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Paulucci BP, Pereira J, Picciarelli P, Levy D, Di Francesco RC. Expression of cysteinyl leukotriene receptor 1 and 2 (CysLTR1 and CysLTR2) in the lymphocytes of hyperplastic tonsils: comparison between allergic and nonallergic snoring children. Int Forum Allergy Rhinol 2016; 6:1151-1158. [PMID: 27221082 DOI: 10.1002/alr.21798] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/07/2016] [Accepted: 04/21/2016] [Indexed: 01/08/2023]
Abstract
BACKGROUND Cysteinyl leukotriene receptor 1 and 2 (CysLTR1 and CysLTR2) are involved in allergic processes and play a role in adenotonsillar hyperplasia (AH). Clinically, only CysLTR1 may be blocked by montelukast. Our objective was to compare the expression of CysLTR1 and CysLTR2 in the B and T cells of hyperplasic tonsils of sensitized (SE) and control (NS) snoring children. METHODS Sixty children, 5 to 10 years of age, referred for adenotonsillectomy, were divided into SE and NS groups, according to their responses to the skin-prick test. Cells from the removed tissues were stained for CysLTR1, CysLTR2, CD19, and CD3 and counted via flow cytometry. messenger RNA (mRNA) expression of the CysLTRs genes was measured real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR). RESULTS The SE group showed reduced expression of the small CD3+/CysLTR1+ lymphocytes (4.6 ± 2.2 vs 6.5 ± 5.0; p = 0.04). Regarding the large lymphocytes, the SE group showed lower expression of CD3+/CysLTR1+ (40.9 ± 14.5 vs 47.6 ± 11.7; p = 0.05), CD19+/CysLTR1+ (44.6 ± 16.9 vs 54.1 ± 12.4; p = 0.01), and CD19+/CysLTR2+ (55.3 ± 11.3 vs 61.5 ± 12.6; p = 0.05) lymphocytes. Considering the total number of lymphocytes, the SE group had fewer CD3+/CysLTR1+ lymphocytes (11.1 ± 5.5 vs 13.7 ± 6.2; p = 0.04). All other cell populations exhibited reduced expression in the SE group without statistical significance. The expression of CysLTR2 was significantly higher (p < 0.05) than CysLTR1 in most studied cell populations. The mRNA expression did not show significant differences between the groups. CONCLUSION The expression of CysLTR is higher in the lymphocytes of the NS children, and CysLTR2 shows greater expression than CysLTR1 Respiratory allergies do not appear to be a stimulus for AH occurrence. Newer drugs capable of blocking both CysLTRs warrant further study.
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Affiliation(s)
- Bruno Peres Paulucci
- Department of Otolaryngology of Hospital das Clinicas, University of Sao Paulo, Sao Paulo, Brazil. ,
| | - Juliana Pereira
- Department of Hematology of Hospital das Clinicas, University of Sao Paulo, Sao Paulo, Brazil
| | - Patricia Picciarelli
- Department of Pathology of Hospital das Clinicas, University of Sao Paulo, Sao Paulo, Brazil
| | - Debora Levy
- Laboratory of Research in Hematology of Hospital das Clinicas, University of Sao Paulo, Sao Paulo, Brazil
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Nicolaou A, Mauro C, Urquhart P, Marelli-Berg F. Polyunsaturated Fatty Acid-derived lipid mediators and T cell function. Front Immunol 2014; 5:75. [PMID: 24611066 PMCID: PMC3933826 DOI: 10.3389/fimmu.2014.00075] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 02/11/2014] [Indexed: 01/10/2023] Open
Abstract
Fatty acids are involved in T cell biology both as nutrients important for energy production as well as signaling molecules. In particular, polyunsaturated fatty acids are known to exhibit a range of immunomodulatory properties that progress through T cell mediated events, although the molecular mechanisms of these actions have not yet been fully elucidated. Some of these immune activities are linked to polyunsaturated fatty acid-induced alteration of the composition of cellular membranes and the consequent changes in signaling pathways linked to membrane raft-associated proteins. However, significant aspects of the polyunsaturated fatty acid bioactivities are mediated through their transformation to specific lipid mediators, products of cyclooxygenase, lipoxygenase, or cytochrome P450 enzymatic reactions. Resulting bioactive metabolites including prostaglandins, leukotrienes, and endocannabinoids are produced by and/or act upon T leukocytes through cell surface receptors and have been shown to alter T cell activation and differentiation, proliferation, cytokine production, motility, and homing events. Detailed appreciation of the mode of action of these lipids presents opportunities for the design and development of therapeutic strategies aimed at regulating T cell function.
