Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A concise review of the ultrastructural features and physiological properties of eosinophils is presented with the aim of delineating those properties of eosinophils that set them apart from other granulocytes. It has become clear that eosinophols are subject to chemotaxis by attractants that do not affect other cells (e.g., histamine, ECF-A, ESP) and that they contain antiflogistic agents (arylsulfatase IIB, peroxidase) that neutralize specific substances known to elicit the inflammatory response. The mechanisms underlying eosinophilia in a variety of cutaneous disorders are analyzed in the light of this information.
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PMID:Eosinophil function related to cutaneous disorders. 35 61

To study the various stages of human mononuclear phagocyte maturation, we cultivated bone marrow in an in vitro diffusion chamber with the cells growing in suspension and upon a dialysis membrane. At 2, 7, and 14 days, the cultured cells were examined by electron microscopy and cytochemical techniques for peroxidase and for more limited analysis of acid phosphatase and arylsulfatase. Peroxidase was being synthesized in promonocytes of 2- and 7-day cultures, as evidenced by reaction product in the rough-surfaced endoplasmic reticulum, Golgi complex, and storage granules. Peroxidase synthesis had ceased in monocytes and the enzyme appeared only in some granules. By 7 days, large macrophages predominated, containing numerous peroxidase-positive storage granules, and heterophagy of dying cells was evident. By 14 days, the most prevalent cell type was the large peroxidase-negative macrophage. Thus, peroxidase is present in high concentrations in immature cells but absent at later stages, presumably a result of degranulation of peroxidase-positive storage granules. Clusters of peroxidase-negative macrophages with indistinct borders (epithelioid cells), as well as obvious multinucleated giant cells, were noted. Frequently, the interdigitating plasma membranes of neighboring macrophages showed a modification resembling a septate junction--to our knowledge, representing the first documentation of this specialized cell contact between normal macrophages. We suggest that such junctions may serve as zones of adhesion between epithelioid cells.
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PMID:Differentiation of macrophages from normal human bone marrow in liquid culture. Electron microscopy and cytochemistry. 65 15

We studied the effect of hematopoietic growth factors (granulocyte-macrophage colony-stimulating factor [GM-CSF], granulocyte [G]-CSF, interleukin (IL)-1, IL-3, IL-5, IL-6, and macrophage [M]-CSF) on differentiation and functional activity of human eosinophilic HL-60 cells (Eos-HL-60) and compared them with effects on parental HL-60 promyelocytic leukemia cells. Purified biosynthetic GM-CSF and IL-5 enhanced cell proliferation and induced eosinophilic differentiation in the eosinophilic subline in both liquid and agar cultures. IL-3 and IL-6 stimulated cell proliferation but had no effect on cell differentiation, whereas IL-1 and G-CSF affected neither differentiation nor proliferation of Eos-HL-60 cells under the conditions tested. GM-CSF-, IL-3-, and IL-5-treated Eos-HL-60 cells showed increased O2- production in response to phorbol esters (PMA), enhanced phagocytosis of Candida albicans, and release of the enzymes arylsulfatase, beta-glucuronidase and eosinophil peroxidase (EPO). The degranulation of eosinophils induced by GM-CSF, IL-5, and IL-3 may have relevance to the potential clinical toxicity of these hematopoietins, which also stimulate eosinophilopoiesis. G-CSF had no effect on enzyme release, oxidative metabolism, or phagocytic capacity of Eos-HL-60 cells. IL-5 did not affect proliferation, differentiation, or enzyme release in promyelocytic HL-60 cells. These results indicate the specificity of IL-5 for the eosinophil lineage, confirm the effects of GM-CSF and IL-3 on eosinophilopoiesis and mature eosinophil function in a model system, and indicate the absence of G-CSF and IL-1 stimulation of eosinophils. The Eos-HL-60 line is a useful model for studying human eosinophil responses to cytokines.
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PMID:Differentiation and functional activity of human eosinophilic cells from an eosinophil HL-60 subline: response to recombinant hematopoietic growth factors. 137 88

