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)

Previous studies showed that lung and skin mast cells do not contain eosinophil granule major basic protein (MBP). However, MBP has been localized by immunofluorescence to mast cells from a recently established human mast cell line. Analysis of MBP in human mast cell-1 cell lysates by radioimmunoassay showed immunochemical similarity to eosinophil MBP as judged by comparison of dose-response regression lines. Based on these findings and other new information about mast cell heterogeneity, we tested whether mast cells contain MBP. Mast cells were preserved in Carnoy's fixative and were identified by staining with rhodamine-conjugated avidin or for chloroacetate esterase or aminocaproate esterase activity. MBP was localized by immunofluorescence to mast cells in 6 of 7 nasal polyps, 4 of 4 ileal tissue specimens, and 12 of 14 cutaneous mastocytosis specimens. Furthermore, by immunoelectron microscopy MBP was localized to mast cell granules in cutaneous mastocytosis lesions. In contrast, normal skin mast cells preserved in Carnoy's fixative did not contain MBP. After injection of MBP into normal skin and fixation in Carnoy's fluid, mast cells became MBP-positive within 3 minutes, suggesting that endocytosis of MBP by mast cells had occurred. These results suggest that human mast cells in several tissues may sequester toxic eosinophil proteins by endocytosis.
 ...
PMID:Sequestration of eosinophil major basic protein in human mast cells. 168 35

A cutaneous mastocytoma with associated histologic features of eosinophilic cellulitis is reported. The tumor occurred as a small, asymptomatic lesion on the left thigh of a 4-year-old boy. Microscopically, an accumulation of mast cells, microgranulomas, eosinophils and 'flame figures' was present. A pathogenesis involving mast cell degranulation, eosinophil chemotactic factors and eosinophil major basic protein is discussed.
 ...
PMID:Eosinophilic cellulitis: histologic features in a cutaneous mastocytoma. 190 27

Onchocerciasis patients treated with diethylcarbamazine often undergo a severe inflammatory response, the Mazzotti reaction. To assess the eosinophil's role in the pathogenesis of the Mazzotti reaction, we obtained serial blood, plasma, and skin biopsy specimens from 21 heavily infected patients and 3 endemic controls, both before and during therapy with diethylcarbamazine. Samples were analyzed for blood eosinophils, plasma levels of eosinophil granule major basic protein (MBP) and eosinophil-derived neurotoxin, eosinophil infiltration and eosinophil and mast cell degranulation in the skin. After the first dose of diethylcarbamazine, blood eosinophils fell from a pre-treatment level of 888 +/- 111 to 203 +/- 42 cells/mm3 at 8 h. This decrease was followed by a marked eosinophilia developing over the remaining 7 days of treatment and 14 days of follow-up. Plasma eosinophil-derived neurotoxin levels increased from 56 +/- 4 ng/ml pretreatment to a peak of 82 +/- 9 ng/ml at 8 h and returned to pretreatment levels by 48 h. Beginning at 12 h, plasma MBP levels increased from 730 +/- 74 ng/ml pretreatment to a peak of 1140 +/- 74 ng/ml after 5 days. Pretreatment skin biopsies stained for MBP by immunofluorescence showed a bright fibrillar pattern in the dermis consistent with chronic eosinophil degranulation; the MBP was localized on elastic tissue fibers. After treatment, skin biopsy specimens showed both the pretreatment fibrillar MBP staining pattern as well as focal eosinophil degranulation. Deposition of MBP around microfilariae in the papillary dermis was visible as early as 1.5 h. The lowest blood eosinophil levels and peak plasma eosinophil-derived neurotoxin levels coincided with the infiltration and degranulation of eosinophils in the skin. Mast cell degranulation in the skin was maximal by the first posttreatment biopsy (1.5 h) coincident with the beginning of eosinophil degranulation. Although the pathogenesis of the Mazzotti reaction is clearly complex, our results indicate that eosinophil degranulation is characteristic of the response and that it occurs with a time course suggestive of a role for the eosinophil in determining the clinical and pathologic manifestations of the reaction.
 ...
PMID:Eosinophil degranulation. An immunologic determinant in the pathogenesis of the Mazzotti reaction in human onchocerciasis. 233 37

To investigate the role of the eosinophil in vernal keratoconjunctivitis and contact lens-associated giant papillary conjunctivitis, we assessed the presence of eosinophil granule major basic protein in conjunctival tissues by immunofluorescence. Biopsy specimens of conjunctiva were taken from nine patients with vernal keratoconjunctivitis, seven patients with giant papillary conjunctivitis, and five control subjects. We performed a masked semiquantitative assessment of immunofluorescence on sections from each specimen. The vernal keratoconjunctivitis and giant papillary conjunctivitis groups had significantly (P less than .05) more major basic protein deposition than controls. No significant correlation between severity of disease and degree of major basic protein deposition was found. We found extracellular eosinophil granules in one of three vernal keratoconjunctivitis specimens examined by transmission electron microscopy. Thus, eosinophil degranulation commonly occurs in vernal keratoconjunctivitis and giant papillary conjunctivitis with release of eosinophil granule major basic protein and presumably other toxic granule proteins onto affected tissues. These cationic proteins are potent cytotoxins and are able to stimulate mast cell degranulation.
 ...
PMID:Conjunctival deposition of eosinophil granule major basic protein in vernal keratoconjunctivitis and contact lens-associated giant papillary conjunctivitis. 275 Aug 34

