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)

The presence of eosinophils in the conjunctival epithelium is indicative of allergies, and detection is currently performed by cotton swab scrapings. Although mast cells are thought to be chemotactic for eosinophils and thus presage their accumulation, the former's use as early indicators of allergy has heretofore been hindered by poor detection methods. The recent development of a special brush now makes it possible to collect many cells with less disturbance of the conjunctival epithelium. In the present study, we have used this brush for conjunctival scraping in 18 patients with vernal and allergic conjunctivitis, and 10 patients serving as controls. The superior and inferior tarsal conjunctiva in both eyes were examined, and the specimens were stained using Hansel's method. Mast cells were observed in at least one of the tarsal conjunctivae in all cases of vernal and allergic conjunctivitis, whereas eosinophils were so observed in only eight cases (44.4%). Neither mast cells nor eosinophils were present in the conjunctivae of the normal group. Although treatment by mast cell stabilizers produced clinical remissions, they induced disappearance of mast cells in only 10 cases (55.6%), whereas in six cases (33.3%) the mast cells increased, and in two cases they were unchanged (11.1%). Six cases (33.3%) each showed disappearance of, increase in, and no change in eosinophils, reflecting even less of a response of these allergic cells to the treatment. The presence of mast cells and eosinophils, as determined by our cytologic method, was found to be correlated with the early detection, but not the clinical severity, of allergic conjunctivitis.
Cornea 1991 Nov
PMID:Detection by brush cytology of mast cells and eosinophils in allergic and vernal conjunctivitis. 178 81

Subconjunctivally injected Onchocerca lienalis microfilariae (Mf) migrate into the guinea pig cornea, resulting, when the microfilariae die, in punctate stromal opacities resembling those of human onchocerciasis. Administration of diethylcarbamazine citrate (DEC-C) following subconjunctival injection of Mf increased the proportion of dead Mf in the cornea, the number of punctate opacities and the extent of peripheral corneal neovascularization. Betamethasone (a synthetic steroid) and lodoxamide tromethamine (an inhibitor of mediator release from mast cells) inhibited the formation of punctate opacities. Chlorpheniramine maleate and cimetidine (H1 and H2 histamine receptor antagonists), given together, did not alter the formation of punctate opacities but inhibited the peripheral corneal neovascularization. These observations suggest that mast cell mediators other than histamine may be of importance in the formation of the corneal punctate opacities.
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PMID:Effect of diethylcarbamazine citrate and anti-inflammatory drugs on experimental onchocercal punctate keratitis. 244 87

Tissue mast cells play a central role in the pathogenesis of allergic eye diseases. In the study reported here the authors investigated whether human corneal epithelial cells and a human epitheloid conjunctival cell line (Chang) can produce an interleukin 3 (IL 3)-like mast cell-activating factor. The activity was detected at a m.w. of 15 and 30 kD, the isoelectric points were located at a pH of 7.85, 7.15 and 6.75. The authors believe that this cytokine, which is produced by epithelial cells of the cornea and conjunctiva, might play an important role in the pathogenesis of allergic ocular diseases.
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PMID:[Corneal epithelial cells and human conjunctival cell line (Chang) produce an interleukin 3-like factor]. 393 69

From in vivo experiments using new methods such as the rabbit cornea, it is now becoming clear that the growth of a capillary involves an ordered sequence of events that includes lysis of the basement membrane of a parent venule, directional migration of capillary endothelial cells toward the angiogenic stimulus, lumen formation, development of branches, and anastomosis of the tip of one tube with another to form a loop. It is also clear that diffusible angiogenic stimuli can be released not only from most solid tumors, but also from at least three non-neoplastic cells. These include activated macrophages, sensitized lymphocytes, and adipocytes. Other normal tissues can also stimulate angiogenesis, but the type of cell giving rise to the angiogenic stimulus is unknown, and the period of angiogenic stimulation is brief. With the recent ability to clone capillary endothelial cells and to carry them in long-term culture, it has been possible to further delineate the mechanism of capillary growth. In vitro studies have shown that the mast cell seems to behave as a helper cell for capillary endothelial cells, in some way speeding up their rate of directional migration. At this writing, heparin appears to be the principal mast cell factor responsible for this effect on capillary endothelial cells. One theoretical possibility is that mast cells may prepare the matrix, perhaps by slow release of heparin, so that capillary sprouts can more easily move through it toward their angiogenic target. While the study of angiogenesis as a phenomenon is still in an early phase, it has become possible, by using a combination of in vitro and in vivo techniques, to more thoroughly understand the initiation and control of capillary growth.
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PMID:Angiogenesis: initiation and control. 618 1

