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

Infection of CFW mice with Trichinella spiralis induced a state of relative unresponsiveness to passive cutaneous anaphylaxis (PCA) induced with hen egg albumin and its corresponding antibodies. The unresponsiveness was to PCA produced either with immunoglobulin G1 (IgG1) or IgE type of antibodies, but was more pronounced with the latter. As few as 25 larvae given by stomach tube 20 days before induced this resistance, although 400 larvae induced a greater resistance. When 400 to 600 larvae were fed to mice, the refractoriness of these mice to PCA was noticed 15 days later. The sera of infected mice had the ability to inhibit mainly PCA induced by IgE. This inhibitory property of sera from infected mice was more pronounced 35 days after infection than 10 months later, when only weak inhibitory activity was detected. Purified rat IgE inhibited the PCA reactions induced in both mice and rats with mouse IgE-type antibody. At high concentrations, evidence of inhibition of the IgG1-induced PCA in mice was also obtained. We believe that the relative unresponsiveness of infected mice is due to an increase in production of IgE which competitively blocks the mast cell sites for other IgE molecules.
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PMID:Effect of Trichinella spiralis infection on passive cutaneous anaphylaxis in mice. 83 10

The addition of molybdenum (0.05 mmol kg-1 dry-matter) to the diet of lambs given a trickle infection of Haemonchus contortus larvae (500 third stage larvae d-1 over six weeks) reduced mean faecal egg counts (epg) from 3952 to 2312 +/- 402 by 32 days (P less than 0.02) and greatly reduced the mean number of worms recovered from the abomasum 14 days after infection ceased (907 compared with 4167: P less than 0.01). Infection reduced haemoglobin concentrations less in lambs given molybdenum although the difference was small relative to the reduction in worm burden. Lambs not given molybdenum had low intraepithelial mast cell counts in the abomasal mucosa and less abomasal hypertrophy than expected from abomasal parasitism. Molybdenum did not consistently reduce the copper status of the host or the parasite. Previous exposure to molybdenum greatly reduced protein but not proteinase activity in, or secreted by, adult worms cultured for eight hours. It is suggested that molybdenum either increased the inflammatory response which preceded worm rejection or that it indirectly enhanced that reaction by reducing the effectiveness of copper-dependent, anti-inflammatory enzymes in the gastrointestinal mucosa.
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PMID:Effects of dietary molybdenum on nematode and host during Haemonchus contortus infection in lambs. 158 80

Infection of rats with the parasite Nippostrongylus brasiliensis results in severe intestinal pathology and dysfunction. Much of the damage that occurs within the intestinal tract may be the direct result of the production of potent inflammatory mediators. PAF is one such lipid mediator that may lead to the altered motility and secretory changes that occur during N. brasiliensis infection. Male, Sprague-Dawley rats were subcutaneously infected with 3000 third stage larvae, while control groups were injected with phosphate buffered saline. At various times post infection (4-42 days) groups of four or more infected and control rats were killed and samples of ileum and jejunum were removed for determination of PAF and leukotriene synthesis (LTB4 and LTC4), myeloperoxidase (MPO) activity and tissue eosinophil and mast cell numbers. Separate groups of rats were killed at similar times for the determination of intestinal worm burden and serum rat mast cell protease II (RMCP-II) levels. Significant elevation in PAF synthesis was not seen until day 15, a time when the intestinal worm burden was no longer evident. Furthermore, this elevation was restricted to the jejunum. The elevation in PAF synthesis correlated with a significant elevation in histologically detectable eosinophils and mast cells in the jejunum. Mast cell activity, as detected through serum concentrations of RMCP-II, was significantly elevated at day 8 post-infection and remained elevated until day 18 post-infection. However, despite significant changes in ileal eosinophil and mast cell numbers, PAF synthesis in the ileum did not differ significantly over the course of the infection. LTB4 and LTC4 production and MPO activity, were significantly elevated in both ileum and jejunum only following worm loss. These results demonstrate that PAF synthesis is altered following primary infection with N. brasiliensis. Changes in PAF synthesis paralleled changes in synthesis of other inflammatory mediators and were associated with hyperplasia of various inflammatory cells. Nevertheless, elevated PAF production is not simply a consequence of intestinal eosinophil and mast cell hyperplasia, as ileal PAF production did not significantly change despite hyperplasia of these cell types.
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PMID:Intestinal platelet-activating factor synthesis during Nippostrongylus brasiliensis infection in the rat. 165 65

