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Montague SJ, Price J, Pennycott K, Pavey NJ, Martin EM, Thirlwell I, Kemble S, Monteiro C, Redmond-Motteram L, Lawson N, Reynolds K, Fratter C, Bignell P, Groenheide A, Huskens D, de Laat B, Pike JA, Poulter NS, Thomas SG, Lowe GC, Lancashire J, Harrison P, Morgan NV. Comprehensive functional characterization of a novel ANO6 variant in a new patient with Scott syndrome. J Thromb Haemost 2024; 22:2281-2293. [PMID: 38492852 DOI: 10.1016/j.jtha.2024.02.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 02/09/2024] [Accepted: 02/29/2024] [Indexed: 03/18/2024]
Abstract
BACKGROUND Scott syndrome is a mild platelet-type bleeding disorder, first described in 1979, with only 3 unrelated families identified through defective phosphatidylserine (PS) exposure and confirmed by sequencing. The syndrome is distinguished by impaired surface exposure of procoagulant PS on platelets after stimulation. To date, platelet function and thrombin generation in this condition have not been extensively characterized. OBJECTIVES Genetic and functional studies were undertaken in a consanguineous family with a history of excessive bleeding of unknown cause. METHODS A targeted gene panel of known bleeding and platelet genes was used to identify possible genetic variants. Platelet phenotyping, flow adhesion, flow cytometry, whole blood and platelet-rich plasma thrombin generation, and specialized extracellular vesicle measurements were performed. RESULTS We detected a novel homozygous frameshift variant, c.1943del (p.Arg648Hisfs∗23), in ANO6 encoding Anoctamin 6, in a patient with a bleeding history but interestingly with normal ANO6 expression. Phenotyping of the patient's platelets confirmed the absence of PS expression and procoagulant activity but also revealed other defects including reduced platelet δ granules, reduced ristocetin-mediated aggregation and secretion, and reduced P-selectin expression after stimulation. PS was absent on spread platelets, and thrombi formed over collagen at 1500/s. Reduced thrombin generation was observed in platelet-rich plasma and confirmed in whole blood using a new thrombin generation assay. CONCLUSION We present a comprehensive report of a patient with Scott syndrome with a novel frameshift variant in AN06, which is associated with no platelet PS exposure and markedly reduced thrombin generation in whole blood, explaining the significant bleeding phenotype observed.
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Affiliation(s)
- Samantha J Montague
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Joshua Price
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Katherine Pennycott
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Natasha J Pavey
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Eleyna M Martin
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Isaac Thirlwell
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Samuel Kemble
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Catarina Monteiro
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Lily Redmond-Motteram
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Natalie Lawson
- Haemophilia Unit, Birmingham Children's Hospital, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Katherine Reynolds
- Haemophilia Unit, Birmingham Children's Hospital, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Carl Fratter
- Oxford Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Patricia Bignell
- Oxford Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | | | - Dana Huskens
- Synapse Research Institute, Maastricht, the Netherlands
| | - Bas de Laat
- Synapse Research Institute, Maastricht, the Netherlands
| | - Jeremy A Pike
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, the Midlands, United Kingdom
| | - Natalie S Poulter
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, the Midlands, United Kingdom
| | - Steven G Thomas
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, the Midlands, United Kingdom
| | - Gillian C Lowe
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom; Comprehensive Care Haemophilia Centre, University Hospital Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | - Jonathan Lancashire
- Haemophilia Unit, Birmingham Children's Hospital, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Paul Harrison
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Neil V Morgan
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom.
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2
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Babuty A, Debord C, Drillaud N, Eveillard M, Trossaert M, Ternisien C, Sigaud M, Cador E, Béné MC, Fouassier M. Prothrombin consumption as an indicator of hemorrhagic phenotype in mild platelet function disorders. Eur J Haematol 2023; 111:787-795. [PMID: 37553915 DOI: 10.1111/ejh.14079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/28/2023] [Accepted: 07/31/2023] [Indexed: 08/10/2023]
Abstract
BACKGROUND The bleeding risk of patients with mild platelet function disorders is difficult to assess and their phenotype remains ill-explored. AIM This study was designed to establish a comprehensive biological phenotype of patients with mild platelet function disorders. METHODS Twenty patients were included with persistent abnormal light transmission aggregometry (LTA). The ISTH bleeding assessment tool (ISTH-BAT) was assessed to identify laboratory analyses associated with an abnormal hemorrhagic score. RESULTS The majority of patients had defects that might affect Gαi protein signaling pathways or minor abnormalities. No LTA nor flow cytometry parameters were associated with an above-normal hemorrhagic score. However, prothrombin consumption, which corresponds to the ratio of serum residual factor II to plasma residual factor II, was significantly higher (p = .006) in the abnormal ISTH-BAT group (mean = 14%, SD = 6) compared with the normal ISTH-BAT group (mean = 8%, SD 4). Prothrombin consumption was significantly associated with ISTH-BAT score (r = .5287, IC 95% 0.0986-0.7924, p = .0165). CONCLUSION In this group of patients, there was an association between a pathological bleeding score and increased prothrombin consumption. This test could be used as an additional indicator of platelet function abnormality liable to be related to bleeding risk.
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Affiliation(s)
- Antoine Babuty
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
| | - Camille Debord
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
| | - Nicolas Drillaud
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
| | - Marion Eveillard
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
| | - Marc Trossaert
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
| | - Catherine Ternisien
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
| | - Marianne Sigaud
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
| | - Emmanuelle Cador
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
| | - Marie C Béné
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
| | - Marc Fouassier
- Nantes Université, CHU Nantes, Service d'Hématologie Biologique, Nantes, France
- Nantes Université, CHU Nantes, Centre de Ressource et de Compétence-Maladies Hémorragiques Constitutionnelles, Nantes, France
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3
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Cuadrado-Payán E, Ramírez-Bajo MJ, Bañón-Maneus E, Rovira J, Diekmann F, Revuelta I, Cucchiari D. Physiopathological role of extracellular vesicles in alloimmunity and kidney transplantation and their use as biomarkers. Front Immunol 2023; 14:1154650. [PMID: 37662919 PMCID: PMC10469977 DOI: 10.3389/fimmu.2023.1154650] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 07/21/2023] [Indexed: 09/05/2023] Open
Abstract
Antibody-mediated rejection is the leading cause of kidney graft dysfunction. The process of diagnosing it requires the performance of an invasive biopsy and subsequent histological examination. Early and sensitive biomarkers of graft damage and alloimmunity are needed to identify graft injury and eventually limit the need for a kidney biopsy. Moreover, other scenarios such as delayed graft function or interstitial fibrosis and tubular atrophy face the same problem. In recent years, interest has grown around extracellular vesicles, specifically exosomes actively secreted by immune cells, which are intercellular communicators and have shown biological significance. This review presents their potential as biomarkers in kidney transplantation and alloimmunity.
