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)

A technique utilizing Pregnant Mare's Serum Gonadotropin and Human Chorionic Gonadotropin treatment of hens (Gallus domesticus), followed by manual ovulation of the excised follicles, was developed to obtain a large number of mature ova. The intact ova were used to test whether acrosin, partially purified from the spermatozoa of the cock (Gallus domesticus), partially purified rabbit testicular acrosin and commercial preparations of several hydrolytic enzymes could dissolve the inner vitelline membrane. Enzymes were applied to pieces of filter paper placed on the ovum. Cock acrosin and endopeptidases such as trypsin, chymotrypsin, collagenase and elastase hydrolyzed the membrane whereas exopeptidases such as leucine aminopeptidase and carboxypeptidase A did not. Phospholipase A, sulfatase, hyaluronidase, beta-glucuronidase and rabbit testicular acrosin also failed to hydrolyze the membrane. Cock acrosin hydrolysis of the ovum surface was inhibited by soybean trypsin inhibitor. The surface of the ovum over the germinal disc region was hydrolyzed more quickly by cock acrosin than the surface over other regions of the ovum. Acrosin from cock sperm caused the release of trichloroacetic acid soluble material absorbing at 280 nm from sonicated preparations of inner vitelline membranes. Hydrolysis was greatest at pH 8.0 and was inhibited by soybean trypsin inhibitor.
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PMID:Hydrolysis of the hen egg vitelline membrane by cock sperm acrosin and other enzymes. 0 Apr 54

Using the indirect immunofluorescence technique, the basic kallikrein-trypsin inhibitor of bovine organs, Trasylol, could be localized in tissue mast cells of bovine lung, liver, pancreas and parotid gland. Identification of cells exhibiting specific fluorescence as tissue mast cells was achieved by combined light and electron microscopic diagnosis of bovine liver tissue sections. The presence of Trasylol in mast cells explains the widespread distribution of this inhibitor in functionally totally different organs or tissues of the bovine organism, as determined earlier by biochemical means. Identification of Trasylol as a mast cell constituent will facilitate the search for the biological function of this inhibitory protein in connection with a unique and highly specialized cell population.
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PMID:Immunofluorescence studies indicate that the basic trypsin-kallikrein-inhibitor of bovine organs (Trasylol) originates from mast cells. 37 18

Cell-free particulate preparations derived from sonicated, purified rat peritoneal mast cells can be radiolabeled with IgE. The IgE concentration-dependence and the kinetics of the binding reaction at pH 6.6 were very similar to those observed with intact mast cells. The number of IgE molecules bound per mast cell equivalent at saturation varied somewhat from one particulate preparation to the next and, on average, was about 50% of the binding capacity of the intact cells. Incubation of intact mast cells or of particulate fractions with low concentrations of IgE in serum-free media resulted in a decrease in the amount of bindable IgE which remained in the supernatants in excess over the amount of IgE which was bound to the cells. Specific binding of IgE to both particles and to intact cells at limiting IgE concentrations was stimulated up to approximately twofold by a variety of antibiotic, synthetic or high molecular weight (protein) protease inhibitors of which soybean trypsin inhibitor and p-nitrophenyl-p'-guanidinobenzoate were the most active. These substances also markedly protected the IgE, leaving more of it bindable to rat basophil leukemic cells in a second incubation. Binding to particulate fractions also occurred at pH 4.8 when bovine serum albumin was added to the incubations. The results are consistent with the view that normal peritoneal mast cells have a membrane-bound protease which has high selectivity for IgE.
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PMID:On the nature of the presumed receptor for IgE on mast cells. V. Enhanced binding of 125I-labeled IgE to cell-free particulate fractions in the presence of protease inhibitors. 61 23

Axon reflex vasodilation following injury to the skin of the pinna of the ear was studied in rats by a thermometric method. Post-traumatic vaso-dilatation did not occur in animals treated with tyrosine ethyl ester, an inhibitor of chymotrypsin. Vasodilatation was not affected by treatment of the rats with chlorpheniramine (antihistamine) or cyproheptadine (antihistamine and anti-serotinin) or with aprotinin, soybean trypsin inhibitor, epsilon-aminocaproic acid or tosyl arginine methyl ester (inhibitors of trypsin and of some other proteinases). Taken in conjunction with the results of other investigations, these findings indicate that in the skin of the rat: (a) histamine and serotinin are not essential for the initiation of axon reflexes, and (b) the chymotrypsin-like proteinase of mast cell granules, released as the result of antidromic activity in sensory axons, may act as a kininogenase and be responsible for causing dilatation of arterioles at the efferent limb of the axon reflex.
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PMID:Evidence for the involvement of vasoactive constitutents of mast cells in axon reflex vasodilatation in the skin of the rat. 125 6

