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)

An acidic proteolytic enzyme which digests host haemoglobin can be isolated and purified from schistosomes. This small glycoprotein is an allergen which sensitizes the host, as shown by immediate hypersensitivity reactions. These are specific for either Schistosoma haematobium or S. mansoni and can be demonstrated by mast cell degranulation in mice or by intradermal skin tests in monkeys. Although high levels of total IgE may be found in acute and chronic schistosomiasis, there was no evident relationship between the worm burden in monkeys and immediate hypersensitivity reactions to either purified enzyme or crude schistosomal extracts. It is suggested that an in vivo correlation between worm burden and manifestations of the allergic response may be perturbed by high titres of non-specific IgE or other homocytotropic antibodies, thus accounting for false negative skin test reactions. Alternatively, a return to low or subnormal IgE levels may allow the restoration of the allergic response, giving rise to false positive reactions. Purified schistosomal antigens offer certain advantages over crude skin test preparations in terms of uniformity of antigen content, dosage and specificity. In addition, the enzyme may represent a species-specific tool for new immunochemical analyses of schistosomiasis.
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PMID:Species specificity of the immediate hypersensitivity to schistosomal proteolytic enzyme. 39 32

Mast cells are known to be present in normal liver tissue but the data on their association with diseases of the liver are limited. In this study we used a long toluidine blue technique to investigate the mast cell numbers in 20 normal and 45 diseased liver biopsies containing granulomas (20 tuberculosis, 14 sarcoidosis, 4 schistosomiasis, 4 neoplasia-associated, 3 drug idiosyncrasy). Our results show that the mast cells are regular constituents of normal portal tracts and the amount of mast cells in the diseased samples corresponds to the area occupied by non-parenchymal tissues. As compared to normal controls, significantly less mast cells were present in biopsies from tuberculosis patients (p less than 0.025). Highest numbers were found in the schistosomiasis group. No link between the mast cell numbers and the cause of the granulomas could be demonstrated.
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PMID:Mast cells in granulomatous liver disease. 159 4

Eosinophil chemotactic activity was detected in the serum obtained at an acute stage of murine schistosomiasis japonica. Gel filtration of the dialyzable fraction of the serum on Sephadex G25 showed that the chemotactic component had an apparent molecular weight of less than 1,000. It was stable to heating, but was sensitive to pronase or carboxypeptidase A digestions, indicating its peptide nature. Eosinophil chemotactic activity of the dialysate of the serum from mast cell-deficient W/Wv mice infected with Schistosoma japonicum was far less than that from normal littermate +/+ mice, although the titers of specific IgE antibody to soluble egg antigen in the serum measured by passive cutaneous anaphylaxis was comparable between them. These results suggest that at least some part of low molecular weight ECF in the circulation seems to be a ECF-A derived from mast cells. Possible biological significance of circulating ECF in schistosomiasis has been discussed.
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PMID:Low molecular weight eosinophil chemotactic factor (ECF) in the serum of murine schistosomiasis japonica. 308 Mar 75

During the schistosomiasis infection there is a "dance of the cells", varying from site to site and related to the time of infection. 1--Eosinophil levels exhibit a bimodal pattern, with the first peak related to the egg deposition and maturation and increased Kupfferian hyperplasia; the second peak precedes the death of some adult worms; 2--The peritoneal eosinophilic levels are inversely proportional to the blood eosinophilic levels; 3--Eosinopoiesis in the bone marrow begins at day 40, reaching the highest levels at day 50 and coincides with hepatic eosinophilic and neutrophilic metaplasia; 4--Peritoneal mast cell levels present a bimodal pattern similar to the blood eosinophils, and inverse to the peritoneal eosinophils. They also show a cyclic behaviour within the hepatic and intestinal granulomas. Integral analysis of the events related to the eosinophils in the blood, bone marrow, peritoneal cavity and hepatic and intestinal granulomas allows the detection of two important eosinophilic phases: the first is due to mobilization and redistribution of the marginal pool and the second originates from eosinophilic production in the bone marrow and liver. The productive phase is characterized by an increase in the number of eosinophils and monocyte/macrophages, and a decrease in neutrophils and stabilization of megakariocytes and erithroid lineages.
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PMID:"In vivo" kinetics of eosinophils and mast cells in experimental murine schistosomiasis. 315 Nov 16

