Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.32 (bromelain)
 1,025 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When normal mouse spleen cells are cultured in vitro, large numbers of cells develop that produce antibody toward antigens found on bromelain-treated mouse erythrocytes (BrMRBC). The in vitro culture also generates T cells that mediate DTH toward these antigens. We have suggested that under in vivo conditions, suppressor T cells maintain these immune responses at a low level but that this suppression wanes when the cells are cultured in vitro. The present study examines the effect of concanavalin A (Con A) on the in vitro development of humoral and cell-mediated immunity to Br-MRBC. Mitogenic concentrations of Con A prevented the development of both the PFC and TDTH responses toward BrMRBC. The Con A-induced suppression was due to the induction of suppressor T cells; thus the addition of Con A-activated cells to fresh spleen cell cultures prevented the development of both the PFC and TDTH response against BrMRBC.
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PMID:The in vitro suppression of spontaneous erythrocyte autoimmune responses with lymphocytes activated with concanavalin A. 36 37

There is an induction of anti-DNA antibodies in mice following the administration of bacterial lipopolysaccharides, Dextran sulfate and PPD, which is closely associated with the property of these substances to trigger a polyclonal B cell activation. In the experiments model of African trypanosomiasis there is also an intense polyclonal antibody synthesis paralleled by the formation of several autoantibodies: anti-DNA, anti-bromelain treated mouse red blood cells and antithymocyte antibodies.
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PMID:Relevance of polyclonal antibody formation to the development of autoimmunity : the model of African trypanosomiasis. 38 Mar 4

A high proportion of peritoneal cells from untreated mice, after 4--5 days in culture, develop into plaque-forming cells against bromelain-treated mouse red blood cells. The number of plaque-forming cells was increased significantly by exposing the peritoneal cells to ammonium chloride to lyse red blood cells before culture. Conversely, the increase was significantly inhibited by adding before culture untreated or bromelain-treated sheep or mouse red blood cells. Treated or untreated horse or rat red blood cells did not inhibit the increase. Treating peritoneal cells or subpopulations of peritoneal cells with anti-theta serum and complement before culture caused a significant increase in the number of plaque-forming cells against bromelain-treated red blood cells after 3--4 days of culture. Various procedures were used to fractionate peritoneal cells into B-cell enriched and B-cell depleted subpopulations before culture and after culture, to investigate whether some of the plaque-forming cells could be attributed to phagocytic cells. Generally, changes in the number of plaque-forming cells against bromelain-treated mouse red blood cells paralleled changes in B-cells. In some experiments the proportion of plaque-forming cells observed represented up to 85% of the B-cells present. The results suggest that the high level of autoreactivity is due to antibody production by B-cells and that phagocytic cells are not forming spurious plaques. Further, it appears that the autoimmunity is regulated by T-cells and can also be inhibited by mouse RBC.
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PMID:In vitro investigation of autoantibody-secreting peritoneal cells and their regulation. 38 87

Anti-inflammatory actions of proteases, bromelain (BR), trypsin (TR) and their mixed preparation (KT) were studied mainly in rabbits using various experimental test methods. Inhibitory action of edema formation induced by carrageenin was observed to be dose dependent with oral administrations of KT. This inhibitory action of KT was more remarkable than actions of BR and TR, suggesting a possible synergism between the latter two. Such action was also observed with non-steroidal anti-rheumatic drugs, phenylbutazone (PB), indomethacin and acetylsalicylic acid. Oral administration of KT exerted definite inhibition or a tendency toward inhibition against paw edema induced by dextran, histamine or egg albumin or skin edema induced by anti-rabbit serum and thermal stimulation. Furthermore, inhibition of vascular permeability increase induced by histamine and bradykinin as well as a tendency toward inhibition against protein exudation in CMC-pouch method were observed. On the other hand, contrary to PB, potent inhibitory action was not manifested in the persistent proliferative inflammation models, the granuloma formation induced formalin soaked filter paper and cotton pellet and the mustard edema. Therefore, it can be deduced that the inhibitory action of KT against edema formation may be dependent mainly on the inhibitory action of vascular permeability increase and the anti-inflammatory action may be specific for acute exudative inflammation.
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PMID:[Anti-inflammatory actions of proteases, bromelain, trypsin and their mixed preparation (author's transl)]. 39 51

The effects of inhibitors of cell division on polyclonal stimulation induced either by bacterial lipopolysaccharide (LPS) or by a synthetic adjuvant, MDP, were compared, using different target cells. Doses of colchicine that prevented 3H-thymidine incorporation also prevented the induction of antibodies against TNP and against an altered self antigen: bromelain-treated mouse red blood cells (br-MRBC). Under identical conditions, incubation with cytosine arabinoside (CA) strongly prevented the induction of anti-TNP PFC and to a lesser degree anti-SRBC PFC. However, the number of anti br-MRBC PFC was unchanged even when a dose of CA which inhibits totally the incorporation of 3H-thymidine was used. Our findings indicate that the general term "polyclonal stimulation" may concern at least two different types of cell populations and therefore we strongly stress the importance of choosing similar targets in comparative experiments.
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PMID:Effect of cell division inhibitors on polyclonal activation can vary according to the target cell used. 39 5

