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 purpose of this study was to compare, for the first time, antigen-induced histamine release from the lung in the same natively allergic dogs both in vitro and in vivo. In six dogs, maximal antigen-induced histamine release from the lung correlated closely in vitro and in vivo (r = 0.94), although it varied widely between dogs (0% to 75.5% of total tissue histamine content); similarly, the antigen concentration to produce 50% of maximal histamine release varied sixfold between dogs (40 micrograms/ml to 250 micrograms/ml). In each of five other dogs, terbutaline sulfate administered intravenously caused a dose-dependent inhibition of antigen-induced histamine release from lung fragments in vitro: the maximal inhibition produced by 1 mg/kg was 60 +/- 4.5% (mean +/- SEM). In these same dogs, 10(-5)M terbutaline incubated with lung fragments in vitro caused inhibition of antigen-induced histamine release comparable to 1 mg/kg terbutaline in vivo. Increasing the dose of terbutaline in vitro produced maximal inhibition at 10(-4)M with no greater effect of the drug at 10(-3)M (71.4 +/- 3.8% inhibition). In both experimental situations propranolol caused a dose-dependent inhibition of beta-adrenergic modulation of Ascaris-induced release of histamine. This result supports the conclusion that terbutaline produced its effects by actions mediated by beta-adrenergic receptors on pulmonary mast cells. This experimental approach provides a suitable preparation in which to estimate the effective dose of agonists that modulate antigen-induced mast cell function in vivo.
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PMID:Immunologic release of histamine from dog lung: comparison of in vivo and in vitro responses in the same animal. 620 22

Tryptase, the dominant neutral protease of human pulmonary mast cell secretory granules, has the capacity in vitro to generate C3a anaphylatoxin from purified human C3. Only the alpha-chain of C3 is cleaved, and major fragments with apparent m.w. of 105,000, 39,500, 34,000, 29,000, and 9000 are detected by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis under reducing conditions. Fragments of 34,000 and 9000 m.w. are detected without reduction. A portion of the 9000 m.w. protein corresponds to C3a by virtue of its co-migration in SDS polyacrylamide gels with purified C3a and with trypsin-generated C3a, by its detection in a radioimmunoassay for C3a, and by its contractile activity on the guinea pig ileum bioassay. In the presence of heparin, another component of the mast cell secretory granule, the rate of appearance and the distribution of C3 cleavage fragments as assessed in SDS polyacrylamide gels are not appreciably changed with the exception that no C3a material can be detected in the SDS polyacrylamide gels or by radioimmunoassay and bioassay of the unresolved reaction mixture. Enhanced catabolism of authentic C3a by tryptase occurs in the presence of heparin and by analogy when C3a is generated from C3 by tryptase in the presence of heparin. Whereas tryptase secreted by activated human mast cells may generate C3a, a potentially important additional mediator of immediate hypersensitivity events, the concomitant release of heparin may serve to down-regulate C3a irrespective of its mechanism of generation.
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PMID:Generation of C3a anaphylatoxin from human C3 by human mast cell tryptase. 633 18

Tryptase, the major neutral protease of human pulmonary mast cell secretory granules, rapidly inactivates human high m.w. kininogen (HMWK) in vitro. HMWK (5600 nM) lost 50% of its capacity to release kinin in response to kallikrein after a 5-min incubation with tryptase (31 nM), even though kinin activity was neither generated nor, when bradykinin was incubated with tryptase, destroyed by tryptase. The procoagulant activity of HMWK (51 nM) and the purified procoagulant chain (40 nM) that is derived from HMWK were each 72% inactivated after 7 min of incubation with tryptase (0.04 nM and 0.02 nM, respectively). Human urinary and pancreatic kallikrein did not inactivate this procoagulant activity under conditions in which kinin generation occurs. Complete cleavage of native single-chain HMWK by tryptase occurred in less than 10 min as analyzed by electrophoresis in sodium dodecyl sulfate polyacrylamide slab gels. The major products formed during the initial 2 min were proteins of 100,000 and 95,000 apparent m.w., and by 10 to 30 min were fragments of 74,000 and 67,000 apparent m.w. Reduction of these cleavage products yielded two major fragments of 67,000 and 66,000 apparent m.w. that were both present by 0.17 min. The presence of lower m.w. products, thought to be primarily from the carboxy-terminal procoagulant region of HMWK, were also detected with and without reduction. The capacity of tryptase to inactivate HMWK is consistent with the ability of other mast cell-derived mediators, such as heparin proteoglycan and prostaglandin D2, to suppress blood coagulation and thrombosis, and may play an important role in the biology of mast cell-dependent events in vivo.
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PMID:Inactivation of human high molecular weight kininogen by human mast cell tryptase. 633 26

