiveness to allogeneic donor lymphoid elements as assessed by mixed lymphocyte reaction (MLR) proliferative and cell-mediated lympholysis (CML) cytotoxicity assays. When B10 recipient mice received mixed marrow inocula in which the syngeneic component had not been T cell depleted, whether or not the allogeneic donor marrow was treated, they repopulated exclusively with host-type cells, promptly rejected donor-type skin allografts, and were reactive in vitro to the allogeneic donor by CML and MLR assays. In contrast, T cell depletion of the syngeneic component of the mixed marrow inocula resulted in specific acceptance of allogeneic donor strain skin grafts. Such animals were specifically unreactive to allogeneic donor lymphoid elements in vitro by CML and MLR, but were reactive to third party. When both the syngeneic and allogeneic marrow were T cell depleted, variable percentages of host- and donor-type lymphoid elements were detected in the mixed reconstituted host. When only the syngeneic bone marrow was T cell depleted, animals repopulated exclusively with donor-type cells. Although these animals had detectable in vitro anti-host (B10) reactivity by CML and MLR and reconstituted as fully allogeneic chimeras, they exhibited excellent survival and had no in vivo evidence for graft-vs-host disease. Experiments in which untreated donor spleen cells were added to the inocula in this last group suggest that the presence of T cell-depleted syngeneic bone marrow cells diminishes graft-vs-host disease and the mortality from it.

  16. Contribution of engineered nanomaterials physicochemical properties to mast cell degranulation

    NASA Astrophysics Data System (ADS)

    Johnson, Monica M.; Mendoza, Ryan; Raghavendra, Achyut J.; Podila, Ramakrishna; Brown, Jared M.

    2017-03-01

    The rapid development of engineered nanomaterials (ENMs) has grown dramatically in the last decade, with increased use in consumer products, industrial materials, and nanomedicines. However, due to increased manufacturing, there is concern that human and environmental exposures may lead to adverse immune outcomes. Mast cells, central to the innate immune response, are one of the earliest sensors of environmental insult and have been shown to play a role in ENM-mediated immune responses. Our laboratory previously determined that mast cells are activated via a non-FcεRI mediated response following silver nanoparticle (Ag NP) exposure, which was dependent upon key physicochemical properties. Using bone marrow-derived mast cells (BMMCs), we tested the hypothesis that ENM physicochemical properties influence mast cell degranulation. Exposure to 13 physicochemically distinct ENMs caused a range of mast degranulation responses, with smaller sized Ag NPs (5 nm and 20 nm) causing the most dramatic response. Mast cell responses were dependent on ENMs physicochemical properties such as size, apparent surface area, and zeta potential. Surprisingly, minimal ENM cellular association by mast cells was not correlated with mast cell degranulation. This study suggests that a subset of ENMs may elicit an allergic response and contribute to the exacerbation of allergic diseases.

  17. 127. HYDRAULIC CONTROLS AND GAUGES FOR THE UMBILICAL MAST ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    127. HYDRAULIC CONTROLS AND GAUGES FOR THE UMBILICAL MAST ON UPPER RIGHT SIDE OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. 123. UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    123. UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ON LEFT; HYDRAULIC CONTROL PANEL FOR UMBILICAL MAST AND TRENCH DOORS IN CENTER OF ROOM, FACING WEST. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. 125. HYDRAULIC CONTROLS FOR MAST TRENCH DOORS ON LEFT SIDE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    125. HYDRAULIC CONTROLS FOR MAST TRENCH DOORS ON LEFT SIDE OF HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  20. Contribution of engineered nanomaterials physicochemical properties to mast cell degranulation

    PubMed Central

    Johnson, Monica M.; Mendoza, Ryan; Raghavendra, Achyut J.; Podila, Ramakrishna; Brown, Jared M.

    2017-01-01

    The rapid development of engineered nanomaterials (ENMs) has grown dramatically in the last decade, with increased use in consumer products, industrial materials, and nanomedicines. However, due to increased manufacturing, there is concern that human and environmental exposures may lead to adverse immune outcomes. Mast cells, central to the innate immune response, are one of the earliest sensors of environmental insult and have been shown to play a role in ENM-mediated immune responses. Our laboratory previously determined that mast cells are activated via a non-FcεRI mediated response following silver nanoparticle (Ag NP) exposure, which was dependent upon key physicochemical properties. Using bone marrow-derived mast cells (BMMCs), we tested the hypothesis that ENM physicochemical properties influence mast cell degranulation. Exposure to 13 physicochemically distinct ENMs caused a range of mast degranulation responses, with smaller sized Ag NPs (5 nm and 20 nm) causing the most dramatic response. Mast cell responses were dependent on ENMs physicochemical properties such as size, apparent surface area, and zeta potential. Surprisingly, minimal ENM cellular association by mast cells was not correlated with mast cell degranulation. This study suggests that a subset of ENMs may elicit an allergic response and contribute to the exacerbation of allergic diseases. PMID:28262689

  1. The role of mast cells in allergic inflammation.

    PubMed

    Amin, Kawa

    2012-01-01

    The histochemical characteristics of human basophils and tissue mast cells were described over a century ago by Paul Ehrlich. When mast cells are activated by an allergen that binds to serum IgE attached to their FcɛRI receptors, they release cytokines, eicosanoids and their secretory granules. Mast cells are now thought to exert critical proinflammatory functions, as well as potential immunoregulatory roles, in various immune disorders through the release of mediators such as histamine, leukotrienes, cytokines chemokines, and neutral proteases (chymase and tryptase). The aim of this review is to describe the role of mast cells in allergic inflammation. Mast cells interact directly with bacteria and appear to play a vital role in host defense against pathogens. Drugs, such as glucocorticoids, cyclosporine and cromolyn have been shown to have inhibitory effects on mast cell degranulation and mediator release. This review shows that mast cells play an active role in such diverse diseases as asthma, rhinitis, middle ear infection, and pulmonary fibrosis. In conclusion, mast cells may not only contribute to the chronic airway inflammatory response, remodeling and symptomatology, but they may also have a central role in the initiation of the allergic immune response, that is providing signals inducing IgE synthesis by B-lymphocytes and inducing Th2 lymphocyte differentiation.

  2. Machine Tool Advanced Skills Technology Program (MAST). Overview and Methodology.

    ERIC Educational Resources Information Center

    Texas State Technical Coll., Waco.

    The Machine Tool Advanced Skills Technology Program (MAST) is a geographical partnership of six of the nation's best two-year colleges located in the six states that have about one-third of the density of metals-related industries in the United States. The purpose of the MAST grant is to develop and implement a national training model to overcome…

  3. Marine asset security and tracking (MAST) system

    DOEpatents

    Hanson, Gregory Richard; Smith, Stephen Fulton; Moore, Michael Roy; Dobson, Eric Lesley; Blair, Jeffrey Scott; Duncan, Christopher Allen; Lenarduzzi, Roberto

    2008-07-01

    Methods and apparatus are described for marine asset security and tracking (MAST). A method includes transmitting identification data, location data and environmental state sensor data from a radio frequency tag. An apparatus includes a radio frequency tag that transmits identification data, location data and environmental state sensor data. Another method includes transmitting identification data and location data from a radio frequency tag using hybrid spread-spectrum modulation. Another apparatus includes a radio frequency tag that transmits both identification data and location data using hybrid spread-spectrum modulation.

  4. Space Shuttle Tail Service Mast Concept Verification

    NASA Technical Reports Server (NTRS)

    Uda, R. T.

    1976-01-01

    Design studies and analyses were performed to describe the loads and dynamics of the space shuttle tail service masts (TSMs). Of particular interest are the motion and interaction of the umbilical carrier plate, lanyard system, vacuum jacketed hoses, latches, links, and masthead. A development test rig was designed and fabricated to obtain experimental data. The test program is designed to (1) verify the theoretical dynamics calculations, (2) prove the soundness of design concepts, and (3) elucidate problem areas (if any) in the design of mechanisms and structural components. Design, fabrication, and initiation of TSM development testing at Kennedy Space Center are described.

  5. Chlamydia pneumoniae and atherosclerosis: the role of mast cells.

    PubMed

    Di Pietro, M; Schiavoni, G; Del Piano, M; Shaik, Y; Boscolo, P; Caraffa, A; Grano, M; Teté, S; Conti, F; Sessa, R

    2009-01-01

    Chlamydia pneumoniae (C. pneumoniae), a respiratory pathogen, has been implicated in the pathogenesis of atherosclerosis, an inflammatory progressive disease, characterized by the formation of atherosclerotic plaques. Among several types of inflammatory cells involved in the atherogenesis process, recently particular attention has been directed toward the mast cells. Experimental studies have provided several mechanisms by which C. pneumoniae and mast cells could play a role in all stages of atherosclerosis, from initial inflammatory lesions to plaque rupture. C. pneumoniae, as well as mast cells, may actively participate both through the production of cytokines and matrix-degrading metalloproteinases and by provoking apoptosis of atheroma-associated vascular cells, key events in plaque rupture. This mini-review provides a brief overview on adventitial inflammatory effects of C. pneumoniae and mast cells and their potential role in plaque instability. In addition, in this paper we review the role of mast cells in innate immunity.

  6. Regulation of basophil and mast cell development by transcription factors.

    PubMed

    Sasaki, Haruka; Kurotaki, Daisuke; Tamura, Tomohiko

    2016-04-01

    Basophils and mast cells play important roles in host defense against parasitic infections and allergic responses. Several progenitor populations, either shared or specific, for basophils and/or mast cells have been identified, thus elucidating the developmental pathways of these cells. Multiple transcription factors essential for their development and the relationships between them have been also revealed. For example, IRF8 induces GATA2 expression to promote the generation of both basophils and mast cells. The STAT5-GATA2 axis induces C/EBPα and MITF expression, facilitating the differentiation into basophils and mast cells, respectively. In addition, C/EBPα and MITF mutually suppress each other's expression. This review provides an overview of recent advances in our understanding of how transcription factors regulate the development of basophils and mast cells.

  7. Mast Cells in Lung Homeostasis: Beyond Type I Hypersensitivity.

    PubMed

    Campillo-Navarro, Marcia; Chávez-Blanco, Alma D; Wong-Baeza, Isabel; Serafín-López, Jeanet; Flores-Mejía, Raúl; Estrada-Parra, Sergio; Estrada-García, Iris; Chacón-Salinas, Rommel

    2014-06-01

    Lungs are indispensable organs for the respiratory process, and maintaining their homeostasis is essential for human health and survival. However, during the lifetime of an individual, the lungs suffer countless insults that put at risk their delicate organization and function. Many cells of the immune system participate to maintain this equilibrium and to keep functional lungs. Among these cells, mast cells have recently attracted attention because of their ability to rapidly secrete many chemical and biological mediators that modulate different processes like inflammation, angiogenesis, cell proliferation, etc. In this review, we focus on recent advances in the understanding of the role that mast cells play in lung protection during infections, and of the relation of mast cell responses to type I hypersensitivity-associated pathologies. Furthermore, we discuss the potential role of mast cells during wound healing in the lung and its association with lung cancer, and how mast cells could be exploited as therapeutic targets in some diseases.

  8. A practical method to evaluate radiofrequency exposure of mast workers.

    PubMed

    Alanko, Tommi; Hietanen, Maila

    2008-01-01

    Assessment of occupational exposure to radiofrequency (RF) fields in telecommunication transmitter masts is a challenging task. For conventional field strength measurements using manually operated instruments, it is difficult to document the locations of measurements while climbing up a mast. Logging RF dosemeters worn by the workers, on the other hand, do not give any information about the location of the exposure. In this study, a practical method was developed and applied to assess mast workers' exposure to RF fields and the corresponding location. This method uses a logging dosemeter for personal RF exposure evaluation and two logging barometers to determine the corresponding height of the worker's position on the mast. The procedure is not intended to be used for compliance assessments, but to indicate locations where stricter assessments are needed. The applicability of the method is demonstrated by making measurements in a TV and radio transmitting mast.

  9. Roles and relevance of mast cells in infection and vaccination

    PubMed Central

    Fang, Yu; Xiang, Zou

    2016-01-01

    Abstract In addition to their well-established role in allergy mast cells have been described as contributing to functional regulation of both innate and adaptive immune responses in host defense. Mast cells are of hematopoietic origin but typically complete their differentiation in tissues where they express immune regulatory functions by releasing diverse mediators and cytokines. Mast cells are abundant at mucosal tissues which are portals of entry for common infectious agents in addition to allergens. Here, we review the current understanding of the participation of mast cells in defense against infection. We also discuss possibilities of exploiting mast cell activation to provide adequate adjuvant activity that is needed in high-quality vaccination against infectious diseases. PMID:26565602

  10. The impact of mast cells on cardiovascular diseases.

    PubMed

    Kritikou, Eva; Kuiper, Johan; Kovanen, Petri T; Bot, Ilze

    2016-05-05

    Mast cells comprise an innate immune cell population, which accumulates in tissues proximal to the outside environment and, upon activation, augments the progression of immunological reactions through the release and diffusion of either pre-formed or newly generated mediators. The released products of mast cells include histamine, proteases, as well as a variety of cytokines, chemokines and growth factors, which act on the surrounding microenvironment thereby shaping the immune responses triggered in various diseased states. Mast cells have also been detected in the arterial wall and are implicated in the onset and progression of numerous cardiovascular diseases. Notably, modulation of distinct mast cell actions using genetic and pharmacological approaches highlights the crucial role of this cell type in cardiovascular syndromes. The acquired evidence renders mast cells and their mediators as potential prognostic markers and therapeutic targets in a broad spectrum of pathophysiological conditions related to cardiovascular diseases.

  11. Histamine release from human buffy coat-derived mast cells.

    PubMed

    Wang, Xian Song; Lau, Hang Yung Alaster

    2007-04-01

    Mast cells are unique immune cells that release a spectrum of chemical mediators contributing to the inflammatory symptoms of allergic disorders. Although mast cell biology has been extensively studied in the rodents, research on human mast cells is hampered by the lack of a convenient preparation source. This problem has now been addressed by culturing human mast cells from CD34(+) progenitors. We have recently discovered that human buffy coat preparations from local blood banks are an abundant and convenient source of progenitors for culturing mature mast cells which express functional high affinity IgE receptors and contain histamine and tryptase in their granules. In the current study, we further characterize these buffy coat-derived mast cells by studying their responses to common mast cell secretagogues and stabilizers. Mature human mast cells were obtained by culturing isolated progenitors in methylcellulose containing stem cell factor (SCF), IL-3 and IL-6 for 6 weeks and subsequently in liquid medium containing SCF and IL-6 for another 6 to 8 weeks. Following sensitisation with human IgE, these cells released histamine dose-dependently upon activation by anti-IgE and calcium ionophores while compound 48/80 and substance P were relatively ineffective. When the effects of anti-asthmatic agents on anti-IgE-induced mediator release from these cells were compared, only the beta(2)-adrenoceptor agonists and phosphodiesterase inhibitors produced dose-dependent inhibition but not cromolyn or nedocromil. In total, mast cells cultured from human buffy coat progenitors shared similar functional properties of MC(T) subtype of mast cells found predominantly in human lung parenchyma and intestinal mucosa.

  12. Bone marrow mast cell immunophenotyping in adults with mast cell disease: a prospective study of 33 patients.

    PubMed

    Pardanani, A; Kimlinger, T; Reeder, T; Li, C-Y; Tefferi, A

    2004-08-01

    The aberrant co-expression of CD2 and CD25 antigens is the immunophenotypic hallmark of neoplastic mast cells, and has been consistently identified on bone marrow mast cells from patients with indolent mast cell disease (MCD). We prospectively analyzed the bone marrow mast cell immunophenotype by multiparametric flow cytometry (FC) for 33 MCD cases, to examine the role of CD2 and CD25 expression in establishing diagnosis, detecting histologically occult bone marrow mast cell infiltration, and assessing treatment response. While CD25 was almost uniformly expressed, only 6 of 13 patients with indolent MCD, 1 of 8 with aggressive MCD, 2 of 7 with MCD and an associated hematological disorder, and none of the 2 patients with either mast cell leukemia or smoldering systemic mastocytosis, expressed CD2. One of three patients with cutaneous mastocytosis had an aberrant CD2+/CD25+ mast cell population suggesting histologically occult bone marrow involvement. CD25 expression was lost in one patient who achieved complete histologic remission with therapy, but not in two patients who achieved a partial remission. In conclusion, CD25, but not CD2, is a reliable marker for neoplastic mast cells, and CD25 expression indicates histologically occult bone marrow infiltration and residual disease after therapy.

  13. 2-Hydroxy-3-methoxybenzoic acid attenuates mast cell-mediated allergic reaction in mice via modulation of the FcεRI signaling pathway

    PubMed Central

    Kim, Yeon-Yong; Je, In-Gyu; Kim, Min Jong; Kang, Byeong-Cheol; Choi, Young-Ae; Baek, Moon-Chang; Lee, Byungheon; Choi, Jin Kyeong; Park, Hae Ran; Shin, Tae-Yong; Lee, Soyoung; Yoon, Seung-Bin; Lee, Sang-Rae; Khang, Dongwoo; Kim, Sang-Hyun

    2017-01-01

    Mast cells are important effector cells in immunoglobulin (Ig) E-mediated allergic reactions such as asthma, atopic dermatitis and rhinitis. Vanillic acid, a natural product, has shown anti-oxidant and anti-inflammatory activities. In the present study, we investigated the anti-allergic inflammatory effects of ortho-vanillic acid (2-hydroxy-3-methoxybenzoic acid, o-VA) that was a derivative of vanillic acid isolated from Amomum xanthioides. In mouse anaphylaxis models, oral administration of o-VA (2, 10, 50 mg/kg) dose-dependently attenuated ovalbumin-induced active systemic anaphylaxis and IgE-mediated cutaneous allergic reactions such as hypothermia, histamine release, IgE production and vasodilation; administration of o-VA also suppressed the mast cell degranulator compound 48/80-induced anaphylaxis. In cultured mast cell line RBL-2H3 and isolated rat peritoneal mast cells in vitro, pretreatment with o-VA (1–100 μmol/L) dose-dependently inhibited DNP-HSA-induced degranulation of mast cells by decreasing the intracellular free calcium level, and suppressed the expression of pro-inflammatory cytokines TNF-α and IL-4. Pretreatment of RBL-2H3 cells with o-VA suppressed DNP-HSA-induced phosphorylation of Lyn, Syk, Akt, and the nuclear translocation of nuclear factor-κB. In conclusion, o-VA suppresses the mast cell-mediated allergic inflammatory response by blocking the signaling pathways downstream of high affinity IgE receptor (FcεRI) on the surface of mast cells. PMID:27890918

  14. Adaptor protein-3: A key player in RBL-2H3 mast cell mediator release

    PubMed Central

    da Silva, Elaine Zayas Marcelino; Freitas-Filho, Edismauro Garcia; de Souza-Júnior, Devandir Antonio; daSilva, Luis Lamberti Pinto; Jamur, Maria Celia

    2017-01-01

    Mast cell (MC) secretory granules are Lysosome-Related Organelles (LROs) whose biogenesis is associated with the post-Golgi secretory and endocytic pathways in which the sorting of proteins destined for a specific organelle relies on the recognition of sorting signals by adaptor proteins that direct their incorporation into transport vesicles. The adaptor protein 3 (AP-3) complex mediates protein trafficking between the trans-Golgi network (TGN) and late endosomes, lysosomes, and LROs. AP-3 has a recognized role in LROs biogenesis and regulated secretion in several cell types, including many immune cells such as neutrophils, natural killer cells, and cytotoxic T lymphocytes. However, the relevance of AP-3 for these processes in MCs has not been previously investigated. AP-3 was found to be expressed and distributed in a punctate fashion in rat peritoneal mast cells ex vivo. The rat MC line RBL-2H3 was used as a model system to investigate the role of AP-3 in mast cell secretory granule biogenesis and mediator release. By immunofluorescence and immunoelectron microscopy, AP-3 was localized both to the TGN and early endosomes indicating that AP-3 dependent sorting of proteins to MC secretory granules originates in these organelles. ShRNA mediated depletion of the AP-3 δ subunit was shown to destabilize the AP-3 complex in RBL-2H3 MCs. AP-3 knockdown significantly affected MC regulated secretion of β-hexosaminidase without affecting total cellular enzyme levels. Morphometric evaluation of MC secretory granules by electron microscopy revealed that the area of MC secretory granules in AP-3 knockdown MCs was significantly increased, indicating that AP-3 is involved in MC secretory granule biogenesis. Furthermore, AP-3 knockdown had a selective impact on the secretion of newly formed and newly synthesized mediators. These results show for the first time that AP-3 plays a critical role in secretory granule biogenesis and mediator release in MCs. PMID:28273137

  15. Inebilizumab, a B Cell-Depleting Anti-CD19 Antibody for the Treatment of Autoimmune Neurological Diseases: Insights from Preclinical Studies

    PubMed Central

    Chen, Ding; Gallagher, Sandra; Monson, Nancy L.; Herbst, Ronald; Wang, Yue

    2016-01-01

    Exaggerated or inappropriate responses by B cells are an important feature in many types of autoimmune neurological diseases. The recent success of B-cell depletion in the treatment of multiple sclerosis (MS) has stimulated the development of novel B-cell-targeting therapies with the potential for improved efficacy. CD19 has emerged as a promising target for the depletion of B cells as well as CD19-positive plasmablasts and plasma cells. Inebilizumab (MEDI-551), an anti-CD19 antibody with enhanced antibody-dependent cell-mediated cytotoxicity against B cells, is currently being evaluated in MS and neuromyelitis optica. This review discusses the role of B cells in autoimmune neurological disorders, summarizes the development of inebilizumab, and analyzes the recent results for inebilizumab treatment in an autoimmune encephalitis mouse model. The novel insights obtained from these preclinical studies can potentially guide future investigation of inebilizumab in patients. PMID:27886126

  16. In vitro incubation of bone marrow and peripheral stem cells with vincristine and methylprednisolone: functional T-cell depletion for haploidentical and autologous transplants.

    PubMed

    Fragonas, E; Perticarari, S; Presani, G; Rabusin, M; Andolina, M; Mangiarotti, M A

    2000-11-01

    A mismatched bone marrow transplantation is feasible only if the donor's marrow lymphocytes are eliminated from the graft. This can be achieved by several methods, but all have the disadvantage of inducing a long-lasting immune deficiency while the risk of graft rejection and leukemic relapse increase. We use a sort of functional T-cell depletion by treating the cells with vincristine and methylprednisolone. This method is surely the cheapest and has allowed us to perform 60 transplants with a tolerable risk of GVHD. The treatment of the donor's lymphocytes has already been demonstrated to be able to block the mixed lymphocyte culture reaction in vitro. In this experiment Th1 and Th2 activities were almost completely blocked without reduction of lymphocyte viability and apoptosis induction.

  17. A comparison of murine T-cell-depleted adult bone marrow and full-term fetal blood cells in hematopoietic engraftment and immune reconstitution.

    PubMed

    Chen, Benny J; Cui, Xiuyu; Sempowski, Gregory D; Gooding, Maria E; Liu, Congxiao; Haynes, Barton F; Chao, Nelson J

    2002-01-01

    Umbilical cord blood has been increasingly used as a source of hematopoietic stem cells. A major area of concern for the use of cord blood transplantation is the delay in myeloid and lymphoid recovery. To directly compare myeloid and lymphoid recovery using an animal model of bone marrow and cord blood as sources of stem cells, hematopoietic engraftment and immune recovery were studied following infusion of T-cell-depleted adult bone marrow or full-term fetal blood cells, as a model of cord blood in a murine allogeneic transplantation model (C57BL/6 [H-2(b)] --> BALB/c [H-2(d)]). Allogeneic full-term fetal blood has poorer radioprotective capacity but greater long-term engraftment potential on a cell-to-cell basis compared with T-cell-depleted bone marrow. Allogeneic full-term fetal blood recipients had decreased absolute numbers of T, B, and dendritic cells compared with bone marrow recipients. Splenic T cells in allogeneic full-term fetal blood recipients proliferated poorly, were unable to generate cytotoxic effectors against third-party alloantigens in vitro, and failed to generate alloantigen-specific cytotoxic antibodies in vivo. In addition, reconstituting T cells in fetal blood recipients had decreased mouse T-cell receptor delta single-joint excision circles compared with bone marrow recipients. At a per-cell level, B cells from fetal blood recipients did not proliferate as well as those found in bone marrow recipients. These results suggest that full-term fetal blood can engraft allogeneic hosts across the major histocompatibility barrier with slower hematopoietic engraftment and impaired immune reconstitution.

  18. B cell depletion in HIV-1 subtype A infected Ugandan adults: relationship to CD4 T cell count, viral load and humoral immune responses.

    PubMed

    Oballah, Peter; Flach, Britta; Eller, Leigh A; Eller, Michael A; Ouma, Benson; de Souza, Mark; Kibuuka, Hannah N; Wabwire-Mangen, Fred; Brown, Bruce K; Michael, Nelson L; Robb, Merlin L; Montefiori, David; Polonis, Victoria R

    2011-01-01

    To better understand the nature of B cell dysfunctions in subjects infected with HIV-1 subtype A, a rural cohort of 50 treatment-naïve Ugandan patients chronically infected with HIV-1 subtype A was studied, and the relationship between B cell depletion and HIV disease was assessed. B cell absolute counts were found to be significantly lower in HIV-1+ patients, when compared to community matched negative controls (p<0.0001). HIV-1-infected patients displayed variable functional and binding antibody titers that showed no correlation with viral load or CD4+ T cell count. However, B cell absolute counts were found to correlate inversely with neutralizing antibody (NAb) titers against subtype A (p = 0.05) and subtype CRF02_AG (p = 0.02) viruses. A positive correlation was observed between subtype A gp120 binding antibody titers and NAb breadth (p = 0.02) and mean titer against the 10 viruses (p = 0.0002). In addition, HIV-1 subtype A sera showed preferential neutralization of the 5 subtype A or CRF02_AG pseudoviruses, as compared with 5 pseudoviruses from subtypes B, C or D (p<0.001). These data demonstrate that in patients with chronic HIV-1 subtype A infection, significant B cell depletion can be observed, the degree of which does not appear to be associated with a decrease in functional antibodies. These findings also highlight the potential importance of subtype in the specificity of cross-clade neutralization in HIV-1 infection.

  19. Analysis of TRPV channel activation by stimulation of FCεRI and MRGPR receptors in mouse peritoneal mast cells

    PubMed Central

    Solís-López, A.; Kriebs, U.; Marx, A.; Mannebach, S.; Liedtke, W. B.; Caterina, M. J.; Freichel, M.; Tsvilovskyy, V. V.

    2017-01-01

    The activation of mast cells (MC) is part of the innate and adaptive immune responses and depends on Ca2+ entry across the plasma membrane, leading to the release of preformed inflammatory mediators by degranulation or by de novo synthesis. The calcium conducting channels of the TRPV family, known by their thermo and osmotic sensitivity, have been proposed to be involved in the MC activation in murine, rat, and human mast cell models. So far, immortalized mast cell lines and nonspecific TRPV blockers have been employed to characterize the role of TRPV channels in MC. The aim of this work was to elucidate the physiological role of TRPV channels by using primary peritoneal mast cells (PMCs), a model of connective tissue type mast cells. Our RT-PCR and NanoString analysis identified the expression of TRPV1, TRPV2, and TRPV4 channels in PMCs. For determination of the functional role of the expressed TRPV channels we performed measurements of intracellular free Ca2+ concentrations and beta-hexosaminidase release in PMCs obtained from wild type and mice deficient for corresponding TRPV1, TRPV2 and TRPV4 in response to various receptor-mediated and physical stimuli. Furthermore, substances known as activators of corresponding TRPV-channels were also tested using these assays. Our results demonstrate that TRPV1, TRPV2, and TRPV4 do not participate in activation pathways triggered by activation of the high-affinity receptors for IgE (FcεRI), Mrgprb2 receptor, or Endothelin-1 receptor nor by heat or osmotic stimulation in mouse PMCs. PMID:28158279

  20. Predicted responses of invasive mammal communities to climate-related changes in mast frequency in forest ecosystems.

    PubMed

    Tompkins, Daniel M; Byrom, Andrea E; Pech, Roger P

    2013-07-01

    Predicting the dynamics and impacts of multiple invasive species can be complex because ecological relationships, which occur among several trophic levels, are often incompletely understood. Further, the complexity of these trophic relationships exacerbates our inability to predict climate change effects on invaded ecosystems. We explore the hypothesis that interactions between two global change drivers, invasive vertebrates and climate change, will potentially make matters worse for native biodiversity. In New Zealand beech (Nothofagus spp.) forests, a highly irruptive invasive mammal community is driven by multi-annual resource pulses of beech seed (masting). Because mast frequency is predicted to increase with climate change, we use this as a model system to explore the extent to which such effects may influence invasive vertebrate communities, and the implications of such interactions for native biodiversity and its management. We build on an established model of trophic interactions in the system, combining it with a logistic probability mast function, the parameters of which were altered to simulate either contemporary conditions or conditions of more or less frequent masting. The model predicts that increased mast frequency will lead to populations of a top predator (the stoat) and a mesopredator (the ship rat) becoming less irruptive and being maintained at appreciably higher average abundances in this forest type. In addition, the ability of both current and in-development management approaches to suppress invasive mammals is predicted to be compromised. Because invasive mammals are key drivers of native fauna extinction in New Zealand, with the additional loss of associated functions such as pollination and seed dispersal, these predictions imply potentially serious adverse impacts of climate change for the conservation of biodiversity and ecosystem function. Our study also highlights the importance of long-term monitoring data for assessing and managing

  1. Analysis of TRPV channel activation by stimulation of FCεRI and MRGPR receptors in mouse peritoneal mast cells.

    PubMed

    Solís-López, A; Kriebs, U; Marx, A; Mannebach, S; Liedtke, W B; Caterina, M J; Freichel, M; Tsvilovskyy, V V

    2017-01-01

    The activation of mast cells (MC) is part of the innate and adaptive immune responses and depends on Ca2+ entry across the plasma membrane, leading to the release of preformed inflammatory mediators by degranulation or by de novo synthesis. The calcium conducting channels of the TRPV family, known by their thermo and osmotic sensitivity, have been proposed to be involved in the MC activation in murine, rat, and human mast cell models. So far, immortalized mast cell lines and nonspecific TRPV blockers have been employed to characterize the role of TRPV channels in MC. The aim of this work was to elucidate the physiological role of TRPV channels by using primary peritoneal mast cells (PMCs), a model of connective tissue type mast cells. Our RT-PCR and NanoString analysis identified the expression of TRPV1, TRPV2, and TRPV4 channels in PMCs. For determination of the functional role of the expressed TRPV channels we performed measurements of intracellular free Ca2+ concentrations and beta-hexosaminidase release in PMCs obtained from wild type and mice deficient for corresponding TRPV1, TRPV2 and TRPV4 in response to various receptor-mediated and physical stimuli. Furthermore, substances known as activators of corresponding TRPV-channels were also tested using these assays. Our results demonstrate that TRPV1, TRPV2, and TRPV4 do not participate in activation pathways triggered by activation of the high-affinity receptors for IgE (FcεRI), Mrgprb2 receptor, or Endothelin-1 receptor nor by heat or osmotic stimulation in mouse PMCs.