Bovine tryptase, a mast cell trypsin-like protease, was isolated from liver capsula and from mast cells obtained from the same tissue. The purification procedure which leads to an increase in tryptase activity of 850 fold, involves high salt extraction, hydrophobic interaction chromatography on octyl-Sepharose and affinity chromatography on heparin-Sepharose. The enzyme is oligomeric, with an apparent M(r) of 360,000 +/- 40,000 (as obtained by gel filtration in high salt). The constituent subunits with M(r) 39,000 and 41,000 Da are both labeled with [3H] diisopropyl fluorophosphate and cross-react with anti-rat tryptase immunoglobulins. Only a single N-terminal sequence was found, identical to that of human, dog and rat tryptases. Tripeptide fluorogenic substrates with basic residues in P1 and P2 positions are preferentially hydrolyzed by this enzyme, suggesting a possible processing role as proposed for other tryptases. Bovine tryptase activity is inhibited by NaCl and is insensitive to high molecular weight inhibitors, such as alpha 1 antitrypsin and soybean trypsin inhibitor, as for human and dog tryptases. However it is inhibited by low molecular weight serine protease inhibitors and, similarly to rat tryptase, by the bovine pancreatic trypsin inhibitor (BPTI or aprotinin), in a pH dependent fashion.
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PMID:Bovine tryptase: purification and characterization. 151 79

Calcitonin gene-related peptide (CGRP) is localized in and released from sensory nerves. It is a potent and long acting vasodilator which has been suggested to play a role in the control of blood flow. Using HPLC and trichloroacetic acid precipitation techniques, we have examined the ability of human mast cell lysates and a purified preparation of mast cell tryptase to degrade CGRP. We found that CGRP is effectively cleaved by tryptase (Km = 6.8 x 10(-6) mol/L at 37 degrees). Enzymatic activity was inhibited by antipain, leupeptin, N-alpha-p-tosyl-L-lysine chloromethyl ketone, benzamidine or aprotinin, but not by soybean trypsin inhibitor or N-tosyl-L-phenylalanine chloromethyl ketone. The degradation of CGRP by lysates of purified skin mast cells showed a similar pattern of inhibition suggesting that tryptase may be the major enzyme involved. The activity of tryptase was not affected by the presence of heparin. Incubation of CGRP with tryptase resulted in a loss of its vasodilator activity as observed by intravital microscopy of the hamster cheek pouch microvasculature. CGRP preincubated with tryptase failed to relax arterioles when added topically. It is suggested that the catalysis of CGRP by tryptase could represent an important means by which the activity of this neuropeptide is regulated in vivo.
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PMID:Human mast cell tryptase attenuates the vasodilator activity of calcitonin gene-related peptide. 156 77

Incubation of radiolabeled human C3a with rat peritoneal mast cells resulted in high levels of uptake and extensive degradation of the ligand. Both cell-bound and free radiolabeled human C3a underwent extensive degradation by rat mast cells even at 0 degrees C. We examined several protease inhibitors for their ability to prevent degradation of radiolabeled human C3a by the rat mast cells. The inhibitors PMSF, chymostatin, and soybean trypsin inhibitor were most effective in preventing radiolabeled human C3a degradation. Degradation of the cell-bound ligand was totally inhibited only by PMSF. These compounds are effective inhibitors of a chymotrypsin-like enzyme (chymase) extracted from rat mast cells. Chemical cross-linking of radiolabeled human C3a to surface components on the rat mast cells, in the presence of PMSF, revealed one major and two minor bands. The mast cell component in both the major and minor bands proved to be chymase-associated based on a direct comparison with purified chymase isolated from rat mast cells. However, neither antichymase antibody nor chymase inhibitors influenced the degranulating activity of C3a on rat mast cells that occur independently of the C3a-chymase interactions. We conclude that there are neither specific C3a-binding sites on rat mast cells nor specific receptors whose occupancy leads to cellular activation. Although human C3ades Arg is inactive on guinea pig ileal and lung tissue, it binds to and induces degranulation of rat mast cells, as well as enhances vascular permeability in rat skin, at concentrations nearly identical to that of intact C3a. The fact that both C3a and C3ades Arg stimulated mast cell activation, at concentrations in excess of 10(-6) M, argues against specific binding sites for the anaphylatoxin on rat mast cells. It is proposed that the cationic C3a molecule activates rat mast cells in a secretory and nonlytic manner by a nonspecific mechanism similar to that of other polybasic compounds.
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PMID:Anaphylatoxin binding and degradation by rat peritoneal mast cells. Mechanisms of degranulation and control. 169 12

