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Ye Y, Leng M, Chai S, Yang L, Ren L, Wan W, Wang H, Li L, Li C, Meng Z. Antiplatelet effects of the CEACAM1-derived peptide QDTT. Platelets 2024; 35:2308635. [PMID: 38345065 DOI: 10.1080/09537104.2024.2308635] [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: 08/29/2023] [Accepted: 01/17/2024] [Indexed: 02/15/2024]
Abstract
Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) restricts platelet activation via platelet collagen receptor GPVI/FcRγ-chain. In this study, screening against collagen-induced platelet aggregation was performed to identify functional CEACAM1 extracellular domain fragments. CEACAM1 fragments, including Ala-substituted peptides, were synthesized. Platelet assays were conducted on healthy donor samples for aggregation, cytotoxicity, adhesion, spreading, and secretion. Mice were used for tail bleeding and FeCl3-induced thrombosis experiments. Clot retraction was assessed using platelet-rich plasma. Extracellular segments of CEACAM1 and A1 domain-derived peptide QDTT were identified, while N, A2, and B domains showed no involvement. QDTT inhibited platelet aggregation. Ala substitution for essential amino acids (Asp139, Thr141, Tyr142, Trp144, and Trp145) in the QDTT sequence abrogated collagen-induced aggregation inhibition. QDTT also suppressed platelet secretion and "inside-out" GP IIb/IIIa activation by convulxin, along with inhibiting PI3K/Akt pathways. QDTT curtailed FeCl3-induced mesenteric thrombosis without significantly prolonging bleeding time, implying the potential of CEACAM1 A1 domain against platelet activation without raising bleeding risk, thus paving the way for novel antiplatelet drugs.
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Affiliation(s)
- Yujia Ye
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Min Leng
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Shengjie Chai
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Lihong Yang
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Longcheng Ren
- Cardiovascular Department, Tengchong Hospital of Traditional Chinese Medicine, Tengchong, PR China
| | - Wen Wan
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Huawei Wang
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Longjun Li
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Chaozhong Li
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
| | - Zhaohui Meng
- Laboratory of Molecular Cardiology, Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, PR China
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Badejo PO, Umphres SS, Ali HEA, Alarabi AB, Qadri S, Alshbool FZ, Khasawneh FT. Exposure to Electronic Waterpipes Increases the Risk of Occlusive Cardiovascular Disease in C57BL/6J Mice. J Cardiovasc Pharmacol Ther 2024; 29:10742484241242702. [PMID: 38592084 DOI: 10.1177/10742484241242702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
INTRODUCTION It is well documented that cardiovascular disease (CVD) is the leading cause of death in the US and worldwide, with smoking being the most preventable cause. Additionally, most smokers die from thrombotic-based diseases, in which platelets play a major role. To this end, because of the proven harm of smoking, several novel tobacco products such as electronic(e)-waterpipe have been gaining popularity among different sectors of the population, partly due to their "false" safety claims. While many investigators have focused on the negative health effects of traditional cigarettes and e-cigarettes on the cardiovascular system, virtually little or nothing is known about e-waterpipes, which we investigated herein. METHODS AND MATERIALS To investigate their occlusive CVD effects, we employed a whole-body mouse exposure model of e-waterpipe vape/smoke and exposed C57BL/6J male mice (starting at 7 weeks of age) for 1 month, with the controls exposed to clean air. Exposures took place seven times a week, according to the well-known Beirut protocol, which has been employed in many studies, as it mimics real-life waterpipe exposure scenarios; specifically, 171 puffs of 530 ml volume of the e-liquid at 2.6 s puff duration and 17 s puff interval. RESULTS The e-waterpipe exposed mice had shortened bleeding and occlusion times, when compared to the clean air controls, indicating a prothrombotic phenotype. As for the mechanism underlying this phenotype, we found that e-waterpipe exposed platelets exhibited enhanced agonist-triggered aggregation and dense granule secretion. Also, flow cytometry analysis of surface markers of platelet activation showed that both P-selectin and integrin GPIIb-IIIa activation were enhanced in the e-waterpipe exposed platelets, relative to the controls. Finally, platelet spreading and Akt phosphorylation were also more pronounced in the exposed mice. CONCLUSION We document that e-waterpipe exposure does exert untoward effects in the context of thrombosis-based CVD, in part, via promoting platelet hyperreactivity.