  2. New insights in mast cell modulation by palmitoylethanolamide.

    PubMed

    De Filippis, D; Negro, L; Vaia, M; Cinelli, M P; Iuvone, T

    2013-02-01

    Since its discovery palmitoylethanolamide was considered as an endogenous compound able to negatively modulate the inflammatory process. Its effects have been extensively investigated in in vitro, in vivo and in clinical studies. Notwithstanding some discrepancy, nowadays the efficacy of palmitoylethanolamide in controlling mast cell behaviour, which likely accounts for its many anti-inflammatory, anti-angiogenic and analgesic effects, is well recognized. In view of their strategic localization at sites directly interfacing with the external environment, mast cells act as surveillance antennae against different types of injury and can undergo activation, thereby regulating both innate and adaptive immune reactions through the release of several preformed and newly synthesized mediators. Mast cells are now viewed as key players in orchestrating several disorders including both acute and chronic inflammatory processes, and have a role in angiogenesis and hyperalgesia. Since mast cells exert also important physiological, homeostatic functions, the most recent goal for pharmacologists is to control, rather than block, mast cell degranulation in order to modulate the pathological scenario. The aim of the present review is to summarise the evidence regarding the role played by palmitoylethanolamide in the control of mast cell activation, starting from in vitro studies, going through in vivo evidence in animal models of disease sustained by mast cell activation, and finally reviewing recent clinical studies using this molecule.

  3. Are Basophils and Mast Cells Masters in HIV Infection?

    PubMed

    Marone, Gianni; Varricchi, Gilda; Loffredo, Stefania; Galdiero, Maria Rosaria; Rivellese, Felice; de Paulis, Amato

    2016-01-01

    The World Health Organization AIDS epidemic update estimates that more than 37 million people are living with HIV infection. Despite the unprecedented success of antiretroviral treatments, significant challenges remain in the fight against HIV. In particular, how uninfected cells capture HIV and transmit virions to target cells remains an unanswered question. Tissue mast cells and peripheral blood basophils can be exposed to virions or HIV products during infection. Several HIV proteins (i.e., envelope glycoproteins gp120 and gp41, Tat, and Nef) can interact with distinct surface receptors expressed by human basophils and mast cells and modulate their functional responses at different levels. Additionally, several groups have provided evidence that human mast cells can be infected in vitro, as well as in vivo, by certain strains of HIV. Recently, it has been demonstrated that basophils purified from healthy donors and intestinal mast cells can efficiently capture HIV on their cell surface and, cocultured with CD4+ T cells, they can transfer the virus to the cocultured cells leading to infection. Direct contact between human basophils or intestinal mast cells and CD4+ T cells can mediate viral trans-infection of T cells through the formation of viral synapses. Thus, basophils and mast cells can provide a cellular basis for capturing and then spreading viruses throughout the body. Collectively, these findings suggest that human basophils and mast cells play a complex and possibly distinct role in HIV infection, warranting further investigations.

  4. Microbes taming mast cells: Implications for allergic inflammation and beyond.

    PubMed

    Forsythe, Paul

    2016-05-05

    There is increasing awareness of a relationship between our microbiota and the pathogenesis of allergy and other inflammatory diseases. In investigating the mechanisms underlying microbiota modulation of allergy the focus has been on the induction phase; alterations in the phenotype and function of antigen presenting cells, induction of regulatory T cells and shifts in Th1/Th2 balance. However there is evidence that microbes can influence the effector phase of disease, specifically that certain potentially beneficial bacteria can attenuate mast cell activation and degranulation. Furthermore, it appears that different non-pathogenic bacteria can utilize distinct mechanisms to stabilize mast cells, acting locally though direct interaction with the mast cell at mucosal sites or attenuating systemic mast cell dependent responses, likely through indirect signaling mechanisms. The position of mast cells on the frontline of defense against pathogens also suggests they may play an important role in fostering the host-microbiota relationship. Mast cells are also conduits of neuro-immuo-endocrine communication, suggesting the ability of microbes to modulate cell responses may have implications for host physiology beyond immunology. Further investigation of mast cell regulation by non-pathogenic or symbiotic bacteria will likely lead to a greater understanding of host microbiota interaction and the role of the microbiome in health and disease.

  5. Changes in numbers and types of mast cell colony-forming cells in the peritoneal cavity of mice after injection of distilled water: evidence that mast cells suppress differentiation of bone marrow-derived precursors

    SciTech Connect

    Kanakura, Y.; Kuriu, A.; Waki, N.; Nakano, T.; Asai, H.; Yonezawa, T.; Kitamura, Y.

    1988-03-01

    Two different types of cells in the peritoneal cavity of mice produce mast cell colonies in methylcellulose. Large mast cell colonies are produced by bone marrow-derived precursors resembling lymphoid cells by light microscopy (L-CFU-Mast), whereas medium and small mast cell colonies are produced by morphologically identifiable mast cells (M-CFU-Mast and S-CFU-Mast, respectively). In the present study we eradicated peritoneal mast cells by intraperitoneal (IP) injection of distilled water. The regeneration process was investigated to clarify the relationship between L-CFU-Mast, M-CFU-Mast, and S-CFU-Mast. After injection of distilled water, M-CFU-Mast and S-CFU-Mast disappeared, but L-CFU-Mast increased, and then M-CFU-Mast and S-CFU-Mast appeared, suggesting the presence of a hierarchic relationship. When purified peritoneal mast cells were injected two days after the water injection, the L-CFU-Mast did not increase. In the peritoneal cavity of WBB6F1-+/+ mice that had been lethally irradiated and rescued by bone marrow cells of C57BL/6-bgJ/bgJ (beige, Chediak-Higashi syndrome) mice, L-CFU-Mast were of bgJ/bgJ type, but M-CFU-Mast and S-CFU-Mast were of +/+ type. The injection of distilled water to the radiation chimeras resulted in the development of bgJ/bgJ-type M-CFU-Mast and then S-CFU-Mast. The presence of mast cells appeared to suppress the recruitment of L-CFU-Mast from the bloodstream and to inhibit the differentiation of L-CFU-Mast to M-CFU-Mast.

  6. Martian environmental simulation for a deployable lattice mast

    NASA Technical Reports Server (NTRS)

    Warden, Robert M.

    1994-01-01

    The Mars Pathfinder mission (formerly Mars Environmental Survey or MESUR) is scheduled for launch in December 1996 and is designed to place a small lander on the surface of Mars. After impact, the lander unfolds to expose its solar panels and release a miniature rover. Also on board is the Imager for Mars Pathfinder (IMP) binocular camera which is elevated by a deployable mast to obtain a panoramic view of the landing area. The design of this deployable mast is based on similar designs which have a long and successful flight history. In the past when this type of self-deployable mast has been used, a rate limiter has been incorporated to control the speed of deployment. In this application, to reduce weight and complexity, it was proposed to eliminate the rate limiter so that the mast would deploy without restraint. Preliminary tests showed that this type of deployment was possible especially if the deployed length was relatively short, as in this application. Compounding the problem, however, was the requirement to deploy the mast at an angle of up to 30 degrees from vertical. The deployment process was difficult to completely analyze due to the effects of gravitational and inertial loads on the mast and camera during rapid extension. Testing in a realistic manner was imperative to verify the system performance. A deployment test was therefore performed to determine the maximum tilt angle at which the mast could reliably extend and support the camera on Mars. The testing of the deployable mast requires partial gravity compensation to simulate the smaller force of Martian gravity. During the test, mass properties were maintained while weight properties were reduced. This paper describes the testing of a deployable mast in a simulated Martian environment as well as the results of the tests.

  7. Self-anchoring mast for deploying a high-speed submersible mixer in a tank

    SciTech Connect

    Cato, Jr., Joseph E.; Shearer, Paul M.; Rodwell, Philip O.

    2004-10-12

    A self-anchoring mast for deploying a high-speed submersible mixer in a tank includes operably connected first and second mast members (20, 22) and a foot member 46 operably connected to the second mast member for supporting the mast in a tank. The second mast member includes a track (36, 38) for slidably receiving a bearing of the mixer to change the orientation of the mixer in the tank.

  8. Self-Anchoring Mast for Deploying a High-Speed Submersible Mixer in a Tank

    SciTech Connect

    Cato, Joseph E. Jr.; Shearer, Paul M.; Rodwell, Philip 0.

    2004-10-12

    A self-anchoring mast for deploying a high-speed submersible mixer in a tank includes operably connected first and second mast members (20, 22) and a foot member 46 operably connected to the second mast member for supporting the mast in a tank. The second mast member includes a track (36, 38) for slidably receiving a bearing of the mixer to change the orientation of the mixer in the tank.

  9. Mast Cell Proteases as Protective and Inflammatory Mediators

    PubMed Central

    Caughey, George H.

    2014-01-01

    Proteases are the most abundant class of proteins produced by mast cells. Many of these are stored in membrane-enclosed intracellular granules until liberated by degranulating stimuli, which include cross-linking of high affinity IgE receptor FcεRI by IgE bound to multivalent allergen. Understanding and separating the functions of the proteases is important because expression differs among mast cells in different tissue locations. Differences between laboratory animals and humans in protease expression also influence the degree of confidence with which results obtained in animal models of mast cell function can be extrapolated to humans. The inflammatory potential of mast cell proteases was the first aspect of their biology to be explored and has received the most attention, in part because some of them—notably tryptases and chymases—are biomarkers of local and systemic mast cell degranulation and anaphylaxis. Although some of the proteases indeed augment allergic inflammation and are potential targets for inhibition to treat asthma and related allergic disorders, they are protective and even anti-inflammatory in some settings. For example, mast cell tryptases may protect from serious bacterial lung infections and may limit the “rubor” component of inflammation caused by vasodilating neuropeptides in the skin. Chymases help to maintain intestinal barrier function and to expel parasitic worms, and may support blood pressure during anaphylaxis by generating angiotensin II. In other life-or-death examples, carboxypeptidase A3 and other mast cell peptidases limit systemic toxicity of endogenous peptides like endothelin and neurotensin during septic peritonitis, and inactivate venom-associated peptides. On the other hand, mast cell peptidase-mediated destruction of protective cytokines, like IL-6, can enhance mortality from sepsis. Peptidases released from mast cells also influence non-mast cell proteases, such as by activating matrix metalloproteinase cascades

  10. Preliminary sizing of vibration absorber for space mast structures

    NASA Technical Reports Server (NTRS)

    Card, M. F.; Mccomb, H. G., Jr.; Peebles, S. W.

    1982-01-01

    A simple method of sizing a vibration absorber for a large, cantilevered flexible mast is presented. The method is based on Den Hartog's vibration absorber theory for two-degree-of-freedom systems. Generalized design curves are presented as well as specific numerical results for a candidate space experiment in which a long flexible antenna mast is attached to the shuttle orbiter and dynamically excited by orbiter accelerations. Results indicate that for large flexible masts, the mass of the vibration absorber required to meet stringent tip deflection tolerances becomes prohibitively large.

  11. Mini-mast CSI testbed user's guide

    NASA Technical Reports Server (NTRS)

    Tanner, Sharon E.; Pappa, Richard S.; Sulla, Jeffrey L.; Elliott, Kenny B.; Miserentino, Robert; Bailey, James P.; Cooper, Paul A.; Williams, Boyd L., Jr.; Bruner, Anne M.

    1992-01-01

    The Mini-Mast testbed is a 20 m generic truss highly representative of future deployable trusses for space applications. It is fully instrumented for system identification and active vibrations control experiments and is used as a ground testbed at NASA-Langley. The facility has actuators and feedback sensors linked via fiber optic cables to the Advanced Real Time Simulation (ARTS) system, where user defined control laws are incorporated into generic controls software. The object of the facility is to conduct comprehensive active vibration control experiments on a dynamically realistic large space structure. A primary goal is to understand the practical effects of simplifying theoretical assumptions. This User's Guide describes the hardware and its primary components, the dynamic characteristics of the test article, the control law implementation process, and the necessary safeguards employed to protect the test article. Suggestions for a strawman controls experiment are also included.

  12. The mechanisms of exocytosis in mast cells.

    PubMed

    Blank, Ulrich

    2011-01-01

    Upon activation through high affinity IgE receptors (FcεRI), mast cells (MCs) can release up to 100% of their content of preformed mediators stored in cytoplasmic secretory granules by compound exocytosis. This causes Type I immediate hypersensitivity reactions and, in the case of inappropriate activation by allergens, the symptoms of allergy. Recent work has uncovered a central role of SNARE (Soluble N-ethylmaleimide-Sensitive Factor (NSF) Attachment Protein (SNAP) Receptors) proteins in regulating the numerous membrane fusion events during exocytosis. This has defined a series of new molecular actors in MC exocytosis that participate in the regulation of membrane fusion and the connection of the fusion machinery with early signaling events. The purpose of this chapter is to describe these proteins and provide a brief overview on their mechanism of action.

  13. Pancam Mast Assembly on Mars Rover

    NASA Technical Reports Server (NTRS)

    Warden, Robert M.; Cross, Mike; Harvison, Doug

    2004-01-01

    The Pancam Mast Assembly (PMA) for the 2003 Mars Rover is a deployable structure that provides an elevated platform for several cameras. The PMA consists of several mechanisms that enable it to raise the cameras as well as point the cameras in all directions. This paper describes the function of the various mechanisms as well as a description of the mechanisms and some test parameters. Designing these mechanisms to operate on the surface of Mars presented several challenges. Typical spacecraft mechanisms must operate in zero-gravity and high vacuum. These mechanisms needed to be designed to operate in Martian gravity and atmosphere. Testing conditions were a little easier because the mechanisms are not required to operate in a vacuum. All of the materials are vacuum compatible, but the mechanisms were tested in a dry nitrogen atmosphere at various cold temperatures.

  14. Immunohistochemical characterization of feline mast cell tumors.

    PubMed

    Mallett, C L; Northrup, N C; Saba, C F; Rodriguez, C O; Rassnick, K M; Gieger, T L; Childress, M O; Howerth, E W

    2013-01-01

    Expression of histamine, serotonin, and KIT was evaluated in 61 archived feline mast cell tumors (MCTs) from the skin (n = 29), spleen (n = 17), and gastrointestinal (GI) tract (n = 15) using immunohistochemistry. Twenty-eight percent of cutaneous MCTs, 18% of splenic MCTs, and 53% of GI MCTs displayed histamine immunoreactivity. Serotonin immunoreactivity was detected in 3 GI and 1 cutaneous MCT. Sixty-nine percent of cutaneous MCTs, 35% of splenic MCTs, and 33% of GI MCTs were positive for KIT. Expression of these biogenic amines and KIT was less common than expected. Results of this study suggest heterogeneity in feline MCTs based on anatomic location. Further studies are needed to explain the significance of these differences.

  15. Novel Identified Receptors on Mast Cells

    PubMed Central

    Migalovich-Sheikhet, Helena; Friedman, Sheli; Mankuta, David; Levi-Schaffer, Francesca

    2012-01-01

    Mast cells (MC) are major participants in the allergic reaction. In addition they possess immunomodulatory roles in the innate and adaptive immune reactions. Their functions are modulated through a number of activating and inhibitory receptors expressed on their surface. This review deals with some of the most recently described receptors, their expression patterns, ligand(s), signal transduction mechanisms, possible cross-talk with other receptors and, last but not least, regulatory functions that the MC can perform based on their receptor expression in health or in disease. Where the receptor role on MC is still not clear, evidences from other hematopoietic cells expressing them is provided as a possible insight for their function on MC. Suggested strategies to modulate these receptors’ activity for the purpose of therapeutic intervention are also discussed. PMID:22876248

  16. Impurity transport driven by fishbones in MAST

    NASA Astrophysics Data System (ADS)

    Cecconello, M.; Jones, O. M.; Garzotti, L.; McClements, K. G.; Carr, M.; Henderson, S. S.; Sharapov, S. E.; Klimek, I.; the MAST Team

    2015-03-01

    In MAST, bursting toroidal Alfvén eigenmodes and fishbones are observed to give rise to an asymmetric perturbation to the soft x-ray (SXR) emission close to the magnetic axis which grows and decays on the time scale of the fishbone evolution. As the fishbone nears its maximum amplitude, the SXR emission starts to increase (decrease) at radial positions smaller (larger) than the radial position of the magnetic axis. This trend in the SXR emission persists for a few milliseconds, until the fishbone starts to decay in amplitude and the slower overall trend of the SXR emission once again becomes dominant. A preliminary analysis suggests that the change in the SXR emission is due to the localized accumulation of high-Z impurities, sustained against parallel transport by the effects of fishbones on the fast ion population.

  17. Impact of stress and mast cells on brain metastases.

    PubMed

    Theoharides, Theoharis C; Rozniecki, Jacek J; Sahagian, Gary; Jocobson, Stanley; Kempuraj, Duraisamy; Conti, Pio; Kalogeromitros, Dimitris

    2008-12-15

    Metastases continue to be the chief cause of morbidity and mortality for many tumors, including brain metastases of lung and mammary adenocarcinoma. Stress appears to increase metastases, but the mechanism is not understood. Recent evidence suggests that local inflammation is conducive for cancer growth and a unique immune cell, the mast cell, accumulates in the stroma surrounding tumors and is critically located at the blood-brain-barrier (BBB). Mast cells express receptors for and can be stimulated by corticotropin-releasing hormone (CRH), secreted under stress, to release mediators such as histamine, IL-8, tryptase and vascular endothelial growth factor (VEGF), which disrupt the BBB permitting metastases. Stress and mast cells could serve as new targets for drug development to prevent brain metastases, especially since CRH receptor antagonists and brain mast cell inhibitors have recently been developed.

  18. Mast cells in allergy and autoimmunity: implications for adaptive immunity.

    PubMed

    Gregory, Gregory D; Brown, Melissa A

    2006-01-01

    As in the fashion industry, trends in a particular area of scientific investigation often are fleeting but then return with renewed and enthusiastic interest. Studies of mast cell biology are good examples of this. Although dogma once relegated mast cells almost exclusively to roles in pathological inflammation associated with allergic disease, these cells are emerging as important players in a number of other physiological processes. Consequently, they are quickly becoming the newest "trendy" cell, both within and outside the field of immunology. As sources of a large array of pro- and anti-inflammatory mediators, mast cells also express cell surface molecules with defined functions in lymphocyte activation and trafficking. Here, we provide an overview of the traditional and newly appreciated contributions of mast cells to both innate and adaptive immune responses.

  19. 19. DECK VIEW LOOKING FORWARD WITH MAST, RIGGING AND BOWSPRIT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. DECK VIEW LOOKING FORWARD WITH MAST, RIGGING AND BOWSPRIT DETAILS - HATCH COVER REMOVED TO SHOW CENTERBOARD TRUNK - KATHRYN-Two-sail Bateau "Skipjack", Dogwood Harbor, Chesapeake Bay, Tilghman, Talbot County, MD

  20. 51. STERN VIEW AFTER CONVERSION TO AFRAME MAST AND NEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. STERN VIEW AFTER CONVERSION TO A-FRAME MAST AND NEW CRANE FOR HOISTING BUOYS. - U.S. Coast Guard Cutter WHITE PINE, U.S. Coast Guard 8th District Base, South Broad Street, Mobile, Mobile County, AL

  1. 47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON LEFT; AIR-CONDITIONER DUCTS ON RIGHT - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  2. Design and Development of the Space Shuttle Tail Service Masts

    NASA Technical Reports Server (NTRS)

    Dandage, S. R.; Herman, N. A.; Godfrey, S. E.; Uda, R. T.

    1977-01-01

    The results of the tail service masts (TSM) concept verification test are presented along with the resulting impact on prototype design. The design criteria are outlined, and the proposed prototype TSM tests are described.

  3. A poloidal section neutron camera for MAST upgrade

    SciTech Connect

    Sangaroon, S.; Weiszflog, M.; Cecconello, M.; Conroy, S.; Ericsson, G.; Wodniak, I.; Keeling, D.; Turnyanskiy, M. [EURATOM Collaboration: MAST Team

    2014-08-21

    The Mega Ampere Spherical Tokamak Upgrade (MAST Upgrade) is intended as a demonstration of the physics viability of the Spherical Tokamak (ST) concept and as a platform for contributing to ITER/DEMO physics. Concerning physics exploitation, MAST Upgrade plasma scenarios can contribute to the ITER Tokamak physics particularly in the field of fast particle behavior and current drive studies. At present, MAST is equipped with a prototype neutron camera (NC). On the basis of the experience and results from previous experimental campaigns using the NC, the conceptual design of a neutron camera upgrade (NC Upgrade) is being developed. As part of the MAST Upgrade, the NC Upgrade is considered a high priority diagnostic since it would allow studies in the field of fast ions and current drive with good temporal and spatial resolution. In this paper, we explore an optional design with the camera array viewing the poloidal section of the plasma from different directions.

  4. Increased Bone Mass in Female Mice Lacking Mast Cell Chymase

    PubMed Central

    Lind, Thomas; Gustafson, Ann-Marie; Calounova, Gabriela; Hu, Lijuan; Rasmusson, Annica; Jonsson, Kenneth B.; Wernersson, Sara; Åbrink, Magnus; Andersson, Göran; Larsson, Sune; Melhus, Håkan; Pejler, Gunnar

    2016-01-01

    Here we addressed the potential impact of chymase, a mast-cell restricted protease, on mouse bone phenotype. We show that female mice lacking the chymase Mcpt4 acquired a persistent expansion of diaphyseal bone in comparison with wild type controls, reaching a 15% larger diaphyseal cross sectional area at 12 months of age. Mcpt4-/- mice also showed increased levels of a bone anabolic serum marker and higher periosteal bone formation rate. However, they were not protected from experimental osteoporosis, suggesting that chymase regulates normal bone homeostasis rather than the course of osteoporosis. Further, the absence of Mcpt4 resulted in age-dependent upregulation of numerous genes important for bone formation but no effects on osteoclast activity. In spite of the latter, Mcpt4-/- bones had increased cortical porosity and reduced endocortical mineralization. Mast cells were found periosteally and, notably, bone-proximal mast cells in Mcpt4-/- mice were degranulated to a larger extent than in wild type mice. Hence, chymase regulates degranulation of bone mast cells, which could affect the release of mast cell-derived factors influencing bone remodelling. Together, these findings reveal a functional impact of mast cell chymase on bone. Further studies exploring the possibility of using chymase inhibitors as a strategy to increase bone volume may be warranted. PMID:27936149

  5. Mast cells: new therapeutic target in helminth immune modulation.

    PubMed

    Vukman, K V; Lalor, R; Aldridge, A; O'Neill, S M

    2016-01-01

    Helminth infection and their secreted antigens have a protective role in many immune-mediated inflammatory disorders such as inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis. However, studies have focused primarily on identifying immune protective mechanisms of helminth infection and their secreted molecules on dendritic cells and macrophages. Given that mast cells have been shown to be implicated in the pathogenesis and progression of many inflammatory disorders, their role should also be examined and considered as cellular target for helminth-based therapies. As there is a dearth of studies examining the interaction of helminth-derived antigens and mast cells, this review will focus on the role of mast cells during helminth infection and examine our current understanding of the involvement of mast cells in TH 1/TH 17-mediated immune disorders. In this context, potential mechanisms by which helminths could target the TH 1/TH 17 promoting properties of mast cells can be identified to unveil novel therapeutic mast cell driven targets in combating these inflammatory disorders.

  6. SNARE complex-mediated degranulation in mast cells.

    PubMed

    Woska, Joseph R; Gillespie, Marc E

    2012-04-01

    Mast cell function and dysregulation is important in the development and progression of allergic and autoimmune disease. Identifying novel proteins involved in mast cell function and disease progression is the first step in the design of new therapeutic strategies. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are a family of proteins demonstrated to mediate the transport and fusion of secretory vesicles to the membrane in mast cells, leading to the subsequent release of the vesicle cargo through an exocytotic mechanism. The functional role[s] of specific SNARE family member complexes in mast cell degranulation has not been fully elucidated. Here, we review recent and historical data on the expression, formation and localization of various SNARE proteins and their complexes in murine and human mast cells. We summarize the functional data identifying the key SNARE family members that appear to participate in mast cell degranulation. Furthermore, we discuss the utilization of RNA interference (RNAi) methods to validate SNARE function and the use of siRNA as a therapeutic approach to the treatment of inflammatory disease. These studies provide an overview of the specific SNARE proteins and complexes that serve as novel targets for the development of new therapies to treat allergic and autoimmune disease.

  7. Carbonic anhydrase enzymes regulate mast cell–mediated inflammation

    PubMed Central

    Soteropoulos, Patricia

    2016-01-01

    Type 2 cytokine responses are necessary for the development of protective immunity to helminth parasites but also cause the inflammation associated with allergies and asthma. Recent studies have found that peripheral hematopoietic progenitor cells contribute to type 2 cytokine–mediated inflammation through their enhanced ability to develop into mast cells. In this study, we show that carbonic anhydrase (Car) enzymes are up-regulated in type 2–associated progenitor cells and demonstrate that Car enzyme inhibition is sufficient to prevent mouse mast cell responses and inflammation after Trichinella spiralis infection or the induction of food allergy–like disease. Further, we used CRISPR/Cas9 technology and illustrate that genetically editing Car1 is sufficient to selectively reduce mast cell development. Finally, we demonstrate that Car enzymes can be targeted to prevent human mast cell development. Collectively, these experiments identify a previously unrecognized role for Car enzymes in regulating mast cell lineage commitment and suggest that Car enzyme inhibitors may possess therapeutic potential that can be used to treat mast cell–mediated inflammation. PMID:27526715

  8. Proton nuclear magnetic resonance studies of mast cell histamine

    SciTech Connect

    Rabenstein, D.L.; Ludowyke, R.; Lagunoff, D.

    1987-11-03

    The state of histamine in mast cells was studied by /sup 1/H NMR spectroscopy. Spectra were measured for histamine in situ in intact mast cells, for histamine in suspensions of mast cell granule matrices that had been stripped of their membranes, and for histamine in solutions of heparin. The /sup 1/H NMR spectrum of intact mast cells is relatively simple, consisting predominantly of resonances for intracellular histamine superimposed on a weaker background of resonances from heparin and proteins of the cells. All of the intracellular histamine contributes of the NMR signals, indicating it must be relatively mobile and not rigidly associated with the negatively charged granule matrix. Spectra for intracellular histamine and for histamine in granule matrices are similar, indicating the latter to be a reasonable model for the in situ situation. The dynamics of binding of histamine by granule matrices and by heparin are considerably different; exchange of histamine between the bulk water and the granule matrices is slow on the /sup 1/H NMR time scale, whereas exchange between the free and bound forms in heparin solution is fast. The chemical shifts of resonances for histamine in mast cells are pH dependent, decreasing as the intragranule pH increases without splitting or broadening. The results are interpreted to indicate that histamine in mast cells is relatively labile, with rapid exchange between histamine and pools of free histamine in water compartments confined in the granule matrix.

  9. Dermal mast cell responses in Paragonimus westermani-infected mice.

    PubMed

    Shin, M H

    1997-12-01

    This study was carried out to determine whether dermal mast cell responses to Paragonimus westermani in an abnormal host, the mouse, were dependent on the site of metacercarial inoculation. In mice during subcutaneous infection, the number of dermal mast cells were increased significantly (p < 0.05) at the first week (38.3/mm2) and then persisted at a high level until the sixth week (45.2/mm2) of infection compared with PBS-injected (control) mice (range: 19.4-25.1/mm2). In mice during oral infection, the number of dermal mast cells were increased significantly (p < 0.05) at two weeks (33.5/mm2) after infection and remained at these levels thereafter compared with non-infected (control) mice (range: 17.4-22.3/mm2). In mice both during subcutaneous and oral infection, the recruited dermal mast cells showed extensive degranulation at the second week (68.4% and 60.7%, respectively), reached a peak at the third week (81.4%, and 92.1%, respectively) and then declined slightly thereafter. By contrast, in both control mice, about 10% of dermal mast cells were degranulated. In conclusion, this study suggests that dermal mast cell responses to P. westermani in mice are dependent on cutaneous sensitization by larval excretory-secretory antigens, irrespective of infection route.

  10. Thrombomodulin inhibits the activation of eosinophils and mast cells.

    PubMed

    Roeen, Ziaurahman; Toda, Masaaki; D'Alessandro-Gabazza, Corina N; Onishi, Masahiro; Kobayashi, Tetsu; Yasuma, Taro; Urawa, Masahito; Taguchi, Osamu; Gabazza, Esteban C

    2015-01-01

    Eosinophils and mast cells play critical roles in the pathogenesis of bronchial asthma. Activation of both cells leads to the release of pro-inflammatory mediators in the airway of asthmatic patients. Recently, we have shown that inhaled thrombomodulin inhibits allergic bronchial asthma in a mouse model. In the present study, we hypothesize that thrombomodulin can inhibit the activation of eosinophils and mast cells. The effect of thrombomodulin on the activation and release of inflammatory mediators from eosinophils and mast cells was evaluated. Thrombomodulin inhibited the eotaxin-induced chemotaxis, upregulation of CD11b and degranulation of eosinophils. Treatment with thrombomodulin also significantly suppressed the degranulation and synthesis of inflammatory cytokines and chemokines in eosinophils and mast cells. Mice treated with a low-dose of inhaled thrombomodulin have decreased number of eosinophils and activated mast cells and Th2 cytokines in the lungs compared to untreated mice. The results of this study suggest that thrombomodulin may modulate allergic responses by inhibiting the activation of both eosinophils and mast cells.