To investigate the potential role of lysosomes in cirrhosis, we analyzed the activity of lysosomal enzymes in rats exposed long-term to phenobarbital and carbon tetrachloride. The activity of lysosomal enzymes was markedly increased in the homogenate of cirrhotic livers (e.g., arylsulfatase 9 +/- S.D.2 vs. 16 +/- 6 nmoles.min-1.mg-1 in control rats and cirrhotic rats, respectively; p less than 0.001). The corresponding plasma levels were also increased (7 +/- 1 vs. 12 +/- 3 nmoles.min-1.mg-1; p less than 0.01), whereas biliary excretion was diminished (16 +/- 7 vs. 7 +/- 2 pmol.min-1.gm liver-1; p less than 0.05) in cirrhotic rats. Stereological quantification of lysosomes visualized cytochemically revealed an increase of pericanalicular lysosomes averaging 1.5 +/- 0.4 around a canaliculus in controls and 3.7 +/- 1.0 in cirrhotic rats (p less than 0.01). Because this suggested a defect in the transcellular vesicular pathway, we investigated the biliary excretion of horseradish peroxidase and epidermal growth factor in perfused livers. Bile flow and total horseradish peroxidase excretion were similar in control rats and cirrhotic rats. However, the early peak of biliary horseradish peroxidase excretion--usually taken as evidence of paracellular transport--was increased in cirrhotic rats (13 +/- 7 vs. 57 +/- 22%; p less than 0.01), whereas the second peak--reflecting the transcellular vesicular pathway(s)--was markedly reduced (87 +/- 7 vs. 43 +/- 22%; p less than 0.001). A similar reduction in the biliary excretion of intact epidermal growth factor and of its degradation products was found. These results demonstrate an increased number of lysosomes in hepatocytes of cirrhotic livers; this appears to be the result of accumulation rather than proliferation, in view of the reduced transcellular vesicular movement of different markers into bile.
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PMID:Hepatic accumulation of lysosomes and defective transcytotic vesicular pathways in cirrhotic rat liver. 139 8

Recently four tissue toxic proteins namely major basic protein (MBP), eosinophil peroxidase (EPO), eosinophil-derived neurotoxin (EDN), and eosinophil cationic protein (ECP) were found in eosinophilic leucocytes. Although the characteristics of these proteins concerning tissue damage in the local site of type I allergic reaction have been investigated mainly in lower respiratory tract, the actual clinico-pathological roles of these proteins in nasal allergy are not clarified. Contrary, eosinophils also have histaminase, arylsulfatase, phospholipase D, which are considered to act on a negative feedback mechanism in allergic reaction through inactivation of chemical mediators. Therefore, estimation of ECP and simultaneously arylsulfatase B in nasal secretion and the sera from patients with nasal allergy may clarify the dynamics of clinico-pathological state, especially in the late phase of allergic reaction in each patients. ECP concentrations in the nasal secretions from 22 patients and in the sera from 12 patients with nasal allergy were measured by RIA method. The activities of arylsulfatase B in the nasal secretions and the sera were also estimated in the same specimens as ECP by measuring its hydrolytic activity using p-nitro cathecol sulfate as a substrate. The results obtained were as follows; 1) There was a significant correlation between ECP concentrations in the nasal secretions and the severities of clinical symptoms, especially the degree of nasal obstruction. ECP concentrations also significantly correlated to the score of eosinophilic leucocytes in the nasal smears. 2) The serum ECP concentrations significantly correlated to the number of eosinophilic leucocytes in the peripheral blood, and also showed slight tendency of correlation to the severity of clinical symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Study on eosinophil cationic protein (ECP) and arylsulfatase B in nasal secretions and sera from patients with nasal allergy]. 188 31