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Affiliation(s)
- Anna Nicolaou
- Manchester Pharmacy School, Faculty of Medical and Human Sciences, The University of Manchester , Manchester , UK
| | - Claudio Mauro
- Centre for Biochemical Pharmacology, William Harvey Research Institute, Queen Mary University of London , London , UK
| | - Paula Urquhart
- Manchester Pharmacy School, Faculty of Medical and Human Sciences, The University of Manchester , Manchester , UK
| | - Federica Marelli-Berg
- Centre for Biochemical Pharmacology, William Harvey Research Institute, Queen Mary University of London , London , UK
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Lone AM, Taskén K. Proinflammatory and immunoregulatory roles of eicosanoids in T cells. Front Immunol 2013; 4:130. [PMID: 23760108 PMCID: PMC3671288 DOI: 10.3389/fimmu.2013.00130] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 05/17/2013] [Indexed: 01/08/2023] Open
Abstract
Eicosanoids are inflammatory mediators primarily generated by hydrolysis of membrane phospholipids by phospholipase A2 to ω-3 and ω-6 C20 fatty acids that next are converted to leukotrienes (LTs), prostaglandins (PGs), prostacyclins (PCs), and thromboxanes (TXAs). The rate-limiting and tightly regulated lipoxygenases control synthesis of LTs while the equally well-controlled cyclooxygenases 1 and 2 generate prostanoids, including PGs, PCs, and TXAs. While many of the classical signs of inflammation such as redness, swelling, pain, and heat are caused by eicosanoid species with vasoactive, pyretic, and pain-inducing effects locally, some eicosanoids also regulate T cell functions. Here, we will review eicosanoid production in T cell subsets and the inflammatory and immunoregulatory functions of LTs, PGs, PCs, and TXAs in T cells.
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Affiliation(s)
- Anna Mari Lone
- Centre for Molecular Medicine Norway, Nordic EMBL Partnership, University of Oslo and Oslo University Hospital , Oslo , Norway ; Biotechnology Centre, University of Oslo , Oslo , Norway ; K.G. Jebsen Inflammation Research Centre, University of Oslo , Oslo , Norway
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Cook-Moreau JM, El-Makhour Hojeij Y, Barrière G, Rabinovitch-Chable HC, Faucher KS, Sturtz FG, Rigaud MA. Expression of 5-lipoxygenase (5-LOX) in T lymphocytes. Immunology 2007; 122:157-66. [PMID: 17484769 PMCID: PMC2265994 DOI: 10.1111/j.1365-2567.2007.02621.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
5-Lipoxygenase (5-LOX) is the key enzyme responsible for the synthesis of the biologically active leukotrienes. Its presence has been reported in cells of the myeloid lineage and B lymphocytes but has not been formally defined in T lymphocytes. In this study, we provide evidence for 5-LOX expression on both transcriptional and translational levels in highly purified peripheral blood T cells as well as in human T lymphoblastoid cell lines (MOLT4 and Jurkat). Messenger RNA (mRNA) of 5-LOX was amplified by conventional reverse transcription-polymerase chain reaction (RT-PCR; MOLT4 and Jurkat cells) and by in situ RT-PCR (T lymphocytes). 5-LOX protein expression was confirmed by Western blot and immunofluorescence studies. 5-LOX was present primarily in the cytoplasm with some nuclear localization and was translocated to the nuclear periphery after culture in a mitosis-supporting medium. Fluorescence-activated cell sorter analysis of different T-lymphocyte populations, including CD4, CD8, CD45RO, CD45RA, T helper type 2, and T-cell receptor-alphabeta and -gammadelta expressing cells, did not identify a differential distribution of the enzyme. Purified peripheral blood T lymphocytes were incapable of synthesizing leukotrienes in the absence of exogenous arachidonic acid. Jurkat cells produced leukotriene C(4) and a small amount of leukotriene B(4) in response to CD3-CD28 cross-linking. This synthesis was abolished by two inhibitors of leukotriene synthesis, MK-886 and AA-861. The presence of 5-LOX in T lymphocytes but the absence of endogenous lipoxygenase metabolite production compared to Jurkat cells may constitute a fundamental difference between resting peripheral lymphocytes and leukaemic cells.