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Affiliation(s)
- Elena Cuadrado-Payán
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Barcelona, Spain
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
| | - María José Ramírez-Bajo
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
- Red de Investigación Renal (REDINREN), Insituto de Salud Carlos III, Madrid, Spain
| | - Elisenda Bañón-Maneus
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
- Red de Investigación Renal (REDINREN), Insituto de Salud Carlos III, Madrid, Spain
| | - Jordi Rovira
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
- Red de Investigación Renal (REDINREN), Insituto de Salud Carlos III, Madrid, Spain
| | - Fritz Diekmann
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Barcelona, Spain
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
- Red de Investigación Renal (REDINREN), Insituto de Salud Carlos III, Madrid, Spain
| | - Ignacio Revuelta
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Barcelona, Spain
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
- Red de Investigación Renal (REDINREN), Insituto de Salud Carlos III, Madrid, Spain
| | - David Cucchiari
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Barcelona, Spain
- Laboratori Experimental de Nefrologia I Trasplantament (LENIT), Fundació de Recerca Clínic Barcelona-Institut d’Investigacions Biomèdiques August Pi I Sunyer (FRCB-IDIBAPS), Barcelona, Spain
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4
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García-Villaseñor E, Bojalil-Álvarez L, Murrieta-Álvarez I, Cantero-Fortiz Y, Ruiz-Delgado GJ, Ruiz-Argüelles GJ. Primary Thrombophilia XVI: A Look at the Genotype of the Sticky Platelet Syndrome Phenotype. Clin Appl Thromb Hemost 2021; 27:10760296211044212. [PMID: 34617458 PMCID: PMC8674482 DOI: 10.1177/10760296211044212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The sticky platelet syndrome (SPS) was described by Mammen in 1983. Since then,
scientists in several countries have identified the condition and published
cases or series of patients, thus enabling the description of the prevalence of
the inherited condition, its salient clinical features, and the treatment of the
disease. The diagnosis of the SPS phenotype requires fresh blood samples and
special equipment which is not available in all coagulation laboratories. In the
era of molecular biology, up to now it has not been possible to define a clear
association of the SPS phenotype with a specific molecular marker. Some
molecular changes which have been described in platelet proteins in some persons
with the phenotype of the SPS are here discussed. Nowadays, the SPS phenotype
may be considered as a risk factor for thrombosis and most cases of the SPS
developing vaso-occlussive episodes are the result of its coexistence with other
thrombosis-prone conditions, some of the inherited and some of them acquired,
thus leading to the concept of multifactorial thrombophilia. Ignoring all these
evidence-based concepts is inappropriate, same as stating that the SPS is a
nonentity simply because not all laboratories are endowed with adequate
equipment to support the diagnosis.
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Affiliation(s)
- Elizabeth García-Villaseñor
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,3972Benemérita Universidad Autónoma de Puebla, Puebla, México
| | - Lorena Bojalil-Álvarez
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,27861Universidad Popular Autónoma del Estado de Puebla, Puebla, México
| | - Iván Murrieta-Álvarez
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,27861Universidad Popular Autónoma del Estado de Puebla, Puebla, México
| | - Yahveth Cantero-Fortiz
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,27806Universidad de las Américas Puebla, Puebla, México
| | - Guillermo J Ruiz-Delgado
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,27861Universidad Popular Autónoma del Estado de Puebla, Puebla, México.,56079Laboratorios Clínicos de Puebla, Puebla, México
| | - Guillermo J Ruiz-Argüelles
- Centro de Hematología y Medicina Interna de Puebla, Puebla, México.,27861Universidad Popular Autónoma del Estado de Puebla, Puebla, México.,56079Laboratorios Clínicos de Puebla, Puebla, México
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5
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Aliotta A, Bertaggia Calderara D, Zermatten MG, Marchetti M, Alberio L. Thrombocytopathies: Not Just Aggregation Defects-The Clinical Relevance of Procoagulant Platelets. J Clin Med 2021; 10:jcm10050894. [PMID: 33668091 PMCID: PMC7956450 DOI: 10.3390/jcm10050894] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/31/2021] [Accepted: 02/12/2021] [Indexed: 01/08/2023] Open
Abstract
Platelets are active key players in haemostasis. Qualitative platelet dysfunctions result in thrombocytopathies variously characterized by defects of their adhesive and procoagulant activation endpoints. In this review, we summarize the traditional platelet defects in adhesion, secretion, and aggregation. In addition, we review the current knowledge about procoagulant platelets, focusing on their role in bleeding or thrombotic pathologies and their pharmaceutical modulation. Procoagulant activity is an important feature of platelet activation, which should be specifically evaluated during the investigation of a suspected thrombocytopathy.
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Affiliation(s)
- Alessandro Aliotta
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland; (A.A.); (D.B.C.); (M.G.Z.); (M.M.)
| | - Debora Bertaggia Calderara
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland; (A.A.); (D.B.C.); (M.G.Z.); (M.M.)
| | - Maxime G. Zermatten
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland; (A.A.); (D.B.C.); (M.G.Z.); (M.M.)
| | - Matteo Marchetti
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland; (A.A.); (D.B.C.); (M.G.Z.); (M.M.)
- Service de Médecine Interne, Hôpital de Nyon, CH-1260 Nyon, Switzerland
| | - Lorenzo Alberio
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland; (A.A.); (D.B.C.); (M.G.Z.); (M.M.)
- Correspondence:
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6
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Millington-Burgess SL, Harper MT. Gene of the issue: ANO6 and Scott Syndrome. Platelets 2020; 31:964-967. [PMID: 31746257 DOI: 10.1080/09537104.2019.1693039] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 01/08/2023]
Affiliation(s)
| | - Matthew T Harper
- Department of Pharmacology, University of Cambridge , Cambridge, UK
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7
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Clarke R, Hossain K, Cao K. Physiological roles of transverse lipid asymmetry of animal membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183382. [DOI: 10.1016/j.bbamem.2020.183382] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 06/01/2020] [Accepted: 06/02/2020] [Indexed: 02/07/2023]
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8
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Jung N, Shim YJ. Current Knowledge on Inherited Platelet Function Disorders. CLINICAL PEDIATRIC HEMATOLOGY-ONCOLOGY 2020. [DOI: 10.15264/cpho.2020.27.1.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Nani Jung
- Department of Pediatrics, Keimyung University School of Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea
| | - Ye Jee Shim
- Department of Pediatrics, Keimyung University School of Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea
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9
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Reddy EC, Rand ML. Procoagulant Phosphatidylserine-Exposing Platelets in vitro and in vivo. Front Cardiovasc Med 2020; 7:15. [PMID: 32195268 PMCID: PMC7062866 DOI: 10.3389/fcvm.2020.00015] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/30/2020] [Indexed: 12/11/2022] Open
Abstract
The physiological heterogeneity of platelets leads to diverse responses and the formation of discrete subpopulations upon platelet stimulation. Procoagulant platelets are an example of such subpopulations, a key characteristic of which is exposure either of the anionic aminophospholipid phosphatidylserine (PS) or of tissue factor on the activated platelet surface. This review focuses on the former, in which PS exposure on a subpopulation of platelets facilitates assembly of the intrinsic tenase and prothrombinase complexes, thereby accelerating thrombin generation on the activated platelet surface, contributing importantly to the hemostatic process. Mechanisms involved in platelet PS exposure, and accompanying events, induced by physiologically relevant agonists are considered then contrasted with PS exposure resulting from intrinsic pathway-mediated apoptosis in platelets. Pathologies of PS exposure, both inherited and acquired, are described. A consideration of platelet PS exposure as an antithrombotic target concludes the review.
