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

The brains of young adult male and female Sprague-Dawley rats were studied with the electron microscope to determine the full ultrastructural picture of two types of perivascular granular cell. One of these, referred to here as the type I cell and described by both light and electron microscopy by several authors, including ourselves, has been reported to be a mast cell (MC) almost identical to MCs outside the CNS. The other, referred to here as the type II cell and described by many authors under almost as many names, was dealt with fully by Ibrahim in several reports and regarded by him as a type of MC. It is felt that the results warrant the conclusions that the type I cells are indeed MCs, while the type II cells are closely allied to the type I cells and probably better adapted to the function they subserve in the CNS of mammals. The similarities between the two cell types probably outnumber the dissimilarities and even these have their counterparts in MCs outside the CNS. The problem of the possible confusion between the type II cells and macrophages, whether reportedly within vessel walls or in the form of modified or special 'pericytic' microglia, is discussed. It is concluded that there is no justification for regarding these cells as macrophages. Because of the similarity between the type II cells and MCs, and because of the high lipid content of the type II cells, it is suggested that these elements be called neurolipomastocytes or neurolipomastocytoid cells.
 ...
PMID:The mast cells of the mammalian central nervous system. III. Ultrastructural characteristics in the adult rat brain. 44 67

Lesions occurring on the skin and mucous membranes of domestic animals often present both diagnostic challenges and diagnostic confusion. One of the most common causes of confusion is inflammatory lesions that can be mistaken for neoplasia and vice versa. This confusion may emanate from intrinsic biologic variability, histopathologic interpretation, secondary alterations subsequent to inflammation or necrosis, or sampling errors and omission of pertinent information by the clinician. Some diagnostic problems associated with diagnoses of granulomatous inflammation, mesenchymal neoplasia, mast cell tumors, and squamous cell carcinomas are presented, and selected specific differential diagnoses associated with diagnostic problems are discussed.
 ...
PMID:Differential diagnosis of integumentary and mucous membrane lesions. Neoplasia or inflammation? 213 7

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 function, whereas chymase seems to be more involved in inflammatory reactions. This review provides a short overview of the discovery, origin, development, and biological significance of mast cells and will then concentrate on mast cell heterogeneity in rodents and humans with respect to the mast cell proteases tryptase and chymase and their function.
 ...
PMID:Development, significance, and heterogeneity of mast cells with particular regard to the mast cell-specific proteases chymase and tryptase. 906 Apr 46

Mast cells have been suggested to be major effector cells in the immune response to infection with helminths. It is now clear, however, that mast cells are heterogeneous and have a diversity of important functions. In this review, Timothy Lee, Mark Swieter and Dean Befus point out that much of the confusion about the role of mast cells in immunity stems from methods and interpretations which are inadequate for the diversity of roles played by these cells in host responses to parasites. Classical histochemistry may fail to reveal active mast cells, and studies using chemical antagonists are difficult to interpret until we know more about the action of the drugs. The authors show that current research is extending our knowledge of mast cell heterogeneity, and helping to define the powerful array of mediators that they can use to orchestrate the immune response to helminth infections.
 ...
PMID:Mast cell responses to helminth infection. 1546 34

Mast cells generate mediators of inflammation which are stored in granules and secreted on activation either by allergen crosslinking of membrane-bound IgE or through other stimuli. Most methods for mast cell identification rely on the histochemical detection of constituents of the secretory granules. Although staining for mast cells with histochemical stains can be rapid and relatively inexpensive, it is not always possible to distinguish reliably between mast cells and basophils in tissues. A further problem with the staining of mast cells with commonly used basic dyes is that the reagents employed to fix the tissues can influence the results, leading to confusion regarding the numbers of mast cells present in various tissues. Recognition that there is considerable heterogeneity between mast cell populations in the degree to which staining properties are lost with formalin fixation has led to mast cell subsets being defined on this basis. The development and application of procedures for identifying mast cell proteases has led to important advances in our understanding of the role of mast cells and in the nature of heterogeneity in man. The techniques described here should allow the reliable detection of mast cells and mast cell subsets in a range of tissues and cell preparations. There will be a continuing need for validation, for consideration of potential sources of error, and for the development of new and more reliable techniques for mast cell identification.
 ...
PMID:Identification of mast cells and mast cell subpopulations. 1861 17