Tryptase is useful as a specific and accurate indicator of mast cell activation, whereas histamine, a mast cell's major mediator, also exists in basophils. The aim of this study is to investigate histamine and tryptase levels in allergic conjunctiva. We measured histamine and tryptase levels in conjunctival epithelial cell suspension of children with allergic conjunctivitis (AC) and vernal kerato-conjunctivitis (VKC), and controls, and we evaluated correlations with clinical observations. Both the histamine and tryptase levels in VKC were significantly higher than controls (p < 0.05, p < 0.01), and histamine levels in VKC was also greater than AC (p < 0.05). The histamine/tryptase (H/T) ratios were 0.03 +/- 0.04 in AC, 0.08 +/- 0.09 in VKC and 0.006 +/- 0.006 in controls. The H/T ratios in VKC were significantly higher than controls (p < 0.05) and AC (p < 0.05), and were also found to correlate with the superficial punctate keratopathy (SPK) score (r2 = 0.89). Analyzing the histamine and tryptase levels in conjunctival epithelium may be useful in evaluating the allergic ocular surface, especially in the cases with SPK, where the increase in the histamine levels is not accompanied by an increase in tryptase levels. This suggests an important role for inflammatory cells such as basophils infiltrating into the conjunctival epithelium in allergic reactions.
Cornea 1994 Jul
PMID:Histamine and tryptase levels in allergic conjunctivitis and vernal keratoconjunctivitis. 792 35

The term ocular allergy encompasses a group of diseases in which there is a high frequency of atopy, ocular itching, stringy discharge and a papillary conjunctival reaction. Conditions confined to the lids and conjunctiva (e.g. seasonal allergic conjunctivitis) have a good prognosis but those involving the cornea may result in visual impairment (e.g. atopic keratoconjunctivitis). Mast cell and eosinophil mechanisms are important in al the ocular allergies, but T cell inflammation is prominent only in vernal keratoconjunctivitis, atopic keratoconjunctivitis and giant papillary conjunctivitis. Therapy involves the use of antigen avoidance (where possible), nonspecific medical therapy (e.g. cold compresses, artificial tears), specific medical therapy and, in certain situations, immunotherapy and surgery. Topical antihistamines (often in combination with a vasoconstrictor) and oral antihistamines are widely used in perennial and seasonal conjunctivitis. Levocabastine is a new preparation which is more rapid and potent. Mast cell inhibitors [e.g. sodium cromoglycate (cromolyn sodium)] have a proven track record as safe and effective therapy for all ocular allergic diseases and the newer, more potent nedocromil and lodoxamide are now available. Topical steroids are only indicated in sight-threatening disease due to their serious adverse effects and other therapy should be continued to minimise the dose required. There is a lack of intermediate potency and high potency but safe topical preparations. A number of future possibilities exist, some of which have been partially explored. Cyclo-oxygenase inhibitors have proved of limited use, but inhibitors of lipoxygenase and kinin pathways are awaited. Although results with HEPP have been disappointing, other modulators of mast cell function (e.g. picumast, beta-agonists and phosphodiesterase inhibitors) may prove useful in the future. So far, results with topical cyclosporin in serious disease are very encouraging. Future developments in the manipulation of eosinophilic products, cytokines and adhesion molecules may also be relevant. However, the current situation for those with serious ocular allergy remains a disturbing dependence upon topical steroids, with all the attendant risks.
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PMID:Therapeutic options in ocular allergic disease. 852 55

Recent findings have helped to explain the fate of cholesterol entering the arterial wall. LDL can undergo both fusion and aggregation. These changes may cause increased retention of LDL in lesion connective tissue matrix and LDL uptake by macrophages. In the cornea, apparent fusion of LDL occurs in the absence of macrophages. Mast cells may be important in LDL fusion, as mast cell-derived proteases can induce fusion of LDL through proteolysis of apolipoprotein B. LDL in arterial wall atherosclerotic lesions was found to be sialic acid-poor and ceramide-enriched. These chemical changes promote LDL aggregation. Processes that may function to remove cholesterol from the arterial wall have been reported. Macrophage-produced apolipoprotein E can mediate macrophage cholesterol efflux and macrophages can convert cholesterol to 27-oxygenated products that macrophages excrete. Alternately, another oxygenated sterol, 7-ketocholesterol, impairs macrophage cholesterol efflux. In addition, mast-cell derived chymase proteolyses HDL and reduces its capacity to stimulate cholesterol efflux.
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PMID:The fate of lipoprotein cholesterol entering the arterial wall. 933 47