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Affiliation(s)
- Emily C Reddy
- Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
| | - Margaret L Rand
- Division of Haematology/Oncology, Translational Medicine, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada.,Departments of Laboratory Medicine & Pathobiology, Biochemistry, and Paediatrics, University of Toronto, Toronto, ON, Canada
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10
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Brass LF, Tomaiuolo M, Welsh J, Poventud-Fuentes I, Zhu L, Diamond SL, Stalker TJ. Hemostatic Thrombus Formation in Flowing Blood. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00020-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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11
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Procoagulant platelets: generation, function, and therapeutic targeting in thrombosis. Blood 2017; 130:2171-2179. [DOI: 10.1182/blood-2017-05-787259] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 09/12/2017] [Indexed: 11/20/2022] Open
Abstract
Abstract
Current understanding of how platelets localize coagulation to wound sites has come mainly from studies of a subpopulation of activated platelets. In this review, we summarize data from the last 4 decades that have described these platelets with a range of descriptive titles and attributes. We identify striking overlaps in the reported characteristics of these platelets, which imply a single subpopulation of versatile platelets and thus suggest that their commonality requires unification of their description. We therefore propose the term procoagulant platelet as the unifying terminology. We discuss the agonist requirements and molecular drivers for the dramatic morphological transformation platelets undergo when becoming procoagulant. Finally, we provide perspectives on the biomarker potential of procoagulant platelets for thrombotic events as well as on the possible clinical benefits of inhibitors of carbonic anhydrase enzymes and the water channel Aquaporin-1 for targeting this subpopulation of platelets as antiprocoagulant antithrombotics.
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12
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Abstract
Interest in cell-derived extracellular vesicles and their physiological and pathological implications is constantly growing. Microvesicles, also known as microparticles, are small extracellular vesicles released by cells in response to activation or apoptosis. Among the different microvesicles present in the blood of healthy individuals, platelet-derived microvesicles (PMVs) are the most abundant. Their characterization has revealed a heterogeneous cargo that includes a set of adhesion molecules. Similarly to platelets, PMVs are also involved in thrombosis through support of the coagulation cascade. The levels of circulatory PMVs are altered during several disease manifestations such as coagulation disorders, rheumatoid arthritis, systemic lupus erythematosus, cancers, cardiovascular diseases, and infections, pointing to their potential contribution to disease and their development as a biomarker. This review highlights recent findings in the field of PMV research and addresses their contribution to both healthy and diseased states.
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Affiliation(s)
- Imene Melki
- a Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculty of Medicine , Department of Infectious Diseases and Immunity, Université Laval , Quebec City , QC , Canada
| | - Nicolas Tessandier
- a Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculty of Medicine , Department of Infectious Diseases and Immunity, Université Laval , Quebec City , QC , Canada
| | - Anne Zufferey
- a Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculty of Medicine , Department of Infectious Diseases and Immunity, Université Laval , Quebec City , QC , Canada
| | - Eric Boilard
- a Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculty of Medicine , Department of Infectious Diseases and Immunity, Université Laval , Quebec City , QC , Canada
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13
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Almhanawi BH, Khalid B, Ibrahim TA, Tohit ERM. A transmission electron microscopy study of anticoagulant-induced platelet vesiculation. Porto Biomed J 2016; 2:23-27. [PMID: 32258580 DOI: 10.1016/j.pbj.2016.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 11/19/2016] [Indexed: 11/19/2022] Open
Abstract
Highlights EDTA induces platelet microparticles (PMPs) vesiculation.Sodium citrated tubes are better than EDTA tubes in PMPs analysis.Sodium citrate has a minor impact on platelet structure. Abstract Platelet microparticles (PMPs) are small membrane fragments released from activated platelets in response to various stimuli. PMPs serve as biomarkers for several diseases and conditions and are useful tools for prognostic, diagnostic, and therapeutic purposes. The objective of our study was to compare the direct effects of ethylenediaminetetraacetic acid (EDTA) and sodium citrate anticoagulants on platelet structure and PMP vesiculation using transmission electron microscopy to visualize the morphologic changes in platelets. Micrographs revealed that platelets in the EDTA-anticoagulated tube manifested with significant morphologic changes and induced PMP vesiculation. On the other hand, the sodium citrate-anticoagulated tube showed a normal platelet structure and minor modifications in some cases, with poor indication of PMP vesiculation. In conclusion, EDTA induced platelet activation and PMP vesiculation and represents a major source of artifacts during the pre-analysis steps of PMP vesiculation.
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Affiliation(s)
- Bahaa Hadi Almhanawi
- Department of Pathology, Faculty of Medicine and Health Sciences, University Putra Malaysia, Malaysia
| | - Bahariah Khalid
- Department of Medicine, Faculty of Medicine and Health Sciences, University Putra Malaysia, Malaysia
| | - Tengku Azmi Ibrahim
- Electron Microscopy Unit, Institute of Biomedical Sciences (IBS), University Putra Malaysia, Malaysia
| | - Eusni Rahayu Mohd Tohit
- Department of Pathology, Faculty of Medicine and Health Sciences, University Putra Malaysia, Malaysia
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14
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Hu Y, Kim JH, He K, Wan Q, Kim J, Flach M, Kirchhausen T, Vortkamp A, Winau F. Scramblase TMEM16F terminates T cell receptor signaling to restrict T cell exhaustion. J Exp Med 2016; 213:2759-2772. [PMID: 27810927 PMCID: PMC5110022 DOI: 10.1084/jem.20160612] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/16/2016] [Indexed: 12/21/2022] Open
Abstract
The scramblase TMEM16F is indispensable for the formation of multivesicular bodies in late endosomes that facilitate TCR degradation and signal termination. Hyperactivation of TMEM16F-deficient T cells in chronic LCMV infection leads to severe T cell exhaustion and uncontrolled virus burden. In chronic infection, T cells become hyporesponsive to antigenic stimulation to prevent immunopathology. Here, we show that TMEM16F is required to curb excessive T cell responses in chronic infection with virus. TMEM16F-deficient T cells are hyperactivated during the early phase of infection, exhibiting increased proliferation and cytokine production. Interestingly, this overactivation ultimately leads to severe T cell exhaustion and the inability of the host to control viral burden. Mechanistically, we identify TMEM16F as the dominant lipid scramblase in T lymphocytes that transports phospholipids across membranes. TMEM16F is located in late endosomes, where it facilitates the generation of multivesicular bodies for TCR degradation and signal termination. Consequently, TMEM16F deficiency results in sustained signaling and augmented T cell activation. Our results demonstrate that scramblase restricts TCR responses to avoid overactivation, ensuring a well-balanced immune response in chronic infectious disease.
