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Papadopoulos C, Svingou M, Kekou K, Vergnaud S, Xirou S, Niotakis G, Papadimas GK. Aldolase A deficiency: Report of new cases and literature review. Mol Genet Metab Rep 2021; 27:100730. [PMID: 33665120 PMCID: PMC7907525 DOI: 10.1016/j.ymgmr.2021.100730] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/03/2021] [Accepted: 02/03/2021] [Indexed: 01/19/2023] Open
Abstract
Aldolase A (ALDOA), is the predominant isoform of aldolase in skeletal muscle and erythrocytes that catalyzes the reversibleconversion of fructose-1,6-bisphosphate to glyceraldehyde 3-phosphate. Autosomal recessive mutations in ALDOA, are extremely rare and cause hemolytic anemia and/or recurrent episodes of rhabdomyolysis, usually precipitated by fever. In this report we describe, clinical, laboratory and genetic data of two novel unrelated patients harboring mutations in the ALDOA gene who presented with episodic rhabdomyolysis, we review all previously published cases and discuss the most valuable features for diagnosis of this rare disorder. Recessive mutations in the ALDOA gene are rare cause of episodic rhabdomyolysis. We report two novel, unrelated patients harboring mutations in the ALDOA gene presenting with recurrent rhabdomyloysis. Patients with ALDOA deficiency show a rather homogeneous phenotype with episodes of rhabdomyolysis, associated either with hemolysis and/or learning disabilities.
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Affiliation(s)
- C Papadopoulos
- 1st Department of Neurology, Eginition Hospital, Medical School, National and Kapodistrian University of Athens, Greece
| | - M Svingou
- Laboratory of Medical Genetics, Medical School, National and Kapodistrian University of Athens, "Aghia Sophia" Children's Hospital, Athens, Greece
| | - K Kekou
- Laboratory of Medical Genetics, Medical School, National and Kapodistrian University of Athens, "Aghia Sophia" Children's Hospital, Athens, Greece
| | - S Vergnaud
- Département de Biochimie, Toxicologie et Pharmacologie, CHU de Grenoble, Centre de Référence Rhône-Alpes des Maladies NeuroMusculaires, Grenoble, France
| | - S Xirou
- 1st Department of Neurology, Eginition Hospital, Medical School, National and Kapodistrian University of Athens, Greece
| | - G Niotakis
- Pediatric Neurology Clinics, Venizeleion General Hospital, Heraklion, Crete, Greece
| | - G K Papadimas
- 1st Department of Neurology, Eginition Hospital, Medical School, National and Kapodistrian University of Athens, Greece
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Pomey MP, Denis JL, Bernier M, Vergnaud S, Préval J, Saint-Lary O. Innovation in Physician Remuneration in France: What Lessons for Canada? HRO-ORS 2019. [DOI: 10.13162/hro-ors.v7i2.3578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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3
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Vergnaud S, Riche VP, Tessier P, Mauduit N, Kaladji A, Gouëffic Y. Budget impact analysis of heparin-bonded polytetrafluoroethylene grafts (Propaten) against standard polytetrafluoroethylene grafts for below-the-knee bypass in patients with critical limb ischaemia in France. BMJ Open 2018; 8:e017320. [PMID: 29490953 PMCID: PMC5855478 DOI: 10.1136/bmjopen-2017-017320] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVES To evaluate the budget impact of progressive replacement of standard polytetrafluoroethylene (PTFE) grafts by heparin-bound PTFE (Propaten) for below-the-knee (BTK) bypass in patients with critical limb ischaemia (CLI). DESIGN From a review of the scientific literature, we calculated a theoretical BTK primary patency for Propaten grafts. Using the French hospital expenditure database (PMSI), we retrospectively estimated a rehospitalisation rate for standard PTFE grafts. From these data, a model was created to assess the budget impact of a progressive replacement from standard PTFE grafts to Propaten grafts over a 5-year horizon. We performed an univariate sensitivity analysis to assess the robustness of our results. SETTING French National Health Insurance (FNHI) perspective. PARTICIPANT Patients with CLI. MAIN OUTCOME MEASURES Budget impact analysis. RESULTS Data extraction from the PMSI revealed that 656 patients were treated with PTFE grafts in 2011 in French public hospitals for a BTK bypass. Assuming a 2-year survival rate of 76.8%, observed reinterventions rate for standard PTFE grafts at 24 months from the PMSI was 35.1%. The mean rehospitalisation cost was €10 689. The budget impact analysis based on these data found a net cumulative 5-year payer budget reduction of €112 420 in favour of Propaten, under the assumption of a 75.6% primary patency for Propaten grafts for a projected population of 3215 patients of which 801 received a Propaten graft. CONCLUSIONS Our budget impact analysis showed a positive impact on the national health insurance budget of the replacement of standard PTFE grafts by Propaten grafts for BTK bypass in patients with CLI in France. This supports the enactment of a reimbursement policy by the FNHI.