Intestinal mucosal mast cells (IMMCs) are closely apposed to nerves, which is consistent with other evidence suggesting that mast cells are innervated. Recent studies have indicated that coordinated changes in mast cell and nerve densities occur in the gut mucosa, during progressive fibrosis, but there is a lack of experimental evidence to support remodeling of intestinal nerve fibers as part of a disease process. Infection of rats with the nematode Nippostrongylus brasiliensis (Nb) results in an initial loss of stainable IMMCs, during an acute inflammatory phase, with subsequent mast cell hyperplasia. Accordingly, we employed the Nb model to look for structural neuroplasticity of intestinal mucosal nerves during inflammation. Immunocytochemical labeling of neurofilament subunits was very low in the jejunal mucosa of all animals, whereas neuron-specific enolase (NSE)-immunoreactive nerves were relatively abundant in control animals. The number of NSE-immunoreactive profiles increased approximately 2.5-fold by day 10 (d10) postinfection (p less than 0.01) and returned to near control values by d14. Immunoreactivity for B-50/GAP-43 was more extensive, labeling more than four times the number of nerves per villus, compared with NSE (p less than 0.0001). B-50 immunoreactivity decreased minimally (ca. 20%) by d7 postinfection, and then increased through control values between d10 and d21, to 30% greater than controls at d49 (p less than 0.05). Subclassification of the B-50-immunoreactive nerves according to cross-sectional area revealed a greater than twofold increase in the proportions of large fibers at d7 and d10. Subsequently, the proportions of small nerves were increased compared with controls. The fiber size changes were found to correlate with mast cell densities (r = -0.72 for large and r = 0.76 for small nerves). At d10, dilated B-50- and NSE-immunoreactive nerves predominated, and extraneuronal NSE was noted. Electron microscopy revealed that this was due to axonal dilation and degeneration. These data provide evidence for plasticity of intestinal mucosal nerve fibers during inflammation. This includes early degenerative and later regenerative phases that appear to correlate with mast cell densities. The phenotype of mucosal nerves in control animals suggests ongoing modeling of these fibers.
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PMID:Remodeling of B-50 (GAP-43)- and NSE-immunoreactive mucosal nerves in the intestines of rats infected with Nippostrongylus brasiliensis. 183 18

Small intestinal histopathology and absorption were examined in Beagle puppies infected with either a moderate or a low burden of Toxocara canis. Infection with T. canis significantly reduced absorption of xylose, but only slightly delayed absorption of para-aminobenzoic acid. Fat assimilation was reduced and faecal proteolytic activity was increased. A significant reduction in villous height occurred and was inversely related to the extent of the infection. Villous goblet cell numbers, particularly those in the luminal third of the villus, were lowest and crypt goblet cell numbers were highest in the most heavily infected of the puppies. Villous goblet cell numbers increased rapidly after treatment of the puppies with piperazine or after the spontaneous elimination of the T. canis infection while crypt goblet cell numbers were less affected by elimination of the parasites. Intra-epithelial lymphocyte numbers were lowest in 33- to 37-day-old puppies infected with greater than 127 T. canis and highest in 44- to 46-day-old puppies losing their infection. Infection with T. canis had no apparent effect on mast cell numbers or pyroninophilic cell numbers in the lamina propria.
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PMID:Intestinal changes in puppies infected with Toxocara canis. 191 55