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Affiliation(s)
- Yu Hu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Ji Hyung Kim
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Kangmin He
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Cell Biology, Harvard Medical School, Boston, MA 02115
| | - Qi Wan
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Jessica Kim
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Melanie Flach
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Tom Kirchhausen
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Cell Biology, Harvard Medical School, Boston, MA 02115
| | - Andrea Vortkamp
- Department of Developmental Biology, University Duisburg-Essen, 45117 Essen, Germany
| | - Florian Winau
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
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French SL, Arthur JF, Lee H, Nesbitt WS, Andrews RK, Gardiner EE, Hamilton JR. Inhibition of protease-activated receptor 4 impairs platelet procoagulant activity during thrombus formation in human blood. J Thromb Haemost 2016; 14:1642-54. [PMID: 26878340 DOI: 10.1111/jth.13293] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 01/26/2016] [Indexed: 01/11/2023]
Abstract
UNLABELLED Essentials The platelet thrombin receptor, PAR4, is an emerging anti-thrombotic drug target. We examined the anti-platelet & anti-thrombotic effects of PAR4 inhibition in human blood. PAR4 inhibition impaired platelet procoagulant activity in isolated cells and during thrombosis. Our study shows PAR4 is required for platelet procoagulant function & thrombosis in human blood. SUMMARY Background Thrombin-induced platelet activation is important for arterial thrombosis. Thrombin activates human platelets predominantly via protease-activated receptor (PAR)1 and PAR4. PAR1 has higher affinity for thrombin, and the first PAR1 antagonist, vorapaxar, was recently approved for use as an antiplatelet agent. However, vorapaxar is contraindicated in a significant number of patients, owing to adverse bleeding events. Consequently, there is renewed interest in the role of platelet PAR4 in the setting of thrombus formation. Objectives To determine the specific antiplatelet effects of inhibiting PAR4 function during thrombus formation in human whole blood. Methods and Results We developed a rabbit polyclonal antibody against the thrombin cleavage site of PAR4, and showed it to be a highly specific inhibitor of PAR4-mediated platelet function. This function-blocking anti-PAR4 antibody was used to probe for PAR4-dependent platelet functions in human isolated platelets in the absence and presence of concomitant PAR1 inhibition. The anti-PAR4 antibody alone was sufficient to abolish the sustained elevation of cytosolic calcium level and consequent phosphatidylserine exposure induced by thrombin, but did not significantly inhibit integrin αII b β3 activation, α-granule secretion, or aggregation. In accord with these in vitro experiments on isolated platelets, selective inhibition of PAR4, but not of PAR1, impaired thrombin activity (fluorescence resonance energy transfer-based thrombin sensor) and fibrin formation (anti-fibrin antibody) in an ex vivo whole blood flow thrombosis assay. Conclusions These findings demonstrate that PAR4 is required for platelet procoagulant function during thrombus formation in human blood, and suggest PAR4 inhibition as a potential target for the prevention of arterial thrombosis.
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Affiliation(s)
- S L French
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - J F Arthur
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - H Lee
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - W S Nesbitt
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
- Microplatforms Research Group, School of Engineering, RMIT University, Melbourne, Australia
| | - R K Andrews
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - E E Gardiner
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - J R Hamilton
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
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Bevers EM, Williamson PL. Getting to the Outer Leaflet: Physiology of Phosphatidylserine Exposure at the Plasma Membrane. Physiol Rev 2016; 96:605-45. [PMID: 26936867 DOI: 10.1152/physrev.00020.2015] [Citation(s) in RCA: 287] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Phosphatidylserine (PS) is a major component of membrane bilayers whose change in distribution between inner and outer leaflets is an important physiological signal. Normally, members of the type IV P-type ATPases spend metabolic energy to create an asymmetric distribution of phospholipids between the two leaflets, with PS confined to the cytoplasmic membrane leaflet. On occasion, membrane enzymes, known as scramblases, are activated to facilitate transbilayer migration of lipids, including PS. Recently, two proteins required for such randomization have been identified: TMEM16F, a scramblase regulated by elevated intracellular Ca(2+), and XKR8, a caspase-sensitive protein required for PS exposure in apoptotic cells. Once exposed at the cell surface, PS regulates biochemical reactions involved in blood coagulation, and bone mineralization, and also regulates a variety of cell-cell interactions. Exposed on the surface of apoptotic cells, PS controls their recognition and engulfment by other cells. This process is exploited by parasites to invade their host, and in specialized form is used to maintain photoreceptors in the eye and modify synaptic connections in the brain. This review discusses what is known about the mechanism of PS exposure at the surface of the plasma membrane of cells, how actors in the extracellular milieu sense surface exposed PS, and how this recognition is translated to downstream consequences of PS exposure.
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Affiliation(s)
- Edouard M Bevers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Department of Biology, Amherst College, Amherst, Massachusetts
| | - Patrick L Williamson
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands; and Department of Biology, Amherst College, Amherst, Massachusetts
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Fujii T, Sakata A, Nishimura S, Eto K, Nagata S. TMEM16F is required for phosphatidylserine exposure and microparticle release in activated mouse platelets. Proc Natl Acad Sci U S A 2015; 112:12800-5. [PMID: 26417084 PMCID: PMC4611630 DOI: 10.1073/pnas.1516594112] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Phosphatidylserine (PtdSer) exposure on the surface of activated platelets requires the action of a phospholipid scramblase(s), and serves as a scaffold for the assembly of the tenase and prothrombinase complexes involved in blood coagulation. Here, we found that the activation of mouse platelets with thrombin/collagen or Ca(2+) ionophore at 20 °C induces PtdSer exposure without compromising plasma membrane integrity. Among five transmembrane protein 16 (TMEM16) members that support Ca(2+)-dependent phospholipid scrambling, TMEM16F was the only one that showed high expression in mouse platelets. Platelets from platelet-specific TMEM16F-deficient mice exhibited defects in activation-induced PtdSer exposure and microparticle shedding, although α-granule and dense granule release remained intact. The rate of tissue factor-induced thrombin generation by TMEM16F-deficient platelets was severely reduced, whereas thrombin-induced clot retraction was unaffected. The imaging of laser-induced thrombus formation in whole animals showed that PtdSer exposure on aggregated platelets was TMEM16F-dependent in vivo. The phenotypes of the platelet-specific TMEM16F-null mice resemble those of patients with Scott syndrome, a mild bleeding disorder, indicating that these mice may provide a useful model for human Scott syndrome.