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Affiliation(s)
- Simon Vergnaud
- Innovation Cell, Partnership and Innovation Department, Directorate of Medical Affairs and Research, CHU de Nantes, Nantes, France
- Department of Medical Information, CHU de Nantes, Nantes, France
| | - Valéry-Pierre Riche
- Innovation Cell, Partnership and Innovation Department, Directorate of Medical Affairs and Research, CHU de Nantes, Nantes, France
| | - Philippe Tessier
- Innovation Cell, Partnership and Innovation Department, Directorate of Medical Affairs and Research, CHU de Nantes, Nantes, France
- SPHERE (EA4275) - Biostatistics, Clinical Research and Pharmaco-Epidemiology, Nantes University, Nantes, France
| | - Nicolas Mauduit
- Department of Medical Information, CHU de Nantes, Nantes, France
| | - Adrien Kaladji
- Service de Chirurgie Vasculaire, CHU Nantes, l'institut du Thorax, Nantes, France
| | - Yann Gouëffic
- Service de Chirurgie Vasculaire, CHU Nantes, l'institut du Thorax, Nantes, France
- Laboratoire de Physiopathologie de la Résorption Osseuse, Inserm-UN UMR-957, Nantes, France
- Faculté de médecine, Université de Nantes, Nantes, France
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Monneret D, Guergour D, Vergnaud S, Laporte F, Faure P, Gauchez A. Evaluation of LOCI® technology-based thyroid blood tests on the Dimension Vista® analyzer. Clin Biochem 2013. [DOI: 10.1016/j.clinbiochem.2012.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Smith LJ, Vergnaud S, Wright H, Bates C. P233 Death and the Respiratory Physician: Challenges to Providing Optimal End-Of-Life Care by Generalists. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Affiliation(s)
- S. M. Consoli
- a C-L Psychiatry Department of European Georges Pompidou Hospital, Paris Descartes University of Medicine
| | - N. Dantchev
- b Adult Psychiatry Department, Hôtel-Dieu Hospital, Paris Descartes University of Medicine, Paris
| | - S. Vergnaud
- c Psychiatric Unit, Hôtel-Dieu General Hospital, Paris
| | - C. Lemogne
- d C-L Psychiatry Department, European Georges Pompidou Hospital
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Millet C, Trocmé C, Vergnaud S, Papacatzis S, Descotes J, Morel F, Zaoui P. NADPH oxidases and MMP-9/TIMP-1 balance in human glomeruli: putative links to diabetic nephropathy. Int J Exp Pathol 2008. [DOI: 10.1111/j.0959-9673.2004.369ak.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Le Heuzey MF, Vergnaud S, Mouren MC. Traitements médicaux de l'enfant hyperactif : à propos des deux nouvelles formes de méthylphénidate commercialisées en France. Arch Pediatr 2006; 13:100-3. [PMID: 16239100 DOI: 10.1016/j.arcped.2005.09.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Multimodal treatment of hyperactive child includes psychostimulant medication, methylphenidate (MPH) marketed in France in its short-acting form since about ten years. We report our clinical experience about the first fifty methylphenidate responders who received one of the two sustained-release forms available since summer 2004, tablets of oros-methyphenidate (Concerta LP) or microgranule-filled capsules (Ritaline LP).