The aim of this study was morphological analysis of corneal disks and conjunctival biopsy specimens in order to disclose the mechanisms of development of epithelial-endothelial dystrophy (EED) and validating pathogenetically-based therapy. Twenty-five patients were observed, 11 of these with implanted intraocular lenses of different localization. EED developed for 1 to 5 years. Sixteen biopsy specimens of the conjunctiva and 21 corneal disks were examined. The composition and index of inflammatory infiltrate, status and compactness of conjunctival vessels, severity of fibrosis, and mast cell degranulation were assessed. Mast cells play a positive role at the initial stages of tissue and cellular response to injury by regulating the formation of extracellular matrix and fibroblast proliferation. At the reparative stages of immune inflammation of the conjunctiva, mast cells are virtually the only cell population; fibrosis and sclerosis develop when the capillary bed is reduced, causing ischemic involvement of the anterior segment of the eye and dystrophic processes in the cornea. A differentiated approach to treatment of EED at the stages of immune inflammation and fibrosis is emphasized.
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PMID:[Morphogenesis of corneal epithelial-endothelial dystrophy (a comparative morphological analysis of corneal disks and biopsy specimens of the conjunctiva)]. 962 23

The present study investigates the effect of the somatostatin analogue octreotide acetate (SMS 201-995) on experimental angiogenesis in vitro and in vivo. Octreotide reduced the proliferation of human HUV-EC-C endothelial cells (mean, -45.8% versus controls at 10(-9) M; P < 0.05) as well as the density of the vascular network of the chick chorioallantoic membrane (mean, -35.7% versus controls at 50 microgram; P < 0.05). Furthermore, octreotide significantly inhibited chick chorioallantoic membrane neovascularization by the human MCF-10Aint-2 mammary cells secreting the angiogenic protein FGF-3. The proliferation of endothelial and smooth muscle cells from rat aorta explants on fibronectin was reduced by octreotide 10(-8) M (mean, -32.6% versus controls; P < 0.05), and a similar effect was produced on cells sprouting from explants cultured in fibrin (mean, -52.9% versus controls; P < 0.05). Topical administration of octreotide 10 microgram/day for 6 days inhibited rat cornea neovascularization induced by AgNO3/KNO3 (mean, -50.6% versus controls; P < 0.05). Octreotide 40 microgram/day i.p was tested on angiogenesis in rat mesentery obtained by i.p. injections of compound 48/80, a mast cell degranulating agent, or conditioned medium from MCF-10Aint-2 cells and was able to reduce the extent of neovascularization (mean, -45.6 and -64.1%, respectively, versus controls; P < 0.05). These data provide evidence that octreotide is an inhibitor of experimental angiogenesis in vitro and in vivo.
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PMID:Inhibition of experimental angiogenesis by the somatostatin analogue octreotide acetate (SMS 201-995). 981 82

Ocular allergic disorders can be a component of systemic or local allergies. The importance of ocular allergy results from its incidence rather than from its severity, however, some of them are vision-threatening. The majority of ocular allergies affect the conjunctiva, eyelids and sometimes cornea that is exposed to the environment and is the place of interaction between allergens and immunocompetent cells. Different types of allergic disorders in the eye may have similar signs and symptoms, but each has its own pathognomonic characteristics, which help to diagnose, differentiate and choose the most suitable therapy. Ocular allergic diseases are classified into six categories: SAC, PAC, VKC, AKC, GPC and ConBC. In 2001 EAACI suggested new classification, also of allergic conjunctivitis, into IgE-mediated and non-IgE-mediated conjunctivitis. IgE-mediated conjunctivitis may be divided into intermittent and persistent conjunctivitis. Persistent allergic conjunctivitis is classified into vernal and atopic keratoconjunctivitis. Conjunctivitis contact allergy is a non-IgE form of allergic conjunctivitis. Currently available medications provide safe and effective management of most cases of ocular allergy. Drugs used in the treatment of ocular allergic disorders include mast cell stabilizers, antihistamines, steroids, NSAID's, artificial tears and others.
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PMID:[Clinical picture, diagnosis and therapy of allergic eye diseases]. 1452 17


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