Infection of the bone marrow-derived mast cell line PB-3c with a retrovirus carrying oncogenic c-Ha-ras or v-Ha-ras reduced the interleukin 3 (IL-3) growth requirement and induced a state of tumorigenicity. In contrast, normal c-Ha-ras had no effect on the IL-3 requirement of this cell line nor did the cells become tumorigenic. A factor reduction similar to that caused by activated Ha-ras was transiently obtained with 12-O-tetradecanoylphorbol-13-acetate in the PB-3c cells expressing normal c-Ha-ras. The analogous stimulation of protein kinase C (PKC) in PB-3c cells producing oncogenic Ha-ras led to an additional reduction of the IL-3 requirement during the first 24 h. In the absence of IL-3, the prolonged exposure of the cells to 12-O-tetradecanoylphorbol-13-acetate for 72 h resulted in a stimulation of growth when activated but not when normal Ha-ras was expressed. PB-3c cell lines expressing activated Ha-ras neither revealed differences in the amounts nor in the subcellular distribution of PKC activity but displayed elevated levels of immunoreactive beta-PKC compared to the parental PB-3c cells. Upon 12-O-tetradecanoylphorbol-13-acetate treatment, a protracted down-regulation of the immunodetectable alpha-PKC as well as constitutively high levels of c-fos mRNA were observed when oncogenic Ha-ras was expressed. These data suggest the involvement of specific PKC subtypes and of c-fos in the reduction of the IL-3 requirement caused by activated Ha-ras in this particular hematopoietic cell line.
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PMID:Tumor-promoting phorbol ester and activated Ha-ras synergistically reduce the interleukin 3 requirement in a mast cell line. 198 80

Several studies have indicated that mast cells occur in close proximity to enteric nerves in the gastrointestinal tract of rats, man, and other mammalian species, and such intimate associations have been proposed as one of the anatomical bases of communication between the immune and the nervous systems. However, the specificity of anatomical associations between enteric nerves and mast cells, as opposed to other bone marrow-derived or lymphoid cells normally present in mucosal sites, is unclear. We used transmission electron microscopy to quantify the distances between mast cells and neural processes (nerve terminals or axons) in the small intestinal mucosa, right atrium, skin, and pulmonary parenchyma of normal rats, and in the small intestinal mucosa and lung parenchyma of rats that had undergone hyperplasia of the mast cell populations in these sites as a result of infection with the nematode Nippostrongylus brasiliensis. In the jejunal mucosa of normal rats, 8.0% of mast cells occurred within 100 nm of neural processes and an additional 11.0% between 101 and 500 nm of these structures; the corresponding figures for eosinophils were 3.3% (N.S. vs. mast cell value) and 23.3% (p less than 0.05 vs. mast cell value) and for plasma cells were 8.5% and 14.6% (N.S. vs. mast cell values). In the right atrium, 1.2% of mast cells occurred within 100 nm and an additional 13.4% within 101 and 500 nm of neural processes, whereas no mast cells were observed within 500 nm of neural processes in the pulmonary parenchyma or ear skin. Infection with N. brasiliensis increased by 61% the proportion of mast cells within 500 nm of neural processes in the jejunal mucosa and resulted in the appearance of mast cells in close association with these structures in the jejunal muscularis propria, but had no effect on the proportion of mast cells within 100 or 500 nm of neural processes in the pulmonary parenchyma. Acetylcholine esterase staining demonstrated dense networks of neural processes in the three sites where some mast cells were closely associated with these structures (jejunal mucosa and muscularis, right atrium) but not in the pulmonary parenchyma or ear skin. Taken together, our findings indicate that mast cells occur in close proximity to neural processes in sites where these structures are abundant, but that anatomical associations as close as those between mast cells and neural processes can also occur between such structures and other bone marrow-derived cells (eosinophils) or lymphoid cells (plasma cells) resident in the small intestinal mucosa.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Anatomical variation in mast cell nerve associations in the rat small intestine, heart, lung, and skin. Similarities of distances between neural processes and mast cells, eosinophils, or plasma cells in the jejunal lamina propria. 234 32