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Affiliation(s)
- Precious O Badejo
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Shelby S Umphres
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Hamdy E A Ali
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Ahmed B Alarabi
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Shahnaz Qadri
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Fatima Z Alshbool
- Department of Pharmacy Practice, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
| | - Fadi T Khasawneh
- Department of Pharmaceutical Sciences, Irma Lerma Rangel School of Pharmacy, Texas A&M University, Kingsville, TX, USA
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3
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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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4
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Cheung HYF, Zou J, Tantiwong C, Fernandez DI, Huang J, Ahrends R, Roest M, Cavill R, Gibbins J, Heemskerk JWM. High-throughput assessment identifying major platelet Ca 2+ entry pathways via tyrosine kinase-linked and G protein-coupled receptors. Cell Calcium 2023; 112:102738. [PMID: 37060673 DOI: 10.1016/j.ceca.2023.102738] [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: 12/01/2022] [Revised: 03/04/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023]
Abstract
In platelets, elevated cytosolic Ca2+ is a crucial second messenger, involved in most functional responses, including shape change, secretion, aggregation and procoagulant activity. The platelet Ca2+ response consists of Ca2+ mobilization from endoplasmic reticulum stores, complemented with store-operated or receptor-operated Ca2+ entry pathways. Several channels can contribute to the Ca2+ entry, but their relative contribution is unclear upon stimulation of ITAM-linked receptors such as glycoprotein VI (GPVI) and G-protein coupled receptors such as the protease-activated receptors (PAR) for thrombin. We employed a 96-well plate high-throughput assay with Fura-2-loaded human platelets to perform parallel [Ca2+]i measurements in the presence of EGTA or CaCl2. Per agonist condition, this resulted in sets of EGTA, CaCl2 and Ca2+ entry ratio curves, defined by six parameters, reflecting different Ca2+ ion fluxes. We report that threshold stimulation of GPVI or PAR, with a variable contribution of secondary mediators, induces a maximal Ca2+ entry ratio of 3-7. Strikingly, in combination with Ca2+-ATPase inhibition by thapsigargin, the maximal Ca2+ entry ratio increased to 400 (GPVI) or 40 (PAR), pointing to a strong receptor-dependent enhancement of store-operated Ca2+ entry. By pharmacological blockage of specific Ca2+ channels in platelets, we found that, regardless of GPVI or PAR stimulation, the Ca2+ entry ratio was strongest affected by inhibition of ORAI1 (2-APB, Synta66) > Na+/Ca2+ exchange (NCE) > P2×1 (only initial). In contrast, inhibition of TRPC6, Piezo1/2 or STIM1 was without effect. Together, these data reveal ORAI1 and NCE as dominating Ca2+ carriers regulating GPVI- and PAR-induced Ca2+ entry in human platelets.
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Affiliation(s)
- Hilaire Yam Fung Cheung
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V, Dortmund, Germany; Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jinmi Zou
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Synapse Research Institute Maastricht, 6217 KD Maastricht, The Netherlands
| | - Chukiat Tantiwong
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Institute for Cardiovascular and Metabolic Research (ICMR), School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Delia I Fernandez
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela, Santiago de Compostela, 15706, Spain
| | - Jingnan Huang
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V, Dortmund, Germany; Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela, Santiago de Compostela, 15706, Spain
| | - Robert Ahrends
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V, Dortmund, Germany; Dept. of Analytical Chemistry, University of Vienna, Vienna, Austria
| | - Mark Roest
- Synapse Research Institute Maastricht, 6217 KD Maastricht, The Netherlands
| | - Rachel Cavill
- Department of Advanced Computing Sciences, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Jon Gibbins
- Institute for Cardiovascular and Metabolic Research (ICMR), School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands; Synapse Research Institute Maastricht, 6217 KD Maastricht, The Netherlands.