Two neutrophil chemotactic factors were identified in soluble egg antigen preparations of Schistosoma japonicum. The higher-molecular-weight neutrophil chemotactic factor was not separable from eosinophil chemotactic factor by means of gel filtration, anion-exchange chromatography, isoelectric focusing, or affinity chromatography; this neutrophil chemotactic factor is apparently identical to the higher-molecular-weight eosinophil chemotactic factor which we purified previously from the soluble egg antigen. The chemotactic activity of the eosinophil chemotactic factor for neutrophils was stable to periodate oxidation but was notably affected by heating or Pronase digestion, suggesting that the determinant for neutrophil chemotaxis exists on the peptide moiety of the eosinophil chemotactic factor. The lower-molecular-weight neutrophil chemotactic factor was separable from the higher-molecular-weight eosinophil chemotactic factor by gel filtration or anion-exchange chromatography. This neutrophil chemotactic factor was rather hydrophobic and heat-stable, but was sensitive to Pronase or carboxypeptidase A digestion. These results suggest that the receptors on the surfaces of neutrophils and eosinophils for those chemoattractants would be different from each other. We suppose that neutrophil chemotactic factors and eosinophil chemotactic factors from the eggs are responsible for neutrophil and eosinophil accumulation around the eggs in schistosomiasis japonica.
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PMID:Schistosoma japonicum: identification and characterization of neutrophil chemotactic factors from egg antigen. 389 38

In murine schistosomiasis mansoni, a complex series of cell-cell interactions involving T cell subclasses regulates the intensity of the inflammatory granulomatous response. Recent evidence suggests that granuloma mast cells also participate in the regulatory process by the release of histamine. The current study was performed to determine factors that affect the number of granuloma mast cells. More mast cells were detected in liver granulomas from chronically (20-wk) as opposed to acutely (8-wk) infected mice. Adoptive transfer of spleen cells from 20-wk-infected donors into acutely (6-wk) infected recipients increased granuloma mast cell density. Treatment of spleen cells with anti-Thy-1.2 or anti-Lyt-1.1 antiserum and complement, but not anti-Lyt-2.1 or normal mouse serum, abrogated adoptive transfer-induced, augmentation of granuloma mast cell density. Treatment of acutely infected animals with cyclophosphamide or cimetidine (H2 antagonist enhanced granuloma mast cell density. These data suggest that granuloma mast cell density is dependent upon subsets of T lymphocytes.
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PMID:Modulation of granulomatous hypersensitivity. VI. T lymphocyte subsets influence mast cell density in liver granulomas of Schistosoma mansoni-infected mice. 660 49

Factors governing the sensitization or desensitization of basophils and mast cells are discussed. Mathematical models are proposed which illustrate the effects of rising or falling specific or non-specific IgE titres on the tendency of these cells to degranulate. The models presented are consistent with the hypothesis that fine-tuning of the degranulatory event is achieved by one or more of the following mechanisms: alteration of the number of IgE receptors on the mast cell membrane; displacement of specific anti-schistosomal IgE by anti-other-IgE molecules; clipping or otherwise inactivating mast cell-fixed specific IgE receptor sites so as to render these incapable of binding antigen. Mechanisms proposed may explain how a mast cell population may evolve from highly sensitive to non-reactive allergic states during early and/or chronic periods of schistosomiasis, only to revert to highly sensitive states once again, after the disease has been overcome.
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PMID:An analysis of allergy, immunoglobulin E, and diagnostic skin tests in schistosomiasis. 724 40

