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)

We examined the mechanisms of quinolone phototoxicity in vivo and in vitro. Simultaneous p.o. administration of a quinolone and ultraviolet-A (UVA) irradiation for 4 h induced auricular skin inflammation in BALB/c mice, including edema and neutrophil infiltration in the dermis. Antioxidants inhibited the inflammation in the early stage and cyclooxygenase inhibitors did in both the early and later stages, whereas 5-lipoxygenase inhibitors or histamine antagonists had no effect. The phototoxic inflammation was also induced in mast cell-deficient WBB6F1-W/Wv mice. Corresponding to the in vivo results, incubation with a quinolone under UVA irradiation stimulated BALB/c 3T3 mouse fibroblast cells to release prostaglandin E2 (PGE2) and 6-keto-PGF1alpha, but not leukotriene B4. In contrast, UVA-pre-irradiated quinolones did not affect PG release from fibroblasts. The PGE2 release was inhibited by cyclooxygenase inhibitors, antioxidants, protein kinase C (PKC) inhibitors and a tyrosine kinase (TK) inhibitor, but not by antibodies against tumor necrosis factor alpha (TNF alpha) and interleukin-1 (IL-1). These results lead to a hypothesis that reactive oxygen species generated from quinolones under UVA irradiation trigger PG release from dermal fibroblasts via PKC and TK activation, resulting in skin inflammation and that 5-lipoxygenase products, histamine, TNF alpha or IL-1 is ruled out from the mechanism.
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PMID:Mechanisms of quinolone phototoxicity. 1002 81

The therapeutic potential of salbutamol, a beta2-adrenergic agonist, was explored in collagen-induced arthritis. This study was based on a report that salbutamol, by elevating intracellular cAMP, inhibits IL-12 production by macrophages and dendritic cells, thus preventing Th1 development. Ten-week-old male DBA/1 mice were immunized by intradermal injection of type II collagen in CFA. Arthritis developed 15-30 days later and the mice were treated after onset of disease with salbutamol, 200 microgram i.p. After 10 days, the mice were sacrificed, and the hind paws were evaluated histologically. Salbutamol, 200 microgram daily or every other day, had a profound therapeutic effect on the clinical progression of arthritis, as assessed by clinical score and paw thickness. The therapeutic effect was dose dependent. Daily administration of 200 microgram of salbutamol offered the best protection against joint damage, as assessed by histology. In vitro, salbutamol reduced IL-12 and TNF-alpha release by peritoneal macrophages in a dose-dependent manner, as well as TNF release by synovial cells from arthritic mice. Ex vivo, draining lymph node cells of the salbutamol-treated arthritic mice showed a diminished CII-specific IFN-gamma production and proliferation. In vivo, salbutamol specifically blocked mast cell degranulation in joint tissues. In conclusion, salbutamol has important effects on the immunoinflammatory response and a significant therapeutic action in collagen-induced arthritis.
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PMID:The beta2-adrenergic agonist salbutamol is a potent suppressor of established collagen-induced arthritis: mechanisms of action. 1022 75

Mast cells can play detrimental roles in the pathophysiology and mortality observed in anaphylaxis and other Th2-dominated allergic diseases. In contrast, these cells contribute to protective host defense mechanisms against parasitic worm infections. After IgE/Ag activation, mast cells can produce multiple cytokines that may enhance allergic inflammations, while a similar panel of Th2-related cytokines may support immunological strategies against parasites. Here we report that in primary mouse bone marrow-derived mast cells activated by ionomycin or IgE/Ag, the proinflammatory mediator IL-1 (alpha or beta) up-regulated production of IL-3, IL-5, IL-6, and IL-9 as well as TNF, i.e., cytokines implicated in many inflammatory processes including those associated with allergies and helminthic infections. IL-1 did not induce significant cytokine release in the absence of ionomycin or IgE/Ag, suggesting that Ca-dependent signaling was required. IL-1-mediated enhancement of cytokine expression was confirmed at the mRNA level by Northern blot and/or RT-PCR analysis. Our study reveals a role for IL-1 in the up-regulation of multiple mast cell-derived cytokines. Moreover, we identify mast cells as a novel source of IL-9. These results are of particular importance in the light of recent reports that strongly support a central role of IL-9 in allergic lung inflammation and in host defense against worm infections.
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PMID:In activated mast cells, IL-1 up-regulates the production of several Th2-related cytokines including IL-9. 1082 Feb 29