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A Novel Antibody Targeting the Second Extracellular Loop of the Serotonin 5-HT2A Receptor Inhibits Platelet Function. Int J Mol Sci 2022; 23:ijms23158794. [PMID: 35955928 PMCID: PMC9369033 DOI: 10.3390/ijms23158794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/02/2022] [Accepted: 08/02/2022] [Indexed: 11/17/2022] Open
Abstract
Serotonin (5-hydroxytriptamine or 5-HT) is known to be a weak platelet agonist, and is involved in thrombus formation. While 5-HT cannot induce platelet aggregation on its own, when secreted from the alpha granules, it binds to its G-protein Coupled Receptor (GPCR; i.e., 5HT2AR), thereby acting to amplify platelet functional responses (e.g., aggregation). Thus, 5HT2AR-mediated responses are more involved in the secondary amplification of platelet aggregation in the growing thrombus. Therefore, even though 5-HT can be seen as a weak inducer of platelet activation, it is an important amplifier of aggregation triggered by agonists such as ADP, collagen, and epinephrine, thereby enhancing thrombogenesis. The 5HT2AR/5HT2A signaling pathway is of clinical interest to the scientific and medical communities as it has been implicated in the genesis of several forms of cardiovascular disorders. However, efforts to develop antagonists for 5HT2AR as therapeutic agents in cardiovascular diseases have thus far failed due to these reagents having deleterious side-effects, and/or to lack of selectivity, amongst other reasons. In light of research efforts that identified that the 5HT2AR ligand binding domain resides in the second extracellular loop (EL2; amino acids P209-N233), we developed an antibody, i.e., referred to as 5HT2ARAb, against the EL2 region, and characterized its pharmacological activity in the context of platelets. Thus, we utilized platelets from healthy human donors, as well as C57BL/6J mice (10-12 weeks old) to analyze the inhibitory effects of the 5HT2ARAb on platelet activation in vitro, ex vivo, and on thrombogenesis in vivo as well as on 5HT2AR ligand binding. Our results indicate that the 5HT2ARAb inhibits 5-HT-enhanced platelet activation in vitro and ex vivo, but has no apparent effects on that which is agonist-induced. The 5HT2ARAb was also found to prolong the thrombus occlusion time, and it did so without modulating the tail bleeding time, in mice unlike the P2Y12 antagonist clopidogrel and the 5HT2AR antagonist ketanserin. Moreover, it was found that the 5HT2ARAb does so by directly antagonizing the platelet 5HT2AR. Our findings document that the custom-made 5HT2ARAb exhibits platelet function blocking activity and protects against thrombogenesis without impairing normal hemostasis.
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6
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Ali HA, Alarabi AB, Karim ZA, Rodriguez V, Hernandez KR, Lozano PA, El-Halawany MS, Alshbool FZ, Khasawneh FT. In utero thirdhand smoke exposure modulates platelet function in a sex-dependent manner. Haematologica 2021; 107:312-315. [PMID: 34525795 PMCID: PMC8719073 DOI: 10.3324/haematol.2021.279388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Indexed: 11/24/2022] Open
Affiliation(s)
- Hamdy A Ali
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX
| | - Ahmed B Alarabi
- Department of Pharmacy Practice, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX
| | - Zubair A Karim
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El- Paso, El Paso, TX
| | - Victor Rodriguez
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El- Paso, El Paso, TX
| | - Keziah R Hernandez
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El- Paso, El Paso, TX
| | - Patricia A Lozano
- Department of Pharmacy Practice, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX
| | - Medhat S El-Halawany
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX
| | - Fatima Z Alshbool
- Department of Pharmacy Practice, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX
| | - Fadi T Khasawneh
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy Texas A/M University, Kingsville, TX.
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7
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Dickhout A, Tullemans BME, Heemskerk JWM, Thijssen VLJL, Kuijpers MJE, Koenen RR. Galectin-1 and platelet factor 4 (CXCL4) induce complementary platelet responses in vitro. PLoS One 2021; 16:e0244736. [PMID: 33411760 PMCID: PMC7790394 DOI: 10.1371/journal.pone.0244736] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 12/15/2020] [Indexed: 12/26/2022] Open
Abstract
Galectin-1 (gal-1) is a carbohydrate-binding lectin with important functions in angiogenesis, immune response, hemostasis and inflammation. Comparable functions are exerted by platelet factor 4 (CXCL4), a chemokine stored in the α-granules of platelets. Previously, gal-1 was found to activate platelets through integrin αIIbβ3. Both gal-1 and CXCL4 have high affinities for polysaccharides, and thus may mutually influence their functions. The aim of this study was to investigate a possible synergism of gal-1 and CXCL4 in platelet activation. Platelets were treated with increasing concentrations of gal-1, CXCL4 or both, and aggregation, integrin activation, P-selectin and phosphatidyl serine (PS) exposure were determined by light transmission aggregometry and by flow cytometry. To investigate the influence of cell surface sialic acid, platelets were treated with neuraminidase prior to stimulation. Gal-1 and CXCL4 were found to colocalize on the platelet surface. Stimulation with gal-1 led to integrin αIIbβ3 activation and to robust platelet aggregation, while CXCL4 weakly triggered aggregation and primarily induced P-selectin expression. Co-incubation of gal-1 and CXCL4 potentiated platelet aggregation compared with gal-1 alone. Whereas neither gal-1 and CXCL4 induced PS-exposure on platelets, prior removal of surface sialic acid strongly potentiated PS exposure. In addition, neuraminidase treatment increased the binding of gal-1 to platelets and lowered the activation threshold for gal-1. However, CXCL4 did not affect binding of gal-1 to platelets. Taken together, stimulation of platelets with gal-1 and CXCL4 led to distinct and complementary activation profiles, with additive rather than synergistic effects.