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Affiliation(s)
- Jeanne M Cook-Moreau
- Laboratoire de Biochimie et Génétique Moléculaire, Faculté de Médecine, Limoges, France.
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Peters-Golden M, Gleason MM, Togias A. Cysteinyl leukotrienes: multi-functional mediators in allergic rhinitis. Clin Exp Allergy 2006; 36:689-703. [PMID: 16776669 PMCID: PMC1569601 DOI: 10.1111/j.1365-2222.2006.02498.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cysteinyl leukotrienes (CysLTs) are a family of inflammatory lipid mediators synthesized from arachidonic acid by a variety of cells, including mast cells, eosinophils, basophils, and macrophages. This article reviews the data for the role of CysLTs as multi-functional mediators in allergic rhinitis (AR). We review the evidence that: (1) CysLTs are released from inflammatory cells that participate in AR, (2) receptors for CysLTs are located in nasal tissue, (3) CysLTs are increased in patients with AR and are released following allergen exposure, (4) administration of CysLTs reproduces the symptoms of AR, (5) CysLTs play roles in the maturation, as well as tissue recruitment, of inflammatory cells, and (6) a complex inter-regulation between CysLTs and a variety of other inflammatory mediators exists.
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Zhang J, Alston MA, Huang H, Rabin RL. Human T cell cytokine responses are dependent on multidrug resistance protein-1. Int Immunol 2006; 18:485-93. [PMID: 16481346 DOI: 10.1093/intimm/dxh389] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Multidrug resistance protein-1 (MRP1) belongs to subfamily C of the ATP-binding cassette transporters, and exports leukotriene C(4) and organic anions including the fluorescent calcium indicator indo-1. The observation that leukocytes from patients with an autoimmune disease exported indo-1 at a higher rate than controls prompted the hypothesis that MRP1 contributes to the function of activated cells. To test this, we defined the expression of MRP1 on resting and activated human T cells, and determined whether T cell activation is dependent upon MRP1 function. MRP1 is expressed on resting memory but not on naive CD4 and CD8 T cells. After activation through the TCR, cord blood CD4 T cells express high levels of MRP1. Blockade of MRP1 with the specific inhibitor MK-571 abrogated superantigen-induced expression of IFN-gamma, tumor necrosis factor-alpha, IL-10, IL-2, IL-4 and CD69 by T cells without affecting their viability, and was reversible upon removal of MK-571 from the culture media. Electrophoretic mobility shift assays demonstrate that MRP1 blockade with MK-571 induces activation of the transcriptional repressor peroxisome proliferator-activated receptor-gamma in CD4 T cells, thus providing insight into the potential mechanism by which their responses are abrogated.