  11. Mast cells protect against Pseudomonas aeruginosa-induced lung injury.

    PubMed

    Junkins, Robert D; Carrigan, Svetlana O; Wu, Zhengli; Stadnyk, Andrew W; Cowley, Elizabeth; Issekutz, Thomas; Berman, Jason; Lin, Tong-Jun

    2014-08-01

    Pseudomonas aeruginosa, an opportunistic pathogen, is the leading cause of morbidity and mortality in immune-compromised individuals. Maintaining the integrity of the respiratory epithelium is critical for an effective host response to P. aeruginosa. Given the close spatial relationship between mast cells and the respiratory epithelium, and the importance of tightly regulated epithelial permeability during lung infections, we examined whether mast cells influence airway epithelial integrity during P. aeruginosa lung infection in a mouse model. We found that mast cell-deficient Kit(W-sh)/Kit(W-sh) mice displayed greatly increased epithelial permeability, bacterial dissemination, and neutrophil accumulation compared with wild-type animals after P. aeruginosa infection; these defects were corrected on reconstitution with mast cells. An in vitro Transwell co-culture model further demonstrated that a secreted mast cell factor decreased epithelial cell apoptosis and tumor necrosis factor production after P. aeruginosa infection. Together, our data demonstrate a previously unrecognized role for mast cells in the maintenance of epithelial integrity during P. aeruginosa infection, through a mechanism that likely involves prevention of epithelial apoptosis and tumor necrosis factor production. Our understanding of mechanisms of the host response to P. aeruginosa will open new avenues for the development of successful preventative and treatment strategies.

  12. Induction of dexamethasone (DM) of histidine decarboxylase (HDC) in mast cells

    SciTech Connect

    Ichikawa, A.; Imanishi, N.; Nakayama, T.; Asano, M.; Tomita, K.

    1986-05-01

    Effects of glucocorticoids on HDC in cultured mouse mastocytoma P-815 cells and rat peritoneal mast cells (RPMC) were investigated to explore the role of steroids in inflammatory tissues. DM (1 nM to 10 ..mu..M) significantly elevated the histamine content and HDC activity of P-815 cells (37/sup 0/C, 24 hrs), accompanying with a growth retardation of the cells by about 40%. In contrast to histamine, serotonin levels of P-815 cells were decreased by treatment with DM. However, DM had no significant effects on the activities of various enzymes other than HDC present in granules or membrane of P-815 cells. DM-induced increases of histamine and HDC activity were completely suppressed by the addition of cycloheximide and actinomycin D. P-815 cells were found to have the binding sites for /sup 3/H-DM in the cytosol (Kd=2.2 nM, 450 sites/cell) and in the nuclei (Kd=0.1 nM, 39 sites/nucleus). Purified HDC from P-815 cells was identified to be an isozyme of mast cell type enzyme (MW=110K, pI=5.4). In contrast, the basal histamine level of cultured RPMC was not affected by treatment of DM, which suppressed histamine release activity induced by DNP-ascaris antiserum by 40%-50%. Histamine-depleted RPMC after degranulation partially recovered histamine level by 50%-60% in the presence of DM. These results showed that glucocorticoids specifically stimulated histamine formation with the increased de novo synthesis of HDC in mast cells.

  13. Subthreshold IKK activation modulates the effector functions of primary mast cells and allows specific targeting of transformed mast cells.

    PubMed

    Drube, Sebastian; Weber, Franziska; Loschinski, Romy; Beyer, Mandy; Rothe, Mandy; Rabenhorst, Anja; Göpfert, Christiane; Meininger, Isabel; Diamanti, Michaela A; Stegner, David; Häfner, Norman; Böttcher, Martin; Reinecke, Kirstin; Herdegen, Thomas; Greten, Florian R; Nieswandt, Bernhard; Hartmann, Karin; Krämer, Oliver H; Kamradt, Thomas

    2015-03-10

    Mast cell differentiation and proliferation depends on IL-3. IL-3 induces the activation of MAP-kinases and STATs and consequently induces proliferation and survival. Dysregulation of IL-3 signaling pathways also contribute to inflammation and tumorigenesis. We show here that IL-3 induces a SFK- and Ca²⁺-dependent activation of the inhibitor of κB kinases 2 (IKK2) which results in mast cell proliferation and survival but does not induce IκBα-degradation and NFκB activation. Therefore we propose the term "subthreshold IKK activation".This subthreshold IKK activation also primes mast cells for enhanced responsiveness to IL-33R signaling. Consequently, co-stimulation with IL-3 and IL-33 increases IKK activation and massively enhances cytokine production induced by IL-33.We further reveal that in neoplastic mast cells expressing constitutively active Ras, subthreshold IKK activation is associated with uncontrolled proliferation. Consequently, pharmacological IKK inhibition reduces tumor growth selectively by inducing apoptosis in vivo.Together, subthreshold IKK activation is crucial to mediate the full IL-33-induced effector functions in primary mast cells and to mediate uncontrolled proliferation of neoplastic mast cells. Thus, IKK2 is a new molecularly defined target structure.

  14. Subthreshold IKK activation modulates the effector functions of primary mast cells and allows specific targeting of transformed mast cells

    PubMed Central

    Drube, Sebastian; Beyer, Mandy; Rothe, Mandy; Rabenhorst, Anja; Göpfert, Christiane; Meininger, Isabel; Diamanti, Michaela A.; Stegner, David; Häfner, Norman; Böttcher, Martin; Reinecke, Kirstin; Herdegen, Thomas; Greten, Florian R.; Nieswandt, Bernhard; Hartmann, Karin; Krämer, Oliver H.; Kamradt, Thomas

    2015-01-01

    Mast cell differentiation and proliferation depends on IL-3. IL-3 induces the activation of MAP-kinases and STATs and consequently induces proliferation and survival. Dysregulation of IL-3 signaling pathways also contribute to inflammation and tumorigenesis. We show here that IL-3 induces a SFK- and Ca2+-dependent activation of the inhibitor of κB kinases 2 (IKK2) which results in mast cell proliferation and survival but does not induce IκBα-degradation and NFκB activation. Therefore we propose the term “subthreshold IKK activation”. This subthreshold IKK activation also primes mast cells for enhanced responsiveness to IL-33R signaling. Consequently, co-stimulation with IL-3 and IL-33 increases IKK activation and massively enhances cytokine production induced by IL-33. We further reveal that in neoplastic mast cells expressing constitutively active Ras, subthreshold IKK activation is associated with uncontrolled proliferation. Consequently, pharmacological IKK inhibition reduces tumor growth selectively by inducing apoptosis in vivo. Together, subthreshold IKK activation is crucial to mediate the full IL-33-induced effector functions in primary mast cells and to mediate uncontrolled proliferation of neoplastic mast cells. Thus, IKK2 is a new molecularly defined target structure. PMID:25749030

  15. Inhibitory Effect of Carotenoids on the Degranulation of Mast Cells via Suppression of Antigen-induced Aggregation of High Affinity IgE Receptors*

    PubMed Central

    Sakai, Shota; Sugawara, Tatsuya; Matsubara, Kiminori; Hirata, Takashi

    2009-01-01

    Carotenoids have been demonstrated to possess antioxidative and anti-inflammatory effects. However, there is no report that the effects of carotenoids on degranulation of mast cell is critical for type I allergy. In this study, we focused on the effect of carotenoids on antigen-induced degranulation of mast cells. Fucoxanthin, astaxanthin, zeaxanthin, and β-carotene significantly inhibited the antigen-induced release of β-hexosaminidase in rat basophilic leukemia 2H3 cells and mouse bone marrow-derived mast cells. Those carotenoids also inhibited antigen-induced aggregation of the high affinity IgE receptor (FcϵRI), which is the most upstream of the degranulating signals of mast cells. Furthermore, carotenoids inhibited FcϵRI-mediated intracellular signaling, such as phosphorylation of Lyn kinase and Fyn kinase. It suggests that the inhibitory effect of carotenoids on the degranulation of mast cells were mainly due to suppressing the aggregation of FcϵRI followed by intracellular signaling. In addition, those carotenoids inhibited antigen-induced translocation of FcϵRI to lipid rafts, which are known as platforms of the aggregation of FcϵRI. We assume that carotenoids may modulate the function of lipid rafts and inhibit the translocation of FcϵRI to lipid rafts. This is the first report that focused on the aggregation of FcϵRI to investigate the mechanism of the inhibitory effects on the degranulation of mast cells and evaluated the functional activity of carotenoids associated with lipid rafts. PMID:19700409

  16. Mastocytosis: immunophenotypical features of the transformed mast cells are unique among hematopoietic cells.

    PubMed

    Horny, Hans-Peter; Sotlar, Karl; Valent, Peter

    2014-05-01

    Mastocytosis is a disease of bone marrow origin histologically characterized by compact tissue infiltrates of atypical mast cells never seen in reactive states. Most patients with mastocytosis have transformed mast cells carrying an activating point mutation at codon 816 of KIT and also show an elevated serum tryptase level. In this article immunophenotypical features of mast cells are described. Based on these features, mast cells are not closely related to other myeloid cells. Using the knowledge on aberrantly expressed antigens by mast cells, the hematopathologist should be able to recognize the disease even in the presence of unusual morphologic findings or an associated hematologic non-mast cell lineage disease.

  17. Overview of physics results from MAST towards ITER/DEMO and the MAST Upgrade

    NASA Astrophysics Data System (ADS)

    Meyer, H.; Abel, I. G.; Akers, R. J.; Allan, A.; Allan, S. Y.; Appel, L. C.; Asunta, O.; Barnes, M.; Barratt, N. C.; Ben Ayed, N.; Bradley, J. W.; Canik, J.; Cahyna, P.; Cecconello, M.; Challis, C. D.; Chapman, I. T.; Ciric, D.; Colyer, G.; Conway, N. J.; Cox, M.; Crowley, B. J.; Cowley, S. C.; Cunningham, G.; Danilov, A.; Darke, A.; De Bock, M. F. M.; De Temmerman, G.; Dendy, R. O.; Denner, P.; Dickinson, D.; Dnestrovsky, A. Y.; Dnestrovsky, Y.; Driscoll, M. D.; Dudson, B.; Dunai, D.; Dunstan, M.; Dura, P.; Elmore, S.; Field, A. R.; Fishpool, G.; Freethy, S.; Fundamenski, W.; Garzotti, L.; Ghim, Y. C.; Gibson, K. J.; Gryaznevich, M. P.; Harrison, J.; Havlíčková, E.; Hawkes, N. C.; Heidbrink, W. W.; Hender, T. C.; Highcock, E.; Higgins, D.; Hill, P.; Hnat, B.; Hole, M. J.; Horáček, J.; Howell, D. F.; Imada, K.; Jones, O.; Kaveeva, E.; Keeling, D.; Kirk, A.; Kočan, M.; Lake, R. J.; Lehnen, M.; Leggate, H. J.; Liang, Y.; Lilley, M. K.; Lisgo, S. W.; Liu, Y. Q.; Lloyd, B.; Maddison, G. P.; Mailloux, J.; Martin, R.; McArdle, G. J.; McClements, K. G.; McMillan, B.; Michael, C.; Militello, F.; Molchanov, P.; Mordijck, S.; Morgan, T.; Morris, A. W.; Muir, D. G.; Nardon, E.; Naulin, V.; Naylor, G.; Nielsen, A. H.; O'Brien, M. R.; O'Gorman, T.; Pamela, S.; Parra, F. I.; Patel, A.; Pinches, S. D.; Price, M. N.; Roach, C. M.; Robinson, J. R.; Romanelli, M.; Rozhansky, V.; Saarelma, S.; Sangaroon, S.; Saveliev, A.; Scannell, R.; Seidl, J.; Sharapov, S. E.; Schekochihin, A. A.; Shevchenko, V.; Shibaev, S.; Stork, D.; Storrs, J.; Sykes, A.; Tallents, G. J.; Tamain, P.; Taylor, D.; Temple, D.; Thomas-Davies, N.; Thornton, A.; Turnyanskiy, M. R.; Valovič, M.; Vann, R. G. L.; Verwichte, E.; Voskoboynikov, P.; Voss, G.; Warder, S. E. V.; Wilson, H. R.; Wodniak, I.; Zoletnik, S.; Zagôrski, R.; MAST, the; NBI Teams

    2013-10-01

    New diagnostic, modelling and plant capability on the Mega Ampère Spherical Tokamak (MAST) have delivered important results in key areas for ITER/DEMO and the upcoming MAST Upgrade, a step towards future ST devices on the path to fusion currently under procurement. Micro-stability analysis of the pedestal highlights the potential roles of micro-tearing modes and kinetic ballooning modes for the pedestal formation. Mitigation of edge localized modes (ELM) using resonant magnetic perturbation has been demonstrated for toroidal mode numbers n = 3, 4, 6 with an ELM frequency increase by up to a factor of 9, compatible with pellet fuelling. The peak heat flux of mitigated and natural ELMs follows the same linear trend with ELM energy loss and the first ELM-resolved Ti measurements in the divertor region are shown. Measurements of flow shear and turbulence dynamics during L-H transitions show filaments erupting from the plasma edge whilst the full flow shear is still present. Off-axis neutral beam injection helps to strongly reduce the redistribution of fast-ions due to fishbone modes when compared to on-axis injection. Low-k ion-scale turbulence has been measured in L-mode and compared to global gyro-kinetic simulations. A statistical analysis of principal turbulence time scales shows them to be of comparable magnitude and reasonably correlated with turbulence decorrelation time. Te inside the island of a neoclassical tearing mode allow the analysis of the island evolution without assuming specific models for the heat flux. Other results include the discrepancy of the current profile evolution during the current ramp-up with solutions of the poloidal field diffusion equation, studies of the anomalous Doppler resonance compressional Alfvén eigenmodes, disruption mitigation studies and modelling of the new divertor design for MAST Upgrade. The novel 3D electron Bernstein synthetic imaging shows promising first data sensitive to the edge current profile and flows.

  18. Effects of in vivo injection of anti-chicken CD25 monoclonal antibody on regulatory T cell depletion and CD4+CD25- T cell properties in chickens.

    PubMed

    Shanmugasundaram, Revathi; Selvaraj, Ramesh K

    2012-03-01

    Regulatory T cells (Tregs) are defined as CD4(+)CD25(+) cells in chickens. This study examined the effects of an anti-chicken CD25 monoclonal antibody injection (0.5 mg/bird) on in vivo depletion of Tregs and the properties of CD4(+)CD25(-) cells in Treg-depleted birds. The CD4(+)CD25(+) cell percentage in the blood was lower at 8 d post injection than at 0 d. Anti-CD25-mediated CD4(+)CD25(+) cell depletion in blood was maximum at 12 d post injection. The anti-CD25 antibody injection depleted CD4(+)CD25(+) cells in the spleen and cecal tonsils, but not in the thymus, at 12 d post antibody injection. CD4(+)CD25(-) cells from the spleen and cecal tonsils of birds injected with the anti-chicken CD25 antibody had higher proliferation and higher IL-2 and IFNγ mRNA amounts than the controls at 12 d post injection. At 20 d post injection, CD4(+)CD25(+) cell percentages in the blood, spleen and thymus were comparable to that of the 0 d post injection. It could be concluded that anti-chicken CD25 injection temporarily depleted Treg population and increased and IL-2 and IFNγ mRNA amounts in CD4(+)CD25(-) cells at 12d post injection.

  19. Pegylated G-CSF Inhibits Blood Cell Depletion, Increases Platelets, Blocks Splenomegaly, and Improves Survival after Whole-Body Ionizing Irradiation but Not after Irradiation Combined with Burn

    PubMed Central

    Kiang, Juliann G.; Zhai, Min; Liao, Pei-Jyun; Bolduc, David L.; Elliott, Thomas B.; Gorbunov, Nikolai V.

    2014-01-01

    Exposure to ionizing radiation alone (radiation injury, RI) or combined with traumatic tissue injury (radiation combined injury, CI) is a crucial life-threatening factor in nuclear and radiological accidents. As demonstrated in animal models, CI results in greater mortality than RI. In our laboratory, we found that B6D2F1/J female mice exposed to 60Co-γ-photon radiation followed by 15% total-body-surface-area skin burns experienced an increment of 18% higher mortality over a 30-day observation period compared to irradiation alone; that was accompanied by severe cytopenia, thrombopenia, erythropenia, and anemia. At the 30th day after injury, neutrophils, lymphocytes, and platelets still remained very low in surviving RI and CI mice. In contrast, their RBC, hemoglobin, and hematocrit were similar to basal levels. Comparing CI and RI mice, only RI induced splenomegaly. Both RI and CI resulted in bone marrow cell depletion. It was observed that only the RI mice treated with pegylated G-CSF after RI resulted in 100% survival over the 30-day period, and pegylated G-CSF mitigated RI-induced body-weight loss and depletion of WBC and platelets. Peg-G-CSF treatment sustained RBC balance, hemoglobin levels, and hematocrits and inhibited splenomegaly after RI. The results suggest that pegylated G-CSF effectively sustained animal survival by mitigating radiation-induced cytopenia, thrombopenia, erythropenia, and anemia. PMID:24738019

  20. Gender difference in bone metastasis of human small cell lung cancer, SBC-5 cells in natural killer-cell depleted severe combined immunodeficient mice.

    PubMed

    Sakaguchi, Satoshi; Goto, Hisatsugu; Hanibuchi, Masaki; Otsuka, Shinsaku; Ogino, Hirokazu; Kakiuchi, Soji; Uehara, Hisanori; Yano, Seiji; Nishioka, Yasuhiko; Sone, Saburo

    2010-05-01

    Lung cancer frequently develops multiple organ metastases, which thus makes this disease a leading cause of malignancy-related death worldwide. A gender difference is reported to affect the incidence and mortality of lung cancer; however, whether and how the gender difference is involved in lung cancer metastasis is unclear. This study evaluated the gender difference in multiple organ metastases in human small cell lung cancer (SBC-5) cells by using natural killer cell-depleted severe combined immunodeficient mice. Among multiple organ metastases, only bone metastasis formation significantly increased in female mice in comparison to males, while no significant difference was observed in the metastases to the liver and lungs. The suppression of androgen by castration or androgen receptor antagonist treatment in male mice also induced a significant increase of bone metastases. The number of osteoclasts in the bone metastatic lesions was greater in female mice and in mice with androgen suppression than in control male. However, there was no significant difference in the serum concentration of parathyroid hormone-related protein (PTHrP) associated with gender or androgen suppression. An in vitro study also indicated that sex steroid treatment had no effect on the proliferation or PTHrP production in SBC-5 cells. These results indicate that the balance of sex steroids therefore plays an important role in the formation of bone metastasis in small cell lung cancer, and suggests diverse mechanisms of interaction between cancer cells and host cells in the bone microenvironment.

  1. Regulatory T-cell depletion in the gut caused by integrin β7 deficiency exacerbates DSS colitis by evoking aberrant innate immunity.

    PubMed

    Zhang, H L; Zheng, Y J; Pan, Y D; Xie, C; Sun, H; Zhang, Y H; Yuan, M Y; Song, B L; Chen, J F

    2016-03-01

    Integrin α4β7 controls lymphocyte trafficking into the gut and has essential roles in inflammatory bowel disease (IBD). The α4β7-blocking antibody vedolizumab is approved for IBD treatment; however, high dose of vedolizumab aggravates colitis in a small percentage of patients. Herein, we show that integrin β7 deficiency results in colonic regulatory T (Treg) cell depletion and exacerbates dextran sulfate sodium (DSS) colitis by evoking aberrant innate immunity. In DSS-treated β7-deficient mice, the loss of colonic Treg cells induces excessive macrophage infiltration in the colon via upregulation of colonic epithelial intercellular adhesion molecule 1 and increases proinflammatory cytokine expression, thereby exacerbating DSS-induced colitis. Moreover, reconstitution of the colonic Treg cell population in β7-deficient mice suppresses aberrant innate immune response in the colon and attenuates DSS colitis. Thus, integrin α4β7 is essential for suppression of DSS colitis as it regulates the colonic Treg cell population and innate immunity.

  2. T-cell depleted allogeneic hematopoietic cell transplants as a platform for adoptive therapy with leukemia selective or virus-specific T-cells.

    PubMed

    O'Reilly, R J; Koehne, G; Hasan, A N; Doubrovina, E; Prockop, S

    2015-06-01

    Allogeneic hematopoietic cell transplants adequately depleted of T-cells can reduce or prevent acute and chronic GVHD in both HLA-matched and haplotype-disparate hosts, without post-transplant prophylaxis with immunosuppressive drugs. Recent trials indicate that high doses of CD34+ progenitors from G-CSF mobilized peripheral blood leukocytes isolated and T-cell depleted by immunoadsorption to paramagnetic beads, when administered after myeloablative conditioning with TBI and chemotherapy or chemotherapy alone can secure consistent engraftment and abrogate GVHD in patients with acute leukemia without incurring an increased risk of a recurrent leukemia. Early clinical trials also indicate that high doses of in vitro generated leukemia-reactive donor T-cells can be adoptively transferred and can induce remissions of leukemia relapse without GVHD. Similarly, virus-specific T-cells generated from the transplant donor or an HLA partially matched third party, have induced remissions of Rituxan-refractory EBV lymphomas and can clear CMV disease or viremia persisting despite antiviral therapy in a high proportion of cases. Analyses of treatment responses and failures illustrate both the advantages and limitations of donor or banked, third party-derived T-cells, but underscore the potential of adoptive T-cell therapy in the absence of ongoing immunosuppression.

  3. Molecular hydrogen suppresses FcepsilonRI-mediated signal transduction and prevents degranulation of mast cells.

    PubMed

    Itoh, Tomohiro; Fujita, Yasunori; Ito, Mikako; Masuda, Akio; Ohno, Kinji; Ichihara, Masatoshi; Kojima, Toshio; Nozawa, Yoshinori; Ito, Masafumi

    2009-11-27

    Molecular hydrogen ameliorates oxidative stress-associated diseases in animal models. We found that oral intake of hydrogen-rich water abolishes an immediate-type allergic reaction in mice. Using rat RBL-2H3 mast cells, we demonstrated that hydrogen attenuates phosphorylation of the FcepsilonRI-associated Lyn and its downstream signal transduction, which subsequently inhibits the NADPH oxidase activity and reduces the generation of hydrogen peroxide. We also found that inhibition of NADPH oxidase attenuates phosphorylation of Lyn in mast cells, indicating the presence of a feed-forward loop that potentiates the allergic responses. Hydrogen accordingly inhibits all tested signaling molecule(s) in the loop. Hydrogen effects have been solely ascribed to exclusive removal of hydroxyl radical. In the immediate-type allergic reaction, hydrogen exerts its beneficial effect not by its radical scavenging activity but by modulating a specific signaling pathway. Effects of hydrogen in other diseases are possibly mediated by modulation of yet unidentified signaling pathways. Our studies also suggest that hydrogen is a gaseous signaling molecule like nitric oxide.

  4. Intestinal and peritoneal mast cells differ in kinetics of quantal release.

    PubMed

    Balseiro-Gomez, Santiago; Ramirez-Ponce, M Pilar; Acosta, Jorge; Ales, Eva; Flores, Juan A

    2016-01-15

    5-hydroxytriptamine (5-HT, serotonin) storage and release in mast cell (MC) secretory granules (SG) are dependent on serglycin proteoglycans (PG). This notion is based on the studies of MC of the connective tissue subtype that predominantly contain PG of the heparin type, whereas intestinal mucosal MC, which contain predominantly chondroitin sulfate, have been poorly explored. In the present study, we addressed the possibility that PG contents may differently affect the storage and release of preformed mediators in these two MC subclasses and explain in part their different functional properties. Rat peritoneal (PMC) and intestinal mast cells (IMC) were isolated and purified using a percoll gradient, and the efflux of 5-HT from each SG was measured by amperometric detection. IMC exhibited a ∼34% reduction in the release of 5-HT compared with PMC because of a lower number of exocytotic events, rather than a lower secretion per single exocytotic event. Amperometric spikes from IMC exhibited a slower decay phase and increased half-width but a similar ascending phase and foot parameters, indicating that the fusion pore kinetics are comparable in both MC subclasses. We conclude that both PG subtypes are equally efficient systems, directly involved in serotonin accumulation, and play a crucial role in regulating the kinetics of exocytosis from SG, providing specific secretory properties for the two cellular subtypes.

  5. Role of mast cells in fibrosis of classical Hodgkin lymphoma.

    PubMed

    Nakayama, Shoko; Yokote, Taiji; Hiraoka, Nobuya; Nishiwaki, Uta; Hanafusa, Toshiaki; Nishimura, Yasuichiro; Tsuji, Motomu

    2016-12-01

    The underlying mechanism of fibrosis in classical Hodgkin lymphoma (CHL) remains uncertain. This study aimed to investigate the association of fibrosis in the lymph nodes of patients with CHL through histological examination of the expression of cytokines associated with fibrosis and mast cell proliferation. Additionally, we sought to determine the degree of mast cell infiltration in a nodular sclerosis subtype of CHL (NSCHL) compared with that in non-NSCHL. We analyzed lymph nodes from 22 patients with CHL, of which eight were of the NSCHL and 14 of the non-NSCHL subtype, using immunohistochemical staining of forkhead box P3 (FOXP3), transforming growth factor (TGF)-β, interleukin (IL)-3, IL-13, and stem cell factor (SCF). Mast cells were positive for TGF-β and IL-13, and FOXP3-positive cells were negative for TGF-β. Only the expression of IL-13 in Hodgkin and Reed-Sternberg (HRS) cells was significantly more frequently observed in NSCHL than that in non-NSCHL (P = 0.0028) and was associated with a higher rate of fibrosis (P = 0.0097). The number of mast cells was significantly higher in NSCHL than that in non-NSCHL (P = 0.0001). A significantly positive correlation was observed between the rate of fibrosis and the number of mast cells (correlation coefficient, 0.8524; 95% CI, 0.6725-0.9372) (P <0.0001). The number of mast cells was significantly higher in the group with IL-13-positive HRS cells than that in the group with IL-13-negative HRS cells (P = 0.0157). Based on these findings, we hypothesize that IL-13 production by HRS cells may lead to fibrosis, and furthermore, promote mast cell proliferation and infiltration. This in turn might further produce the fibrotic cytokines IL-13 and TGF-β, resulting in fibrosis typical of NSCHL.

  6. Approaches for Analyzing the Roles of Mast Cells and Their Proteases In Vivo

    PubMed Central

    Galli, Stephen J.; Tsai, Mindy; Marichal, Thomas; Tchougounova, Elena; Reber, Laurent L.; Pejler, Gunnar

    2016-01-01

    The roles of mast cells in health and disease remain incompletely understood. While the evidence that mast cells are critical effector cells in IgE-dependent anaphylaxis and other acute IgE-mediated allergic reactions seems unassailable, studies employing various mice deficient in mast cells or mast cell-associated proteases have yielded divergent conclusions about the roles of mast cells or their proteases in certain other immunological responses. Such “controversial” results call into question the relative utility of various older versus newer approaches to ascertain the roles of mast cells and mast cell proteases in vivo. This review discusses how both older and more recent mouse models have been used to investigate the functions of mast cells and their proteases in health and disease. We particularly focus on settings in which divergent conclusions about the importance of mast cells and their proteases have been supported by studies that employed different models of mast cell or mast cell protease deficiency. We think that two major conclusions can be drawn from such findings: (1) no matter which models of mast cell or mast cell protease deficiency one employs, the conclusions drawn from the experiments always should take into account the potential limitations of the models (particularly abnormalities affecting cell types other than mast cells) and (2) even when analyzing a biological response using a single model of mast cell or mast cell protease deficiency, details of experimental design are critical in efforts to define those conditions under which important contributions of mast cells or their proteases can be identified. PMID:25727288

  7. Effects of ionizing radiation on differentiation of murine bone marrow cells into mast cells.

    PubMed

    Murakami, Sho; Yoshino, Hironori; Ishikawa, Junya; Yamaguchi, Masaru; Tsujiguchi, Takakiyo; Nishiyama, Ayaka; Yokoyama, Kouki; Kashiwakura, Ikuo

    2015-11-01

    Mast cells, immune effector cells produced from bone marrow cells, play a major role in immunoglobulin E-mediated allergic responses. Ionizing radiation affects the functions of mast cells, which are involved in radiation-induced tissue damage. However, whether ionizing radiation affects the differential induction of mast cells is unknown. Here we investigated whether bone marrow cells of X-irradiated mice differentiated into mast cells. To induce mast cells, bone marrow cells from X-irradiated and unirradiated mice were cultured in the presence of cytokines required for mast cell induction. Although irradiation at 0.5 Gy and 2 Gy decreased the number of bone marrow cells 1 day post-irradiation, the cultured bone marrow cells of X-irradiated and unirradiated mice both expressed mast cell-related cell-surface antigens. However, the percentage of mast cells in the irradiated group was lower than in the unirradiated group. Similar decreases in the percentage of mast cells induced in the presence of X-irradiation were observed 10 days post irradiation, although the number of bone marrow cells in irradiated mice had recovered by this time. Analysis of mast cell function showed that degranulation of mast cells after immunoglobulin E-mediated allergen recognition was significantly higher in the X-irradiated group compared with in the unirradiated group. In conclusion, bone marrow cells of X-irradiated mice differentiated into mast cells, but ionizing radiation affected the differentiation efficiency and function of mast cells.

  8. Imaging immune response of skin mast cells in vivo with two-photon microscopy

    NASA Astrophysics Data System (ADS)

    Li, Chunqiang; Pastila, Riikka K.; Lin, Charles P.