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Affiliation(s)
- Toshihiro Fujii
- Laboratory of Biochemistry & Immunology, Immunology Frontier Research Center, Osaka University, Osaka 565-0871, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Saitama 332-0012, Japan
| | - Asuka Sakata
- Center for Molecular Medicine, Jichi Medical University, Tochigi 329-0498, Japan
| | - Satoshi Nishimura
- Center for Molecular Medicine, Jichi Medical University, Tochigi 329-0498, Japan; Department of Cardiovascular Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Koji Eto
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, Kyoto 606-8507, Japan
| | - Shigekazu Nagata
- Laboratory of Biochemistry & Immunology, Immunology Frontier Research Center, Osaka University, Osaka 565-0871, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Saitama 332-0012, Japan;
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Hankins HM, Baldridge RD, Xu P, Graham TR. Role of flippases, scramblases and transfer proteins in phosphatidylserine subcellular distribution. Traffic 2014; 16:35-47. [PMID: 25284293 DOI: 10.1111/tra.12233] [Citation(s) in RCA: 194] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 09/29/2014] [Accepted: 09/30/2014] [Indexed: 12/11/2022]
Abstract
It is well known that lipids are heterogeneously distributed throughout the cell. Most lipid species are synthesized in the endoplasmic reticulum (ER) and then distributed to different cellular locations in order to create the distinct membrane compositions observed in eukaryotes. However, the mechanisms by which specific lipid species are trafficked to and maintained in specific areas of the cell are poorly understood and constitute an active area of research. Of particular interest is the distribution of phosphatidylserine (PS), an anionic lipid that is enriched in the cytosolic leaflet of the plasma membrane. PS transport occurs by both vesicular and non-vesicular routes, with members of the oxysterol-binding protein family (Osh6 and Osh7) recently implicated in the latter route. In addition, the flippase activity of P4-ATPases helps build PS membrane asymmetry by preferentially translocating PS to the cytosolic leaflet. This asymmetric PS distribution can be used as a signaling device by the regulated activation of scramblases, which rapidly expose PS on the extracellular leaflet and play important roles in blood clotting and apoptosis. This review will discuss recent advances made in the study of phospholipid flippases, scramblases and PS-specific lipid transfer proteins, as well as how these proteins contribute to subcellular PS distribution.
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Affiliation(s)
- Hannah M Hankins
- Department of Biological Sciences, Vanderbilt University Medical Center, Nashville, TN, 37235, USA
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O'Donnell VB, Murphy RC, Watson SP. Platelet lipidomics: modern day perspective on lipid discovery and characterization in platelets. Circ Res 2014; 114:1185-203. [PMID: 24677238 PMCID: PMC4021279 DOI: 10.1161/circresaha.114.301597] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Lipids are diverse families of biomolecules that perform essential structural and signaling roles in platelets. Their formation and metabolism are tightly controlled by enzymes and signal transduction pathways, and their dysregulation leads to significant defects in platelet function and disease. Platelet activation is associated with significant changes to membrane lipids, and formation of diverse bioactive lipids plays essential roles in hemostasis. In recent years, new generation mass spectrometry analysis of lipids (termed lipidomics) has begun to alter our understanding of how these molecules participate in key cellular processes. Although the application of lipidomics to platelet biology is still in its infancy, seminal earlier studies have shaped our knowledge of how lipids regulate key aspects of platelet biology, including aggregation, shape change, coagulation, and degranulation, as well as how lipids generated by platelets influence other cells, such as leukocytes and the vascular wall, and thus how they regulate hemostasis, vascular integrity, and inflammation, as well as contribute to pathologies, including arterial/deep vein thrombosis and atherosclerosis. This review will provide a brief historical perspective on the characterization of lipids in platelets, then an overview of the new generation lipidomic approaches, their recent application to platelet biology, and future perspectives for research in this area. The major platelet-regulatory lipid families, their formation, metabolism, and their role in health and disease, will be summarized.
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Affiliation(s)
- Valerie B O'Donnell
- From the Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom (V.B.O'D.); Department of Pharmacology, University of Colorado at Denver, Aurora (R.C.M.); and Birmingham Platelet Group, Centre for Cardiovascular Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, Birmingham, United Kingdom (S.P.W.)
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Cox K, Price V, Kahr WHA. Inherited platelet disorders: a clinical approach to diagnosis and management. Expert Rev Hematol 2014; 4:455-72. [DOI: 10.1586/ehm.11.41] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Rao AK. Inherited platelet function disorders: overview and disorders of granules, secretion, and signal transduction. Hematol Oncol Clin North Am 2013; 27:585-611. [PMID: 23714313 DOI: 10.1016/j.hoc.2013.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Inherited disorders of platelet function are characterized by highly variable mucocutaneous bleeding manifestations. The platelet dysfunction arises by diverse mechanisms, including abnormalities in platelet membrane glycoproteins, granules and their contents, platelet signaling and secretion mechanisms: thromboxane production pathways and in platelet procoagulant activities. Platelet aggregation and secretion studies using platelet-rich plasma currently form the primary basis for the diagnosis of an inherited platelet dysfunction. In most such patients, the molecular and genetic mechanisms are unknown. Management of these patients needs to be individualized; therapeutic options include platelet transfusions, 1-desamino-8d-arginine vasopressin (DDAVP), recombinant factor VIIa, and antifibrinolytic agents.
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Affiliation(s)
- A Koneti Rao
- Hematology Section, Department of Medicine and Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA 19140, USA.
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22
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Phosphatidylserine-mediated cellular signaling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 991:177-93. [PMID: 23775696 DOI: 10.1007/978-94-007-6331-9_10] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Phosphatidylserine (PS), a phospholipid with a negatively charged head group, is an important constituent of eukaryotic membranes. Rather than being a passive component of cellular membranes, PS plays an important role in a number of signaling pathways. Signaling is mediated by proteins that are recruited and/or activated by PS in one of two ways: via domains that stereospecifically recognize the head group, or by electrostatic interactions with membranes that are rich in PS and therefore display negative surface charge. Such interactions are key to both intracellular and extracellular signaling cascades. PS, exposed extracellularly, is instrumental in triggering blood clotting and also serves as an "eat me" signal for the clearance of apoptotic cells. Inside the cell, a number of pathways depend of PS; these include kinases, small GTPases and fusogenic proteins. This review will discuss the generation and distribution of PS, current methods of phospholipid visualization within live cells, as well as the current understanding of the role of PS in both extracellular and intracellular signaling events.