The pathogenesis of ocular allergy involves multiple mechanisms, which lead to mast cell degranulation and the release of chemical mediators. Mast cell mediators that have been implicated in allergic ocular disease include histamine, eosinophil chemotactic factors, eosinophil granule major basic protein, platelet-activating factor, prostaglandin D2, and several other less well-defined preformed or newly synthesized mediators. The release of these chemical mediators ultimately results in conjunctival vasodilation, increased vascular permeability, leukocyte chemotaxis, and, rarely, ocular surface destruction. Current therapy of ocular allergy involves elimination of the offending allergen, modulation of the immune system, and pharmacologic inhibition of the chemical mediators. The purpose of this article is to provide a better understanding of the pathogenesis and current therapy of ocular allergic disorders and to review the central role of the mast cell and chemical mediators involved in ocular allergy.
 ...
PMID:Conjunctivitis of allergic origin: immunologic mechanisms and current approaches to therapy. 790 17

Polymorphic eruption of pregnancy (PEP) and herpes gestationis (HG) are pregnancy-related dermatoses of unknown aetiology with eosinophil infiltration which, at early stages, may show similar clinical and histopathological features. To determine the relative contributions of eosinophils, neutrophils and mast cells to the pathogenesis of PEP and HG through deposition of granule proteins, we studied tissue and serum from 15 patients with PEP and 10 with HG. Using indirect immunofluorescence with antibodies to human eosinophil granule major basic protein (MBP), eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), neutrophil elastase and mast cell tryptase, we determined and compared cellular and extracellular staining patterns in lesional skin biopsy specimens and, using immunoassay, measured MBP, EDN, and ECP in patients' sera. Eosinophil infiltration and extracellular protein deposition of all three eosinophil granule proteins were present in both PEP and HG indicating a pathogenic role for eosinophils in both diseases. Staining for eosinophil granule proteins was especially prominent in urticarial lesions and around blisters in HG. EDN and ECP serum levels in PEP and ECP serum levels in HG were significantly increased compared with those in normal pregnant and normal nonpregnant serum. Neutrophils were more prominent in HG specimens than in PEP specimens; extracellular neutrophil elastase was minimally present and similar in both diseases. Mast cell numbers and extracellular tryptase deposition did not differ between the two diseases and did not differ from mast cell counts in skin of normal pregnant women. This study shows that eosinophil granule proteins are deposited extracellularly in tissue and are increased in serum in both PEP and HG. Moreover, eosinophil involvement in the two diseases is more consistent than neutrophil and mast cell involvement. Comparatively, tissue eosinophil infiltration and extracellular protein deposition is more extensive in HG than in PEP, suggesting that eosinophil involvement is greater in the pathogenesis of HG than PEP and similar to that found in bullous pemphigoid.
 ...
PMID:Polymorphic eruption of pregnancy and herpes gestationis: comparison of granulated cell proteins in tissue and serum. 1035 84

The allergic reaction begins with the antigen-induced aggregation of occupied high-affinity IgE receptors expressed on mast cell surface, their activation, and the release of proinflammatory mediators that cause the "early phase" of this process. In addition, mast cell activation induces the onset of a "late phase" reaction characterized by the tissue infiltration of inflammatory cells, mainly eosinophils. We have hypothesized that during the late phase mast cells interact with and are activated by eosinophils. Here we report that highly purified human lung mast cells became responsive to eosinophil major basic protein (MBP) when in coculture with human lung fibroblasts. In addition, cord blood-derived mast cells maintained in coculture with 3T3 fibroblasts released more histamine and prostaglandin D(2) (PGD(2)) compared with cells maintained in suspension. The fibroblast-derived membrane form of stem cell factor (SCF) was found to be involved in the mast cell increased responsiveness to MBP. In fact, cord blood-derived mast cells cocultured with 3T3 in the presence of antisense for SCF or cocultured with fibroblasts that do not express the membrane form of SCF were inhibited in their histamine-releasing activity toward MBP. In addition, this form of SCF induced the expression of a pertussis toxin-sensitive G(i) protein, G(i3) that interacts with MBP to trigger mast cell non-IgE-dependent activation in a manner similar to other cationic compounds such as compound 48/80. Mast cell responsiveness to eosinophil mediators is a potentially novel evidence for an alternative pathway of allergen-independent activation able to contribute to the perpetuation of allergy.
 ...
PMID:Non-IgE-dependent activation of human lung- and cord blood-derived mast cells is induced by eosinophil major basic protein and modulated by the membrane form of stem cell factor. 1239 3