    2012-02-01

    Intravital multiphoton microscopy has provided insightful information of the dynamic process of immune cells in vivo. However, the use of exogenous labeling agents limits its applications. There is no method to perform functional imaging of mast cells, a population of innate tissue-resident immune cells. Mast cells are widely recognized as the effector cells in allergy. Recently their roles as immunoregulatory cells in certain innate and adaptive immune responses are being actively investigated. Here we report in vivo mouse skin mast cells imaging with two-photon microscopy using endogenous tryptophan as the fluorophore. We studied the following processes. 1) Mast cells degranulation, the first step in the mast cell activation process in which the granules are released into peripheral tissue to trigger downstream reactions. 2) Mast cell reconstitution, a procedure commonly used to study mast cells functioning by comparing the data from wild type mice, mast cell-deficient mice, and mast-cell deficient mice reconstituted with bone marrow-derived mast cells (BMMCs). Imaging the BMMCs engraftment in tissue reveals the mast cells development and the efficiency of BMMCs reconstitution. We observed the reconstitution process for 6 weeks in the ear skin of mast cell-deficient Kit wsh/ w-sh mice by two-photon imaging. Our finding is the first instance of imaging mast cells in vivo with endogenous contrast.

  9. Effects of seed abundance on seed scatter-hoarding of Edward's rat (Leopoldamys edwardsi Muridae) at the individual level.

    PubMed

    Zhang, Hongmao; Cheng, Jinrui; Xiao, Zhishu; Zhang, Zhibin

    2008-11-01

    Mast seeding is a common phenomenon, and has important effects on seed dispersal and hoarding by animals. At population level, the predator satiation hypothesis proposes that the satiating effect of a large amount of seeds on a relatively small number of predators benefits seed survival in mast-seeding years. However, the effect of mast seeding on the scatter-hoarding of rodents at the individual level is largely unknown. In this study, we investigated the effects of seed abundance (by simulating mast seeding and non-mast seeding) on the removal, consumption and scatter-hoarding of seeds of Camellia oleifera (Theaceae) by Edward's rat Leopoldamys edwardsi (Muridae) in seminatural enclosures in southwest China. We wanted to test the masting-enhanced hoarding hypothesis, which suggests that rodents tend to scatter-hoard more seeds in mast-seeding years in order to occupy more food resources. Our results indicate that L. edwardsi tended to disperse and scatter-hoard more seeds of C. oleifera per night with increasing seed abundance, and to eat less seeds per night when there was a high level of seed abundance in the enclosure experiments. These results support the masting-enhanced hoarding hypothesis. This capacity of rodents may be an evolutionary adaptation to the mast-seeding phenomenon. Our results suggest that mast seeding benefits forest regeneration not only through the predator satiation effect at the population level, but also through increased hoarding by animals at the individual level.

  10. The MAST motional Stark effect diagnostic.

    PubMed

    Conway, N J; De Bock, M F M; Michael, C A; Walsh, M J; Carolan, P G; Hawkes, N C; Rachlew, E; McCone, J F G; Shibaev, S; Wearing, G

    2010-10-01

    A motional Stark effect (MSE) diagnostic is now installed and operating routinely on the MAST spherical tokamak, with 35 radial channels, spatial resolution of ∼2.5 cm, and time resolution of ∼1 ms at angular noise levels of ∼0.5°. Conventional (albeit very narrow) interference filters isolate π or σ polarized emission. Avalanche photodiode detectors with digital phase-sensitive detection measure the harmonics of a pair of photoelastic modulators operating at 20 and 23 kHz, and thus the polarization state. The π component is observed to be significantly stronger than σ, in reasonably good agreement with atomic physics calculations, and as a result, almost all channels are now operated on π. Trials with a wide filter that admits the entire Stark pattern (relying on the net polarization of the emission) have demonstrated performance almost as good as the conventional channels. MSE-constrained equilibrium reconstructions can readily be produced between pulses.

  11. Mast cells mediate malignant pleural effusion formation

    PubMed Central

    Giannou, Anastasios D.; Marazioti, Antonia; Spella, Magda; Kanellakis, Nikolaos I.; Apostolopoulou, Hara; Psallidas, Ioannis; Prijovich, Zeljko M.; Vreka, Malamati; Zazara, Dimitra E.; Lilis, Ioannis; Papaleonidopoulos, Vassilios; Kairi, Chrysoula A.; Patmanidi, Alexandra L.; Giopanou, Ioanna; Spiropoulou, Nikolitsa; Harokopos, Vaggelis; Aidinis, Vassilis; Spyratos, Dionisios; Teliousi, Stamatia; Papadaki, Helen; Taraviras, Stavros; Snyder, Linda A.; Eickelberg, Oliver; Kardamakis, Dimitrios; Iwakura, Yoichiro; Feyerabend, Thorsten B.; Rodewald, Hans-Reimer; Kalomenidis, Ioannis; Blackwell, Timothy S.; Agalioti, Theodora; Stathopoulos, Georgios T.

    2015-01-01

    Mast cells (MCs) have been identified in various tumors; however, the role of these cells in tumorigenesis remains controversial. Here, we quantified MCs in human and murine malignant pleural effusions (MPEs) and evaluated the fate and function of these cells in MPE development. Evaluation of murine MPE-competent lung and colon adenocarcinomas revealed that these tumors actively attract and subsequently degranulate MCs in the pleural space by elaborating CCL2 and osteopontin. MCs were required for effusion development, as MPEs did not form in mice lacking MCs, and pleural infusion of MCs with MPE-incompetent cells promoted MPE formation. Once homed to the pleural space, MCs released tryptase AB1 and IL-1β, which in turn induced pleural vasculature leakiness and triggered NF-κB activation in pleural tumor cells, thereby fostering pleural fluid accumulation and tumor growth. Evaluation of human effusions revealed that MCs are elevated in MPEs compared with benign effusions. Moreover, MC abundance correlated with MPE formation in a human cancer cell–induced effusion model. Treatment of mice with the c-KIT inhibitor imatinib mesylate limited effusion precipitation by mouse and human adenocarcinoma cells. Together, the results of this study indicate that MCs are required for MPE formation and suggest that MC-dependent effusion formation is therapeutically addressable. PMID:25915587

  12. Secreted phospholipase A2 and mast cells.

    PubMed

    Murakami, Makoto; Taketomi, Yoshitaka

    2015-01-01

    Phospholipase A2s (PLA2s) are a group of enzymes that hydrolyze the sn-2 position of phospholipids to release (typically unsaturated) fatty acids and lysophospholipids, which serve as precursors for a variety of bioactive lipid mediators. Among the PLA2 superfamily, secreted PLA2 (sPLA2) enzymes comprise the largest subfamily that includes 11 isoforms with a conserved His-Asp catalytic dyad. Individual sPLA2 enzymes exhibit unique tissue and cellular localizations and specific enzymatic properties, suggesting their distinct biological roles. Recent studies using transgenic and knockout mice for individual sPLA2 isofoms have revealed their involvement in various pathophysiological events. Here, we overview the current state of knowledge about sPLA2s, specifically their roles in mast cells (MCs) in the context of allergology. In particular, we highlight group III sPLA2 (PLA2G3) as an "anaphylactic sPLA2" that promotes MC maturation and thereby anaphylaxis through a previously unrecognized lipid-orchestrated circuit.

  13. Eosinophils and mast cells in leishmaniasis

    PubMed Central

    Wilson, Mary E.

    2016-01-01

    Leishmania spp. are parasitic protozoa endemic in tropical and subtropical regions and the causative agent of leishmaniasis, a collection of syndromes whose clinical manifestations vary according to host and pathogen factors. Leishmania spp. are inoculated into the mammalian host by the bite of an infected sand fly, whereupon they are taken up by phagocytosis, convert into the replicative amastigote stage within macrophages, reproduce, spread to new macrophages and cause disease manifestations. A curative response against leishmaniasis depends in the classical activation of macrophages and the IL-12-dependent onset of an adaptive type 1 response characterized by the production of IFN-γ. Emerging evidence suggests that neutrophils, dendritic cells and other immune cells can serve as either temporary or stable hosts for Leishmania spp. Furthermore, it is becoming apparent that the initial interactions of the parasite with resident or early recruited immune cells can shape both the macrophage response and the type of adaptive immune response being induced. In this review, we compile a growing number of studies demonstrating how the earliest interactions of Leishmania spp. with eosinophils and mast cells influence the macrophage response to infection and the development of the adaptive immune response, hence, determining the ultimate outcome of infection. PMID:24838146

  14. Actin filament organization in activated mast cells is regulated by heterotrimeric and small GTP-binding proteins

    PubMed Central

    1994-01-01

    Rat peritoneal mast cells, both intact and permeabilized, have been used widely as model secretory cells. GTP-binding proteins and calcium play a major role in controlling their secretory response. Here we have examined changes in the organization of actin filaments in intact mast cells after activation by compound 48/80, and in permeabilized cells after direct activation of GTP-binding proteins by GTP-gamma-S. In both cases, a centripetal redistribution of cellular F-actin was observed: the content of F-actin was reduced in the cortical region and increased in the cell interior. The overall F-actin content was increased. Using permeabilized cells, we show that AIF4-, an activator of heterotrimeric G proteins, induces the disassembly of F-actin at the cortex, while the appearance of actin filaments in the interior of the cell is dependent on two small GTPases, rho and rac. Rho was found to be responsible for de novo actin polymerization, presumably from a membrane-bound monomeric pool, while rac was required for an entrapment of the released cortical filaments. Thus, a heterotrimeric G-protein and the small GTPases, rho and rac, participate in affecting the changes in the actin cytoskeleton observed after activation of mast cells. PMID:8051203

  15. Nucleoside 5′-O-monophosphorothioates as modulators of the P2Y14 receptor and mast cell degranulation

    PubMed Central

    Gendaszewska-Darmach, Edyta; Węgłowska, Edyta; Walczak-Drzewiecka, Aurelia; Karaś, Kaja

    2016-01-01

    Mast cells (MCs) are long-lived resident cells known for their substantial role in antigen-induced anaphylaxis and other immunoglobulin E-mediated allergic reactions as well as tumor promotion. MCs' activation results in the release of pro-inflammatory factors such as histamine, tryptase, tumor necrosis factor or carboxypeptidase A stored in secretory granules. IgE-dependent hypersensitivity has been thought to be the major pathway mediating degranulation of mast cells, but the P2Y14 nucleotide receptor activated by UDP-glucose (UDPG) may also enhance this process. In this study we identified thymidine 5'-O-monophosphorothioate (TMPS) as a molecule inhibiting UDPG-induced degranulation in a rat mast cell line (RBL-2H3). Additionally, TMPS diminished UDPG-evoked intracellular calcium mobilization in a stable HEK293T cell line overexpressing the P2Y14 receptor. Therefore, we demonstrate that the use of thymidine 5'-O-monophosphorothioate might be a novel anti-inflammatory approach based on preventingmast cell activation. PMID:27732965

  16. Sesamin attenuates mast cell-mediated allergic responses by suppressing the activation of p38 and nuclear factor-κB.

    PubMed

    Li, Liang Chang; Piao, Hong Mei; Zheng, Ming Yu; Lin, Zhen Hua; Li, Guangzhao; Yan, Guang Hai

    2016-01-01

    Establishing therapeutic agents for the treatment of allergic diseases is an important focus of human health research. Sesamin, a lignan in sesame oil, exhibits a diverse range of pharmacological properties. However, to the best of our knowledge, the effect of sesamin on mast cell‑mediated allergic responses has not yet been investigated. Thus, the aim of the present study was to investigate the effect of sesamin on mast cell‑mediated allergic responses and the underlying mechanisms by which it produces this effect. In rats, oral administration of sesamin inhibited passive cutaneous anaphylaxis. Sesamin exposure attenuated immunoglobulin E‑induced histamine release from rat peritoneal mast cells, which was indicated to be mediated by the modulation of intracellular calcium. In human mast cells, sesamin reduced the stimulatory effects of phorbol 12‑myristate 13‑acetate and calcium ionophore A23187 on the production and secretion of pro‑inflammatory cytokines, including tumor necrosis factor‑α and interleukin‑6. The inhibitory effect of sesamin on pro‑inflammatory cytokine production was dependent on nuclear factor κ‑light‑chain‑enhancer of activated B cells (NF‑κB) and p38 mitogen‑activated protein kinase (MAPK). The present study demonstrates that sesamin inhibits mast cell‑derived inflammatory allergic reactions by blocking histamine release, and pro‑inflammatory cytokine production and secretion. In addition, the findings indicate that the effect of sesamin is mediated by its effect on p38 MAPK/NF‑κB signaling. Furthermore, the in vivo and in vitro anti‑allergic effects of sesamin reported in the present study suggest that it is a promising therapeutic agent for the treatment of inflammatory allergic diseases.

  17. Analyzing the Functions of Mast Cells In Vivo Using 'Mast Cell Knock-in' Mice.

    PubMed

    Gaudenzio, Nicolas; Sibilano, Riccardo; Starkl, Philipp; Tsai, Mindy; Galli, Stephen J; Reber, Laurent L

    2015-05-27

    Mast cells (MCs) are hematopoietic cells which reside in various tissues, and are especially abundant at sites exposed to the external environment, such as skin, airways and gastrointestinal tract. Best known for their detrimental role in IgE-dependent allergic reactions, MCs have also emerged as important players in host defense against venom and invading bacteria and parasites. MC phenotype and function can be influenced by microenvironmental factors that may differ according to anatomic location and/or based on the type or stage of development of immune responses. For this reason, we and others have favored in vivo approaches over in vitro methods to gain insight into MC functions. Here, we describe methods for the generation of mouse bone marrow-derived cultured MCs (BMCMCs), their adoptive transfer into genetically MC-deficient mice, and the analysis of the numbers and distribution of adoptively transferred MCs at different anatomical sites. This method, named the 'mast cell knock-in' approach, has been extensively used over the past 30 years to assess the functions of MCs and MC-derived products in vivo. We discuss the advantages and limitations of this method, in light of alternative approaches that have been developed in recent years.

  18. Mercury induces inflammatory mediator release from human mast cells

    PubMed Central

    2010-01-01

    Background Mercury is known to be neurotoxic, but its effects on the immune system are less well known. Mast cells are involved in allergic reactions, but also in innate and acquired immunity, as well as in inflammation. Many patients with Autism Spectrum Disorders (ASD) have "allergic" symptoms; moreover, the prevalence of ASD in patients with mastocytosis, characterized by numerous hyperactive mast cells in most tissues, is 10-fold higher than the general population suggesting mast cell involvement. We, therefore, investigated the effect of mercuric chloride (HgCl2) on human mast cell activation. Methods Human leukemic cultured LAD2 mast cells and normal human umbilical cord blood-derived cultured mast cells (hCBMCs) were stimulated by HgCl2 (0.1-10 μM) for either 10 min for beta-hexosaminidase release or 24 hr for measuring vascular endothelial growth factor (VEGF) and IL-6 release by ELISA. Results HgCl2 induced a 2-fold increase in β-hexosaminidase release, and also significant VEGF release at 0.1 and 1 μM (311 ± 32 pg/106 cells and 443 ± 143 pg/106 cells, respectively) from LAD2 mast cells compared to control cells (227 ± 17 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to the proinflammatory neuropeptide substance P (SP, 0.1 μM) had synergestic action in inducing VEGF from LAD2 mast cells. HgCl2 also stimulated significant VEGF release (360 ± 100 pg/106 cells at 1 μM, n = 5, p < 0.05) from hCBMCs compared to control cells (182 ± 57 pg/106 cells), and IL-6 release (466 ± 57 pg/106 cells at 0.1 μM) compared to untreated cells (13 ± 25 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to SP (5 μM) further increased IL-6 release. Conclusions HgCl2 stimulates VEGF and IL-6 release from human mast cells. This phenomenon could disrupt the blood-brain-barrier and permit brain inflammation. As a result, the findings of the present study provide a biological mechanism for how low levels of mercury may contribute to ASD

  19. Antiallergic and antiasthmatic effects of a novel enhydrazinone ester (CEE-1): inhibition of activation of both mast cells and eosinophils.

    PubMed

    Ezeamuzie, Charles I; El-Hashim, Ahmed Z; Renno, Waleed M; Edafiogho, Ivan O

    2014-08-01

    Activation of mast cells and eosinophils is a fundamental process in the pathophysiology of allergic diseases. We have previously reported that the novel enhydrazinone ester CEE-1 (ethyl 4-phenylhydrazinocyclohex-3-en-2-oxo-6-phenyl-1-oate) possesses potent anti-inflammatory activity. We have now tested whether the compound also possesses antiallergic and antiasthmatic effects in vitro and in vivo. The compound significantly inhibited degranulation and leukotriene C4 (LTC4) release from activated human eosinophils, as well as IgE-dependent degranulation and LTC4 release from passively sensitized rat basophilic leukemia cells and bone marrow-derived mouse mast cells. In human eosinophils, the drug was more potent in inhibiting degranulation than LTC4 release {IC50 = 0.4 μM [confidence interval (CI): 0.1-0.9] versus 3.8 μM (CI: 0.9-8.3)}, whereas in mast cells the reverse was essentially the case. The drug did not affect stimulus-induced calcium transients in eosinophils but significantly inhibited early phosphorylation of extracellular signal-regulated kinases 1/2 and p38-mitogen-activated protein kinases (MAPK). In vivo, topical application of 4.5-15 mg/kg of the compound significantly inhibited allergen-induced passive cutaneous anaphylaxis in mice. Similarly, in the mouse asthma model, the intranasal administration of 6.5-12.5 mg/kg of the compound significantly inhibited bronchial inflammation and eosinophil accumulation in bronchial lavage fluid, as well as abolishing airway hyper-responsiveness to methacholine. These results show that CEE-1 inhibits the activation of both mast cells and eosinophils in vitro, probably by blocking MAPK-activation pathways, and that these effects are translated into antiallergic and antiasthmatic effects in vivo. The compound, therefore, has potential application in the treatment of asthma and other allergic diseases.

  20. Mast cell homeostasis and the JAK–STAT pathway

    PubMed Central

    Morales, JK; Falanga, YT; Depcrynski, A; Fernando, J; Ryan, JJ

    2011-01-01

    The Janus kinase/signal transducer and activator of transcription (JAK–STAT) pathway mediates important responses in immune cells. Activation of any of the four JAK family members leads to phosphorylation of one or more of seven STAT family members. Phosphorylation of STAT family members leads to their dimerization and translocation into the nucleus, in which they bind specific DNA sequences to activate gene transcription. Regulation of JAKs and STATs therefore has a significant effect on signal transduction and subsequent cellular responses. Mast cells are important mediators of allergic disease and asthma. These cells have the ability to cause profound inflammation and vasodilation upon the release of preformed mediators, as well as subsequent synthesis of new inflammatory mediators. The regulation of mast cells is therefore of intense interest for the treatment of allergic disease. An important regulator of mast cells, STAT5, is activated downstream of the receptors for immunoglobulin E, interleukin-3 and stem cell factor. STAT5 contributes to mast cell homeostasis, by mediating proliferation, survival, and mediator release. Regulators of the JAK–STAT pathway, such as the suppressors of cytokine signaling (SOCS) and protein inhibitor of activated STAT (PIAS) proteins, are required to fine tune the immune response and maintain homeostasis. A better understanding of the role and regulation of JAKs and STATs in mast cells is vital for the development of new therapeutics. PMID:20535135

  1. The Role of Mast Cells in Irritable Bowel Syndrome

    PubMed Central

    Lee, Oh Young

    2016-01-01

    Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, but its treatment is unsatisfactory as its pathophysiology is multifactorial. The putative factors of IBS pathophysiology are visceral hypersensitivity and intestinal dysmotility, also including psychological factors, dysregulated gut-brain axis, intestinal microbiota alterations, impaired intestinal permeability, and mucosal immune alterations. Recently, mucosal immune alterations have received much attention with the role of mast cells in IBS. Mast cells are abundant in the intestines and function as intestinal gatekeepers at the interface between the luminal environment in the intestine and the internal milieu under the intestinal epithelium. As a gatekeeper at the interface, mast cells communicate with the adjacent cells such as epithelial, neuronal, and other immune cells throughout the mediators released when they themselves are activated. Many studies have suggested that mast cells play a role in the pathophysiology of IBS. This review will focus on studies of the role of mast cell in IBS and the limitations of studies and will also consider future directions. PMID:28115927

  2. Mast Cells as Cellular Sensors in Inflammation and Immunity

    PubMed Central

    Beghdadi, Walid; Madjene, Lydia Célia; Benhamou, Marc; Charles, Nicolas; Gautier, Gregory; Launay, Pierre; Blank, Ulrich

    2011-01-01

    Mast cells are localized in tissues. Intense research on these cells over the years has demonstrated their role as effector cells in the maintenance of tissue integrity following injury produced by infectious agents, toxins, metabolic states, etc. After stimulation they release a sophisticated array of inflammatory mediators, cytokines, and growth factors to orchestrate an inflammatory response. These mediators can directly initiate tissue responses on resident cells, but they have also been shown to regulate other infiltrating immune cell functions. Research in recent years has revealed that the outcome of mast cell actions is not always detrimental for the host but can also limit disease development. In addition, mast cell functions highly depend on the physiological context in the organism. Depending on the genetic background, strength of the injurious event, the particular microenvironment, mast cells direct responses ranging from pro- to anti-inflammatory. It appears that they have evolved as cellular sensors to discern their environment in order to initiate an appropriate physiological response either aimed to favor inflammation for repair or at the contrary limit the inflammatory process to prevent further damage. Like every sophisticated machinery, its dysregulation leads to pathology. Given the broad distribution of mast cells in tissues this also explains their implication in many inflammatory diseases. PMID:22566827

  3. Mast cell sarcoma: new cases and literature review

    PubMed Central

    Canioni, Danielle; Lhermitte, Ludovic; Soussan, Michael; Arock, Michel; Bruneau, Julie; Dubreuil, Patrice; Bodemer, Christine; Chandesris, Marie-Olivia; Lortholary, Olivier; Hermine, Olivier; Damaj, Gandhi

    2016-01-01

    Mast cell sarcoma (MCS) is a rare form of mastocytosis characterized by the presence of solid tumor(s) comprising malignant mast cells that harbor destructive infiltration capability and metastatic potential. Here, we present an extensive literature review and report on 23 cases of MCS, including 3 new cases from the French National Reference Center for Mastocytosis. From our analysis, it appears that MCS can occur at any age. It can manifest de novo or, to a lesser extent, may evolve from a previously established mastocytosis. Bone tumor is a frequent manifestation, and symptoms of mast cell activation are rare. Histological diagnosis can be difficult because MCS is frequently composed of highly atypical neoplastic mast cells and can thus mimic other tumors. Unexpectedly, the canonical KIT D816V mutation is found in only 21% of MCS; therefore, complete KIT gene sequencing is required. The prognosis of patients with MCS is poor, with a median survival time of less than 18 months, and progression to mast cell leukemia is not unusual. Because conventional chemotherapies usually fail, the role of targeted therapies and bone marrow transplantation warrants further investigation in such aggressive neoplasms. PMID:27602777

  4. Mast cell and histamine content of human bronchoalveolar lavage fluid.

    PubMed Central

    Agius, R M; Godfrey, R C; Holgate, S T

    1985-01-01

    Bronchoalveolar lavage was performed in 97 patients including control patients with bronchial carcinoma (24) and patients with sarcoidosis (20), cryptogenic fibrosing alveolitis (9), and asthma (4), and others. Cytocentrifuged slides were stained by two methods: May-Grünwald Giemsa and toluidine blue. In the last 32 subjects the bronchoalveolar lavage fluid was separated into supernatant and cell pellet for the subsequent assay of the performed mast cell mediator, histamine. Comparison of the two methods of staining showed a bias towards toluidine blue. Controls had a differential mean (SE) mast cell count of 0.07% (0.01%). Higher counts were noted in cryptogenic fibrosing alveolitis--0.61% (0.15%) (p less than 0.001)--and in sarcoidosis--0.14% (0.02%) (p less than 0.05). There was a strong correlation between absolute mast cell counts and cell lysate histamine concentration (r = 0.78, p less than 0.001). Less strong, significant, correlations between supernatant histamine concentration and absolute mast cell counts (r = 0.48, p less than 0.01) or cell lysate histamine concentration (r = 0.72, p less than 0.01) were also found. Derived mean values of histamine per mast cell ranged from 3.7 to 10.9 picograms. The mean histamine content of lavage fluid supernatant as a percentage of the total lavage fluid histamine was 24.9% (3.3%). The possible clinical significance of these findings is discussed. Images PMID:4060097

  5. Mast cell heterogeneity in non-human primates

    SciTech Connect

    Barrett, K.E.; Szucs, E.F.; Metcalfe, D.D.

    1986-03-05

    Mast cells of rodents may be subdivided in terms of their properties, but the extent of such heterogeneity in man and higher animals is still unknown. The authors have compared lung (LMC) and intestinal (IMC) mast cells obtained from individual monkeys. LMC contained more histamine (HA) than IMC (6.61+/-1.3 vs. 1.6+/-0.6 pg/cell, means+/-SEM, n=3). LMC released more HA (17.7+/-2.1% vs. 9.2+/-1.0%, means+/-SEM, n=16) and also generated more LTC/sub 4/ equivalents as measured by radioimmunoassay (range 13.4-41.5 vs. 3.0-4.0 ng/10/sup 6/ mast cells) following an anaphylactic stimulus. The majority (>90%) of LMC stained metachromatically under conditions appropriate for heparin-containing cells, whereas IMC required more forcing conditions to display metachromasia. In contrast to these quantitative and qualitative mediator differences, functional responses of LMC and IMC were similar. Thus, HA release was inhibited comparably by theophylline, isoprenaline and dibutyryl cyclic AMP, but quercetin was slightly more active on IMC. Substance P caused dose-related HA release from both cell types, although the amount released varied between individual animal, (range LMC 1.2-20.2%, IMC 1.8-23.0%, n=4). Other neuropeptides (pentagastrin) vasoactive intestinal peptide, neurotensin, somatostatin) did not release HA. They conclude that mast cell heterogeneity in higher animals may be reflected more by cytochemical rather than functional differences between mast cell classes.

  6. Expression profiling of constitutive mast cells reveals a unique identity within the immune system

    PubMed Central

    Dwyer, Daniel F.; Barrett, Nora A.; Austen, K. Frank

    2016-01-01

    Mast cells are evolutionarily ancient sentinel cells. Like basophils, mast cells express the high-affinity IgE receptor and are implicated in host defense and diverse immune-mediated diseases. To better characterize the function of these cells, we assessed the transcriptional profiles of mast cells isolated from peripheral connective tissues and basophils isolated from spleen and blood. We found that mast cells were transcriptionally distinct, clustering independently from all other profiled cells, and that mast cells demonstrated considerably greater heterogeneity across tissues than previously appreciated. We observed minimal homology between mast cells and basophils, which share more overlap with other circulating granulocytes than with mast cells. Derivation of mast cell and basophil transcriptional signatures underscores their differential capacity to detect environmental signals and influence the inflammatory milieu. PMID:27135604

  7. Mast cell tumour in a giant Galapagos tortoise (Geochelone nigra vicina).

    PubMed

    Santoro, M; Stacy, B A; Morales, J A; Gastezzi-Arias, P; Landazuli, S; Jacobson, E R

    2008-01-01

    A well-differentiated cutaneous mast cell tumour was diagnosed in a subadult female giant Galapagos tortoise. The tumour was a pedunculated, verrucose mass located near the base of the neck. The histological features, which were diagnostic for a mast cell tumour, included abundant intracytoplasmic granules that were stained metachromatically with Giemsa and toluidine blue stains. Mast cell tumours are rare in reptiles, and this is the first description of a mast cell tumour in a chelonian.

  8. Preliminary study on an innovative, simple mast cell-based electrochemical method for detecting foodborne pathogenic bacterial quorum signaling molecules (N-acyl-homoserine-lactones).

    PubMed

    Jiang, Donglei; Feng, Dongdong; Jiang, Hui; Yuan, Limin; Yongqi, Yin; Xu, Xin; Fang, Weiming

    2017-04-15

    This paper reports the a novel and simple mast cell-based electrochemical method for detecting of bacterial quorum signaling molecules, N-acylhomoserine lactones (AHLs), which can be utilized to preliminarily evaluate the toxicity of food-borne pathogenic bacteria. Rat basophilic leukemia (RBL-2H3) mast cells encapsulated in alginate/graphene oxide hydrogel were immobilized on a gold electrode, while mast cells as recognition elements were cultured in a 3D cell culture system. Electrochemical impedance spectroscopy (EIS) was utilized to record the cell impedance signal as-influenced by Pseudomonas aeruginosa quorum-sensing molecule, N-3-oxododecanoyl homoserine lactone (3OC12-HSL). The results indicated that cellular activities such as cell viability, apoptosis, intracellular calcium, and degranulation were markedly influenced by the AHLs. Importantly, the exposure of 3OC12-HSL to mast cells induced a marked decrease in the electrochemical impedance signal in a dose-dependent manner. The detection limit for 3OC12-HSL was 0.034μM with a linear range of 0.1-1μM. These results were confirmed via conventional cell assay and transmission electron microscope (TEM) analysis. Altogether, the proposed method appears to be an innovative and effective approach to the quantitative measurement of Gram-negative bacterial quorum signaling molecules; to this effect, it also may serve as a primary evaluation of the cytotoxicity of food-borne pathogens.

  9. Down-regulation of Heat Shock Protein HSP90ab1 in Radiation-damaged Lung Cells other than Mast Cells

    PubMed Central

    Geyer, Peter; Fitze, Guido; Baretton, Gustavo B.

    2014-01-01

    Ionizing radiation (IR) leads to fibrosing alveolitis (FA) after a lag period of several weeks to months. In a rat model, FA starts at 8 weeks after IR. Before that, at 5.5 weeks after IR, the transcription factors Sp1 (stimulating protein 1) and AP-1 (activator protein 1) are inactivated. To find genes/proteins that were down-regulated at that time, differentially expressed genes were identified in a subtractive cDNA library and verified by quantitative RT-PCR (reverse transcriptase polymerase chain reaction), western blotting and immunohistochemistry (IH). The mRNA of the molecular chaperone HSP90AB1 (heat shock protein 90 kDa alpha, class B member 1) was down-regulated 5.5 weeks after IR. Later, when FA manifested, HSP90ab1 protein was down-regulated by more than 90% in lung cells with the exception of mast cells. In most mast cells of the normal lung, both HSP90ab1 and HSP70, another major HSP, show a very low level of expression. HSP70 was massively up-regulated in all mast cells three months after irradiation whereas HSP90AB1 was up-regulated only in a portion of mast cells. The strong changes in the expression of central molecular chaperones may contribute to the well-known disturbance of cellular functions in radiation-damaged lung tissue. PMID:24670792

  10. Capillary electrophoretic study of individual exocytotic events in single mast cells

    SciTech Connect

    Ho, Andrea Ming-Wei

    1999-02-12

    The peak profile of individual degranulation events from the on-column release of serotonin from single rat peritoneal mast cells (RPMCs) was monitored using capillary electrophoresis with laser-induced native fluorescence detection (CE-LINF). Serotonin, an important biogenic amine, is contained in granules (0.25 fL) within RPMCs and is extruded by a process termed exocytosis. The secretagogue, Polymyxin B sulfate, was used as the CE running buffer after injection of a single RPMC into the separation capillary to stimulate the release of the granules. Because the release process occurs on a ms time scale, monitoring individual exocytotic events is possible with the coupling of high-speed CE and LINF detection.