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Affiliation(s)
- M-F Le Heuzey
- Service de psychopathologie de l'enfant et de l'adolescent, hôpital Robert-Debré, 48, boulevard Sérurier, 75935 Paris cedex 19, France
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Hardy G, Vergnaud S, Lunardi J, Peoc'h M, Bessard G, Stanke-Labesque F. 5-lipoxygenase expression and activity in aorta from streptozotocin-induced diabetic rats. Prostaglandins Other Lipid Mediat 2005; 75:91-103. [PMID: 15789618 DOI: 10.1016/j.prostaglandins.2004.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We previously reported an activation of the 5-lipoxygenase pathway in aorta from streptozotocin-induced diabetic rats. The aim of this study was to investigate whether this activation was associated with an increased expression of 5-lipoxygenase, an increased cysteinyl leukotriene (CysLT) production in response to arachidonic acid or calcium ionophore A23187 and/or a hypersensitivity of the aorta to CysLTs in streptozotocin-induced diabetic rats. In aorta from diabetic and control rats, reverse transcriptase-PCR and western blot analysis with a specific 5-lipoxygenase antibody provided evidence for the presence of 5-lipoxygenase in aorta. However, the expression of 5-lipoxygenase was not significantly different between diabetic and control rats. Challenge by A23187 (10 microM) and arachidonic acid (10 microM and 0.1 mM) with or without A23187 (10 micromol/l) induced a significant increase of CysLT release (measured by enzyme immunoassay) that was in the same range in aorta from control and diabetic rats. In contrast, aortas from diabetic rats showed a greater sensitivity to LTC4 and LTD4 contractile effects. These data suggested that the activation of the 5-lipoxygenase pathway previously reported in streptozotocin-induced diabetic rats could be explained by an augmented sensitivity to CysLTs of the diabetic aorta.
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Affiliation(s)
- G Hardy
- Laboratory of Pharmacology, Laboratory HP2, University of Medicine, F-38706 La Tronche, France
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10
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Corne C, Durand M, Vergnaud S, Renversez JC, Lebrun C. [A very high level in a cardiac troponin I assay]. Ann Biol Clin (Paris) 2005; 63:326-8. [PMID: 15951266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2003] [Accepted: 01/28/2005] [Indexed: 05/02/2023]
Abstract
Cardiac troponin I (TnIc) is a very sensitive and also a specific marker of myocardial injuries. We report here, the clinical case of a patient with a particularly important and brutal increase of the troponin during a myocardial infarction. A 64-year-old man was admitted to hospital. He had a myocardial infarction associated to a cardiac necrosis and important cytolysis. The troponin assay was normal when the patient was hospitalized. The angioplasty coronary reperfusion brought about a massive troponin Ic release in systemic circulation: the assay made 10 hours after the appearance of the symptoms shows us an exceptional TnIc concentration that is greater than 4000 microg/L (baseline: 1,5 microg/L). This might be the highest value ever reported.
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Affiliation(s)
- C Corne
- Département de biologie integrée.
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Polack B, Vergnaud S, Paclet MH, Lamotte D, Toussaint B, Morel F. Protein delivery by Pseudomonas type III secretion system: Ex vivo complementation of p67(phox)-deficient chronic granulomatous disease. Biochem Biophys Res Commun 2000; 275:854-8. [PMID: 10973811 DOI: 10.1006/bbrc.2000.3399] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacterial type III secretion system drives the translocation of virulence factors into the cystosol of host target cells. In phagocytes and in Epstein-Barr virus immortalized B lymphocytes, NADPH oxidase generates O(-2) through an electron transfer chain the activity of which depends on the assembly of three, p67(phox), p47(phox) and p40(phox) cytosolic activating factors with Rac 1/2 and a membrane redox component, cytochrome b(558). In p67(phox) deficient chronic granulomatous disease (CGD) patients, p67-phox is missing and NADPH oxidase activity is abolished. ExoS is a virulence factor of Pseudomonas aeruginosa which is secreted via the type III secretion system: it was fused with p67(phox). Pseudomonas aeruginosa synthesized and translocated the hybrid ExoS-p67(phox) fusion protein into the cytosol of B lymphocytes via the type III secretion system. Purified ExoS-p67(phox) hybrid protein was as efficient as normal recombinant p67(phox) in cell-free reconstitution of NADPH oxidase activity. Therefore, ExoS-p67(phox) was transferred via the type III secretion system of Pseudomonas aeruginosa into the cytosol of B lymphocytes from a p67(phox)-deficient CGD patient and functionally reconstituted NADPH oxidase activity. In the complementation process, ExoS acted as a molecular courier for protein delivery: the reconstitution of an active NADPH oxidase complex suggests type III secretion system to be a new approach for cellular therapy.
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Affiliation(s)
- B Polack
- Groupe d'étude du processus inflammatoire (GREPI), MENRT EA 2938, Centre Hospitalier Universitaire de Grenoble, Grenoble, France.