The orientation of the lactose:H+ carrier of Escherichia coli in various preparations of native and reconstituted vesicles is determined with two impermeant, macromolecular probes: antibodies directed against the C-terminal decapeptide of the carrier and carboxypeptidase A (EC 3.4.17.1). Two methods are employed. Method I is based upon the digestion of all accessible and, therefore, presumably external, C termini of the carrier with carboxypeptidase A and detection of the remaining, internal C termini with 125I-labelled anti-(C-terminus) antibody after electrophoresis of the carrier in the presence of sodium dodecyl sulfate and transfer to nitrocellulose filters. Method II is based upon the binding of 125I-labelled anti-(C-terminus) antibody to the external C termini of the carrier in vesicles and the subsequent isolation of bound antibody by centrifugation. The labelled antibodies are calibrated using a preparation of inside-out vesicles prepared by high-pressure lysis of strain T206. The carrier content is determined by substrate binding. Because the C terminus of the carrier is known to reside on the cytoplasmic side of the membrane, these methods can also be used to determine the sidedness of various preparations of membrane vesicles. Spheroplasts are confirmed to contain carrier molecules of a single orientation, corresponding to that in right-side-out vesicles. In contrast, in purified cytoplasmic membrane vesicles and in crude membrane preparations obtained by sonication or by high-pressure lysis, 96% of the C termini are accessible to carboxypeptidase A, even after repeated sonication. This implies that nearly all carrier molecules in these preparations possess an orientation opposite to that in the cell or in right-side-out vesicles. In proteoliposomes containing carrier reconstituted or purified and reconstituted by two different methods, only 48% of the carrier molecules are oriented in the same way as in the cell. Subjecting such proteoliposomes to cycles of freezing and thawing or to sonication results in a reshuffling of carrier molecules between the inside-out and right-side-out populations while maintaining 41% in the right-side-out orientation. Digestion of the C terminus of the carrier with carboxypeptidase A does not alter either galactoside binding or countertransport. Thus carrier molecules of the inside-out orientation cannot be selectively inactivated. Additionally, an antiserum directed against the purified carrier is demonstrated to contain nearly exclusively anti-(C-terminus) antibodies, which can, in principle, be used in Method I.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Sidedness of native membrane vesicles of Escherichia coli and orientation of the reconstituted lactose: H+ carrier. 637 37

Four low-molecular-mass polypeptides were isolated and purified from chromatophore membranes of Rhodopseudomonas sphaeroides blue-green mutant R-26.1 by a combination of gel filtration and ion-exchange chromatography in organic solvents. On dodecyl sulfate polyacrylamide gels, the purified polypeptides comigrate with bands LH-1, LH-2 and LH-3 known to be related to the antenna-pigment-protein complexes. The complete primary structures were elucidated by automated Edman degradation of the intact polypeptides and of overlapping C-terminal fragments obtained after chemical cleavage at tryptophan and methionine residues. The C-termini were verified by hydrazinolysis and, in one case where an overlapping C-terminal fragment could not be obtained, by digestion with carboxypeptidase A. The four polypeptides show a tripartite structure: i.e. a polar N-terminal region is separated from a polar C-terminal region by a segment of about 21 predominantly hydrophobic amino-acid residues. All hydrophobic segments contain a characteristic conservative histidine residue. The C-terminal region is reduced to only a few amino acids in the two polypeptides which together form band LH-3, i.e. LH-3A and LH-3B. Their extended N-terminal region is rich in charged residues and contains an additional conserved histidine residue close to the beginning of the hydrophobic segment. These properties place LH-3A and LH-3B into subgroup (beta-polypeptides: B 870-beta and B 850-beta, respectively). LH-1 and LH-2 appear to form another subgroup (alpha-polypeptides: B 870-alpha and B 850-alpha, respectively) as suggested during a search for conservative elements within their sequences (structural basis for classification). N-Terminal analyses carried out with intact antenna-pigment-protein complexes revealed the following: (i) LH-1 and LH-3 are associated with the B 870 complex in Rp. sphaeroides 24.1 (wild type), (ii) the same polypeptides are almost exclusively present in chromatophore membranes of Rp. sphaeroides R-26, a blue-green mutant which absorbs at 870 nm, (iii) LH-2 and LH-3B are the constituent polypeptides of the B 800-850 complex of Rp. sphaeroides 2.4.1 and of the spectrally altered B 850 complex isolated from the blue-green mutant R-26.1 which absorbs at 860 nm. This mutant contains LH-2 and LH-3B along with LH-1 and LH-3A and apparently is able to form both types of antenna complexes.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The light-harvesting polypeptides of Rhodopseudomonas sphaeroides R-26.1. I. Isolation, purification and sequence analyses. 638 9