  11. The role of mast cell in tissue morphogenesis. Thymus, duodenum, and mammary gland as examples.

    PubMed

    Ribatti, Domenico; Crivellato, Enrico

    2016-02-01

    Mast cells (MCs) are strategically located at host/environment interfaces like skin, airways, and gastro-intestinal and uro-genital tracts. MCs also populate connective tissues in association with blood and lymphatic vessels and nerves. MCs are absent in avascular tissues, such as mineralized bone, cartilage, and cornea. MCs have various functions and different functional subsets of MCs are encountered in different tissues. However, we do not' know exactly what is the physiological function of MC. Most of these functions are not essential for life, as various MC-deficient strains of mice and rats seems to have normal life spans. In this review article, we have reported and discussed the literature data concerning the role of MCs in tissue morphogenesis, and in particular their role in the development of thymus, duodenum, and mammary gland.

  12. The role of mast cells in neuroinflammation.

    PubMed

    Nelissen, Sofie; Lemmens, Evi; Geurts, Nathalie; Kramer, Peter; Maurer, Marcus; Hendriks, Jerome; Hendrix, Sven

    2013-05-01

    Mast cells (MCs) are densely granulated perivascular resident cells of hematopoietic origin and well known for their pathogenetic role in allergic and anaphylactic reactions. In addition, they are also involved in processes of innate and adaptive immunity. MCs can be activated in response to a wide range of stimuli, resulting in the release of not only pro-inflammatory, but also anti-inflammatory mediators. The patterns of secreted mediators depend upon the given stimuli and microenvironmental conditions, accordingly MCs have the ability to promote or attenuate inflammatory processes. Their presence in the central nervous system (CNS) has been recognized for more than a century. Since then a participation of MCs in various pathological processes in the CNS has been well documented. They can aggravate CNS damage in models of brain ischemia and hemorrhage, namely through increased blood-brain barrier damage, brain edema and hemorrhage formation and promotion of inflammatory responses to such events. In contrast, recent evidence suggests that MCs may have a protective role following traumatic brain injury by degrading pro-inflammatory cytokines via specific proteases. In neuroinflammatory diseases such as multiple sclerosis, the role of MCs seems to be ambiguous. MCs have been shown to be damaging, neuroprotective, or even dispensable, depending on the experimental protocols used. The role of MCs in the formation and progression of CNS tumors such as gliomas is complex and both positive and negative relationships between MC activity and tumor progression have been reported. In summary, MCs and their secreted mediators modulate inflammatory processes in multiple CNS pathologies and can thereby either contribute to neurological damage or confer neuroprotection. This review intends to give a concise overview of the regulatory roles of MCs in brain disease.

  13. Principles of treatment for mast cell tumors.

    PubMed

    Govier, Susanne M

    2003-05-01

    Mast cell tumors (MCT) are the most common malignant cutaneous tumors that occur in dogs. They are most commonly found on the trunk, accounting for approximately 50% to 60% of all sites. MCTs associated with the limbs account for approximately 25% of all sites. Cutaneous MCTs have a wide variety of clinical appearances. Histologic grade is the most consistent prognostic factor available for dogs. MCTs located at 'nail bed' (subungual), inguinal/preputial area, and any mucocutaneous area like perineum or oral cavity carry a guarded prognosis and tend to metastasize. MCTs usually exfoliate well and are cytologically distinct. The extent of staging procedures following fine-needle aspirate cytologic diagnosis is based on the presence or absence of negative prognostic indicators. Surgery is the treatment of choice for solitary MCTs with no evidence of metastasis. Reponses rates to chemotherapy, (partial response) as high as 78% have been reported, and preliminary evidence suggests that multiagent (prednisone and vinblastine) protocols may confer a higher response rate than single-agent therapy. MCTs are the second most common cutaneous tumor in the cat. There are two distinct forms of cutaneous MCTs in the cat. The more common form is the mastocytic form, and the less common is the histiocytic form. Unlike in the dog, the head and neck are the most common sites for MCTs in the cat followed by the trunk and limbs. Cats with disseminated forms of MCT often present with systemic signs of illness, which include depression, anorexia, weight loss, and vomiting. The diagnosis and staging of MCTs in cats is similar to that in the dog. As with dogs with cutaneous MCTs, surgery is the treatment of choice. Little is known about the effectiveness of adjunctive chemotherapy options for cutaneous MCTs. Adjunctive chemotherapy does not appear to increase survival times.

  14. Hemorrhage Exacerbates Radiation Effects on Survival, Leukocytopenia, Thrombopenia, Erythropenia, Bone Marrow Cell Depletion and Hematopoiesis, and Inflammation-Associated microRNAs Expression in Kidney

    PubMed Central

    Kiang, Juliann G.; Smith, Joan T.; Anderson, Marsha N.; Swift, Joshua M.; Christensen, Christine L.; Gupta, Paridhi; Balakathiresan, Nagaraja; Maheshwari, Radha K.

    2015-01-01

    Exposure to high-dose radiation results in detrimental effects on survival. The effects of combined trauma, such as radiation in combination with hemorrhage, the typical injury of victims exposed to a radiation blast, on survival and hematopoietic effects have yet to be understood. The purpose of this study was to evaluate the effects of radiation injury (RI) combined with hemorrhage (i.e., combined injury, CI) on survival and hematopoietic effects, and to investigate whether hemorrhage (Hemo) enhanced RI-induced mortality and hematopoietic syndrome. Male CD2F1 mice (10 weeks old) were given one single exposure of γ- radiation (60Co) at various doses (0.6 Gy/min). Within 2 hr after RI, animals under anesthesia were bled 0% (Sham) or 20% (Hemo) of total blood volume via the submandibular vein. In these mice, Hemo reduced the LD50/30 for 30-day survival from 9.1 Gy (RI) to 8.75 Gy (CI) with a DMF of 1.046. RI resulted in leukocytopenia, thrombopenia, erythropenia, and bone marrow cell depletion, but decreased the caspase-3 activation response. RI increased IL-1β, IL-6, IL-17A, and TNF-α concentrations in serum, bone marrow, ileum, spleen, and kidney. Some of these adverse alterations were magnified by CI. Erythropoietin production was increased in kidney and blood more after CI than RI. Furthermore, CI altered the global miRNAs expression in kidney and the ingenuity pathway analysis showed that miRNAs viz., let-7e, miR-30e and miR-29b that were associated with hematopoiesis and inflammation. This study provides preliminary evidence that non-lethal Hemo exacerbates RI-induced mortality and cell losses associated with high-dose γ-radiation. We identified some of the initial changes occurring due to CI which may have facilitated in worsening the injury and hampering the recovery of animals ultimately resulting in higher mortality. PMID:26422254

  15. The effect of red blood cell aggregation on velocity and cell-depleted layer characteristics of blood in a bifurcating microchannel

    PubMed Central

    Sherwood, J. M.; Dusting, J.; Kaliviotis, E.; Balabani, S.

    2012-01-01

    Red blood cell (RBC) aggregation is a multifaceted phenomenon, and whether it is generally beneficial or deleterious remains unclear. In order to better understand its effect on microvascular blood flow, the phenomenon must be studied in complex geometries, as it is strongly dependent on time, flow, and geometry. The cell-depleted layer (CDL) which forms at the walls of microvessels has been observed to be enhanced by aggregation; however, details of the characteristics of the CDL in complex regions, such as bifurcations, require further investigation. In the present study, a microchannel with a T-junction was used to analyze the influence of aggregation on the flow field and the CDL. Micro-PIV using RBCs as tracers provided high resolution cell velocity data. CDL characteristics were measured from the same data using a newly developed technique based on motion detection. Skewed and sharpened velocity profiles in the daughter branches were observed, contrary to the behavior of a continuous Newtonian fluid. RBC aggregation was observed to increase the skewness, but decrease the sharpening, of the velocity profiles in the daughter branches. The CDL width was found to be significantly greater, with a wider distribution, in the presence of aggregation and the mean width increased proportionally with the reciprocal of the fraction of flow entering the daughter branch. Aggregation also significantly increased the roughness of the interface between the CDL and the RBC core. The present results provide further insight into how RBC aggregation may affect the flow in complex geometries, which is of importance in both understanding its functions invivo, and utilizing it as a tool in microfluidic devices. PMID:23667411

  16. Hemorrhage Exacerbates Radiation Effects on Survival, Leukocytopenia, Thrombopenia, Erythropenia, Bone Marrow Cell Depletion and Hematopoiesis, and Inflammation-Associated microRNAs Expression in Kidney.

    PubMed

    Kiang, Juliann G; Smith, Joan T; Anderson, Marsha N; Swift, Joshua M; Christensen, Christine L; Gupta, Paridhi; Balakathiresan, Nagaraja; Maheshwari, Radha K

    2015-01-01

    Exposure to high-dose radiation results in detrimental effects on survival. The effects of combined trauma, such as radiation in combination with hemorrhage, the typical injury of victims exposed to a radiation blast, on survival and hematopoietic effects have yet to be understood. The purpose of this study was to evaluate the effects of radiation injury (RI) combined with hemorrhage (i.e., combined injury, CI) on survival and hematopoietic effects, and to investigate whether hemorrhage (Hemo) enhanced RI-induced mortality and hematopoietic syndrome. Male CD2F1 mice (10 weeks old) were given one single exposure of γ- radiation (60Co) at various doses (0.6 Gy/min). Within 2 hr after RI, animals under anesthesia were bled 0% (Sham) or 20% (Hemo) of total blood volume via the submandibular vein. In these mice, Hemo reduced the LD50/30 for 30-day survival from 9.1 Gy (RI) to 8.75 Gy (CI) with a DMF of 1.046. RI resulted in leukocytopenia, thrombopenia, erythropenia, and bone marrow cell depletion, but decreased the caspase-3 activation response. RI increased IL-1β, IL-6, IL-17A, and TNF-α concentrations in serum, bone marrow, ileum, spleen, and kidney. Some of these adverse alterations were magnified by CI. Erythropoietin production was increased in kidney and blood more after CI than RI. Furthermore, CI altered the global miRNAs expression in kidney and the ingenuity pathway analysis showed that miRNAs viz., let-7e, miR-30e and miR-29b that were associated with hematopoiesis and inflammation. This study provides preliminary evidence that non-lethal Hemo exacerbates RI-induced mortality and cell losses associated with high-dose γ-radiation. We identified some of the initial changes occurring due to CI which may have facilitated in worsening the injury and hampering the recovery of animals ultimately resulting in higher mortality.

  17. NNKTT120, an anti-iNKT cell monoclonal antibody, produces rapid and sustained iNKT cell depletion in adults with sickle cell disease

    PubMed Central

    Majerus, Elaine; Ataga, Kenneth I.; Vichinsky, Elliot P.; Schaub, Robert; Mashal, Robert; Nathan, David G.

    2017-01-01

    Invariant NKT (iNKT) cells can be activated to stimulate a broad inflammatory response. In murine models of sickle cell disease (SCD), interruption of iNKT cell activity prevents tissue injury from vaso-occlusion. NKTT120 is an anti-iNKT cell monoclonal antibody that has the potential to rapidly and specifically deplete iNKT cells and, potentially, prevent vaso-occlusion. We conducted an open-label, multi-center, single-ascending-dose study of NKTT120 to determine its pharmacokinetics, pharmacodynamics and safety in steady-state patients with SCD. Doses were escalated in a 3+3 study design over a range from 0.001 mg/kg to 1.0 mg/kg. Twenty-one adults with SCD were administered NKTT120 as part of 7 dose cohorts. Plasma levels of NKTT120 predictably increased with higher doses. Median half-life of NKTT120 was 263 hours. All subjects in the higher dose cohorts (0.1 mg/kg, 0.3 mg/kg, and 1 mg/kg) demonstrated decreased iNKT cells below the lower limit of quantification within 6 hours after infusion, the earliest time point at which they were measured. In those subjects who received the two highest doses of NKTT120 (0.3, 1 mg/kg), iNKT cells were not detectable in the peripheral blood for a range of 2 to 5 months. There were no serious adverse events in the study deemed to be related to NKTT120. In adults with SCD, NKTT120 produced rapid, specific and sustained iNKT cell depletion without any infusional toxicity or attributed serious adverse events. The next step is a trial to determine NKTT120’s ability to decrease rate of vaso-occlusive pain episodes. Trial Registration: clinicaltrials.gov NCT01783691. PMID:28152086

  18. The effect of red blood cell aggregation on velocity and cell-depleted layer characteristics of blood in a bifurcating microchannel.

    PubMed

    Sherwood, J M; Dusting, J; Kaliviotis, E; Balabani, S

    2012-06-01

    Red blood cell (RBC) aggregation is a multifaceted phenomenon, and whether it is generally beneficial or deleterious remains unclear. In order to better understand its effect on microvascular blood flow, the phenomenon must be studied in complex geometries, as it is strongly dependent on time, flow, and geometry. The cell-depleted layer (CDL) which forms at the walls of microvessels has been observed to be enhanced by aggregation; however, details of the characteristics of the CDL in complex regions, such as bifurcations, require further investigation. In the present study, a microchannel with a T-junction was used to analyze the influence of aggregation on the flow field and the CDL. Micro-PIV using RBCs as tracers provided high resolution cell velocity data. CDL characteristics were measured from the same data using a newly developed technique based on motion detection. Skewed and sharpened velocity profiles in the daughter branches were observed, contrary to the behavior of a continuous Newtonian fluid. RBC aggregation was observed to increase the skewness, but decrease the sharpening, of the velocity profiles in the daughter branches. The CDL width was found to be significantly greater, with a wider distribution, in the presence of aggregation and the mean width increased proportionally with the reciprocal of the fraction of flow entering the daughter branch. Aggregation also significantly increased the roughness of the interface between the CDL and the RBC core. The present results provide further insight into how RBC aggregation may affect the flow in complex geometries, which is of importance in both understanding its functions invivo, and utilizing it as a tool in microfluidic devices.

  19. Acute GVHD in patients receiving IL-15/4-1BBL activated NK cells following T-cell-depleted stem cell transplantation.

    PubMed

    Shah, Nirali N; Baird, Kristin; Delbrook, Cynthia P; Fleisher, Thomas A; Kohler, Mark E; Rampertaap, Shakuntala; Lemberg, Kimberly; Hurley, Carolyn K; Kleiner, David E; Merchant, Melinda S; Pittaluga, Stefania; Sabatino, Marianna; Stroncek, David F; Wayne, Alan S; Zhang, Hua; Fry, Terry J; Mackall, Crystal L

    2015-01-29

    Natural killer (NK) cells can enhance engraftment and mediate graft-versus-leukemia following allogeneic hematopoietic stem cell transplantation (HSCT), but the potency of graft-versus-leukemia mediated by naturally reconstituting NK cells following HSCT is limited. Preclinical studies demonstrate that activation of NK cells using interleukin-15 (IL-15) plus 4-1BBL upregulates activating receptor expression and augments killing capacity. In an effort to amplify the beneficial effects of NK cells post-HSCT, we conducted a first-in-human trial of adoptive transfer of donor-derived IL-15/4-1BBL-activated NK cells (aNK-DLI) following HLA-matched, T-cell-depleted (1-2 × 10(4) T cells/kg) nonmyeloablative peripheral blood stem cell transplantation in children and young adults with ultra-high-risk solid tumors. aNK-DLI were CD3(+)-depleted, CD56(+)-selected lymphocytes, cultured for 9 to 11 days with recombinant human IL-15 plus 4-1BBL(+)IL-15Rα(+) artificial antigen-presenting cells. aNK-DLI demonstrated potent killing capacity and displayed high levels of activating receptor expression. Five of 9 transplant recipients experienced acute graft-versus-host disease (GVHD) following aNK-DLI, with grade 4 GVHD observed in 3 subjects. GVHD was more common in matched unrelated donor vs matched sibling donor recipients and was associated with higher donor CD3 chimerism. Given that the T-cell dose was below the threshold required for GVHD in this setting, we conclude that aNK-DLI contributed to the acute GVHD observed, likely by augmenting underlying T-cell alloreactivity. This trial was registered at www.clinicaltrials.gov as #NCT01287104.

  20. 30 CFR 56.7051 - Loose objects on the mast or drill platform.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Loose objects on the mast or drill platform. 56... Drilling and Rotary Jet Piercing Drilling § 56.7051 Loose objects on the mast or drill platform. To prevent injury to personnel, tools and other objects shall not be left loose on the mast or drill platform....

  1. 30 CFR 56.7051 - Loose objects on the mast or drill platform.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Loose objects on the mast or drill platform. 56... Drilling and Rotary Jet Piercing Drilling § 56.7051 Loose objects on the mast or drill platform. To prevent injury to personnel, tools and other objects shall not be left loose on the mast or drill platform....

  2. Mast cells are required for phototolerance induction and scratching abatement.

    PubMed

    Schweintzger, Nina A; Bambach, Isabella; Reginato, Eleonora; Mayer, Gerlinde; Limón-Flores, Alberto Y; Ullrich, Stephen E; Byrne, Scott N; Wolf, Peter

    2015-07-01

    Dermal mast cells protect the skin from inflammatory effects of ultraviolet (UV) radiation and are required for UV-induced immune suppression. We sought to determine a potential mechanistic role of mast cells in reducing the sensitivity to UV radiation (i.e. phototolerance induction) through photohardening. We administered single UV exposures as well as a chronic UV irradiation regime to mast cell-deficient Kit(W-Sh/W-Sh) mice and their controls. The chronic irradiation protocol was similar to that given for prophylaxis in certain photodermatoses in humans. Compared to controls, UV-exposed Kit(W-Sh/W-Sh) mice were more susceptible to epidermal hyperplasia and dermal oedema which was linked to blood vessel dilation. Unexpectedly, Kit(W-Sh/W-Sh) mice exhibited an excessive scratching behaviour following broadband UVB plus UVA or solar simulated UV irradiation at doses far below their minimal skin-swelling dose. Protection from this UV-induced scratching phenotype was dependent on mast cells, as engraftment of bone marrow-derived cultured mast cells abated it entirely. Kit(W-Sh/W-Sh) mice were entirely resistant to phototolerance induction by photohardening treatment. Compared to controls, these mice also showed reduced numbers of regulatory T cells and neutrophils in the skin 24 h after UV irradiation. While it is well known that mast cell-deficient mice are resistant to UV-induced immune suppression, we have discovered that they are prone to develop photo-itch and are more susceptible to UV-induced epidermal hyperplasia and skin oedema.

  3. Mast cells, glia and neuroinflammation: partners in crime?

    PubMed

    Skaper, Stephen D; Facci, Laura; Giusti, Pietro

    2014-03-01

    Glia and microglia in particular elaborate pro-inflammatory molecules that play key roles in central nervous system (CNS) disorders from neuropathic pain and epilepsy to neurodegenerative diseases. Microglia respond also to pro-inflammatory signals released from other non-neuronal cells, mainly those of immune origin such as mast cells. The latter are found in most tissues, are CNS resident, and traverse the blood-spinal cord and blood-brain barriers when barrier compromise results from CNS pathology. Growing evidence of mast cell-glia communication opens new perspectives for the development of therapies targeting neuroinflammation by differentially modulating activation of non-neuronal cells that normally control neuronal sensitization - both peripherally and centrally. Mast cells and glia possess endogenous homeostatic mechanisms/molecules that can be up-regulated as a result of tissue damage or stimulation of inflammatory responses. Such molecules include the N-acylethanolamine family. One such member, N-palmitoylethanolamine is proposed to have a key role in maintenance of cellular homeostasis in the face of external stressors provoking, for example, inflammation. N-Palmitoylethanolamine has proven efficacious in mast-cell-mediated experimental models of acute and neurogenic inflammation. This review will provide an overview of recent progress relating to the pathobiology of neuroinflammation, the role of microglia, neuroimmune interactions involving mast cells and the possibility that mast cell-microglia cross-talk contributes to the exacerbation of acute symptoms of chronic neurodegenerative disease and accelerates disease progression, as well as promoting pain transmission pathways. We will conclude by considering the therapeutic potential of treating systemic inflammation or blockade of signalling pathways from the periphery to the brain in such settings.

  4. Mast cells, glia and neuroinflammation: partners in crime?

    PubMed Central

    Skaper, Stephen D; Facci, Laura; Giusti, Pietro

    2014-01-01

    Glia and microglia in particular elaborate pro-inflammatory molecules that play key roles in central nervous system (CNS) disorders from neuropathic pain and epilepsy to neurodegenerative diseases. Microglia respond also to pro-inflammatory signals released from other non-neuronal cells, mainly those of immune origin such as mast cells. The latter are found in most tissues, are CNS resident, and traverse the blood–spinal cord and blood–brain barriers when barrier compromise results from CNS pathology. Growing evidence of mast cell–glia communication opens new perspectives for the development of therapies targeting neuroinflammation by differentially modulating activation of non-neuronal cells that normally control neuronal sensitization – both peripherally and centrally. Mast cells and glia possess endogenous homeostatic mechanisms/molecules that can be up-regulated as a result of tissue damage or stimulation of inflammatory responses. Such molecules include the N-acylethanolamine family. One such member, N-palmitoylethanolamine is proposed to have a key role in maintenance of cellular homeostasis in the face of external stressors provoking, for example, inflammation. N-Palmitoylethanolamine has proven efficacious in mast-cell-mediated experimental models of acute and neurogenic inflammation. This review will provide an overview of recent progress relating to the pathobiology of neuroinflammation, the role of microglia, neuroimmune interactions involving mast cells and the possibility that mast cell–microglia cross-talk contributes to the exacerbation of acute symptoms of chronic neurodegenerative disease and accelerates disease progression, as well as promoting pain transmission pathways. We will conclude by considering the therapeutic potential of treating systemic inflammation or blockade of signalling pathways from the periphery to the brain in such settings. PMID:24032675

  5. Estrogen inhibits mast cell chymase release to prevent pressure overload-induced adverse cardiac remodeling.

    PubMed

    Li, Jianping; Jubair, Shaiban; Janicki, Joseph S

    2015-02-01

    Estrogen regulation of myocardial chymase and chymase effects on cardiac remodeling are unknown. To test the hypothesis that estrogen prevents pressure overload-induced adverse cardiac remodeling by inhibiting mast cell (MC) chymase release, transverse aortic constriction or sham surgery was performed in 7-week-old intact and ovariectomized (OVX) rats. Three days before creating the constriction, additional groups of OVX rats began receiving 17β-estradiol, a chymase inhibitor, or a MC stabilizer. Left ventricular function, cardiomyocyte size, collagen volume fraction, MC density and degranulation, and myocardial and plasma chymase levels were assessed 18 days postsurgery. Aortic constriction resulted in ventricular hypertrophy in intact and OVX groups, whereas collagen volume fraction was increased only in OVX rats. Chymase protein content was increased by aortic constriction in the intact and OVX groups, with the magnitude of the increase being greater in OVX rats. MC density and degranulation, plasma chymase levels, and myocardial active transforming growth factor-β1 levels were increased by aortic constriction only in OVX rats. Estrogen replacement markedly attenuated the constriction-increased myocardial chymase, MC density and degranulation, plasma chymase, and myocardial active transforming growth factor-β1, as well as prevented ventricular hypertrophy and increased collagen volume fraction. Chymostatin attenuated the aortic constriction-induced ventricular hypertrophy and collagen volume fraction in the OVX rats similar to that achieved by estrogen replacement. Nedocromil yielded similar effects, except for the reduction of chymase content. We conclude that the estrogen-inhibited release of MC chymase is responsible for the cardioprotection against transverse aortic constriction-induced adverse cardiac remodeling.

  6. Expression of cell surface antigens on mast cells: mast cell phenotyping.

    PubMed

    Hauswirth, Alexander W; Florian, Stefan; Schernthaner, Gerit-Holger; Krauth, Maria-Theresa; Sonneck, Karoline; Sperr, Wolfgang R; Valent, Peter

    2006-01-01

    During the past few decades, a number of functionally important cell surface antigens have been detected on human mast cells (MCs). These antigens include the stem cell factor receptor (SCFR/CD117), the high-affinity immunoglobulin E receptor, adhesion molecules, and activation-linked membrane determinants. Several of these antigens (CD2, CD25, CD35, CD88, CD203c) appear to be upregulated on MCs in patients with systemic mastocytosis and therefore are used as diagnostic markers. Quantitative measurement of these markers on MCs is thus of diagnostic value and is usually performed by multicolor-based flow cytometry techniques utilizing a PE- or APC-labeled antibody against CD117 for MCs detection. This chapter gives an overview about the methods of staining of MC in various tissues with special reference to novel diagnostic markers applied in patients with suspected systemic mastocytosis.

  7. Effects of T cell depletion in radiation bone marrow chimeras. III. Characterization of allogeneic bone marrow cell populations that increase allogeneic chimerism independently of graft-vs-host disease in mixed marrow recipients

    SciTech Connect

    Sykes, M.; Chester, C.H.; Sundt, T.M.; Romick, M.L.; Hoyles, K.A.; Sachs, D.H. )

    1989-12-01

    The opposing problems of graft-vs-host disease vs failure of alloengraftment severely limit the success of allogeneic bone marrow transplantation as a therapeutic modality. We have recently used a murine bone marrow transplantation model involving reconstitution of lethally irradiated mice with mixtures of allogeneic and syngeneic marrow to demonstrate that an allogeneic bone marrow subpopulation, removed by T cell depletion with rabbit anti-mouse brain serum and complement (RAMB/C), is capable of increasing levels of allogeneic chimerism. This effect was observed in an F1 into parent genetic combination lacking the potential for graft-vs-host disease, and radiation protection studies suggested that it was not due to depletion of stem cells by RAMB/C. We have now attempted to characterize the cell population responsible for increasing allogeneic chimerism in this model. The results indicate that neither mature T cells nor NK cells are responsible for this activity. However, an assay involving mixed marrow reconstitution in an Ly-5 congenic strain combination was found to be more sensitive to small degrees of stem cell depletion than radiation protection assays using three-fold titrations of bone marrow cells. Using this assay, we were able to detect some degree of stem cell depletion by treatment with RAMB/C, but not with anti-T cell mAb. Nevertheless, if the effects of alloresistance observed in this model are considered, the degree of stem cell depletion detected by such mixing studies in insufficient to account for the effects of RAMB/C depletion on levels of allogeneic chimerism, suggesting that another cell population with this property remains to be identified.

  8. Human mast cells costimulate T cells through a CD28-independent interaction.

    PubMed

    Suurmond, Jolien; Dorjée, Annemarie L; Huizinga, Tom W J; Toes, René E M

    2016-05-01

    Mast cells are innate immune cells usually residing in peripheral tissues, where they are likely to activate T-cell responses. Similar to other myeloid immune cells, mast cells can function as antigen-presenting cells. However, little is known about the capacity of human mast cells to costimulate CD4(+) T cells. Here, we studied the T-cell stimulatory potential of human mast cells. Peripheral blood derived mast cells were generated and cocultured with isolated CD4(+) T cells. In the presence of T-cell receptor triggering using anti-CD3, mast cells promoted strong proliferation of T cells, which was two- to fivefold stronger than the "T-cell promoting capacity" of monocytes. The interplay between mast cells and T cells was dependent on cell-cell contact, suggesting that costimulatory molecules on the mast cell surface are responsible for the effect. However, in contrast to monocytes, the T-cell costimulation by mast cells was independent of the classical costimulatory molecule CD28, or that of OX40L, ICOSL, or LIGHT. Our data show that mast cells can costimulate human CD4(+) T cells to induce strong T-cell proliferation, but that therapies aiming at disrupting the interaction of CD28 and B7 molecules do not inhibit mast cell mediated T-cell activation.

  9. The production and secretion of complement component C1q by human mast cells.

    PubMed

    van Schaarenburg, Rosanne A; Suurmond, Jolien; Habets, Kim L L; Brouwer, Mieke C; Wouters, Diana; Kurreeman, Fina A S; Huizinga, Tom W J; Toes, René E M; Trouw, Leendert A

    2016-10-01

    C1q is the initiation molecule of the classical pathway of the complement system and is produced by macrophages and immature dendritic cells. As mast cells share the same myeloid progenitor cells, we have studied whether also mast cells can produce and secrete C1q. Mast cells were generated in vitro from CD34+ progenitor cells from buffy coats or cord blood. Fully differentiated mast cells were shown by both RNA sequencing and qPCR to express C1QA, C1QB and C1QC. C1q produced by mast cells has a similar molecular make-up as serum C1q. Reconstituting C1q depleted serum with mast cell supernatant in haemolytic assays, indicated that C1q secreted by mast cells is functionally active. The level of C1q in supernatants produced under basal conditions was considerably enhanced upon stimulation with LPS, dexamethasone in combination with IFN- γ or via FcεRI triggering. Mast cells in human tissues stained positive for C1q in both healthy and in inflamed tissue. Moreover, mast cells in healthy and diseased skin appear to be the predominant C1q positive cells. Together, our data reveal that mast cells are able to produce and secrete functional active C1q and indicate mast cells as a local source of C1q in human tissue.