Although endosomes and lysosomes are associated with different subcellular functions, we present evidence that a lysosomal enzyme, arylsulfatase-A, is present in prelysosomal vesicles which constitute part of the endosomal compartment. When human cultured fibroblasts were subfractionated with Percoll gradients, arylsulfatase-A activity was enriched in three subcellular fractions: dense lysosomes, light lysosomes, and light membranous vesicles. Pulsing the cells for 1 to 10 min with the fluid-phase endocytic marker, horseradish peroxidase, showed that endosomes enriched with the marker were distributed partly in the light lysosome fraction but mainly in the light membranous fraction. By pulsing the fibroblasts for 10 min with horseradish peroxidase conjugated to colloidal gold and then staining the light membranous and light lysosomal fractions for arylsulfatase-A activity with a specific cytochemical technique, the endocytic marker was detected under the electron microscope in the same vesicles as the lysosomal enzyme. The origin of the lysosomal enzyme in this endosomal compartment was shown not to be acquired through mannose 6-phosphate receptor-mediated endocytosis of enzymes previously secreted from the cell. Together with our recent finding that the light membranous fraction contains prelysosomes distinct from bona fide lysosomes and was highly enriched with newly synthesized arylsulfatase-A molecules, these results demonstrate that prelysosomes also constitute part of the endosomal compartment to which intracellular lysosomal enzymes are targeted.
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PMID:Presence of a lysosomal enzyme, arylsulfatase-A, in the prelysosome-endosome compartments of human cultured fibroblasts. 256 59

Eosinophils derived from HL-60 cells share many of the abnormalities of granule histochemistry and morphology frequently seen in eosinophils of patients with certain malignancies, especially those seen in acute myelomonocytic leukemia with abnormal eosinophils (FAB class M4eo). In order to understand the pathogenesis of these abnormalities, four enzymes, characteristic of the eosinophil, were studied in HL-60 promyelocytic leukemia cells at various stages of eosinophilic differentiation. Using biochemical and ultrahistochemical techniques, the following differences from normal eosinophil development were demonstrated. First, both myeloperoxidase and eosinophil peroxidase coexisted in the population of maturing HL-60 eosinophils. Second, the granules formed from the condensation of material in vacuoles which were derived from dilated segments of the endoplasmic reticulum; the role of the Golgi apparatus in processing of peroxidase appeared minimal. Third, low levels of lysophospholipase and arylsulfatase were present in the cells compared to normal eosinophils. Finally, crystallizations resembling precursor structures of Auer rods appeared in the granules of about 5% of the cells. These findings suggest that several disorders of the control of protein synthesis and processing exist in HL-60 eosinophils which may be responsible for the abnormal granule morphology and histochemistry.
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PMID:Synthesis of eosinophil-associated enzymes in HL-60 promyelocytic leukemia cells. 301 41

Human NK activity is known to be associated with a population of large granular lymphocytes (LGL) exhibiting several immunophenotypic surface markers including Leu-11a (NKP-15), Leu-7 (HNK-1), Leu-3a (T4), and Leu-2a (T8). Based upon correlation with cytolytic activity, Leu-11a is now considered the most specific antigenic marker for human NK cells. Present investigation compared the ultrastructure of cells expressing Leu-11a, Leu-7, Leu-3a, and Leu-2a, both in human peripheral blood lymphocytes (PBL) and the purified LGL fraction. Subcellular cytochemical reactions were investigated in Leu-7+ or Leu-11a+ PBL or LGL and in cells conjugated with K562 targets (indicating NK cytolytic potential). The surface markers, localized with monoclonal antibodies, were detected by immunoelectron microscopy by using direct or indirect avidin-biotin-peroxidase (ABC) or colloidal gold methods. A peroxidase-colloidal gold double-labeling system was used to identify subsets of Leu-7+ or Leu-11a+ cells. Previously described ultrastructural features of LGL including a villous surface, reniform nuclei, low nuclear/cytoplasm ratios, and abundant cytoplasm with vesicles, vacuoles, electron-dense granules, parallel tubular arrays (PTA), or paracrystalline inclusions were associated with Leu-7+, Leu-11a+, Leu-7+/Leu-11a+, Leu-7+/Leu-11a-, and Leu-7-/Leu-11a+ PBL or LGL. Results showed that the Leu-7+/Leu-11a+ cells were the most abundant NK cells in PBL. Lymphocyte subsets with Leu-3a or Leu-2a surface marker showed some ultrastructural features including PTA similar to Leu-7+ cells and Leu-11a+ cells, and their subsets. These T-cells appeared ultrastructurally more similar to the Leu-7+/Leu-11a- subset. Cytochemical studies showed that electron-dense cytoplasmic granules and PTA typical of the Leu-11a+ cells and Leu-7+ cells contained glycoprotein, acid phosphatase, and arylsulfatase. Large cytoplasmic vacuoles were heterogeneous and typically contained electron-dense material with DAB reactivity, membranous material, PTA, and/or paracrystalline inclusions. Glycoprotein, acid phosphatase, and arylsulfatase, and peroxidase reactive material were also found in these vacuoles. These features suggested that the vacuoles could be secondary lysosomes. The coexistence of intact PTA or degenerating PTA in the same vacuoles with paracrystalline inclusions suggested that the latter are possibly derived from PTA.
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PMID:Immunoultrastructural studies of human NK cells: I. Ultracytochemistry and comparison with T cell subsets. 355 61