Systemic mastocytosis is an uncommon condition characterized by abnormal proliferation of mast cells in one or more organ. The specific D816V KIT mutation is present in most cases. Gastrointestinal symptoms occur commonly but histologic characterization of gastrointestinal involvement is incomplete. The purpose of this study was (1) to describe the clinicopathologic features in five patients with systemic mastocytosis involving the gastrointestinal tract and (2) to determine whether gastrointestinal involvement is associated with the usual D816V mutation or a different mutation. Clinical details were obtained from the hospital of origin or referring pathologist. Histologic features were documented in slides stained with hematoxylin and eosin, mast cell tryptase and CD117. Molecular analysis for the D816V KIT mutation was performed on formalin-fixed paraffin-embedded sections. Symptoms included diarrhea/loose stools (n=5), abdominal pain (n=4), vomiting (n=3) and weight loss (n=3). Other findings included cutaneous lesions of mastocytosis (n=4), malabsorption (n=2), hypoalbuminemia (n=2) and constitutional growth delay (n=1). Sites of gastrointestinal involvement included the colon (n=5), duodenum (n=3) and terminal ileum (n=3). Endoscopic/gross findings included mucosal nodularity (n=4), erosions (n=2) and loss of mucosal folds (n=2). In three patients the endoscopic appearance was considered consistent with inflammatory bowel disease. All cases showed increased mast cell infiltration of the lamina propria, confirmed by immunohistochemistry for mast cell tryptase and CD117. In two cases, mast cells had abundant clear cytoplasmic resembling histiocytes. Marked eosinophil infiltrates were present in four patients, in one patient leading to confusion with eosinophilic colitis. Architectural distortion was noted in three cases. The D816V KIT mutation was present in all four cases tested. In conclusion, gastrointestinal involvement by systemic mastocytosis is characterized by a spectrum of morphologic features that can be mistaken for inflammatory bowel disease, eosinophilic colitis or histiocytic infiltrates. Systemic mastocytosis involving the gastrointestinal tract is associated with the usual D816V KIT mutation.
 ...
PMID:Systemic mastocytosis involving the gastrointestinal tract: clinicopathologic and molecular study of five cases. 1893 52

A food allergen may be defined as a substance that reacts with IgE antibodies, induces allergic sensitisation or induces allergic reactions. Some allergens only induce allergic sensitisation but do not provoke symptoms, while others bind IgE but do not induce mast cell degranulation. There is no common structure that can predict whether a given antigen may be a strong food allergen. A complete food allergen, e.g. fish parvalbumin, is capable of stimulating the immune system to produce IgE antibodies, and degranulate mast cells upon subsequent contact. The reason(s) for why some patients with IgE to ovalbumin tolerate eggs, and why some react on one occasion but not on another, are mostly unclear, but may be related to changes in gut permeability induced by other food substances or by gastro-intestinal inflammation prior to the allergen contact. IgE antibodies to fruit or vegetables often show cross-reactivity, due to carbohydrate structures. These cross-reactive glycans have been designated cross-reactive carbohydrate determinants (CCD). Anti-CCD antibodies are highly cross-reactive. The antibodies do not have clinical significant because CCD-containing foods are usually well-tolerated by patients with IgE antibodies to CCD. These IgE antibodies may cause confusion in relation to allergy diagnosis.
 ...
PMID:Food allergens. 2178

Recent progress has begun to reveal the often complex and changing roles of phosphotyrosine and phosphoinositide phosphatases in regulation of immunoreceptor signaling. The resultant confusion has been further increased by discoveries of new players. Here we provide a review of recent progress in defining the roles of these enzymes in immunoreceptor-dependent mast cell, T cell and B cell activation.
...
PMID:Phosphatase regulation of immunoreceptor signaling in T cells, B cells and mast cells. 2368 45

The growing interest in fish models could raise an opportunity to better understand mast cell functions. The piscine mast cell, also known as eosinophilic granular cell, originates from haematopoietic organs, migrates to sites of maturation, and increases in injured tissues. Although there has been confusion arising from the different distribution in fish species and morphological and staining properties, there is a general agreement that the main functional roles, as those exploited in immunity, are quite similar. The aim of this review is to mainly focus on the roles of mast cells in teleost fish disease and in fish models of human diseases, with the attempt to give a comprehensive picture of their role in piscine immune function and their relationship to other immune system cells.
...
PMID:The mast cell plays a central role in the immune system of teleost fish. 2461 88

There has recently been a flurry on the mast cell front caused, not least, by the publication of articles about the IL3-induced growth of mast cells in vitro from haemopoietic tissue. This has left bystanders, and one suspects not a few participants, confused about some of the issues involved. The reason for the confusion lies in the participation of disparate specialities - such as experimental haematology and immunoparasitology - among which communication has not been traditional: however, the revelations raise specific questions which demand an interdisciplinary approach. Thus the evidence is strong that the mast cells derived from cultured haemopoietic tissues are of a special type hitherto called atypical, intestinal or mucosal mast cells (MMC) which are known to occur in profusion in mucous membranes of helminth-infected animals. In this article Ellen Jarrett and David Haig link information about these cells obtained from both in-vivo and in-vitro experiments.
...
PMID:Mucosal mast cells in vivo and in vitro. 2529 6


1 2 Next >>