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Affiliation(s)
- Annemiek Dickhout
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Bibian M. E. Tullemans
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Johan W. M. Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Victor L. J. L. Thijssen
- Amsterdam UMC, location VUmc, Medical Oncology & Radiation Oncology, Amsterdam, The Netherlands
- * E-mail: (RRK); (VLJLT)
| | - Marijke J. E. Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Rory R. Koenen
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
- Institute for Cardiovascular Prevention (IPEK), LMU Munich, Munich, Germany
- * E-mail: (RRK); (VLJLT)
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Hou Y, Shao L, Zhou H, Liu Y, Fisk DG, Spiteri E, Zehnder JL, Peng J, Zhang BM, Hou M. Identification of a pathogenic TUBB1 variant in a Chinese family with congenital macrothrombocytopenia through whole genome sequencing. Platelets 2021; 32:1108-1112. [PMID: 33400601 DOI: 10.1080/09537104.2020.1869714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Congenital macrothrombocytopenia is a genetically heterogeneous group of rare disorders. We herein report a large Chinese family presented with phenotypic variability involving thrombocytopenia and/or giant platelets. Whole genome sequencing (WGS) of the proband and one of his affected brothers identified a potentially pathogenic c.952 C > T heterozygous variant in the TUBB1 gene. This p.R318W β1-tubulin variant was also identified in three additional siblings and five members of the next generation. These findings were consistent with an autosomal dominant inheritance with incomplete penetrance. Moreover, impaired platelet agglutination in response to ristocetin was detected in the patient's brother. Half of the family members harboring the p.R318W mutation displayed significantly decreased external release of p-selectin by stimulated platelets. The p.R318W β1-tubulin mutation was identified for the first time in a Chinese family with congenital macrothrombocytopenia using WGS as an unbiased sequencing approach. Affected individuals within the family demonstrated impaired platelet aggregation and/or release functions.
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Affiliation(s)
- Yu Hou
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Linlin Shao
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Hai Zhou
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yanfeng Liu
- Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Dianna G Fisk
- Clinical Genomics Program, Stanford Health Care, Palo Alto, United States
| | - Elizabeth Spiteri
- Clinical Genomics Program, Stanford Health Care, Palo Alto, United States.,Department of Pathology, Stanford University School of Medicine, Palo Alto, United States
| | - James L Zehnder
- Department of Pathology, Stanford University School of Medicine, Palo Alto, United States
| | - Jun Peng
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Bing M Zhang
- Department of Pathology, Stanford University School of Medicine, Palo Alto, United States
| | - Ming Hou
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Leading Research Group of Scientific Innovation, Department of Science and Technology of Shandong Province, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
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9
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Jiang Q, Mao R, Wu J, Chang L, Zhu H, Zhang G, Ding Z, Zhang J. Platelet activation during chronic hepatitis B infection exacerbates liver inflammation and promotes fibrosis. J Med Virol 2020; 92:3319-3326. [PMID: 31769518 DOI: 10.1002/jmv.25641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 11/19/2019] [Indexed: 01/16/2023]
Abstract
Recurrent hepatitis activity during chronic hepatitis B virus infection results in fibrosis and even hepatocellular carcinoma. It is still unclear what causes acute exacerbation. As platelets have recently been identified as a significant role in inflammation, we here investigated the role of platelets in mediating liver damage in patients with chronic hepatitis B virus infection. Platelet aggregation testing and flow cytometry were carried out to evaluate platelet activation status in 121 patients chronically infected with hepatitis B across different phases of the condition. The correlation between platelet aggregation rate and liver inflammation or liver fibrosis index was evaluated. To investigate the genesis of platelet activation, several serum cytokines were also assessed by MILLIPLEX microsphere-based multiplex cytokine assay. Active hepatitis patients showed a higher aggregation rate than others. Levels of CD62p, a marker of platelet activation, were also increased in this group of patients. Positive correlations between platelet aggregation rate and liver inflammation or liver fibrosis were also noted, indicating a significant role of platelet in the progression of liver disease. The level of tumor necrosis factor-alpha, which is known to trigger platelet activation, was markedly higher in the active hepatitis group (P < .005). Based on the findings in our study, platelet activation plays a vital role in the progression of chronic hepatitis B virus infection. Antiplatelet therapy may provide a new means of hepatitis B infection treatment.