  10. Ablation of human skin mast cells in situ by lysosomotropic agents.

    PubMed

    Hagforsen, Eva; Paivandy, Aida; Lampinen, Maria; Weström, Simone; Calounova, Gabriela; Melo, Fabio R; Rollman, Ola; Pejler, Gunnar

    2015-07-01

    Mast cells are known to have a detrimental impact on numerous types of inflammatory skin diseases such as contact dermatitis, atopic eczema and cutaneous mastocytosis. Regimens that dampen skin mast cell-mediated activities can thus offer an attractive therapeutic option under such circumstances. As mast cells are known to secrete a large array of potentially pathogenic compounds, both from preformed stores in secretory lysosomes (granules) and after de novo synthesis, mere inhibition of degranulation or interference with individual mast cell mediators may not be sufficient to provide an effective blockade of harmful mast cell activities. An alternative strategy may therefore be to locally reduce skin mast cell numbers. Here, we explored the possibility of using lysosomotropic agents for this purpose, appreciating the fact that mast cell granules contain bioactive compounds prone to trigger apoptosis if released into the cytosolic compartment. Based on this principle, we show that incubation of human skin punch biopsies with the lysosomotropic agents siramesine or Leu-Leu methyl ester preferably ablated the mast cell population, without causing any gross adverse effects on the skin morphology. Subsequent analysis revealed that mast cells treated with lysosomotropic agents predominantly underwent apoptotic rather than necrotic cell death. In summary, this study raises the possibility of using lysosomotropic agents as a novel approach to targeting deleterious mast cell populations in cutaneous mastocytosis and other skin disorders negatively influenced by mast cells.

  11. Masting promotes individual- and population-level reproduction by increasing pollination efficiency.

    PubMed

    Moreira, Xoaquín; Abdala-Roberts, Luis; Linhart, Yan B; Mooney, Kailen A

    2014-04-01

    Masting is a reproductive strategy defined as the intermittent and synchronized production of large seed crops by a plant population. The pollination efficiency hypothesis proposes that masting increases pollination success in plants. Despite its general appeal, no previous studies have used long-term data together with population- and individual-level analyses to assess pollination efficiency between mast and non-mast events. Here we rigorously tested the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa), a long-lived monoecious, wind-pollinated species, using a data set on 217 trees monitored annually for 20 years. Relative investment in male and female function by individual trees did not vary between mast and non-mast years. At both the population and individual level, the rate of production of mature female cones relative to male strobili production was higher in mast than non-mast years, consistent with the predicted benefit of reproductive synchrony on reproductive success. In addition, at the individual level we found a higher conversion of unfertilized female conelets into mature female cones during a mast year compared to a non-mast year. Collectively, parallel results at the population and individual tree level provide robust evidence for the ecological, and potentially also evolutionary, benefits of masting through increased pollination efficiency.

  12. Mast Cell Targeted Chimeric Toxin Can Be Developed as an Adjunctive Therapy in Colon Cancer Treatment.

    PubMed

    Wang, Shan; Li, Linmei; Shi, Renren; Liu, Xueting; Zhang, Junyan; Zou, Zehong; Hao, Zhuofang; Tao, Ailin

    2016-03-11

    The association of colitis with colorectal cancer has become increasingly clear with mast cells being identified as important inflammatory cells in the process. In view of the relationship between mast cells and cancer, we studied the effect and mechanisms of mast cells in the development of colon cancer. Functional and mechanistic insights were gained from ex vivo and in vivo studies of cell interactions between mast cells and CT26 cells. Further evidence was reversely obtained in studies of mast cell targeted Fcε-PE40 chimeric toxin. Experiments revealed mast cells could induce colon tumor cell proliferation and invasion. Cancer progression was found to be related to the density of mast cells in colonic submucosa. The activation of MAPK, Rho-GTPase, and STAT pathways in colon cancer cells was triggered by mast cells during cell-to-cell interaction. Lastly, using an Fcε-PE40 chimeric toxin we constructed, we confirmed the promoting effect of mast cells in development of colon cancer. Mast cells are a promoting factor of colon cancer and thus also a potential therapeutic target. The Fcε-PE40 chimeric toxin targeting mast cells could effectively prevent colon cancer in vitro and in vivo. Consequently, these data may demonstrate a novel immunotherapeutic approach for the treatment of tumors.

  13. Mast Cell Targeted Chimeric Toxin Can Be Developed as an Adjunctive Therapy in Colon Cancer Treatment

    PubMed Central

    Wang, Shan; Li, Linmei; Shi, Renren; Liu, Xueting; Zhang, Junyan; Zou, Zehong; Hao, Zhuofang; Tao, Ailin

    2016-01-01

    The association of colitis with colorectal cancer has become increasingly clear with mast cells being identified as important inflammatory cells in the process. In view of the relationship between mast cells and cancer, we studied the effect and mechanisms of mast cells in the development of colon cancer. Functional and mechanistic insights were gained from ex vivo and in vivo studies of cell interactions between mast cells and CT26 cells. Further evidence was reversely obtained in studies of mast cell targeted Fcε-PE40 chimeric toxin. Experiments revealed mast cells could induce colon tumor cell proliferation and invasion. Cancer progression was found to be related to the density of mast cells in colonic submucosa. The activation of MAPK, Rho-GTPase, and STAT pathways in colon cancer cells was triggered by mast cells during cell-to-cell interaction. Lastly, using an Fcε-PE40 chimeric toxin we constructed, we confirmed the promoting effect of mast cells in development of colon cancer. Mast cells are a promoting factor of colon cancer and thus also a potential therapeutic target. The Fcε-PE40 chimeric toxin targeting mast cells could effectively prevent colon cancer in vitro and in vivo. Consequently, these data may demonstrate a novel immunotherapeutic approach for the treatment of tumors. PMID:26978404

  14. Bone metastasis model with multiorgan dissemination of human small-cell lung cancer (SBC-5) cells in natural killer cell-depleted SCID mice.

    PubMed

    Miki, T; Yano, S; Hanibuchi, M; Sone, S

    2000-01-01

    Lung cancer is commonly associated with multiorgan metastasis, and bone is a frequent metastatic site for lung cancer. Nevertheless, no bone metastasis model of lung cancer with multiorgan dissemination is available, which could provide opportunity to study the molecular pathogenesis. We examined the abilities of eight human lung cancer cell lines injected intravenously into natural killer (NK) cell-depleted SCID mice to generate metastatic nodules in bone and multiple organs, and explored the correlation of the parathyroid hormone-related protein (PTHrP) with the bone metastasis. Although all the small-cell carcinoma cell lines (SBC-5, SBC-3, SBC-3/ADM, H69, H69/VP) formed metastatic nodules in multiple organs (liver, kidney, and lymph nodes), only SBC-5 cells reproducibly developed bone metastases. Squamous cell carcinoma (RERF-LC-AI) cells metastasized mainly into the liver and kidneys, whereas adenocarcinoma (PC-14, A549) mainly produced colonies in the lungs. As assessed by X-ray photography, the osteolytic bone metastases produced by SBC-5 cells were detected as early as on day 28, and all recipient mice developed bone metastasis by day 35. The expression of PTHrP in eight cell lines was directly correlated with the formation of bone metastasis. No correlation was observed between the formation of bone metastasis and the expression of other metastasis-related cytokines (IL-1, IL-6, IL-8, IL-10, IL-11, TNF-alpha, VEGF, M-CSF). Consistent with the formation of bone metastasis by SBC-5 cells, the levels of PTHrP and calcium in the mouse serum were increased in a time-dependent manner, suggesting that PTHrP produced by human lung cancer may play a crucial role in the formation of bone metastasis and hypercalcemia. These findings indicate that a bone metastasis model of SBC-5 cells may be useful for clarifying the molecular aspects of the metastatic processes in different organ microenvironments and the development of therapeutic modalities for lung cancer

  15. HLA-B*57 Elite Suppressor and Chronic Progressor HIV-1 Isolates Replicate Vigorously and Cause CD4+ T Cell Depletion in Humanized BLT Mice

    PubMed Central

    Salgado, Maria; Swanson, Michael D.; Pohlmeyer, Christopher W.; Buckheit, Robert W.; Wu, Jin; Archin, Nancie M.; Williams, Thomas M.; Margolis, David M.; Siliciano, Robert F.

    2014-01-01

    ABSTRACT Elite controllers or suppressors (ES) are HIV-1-infected patients who maintain undetectable viral loads without antiretroviral therapy. The mechanism of control remains unclear, but the HLA-B*57 allele is overrepresented in cohorts of these patients. However, many HLA-B*57 patients develop progressive disease, and some studies have suggested that infection with defective viruses may be the cause of the lack of high levels of virus replication and disease progression in ES. We therefore performed a comprehensive comparative in vivo and in vitro characterization of viruses isolated from well-defined ES. For this purpose, we first performed full-genome sequence analysis and in vitro fitness assays on replication-competent isolates from HLA-B*57 ES and HLA-B*57 chronic progressors (CPs). Under our experimental conditions, we found that isolates from ES and CPs can replicate in vitro. However, since inherently these assays involve the use of unnaturally in vitro-activated cells, we also investigated the replication competence and pathogenic potential of these HIV isolates in vivo using humanized BLT mice. The results from these analyses demonstrate that virus isolates from ES are fully replication competent in vivo and can induce peripheral and systemic CD4 T cell depletion. These results provide the first direct in vivo evidence that viral fitness does not likely determine clinical outcome in HLA-B*57 patients and that elite suppressors can control replication-competent, fully pathogenic viruses. A better understanding of the immunological bases of viral suppression in ES will serve to inform novel approaches to preventive and therapeutic HIV vaccine design. IMPORTANCE Elite suppressors are HIV-1-infected patients who have undetectable levels of viremia despite not being on antiviral drugs. One of the most fundamental questions about this phenomenon involves the mechanism of control. To address this question, we isolated virus from elite suppressors and from

  16. Products from mast cells influence T lymphocyte proliferation and cytokine production--relevant to allergic asthma?

    PubMed

    de Pater-Huijsen, F L; Pompen, M; Jansen, H M; Out, T A

    1997-06-01

    In IgE allergic diseases both mast cells and T lymphocytes play an important role. Whereas mast cels have been implicated in immediate allergic responses, T lymphocytes mediate subsequent late phase responses and chronic inflammation. Here we review possible links between the early mast cell activation and the later T lymphocyte stimulation. Products from mast cells were found to exert effects on T lymphocytes. Human Mast Cell line-1 (HMC-1) mast cells modulated proliferation and cytokine production of a human CD8+ T-cell clone in vitro. Activated mast cells seemed to drive this CD8+ T-cell clone towards a more pronounced T (helper) 1 type of response, simultaneously decreasing T-cell numbers. It is hypothesized that this might be a negative feed back mechanism operating in allergic subjects, by which the Th2-driven IgE production and eosinophilia are counteracted.

  17. 48. CONTROL PANEL FOR UMBILICAL MAST AND TRENCH DOORS. LAUNCHER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. CONTROL PANEL FOR UMBILICAL MAST AND TRENCH DOORS. LAUNCHER ON RIGHT IN BACKGROUND; TRENCH DOORS AND RAIL BEHIND CONTROL PANEL - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. Getting NuSTAR on target: predicting mast motion

    NASA Astrophysics Data System (ADS)

    Forster, Karl; Madsen, Kristin K.; Miyasaka, Hiromasa; Craig, William W.; Harrison, Fiona A.; Rana, Vikram R.; Markwardt, Craig B.; Grefenstette, Brian W.

    2016-07-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing high energy (3-79 keV) X-ray observatory operating for four years from low Earth orbit. The X-ray detector arrays are located on the spacecraft bus with the optics modules mounted on a flexible mast of 10.14m length. The motion of the telescope optical axis on the detectors during each observation is measured by a laser metrology system and matches the pre-launch predictions of the thermal flexing of the mast as the spacecraft enters and exits the Earths shadow each orbit. However, an additional motion of the telescope field of view was discovered during observatory commissioning that is associated with the spacecraft attitude control system and an additional flexing of the mast correlated with the Solar aspect angle for the observation. We present the methodology developed to predict where any particular target coordinate will fall on the NuSTAR detectors based on the Solar aspect angle at the scheduled time of an observation. This may be applicable to future observatories that employ optics deployed on extendable masts. The automation of the prediction system has greatly improved observatory operations efficiency and the reliability of observation planning.

  19. Design and Development of the Space Shuttle Tail Service Masts

    NASA Technical Reports Server (NTRS)

    Dandage, S. R.; Herman, N. A.; Godfrey, S. E.; Uda, R. T.

    1977-01-01

    The successful launch of a space shuttle vehicle depends on the proper operation of two tail service masts (TSMs). Reliable TSM operation is assured through a comprehensive design, development, and testing program. The results of the concept verification test (CVT) and the resulting impact on prototype TSM design are presented. The design criteria are outlined, and the proposed prototype TSM tests are described.

  20. High-throughput charge exchange recombination spectroscopy system on MAST

    SciTech Connect

    Conway, N. J.; Carolan, P. G.; McCone, J.; Walsh, M. J.; Wisse, M.

    2006-10-15

    A major upgrade to the charge exchange recombination spectroscopy system on MAST has recently been implemented. The new system consists of a high-throughput spectrometer coupled to a total of 224 spatial channels, including toroidal and poloidal views of both neutral heating beams on MAST. Radial resolution is {approx}1 cm, comparable to the ion Larmor radius. The toroidal views are configured with 64 channels per beam, while the poloidal views have 32 channels per beam. Background channels for both poloidal and toroidal views are also provided. A large transmission grating is at the heart of the new spectrometer, with high quality single lens reflex lenses providing excellent imaging performance and permitting the full exploitation of the available etendue of the camera sensor. The charge-coupled device camera chosen has four-tap readout at a maximum aggregate speed of 8.8 MHz, and it is capable of reading out the full set of 224 channels in less than 4 ms. The system normally operates at 529 nm, viewing the C{sup 5+} emission line, but can operate at any wavelength in the range of 400-700 nm. Results from operating the system on MAST are shown, including impurity ion temperature and velocity profiles. The system's excellent spatial resolution is ideal for the study of transport barrier phenomena on MAST, an activity which has already been advanced significantly by data from the new diagnostic.

  1. The EUVE Permanent Archive at HEASARC and MAST

    NASA Astrophysics Data System (ADS)

    Christian, D. J.; McGlynn, T.; Drake, S.; White, N. E.; Newman, P.; Postman, M.; Hanisch, R. J.; Donahue, M.; Imhoff, C.; Kimball, T.; Levay, K.; Padovani, P.; Smith, M.; Thompson, R. W.; Malina, R. F.; Stroozas, B.

    2000-05-01

    We present an overview of the EUVE permanent archive data, which is available from the High Energy Astrophysics Science Archive Research Center (HEASARC; http://heasarc.gsfc.nasa.gov/) and accessible through the Multi Mission Archive at Space Telescope Science Institute (MAST; http://archive.stsci.edu/mast.html). The EUVE permanent archive data contains two main data products: 2-dimensional FITS image files of the Deep Survey and spectrometer instruments, and event files for these instruments that include information for temporal analysis. Both archive sites have web retrieval and search pages that allow researchers to search the EUVE holdings by several parameters, including object name, object class, or coordinates. Selected data is easily down-loaded via the web. HEASARC also provides an anonymous ftp option. Both archives include EUVE mission information, data analysis documentation and software, and links to all-sky survey data products. MAST currently has EUVE 1-dimensional quick-look spectra for most EUVE sources, an option to display FITS headers, and/or to down-load spectra in ASCII or FITS formats. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NAG5-7584 and by other grants and contracts.

  2. Clonal mast cell activation syndrome with anaphylaxis to sulfites.

    PubMed

    Cifuentes, Liliana; Ring, Johannes; Brockow, Knut

    2013-01-01

    Sulfites are rarely suspected as causative agents of immediate-type hypersensitivity. We report on a 49-year-old male patient who developed recurrent severe hypotension after food ingestion. A diagnosis of monoclonal mast cell activation syndrome was established. In the double-blind, placebo-controlled food challenge, the patient reacted to potassium metabisulfite with anaphylaxis.

  3. Atherosclerosis: a chronic inflammatory disease mediated by mast cells.

    PubMed

    Conti, Pio; Shaik-Dasthagirisaeb, Yazdami

    2015-01-01

    Inflammation is a process that plays an important role in the initiation and progression of atherosclerosis and immune disease, involving multiple cell types, including macrophages, T-lymphocytes, endothelial cells, smooth muscle cells and mast cells. The fundamental damage of atherosclerosis is the atheromatous or fibro-fatty plaque which is a lesion that causes several diseases. In atherosclerosis the innate immune response, which involves macrophages, is initiated by the arterial endothelial cells which respond to modified lipoproteins and lead to Th1 cell subset activation and generation of inflammatory cytokines and chemoattractant chemokines. Other immune cells, such as CD4+ T inflammatory cells, which play a critical role in the development and progression of atherosclerosis, and regulatory T cells [Treg], which have a protective effect on the development of atherosclerosis are involved. Considerable evidence indicates that mast cells and their products play a key role in inflammation and atherosclerosis. Activated mast cells can have detrimental effects, provoking matrix degradation, apoptosis, and enhancement as well as recruitment of inflammatory cells, which actively contributes to atherosclerosis and plaque formation. Here we discuss the relationship between atherosclerosis, inflammation and mast cells.

  4. VIEW OF TAIL SERVICE MASTS, PORT TSM IN THE FOREGROUND, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF TAIL SERVICE MASTS, PORT TSM IN THE FOREGROUND, FROM THE CORNER WHERE SIDES 1 AND 2 MEET - Cape Canaveral Air Force Station, Launch Complex 39, Mobile Launcher Platforms, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  5. New Kepler Data Products At MAST For Stellar Astrophysics

    NASA Astrophysics Data System (ADS)

    Fleming, Scott W.; Shiao, B.; Tseng, S.; Million, C.; Thompson, R.; Seibert, M.; Abney, F.; Donaldson, T.; Dower, T.; Fraquelli, D. A.; Handy, S.; Koekemoer, A. M.; Levay, K.; Matuskey, J.; McLean, B.; Quick, L.; Rogers, A.; Wallace, G.; White, R. L.

    2014-01-01

    The Kepler Mission has collected high-precision, time-series photometry of over 200,000 stars. The reduced lightcurves, target pixel files, and a variety of catalog metadata are already available at MAST. We present new data products and services at MAST that will further aid researchers as Kepler begins its transition to a legacy mission, particularly in the realm of stellar astrophysics. New photometric catalogs to accompany the Kepler targets have arrived at MAST within the past year, and several more will be coming in the relative future. These include the second half of the Kepler INT survey (U,g,r,i,H_alpha; available now), an improved GALEX source catalog (NUV and FUV; available now), PanSTARRS (g,r,i,z; available soon), and WISE (3.4, 4.6, 12, and 22 microns; planned). We expect searches for variability will become one of the most active areas of archive use, so MAST is including a wide range of variability statistics as part of the archive database. In addition to being searchable through database queries and web forms, each Preview page will now include a summary of these variability indices for each of the target's lightcurves within a Quarter. Along with updated NUV and FUV fluxes, a new tool at MAST called gPhoton will allow users to create time-series lightcurves, including animated movies and intensity images, from any set of GALEX photons with arbitrary aperture and bin sizes. We show some examples of the ways GALEX UV lightcurves generated with gPhoton can be used in conjunction with the Kepler data. Finally, MAST has released an initial version of its Data Discovery Portal. This one-stop, interactive web application gives users the ability to search and access data from any of MAST's missions (HST, GALEX, Kepler, FUSE, IUE, JWST, etc.), as well as any data available through the Virtual Observatory. It includes filtering options, access to interactive displays, an accompanying AstroViewer with data footprints on-sky, the ability to upload your own

  6. Interleukin-33 and Mast Cells Bridge Innate and Adaptive Immunity: From the Allergologist’s Perspective

    PubMed Central

    Jang, Tae Young; Kim, Young Hyo

    2015-01-01

    Interleukin (IL) 33, a member of the IL-1 superfamily, is an “alarmin” protein and is secreted in its active form from damaged cells undergoing necrotic cell death. Mast cells are one of the main effector cell types in allergic disorders. They secrete a variety of mediators, including T helper 2 cytokines. As mast cells have high-affinity IgE receptors (FcεRI) on their surface, they can capture circulating IgE. IgE-bound mast cells degranulate large amounts of histamine, heparin, and proteases when they encounter antigens. As IL-33 is an important mediator of innate immunity and mast cells play an important role in adaptive immune responses, interactions between the two could link innate and adaptive immunity. IL-33 promotes the adhesion of mast cells to laminin, fibronectin, and vitronectin. IL-33 increases the expression of adhesion molecules, such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1, in endothelial cells, thus enhancing mast cell adhesion to blood vessel walls. IL-33 stimulates mast cell proliferation by activating the ST2/Myd88 pathway; increases mast cell survival by the activation of survival proteins such as Bcl-XL; and promotes the growth, development, and maturation of mast cell progenitors. IL-33 is also involved in the activation of mature mast cells and production of different proinflammatory cytokines. The interaction of IL-33 and mast cells could have important clinical implications in the field of clinical urology. Epithelial dysfunction and mast cells could play an important role in the pathogenesis of interstitial cystitis. Urinary levels of IL-33 significantly increase in patients with interstitial cystitis. In addition, the number of mast cells significantly increase in the urinary bladders of patients with interstitial cystitis. Therefore, inhibition of mast cell activation and degranulation in response to increase in IL-33 is a potential therapeutic target in the treatment of interstitial cystitis

  7. Adenine suppresses IgE-mediated mast cell activation.

    PubMed

    Silwal, Prashanta; Shin, Keuna; Choi, Seulgi; Kang, Seong Wook; Park, Jin Bong; Lee, Hyang-Joo; Koo, Suk-Jin; Chung, Kun-Hoe; Namgung, Uk; Lim, Kyu; Heo, Jun-Young; Park, Jong Il; Park, Seung-Kiel

    2015-06-01

    Nucleobase adenine is produced by dividing human lymphoblasts mainly from polyamine synthesis and inhibits immunological functions of lymphocytes. We investigated the anti-allergic effect of adenine on IgE-mediated mast cell activation in vitro and passive cutaneous anaphylaxis (PCA) in mice. Intraperitoneal injection of adenine to IgE-sensitized mice attenuated IgE-mediated PCA reaction in a dose dependent manner, resulting in a median effective concentration of 4.21 mg/kg. In mast cell cultures, only adenine among cytosine, adenine, adenosine, ADP and ATP dose-dependently suppressed FcɛRI (a high affinity receptor for IgE)-mediated degranulation with a median inhibitory concentration of 1.6mM. It also blocked the production of LTB4, an inflammatory lipid mediator, and inflammatory cytokines TNF-α and IL-4. In addition, adenine blocked thapsigargin-induced degranulation which is FcɛRI-independent but shares FcɛRI-dependent signaling events. Adenine inhibited the phosphorylation of signaling molecules important to FcɛRI-mediated allergic reactions such as Syk, PLCγ2, Gab2, Akt, and mitogen activated protein kinases ERK and JNK. From this result, we report for the first time that adenine inhibits PCA in mice and allergic reaction by inhibiting FcɛRI-mediated signaling events in mast cells. Therefore, adenine may be useful for the treatment of mast cell-mediated allergic diseases. Also, the upregulation of adenine production may provide another mechanism for suppressing mast cell activity especially at inflammatory sites.

  8. Cultivation and characterization of canine skin-derived mast cells.

    PubMed

    Kawarai, Shinpei; Masuda, Kenichi; Ohmori, Keitaro; Matsuura, Shinobu; Yasuda, Nobutaka; Nagata, Masahiko; Sakaguchi, Masahiro; Tsujimoto, Hajime

    2010-02-01

    It is essential to develop a technique to culture purified skin-derived mast cells (SMCs) to facilitate immunological research on allergic diseases in dogs. This study was performed to develop an efficient culture system for canine SMCs and to characterize the cells in comparison to canine bone marrow-derived mast cells (BMMCs). Enzymatically digested skin biopsy samples were cultivated in serum-free AIM-V medium supplemented with recombinant canine stem cell factor. Three to five weeks after the initiation of culture, mast cells were collected by a magnetic activated cell separation system using anti-c-Kit antibody. The collected cells were composed of a uniform population showing morphological characteristics of mast cells with a round or oval nucleus and abundant toluidine blue-positive metachromatic granules in the cytoplasm. The results of flow cytometric analysis for the presence of cell membrane c-Kit and Fc epsilon receptor I (FcepsilonRI) indicated that approximately 90% of the cells were mast cells. The cytoplasmic granules were positive for both tryptase and chymase. Apparent dose-dependent degranulation was induced by antibody-mediated cross-linking of immunoglobulin E (IgE) bound to the cells. These cytological and immunological characteristics observed in SMCs were mostly similar to those observed in BMMCs; however, IgE-mediated degranulation was significantly lower in SMCs than BMMCs. The culture system for canine SMCs developed in this study would be useful in understanding the pathophysiology and developing anti-allergic therapeutics in canine allergic dermatitis.

  9. Cutaneous mast cell tumor (Mastocytoma): Cyto- histopathological and haematological investigations

    PubMed Central

    2014-01-01

    Cutaneous mast cell tumours (MCTs) are the most common skin tumours in dogs. Due to the prevalence of canine MCTs and the variable biologic behavior of this disease, accurate prognostication and a thorough understanding of MCT biology are critical for the treatment of this disease. A cytologic diagnosis of mast cell tumor with evidence of prior hemorrhage was made, and the masses were surgically removed. Cytological evaluation of fine-needle aspirates from the cutaneous mass from the axillary comprised many well-differentiated, highly granulated mast cells with moderate numbers of eosinophils. Nuclei were varied in size and shape with high nuclear’to’cytoplasmic ratio, prominent nucleoli, marked atypical and mitotic figures. Microscopically, mass consisted of sheets of neoplastic round cells that formed nonencapsulated nodules in the dermis and infiltrated into the adjacent dermal collagen, and also there was diffuse subcutis invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. In this tumor, cytoplasmic granules showed atypical metachromasia. In addition, eosinophils were scattered among the mast cells at the periphery of the nodules. The presence of eosinophils and the observation, at high magnification, of cells with cytoplasmic metachromatic granules. Invasion of the deep subcutaneous fat or cutaneous muscles were a common feature of grade III tumour. Finally, a diagnosis of grade III cutaneous mast cell tumor was made. Virtual slides The virtual slide(s) of this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4755249151157024. PMID:24444100

  10. Sphingosine-1-phosphate and other lipid mediators generated by mast cells as critical players in allergy and mast cell function.

    PubMed

    Kulinski, Joseph M; Muñoz-Cano, Rosa; Olivera, Ana

    2016-05-05

    Sphingosine-1-phosphate (S1P), platelet activating factor (PAF) and eicosanoids are bioactive lipid mediators abundantly produced by antigen-stimulated mast cells that exert their function mostly through specific cell surface receptors. Although it has long been recognized that some of these bioactive lipids are potent regulators of allergic diseases, their exact contributions to disease pathology have been obscured by the complexity of their mode of action and the regulation of their metabolism. Indeed, the effects of such lipids are usually mediated by multiple receptor subtypes that may differ in their signaling mechanisms and functions. In addition, their actions may be elicited by cell surface receptor-independent mechanisms. Furthermore, these lipids may be converted into metabolites that exhibit different functionalities, adding another layer of complexity to their overall biological responses. In some instances, a second wave of lipid mediator synthesis by both mast cell and non-mast cell sources may occur late during inflammation, bringing about additional roles in the altered environment. New evidence also suggests that bioactive lipids in the local environment can fine-tune mast cell maturation and phenotype, and thus their responsiveness. A better understanding of the subtleties of the spatiotemporal regulation of these lipid mediators, their receptors and functions may aid in the pursuit of pharmacological applications for allergy treatments.

  11. Nicotine inhibits Fc epsilon RI-induced cysteinyl leukotrienes and cytokine production without affecting mast cell degranulation through alpha 7/alpha 9/alpha 10-nicotinic receptors.

    PubMed

    Mishra, Neerad C; Rir-sima-ah, Jules; Boyd, R Thomas; Singh, Shashi P; Gundavarapu, Sravanthi; Langley, Raymond J; Razani-Boroujerdi, Seddigheh; Sopori, Mohan L

    2010-07-01

    Smokers are less likely to develop some inflammatory and allergic diseases. In Brown-Norway rats, nicotine inhibits several parameters of allergic asthma, including the production of Th2 cytokines and the cysteinyl leukotriene LTC(4). Cysteinyl leukotrienes are primarily produced by mast cells, and these cells play a central role in allergic asthma. Mast cells express a high-affinity receptor for IgE (FcepsilonRI). Following its cross-linking, cells degranulate and release preformed inflammatory mediators (early phase) and synthesize and secrete cytokines/chemokines and leukotrienes (late phase). The mechanism by which nicotine modulates mast cell activation is unclear. Using alpha-bungarotoxin binding and quantitative PCR and PCR product sequencing, we showed that the rat mast/basophil cell line RBL-2H3 expresses nicotinic acetylcholine receptors (nAChRs) alpha7, alpha9, and alpha10; exposure to exceedingly low concentrations of nicotine (nanomolar), but not the biologically inactive metabolite cotinine, for > or = 8 h suppressed the late phase (leukotriene/cytokine production) but not degranulation (histamine and hexosaminidase release). These effects were unrelated to those of nicotine on intracellular free calcium concentration but were causally associated with the inhibition of cytosolic phospholipase A(2) activity and the PI3K/ERK/NF-kappaB pathway, including phosphorylation of Akt and ERK and nuclear translocation of NF-kappaB. The suppressive effect of nicotine on the late-phase response was blocked by the alpha7/alpha9-nAChR antagonists methyllycaconitine and alpha-bungarotoxin, as well as by small interfering RNA knockdown of alpha7-, alpha9-, or alpha10-nAChRs, suggesting a functional interaction between alpha7-, alpha9-, and alpha10-nAChRs that might explain the response of RBL cells to nanomolar concentrations of nicotine. This "hybrid" receptor might serve as a target for novel antiallergic/antiasthmatic therapies.

  12. Different radiosensitivities of mast-cell precursors in the bone marrow and skin of mice

    SciTech Connect

    Kitamura, Y.; Yokoyama, M.; Sonoda, T.; Mori, K.J.