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Paclet MH, Coleman AW, Vergnaud S, Morel F. P67-phox-mediated NADPH oxidase assembly: imaging of cytochrome b558 liposomes by atomic force microscopy. Biochemistry 2000; 39:9302-10. [PMID: 10924123 DOI: 10.1021/bi000483j] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
NADPH oxidase activity depends on the assembly of the cytosolic activating factors, p67-phox, p47-phox, p40-phox, and Rac with cytochrome b(558). The transition from an inactive to an active oxidase complex induces the transfer of electrons from NADPH to oxygen through cytochrome b(558). The assembly of oxidase complex was studied in vitro after reconstitution in a heterologous cell-free assay by using true noncontact mode atomic force microscopy. Cytochrome b(558) was purified from neutrophils and Epstein-Barr virus-immortalized B lymphocytes and incorporated into liposomes. The effect of protein glycosylation on liposome size and oxidase activity was investigated. The liposomes containing the native hemoprotein purified from neutrophils had a diameter of 146 nm, whereas after deglycosylation, the diameter was reduced to 68 nm, although oxidase activity was similar in both cases. Native cytochrome b(558) was used after purification in reconstitution experiments to investigate the topography of NADPH oxidase once it was assembled. For the first time, atomic force microscopy illustrated conformational changes of cytochrome b(558) during the transition from the inactive to the active state of oxidase; height measurements allow the determination of a size of 4 nm for the assembled complex. In the processes that were studied, p67-phox displayed a critical function; it was shown to be involved in both assembly and activation of oxidase complex while p47-phox proceeded as a positive effector and increased the affinity of p67-phox with cytochrome b(558), and p40-phox stabilizes the resting state. The results suggest that although an oligomeric structure of oxidase machinery has not been demonstrated, allosteric regulation mechanisms may be proposed.
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Affiliation(s)
- M H Paclet
- GREPI EA 2938 MENRT laboratoire Enzymologie, CHU Grenoble BP 217, 38043 Grenoble Cedex, France
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Vergnaud S, Paclet MH, El Benna J, Pocidalo MA, Morel F. Complementation of NADPH oxidase in p67-phox-deficient CGD patients p67-phox/p40-phox interaction. Eur J Biochem 2000; 267:1059-67. [PMID: 10672014 DOI: 10.1046/j.1432-1327.2000.01097.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Chronic granulomatous disease (CGD) is due to a functional defect of the O2- generating NADPH oxidase of phagocytes. Epstein-Barr-virus-immortalized B lymphocytes express all the constituents of oxidase with activity 100 times less than that of neutrophils. As in neutrophils, oxidase activity of Epstein-Barr-virus-immortalized B lymphocytes was shown to be defective in the different forms of CGD; these cells were used as a model for the complementation studies of two p67-phox-deficient CGD patients. Reconstitution of oxidase activity was performed in vitro by using a heterologous cell-free assay consisting of membrane-suspended or solubilized and purified cytochrome b558 that was associated with cytosol or with the isolated cytosolic-activating factors (p67-phox, p47-phox, p40-phox) from healthy or CGD patients. In p67-phox-deficient CGD patients, two cytosolic factors are deficient or missing: p67-phox and p40-phox. Not more than 20% of oxidase activity was recovered by complementing the cytosol of p67-phox-deficient patients with recombinant p67-phox. On the contrary, a complete restoration of oxidase activity was observed when, instead of cytosol, the cytosolic factors were added in the cell-free assay after isolation in combination with cytochrome b558 purified from neutrophil membrane. Moreover, the simultaneous addition of recombinant p67-phox and recombinant p40-phox reversed the previous complementation in a p40-phox dose-dependent process. These results suggest that in the reconstitution of oxidase activity, p67-phox is the limiting factor; the efficiency of complementation depends on the membrane tissue and the cytosolic environment. In vitro, the transition from the resting to the activated state of oxidase, which results from assembling, requires the dissociation of p40-phox from p67-phox for efficient oxidase activity. In the process, p40-phox could function as a negative regulatory factor and stabilize the resting state.