To explore the effect of mast cell products on lymphocytes, the blastogenic response of lymphocytes to mast cell granules in the absence and presence of mitogens was determined. Membrane-free granules (MFG) and dialyzed, washed histamine-free granules (DWG) in the absence of mitogens did not induce significant blastogenesis in peripheral blood mononuclear cells (PBMC) before or after partial depletion of macrophages (5 to 10%). In contrast, concanavalin A- (Con A) (5 micrograms/ml), pokeweed mitogen- (PWM) (1/200 dilution), tetanus toxoid-, and Candida-, but not phytohemagglutinin-, induced blastogenesis in macrophage-depleted PBMC were inhibited by both MFG and DWG. Fractionation of solubilized DWG by anion exchange Dowex chromatography into protein- and heparin-rich fractions revealed the inhibitory activity resided in the heparin-containing fractions. The ability of commercial porcine heparin glycosaminoglycan as well as native rat heparin proteoglycan to inhibit lectin-induced blastogenesis in a dose-response fashion confirmed the previous data with the use of fractionated DWG. Histamine and commercial porcine heparin glycosaminoglycan were not additive in inhibiting lectin-induced lymphocyte blastogenesis. The inhibitory effect of heparin on Con A-induced blastogenesis could be overcome by adding excess Con A to macrophage-depleted mononuclear cell preparations and could be reproduced by using over-sulfated chondroitin 6-sulfate. This is the first examination of the ability of mast cell granules to influence lymphocyte function and the first demonstration of the ability of native heparin proteoglycan to modulate lymphocyte blastogenesis.
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PMID:Analysis of the effect of mast cell granules on lymphocyte blastogenesis in the absence and presence of mitogens: identification of heparin as a granule-associated suppressor factor. 641 84

Proteoglycans from three cloned, granulated lymphocyte cell lines with natural killer (NK) function (NKB61A2, HY-3, H-1) and one mast cell line (PT-18) were labeled with [35S]sulfate. [35S]proteoglycans were extracted in 1 M NaCl with protease inhibitors to preserve their native structure and were separated from unincorporated [35S]sulfate by Sephadex G-25 chromatography. [35S]proteoglycans from all four cell lines were chromatographed over Sepharose 4B and were found to have a similar range of m.w. The [35S]glycosaminoglycans from each cell line were then separated from parent proteoglycans by treatment with 0.5 M NaOH. The [35S]glycosaminoglycans from the three lymphocyte cell lines exhibited a similar m.w. as assessed by Sepharose 4B gel filtration, whereas the [35S]glycosaminoglycans from the mast cell line chromatographed as a smaller m.w. molecule. [35S )glycosaminoglycan charge characteristics were evaluated with DEAE C1-6B ion exchange chromatography. The consistency of the elution patterns was determined by using [35S]glycosaminoglycans obtained from radiolabelings of each cell line separated by 6 mo in culture. Each NK lymphocyte cell line reproducibly produced two distinct [35S]glycosaminoglycan chains that eluted in two regions well before the commercial heparin marker. The proportions of each chain were dependent upon the specific cell line. The mast cell line produced a single [35S]glycosaminoglycan chain, which eluted overlapping the internal commercial heparin marker, consistent with its higher charge characteristics. [35S]glycosaminoglycans from all cell lines were identified as chondroitin sulfates with the use of specific polysaccharidases. The NK lymphocyte glycosaminoglycans contained chondroitin 4-sulfate disaccharides. The mast cell glycosaminoglycans contained oversulfated disaccharides and chondroitin 4-sulfate disaccharides. Thus, each granulated NK lymphocyte cell line produced chondroitin sulfate glycosaminoglycans that were characteristic of that cell line and of different composition and less charge than those produced by cultured mast cells. These findings demonstrate that glycosaminoglycan profiles are useful biochemical markers in the characterization of diverse granulated cell lines including NK lymphocytes and mast cells.
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PMID:Glycosaminoglycan profiles in cloned granulated lymphocytes with natural killer function and in cultured mast cells: their potential use as biochemical markers. 642 30