Human eosinophil granule major basic protein (MBP1) is an exceedingly basic (isoelectric point >11) 14-kDa protein, comprising the core of the secondary eosinophil granule. Recently, a less cationic homolog of MBP, termed MBPH or simply, MBP2, has been discovered. We prepared a panel of mAbs to MBP2 and used these Abs to localize and quantitate this molecule in leukocytes and biological fluids. Specific mAbs for MBP2 were selected using slot-blot analyses and used in a two-site immunoassay, Western blotting, and immunofluorescence microscopy. The sensitivity of the immunoassay was markedly improved by reduction and alkylation of MBP2. MBP1 is more abundant than MBP2 in lysates of eosinophils and their granules, as judged by immunoassay and Western blotting. By immunofluorescence, MBP1 is present in eosinophils, basophils, and a human mast cell line (HMC1), whereas MBP2 is only detected in eosinophils. Neither MBP1 nor MBP2 could be detected in any other peripheral blood leukocyte. MBP2 levels measured in plasma and serum were essentially identical. In contrast to past measurements for MBP1, MBP2 was not detected above normal levels in sera from pregnant donors. However, measurement of serum MBP2 discriminated patients with elevated eosinophils from normal subjects, and MBP2 was also detectable in other biological specimens, such as bronchoalveolar lavage, sputum, and stool. These results indicate that MBP2 is present only in eosinophils and that it may be a useful biomarker for eosinophil-associated diseases.
 ...
PMID:Major basic protein homolog (MBP2): a specific human eosinophil marker. 1708 53

Antigen challenge in sensitized guinea pig esophagus in vitro induces mast cell degranulation and histamine release. This study tests the hypothesis that antigen inhalation in vivo induces infiltration of the esophageal epithelium by mast cells and eosinophils via a histamine pathway. Actively sensitized guinea pigs were exposed to inhaled 0.1% ovalbumin. One or 24 h after inhalation exposure, the esophagus was processed for immunofluorescent staining of mast cell tryptase and eosinophil major basic protein (MBP). Additional animals were pretreated with thioperamide, a histamine H4/H3 receptor antagonist. Total tryptase- and MBP-labeled cells and percent of positive cells in the epithelial layer were counted. The total number of mast cells was unchanged after inhalation challenge, but the percentage in the epithelium increased 1 h after challenge. The total number of eosinophils increased 1 h after challenge, and the percentage migrating to the epithelium increased by 24 h after challenge. Mast cell migration into the mucosal epithelium preceded that of eosinophils. Thioperamide inhibited mast cell and eosinophil migration. In conclusion, antigen inhalation in sensitized animals induces mast cells and eosinophils to infiltrate in the esophageal epithelium via histamine-mediated mechanism.
 ...
PMID:Antigen inhalation induces mast cells and eosinophils infiltration in the guinea pig esophageal epithelium involving histamine-mediated pathway. 1819 52

Eosinophilic esophagitis is characterized by eosinophil-predominant inflammation in the esophagus. How eosinophils migrate and infiltrate into the esophagus, however, is less clear. Our previous study demonstrated that mast cell activation led to eosinophil infiltration in the esophagus. Prostaglandin D2 (PGD2) is an important mediator released from activated mast cells. The present study aims to determine whether PGD2 induces eosinophil infiltration into the esophagus via a d-type prostanoid receptor 2 (DP2) receptor-dependent mechanism. Using an in vivo guinea pig model, PGD2, d-type prostanoid receptor 1 (DP1) agonist, or DP2 agonist were injected into the esophagus. Esophageal tissues were removed 2 hours after injections and proceeded to either hematoxylin-eosin (HE) staining or immunofluorescent staining of eosinophil major basic protein (MBP) to compare each treatment-induced eosinophil infiltration in the esophagus. In a separate study, ovalbumin (OVA)-sensitized guinea pigs were pretreated with either DP2 or DP1 antagonists, followed by inhalation of OVA to induce mast cell activation. Esophageal tissues were then processed for immunofluorescent staining of MBP. PGD2 injection in the esophagus led to an increase of eosinophil infiltration in esophageal epithelium at the injection site as revealed by HE staining. Increased infiltration of eosinophils was further confirmed by the increased presence of MBP-labeled immunopositive (MBP-LI) cells in esophageal epithelium. Injection with DP2 agonist 15(R)-PGD2, but not DP1 agonist BW 245C, mimicked the PGD2-induced response. In OVA-sensitized animals, antigen inhalation increased MBP-LI cells in esophageal epithelium. Pretreatment with DP2 antagonist BAY-u3405, but not DP1 antagonist BW 868C, inhibited the antigen inhalation-induced increase of MBP-LI cells in esophageal epithelium. These data support the hypothesis that PGD2 induces eosinophil trafficking into the esophageal epithelium via a DP2-mediated pathway, suggesting a role of DP2 antagonist in the prevention of eosinophilic esophagitis.
...
PMID:Prostaglandin D2 receptor D-type prostanoid receptor 2 mediates eosinophil trafficking into the esophagus. 2416 71


1 2 Next >>