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Affiliation(s)
- S Vergnaud
- GREPI, Laboratoire d'Enzymologie, CHU, Grenoble, France; INSERM U. 479, CHU, Bichat, Paris, France
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El Benna J, Dang PM, Andrieu V, Vergnaud S, Dewas C, Cachia O, Fay M, Morel F, Chollet-Martin S, Hakim J, Gougerot-Pocidalo MA. P40phox associates with the neutrophil Triton X-100-insoluble cytoskeletal fraction and PMA-activated membrane skeleton: a comparative study with P67phox and P47phox. J Leukoc Biol 1999; 66:1014-20. [PMID: 10614785 DOI: 10.1002/jlb.66.6.1014] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
NADPH oxidase is an O2*- -generating enzyme found in phagocytes such as neutrophils. It is composed of a membrane-bound cytochrome b, the cytosolic proteins p67phox, p47phox, p40phox, and the G-protein p21rac. The system is dormant in resting cells but acquires catalytic activity on exposure to appropriate stimuli. Cytochrome b, p67phox, p47phox, and rac2 associate with the cytoskeleton and membrane skeleton of activated neutrophils. It is not known whether p40phox associates with the cytoskeleton. The purpose of this study was to analyze the subcellular distribution of p40phox. When resting neutrophils were lysed in Triton X-100 or octyl glucoside buffer and separated into detergent-soluble and detergent-insoluble fractions, p40phox and p67phox were mainly associated with the detergent-insoluble fraction (defined as the cytoskeleton), whereas p47phox was mainly found in the soluble fraction. Neutrophil activation by phorbol myristate acetate (PMA) induced p47phox translocation to the cytoskeleton but did not affect the distribution of p40phox or p67phox. Using immunofluorescence confocal microscopy, we found that p40phox colocalized with filamentous actin. In neutrophils from a p67phox-deficient patient with detectable p40phox, p40phox associated with the cytoskeleton only after activation by PMA. A complex containing the three proteins was isolated from the cytoskeleton of activated neutrophils. When activated membranes were treated with Triton X-100 buffer, p40phox, p47phox, and p67phox were found in the membrane skeleton enriched in NADPH-oxidase activity; some p40phox and p47phox was found in the soluble membrane fraction, but no p67phox was detected. These findings show that p40phox, like p67phox and p47phox, binds to the cytoskeleton and membrane skeleton. In addition, p40phox can dissociate from p67phox in activated membranes.
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Affiliation(s)
- J El Benna
- INSERM U.479, CHU-Faculté de Médecine Xavier Bichat, Paris, France.
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Batot G, Paclet MH, Doussière J, Vergnaud S, Martel C, Vignais PV, Morel F. Biochemical and immunochemical properties of B lymphocyte cytochrome b558. Biochim Biophys Acta 1998; 1406:188-202. [PMID: 9573361 DOI: 10.1016/s0925-4439(98)00004-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Like neutrophils, Epstein-Barr virus (EBV)-immortalized B lymphocytes express all constituents of the NADPH oxidase complex necessary to generate superoxide anion O2-. The NADPH oxidase activity in EBV-B lymphocytes is only 5% of that measured in neutrophils upon PMA stimulation. Cytochrome b558 is the sole redox membrane component of NADPH oxidase; it is the protein core around which cytosolic factors assemble in order to mediate oxidase activity. In the present study, we have compared the structural and functional properties of cytochrome b558 from EBV-B lymphocytes and neutrophils. Cytochrome b558 from EBV-B lymphocyte plasma membrane, like that from neutrophils, is characterized by a heterodimeric structure with a highly glycosylated beta subunit, known as gp91-phox. While the amount of cytochrome b558 recovered after purification from EBV-B lymphocytes (approximately 0.24 nmol from 1010 cells) was low compared to that recovered from neutrophils (approximately 10 nmol), the biochemical properties of purified cytochrome b558 from both EBV-B lymphocytes and neutrophils were quite similar with respect to their differential spectra, redox potential, and FAD binding site. Once cytochrome b558 was extracted from the EBV-B lymphocyte membrane, it was able to mediate, in a reconstituted system of O2- production the same oxidase turnover as that found for cytochrome b558 extracted from neutrophils. A comparison between membrane bound and soluble cytochrome b558 suggested that the weak oxidase activity measured in intact EBV-B cells might be the result not only of the small amount of expressed cytochrome b558, but also of a defect of the activation process in lymphocyte membrane.
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Affiliation(s)
- G Batot
- GREPI, JE-UJF, Laboratoire d'Enzymologie, CHU, Grenoble, France
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