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Yang H, Kim A, David T, Palmer D, Jin T, Tien J, Huang F, Cheng T, Coughlin SR, Jan YN, Jan LY. TMEM16F forms a Ca2+-activated cation channel required for lipid scrambling in platelets during blood coagulation. Cell 2012; 151:111-22. [PMID: 23021219 DOI: 10.1016/j.cell.2012.07.036] [Citation(s) in RCA: 327] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 06/12/2012] [Accepted: 07/05/2012] [Indexed: 01/15/2023]
Abstract
Collapse of membrane lipid asymmetry is a hallmark of blood coagulation. TMEM16F of the TMEM16 family that includes TMEM16A/B Ca(2+)-activated Cl(-) channels (CaCCs) is linked to Scott syndrome with deficient Ca(2+)-dependent lipid scrambling. We generated TMEM16F knockout mice that exhibit bleeding defects and protection in an arterial thrombosis model associated with platelet deficiency in Ca(2+)-dependent phosphatidylserine exposure and procoagulant activity and lack a Ca(2+)-activated cation current in the platelet precursor megakaryocytes. Heterologous expression of TMEM16F generates a small-conductance Ca(2+)-activated nonselective cation (SCAN) current with subpicosiemens single-channel conductance rather than a CaCC. TMEM16F-SCAN channels permeate both monovalent and divalent cations, including Ca(2+), and exhibit synergistic gating by Ca(2+) and voltage. We further pinpointed a residue in the putative pore region important for the cation versus anion selectivity of TMEM16F-SCAN and TMEM16A-CaCC channels. This study thus identifies a Ca(2+)-activated channel permeable to Ca(2+) and critical for Ca(2+)-dependent scramblase activity during blood coagulation. PAPERFLICK:
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Affiliation(s)
- Huanghe Yang
- Department of Physiology, Howard Hughes Medical Institute, University of California, San Francisco, 94143, USA
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27
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Jandrey KE, Norris JW, Tucker M, Brooks MB. Clinical characterization of canine platelet procoagulant deficiency (Scott syndrome). J Vet Intern Med 2012; 26:1402-7. [PMID: 23061683 DOI: 10.1111/j.1939-1676.2012.01012.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 06/26/2012] [Accepted: 08/28/2012] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Platelet function defects are rare causes of bleeding diatheses; however, disease prevalence might be underestimated because diagnosis requires assessment of specific parameters of platelet activation. OBJECTIVES The goal of this study was to characterize the clinical presentation of canine Scott syndrome (CSS), an intrinsic platelet function defect first identified in a closed colony of German Shepherds (GSD). ANIMALS Eleven (n = 6 female) client-owned GSD affected with CSS that sought veterinary care for one or more episodes of abnormal bleeding. METHODS Retrospective review of all cases of CSS diagnosed through the Comparative Coagulation Laboratory at Cornell University between 2005 and 2011. The diagnosis of CSS was based on 2 measures of platelet procoagulant activity: serum prothrombin consumption and flow cytometric detection of platelet phosphatidylserine externalization after in vitro activation. RESULTS Postoperative hemorrhage was the most common sign of CSS, whereas petechiae were not found in any dog. Although most GSD responded to platelet transfusion, refractory epistaxis in 2 GSD was managed by nasal arterial embolization. The CSS trait was not restricted to a single pedigree of related GSD or to a single geographic region. CONCLUSIONS AND CLINICAL IMPORTANCE Unlike thrombocytopenia and platelet aggregation defects, petechiae and other capillary hemorrhage are not typical features of CSS. After preliminary screening to rule out more common causes of hemorrhage, CSS should be considered in the differential diagnosis of recurrent hemorrhage in GSD, and potentially other breeds of dog. Definitive diagnosis of CSS requires specific tests of platelet procoagulant activity.
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Affiliation(s)
- K E Jandrey
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
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Goggs R, Poole AW. Platelet signaling-a primer. J Vet Emerg Crit Care (San Antonio) 2012; 22:5-29. [PMID: 22316389 DOI: 10.1111/j.1476-4431.2011.00704.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 11/25/2011] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To review the receptors and signal transduction pathways involved in platelet plug formation and to highlight links between platelets, leukocytes, endothelium, and the coagulation system. DATA SOURCES Original studies, review articles, and book chapters in the human and veterinary medical fields. DATA SYNTHESIS Platelets express numerous surface receptors. Critical among these are glycoprotein VI, the glycoprotein Ib-IX-V complex, integrin α(IIb) β(3) , and the G-protein-coupled receptors for thrombin, ADP, and thromboxane. Activation of these receptors leads to various important functional events, in particular activation of the principal adhesion receptor α(IIb) β(3) . Integrin activation allows binding of ligands such as fibrinogen, mediating platelet-platelet interaction in the process of aggregation. Signals activated by these receptors also couple to 3 other important functional events, secretion of granule contents, change in cell shape through cytoskeletal rearrangement, and procoagulant membrane expression. These processes generate a stable thrombus to limit blood loss and promote restoration of endothelial integrity. CONCLUSIONS Improvements in our understanding of how platelets operate through their signaling networks are critical for diagnosis of unusual primary hemostatic disorders and for rational antithrombotic drug design.
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Affiliation(s)
- Robert Goggs
- School of Physiology and Pharmacology, Faculty of Medical and Veterinary Sciences, University of Bristol, UK.
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Aspirin: pharmacology and clinical applications. THROMBOSIS 2011; 2012:173124. [PMID: 22195279 PMCID: PMC3236360 DOI: 10.1155/2012/173124] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 10/03/2011] [Indexed: 12/21/2022]
Abstract
Antiplatelet therapy has been documented to reduce risks of cardiovascular disease after acute myocardial infarction, coronary artery bypass graft, and in chronic atrial fibrillation patients, amongst other risk factors. Conventional management of thrombosis-based disorders includes the use of heparin, oral anticoagulants, and the preferred antiplatelet agent aspirin. Interestingly, aspirin was not intended to be used as an antiplatelet agent; rather, after being repurposed, it has become one of the most widely prescribed antithrombotic drugs. To this end, there have been several milestones in the development of antiplatelet agents in the last few decades, such as adenosine diphosphate receptor inhibitors, phosphodiesterase inhibitors, and GPIIb/IIIa inhibitors. However, given some of the limitations of these therapies, aspirin continues to play a major role in the management of thrombotic and cardiovascular disorders and is expected to do so for years to come.
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Abstract
The formation of blood clots--thrombosis--at sites of atherosclerotic plaque rupture is a major clinical problem despite ongoing improvements in antithrombotic therapy. Progress in identifying the pathogenic mechanisms regulating arterial thrombosis has led to the development of newer therapeutics, and there is general anticipation that these treatments will have greater efficacy and improved safety. However, major advances in this field require the identification of specific risk factors for arterial thrombosis in affected individuals and a rethink of the 'one size fits all' approach to antithrombotic therapy.
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Affiliation(s)
- Shaun P Jackson
- Australian Centre for Blood Diseases, Alfred Medical Research and Education Precinct, Monash University, Melbourne, Australia.
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Zahra S, Anderson J, Stirling D, Ludlam C. Plasma microparticles are not elevated in fresh plasma from patients with gynaecological malignancy — An observational study. Gynecol Oncol 2011; 123:152-6. [DOI: 10.1016/j.ygyno.2011.06.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 06/27/2011] [Accepted: 06/30/2011] [Indexed: 01/01/2023]
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Lhermusier T, Chap H, Payrastre B. Platelet membrane phospholipid asymmetry: from the characterization of a scramblase activity to the identification of an essential protein mutated in Scott syndrome. J Thromb Haemost 2011; 9:1883-91. [PMID: 21958383 DOI: 10.1111/j.1538-7836.2011.04478.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Like all eukaryotic cells, platelets maintain plasma membrane phospholipid asymmetry in normal blood circulation via lipid transporters, which control transbilayer movement. Upon platelet activation, the asymmetric orientation of membrane phospholipids is rapidly disrupted, resulting in a calcium-dependent exposure of the anionic phospholipid, phosphatidylserine (PS), at the outer platelet surface. This newly-exposed PS surface is a major component of normal hemostasis because it supports platelet procoagulant function. Binding of blood clotting enzyme complexes to this negatively-charged membrane surface allows a dramatic increase in the rate of conversion of zymogens to active serine proteases, which in turn produce a burst of thrombin leading to the formation of a fibrin clot and further platelet activation. Cells have the capacity to catalyze transbilayer phospholipid exchange via ATP-requiring translocase enzymes (flippases and floppases), which control unidirectional phospholipid transport against a concentration gradient. They also use an energy-independent, calcium-dependent scramblase activity to govern the bidirectional exchange of phospholipids between the two leaflets of the bilayer; this activity is essential for PS exposure during platelet activation. Scramblase activity, biochemically characterized in the 1980s, is deficient in patients with Scott syndrome, a rare inherited bleeding disorder with defective platelet procoagulant activity. Despite considerable efforts, the platelet scramblase protein remained elusive for years but a significant advance has recently been made with the identification of TMEM16F, a membrane protein essential for calcium-dependent PS exposure whose loss of function mutations are found in Scott syndrome. This review recalls historical aspects of platelet membrane asymmetry characterization, summarizes the mechanisms and roles of PS exposure following platelet activation and discusses the recent identification of TMEM16F and its significance in the scrambling process.