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Affiliation(s)
- Qirong Jiang
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Richeng Mao
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Jingwen Wu
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Lin Chang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Haoxiang Zhu
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Ge Zhang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Zhongren Ding
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jiming Zhang
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
- Department of Infectious Diseases, Jing'An District Centre Hospital of Shanghai, Fudan University, Shanghai, China
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10
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Babur Ö, Melrose AR, Cunliffe JM, Klimek J, Pang J, Sepp ALI, Zilberman-Rudenko J, Tassi Yunga S, Zheng T, Parra-Izquierdo I, Minnier J, McCarty OJT, Demir E, Reddy AP, Wilmarth PA, David LL, Aslan JE. Phosphoproteomic quantitation and causal analysis reveal pathways in GPVI/ITAM-mediated platelet activation programs. Blood 2020; 136:2346-2358. [PMID: 32640021 PMCID: PMC7702475 DOI: 10.1182/blood.2020005496] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 06/05/2020] [Indexed: 02/07/2023] Open
Abstract
Platelets engage cues of pending vascular injury through coordinated adhesion, secretion, and aggregation responses. These rapid, progressive changes in platelet form and function are orchestrated downstream of specific receptors on the platelet surface and through intracellular signaling mechanisms that remain systematically undefined. This study brings together cell physiological and phosphoproteomics methods to profile signaling mechanisms downstream of the immunotyrosine activation motif (ITAM) platelet collagen receptor GPVI. Peptide tandem mass tag (TMT) labeling, sample multiplexing, synchronous precursor selection (SPS), and triple stage tandem mass spectrometry (MS3) detected >3000 significant (false discovery rate < 0.05) phosphorylation events on >1300 proteins over conditions initiating and progressing GPVI-mediated platelet activation. With literature-guided causal inference tools, >300 site-specific signaling relations were mapped from phosphoproteomics data among key and emerging GPVI effectors (ie, FcRγ, Syk, PLCγ2, PKCδ, DAPP1). Through signaling validation studies and functional screening, other less-characterized targets were also considered within the context of GPVI/ITAM pathways, including Ras/MAPK axis proteins (ie, KSR1, SOS1, STAT1, Hsp27). Highly regulated GPVI/ITAM targets out of context of curated knowledge were also illuminated, including a system of >40 Rab GTPases and associated regulatory proteins, where GPVI-mediated Rab7 S72 phosphorylation and endolysosomal maturation were blocked by TAK1 inhibition. In addition to serving as a model for generating and testing hypotheses from omics datasets, this study puts forth a means to identify hemostatic effectors, biomarkers, and therapeutic targets relevant to thrombosis, vascular inflammation, and other platelet-associated disease states.