Isolation and characterization of the platelet aggregation inhibitory factor of bromelain have been presented in this study. Commercial bromelain consists of 3 major components as demonstrated by discontinuous sodium chloride gradient chromatography through carbixymethyl-sephadex column. Fraction I constituted approximately 19% of the total fraction. This fraction had no proteolytic activity or platelet aggregation inhibiting activity, but showed peroxidatic activity. Fraction II and III, which constituted the remainder of the fraction eluted with 135 mM and 800 mM NaCl concentrations, respectively, showed both proteolytic and inhibition of platelet aggregation, but no peroxidatic activity. Immunoelectrophoresis and polyacrylamide electrophoresis showed fraction I with beta-mobility while fraction II and III demonstrated gamma-mobility. It is suggested that the proteolytic activity is associated with the inhibition of platelet aggregation, since oxidation of fractions II and III with sodium tetrathionate abolished both activities. The mechanism of inhibition of platelet aggregation by bromelain is presently unknown but may involve its influence on the prostaglandin synthetic pathway of platelets.
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PMID:Chromatographic fractionation and characterization of the active platelet aggregation inhibitory factor from bromelain. 48 32

Prekallikrein activity in plasma was assayed using a synthetic peptidyl fluorogenic substrate (carbobenzoxy-L-phenylalanyl-L-arginine 4-methylcoumarinyl-7-amide), after activation of prekallikrein by acetone and kaolin. For total kininogen assay, the pretreatment of plasma at pH 2.0 was the best to eliminate bradykinin potentiators and kininase activity, before addition of trypsin to convert kininogen to bradykinin. Assay method of high molecular weight (HMW) kininogen was established by conversion of HMW-kininogen to bradykinin through activation of Hageman factor by glass powder and that of low molecular weight (LMW) kininogen was also by treatment of HMW-kininogen-depleted plasma in the same way as that for total kininogen. The marked reduction of prekallikrein and HMW-kininogen, not of LMW-kininogen, was found in pleural fluid of rat carrageenin pleurisy, and in plasma after i.v. injection of bromelain in rats. Members of the pedigree of hereditary angioneurotic edema patients also show low levels of prekallikrein and kininogens in plasma.
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PMID:Assay methods for prekallikrein and kininogens and their applications. 49 7

A 58-year-old pharmaceutical worker regularly developed asthma and rhinitis when handling bromelain, a purified protease of pineapple (Ananas comosus), at her work-place, where she had been employed for about 10 years. RAST and prick test showed strong positive reactions to bromelain. Both inhalation test with 0.03 mg bromelain and peroral challenge by ingestion of 190 g pineapple resulted in asthmatic reactions; the latter challenge was accompanied by gastrointestinal symptoms. Five of six workers sensitized to papain, showed positive RAST and skin test results to bromelain, two of them also showed immediate asthmatic reactions after bronchial challenge with bromelain. Out of sixty asthmatics not exposed to airborne proteases but probably to these as constituents of foods, two had positive skin test results and eight had positive RAST results to bromelain; but in no case was there clear evidence for clinical sensitization. The presented data prove conclusively that bromelain is capable of inducing IgE mediated respiratory and gastrointestinal allergic reactions. Furthermore, there is evidence for immunological cross-reaction between the two plant proteases bromelain and papain in human subjects.
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PMID:Allergic reactions, including asthma, to the pineapple protease bromelain following occupational exposure. 49 86

The sera of seven patients clinically hypersensitive to papain--in one case also to baromelain--and the sera of sixty asthmatic patients with allergies to other inhalant and food allergens were investigated for IgE antibody activity to the plant proteases papain and bromelain and to common allergens by RAST, confirmed in some sera by RAST inhibition. There seems to be a relation between the antibody reactions to papain and bromelain, in several cases also between the reactions to these proteases and to grass pollen and flour. Studies by RAST inhibition showed that papain, bromelain, wheat flour, rye flour, grass pollen and birch pollen mutually inhibit IgE antibody to each antigen; but the degree of inhibition varies among the different sera and allergens. Our results suggest that these allergens from various plants, besides having specific antigenic determinants, also possess similar or even identical antigenically active regions, leading to immunological cross-reactivity.
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PMID:Studies on the specificity of human IgE-antibodies to the plant proteases papain and bromelain. 49 87

Asparagine-linked oligosaccharides of stem bromelain glycopeptides were quantitatively released by digestion with the almond glycopeptidase which cleaves beta-aspartylglycosylamine linkage in glycopeptides with oligopeptide moieties. The primary structures of the two oligosaccharide components, (Man)3(Xyl)1(Fuc)1(GlcNAc)2 and (Man)2-(Xyl)1(Fuc)1(GlcNAc)2 were elucidated as Man alpha 1 leads to 6Man alpha 1 leads to 6[Xyl beta 1 leads to 2]Man beta 1 leads to 4GlcNAc beta 1 leads 4[Fuc alpha 1 leads to 3]GlcNAc and Man alpha 1 leads to 6[Xyl beta 1 leads to 2]Man beta 1 leads to 4 GlcNAc beta 1 leads to 4[Fuc alpha 1 leads to 3] GlcNAc, respectively.
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PMID:Complete structure of the carbohydrate moiety of stem bromelain. An application of the almond glycopeptidase for structural studies of glycopeptides. 50 Jun 6


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