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Affiliation(s)
- Jinsong Zhang
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Bethesda, MD 20892-4555, USA
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Burgermeister E, Endl J, Scheuer WV. Activation of cytosolic phospholipase A2 in human T-lymphocytes involves inhibitor-kappaB and mitogen-activated protein kinases. Eur J Pharmacol 2003; 466:169-80. [PMID: 12679154 DOI: 10.1016/s0014-2999(03)01492-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The group IV 85 kDa cytosolic phospholipase A(2) regulates many aspects of innate immunity. However, the function of this enzyme in T-cells remains controversial. We show here that human peripheral blood lymphocytes and Jurkat cells express cytosolic phospholipase A(2) and produce prostaglandin A(2) and leukotriene B(4). Selective inhibitors of this enzyme suppressed Ca(2+)-ionophore-, mitogen- and T-cell receptor-mediated expression of interleukin-2 at the level of transcription from the promoter. Activation of mitogen-activated protein kinases (MAPK), degradation of inhibitor-kappaBalpha and transactivation by nuclear factor-kappaB (NFkappaB) were impaired as was the antigen-, lectin- and interleukin-2-driven proliferation of T-cells in vitro. Ligands of peroxisome proliferator-activated receptor-gamma (PPARgamma) induced rapid phosphorylation of MAPK in human monocytic but not in Jurkat cells. These data indicated that in T-cells, eicosanoids generated upon signal-activated cytosolic phospholipase A(2) promote NFkappaB-dependent interleukin-2 transcription via a PPARgamma-independent mechanism involving the MAPK-pathway.
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Affiliation(s)
- Elke Burgermeister
- Department of Biological Regulation, The Weizmann Institute of Science, I-76100 Rehovot, Israel
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Honig SM, Fu S, Mao X, Yopp A, Gunn MD, Randolph GJ, Bromberg JS. FTY720 stimulates multidrug transporter- and cysteinyl leukotriene-dependent T cell chemotaxis to lymph nodes. J Clin Invest 2003; 111:627-37. [PMID: 12618517 PMCID: PMC151892 DOI: 10.1172/jci16200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
FTY720 is a sphingosine-derived immunosuppressant. Phosphorylated FTY720 promotes T cell homing from spleen and peripheral blood to LNs by acting as an agonist for sphingosine-1-phosphate (S1P) receptors. Here we demonstrate that FTY720 enhances the activity of the sphingosine transporter Abcb1 (Mdr1) and the leukotriene C(4) transporter Abcc1 (Mrp1). Both transporters must be active for FTY720-mediated T cell migration and LN homing. Migration and homing driven by FTY720, phosphorylated FTY720, or S1P also require 5-lipoxygenase-mediated synthesis of cysteinyl leukotrienes and their efflux from the cell. FTY720-mediated LN homing events further downstream are dependent on CCL19, CCL21, VLA-4alpha, and CD44. Use of T cells deficient in 5-lipoxygenase, Abcb1, and Abcc1, and comparison of the effects of FTY720 with those of S1P, suggest a model of sequential engagement of Abcb1, SP1 receptors, 5-lipoxygenase, and Abcc1 to enhance T cell migration and homing.
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Affiliation(s)
- Shaun M Honig
- Carl C. Icahn Center For Gene Therapy and Molecular Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA
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Honig SM, Fu S, Mao X, Yopp A, Gunn MD, Randolph GJ, Bromberg JS. FTY720 stimulates multidrug transporter– and cysteinyl leukotriene–dependent T cell chemotaxis to lymph nodes. J Clin Invest 2003. [DOI: 10.1172/jci200316200] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Merhi‐Soussi F, Dominguez Z, Macovschi O, Dubois M, Savany A, Lagarde M, Prigent A. Human lymphocytes stimulate prostacyclin synthesis in human umbilical vein endothelial cells. Involvement of endothelial cPLA
2. J Leukoc Biol 2000. [DOI: 10.1189/jlb.68.6.881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Faten Merhi‐Soussi
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Zury Dominguez
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Olga Macovschi
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Madeleine Dubois
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Alain Savany
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Michel Lagarde
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
| | - Annie‐France Prigent
- INSERM U352, Laboratoire de Biochimie et Pharmacologie, Institut National des Sciences Appliquées de Lyon, Villeurbanne, France; and
- Cátedra de Patología General y Fisiopatología, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas
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Morita H, Takeda K, Yagita H, Okumura K. Immunosuppressive effect of leukotriene B(4) receptor antagonist in vitro. Biochem Biophys Res Commun 1999; 264:321-6. [PMID: 10529362 DOI: 10.1006/bbrc.1999.1523] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Leukotriene B(4) (LTB(4)), which is an arachidonic acid metabolite produced by the 5-lipoxygenase pathway and a well-characterized chemical mediator of inflammation, has been proposed to be an immune response modulator. Here we showed the constitutive expression of the LTB(4) receptor (LTB(4)R) in resting and activated T cells. We found that the LTB(4)R antagonist inhibited T cell proliferation induced by Con A, immobilized anti-CD3 mAb, or IL-2. This inhibitory effect was abolished by addition of LTB(4)R agonist. The LTB(4)R antagonist inhibited IL-2, IFN-gamma, and IL-4 production by anti-CD3-stimulated T cells and also inhibited IL-12-induced IFN-gamma production. Moreover, the LTB(4)R antagonist exerted an additive inhibitory effect to FK506 on T cell proliferation. These results suggest that LTB(4) is intrinsically involved in T cell activation to upregulate cytokine production and proliferation, and thus the LTB(4)R antagonist might be useful as an immunosuppressive agent.