We compared the relative capacities of two over-sulfated glycosaminoglycans, heparin and chondroitin sulfate E, to alter the function of native properdin (nP) and activated properdin (aP) in the formation and stabilization of the amplification C3 convertase (C3b,Bb). Heparin was more active on a weight basis than chondroitin sulfate E in inhibiting the formation of C3b,Bb without or with nP, but had no influence on the decay of a pre-formed convertase, either unstabilized or stabilized with nP or aP. In contrast, chondroitin sulfate E was over 10-fold more active than heparin in preventing the formation of C3b,Bb in the presence of aP, and gave dose-related acceleration of decay of pre-formed C3b,Bb,aP but not of unstabilized or nP-stabilized pre-formed convertase. The inhibitory effect of both glycosaminoglycans on the formation of C3b,Bb in the presence of nP or aP was less when the number of C3b sites per target cell was increased. The preferential action of chondroitin sulfate E on the function of aP during the formation and decay of C3b,Bb,aP as compared to C3b,Bb,nP implies functional differences in the two forms of P even when they have been incorporated into C3b,Bb. The equal potency, when adjusted for uronic acid content, of chondroitin sulfate E proteoglycan isolated from the T cell-dependent, bone marrow-derived murine mast cell and of chondroitin sulfate E glycosaminoglycan from squid reveals that the linkage of the glycosaminoglycan to a peptide core does not diminish its regulatory action on the alternative complement pathway.
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PMID:Inhibition of the function of activated properdin by squid chondroitin sulfate E glycosaminoglycan and murine bone marrow-derived mast cell chondroitin sulfate E proteoglycan. 642 31

Human lung tryptase, a mast cell-derived trypsin-like serine protease, has been isolated from whole human lung tissue obtained at autopsy. Increased yields from this purification process have allowed extensive characterization of the enzyme. One of the critical steps in the purification scheme is the use of a linear heparin gradient to elute active material from cellulose phosphate. Gel filtration studies in 1.0 M NaCl yielded an apparent Mr = 135,000, and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated the presence of two active species with apparent Mr = 30,900 and 31,600. Enzymatic activity was sensitive to NaCl concentrations above 0.05 M and was only 50% in 0.15 M NaCl, decreasing to 18% in 0.6 M NaCl. The effects of synthetic and natural inhibitors have also been studied, confirming the enzyme's trypsin-like characteristics and demonstrating that naturally occurring serum inhibitors are incapable of diminishing its activity. A complete amino acid analysis showed a high tryptophan content. Lastly, antisera to human lung tryptase have been generated, and the immunological identity of active fractions has been investigated as well as the localization of the enzyme to the mast cell granule by immunohistochemical staining.
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PMID:Human lung tryptase. Purification and characterization. 643 91

A high-performance liquid chromatography method for analyzing disaccharides derived from chondroitin sulfate glycosaminoglycans has been developed which employs a Whatman Partisil-10 PAC amino-cyano column and an acetonitrile/methanol/ammonium acetate solvent to resolve disulfated, monosulfated, and unsulfated disaccharides in a chromatographic run of less than 20 min. The single known trisulfated chrondroitin disaccharide can be eluted in an alternate solvent system containing the same mobile phase components in different proportions. Disaccharides were prepared for chromatography from glycosaminoglycans and proteoglycans of known compositions by digestion with chondroitinase ABC, with the exception of king crab cartilage glycosaminoglycan which was incubated sequentially with hyaluronidase and chondroitinase ABC. Disaccharides were extracted from the digestion mixtures in 80% ethanol, dried over nitrogen, resuspended in the HPLC solvent, and chromatographed at a flow rate of 1 ml/min. Unsaturated disaccharides in the column eluate were detected by continuous ultraviolet absorbance monitoring at 232 nm; alternatively, fractions were collected and assayed for uronic acid content or radioactivity. By utilizing the HPLC technique in conjunction with chondroitinase ABC and AC digestion and sulfatase hydrolysis, the epimeric structures of chondroitin sulfates E and H were confirmed. With this technique, rapid and reproducible analyses of chondroitin sulfate disaccharides generated from mouse mast cell proteoglycan and from glycosaminoglycans of squid cranial cartilage, shark skin, hagfish skin, and hagfish notocord were in close agreement with compositions obtained by other techniques.
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PMID:Analysis of polysulfated chondroitin disaccharides by high-performance liquid chromatography. 643 72


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