The neutral protease tryptase has been isolated from a human mast cell line, HMC-1. The HMC-1 line was established from the peripheral blood of a patient with mast cell leukemia and maintained as continuously proliferating clones in vitro and as solid mast cell tumors in nude mice. HMC-1-derived tryptase was purified by sequential chromatography on Dowex 1, DEAE 5 PW, and heparin-agarose. Purified tryptase has an apparent molecular weight of 150,000, as determined by molecular sieve HPLC, but migrates as a doublet of bands of 32/35,000 on SDS-PAGE gels. Maximal enzymatic activity was observed at pH 8.5. Cleavage of tosyl-L-arginine methyl ester by purified tryptase was inhibited by dansyl-L-glutamyl-glycyl-L-arginine chloromethyl ketone 2 HCl, HgCl2, tosyl-L-lysine chloromethyl ketone, leupeptin, and PMSF but not by benzamidine, aprotinin, tosyl-L-phenyl-alanine chloromethyl ketone, soybean trypsin inhibitor, human plasma, ovomucoid inhibitor, or lima bean trypsin inhibitor. Microsequencing of purified tryptase yielded an amino terminal sequence that was identical to that previously reported for human pituitary-derived tryptase.
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PMID:Purification of tryptase from a human mast cell line. 211 May 91

Microproteins with proteinase inhibitory activity, 28 to 30 amino acids long, with 3 disulfide bridges have been isolated from Ecballium elaterium seeds. A peptide (EETI II) was isolated and behaved as a powerful trypsin inhibitor (Kd = 10(-11) to 10(-12) M). It was sequenced, chemically synthesized and the 3-D structure determined by 2-D 1H NMR. The information gained in the process enabled us to synthesize modified derivatives with inhibitory activity towards pancreatic elastase, chymotrypsin and human leucocyte elastase (Kd = 10(-7) to 10(-9) respectively). The most striking characteristic that appeared during the synthetic approach was the unfailing ability of the 28 amino acid peptides to refold and correctly close the 3 disulfide bridges, giving in each case an active compound. These disulfide bridges are assembled in a particular knotted structure, shared by few other bioactive peptides and called the 'knottin' structure. Molecular modeling of the peptide and a comparison with the other active molecules with similar topology allowed the synthesis of a chimaeric peptide, bearing 1 active site against a seryl-protease (trypsin), and 1 against a metallo-protease (carboxypeptidase A). The bis-headed peptide was able to inhibit both enzymes separately and concomitantly.
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PMID:Molecular recognition between serine proteases and new bioactive microproteins with a knotted structure. 212 46

Dinitrophenyl (DNP) derivatives of various molecular weights were tested for their ability to elicit ocular anaphylaxis after topical application to the eye of immunized animals. Adult male Sprague-Dawley rats were immunized by intraperitoneal injection of DNP-Ascaris suum extracts and alum and were then skin-tested with DNP-bovine serum albumin on day 13 post-immunization to assess their sensitivity to the DNP hapten. On day 14, animals were challenged topically with DNP derivatives in one eye; PBS was applied to the contralateral, control eye. Animals were evaluated clinically, and ocular tissues were processed for histologic evaluation. The compounds used for topical ocular challenge included the DNP derivative of egg albumin (MW 43,500 D), soybean trypsin inhibitor (MW 20,080 D), insulin (MW 5733 D), B-chain insulin (MW 3496 D), and lysine (MW 478 D). Only di-DNP-lysine elicited clinical signs of redness, edema, and tearing and histologic evidence of mast cell degranulation. None of the other compounds, tested in solutions of either equal numbers of milligram per milliliter or equimolar concentrations, elicited ocular anaphylaxis after topical application. A compound of low molecular weight, less than 3496, is needed to elicit ocular anaphylaxis when applied topically.
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PMID:Penetrating the conjunctival barrier. The role of molecular weight. 230 28


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