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Affiliation(s)
- T Lhermusier
- Inserm, U1048 and Université Toulouse 3, I2MC, 31432 Toulouse Cedex 04, France
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Morel O, Morel N, Jesel L, Freyssinet JM, Toti F. Microparticles: a critical component in the nexus between inflammation, immunity, and thrombosis. Semin Immunopathol 2011; 33:469-86. [DOI: 10.1007/s00281-010-0239-3] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Accepted: 12/20/2010] [Indexed: 12/27/2022]
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Abstract
Platelets are a remarkable mammalian adaptation that are required for human survival by virtue of their ability to prevent and arrest bleeding. Ironically, however, in the past century, the platelets' hemostatic activity became maladaptive for the increasingly large percentage of individuals who develop age-dependent progressive atherosclerosis. As a result, platelets also make a major contribution to ischemic thrombotic vascular disease, the leading cause of death worldwide. In this brief review, I provide historical descriptions of a highly selected group of topics to provide a framework for understanding our current knowledge and the trends that are likely to continue into the future of platelet research. For convenience, I separate the eras of platelet research into the "Descriptive Period" extending from ~1880-1960 and the "Mechanistic Period" encompassing the past ~50 years since 1960. We currently are reaching yet another inflection point, as there is a major shift from a focus on traditional biochemistry and cell and molecular biology to an era of single molecule biophysics, single cell biology, single cell molecular biology, structural biology, computational simulations, and the high-throughput, data-dense techniques collectively named with the "omics postfix". Given the progress made in understanding, diagnosing, and treating many rare and common platelet disorders during the past 50 years, I think it appropriate to consider it a Golden Age of Platelet Research and to recognize all of the investigators who have made important contributions to this remarkable achievement..
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Affiliation(s)
- Barry S. Coller
- Laboratory of Blood and Vascular Biology, Rockefeller University, 1230 York Avenue, New York, NY 10065, Tel: 212-327-7490, Fax: 212-327-7493
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36
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Microparticles in newborn cord blood: Slight elevation after normal delivery. Thromb Res 2011; 128:62-7. [DOI: 10.1016/j.thromres.2011.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 12/28/2010] [Accepted: 01/31/2011] [Indexed: 11/18/2022]
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37
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Morel O, Jesel L, Freyssinet JM, Toti F. Cellular mechanisms underlying the formation of circulating microparticles. Arterioscler Thromb Vasc Biol 2011; 31:15-26. [PMID: 21160064 DOI: 10.1161/atvbaha.109.200956] [Citation(s) in RCA: 388] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Microparticles (MPs) derived from platelets, monocytes, endothelial cells, red blood cells, and granulocytes may be detected in low concentrations in normal plasma and at increased levels in atherothrombotic cardiovascular diseases. The elucidation of the cellular mechanisms underlying the generation of circulating MPs is crucial for improving our understanding of their pathophysiological role in health and disease. The flopping of phosphatidylserine (PS) to the outer leaflet of the plasma membrane is the key event that will ultimately lead to the shedding of procoagulant MPs from activated or apoptotic cells. Research over the last few years has revealed important roles for calcium-, mitochondrial-, and caspase-dependent mechanisms leading to PS exposure. The study of Scott cells has unraveled different molecular mechanisms that may contribute to fine-tuning of PS exposure and MP release in response to a variety of specific stimuli. The pharmacological modulation of MP release may have a substantial therapeutic impact in the management of atherothrombotic vascular disorders. Because PS exposure is a key feature in pathological processes different from hemostasis and thrombosis, the most important obstacle in the field of MP-modulating drugs seems to be carefully targeting MP release to relevant cell types at an optimal level, so as to achieve a beneficial action and limit possible adverse effects.
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Affiliation(s)
- Olivier Morel
- Institut d'Hématologie & Immunologie, Université de Strasbourg, Strasbourg, France
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38
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Kaplan ZS, Jackson SP. The role of platelets in atherothrombosis. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2011; 2011:51-61. [PMID: 22160012 DOI: 10.1182/asheducation-2011.1.51] [Citation(s) in RCA: 172] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Platelets have evolved highly specialized adhesion mechanisms that enable cell-matrix and cell-cell interactions throughout the entire vasculature irrespective of the prevailing hemodynamic conditions. This unique property of platelets is critical for their ability to arrest bleeding and promote vessel repair. Platelet adhesion under conditions of high shear stress, as occurs in stenotic atherosclerotic arteries, is central to the development of arterial thrombosis; therefore, precise control of platelet adhesion must occur to maintain blood fluidity and to prevent thrombotic or hemorrhagic complications. Whereas the central role of platelets in hemostasis and thrombosis has long been recognized and well defined, there is now a major body of evidence supporting an important proinflammatory function for platelets that is linked to host defense and a variety of autoimmune and inflammatory diseases. In the context of the vasculature, experimental evidence indicates that the proinflammatory function of platelets can regulate various aspects of the atherosclerotic process, including its initiation and propagation. The mechanisms underlying the proatherogenic function of platelets are increasingly well defined and involve specific adhesive interactions between platelets and endothelial cells at atherosclerotic-prone sites, leading to the enhanced recruitment and activation of leukocytes. Through the release of chemokines, proinflammatory molecules, and other biological response modulators, the interaction among platelets, endothelial cells, and leukocytes establishes a localized inflammatory response that accelerates atherosclerosis. These inflammatory processes typically occur in regions of the vasculature experiencing low shear and perturbed blood flow, a permissive environment for leukocyte-platelet and leukocyte-endothelial interactions. Therefore, the concept has emerged that platelets are a central element of the atherothrombotic process and that future therapeutic strategies to combat this disease need to take into consideration both the prothrombotic and proinflammatory function of platelets.