Lodoxamid is an antiallergic drug, which stabilizes the mast cells' membrane blocking the release of the type I hypersensitivity reaction chemical mediators. A number of 25 patients with ocular allergic diseases (allergic conjunctivitis, vernal and atopic keratoconjunctivitis, giant papillary conjunctivitis), were included in this study. Lodoxamid, solution 0.1% (Alomide), was given 4 times daily for 6 weeks. The study's aim was to assess the lodoxamid's efficiency, on the ocular signs and symptoms. The study's results showed a significant improvement, or the disappearance of the ocular allergic disease. It is debated upon the lodoxamid's way and place of action, in blocking the type I hypersensitivity reaction. The lodoxamid's efficiency is due to its pharmacological features, by means of which it is effective on many links of the pathogenic chain: mast cells, eosinophils, lymphocytes, neutrophils, antigen presenting cells. Due to its action lodoxamid stabilizes the mast cell's membrane, and inhibits the release of histamine, prostaglandins, leukotrienes, triptase, interleukines -4, -8 and TNF-. During therapy with lodoxamid recruitment and activation of eosinophils is decreased, causing a significant reduction of the basic major protein, cationic eosinophilic protein, eosinophilic derived neurotoxin, eosinophilic peroxidase. Lodoxamid reduces the expression of ICAM-1 on the surface of the antigen presenting cells, and decreases the number of the TH2 cells, from the tears of the allergic patients.
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PMID:[An efficacy study of lodoxamide treatment in allergic eye lesions]. 1102 Nov 10

Although B-1 B cells have received considerable attention, their actual role in the normal functioning of the immune system is unclear. The hypothesized role of B-1 cell IgM in natural protective immunity is just being established. We have uncovered a separate and novel role for B-1 cell IgM in initiating the elicitation of acquired T cell-dependent contact sensitivity (CS), the prototype of in vivo T cell immunity, early after immunization (within 4 days). The recent recognition of a similarly unanticipated role of B cells in a variety of T cell responses, may indicate that B-1 cell IgM has a broader role in immunity than thought previously. We showed that 24 hr CS responses, and rises in local IFN-gamma levels at 24 hrs later after antigen (Ag) challenge the ears, were absent in pan B cell and antibody deficient mice. The mechanism of B cell involvement in CS-initiation is via local C5a generation early (1-2 hrs) after antigen (Ag) challenge of the ears, in 4 day contact sensitized mice. C5a activates local mast cells to release serotonin (5-HT) and TNF alpha to induce endothelial ICAM-1 and VCAM-1, leading to T cell recruitment. We hypothesized that C5a was generated via complement activation due to antibodies forming local AgAb complexes, and that B-1 cell IgM was involved because isotype switching of B-2 cells to produce C-activating IgG isotypes, could not occur as early as day 4. Indeed, B-1 cell deficient CBA/N-xid mice lacked C5a in 2 hr ear extracts, and had impaired CS ear swelling and elaboration of IFN-gamma at 24 hrs. Importantly, adoptive transfer of purified normal peritoneal B-1 cells, or just i.v. injection of Ag-specific IgM monoclonal antibodies in sensitized xid, restored deficient early C5a and late 24 hr ear swelling. These results suggest that early after Ag challenge, specific B-1 cell IgM, produced at distant sites by prior sensitization, forms AgAb complexes that trigger elaboration of C5a, to activate mast cell release of vasoactive TNF alpha and 5-HT to initiate CS, leading to T cell recruitment. We postulate that antibody of various isotypes possibly may lead to local vascular activation to aid in T cell recruitment in a variety of T cell responses, but that very early after immunization, Ag-specific IgM produced by B-1 cells, preferentially serves this important function.
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PMID:B-1 B cell IgM antibody initiates T cell elicitation of contact sensitivity. 1112 74

Despite the great number of studies on mast cell population, at the present time few are the studies regarding the structural aspects of mast cells in human gingiva. In order to identify and characterize gingival mast cells, specimens of healthy human gingival tissue have been studied. Subsequently, in order to test mast cell capability of express TNF-alfa, samples of healthy gingiva with antibody anti-TNF-alfa have been incubated. The results showed that in human gingiva mast cells are numerous and ubiquitarious. These cells exhibit several morphological types of cytoplasmic granules with characteristic subgranular content, varying in shape and density. This allows to divide gingival mast cells into two different subpopulations: either cells containing granules with compact coiled scrolls and/or particles and cells showing granules with scrolls and thin parallel bands. The two ultrastructural aspects observed seem to be correlated to the McT (mast cells containing tryptase) and McTC (mast cells containing tryptase and chymase) described in international literature, differing for ultrastructural aspect, biochemical content and response to secretagogue substances. The positivity of the reaction for TNF-alfa seems indeed to confirm that gingival mast cells are able to secrete sensible amounts of TNF-alfa.
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PMID:Fine structure of healthy human gingival mast cells and their immunological characterization. 1132 9