Histochemical procedures for PMN granule enzymes were carried out on smears prepared from normal rabbit bone marrow, and the smears were examined by light microscopy. For each of the enzymes tested, azo dye and heavy metal techniques were utilized when possible. The distribution and intensity of each reaction were compared to the distribution of azurophil and specific granules in developing PMN. The distribution of peroxidase and six lysosomal enzymes (acid phosphatase, arylsulfatase, beta-galactosidase, beta-glucuronidase, esterase, and 5'-nucleotidase) corresponded to that of azurophil granules. Progranulocytes contained numerous reactive granules, and later stages contained only a few. The distribution of one enzyme, alkaline phosphatase, corresponded to that of specific granules. Reaction product first appeared in myelocytes, and later stages contained numerous reactive granules. The results of tests for lipase and thiolacetic acid esterase were negative at all developmental stages. Both types of granules stained for basic protein and arginine. It is concluded that azurophil and specific granules differ in their enzyme content. Moreover, a given enzyme appears to be restricted to one of the granules. The findings further indicate that azurophil granules are primary lysosomes, since they contain numerous lysosomal, hydrolytic enzymes, but the nature of specific granules is uncertain since, except for alkaline phosphatase, their contents remain unknown.
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PMID:Differences in enzyme content of azurophil and specific granules of polymorphonuclear leukocytes. I. Histochemical staining of bone marrow smears. 487 49

During their differentiation in the bone marrow, eosinophilic leukocytes synthesize a number of enzymes and package them into secretory granules. The pathway by which three enzymes (peroxidase, acid phosphatase, and arylsulfatase) are segregated and packaged into specific granules of eosinophils was investigated by cytochemistry and electron microscopy. During the myelocyte stage, peroxidase is present within (a) all rough ER cisternae, including transitional elements and the perinuclear cisterna; (b) clusters of smooth vesicles at the periphery of the Golgi complex; (c) all Golgi cisternae; and (d) all immature and mature specific granules. At later stages, after granule formation has ceased, peroxidase is not seen in ER or Golgi elements and is demonstrable only in granules. The distribution of acid phosphatase and arylsulfatase was similar, except that the reaction was more variable and fully condensed (mature) granules were not reactive. These results are in accord with the general pathway for intracellular transport of secretory proteins demonstrated in the pancreas exocrine cell by Palade and coworkers. The findings also demonstrate (a) that in the eosinophil the stacked Golgi cisternae participate in the segregation of secretory proteins and (b) that the entire rough ER and all the Golgi cisternae are involved in the simultaneous segregation and packaging of several proteins.
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PMID:Segregation and packaging of granule enzymes in eosinophilic leukocytes. 545


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