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Affiliation(s)
- Zane S Kaplan
- Australian Centre for Blood Diseases, Alfred Medical Research and Education Precinct, Monash University, Melbourne, Australia
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Satta N, Toti F, Fressinaud E, Meyer D, Freyssinet JM. Scott syndrome: an inherited defect of the procoagulant activity of platelets. Platelets 2010; 8:117-24. [DOI: 10.1080/09537109709169326] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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40
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Bevers EM, Williamson PL. Phospholipid scramblase: An update. FEBS Lett 2010; 584:2724-30. [DOI: 10.1016/j.febslet.2010.03.020] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 03/12/2010] [Accepted: 03/12/2010] [Indexed: 10/19/2022]
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41
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Thomas CP, Morgan LT, Maskrey BH, Murphy RC, Kühn H, Hazen SL, Goodall AH, Hamali HA, Collins PW, O'Donnell VB. Phospholipid-esterified eicosanoids are generated in agonist-activated human platelets and enhance tissue factor-dependent thrombin generation. J Biol Chem 2010; 285:6891-903. [PMID: 20061396 PMCID: PMC2844139 DOI: 10.1074/jbc.m109.078428] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Here, a group of specific lipids, comprising phosphatidylethanolamine (PE)- or phosphatidylcholine (PC)-esterified 12S-hydroxyeicosatetraenoic acid (12S-HETE), generated by 12-lipoxygenase was identified and characterized. 12S-HETE-PE/PCs were formed within 5 min of activation by thrombin, ionophore, or collagen. Esterified HETE levels generated in response to thrombin were 5.85 ± 1.42 (PE) or 18.35 ± 4.61 (PC), whereas free was 65.5 ± 17.6 ng/4 × 107 cells (n = 5 separate donors, mean ± S.E.). Their generation was stimulated by triggering protease-activated receptors-1 and -4 and signaling via Ca2+ mobilization secretory phospholipase A2, platelet-activating factor-acetylhydrolase, src tyrosine kinases, and protein kinase C. Stable isotope labeling showed that they form predominantly by esterification that occurs on the same time scale as free acid generation. Unlike free 12S-HETE that is secreted, esterified HETEs remain cell-associated, with HETE-PEs migrating to the outside of the plasma membrane. 12-Lipoxygenase inhibition attenuated externalization of native PE and phosphatidylserine and HETE-PEs. Platelets from a patient with the bleeding disorder, Scott syndrome, did not externalize HETE-PEs, and liposomes supplemented with HETE-PC dose-dependently enhanced tissue factor-dependent thrombin generation in vitro. This suggests a role for these novel lipids in promoting coagulation. Thus, oxidized phospholipids form by receptor/agonist mechanisms, not merely as an undesirable consequence of vascular and inflammatory disease.
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Fadeel B, Xue D. The ins and outs of phospholipid asymmetry in the plasma membrane: roles in health and disease. Crit Rev Biochem Mol Biol 2009; 44:264-77. [PMID: 19780638 DOI: 10.1080/10409230903193307] [Citation(s) in RCA: 288] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A common feature of all eukaryotic membranes is the non-random distribution of different lipid species in the lipid bilayer (lipid asymmetry). Lipid asymmetry provides the two sides of the plasma membrane with different biophysical properties and influences numerous cellular functions. Alteration of lipid asymmetry plays a prominent role during cell fusion, activation of the coagulation cascade, and recognition and removal of apoptotic cell corpses by macrophages (programmed cell clearance). Here we discuss the origin and maintenance of phospholipid asymmetry, based on recent studies in mammalian systems as well as in Caenhorhabditis elegans and other model organisms, along with emerging evidence for a conserved role of mitochondria in the loss of lipid asymmetry during apoptosis. The functional significance of lipid asymmetry and its disruption during health and disease is also discussed.
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Affiliation(s)
- Bengt Fadeel
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
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Abstract
The intracellular Ca(2+) concentration of many nonexcitable cells is regulated by calcium store release and store-operated calcium entry (SOCE). In platelets, STIM1 was recently identified as the main calcium sensor expressed in the endoplasmic reticulum. To evaluate the role of the SOC channel moiety, Orai1, in platelet SOCE, we generated mice expressing a mutated, inactive form of Orai1 in blood cells only (Orai1(R93W)). Platelets expressing Orai1(R93W) were characterized by markedly reduced SOCE and impaired agonist-induced increases in [Ca(2+)](i). Orai1(R93W) platelets showed reduced integrin activation and impaired degranulation when stimulated with low agonist concentrations under static conditions. This defect, however, did not significantly affect the ability of Orai1(R93W) platelets to aggregate or to adhere to collagen under arterial flow conditions ex vivo. In contrast, these adherent Orai1(R93W) platelets were defective in surface phosphatidylserine exposure, suggesting that Orai1 is crucial for the platelets' procoagulant response rather than for other Ca(2+)-dependent cellular responses.
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Brooks MB, Catalfamo JL, Etter K, Brisbin A, Bustamante CD. Exclusion of ABCA-1 as a candidate gene for canine Scott syndrome. J Thromb Haemost 2008; 6:1608-10. [PMID: 18844827 PMCID: PMC2766810 DOI: 10.1111/j.1538-7836.2008.03068.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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47
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Salles II, Feys HB, Iserbyt BF, De Meyer SF, Vanhoorelbeke K, Deckmyn H. Inherited traits affecting platelet function. Blood Rev 2008; 22:155-72. [DOI: 10.1016/j.blre.2007.11.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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48
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Bilateral vitreous hemorrhage in a child due to isolated platelet factor 3 availability defect. J AAPOS 2008; 12:203-4. [PMID: 18423342 DOI: 10.1016/j.jaapos.2007.09.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 09/21/2007] [Accepted: 09/23/2007] [Indexed: 11/20/2022]
Abstract
Vitreous hemorrhage is an uncommon cause of decreased vision in children. We report a 3-year-old child with bilateral vitreous hemorrhage secondary to an isolated platelet factor 3 (PF-3) availability defect. Prophylactic infusion of platelet-rich plasma followed by pars plana vitrectomy in both eyes resulted in an excellent surgical and visual outcome. This report emphasizes the importance of exhaustive hematological and platelet function studies in a child presenting with bilateral vitreous hemorrhage and its implications on the management of present and future bleeding episodes.
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Nomura S, Ozaki Y, Ikeda Y. Function and role of microparticles in various clinical settings. Thromb Res 2008; 123:8-23. [DOI: 10.1016/j.thromres.2008.06.006] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2008] [Revised: 05/16/2008] [Accepted: 06/09/2008] [Indexed: 12/18/2022]
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50
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Toth B, Lok CAR, Böing A, Diamant M, van der Post JAM, Friese K, Nieuwland R. Microparticles and exosomes: impact on normal and complicated pregnancy. Am J Reprod Immunol 2007; 58:389-402. [PMID: 17922691 DOI: 10.1111/j.1600-0897.2007.00532.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Eukaryotic cells release vesicles into their environment by membrane shedding (ectosomes or microparticles) and secretion (exosomes). Microparticles and exosomes occur commonly in vitro and in vivo. The occurrence, composition and function(s) of these vesicles change during disease (progression). During the last decade, the scientific and clinical interest increased tremendously. Evidence is accumulating that microparticles and exosomes may be of pathophysiological relevance in autoimmune, cardiovascular and thromboembolic diseases, as well as inflammatory and infectious disorders. In this review, we will summarize the discovery, biology, structure and function of microparticles and exosomes, and discuss their (patho-) physiological role during normal and complicated pregnancy.
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Affiliation(s)
- Bettina Toth
- Department of Obstetrics and Gynaecology, Ludwig-Maximilians University, Grosshadern, Munich, Germany.
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