In this work we analyzed by RT-PCR, the mRNA changes for IL-4, IL-10, TNF and IFN (induced by TSL-1 antigens in a rat mast cell line (HRMC) with mucosal characteristics. The data obtained showed an increase of 65 and 52% in mRNA expression for IL-4 and TNF respectively and a decrease of 59 and 55% in mRNAs for IFN gamma and IL-10. Our results suggest that TSL-1 antigens induce the release from MC of regulatory molecules, such as IL-4 by an IgE independent mechanism. Our data also provides important information related to the ability of MC to participate not only in the effector phase against the infectious agents, but also in the orchestration of the immune response by the host against parasites.
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PMID:Interleukin mRNA changes in mast cells stimulated by TSL-1 antigens. 1148 31

Although the area of research on the role of MCs in innate immunity is relatively new, a number of studies that are reviewed here provide substantial evidence that MCs play a critical role in host immune defense against gram-negative bacteria. The studies show that mast cells have the ability to recognize and engulf bacteria and they release a number of inflammatory mediators including interleukin (IL)-4, IL-6, IL-10, TNF alpha, and leukotrienes in response to bacterial challenge. MC-derived TNF alpha and leukotrienes are shown to be important for bacterial clearance and early recruitment of phagocytic help at the site of infection. Studies directed at elucidating the molecular mechanisms associated with mast cell recognition of bacteria and subsequent events leading to mast cell mediator release revealed that GPI anchored CD48 molecule present on the cell surface of mast cells serves as a receptor for the bacterial adhesion molecule, FimH. The ligation of CD48 receptor by FimH-expressing bacteria results in bacterial uptake into caveolar chambers. This distinct mechanism of bacterial uptake promotes bacterial survival inside the cytosol of the mast cells. Although the exact mechanism(s) of how MC-dependent inflammatory responses are regulated is currently not known, recent studies have shown that complement, CD11 beta/CD18 (Mac-1) and protein tyrosine kinase JAK3, and TLR4 are important for the full expression of MC-dependent innate immunity in mice.
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PMID:Regulation of mast cell-mediated innate immunity during early response to bacterial infection. 1197 23

Mast cells have been shown to produce endothelin-1 (ET-1) and to express ET receptors. Thus, we postulated that ETs modulate mast cell mediator production in an autocrine manner. Rat tissue-cultured mast cells (RCMC-1) were incubated with exogenous ET-1 or ET-3, and beta-hexosaminidase release and TNF, IL-4, IL-10, IL-12, IL-13, macrophage inflammatory protein-1alpha (MIP-1alpha), and nitric oxide (NO) production were investigated. ET-1 and -3 induced the release of beta-hexosaminidase and TNF and of mRNA expression. An antagonist of the ET(B) receptor subtype abrogated ET-stimulated TNF release, although ET(A) and ET(B) receptors have been identified by immunocytochemistry. It is interesting that ET-1 and ET-3 inhibited (25-30%) mRNA expression of Th2-type cytokines (IL-4, IL-10, and IL-13) and increased IL-12 release (39% and 41%, respectively) without affecting MIP-1alpha and NO production. Thus, our data suggest that ETs may play an important role in modulating the cytokine network by regulating Th1/Th2 cytokine production by mast cells.
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PMID:Endothelins regulate mediator production of rat tissue-cultured mucosal mast cells. Up-regulation of Th1 and inhibition of Th2 cytokines. 1199 8

We examined the presence of estrogen receptors (ER) in vascular mast cells and a possible genomic effect of estrogens on the expression of mast cell (MC) mediators such as chymase, TNF alpha, NOS and IL-10, which are known to affect the course of atherosclerosis. Immunocytochemical detection of mast cell tryptase and the co-localization of ERs in MCs from abdominal aortic vessels from 10 fertile woman, 10 postmenopausal women and 15 men was performed. The genomic expression of IL-10, TNF alpha, and NOS was analyzed by RT-PCR and chymase activity by spectrophotometry after 24 h incubation with 17-beta estradiol (0.2-0.5 ng/mL) in rat purified peritoneal MCs. A similar number of MCs were found in both intima and adventitia layers from men, and fertile and postmenopausal women, while ERs were detected only in the arterial walls from fertile women. The mRNA expressions of IL-10 and TNF alpha, as well as chymase activity, were not affected. A moderate increment of NO and both NOS, and a reduction in TNF alpha cytotoxicity was observed after incubating peritoneal MCs with 17-beta estradiol at a concentration of 0.5 ng/mL. Taken together, these results indicate that vascular MCs express ERs. The data demonstrate that estrogens can directly modify vascular MC activity. This is a novel mechanism of synergistic cooperation for the protective role of estrogens in the genesis of atherosclerosis.
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PMID:Estrogen receptors in mast cells from arterial walls. 1205 78


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