    1983-01-01

    Although tissue mast cells are derived from the bone marrow, some descendants of bone marrow-derived precursors retain the ability to proliferate and differentiate into mast cells even after localization in the skin. The purpose of the present study was to determine the D/sub 0/ values for mast-cell precursors in the bone marrow and those localized in the skin. Bone marrow cells were removed from (WB X C57BL/6)F/sub 1/+/+ mice after various doses of irradiation and injected into the skin of the congenic W/W/sup v/ mice which were genetically without mast cells. Radiosensitivity of mast-cell precursors in the bone marrow was evaluated by determining the proportion of the injection sites at which mast cells did not appear. For the assay of the radiosensitivity of mast-cell precursors localized in the skin, pieces of skin were removed from beige C57BL/6 (bg/sup J//bg/sup J/, Chediak-Higashi syndrome) mice after various doses of irradiation and grafted onto the backs of the normal C57BL/6 mice. Radiosensitivity of mast-cell precursors in the skin was evaluated by determining the decrease of beige-type mast cells which possessed giant granules. Mast-cell precursors in the bone marrow were much more radiosenitive than those localized in the skin. D/sup 0/ value was about 100 rad for the former and about 800 rad for the latter.

  13. Different radiosensitivities of mast-cell precursors in the bone marrow and skin of mice

    SciTech Connect

    Kitamura, Y.; Yokoyama, M.; Sonoda, T.; Mori, K.J.

    1983-01-01

    Although tissue mast cells are derived from the bone marrow, some descendants of bone marrow-derived precursors retain the ability to proliferate and differentiate into mast cells even after localization in the skin. The purpose of the present study was to determine the D0 values for mast-cell precursors in the bone marrow and those localized in the skin. Bone marrow cells were removed from (WB X C57BL/6)F1-+/+ mice after various doses of irradiation and injected into the skin of the congenic W/Wv mice which were genetically without mast cells. Radiosensitivity of mast-cell precursors in the bone marrow was evaluated by determining the proportion of the injection sites at which mast cells did not appear. For the assay of the radiosensitivity of mast-cell precursors localized in the skin, pieces of skin were removed from beige C57BL/6 (bgJ/bgJ. Chediak-Higashi syndrome) mice after various doses of irradiation and grafted onto the back of the normal C57BL/6 mice. Radiosensitivity of mast-cell precursors in the skin was evaluated by determining the decrease of beige-type mast cells which possessed giant granules. Mast-cell precursors in the bone marrow were much more radiosensitive than those localized in the skin. D0 value was about 100 rad for the former and about 800 rad for the latter.

  14. Wnt-β-Catenin Signaling Promotes the Maturation of Mast Cells.

    PubMed

    Yamaguchi, Tomoko; Nishijima, Misae; Tashiro, Katsuhisa; Kawabata, Kenji

    2016-01-01

    Mast cells play an important role in the pathogenesis of allergic diseases. Immature mast cells migrate into peripheral tissues from the bone marrow and undergo complete maturation. Interestingly, mast cells have characteristics similar to hematopoietic stem cells (HSCs), such as self-renewal and c-kit expression. In HSCs, Wnt signaling is involved in their maintenance and differentiation. On the other hand, the relation between Wnt signaling and mast cell differentiation is poorly understood. To study whether Wnt signals play a role in the maturation of mast cells, we studied the effect of Wnt proteins on mast cell maturation of bone marrow-derived mast cells (BMMCs). The expression levels of CD81 protein and histidine decarboxylase mRNA and activity of mast cell-specific protease were all elevated in BMMCs treated with Wnt5a. In addition, Wnt5a induced the expression of Axin2 and TCF mRNA in BMMCs. These results showed that Wnt5a could promote the maturation of mast cells via the canonical Wnt signaling pathway and provide important insights into the molecular mechanisms underlying the differentiation of mast cells.

  15. Ultraviolet B radiation increases hairless mouse mast cells in a dose-dependent manner and alters distribution of UV-induced mast cell growth factor.

    PubMed

    Kligman, L H; Murphy, G F

    1996-01-01

    In studies of the effects of chronic UVB irradiation on dermal connective tissue in the hairless mouse, we observed that the number and size of mast cells was increased. Because mast cells are known to be associated with connective tissue remodeling, we examined and quantified the effect of increasing UVB (290-320 nm) doses on this cell. Groups of mice were exposed to filtered FS-40 Westinghouse lamps (290-400 nm: peak irradiance 313 nm) for 1-5 minimal erythema doses (MED) thrice weekly for 10 weeks. Appropriate controls were included. Biopsies, processed for light microscopy, were stained with toluidine blue. Mast cells were counted in 15 high-magnification fields per specimen with upper and lower dermis scored separately. Significant increases in large densely granular mast cells occurred at 2 MED in the lower dermis, in association with a UVB-exacerbated granulomatous reaction. In the upper dermis, mast cells were significantly increased with 3 MED. These findings suggest that mast cells may play a dual role in UV-irradiated skin with those in the lower dermis related to inflammation processes and those in the upper dermis involved in connective tissue modeling. To gain understanding of the mechanism of mast cell recruitment and maturation, we examined the effect of UVB on mast cell growth factor expression. This was enhanced in the epidermis by UVB, with a shift from cytoplasmic staining to membrane-associated or intercellular staining at 2 MED and higher. Dermal dendritic and mononuclear cells also showed increased reactivity.

  16. Prolonged impairment of very late activating antigen-mediated T cell proliferation via the CD3 pathway after T cell-depleted allogeneic bone marrow transplantation.

    PubMed Central

    Sugita, K; Nojima, Y; Tachibana, K; Soiffer, R J; Murray, C; Schlossman, S F; Ritz, J; Morimoto, C

    1994-01-01

    One of the major obstacles in allogeneic bone marrow transplantation (allo-BMT) is prolonged T cell dysfunction resulting in a variety of infectious complications in the months to years after hematologic engraftment. We previously showed that immobilized extracellular matrix (ECM) proteins such as fibronectin (FN), the CS-1 domain of FN, or collagen (CO) acted synergistically with immobilized anti-CD3 to induce T cell proliferation. In addition, the comitogenic effect of ECMs could be mimicked by immobilized mAb reactive with a common beta 1 chain (CD29) of very late activating (VLA) antigens which include ECM receptors. Since the interaction of T cells with ECMs appears to play an important role in the process of T cell reconstitution following allo-BMT, we examined the expression of VLA antigens (alpha 1-alpha 6, beta 1) and their functional roles in CD3-mediated T cell proliferation at various times after T cell depleted allo-BMT. VLA beta 1 as well as VLA alpha 4, alpha 5, and alpha 6 expression was lower than normal controls during the first 3 mo after allo-BMT and auto-BMT, whereas these expressions returned to normal levels by 4 mo after allo-BMT and auto-BMT. Although alpha 1 and alpha 2 were not expressed on lymphocytes from normal controls, these antigens were expressed on lymphocytes at the detectable levels (5-15%) from patients after allo-BMT and auto-BMT. Both CD29 and CD3 were expressed at normal levels on lymphocytes from patients > 3 mo after allo-BMT, whereas T cell interaction with ECM through VLA proteins or crosslinking of VLA beta 1 expressed by T cells with anti-CD29 mAb results in poor induction of CD3-mediated T cell proliferation for a prolonged period (> 1 yr) after allo-BMT. In contrast, T cell proliferation induced by crosslinking of anti-CD2 or anti-CD26 with anti-CD3 was almost fully recovered by 1 yr post-allo-BMT. After autologous BMT, impaired VLA-mediated T cell proliferation via the CD3 pathway after auto-BMT returned to normal

  17. Effect of recombinant human macrophage colony-stimulating factor in irradiated murine recipients of T-cell-depleted allogeneic or non-depleted syngeneic bone marrow transplants.

    PubMed

    Blazar, B R; Aukerman, S L; Vallera, D A

    1992-03-15

    Recombinant macrophage colony-stimulating factor (rM-CSF), which reacts exclusively with cells of monocyte lineage, was evaluated in the murine bone marrow (BM) transplant setting for in vivo effects on recipient survival, hematologic recovery, and engraftment. Two types of fully allogeneic donors were selected based on the expression (BALB/c), or lack of expression (DBA/1), of hybrid hematopoietic histocompatibility (Hh1) antigens. These antigens are established targets for monocyte and/or natural killer (NK) cell-mediated graft rejection. Irradiated C57BL/6 mice were used as recipients for all experiments. Recipients of T-cell-depleted (TCD) BALB/c BM and a 14-day continuous subcutaneous infusion of 16.8 micrograms/d rM-CSF (n = 30) showed a significant decrease in donor cell engraftment as compared with recipients of donor BM administered pumps delivering saline. These mice administered rM-CSF also displayed significantly reduced levels of circulating leukocytes (predominantly lymphocytes) on day 14 posttransplant (compared with saline controls). Neither engraftment effects nor leukocyte effects were observed when C57BL/6 recipients were administered Hh1 nonexpressing TCD DBA/1 BM cells (n = 30), suggesting that the monocyte/macrophage population is important in long-term alloengraftment in certain donor-recipient strain combinations in which donor Hh1 antigens can serve as target antigens for host effector cells, but are not important in strain combinations in which they are not recognized. Circulating tumor necrosis factor alpha (TNF alpha) levels measured at two time periods during rM-CSF infusion were not elevated. Thus, the reduction in alloengraftment is not likely to be directly related to TNF alpha. However, in vivo elimination of NK cells in the BALB/c into C57BL/6 model prevented the impairment of engraftment mediated by rM-CSF. Thus, rM-CSF-mediated inhibition of alloengraftment is contingent on the presence of host NK cells with antidonor reactivity

  18. Induction of Mast Cell Accumulation by Tryptase via a Protease Activated Receptor-2 and ICAM-1 Dependent Mechanism

    PubMed Central

    Liu, Xin; Wang, Junling; Zhang, Huiyun; Zhan, Mengmeng; Chen, Hanqiu; Fang, Zeman; Xu, Chiyan; Chen, Huifang; He, Shaoheng

    2016-01-01

    Mast cells are primary effector cells of allergy, and recruitment of mast cells in involved tissue is one of the key events in allergic inflammation. Tryptase is the most abundant secretory product of mast cells, but little is known of its influence on mast cell accumulation. Using mouse peritoneal model, cell migration assay, and flow cytometry analysis, we investigated role of tryptase in recruiting mast cells. The results showed that tryptase induced up to 6.7-fold increase in mast cell numbers in mouse peritoneum following injection. Inhibitors of tryptase, an antagonist of PAR-2 FSLLRY-NH2, and pretreatment of mice with anti-ICAM-1, anti-CD11a, and anti-CD18 antibodies dramatically diminished tryptase induced mast cell accumulation. On the other hand, PAR-2 agonist peptides SLIGRL-NH2 and tc-LIGRLO-NH2 provoked mast cell accumulation following injection. These implicate that tryptase induced mast cell accumulation is dependent on its enzymatic activity, activation of PAR-2, and interaction between ICAM-1 and LFA-1. Moreover, induction of trans-endothelium migration of mast cells in vitro indicates that tryptase acts as a chemoattractant. In conclusion, provocation of mast cell accumulation by mast cell tryptase suggests a novel self-amplification mechanism of mast cell accumulation. Mast cell stabilizers as well as PAR-2 antagonist agents may be useful for treatment of allergic reactions. PMID:27378825

  19. Cheonggukjang Ethanol Extracts Inhibit a Murine Allergic Asthma via Suppression of Mast Cell-Dependent Anaphylactic Reactions

    PubMed Central

    Bae, Min-Jung; Shin, Hee Soon; See, Hye-Jeong

    2014-01-01

    Abstract Cheonggukjang (CGJ), a traditional Korean fermented soybean food, exerts immunomodulatory effects. Asthma is the most common chronic allergic disease to be associated with immune response to environmental allergens. In the pathogenesis of asthma, histamine is one of the important inflammatory mediators released from granules of mast cells. In this study, we evaluated the therapeutic effect of CGJ on a mouse model of ovalbumin (OVA)-induced asthma via the suppression of histamine release. C57BL/6 mice were sensitized by intraperitoneal injection of OVA or a phosphate-buffered saline (PBS) control and then challenged with OVA inhalation. Mice were treated intraperitoneally with either 70% ethanol-extracted CGJ (CGJE) (100 mg/kg/day) or equivalent PBS. Asthma-related inflammation was assessed by bronchoalveolar lavage fluid cell counts and histopathological and immunohistochemical analysis of lung tissues. To elucidate the mechanisms of asthma inhibition by CGJE treatment, we also examined degranulation and histamine release of compound 48/80-induced rat peritoneal mast cells (RPMCs). Treatment with CGJE downregulated the number of eosinophils and monocytes in the lungs of mice challenged with OVA and suppressed histopathological changes, such as eosinophil infiltration, mucus accumulation, goblet cell hyperplasia, and collagen fiber deposits. Moreover, CGJE alleviated compound 48/80-induced mast cell degranulation and histamine release from RPMCs through inhibition of calcium (Ca2+) uptake as well as ear swelling by infiltration of inflammatory cells. These findings demonstrated that CGJE can be used as an antiasthmatic dietary supplements candidate for histamine-mediated asthma. PMID:24456365

  20. Anti-allergic activity of R-phycocyanin from Porphyra haitanensis in antigen-sensitized mice and mast cells.

    PubMed

    Liu, Qingmei; Wang, Youzhao; Cao, Minjie; Pan, Tzuming; Yang, Yang; Mao, Haiyan; Sun, Lechang; Liu, Guangming

    2015-04-01

    The prevalence of food allergy has increased in Asian countries. Marine algae have been proposed as the potential resource for anti-allergic therapeutics. The present study was aimed at isolating R-phycocyanin (RPC) from Porphyra haitanensis and determining the anti-allergy potential of RPC in antigen-sensitized mice and mast cells. In animal experiments, RPC could effectively reduce tropomyosin (TM)-specific immunoglobulin E (IgE) and histamine levels, alleviate allergy symptoms and jejunum tissue inflammation in mice, and inhibit the expression and release of cytokines (interleukin-4 (IL-4) and IL-13) in peritoneal lavage fluid. In spleen lymphocyte experiments, high purity of RPC skewed the immunological function of CD4(+) T cells towards Th1 activity. A higher expression of interferon (IFN)-γ was induced by a synergistic effect of TM and RPC. Through the Jun N-terminal kinase and Janus kinase 2 signaling pathways, IFN-γ synthesis was induced by RPC in combination with TM. Anti-allergic effect of RPC was evaluated in IgE-mediated rat mast RBL-2H3 cells. The results demonstrated that RPC inhibited allergy markers, including the release of β-hexosaminidase, histamine and ROS in antigen-sensitized RBL-2H3 cells. RPC also suppressed the production of pro-inflammatory factors (IL-4 and tumor necrosis factor-α). In conclusion, RPC decreased allergic sensitization against TM by blocking Th2 cell polarization as well as suppressed the release of allergic-mediators in antigen-stimulated mast cells. It may be used as a functional food component or active pharmaceutical ingredient for allergic patients.

  1. FAST Mast Structural Response to Axial Loading: Modeling and Verification

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Elliott, Kenny B.; Templeton, Justin D.; Song, Kyongchan; Rayburn, Jeffery T.

    2012-01-01

    The International Space Station s solar array wing mast shadowing problem is the focus of this paper. A building-block approach to modeling and analysis is pursued for the primary structural components of the solar array wing mast structure. Starting with an ANSYS (Registered Trademark) finite element model, a verified MSC.Nastran (Trademark) model is established for a single longeron. This finite element model translation requires the conversion of several modeling and analysis features for the two structural analysis tools to produce comparable results for the single-longeron configuration. The model is then reconciled using test data. The resulting MSC.Nastran (Trademark) model is then extended to a single-bay configuration and verified using single-bay test data. Conversion of the MSC. Nastran (Trademark) single-bay model to Abaqus (Trademark) is also performed to simulate the elastic-plastic longeron buckling response of the single bay prior to folding.

  2. Cardiovascular symptoms in patients with systemic mast cell activation disease.

    PubMed

    Kolck, Ulrich W; Haenisch, Britta; Molderings, Gerhard J

    2016-08-01

    Traditionally, mast cell activation disease (MCAD) has been considered as just one rare (neoplastic) disease, mastocytosis, focused on the mast cell (MC) mediators tryptase and histamine and the suggestive, blatant symptoms of flushing and anaphylaxis. Recently another form of MCAD, the MC activation syndrome, has been recognized featuring inappropriate MC activation with little to no neoplasia and likely much more heterogeneously clonal and far more prevalent than mastocytosis. Increasing expertise and appreciation has been established for the truly very large menagerie of MC mediators and their complex patterns of release, engendering complex, nebulous presentations of chronic and acute illness best characterized as multisystem polymorbidity of generally inflammatory ± allergic theme. We describe the pathogenesis of MCAD with a particular focus on clinical cardiovascular symptoms and the therapeutic options for MC mediator-induced cardiovascular symptoms.

  3. Influence of antenna aiming on ECE in MAST

    SciTech Connect

    Preinhaelter, Josef; Urban, Jakub; Pavlo, Pavol; Shevchenko, Vladimir; Valovic, Martin; Vahala, Linda; Vahala, George

    2004-10-01

    The effect of the direction of the detected beam on the intensity of ECE is studied. It is found that the combined effects of the strong dependence of the conversion efficiencey of O mode at the plasma resonance on the direction of the incident wave and the partial screening of the beam waist by the MAST vessel wall, can be responsible for the weakening of ECE emission for some frequencies. The theoretical model for ECE data interpretation on MAST has been significantly improved. New features of the model are as follows: the quasioptical treatment of the receiving antenna, interference, polarization and screening effects of the vacuum window and collisional damping of EBWs in the peripheral plasma.

  4. Conceptual design of a neutron camera for MAST Upgrade

    SciTech Connect

    Weiszflog, M. Sangaroon, S.; Cecconello, M.; Conroy, S.; Ericsson, G.; Klimek, I.; Keeling, D.; Martin, R.; Turnyanskiy, M.

    2014-11-15

    This paper presents two different conceptual designs of neutron cameras for Mega Ampere Spherical Tokamak (MAST) Upgrade. The first one consists of two horizontal cameras, one equatorial and one vertically down-shifted by 65 cm. The second design, viewing the plasma in a poloidal section, also consists of two cameras, one radial and the other one with a diagonal view. Design parameters for the different cameras were selected on the basis of neutron transport calculations and on a set of target measurement requirements taking into account the predicted neutron emissivities in the different MAST Upgrade operating scenarios. Based on a comparison of the cameras’ profile resolving power, the horizontal cameras are suggested as the best option.

  5. Conceptual design of a neutron camera for MAST Upgrade.

    PubMed

    Weiszflog, M; Sangaroon, S; Cecconello, M; Conroy, S; Ericsson, G; Klimek, I; Keeling, D; Martin, R; Turnyanskiy, M

    2014-11-01

    This paper presents two different conceptual designs of neutron cameras for Mega Ampere Spherical Tokamak (MAST) Upgrade. The first one consists of two horizontal cameras, one equatorial and one vertically down-shifted by 65 cm. The second design, viewing the plasma in a poloidal section, also consists of two cameras, one radial and the other one with a diagonal view. Design parameters for the different cameras were selected on the basis of neutron transport calculations and on a set of target measurement requirements taking into account the predicted neutron emissivities in the different MAST Upgrade operating scenarios. Based on a comparison of the cameras' profile resolving power, the horizontal cameras are suggested as the best option.

  6. Research on the fragment impact resistance of a composite mast

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Wu, Chao; Yang, Wenshan; Xu, Shanshan; Ren, Shaofei

    2011-09-01

    Due to the unique structural mode and material property of a composite sandwich plate, related research such as fragment impact resistance of a composite mast is short of publication and urgent in this field. In this paper, the commonly accepted sandwich core board theory was modified. Damage caused by a fragment attack was simulated onto a sandwich plate model built with solid and shell elements. It was shown that shear failure and vast matrix cracking are the main reasons for outer coat damage, and tension failure and partial matrix cracking are the cause for inner coat damage. Additionally, according to complexities in actual sea battles, different work conditions of missile attacks were set. Ballistic limit values of different fragment sizes were also obtained, which provides references for enhancing the fragment impact resistance of a composite mast.

  7. Mast cells: an expanding pathophysiological role from allergy to other disorders.

    PubMed

    Anand, Preet; Singh, Baldev; Jaggi, Amteshwar Singh; Singh, Nirmal

    2012-07-01

    The mast cells are multi-effector cells with wide distribution in the different body parts and traditionally their role has been well-defined in the development of IgE-mediated hypersensitivity reactions including bronchial asthma. Due to the availability of genetically modified mast cell-deficient mice, the broadened pathophysiological role of mast cells in diverse diseases has been revealed. Mast cells exert different physiological and pathophysiological roles by secreting their granular contents, including vasoactive amines, cytokines and chemokines, and various proteases, including tryptase and chymase. Furthermore, mast cells also synthesize plasma membrane-derived lipid mediators, including prostaglandins and leukotrienes, to produce diverse biological actions. The present review discusses the pathophysiological role of mast cells in different diseases, including atherosclerosis, pulmonary hypertension, ischemia-reperfusion injury, male infertility, autoimmune disorders such as rheumatoid arthritis and multiple sclerosis, bladder pain syndrome (interstitial cystitis), anxiety, Alzheimer's disease, nociception, obesity and diabetes mellitus.

  8. Mast cells express novel functional IL-15 receptor alpha isoforms.

    PubMed

    Bulanova, Elena; Budagian, Vadim; Orinska, Zane; Krause, Hans; Paus, Ralf; Bulfone-Paus, Silvia

    2003-05-15

    Mast cells previously have been reported to be regulated by IL-15 and to express a distinct IL-15R, termed IL-15RX. To further examine IL-15 binding and signaling in mast cells, we have studied the nature of the IL-15R and some of its biological activities in these cells. In this study, we report the existence of three novel isoforms of the IL-15R alpha chain in murine bone marrow-derived mast cells as a result of an alternative exon-splicing mechanism within the IL-15R alpha gene. These correspond to new mRNA transcripts lacking exon 4; exons 3 and 4; or exons 3, 4, and 5 (IL-15R alpha Delta 4, IL-15R alpha Delta 3,4, IL-15R alpha Delta 3,4,5). After transient transfection in COS-7 cells, all IL-15R alpha isoforms associate with the Golgi apparatus, the endoplasmic reticulum, the perinuclear space, and the cell membrane. Analysis of glycosylation pattern demonstrates the usage of a single N-glycosylation site, while no O-glycosylation is observed. Importantly, IL-15 binds with high affinity to, and promotes the survival of, murine BA/F3 cells stably transfected with the IL-15R alpha isoforms. Furthermore, we report that signaling mediated by IL-15 binding to the newly identified IL-15R alpha isoforms involves the phosphorylation of STAT3, STAT5, STAT6, Janus kinase 2, and Syk kinase. Taken together, our data indicate that murine mast cells express novel, fully functional IL-15R alpha isoforms, which can explain the selective regulatory effects of IL-15 on these cells.

  9. Autonomous Performance Monitoring System: Monitoring and Self-Tuning (MAST)

    NASA Technical Reports Server (NTRS)

    Peterson, Chariya; Ziyad, Nigel A.

    2000-01-01

    Maintaining the long-term performance of software onboard a spacecraft can be a major factor in the cost of operations. In particular, the task of controlling and maintaining a future mission of distributed spacecraft will undoubtedly pose a great challenge, since the complexity of multiple spacecraft flying in formation grows rapidly as the number of spacecraft in the formation increases. Eventually, new approaches will be required in developing viable control systems that can handle the complexity of the data and that are flexible, reliable and efficient. In this paper we propose a methodology that aims to maintain the accuracy of flight software, while reducing the computational complexity of software tuning tasks. The proposed Monitoring and Self-Tuning (MAST) method consists of two parts: a flight software monitoring algorithm and a tuning algorithm. The dependency on the software being monitored is mostly contained in the monitoring process, while the tuning process is a generic algorithm independent of the detailed knowledge on the software. This architecture will enable MAST to be applicable to different onboard software controlling various dynamics of the spacecraft, such as attitude self-calibration, and formation control. An advantage of MAST over conventional techniques such as filter or batch least square is that the tuning algorithm uses machine learning approach to handle uncertainty in the problem domain, resulting in reducing over all computational complexity. The underlying concept of this technique is a reinforcement learning scheme based on cumulative probability generated by the historical performance of the system. The success of MAST will depend heavily on the reinforcement scheme used in the tuning algorithm, which guarantees the tuning solutions exist.

  10. TRANSP modelling of total and local neutron emission on MAST

    NASA Astrophysics Data System (ADS)

    Klimek, I.; Cecconello, M.; Gorelenkova, M.; Keeling, D.; Meakins, A.; Jones, O.; Akers, R.; Lupelli, I.; Turnyanskiy, M.; Ericsson, G.; the MAST Team

    2015-02-01

    The results of TRANSP simulations of neutron count rate profiles measured by a collimated neutron flux monitor-neutron camera (NC)—for different plasma scenarios on MAST are reported. In addition, the effect of various plasma parameters on neutron emission is studied by means of TRANSP simulation. The fast ion redistribution and losses due to fishbone modes, which belong to a wider category of energetic particle modes, are observed by the NC and modelled in TRANSP.

  11. Rab11 Regulates the Mast Cell Exocytic Response.

    PubMed

    Wilson, Joshua D; Shelby, Sarah A; Holowka, David; Baird, Barbara

    2016-09-01

    Stimulated exocytic events provide a means for physiological communication and are a hallmark of the mast cell-mediated allergic response. In mast cells these processes are triggered by antigen crosslinking of IgE bound to its high-affinity receptor, FcϵRI, on the cell surface. Here we use the endosomal v-SNARE VAMP8, and the lysosomal hydrolase β-hexosaminidase (β-Hex), each C-terminally fused to super-ecliptic pHluorin, to monitor stimulated exocytosis. Using these pHluorin-tagged constructs, we monitor stimulated exocytosis by fluorimetry and visualize individual exocytic events with total internal reflection (TIRF) microscopy. Similar to constitutive recycling endosome (RE) trafficking, we find that stimulated RE exocytosis, monitored by VAMP8, is attenuated by expression of dominant negative (S25N) Rab11. Stimulated β-Hex exocytosis is also reduced in the presence of S25N Rab11, suggesting that expression of this mutant broadly impacts exocytosis. Interestingly, pretreatment with inhibitors of actin polymerization, cytochalasin D or latrunculin A, substantially restores both RE and lysosome exocytosis in cells expressing S25N Rab11. Conversely, stabilizing F-actin with jasplakinolide inhibits antigen-stimulated exocytosis but is not additive with S25N Rab11-mediated inhibition, suggesting that these reagents inhibit related processes. Together, our results suggest that Rab11 participates in the regulation necessary for depolymerization of the actin cytoskeleton during stimulated exocytosis in mast cells.

  12. Release of histamine from mast cells by a synthetic ionophore

    SciTech Connect

    Atkinson, T.P.; Smith, T.F.; Hunter, R.L.

    1986-03-01

    Polyphore 27:10 is a copolymer composed of blocks of polyoxyethylene and polyoxypropylene. Subcutaneous injection of this copolymer in mice causes significant inflammation as determined by footpad swelling and increased vascular permeability as measured by extravasation of Evan's blue dye. Micromolar concentrations trigger release of histamine from purified mouse mast cells and human peripheral blood basophils in vitro. Histamine release from murine mast cells required physiologic temperature, metabolic energy, and calcium ions in the surrounding medium. Replacement of sodium ions in the medium with either potassium or lithium markedly inhibited release. Since Polyphore 27:10 has structural homology with ethylenediamine tetraacetic acid (EDTA) and the crown polyethers, both of which chelate metal ions, The authors investigated whether Polyphore 27:10 could act as an ionophore. The Polyphore transported cations across artificial lipid membranes and made erythrocytes highly permeable to sodium ions, but not calcium at physiologic concentrations. They propose that the potent inflammatory and histamine-releasing activities of this copolymer are in part due to its ability to depolarize and degranulate mast cells.

  13. Eigensystem realization algorithm modal identification experiences with mini-mast

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.; Schenk, Axel; Noll, Christopher

    1992-01-01

    This paper summarizes work performed under a collaborative research effort between the National Aeronautics and Space Administration (NASA) and the German Aerospace Research Establishment (DLR, Deutsche Forschungsanstalt fur Luft- und Raumfahrt). The objective is to develop and demonstrate system identification technology for future large space structures. Recent experiences using the Eigensystem Realization Algorithm (ERA), for modal identification of Mini-Mast, are reported. Mini-Mast is a 20 m long deployable space truss used for structural dynamics and active vibration-control research at the Langley Research Center. A comprehensive analysis of 306 frequency response functions (3 excitation forces and 102 displacement responses) was performed. Emphasis is placed on two topics of current research: (1) gaining an improved understanding of ERA performance characteristics (theory vs. practice); and (2) developing reliable techniques to improve identification results for complex experimental data. Because of nonlinearities and numerous local modes, modal identification of Mini-Mast proved to be surprisingly difficult. Methods were available, ERA, for obtaining detailed, high-confidence results.

  14. Inflatable Rigidisable Mast for End-of-Life Deorbiting System

    NASA Astrophysics Data System (ADS)

    Viquerat, A.; Schenk, M.; Sanders, B.; Lappas, V.

    2014-06-01

    An inflatable-rigidisable cylindrical mast was developed as part of the InflateSail technology demonstration mission. The light-weight deployable mast is inflated using a Cool Gas Generator (CGG). To ensure long-term structural performance after deployment, the boom is rigidised by removing the residual creases in the aluminium-laminate skin material through strain- rigidisation. The 1 m long and 90 mm diameter mast is folded using an origami pattern, and in its stowed configuration takes up 63 mm of height in the InflateSail Cube- Sat structure. The benefits of this folding method include minimal material deformation during deployment, a compact stowed configuration, and an open cross-section to accommodate the rapid release of inflation gas. Deployment tests showed a repeatable deployment, with minimal deviation from the intended straight path. Post- deployment vibration experiments established the efficacy of strain-rigidisation in recovering the stiffness of the deployed boom. Experiments were also performed on fully rigidised booms to determine their bending and compression strengths.