We have established an in vitro system with which to examine the ability of Abelson murine leukemia virus (A-MuLV) to infect early hemopoietic progenitor cells. Blast cell colonies containing less than 100 cells were shown to contain up to 85% of cells with secondary hemopoietic colony-forming ability. Infection of cells from these blast colonies resulted in generation of transformed mast cell lines when a feeder was provided. Morphological examination of cells taken from infected cultures at various times postinfection indicated a progression of cellular differentiation to the mast cell lineage. Southern analysis on early subclones of transformed cells from two wells, using a v-abl specific probe, indicated a unique pattern of viral integration amongst subclones, suggesting that all subclones had derived from a single cell in each well. Similar results were observed with helper-free Abelson virus obtained by transfecting psi 2 cells with P160 A-MuLV proviral DNA. These data indicate that hemopoietic progenitor cells can be infected by A-MuLV and subsequently in our in vitro culture condition give rise to transformed mast cell lines.
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PMID:Blast colonies containing hemopoietic progenitor cells can give rise to Abelson virus (A-MuLV)-transformed cell lines. 244

1. The consequences of acute Trypanosoma cruzi infection for acetylcholine and histamine levels in gastric wall and for mast cells of the stomach were studied in rats. 2. Intraperitoneal infection with 4,000 trypomastigotes/g of a Y strain of Trypanosoma cruzi led to a 4-fold decrease in gastric acetylcholine level and to a 57- and 15-fold increase in histamine content in the membranous and glandular regions of the rat stomach, respectively. 3. Infection of rats with Trypanosoma cruzi also induced a 2- and 4-fold increase in mast cell numbers in the membranous and glandular regions of the muscle layer of the gastric wall, respectively, and a ganglionic inflammatory reaction with predominance of mononuclear cells. 4. We conclude that in acutely Trypanosoma cruzi-infected rats, the reduction of acetylcholine content is due to gastric denervation and that the histamine increase might be secondary to gastric denervation and/or to an increase in the number of mast cells of the gastric wall.
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PMID:Gastric acetylcholine and histamine content of normal and Trypanosoma cruzi-infected rats. 251 20

Infections with the nematode Nematospiroides dubius fail to elicit mucosal mast cell (MMC) responses in the intestines of host mice, and suppress MMC responses generated by heterologous infection. Larval N. dubius have the capacity to prime for mastocytosis, and to elicit this response in primed mice during a challenge, but only if adult worms are prevented from developing, either by anthelmintic treatment or by irradiation of the larvae themselves. The suppressive effect of the adult stage was confirmed in experiments where such worms were implanted directly into the intestines of mice primed by exposure to irradiated N. dubius larvae or concurrently infected with Trichinella spiralis. Data on the mechanisms underlying this suppressive effect were obtained from experiments involving the adoptive transfer of mastocytosis by mesenteric lymph node cells (MLNC) from T. spiralis infected mice. When MLNC were taken from mice infected concurrently with both T. spiralis and N. dubius no enhanced mastocytosis was seen in recipients after challenge with T. spiralis. Exposure of MLNC from T. spiralis infected donors to the presence of adult N. dubius after transfer did not reduce the adoptively transferred response. The response was also unaffected when MLNC from adult N. dubius infected mice were simultaneously transferred with MLNC from T. spiralis donors. It is concluded that the suppressive effect of adult N. dubius upon the expression of mucosal mastocytosis acts upon the generation of lymphocytes capable of promoting the development of MMC from precursor cells.
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PMID:Suppression of mucosal mastocytosis by Nematospiroides dubius results from an adult worm-mediated effect upon host lymphocytes. 335 30


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