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Affiliation(s)
- Özgün Babur
- Department of Molecular and Medical Genetics
- Computational Biology Program
| | | | | | | | | | | | | | | | | | | | | | | | - Emek Demir
- Department of Molecular and Medical Genetics
- Computational Biology Program
| | | | | | - Larry L David
- Proteomics Shared Resource
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR
| | - Joseph E Aslan
- Knight Cardiovascular Institute
- Department of Biomedical Engineering
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR
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11
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Alarabi AB, Karim ZA, Ramirez JEM, Hernandez KR, Lozano PA, Rivera JO, Alshbool FZ, Khasawneh FT. Short-Term Exposure to Waterpipe/Hookah Smoke Triggers a Hyperactive Platelet Activation State and Increases the Risk of Thrombogenesis. Arterioscler Thromb Vasc Biol 2020; 40:335-349. [PMID: 31941383 DOI: 10.1161/atvbaha.119.313435] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Cardiovascular disease is a major public health problem. Among cardiovascular disease's risk factors, tobacco smoking is considered the single most preventable cause of death, with thrombosis being the main mechanism of cardiovascular disease mortality in smokers. While tobacco smoking has been on the decline, the use of waterpipes/hookah has been rising, mainly due to the perception that they are less harmful than regular cigarettes. Strikingly, there are few studies on the negative effects of waterpipes on the cardiovascular system, and none regarding their direct contribution to thrombus formation. Approach and Results: We used a waterpipe whole-body exposure protocol that mimics real-life human exposure scenarios and investigated its effects, relative to clean air, on platelet function, hemostasis, and thrombogenesis. We found that waterpipe smoke (WPS)-exposed mice exhibited both shortened thrombus occlusion and bleeding times. Further, our results show that platelets from WPS-exposed mice are hyperactive, with enhanced agonist-induced aggregation, dense and α-granule secretion, αIIbβ3 integrin activation, phosphatidylserine expression, and platelet spreading, when compared with clean air-exposed platelets. Finally, at the molecular level, it was found that Akt (protein kinase B) and ERK (extracellular signal-regulated kinases) phosphorylation are enhanced in the WPS and in nicotine-treated platelets. CONCLUSIONS Our findings demonstrate that WPS exposure directly modulates hemostasis and increases the risk of thrombosis and that this is mediated, in part, via a state of platelet hyperactivity. The negative health impact of WPS/hookah, therefore, should not be underestimated. Moreover, this study should also help in raising public awareness of the toxic effects of waterpipe/hookah.
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Affiliation(s)
- Ahmed B Alarabi
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Zubair A Karim
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Jean E Montes Ramirez
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Keziah R Hernandez
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Patricia A Lozano
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - José O Rivera
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Fatima Z Alshbool
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
| | - Fadi T Khasawneh
- From the Pharmaceutical Sciences, School of Pharmacy, The University of Texas at El Paso
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12
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Vögtle T, Sharma S, Mori J, Nagy Z, Semeniak D, Scandola C, Geer MJ, Smith CW, Lane J, Pollack S, Lassila R, Jouppila A, Barr AJ, Ogg DJ, Howard TD, McMiken HJ, Warwicker J, Geh C, Rowlinson R, Abbott WM, Eckly A, Schulze H, Wright GJ, Mazharian A, Fütterer K, Rajesh S, Douglas MR, Senis YA. Heparan sulfates are critical regulators of the inhibitory megakaryocyte-platelet receptor G6b-B. eLife 2019; 8:e46840. [PMID: 31436532 PMCID: PMC6742478 DOI: 10.7554/elife.46840] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 08/21/2019] [Indexed: 02/06/2023] Open
Abstract
The immunoreceptor tyrosine-based inhibition motif (ITIM)-containing receptor G6b-B is critical for platelet production and activation. Loss of G6b-B results in severe macrothrombocytopenia, myelofibrosis and aberrant platelet function in mice and humans. Using a combination of immunohistochemistry, affinity chromatography and proteomics, we identified the extracellular matrix heparan sulfate (HS) proteoglycan perlecan as a G6b-B binding partner. Subsequent in vitro biochemical studies and a cell-based genetic screen demonstrated that the interaction is specifically mediated by the HS chains of perlecan. Biophysical analysis revealed that heparin forms a high-affinity complex with G6b-B and mediates dimerization. Using platelets from humans and genetically modified mice, we demonstrate that binding of G6b-B to HS and multivalent heparin inhibits platelet and megakaryocyte function by inducing downstream signaling via the tyrosine phosphatases Shp1 and Shp2. Our findings provide novel insights into how G6b-B is regulated and contribute to our understanding of the interaction of megakaryocytes and platelets with glycans.