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Affiliation(s)
- H Morita
- Department of Immunology, Juntendo University School of Medicine, Bunkyou-ku, Tokyo, Japan
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Chuang M, Severson DL. Metabolic fate of exogenous diacylglycerols in A10 smooth muscle cells. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1390:149-59. [PMID: 9507099 DOI: 10.1016/s0005-2760(97)00173-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The metabolic fate of exogenous diacylglycerols, 1-palmitoyl-2-[1-14C]oleoyl-sn-glycerol (2-[14C]POG) and 1-stearoyl-2-[1-14C]arachidonoyl-sn-glycerol (2-[14C]SAG), was determined after incubation of A10 smooth muscle cells with liposomal suspensions. Hydrolysis through a diacylglycerol (DG) lipase pathway was the predominant metabolic fate; more than 80% of cell-associated radioactivity from 2-[14C]POG and 2-[14C]SAG was recovered in lipolytic products, monoacylglycerol (MG) and fatty acids (FA), which were present in the incubation medium. Hydrolysis of 2-[14C]POG was reduced completely by tetrahydrolipstatin, a lipase inhibitor. Very little radioactivity from either 2-[14C]POG or 2-[14C]SAG was incorporated into triacylglycerol or phospholipids. DG lipase and kinase activities were measured by in vitro enzyme assays. 1-[1-14C]Palmitoyl-2-oleoyl-sn-glycerol (1-[14C]POG) was phosphorylated (kinase activity) to a greater extent than 2-[14C]SAG in assays with both soluble and particulate subcellular fractions from A10 cells. DG lipase activity (hydrolysis of 1-[14C]POG and 2-[14C]SAG) was markedly stimulated by the addition of 20 mM MgCl2 and 20 mM ATP to the assay. Under optimal assay conditions, DG lipase activity exhibited little substrate specificity. Our findings indicate that exogenous DG are mainly hydrolyzed by DG and MG lipases in A10 smooth muscle cells; as a result, signalling mechanisms responding to DG second messengers will be attenuated.
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Affiliation(s)
- M Chuang
- Smooth Muscle Research Group, Faculty of Medicine, The University of Calgary, 3330 Hospital Drive NW, Calgary, Alta., Canada
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Káldi K, Szászi K, Koncz G, Suszták K, Ligeti E. Arachidonic acid activatable electrogenic H+ transport in the absence of cytochrome b558 in human T lymphocytes. FEBS Lett 1996; 381:156-60. [PMID: 8641428 DOI: 10.1016/0014-5793(96)00105-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
To test the suggested structural relationship between the electrogenic H+ transporting system and the NADPH oxidase of phagocytes, the existence of the enzyme and the transport process was investigated in human tonsillar T lymphocytes. It is shown that tonsillar T cells possess an arachidonic acid activatable, Cd(2+)- and Zn(2+)-sensitive electrogenic H+ efflux pathway with similar properties as reported earlier in various phagocytic cells. The presence of cytochrome b558, the membrane component of the oxidase, could not be detected in tonsillar T lymphocytes either by immunoblot or by flow cytometric analysis. It is suggested that the electrogenic H+ transporting pathway is structurally independent of the NADPH oxidase complex.
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Affiliation(s)
- K Káldi
- Department of Physiology, Semmelweis University of Medicine, Budapest, Hungary
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