Serum immunoglobulins were determined in 40 Egyptian patients with schistosomiasis. In addition to the well-established elevation in total IgE, a striking imbalance in the IgG subclass levels was found: IgG3 and IgG4 levels were markedly elevated, whereas IgG2 levels were normal. The IgG4 level did not correlate with the IgG3 level, but a weak correlation between the IgG4 levels and the logarithmic value of the IgE levels was observed (r = 0.49). We determined anti-schistosome antibodies in the IgE and IgG classes and in the IgG4 subclass by a RAST-type of assay. As test antigens an adult worm antigen preparation (AWA) and a soluble egg antigen preparation (SEA) were used. IgE antibodies reacted predominantly with AWA, whereas IgG4 antibodies, especially in patients with recent infections, were directed mainly against SEA. The hypothesis is put forward that the IgG4 antibodies interfere with the effector activities of anti-schistosome antibodies, and thus inhibit complement activation and mast cell triggering.
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PMID:IgG4 antibodies in Egyptian patients with schistosomiasis. 728

Cytokines play a major role in promoting naive Th cells to differentiate into Th1 or Th2 cells. While IL-4 is recognized as the primary pro-Th2 inducing cytokine, the identity of its cellular sources during the development of a Th2 response remains unclear. We have used Schistosoma mansoni eggs, potent stimulators of Th2 responses both during the natural progression of murine schistosomiasis and when experimentally isolated and injected into normal mice, to examine IL-4 production early in the evolution of an Ag-driven Th2 response. Analysis of peritoneal exudate cells by IL-4 specific reverse transcriptase-PCR and ELISPOT, at times following i.p. egg injection in naive C57BL/6 mice, revealed a marked, transient elevation in IL-4 production at 2 to 12 h after Ag exposure. This response was temporally accompanied by eosinophil and neutrophil infiltration and mast cell disappearance. The pattern of early IL-4 production and peritoneal cell infiltration was observed in egg-injected CD4+ cell-depleted and nude C57BL/6 mice, strongly suggesting that a non-T cell is the source of early IL-4 and that the stimulus leading to the egg-induced changes in cellular composition are T cell independent. In addition to IL-4 transcripts, peritoneal exudate cells from egg-injected T cell replete or deficient mice contained IFN-gamma and IL-12 transcripts. Control i.p. PBS injections led to no or minimal cytokine gene transcription. Early IL-4 was predictive of subsequent Th2 response development since, in contrast to C57BL/6 mice, egg-injected BALB/c mice demonstrated no detectable IL-4 production at 12 h and mounted a comparatively weak egg Ag-specific Th2 response.
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PMID:Early IL-4 production by non-CD4+ cells at the site of antigen deposition predicts the development of a T helper 2 cell response to Schistosoma mansoni eggs. 759 87

Mast cells and granulocytes-macrophages (GM) are components of the host defense system against worm infections, including schistosomiasis. Here we report the kinetics of changes in the number of colony-forming cells (CFC) for mast cells and GM during the course of a primary experimental infection of mice with Schistosoma mansoni cercariae over a period of 24 weeks postinfection (p.i.). Concurrently, we measured known myelopoietic and/or mast cell-stimulating cytokines (i.e., interleukin 3 [IL-3] and IL-9) in pokeweed mitogen-activated spleen cell-conditioned medium. Our results show that during the acute phase of the hepatic granulomatous reaction, the numbers of both mast-CFC and GM-CFC were significantly elevated in bone marrow. However, while femoral GM-CFC numbers had returned to normal control values at week 16 p.i., femoral and splenic mast-CFC numbers remained significantly elevated until week 20 p.i., which corresponds to the chronic fibrotic phase of hepatic granulomatous inflammation. Increased GM-CFC numbers correlated with elevated IL-3 levels, while increased mast-CFC numbers paralleled the increased IL-9 concentrations in spleen cell-conditioned medium. By the reverse transcription-PCR method, enhanced expression of IL-3 and IL-9 transcripts was found in RNA samples obtained from livers and spleens of infected mice. Our data demonstrate that during the course of infection of mice with S. mansoni, the coordinate need for mast cells and GM is at least partly regulated at the stage of progenitor cell commitment in the bone marrow and spleen. It appears that IL-3 and IL-9 help to promote at this stage the ultimate generation of mature effector cells.
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PMID:Schistosoma mansoni infection in mice augments the capacity for interleukin 3 (IL-3) and IL-9 production and concurrently enlarges progenitor pools for mast cells and granulocytes-macrophages. 894 33


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