  15. Advanced mast cell disease: an Italian Hematological Multicenter experience.

    PubMed

    Pagano, Livio; Valentini, Caterina Giovanna; Caira, Morena; Rondoni, Michela; Van Lint, Maria Teresa; Candoni, Anna; Allione, Bernardino; Cattaneo, Chiara; Marbello, Laura; Caramatti, Cecilia; Pogliani, Enrico Maria; Iannitto, Emilio; Giona, Fiorina; Ferrara, Felicetto; Invernizzi, Rosangela; Fanci, Rosa; Lunghi, Monia; Fianchi, Luana; Sanpaolo, Grazia; Stefani, Pietro Maria; Pulsoni, Alessandro; Martinelli, Giovanni; Leone, Giuseppe; Musto, Pellegrino

    2008-12-01

    The aim of the study is to evaluate clinical features, treatments and outcome of patients with systemic mast cell disease (MCD) who arrived to the attention of hematologists. A retrospective study was conducted over 1995-2006 in patients admitted in 18 Italian hematological divisions. Twenty-four cases of advanced MCD were collected: 12 aggressive SM (50%), 8 mast cell leukemia (33%), 4 SM with associated clonal non-mast cell-lineage hematologic disease (17%). Spleen and liver were the principal extramedullary organ involved. The c-kit point mutation D816V was found in 13/18 patients in which molecular biology studies were performed (72%). Treatments were very heterogeneous: on the whole Imatinib was administered in 17 patients, alpha-Interferon in 8, 2-CdA in 3; 2 patients underwent allogeneic hematopoietic stem cell transplantation. The overall response rate to Imatinib, the most frequently employed drugs, was of 29%, registering one complete remission and four partial remission; all responsive patients did not present D816V c-kit mutation. Overall three patients (12%) died for progression of disease. We conclude that MCD is characterized by severe mediator-related symptoms but with a moderate mortality rate. D816V c-kit mutation is frequent and associated with resistance against Imatinib. Because of the rarity of these forms, an effective standard of care is lacking. More data are needed to find new and successful therapeutic strategies.

  16. Weather model verification using Sodankylä mast measurements

    NASA Astrophysics Data System (ADS)

    Kangas, M.; Rontu, L.; Fortelius, C.; Aurela, M.; Poikonen, A.

    2015-12-01

    Sodankylä, in the heart of Arctic Research Centre of the Finnish Meteorological Institute (FMI ARC) in northern Finland, is an ideal site for atmospheric and environmental research in the boreal and sub-arctic zone. With temperatures ranging from -50 to +30 °C, it provides a challenging testing ground for numerical weather forecasting (NWP) models as well as weather forecasting in general. An extensive set of measurements has been carried out in Sodankylä for more than 100 years. In 2000, a 48 m high micrometeorological mast was erected in the area. In this article, the use of Sodankylä mast measurements in NWP model verification is described. Started in 2000 with NWP model HIRLAM and Sodankylä measurements, the verification system has now been expanded to include comparisons between 12 NWP models and seven measurement masts. A case study, comparing forecasted and observed radiation fluxes, is also presented. It was found that three different radiation schemes, applicable in NWP model HARMONIE-AROME, produced during cloudy days somewhat different downwelling long-wave radiation fluxes, which however did not change the overall cold bias of the predicted screen-level temperature.

  17. Weather model verification using Sodankylä mast measurements

    NASA Astrophysics Data System (ADS)

    Kangas, Markku; Rontu, Laura; Fortelius, Carl; Aurela, Mika; Poikonen, Antti

    2016-04-01

    Sodankylä, in the heart of Arctic Research Centre of the Finnish Meteorological Institute (FMI ARC) in northern Finland, is an ideal site for atmospheric and environmental research in the boreal and sub-Arctic zone. With temperatures ranging from -50 to +30 °C, it provides a challenging testing ground for numerical weather forecasting (NWP) models as well as weather forecasting in general. An extensive set of measurements has been carried out in Sodankylä for more than 100 years. In 2000, a 48 m-high micrometeorological mast was erected in the area. In this article, the use of Sodankylä mast measurements in NWP model verification is described. Starting in 2000, with the NWP model HIRLAM and Sodankylä measurements, the verification system has now been expanded to include comparisons between 12 NWP models and seven measurement masts, distributed across Europe. A case study, comparing forecasted and observed radiation fluxes, is also presented. It was found that three different radiation schemes, applicable in NWP model HARMONIE-AROME, produced somewhat different downwelling longwave radiation fluxes during cloudy days, which however did not change the overall cold bias of the predicted screen-level temperature.

  18. Mast cells in canine cutaneous hemangioma, hemangiosarcoma and mammary tumors.

    PubMed

    Woldemeskel, Moges; Rajeev, Sreekumari

    2010-02-01

    Mast cell count (MCC) in 45 dogs with cutaneous hemangioma (HA, n = 12), hemangiosarcoma (HSA, n = 12), mammary adenoma (AD, n = 9) and mammary adenocarcinoma (AC, n = 12) was made using Toluidine blue stained sections. Antibodies against endothelial cell markers, Factor VIII and VEGF were used to visualize and determine the hot spot micro-vessel density (MVD). Total MCC and MCC along the invasive edges were significantly higher (p < 0.001) in canine mammary AC than in AD. The total MCC did not significantly differ (p > 0.05), in HSAs (8.6 +/- 3.3) than in HAs (5.5 +/- 2.8). There is a positive correlation (r = 0.14) between the hot spot MCC and MVD in mammary AC, although not significant (p = 0.3172), indicating that mast cells are associated with angiogenesis in canine mammary AC. This study suggests that mast cells may play an important role in neovascularization of canine cutaneous vascular and mammary neoplasms. Detailed studies encompassing correlation of MCC and MVD with clinical outcomes and prognosis in these neoplasms are recommended.

  19. Mast cells express IL-17A in rheumatoid arthritis synovium.

    PubMed

    Hueber, Axel J; Asquith, Darren L; Miller, Ashley M; Reilly, Jim; Kerr, Shauna; Leipe, Jan; Melendez, Alirio J; McInnes, Iain B

    2010-04-01

    The proinflammatory cytokine IL-17A is considered a crucial player in rheumatoid arthritis (RA) pathogenesis. In experimental models of autoimmune arthritis, it has been suggested that the cellular source of IL-17A is CD4(+) T cells (Th17 cells). However, little is known about the source of IL-17 in human inflamed RA tissue. We explored the cellular sources of IL-17A in human RA synovium. Surprisingly, only a small proportion of IL-17-expressing cells were T cells, and these were CCR6 negative. Unexpectedly, the majority of IL-17A expression colocalized within mast cells. Furthermore, we demonstrated in vitro that mast cells produced RORC-dependent IL-17A upon stimulation with TNF-alpha, IgG complexes, C5a, and LPS. These data are consistent with a crucial role for IL-17A in RA pathogenesis but suggest that in addition to T cells innate immune pathways particularly mediated via mast cells may be an important component of the effector IL-17A response.

  20. The Role of Mast Cells in Alzheimer's Disease.

    PubMed

    Shaik-Dasthagirisaheb, Yasdani B; Conti, Pio

    2016-01-01

    Immunity and inflammation are deeply involved in Alzheimer's disease. The most important properties of pathological Alzheimer's disease are the extracellular deposits of amyloid â-protein plaque aggregates along with other unknown mutated proteins, which are implicated in immunity and inflammation. Mast cells are found in the brain of all mammalian species and in the periphery, and their biological mediators, including cytokines/chemokines, arachidonic acid products and stored enzymes, play an import role in Alzheimer's disease. Cytokines/chemokines, which are generated mostly by microglia and astrocytes in Alzheimer's disease, contribute to nearly every aspect of neuroinflammation and amyloid â-protein plaque aggregates may induce in mast cells the release of a plethora of mediators, including pro-inflammatory cytokines/chemokines such as interleukin-1, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-alpha, vascular endothelial growth factor, transforming growth factor beta, CXCL8 and CCL2-3-4. These proinflammatory cytokines/chemokines are prominent mediators of neuroinflammation in brain disorders such as Alzheimer's disease, and their inhibition may be associated with improved recovery. In this review, we summarize the current knowledge regarding the roles of mast cell mediators (stored and de novo synthesis) in the pathogenesis of Alzheimer's disease.

  1. Cold Spray Process Development for the Reclamation of the Apache Helicopter Mast Support

    DTIC Science & Technology

    2009-08-01

    adherent, dense aluminum composite material to repair corrosion damage pits and rebuild the snap ring groove and gear teeth on the mast support on an...restoring back to original dimensions. ..........17 Figure 27. Close up of a corrosion pit filled with cold spray aluminum , machined back to the...gear tooth. A helicopter mast support is shown in figure 1. Figure 1. Aluminum helicopter mast support. 3 3.1 Corrosion Damage Pits The first

  2. IgE Receptor-Mediated Mast-Cell Renin Release

    PubMed Central

    Aldi, Silvia; Robador, Pablo A.; Tomita, Kengo; Di Lorenzo, Annarita; Levi, Roberto

    2015-01-01

    Renin is a newly discovered constituent of mast cells. Given that mast cells play a major role in IgE-mediated allergic hypersensitivity, we investigated whether activation of the high-affinity IgE receptor FcεRI elicits release of mast-cell renin. Cross-linking of FcεRI on the surface of mature bone marrow–derived mast cells elicited release of enzymatically active renin protein. The angiotensin I–forming activity of the renin protein was completely blocked by the selective renin inhibitor BILA 2157, which excludes formation of angiotensin I by proteases other than renin. FcεRI-mediated mast-cell renin release was inhibited by dexamethasone and potentiated by the proinflammatory mediator PGE2. Furthermore, cross-linking of mast-cell FcεRI in ex vivo murine hearts passively sensitized with monoclonal anti-DNP IgE also resulted in mast-cell degranulation and overflow of renin. Our findings indicate that IgE-mediated allergic hypersensitivity provokes release of renin from both cultured and resident cardiac mast cells, a process likely to be exacerbated in a chronic inflammatory background. Given the widespread distribution of mast cells, and the presence of angiotensinogen and angiotensin-converting enzyme in many tissues, renin release in immediate hypersensitivity reactions could result in local angiotensin II generation and multiorgan dysfunctions. PMID:24262755

  3. TLR3-induced activation of mast cells modulates CD8+ T-cell recruitment.

    PubMed

    Orinska, Zane; Bulanova, Elena; Budagian, Vadim; Metz, Martin; Maurer, Marcus; Bulfone-Paus, Silvia

    2005-08-01

    Mast cells play an important role in host defense against various pathogens, but their role in viral infection has not been clarified in detail. dsRNA, synthesized by various types of viruses and mimicked by polyinosinic-polycytidylic acid (poly(I:C)) is recognized by Toll-like receptor 3 (TLR3). In this study, we demonstrate that poly(I:C) injection in vivo potently stimulates peritoneal mast cells to up-regulate a number of different costimulatory molecules. Therefore, we examined the expression and the functional significance of TLR3 activation in mast cells. Mast cells express TLR3 on the cell surface and intracellularly. After stimulation of mast cells with poly(I:C) and Newcastle disease virus (NDV), TLR3 is phosphorylated and the expression of key antiviral response cytokines (interferon beta, ISG15) and chemokines (IP10, RANTES) is upregulated. Interestingly, mast cells activated via TLR3-poly(I:C) potently stimulate CD8+ T-cell recruitment. Indeed, mast-cell-deficient mice (KitW/KitW-v) given an intraperitoneal injection of poly(I:C) show a decreased CD8+ T-cell recruitment, whereas granulocytes normally migrate to the peritoneal cavity. Mast-cell reconstitution of KitW/KitW-v mice normalizes the CD8+ T-cell influx. Thus, mast cells stimulated through engagement of TLR3 are potent regulators of CD8+ T-cell activities in vitro and in vivo.

  4. No Role for Mast Cells in Obesity-Related Metabolic Dysregulation

    PubMed Central

    Chmelař, Jindřich; Chatzigeorgiou, Antonios; Chung, Kyoung-Jin; Prucnal, Marta; Voehringer, David; Roers, Axel; Chavakis, Triantafyllos

    2016-01-01

    Obesity-related adipose tissue (AT) inflammation that promotes metabolic dysregulation is associated with increased AT mast cell numbers. Mast cells are potent inducers of inflammatory responses and could potentially contribute to obesity-induced AT inflammation and metabolic dysregulation. Conflicting findings were reported on obesity-related metabolic dysfunction in mast cell-deficient mice, thus creating a controversy that has not been resolved to date. Whereas traditional Kit hypomorphic mast cell-deficient strains featured reduced diet-induced obesity and diabetes, a Kit-independent model of mast cell deficiency, Cpa3Cre/+ mice, displayed no alterations in obesity and insulin sensitivity. Herein, we analyzed diet-induced obesity in Mcpt5-Cre R-DTA mice, in which the lack of mast cells is caused by a principle different from mast cell deficiency in Cpa3Cre/+ mice or Kit mutations. We observed no difference between mast cell-deficient and -proficient mice in diet-induced obesity with regards to weight gain, glucose tolerance, insulin resistance, metabolic parameters, hepatic steatosis, and AT or liver inflammation. We conclude that mast cells play no essential role in obesity and related pathologies. PMID:27933062

  5. Mast cells in the cytokine network: the what, where from and what for.

    PubMed

    Czarnetzki, B M; Grabbe, J; Kolde, G; Krüger-Krasagakes, S; Welker, P; Zuberbier, T

    1995-08-01

    The basic understanding of mast cell ontogeny and function has been fundamentally changed in recent years with observations that the cells produce and respond to a broad range of cytokines. These rapidly accruing data and their potential significance were discussed at the recent symposium "Mast Cells in the Cytokine Network", and the overview lectures of most speakers are summarized in this special journal issue. In the present introductory manuscript, the organizers of the meeting discuss data fundamental to an understanding of the topic and highlight aspects of special interest. They consider mast cells to be defined most reliably by their unique ultrastructure since the cells are highly heterogeneous in dependence of the species studied, their tissue location, their stage of development and probably also in relation to cytokines. Most other characteristics of mast cells are shared with diverse other cell types. Murine mast cell development is induced by several cytokines. These factors are mostly ineffective in human cells except for stem cell factor which causes mast cell development from CD34+/c-kit+ progenitors. There is however recent evidence that fibroblasts and keratinocytes produce additional growth factors for human mast cells. Regarding cytokine secretion, most molecules known so far are produced by both murine and human mast cells. The cells furthermore bear receptors for several cytokines, enabling them to respond in an autocrine and paracrine fashion. Mast cells may thus function within a complex cytokine network, affecting physiological as well as immunological and inflammatory processes.

  6. Spacelab system analysis: A study of the Marshall Avionics System Testbed (MAST)

    NASA Technical Reports Server (NTRS)

    Ingels, Frank M.; Owens, John K.; Daniel, Steven P.; Ahmad, F.; Couvillion, W.

    1988-01-01

    An analysis of the Marshall Avionics Systems Testbed (MAST) communications requirements is presented. The average offered load for typical nodes is estimated. Suitable local area networks are determined.

  7. An essential role for platelet-activating factor in activating mast cell migration following ultraviolet irradiation

    PubMed Central

    Chacón-Salinas, Rommel; Chen, Limo; Chávez-Blanco, Alma D.; Limón-Flores, Alberto Y.; Ma, Ying; Ullrich, Stephen E.

    2014-01-01

    The UVB (290–320 nm) radiation in sunlight is responsible for inducing skin cancer. Exposure to UV radiation is also immunosuppressive, and the systemic immune suppression induced by UV is a well-recognized risk factor for cancer induction. As UVB radiation is absorbed within the upper layers of the skin, indirect mechanisms must play a role in activating systemic immune suppression. One prominent example is mast cell migration, which from the skin to the draining LN is an essential step in the cascade of events leading to immune suppression. What triggers mast cell migration is not entirely clear. Here, we tested the hypothesis that PAF, a lipid mediator of inflammation produced by the skin in response to UV exposure, is involved. Mast cell-deficient mice (KitW-sh/W-sh) are resistant to the suppressive effect of UV radiation, and reconstituting mast cell-deficient mice with normal bone marrow-derived mast cells restores susceptibility to immunosuppression. However, when mast cells from PAFR−/− mice were used, the reconstituted mice were not susceptible to the suppressive effects of UV. Furthermore, PAFR−/− mice showed impaired UV-induced mast cell migration when compared with WT mice. Finally, injecting PAF into WT mice mimicked the effect of UV irradiation and induced mast cell migration but not in PAFR−/− mice. Our findings indicate that PAFR binding induces mast cells to migrate from the skin to the LNs, where they mediate immune suppression. PMID:24009177

  8. Neutrophil Recruitment by Tumor Necrosis Factor from Mast Cells in Immune Complex Peritonitis

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Ramos, Bernard F.; Jakschik, Barbara A.

    1992-12-01

    During generalized immune complex-induced inflammation of the peritoneal cavity, two peaks of tumor necrosis factor (TNF) were observed in the peritoneal exudate of normal mice. In mast cell-deficient mice, the first peak was undetected, and the second peak of TNF and neutrophil influx were significantly reduced. Antibody to TNF significantly inhibited neutrophil infiltration in normal but not in mast cell-deficient mice. Mast cell repletion of the latter normalized TNF, neutrophil mobilization, and the effect of the antibody to TNF. Thus, in vivo, mast cells produce the TNF that augments neutrophil emigration.

  9. Masting behaviour in a Mediterranean pine tree alters seed predator selection on reproductive output.

    PubMed

    Moreira, X; Abdala-Roberts, L; Zas, R; Merlo, E; Lombardero, M J; Sampedro, L; Mooney, K A

    2016-11-01

    Context-dependency in species interactions is widespread and can produce concomitant patterns of context-dependent selection. Masting (synchronous production of large seed crops at irregular intervals by a plant population) has been shown to reduce seed predation through satiation (reduction in rates of seed predation with increasing seed cone output) and thus represents an important source of context-dependency in plant-animal interactions. However, the evolutionary consequences of such dynamics are not well understood. Here we describe masting behaviour in a Mediterranean model pine species (Pinus pinaster) and present a test of the effects of masting on selection by seed predators on reproductive output. We predicted that masting, by enhancing seed predator satiation, could in turn strengthen positive selection by seed predators for larger cone output. For this we collected six-year data (spanning one mast year and five non-mast years) on seed cone production and seed cone predation rates in a forest genetic trial composed by 116 P. pinaster genotypes. Following our prediction, we found stronger seed predator satiation during the masting year, which in turn led to stronger seed predator selection for increased cone production relative to non-masting years. These findings provide evidence that masting can alter the evolutionary outcome of plant-seed predator interactions. More broadly, our findings highlight that changes in consumer responses to resource abundance represent a widespread mechanism for predicting and understanding context dependency in plant-consumer evolutionary dynamics.

  10. Dexamethasone rapidly suppresses IL-33-stimulated mast cell function by blocking transcription factor activity.

    PubMed

    Paranjape, Anuya; Chernushevich, Oksana; Qayum, Amina Abdul; Spence, Andrew J; Taruselli, Marcela T; Abebayehu, Daniel; Barnstein, Brian O; McLeod, Jamie Josephine Avila; Baker, Bianca; Bajaj, Gurjas S; Chumanevich, Alena P; Oskeritzian, Carole A; Ryan, John J

    2016-12-01

    Mast cells are critical effectors of allergic disease and can be activated by IL-33, a proinflammatory member of the IL-1 cytokine family. IL-33 worsens the pathology of mast cell-mediated diseases, but therapies to antagonize IL-33 are still forthcoming. Because steroids are the mainstay of allergic disease treatment and are well known to suppress mast cell activation by other stimuli, we examined the effects of the steroid dexamethasone on IL-33-mediated mast cell function. We found that dexamethasone potently and rapidly suppressed cytokine production elicited by IL-33 from murine bone marrow-derived and peritoneal mast cells. IL-33 enhances IgE-mediated mast cell cytokine production, an activity that was also antagonized by dexamethasone. These effects were consistent in human mast cells. We additionally observed that IL-33 augmented migration of IgE-sensitized mast cells toward antigen. This enhancing effect was similarly reversed by dexamethasone. Simultaneous addition of dexamethasone with IL-33 had no effect on the phosphorylation of MAP kinases or NFκB p65 subunit; however, dexamethasone antagonized AP-1- and NFκB-mediated transcriptional activity. Intraperitoneal administration of dexamethasone completely abrogated IL-33-mediated peritoneal neutrophil recruitment and prevented plasma IL-6 elevation. These data demonstrate that steroid therapy may be an effective means of antagonizing the effects of IL-33 on mast cells in vitro and in vivo, acting partly by suppressing IL-33-induced NFκB and AP-1 activity.

  11. Suppression of Brain Mast Cells Degranulation Inhibits Microglial Activation and Central Nervous System Inflammation.

    PubMed

    Dong, Hongquan; Zhang, Xiang; Wang, Yiming; Zhou, Xiqiao; Qian, Yanning; Zhang, Shu

    2017-03-01

    Brain inflammation has a critical role in the pathophysiology of brain diseases. Microglia, the resident immune cells in the brain, play an important role in brain inflammation, while brain mast cells are the "first responder" in the injury rather than microglia. Functional aspects of mast cell-microglia interactions remain poorly understood. Our results demonstrated that site-directed injection of the "mast cell degranulator" compound 48/80 (C48/80) in the hypothalamus induced mast cell degranulation, microglial activation, and inflammatory factor production, which initiated the acute brain inflammatory response. "Mast cell stabilizer" disodium cromoglycate (cromolyn) inhibited this effect, including decrease of inflammatory cytokines, reduced microglial activation, inhibition of MAPK and AKT pathways, and repression of protein expression of histamine receptor 1 (H1R), histamine receptor 4 (H4R), protease-activated receptor 2 (PAR2), and toll-like receptor 4 (TLR4) in microglia. We also demonstrated that C48/80 had no effect on microglial activation in mast cell-deficient Kit(W-sh/W-sh) mice. These results implicate that activated brain mast cells trigger microglial activation and stabilization of mast cell inhibits microglial activation-induced central nervous system (CNS) inflammation. Interactions between mast cells and microglia could constitute a new and unique therapeutic target for CNS immune inflammation-related diseases.

  12. Lysophosphatidic acid triggers mast cell-driven atherosclerotic plaque destabilization by increasing vascular inflammation.

    PubMed

    Bot, Martine; de Jager, Saskia C A; MacAleese, Luke; Lagraauw, H Maxime; van Berkel, Theo J C; Quax, Paul H A; Kuiper, Johan; Heeren, Ron M A; Biessen, Erik A L; Bot, Ilze

    2013-05-01

    Lysophosphatidic acid (LPA), a bioactive lysophospholipid, accumulates in the atherosclerotic plaque. It has the capacity to activate mast cells, which potentially exacerbates plaque progression. In this study, we thus aimed to investigate whether LPA contributes to plaque destabilization by modulating mast cell function. We here show by an imaging mass spectrometry approach that several LPA species are present in atherosclerotic plaques. Subsequently, we demonstrate that LPA is a potent mast cell activator which, unlike other triggers, favors release of tryptase. Local perivascular administration of LPA to an atherosclerotic carotid artery segment increases the activation status of perivascular mast cells and promotes intraplaque hemorrhage and macrophage recruitment without impacting plaque cell apoptosis. The mast cell stabilizer cromolyn could prevent intraplaque hemorrhage elicited by LPA-mediated mast cell activation. Finally, the involvement of mast cells in these events was further emphasized by the lack of effect of perivascular LPA administration in mast cell deficient animals. We demonstrate that increased accumulation of LPA in plaques induces perivascular mast cell activation and in this way contributes to plaque destabilization in vivo. This study points to local LPA availability as an important factor in atherosclerotic plaque stability.

  13. Quercetin ameliorates paclitaxel-induced neuropathic pain by stabilizing mast cells, and subsequently blocking PKCε-dependent activation of TRPV1

    PubMed Central

    Gao, Wei; Zan, Yan; Wang, Zai-jie Jim; Hu, Xiao-yu; Huang, Fang

    2016-01-01

    Aim: Severe painful sensory neuropathy often occurs during paclitaxel chemotherapy. Since paclitaxel can activate mast cell and basophils, whereas quercetin, a polyphenolic flavonoid contained in various plants, which can specifically inhibit histamine release as a mast cell stabilizer. In this study we explore whether quercetin could ameliorate paclitaxel-induced neuropathic pain and elucidated the underlying mechanisms. Methods: Quercetin inhibition on histamine release was validated in vitro by detecting histamine release from rat basophilic leukemia (RBL-2H3) cells stimulated with paclitaxel (10 μmol/L). In the in vivo experiments, rats and mice received quercetin (20, 40 mg·kg-1·d-1) for 40 and 12 d, respectively. Meanwhile, the animals were injected with paclitaxel (2 mg/kg, ip) four times on d 1, 3, 5 and 7. Heat hyperalgesia and mechanical allodynia were evaluated at the different time points. The animals were euthanized and spinal cords and dorsal root ganglions were harvested for analyzing PKCε and TRPV1 expression levels. The plasma histamine levels were assessed in rats on d 31. Results: Pretreatment with quercetin (3, 10, 30 μmol/L) dose-dependently inhibited excessive histamine release from paclitaxel-stimulated RBL-2H3 cells in vitro, and quercetin administration significantly suppressed the high plasma histamine levels in paclitaxel-treated rats. Quercetin administration dose-dependently raised the thresholds for heat hyperalgesia and mechanical allodynia in paclitaxel-treated rats and mice. Furthermore, quercetin administration dose-dependently suppressed the increased expression levels of PKCε and TRPV1 in the spinal cords and DRGs of paclitaxel-treated rats and mice. Moreover, quercetin administration may inhibited the translocation of PKCε from the cytoplasm to the membrane in the spinal cord and DRG of paclitaxel-treated rats. Conclusion: Our results reveal the underlying mechanisms of paclitaxel-induced peripheral neuropathy and

  14. Mitigation of MHD induced fast-ion redistribution in MAST and implications for MAST-Upgrade design

    NASA Astrophysics Data System (ADS)

    Keeling, D. L.; Barrett, T. R.; Cecconello, M.; Challis, C. D.; Hawkes, N.; Jones, O. M.; Klimek, I.; McClements, K. G.; Meakins, A.; Milnes, J.; Turnyanskiy, M.; the MAST Team

    2015-01-01

    The phenomenon of the redistribution of neutral beam fast ions due to magnetohydrodynamic (MHD) activity in plasma has been observed on many tokamaks and more recently has been a focus of research on MAST (Turnyanskiy et al 2013 Nucl. Fusion 53 053016). n = 1 fishbone modes are observed to cause a large decrease in the neutron emission rate indicating the existence of a significant perturbation of the fast-ion population in the plasma. Theoretical work on fishbone modes states that the fast-ion distribution itself acts as the source of free energy driving the modes that cause the redistribution. Therefore a series of experiments have been carried out on MAST to investigate a range of plasma densities at two neutral-beam power levels to determine the region within this parameter space in which fishbone activity and consequent fast-ion redistribution is suppressed. Analysis of these experiments shows complete suppression of fishbone activity at high densities with increasing activity and fast-ion redistribution at lower densities and higher neutral-beam power, accompanied by strong evidence that the redistribution effect primarily affects a specific region in the plasma core with a weaker effect over a wider region of the plasma. The results also indicate the existence of correlations between gradients in the modelled fast-ion distribution function, the amplitude and growth rate of the fishbone modes, and the magnitude of the redistribution effect. The same analysis has been carried out on models of MAST-Upgrade baseline plasma scenarios to determine whether significant fast-ion redistribution due to fishbone modes is likely to occur in that device. A simple change to the neutral-beam injector geometry is proposed which is shown to have a significant mitigating effect in terms of the fishbone mode drive and is therefore expected to allow effective plasma heating and current drive over a wider range of plasma conditions in MAST-Upgrade.

  15. Cycloartenyl ferulate, a component of rice bran oil-derived gamma-oryzanol, attenuates mast cell degranulation.

    PubMed

    Oka, T; Fujimoto, M; Nagasaka, R; Ushio, H; Hori, M; Ozaki, H

    2010-02-01

    IgE-targeting therapy could provide significant progress in the treatment of allergic inflammation. In this study, we examined the effect of cycloartenyl ferulate (cycloartenol ferulic acid ester; CAF), a natural product from rice bran oil-derived gamma-oryzanol, on allergic reaction. When CAF and gamma-oryzanol were injected intradermally with anti-DNP IgE into the dorsal skin of rats, the passive cutaneous anaphylaxis reaction induced by DNP-HSA was attenuated. CAF and gamma-oryzanol also inhibited the degranulation of DNP-IgE sensitized RBL-2H3 mast cells stimulated with anti-DNP-HSA. IgE conjugated with CAF could not be detected by anti-IgE antibody in the ELISA analysis. Although incubation of IgE with CAF did not decrease the amount of IgE, it was possible to precipitate IgE by centrifugation. These results demonstrate that CAF captures IgE, prevents it from binding to FcepsilonRI, and attenuates mast cell degranulation.

  16. Hydroethanolic Pistacia atlantica hulls extract improved wound healing process; evidence for mast cells infiltration, angiogenesis and RNA stability.

    PubMed

    Farahpour, Mohammad Reza; Mirzakhani, Navideh; Doostmohammadi, Jamal; Ebrahimzadeh, Mahmood

    2015-05-01

    In Iranian traditional therapy folk, the Pistacia is used for treatment of wound inflammation. Here in the present study, the In vivo effect of Pistacia atlantica hulls ointment (PAO) on the wound healing process was assessed. Excision and incision wounds were induced in rats. Three different doses of PAO were administrated. Following 3, 7, 14 and 21 days, the tissue samples were obtained and skin irritation ratio, hydroxyproline content, as well as immune cells, fibroblasts, fibrocytes distribution and collagen density were analyzed. Moreover, the cellular RNA damage examined using epi-fluorescent microscope. Hydroethanolic extract of PAO significantly (P < 0.05) increased wound contraction percentage and up-regulated hydroxyproline content. The animals in medium and high dose PAO-treated groups exhibited remarkably (P < 0.05) higher fibroblast distribution and significantly (P < 0.05) lower immune cells infiltration. PAO up-regulated mast cells distribution on day 7 and elevated neovascularization in a dose dependent manner. Significantly lower RNA damage was revealed in PAO-treated animals. Our data showed that, PAO shortened the inflammation phase by provoking the fibroblast proliferation. Moreover, PAO enhanced mast cells distribution and infiltration, which in turn promoted the neovascularization. Ultimately, promoted angiogenesis increased RNA stability in different cell types. Thus, Hydroethanolic extract of PAO can be considered as an appropriate compound for wound healing medicine.

  17. An antioxida