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Affiliation(s)
- Timo Vögtle
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Sumana Sharma
- Cell Surface Signalling LaboratoryWellcome Trust Sanger InstituteCambridgeUnited Kingdom
| | - Jun Mori
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Zoltan Nagy
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Daniela Semeniak
- Institute of Experimental BiomedicineUniversity Hospital WürzburgWürzburgGermany
| | - Cyril Scandola
- Université de Strasbourg, Institut National de la Santé et de la Recherche Médicale, Etablissement Français du Sang Grand Est, Unité Mixte de Recherche-S 1255, Fédération de Médecine Translationnelle de StrasbourgStrasbourgFrance
| | - Mitchell J Geer
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Christopher W Smith
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Jordan Lane
- Sygnature Discovery LimitedNottinghamUnited Kingdom
| | | | - Riitta Lassila
- Coagulation Disorders Unit, Department of Hematology, Comprehensive Cancer CenterUniversity of Helsinki, Helsinki University HospitalHelsinkiFinland
- Aplagon OyHelsinkiFinland
| | - Annukka Jouppila
- Coagulation Disorders UnitHelsinki University Hospital Research InstituteHelsinkiFinland
| | - Alastair J Barr
- Department of Biomedical Science, Faculty of Science & TechnologyUniversity of WestminsterLondonUnited Kingdom
| | - Derek J Ogg
- Peak Proteins LimitedAlderley ParkCheshireUnited Kingdom
| | - Tina D Howard
- Peak Proteins LimitedAlderley ParkCheshireUnited Kingdom
| | | | - Juli Warwicker
- Peak Proteins LimitedAlderley ParkCheshireUnited Kingdom
| | - Catherine Geh
- Peak Proteins LimitedAlderley ParkCheshireUnited Kingdom
| | | | - W Mark Abbott
- Peak Proteins LimitedAlderley ParkCheshireUnited Kingdom
| | - Anita Eckly
- Université de Strasbourg, Institut National de la Santé et de la Recherche Médicale, Etablissement Français du Sang Grand Est, Unité Mixte de Recherche-S 1255, Fédération de Médecine Translationnelle de StrasbourgStrasbourgFrance
| | - Harald Schulze
- Institute of Experimental BiomedicineUniversity Hospital WürzburgWürzburgGermany
| | - Gavin J Wright
- Cell Surface Signalling LaboratoryWellcome Trust Sanger InstituteCambridgeUnited Kingdom
| | - Alexandra Mazharian
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Klaus Fütterer
- School of Biosciences, College of Life and Environmental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Sundaresan Rajesh
- Institute of Cancer and Genomic Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Michael R Douglas
- Institute of Inflammation and Ageing, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
- Department of NeurologyDudley Group NHS Foundation TrustDudleyUnited Kingdom
- School of Life and Health SciencesAston UniversityBirminghamUnited Kingdom
| | - Yotis A Senis
- Institute of Cardiovascular Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
- Université de Strasbourg, Institut National de la Santé et de la Recherche Médicale, Etablissement Français du Sang Grand Est, Unité Mixte de Recherche-S 1255, Fédération de Médecine Translationnelle de StrasbourgStrasbourgFrance
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13
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Gkalea V, Tang S, Favier R, Kuadjovi C, Bégon E, Bugaut H, Bordet JC, Bachmeyer C, Blum L. Progressive pigmented purpuric dermatosis and platelet delta storage pool deficiency in a child. Pediatr Blood Cancer 2019; 66:e27748. [PMID: 30977588 DOI: 10.1002/pbc.27748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/07/2019] [Accepted: 03/13/2019] [Indexed: 01/15/2023]
Affiliation(s)
- Vasiliki Gkalea
- Laboratoire d'Hématologie, Hôpital Tenon (AP-HP), Paris, France
| | - Solange Tang
- Service de Dermatologie, Hôpital René Dubos, Pontoise, France
| | - Remi Favier
- Centre de Référence des Pathologies Plaquettaires, Hôpital Armand Trousseau (AP-HP), Paris, France
| | | | - Edouard Bégon
- Service de Dermatologie, Hôpital René Dubos, Pontoise, France
| | - Hélène Bugaut
- Service de Dermatologie, Hôpital René Dubos, Pontoise, France
| | | | - Claude Bachmeyer
- Service de Médecine Interne, Hôpital Tenon (AP-HP), Paris, France
| | - Laurent Blum
- Service de Dermatologie, Hôpital René Dubos, Pontoise, France
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14
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Khan AO, Maclachlan A, Lowe GC, Nicolson PLR, Ghaithi RA, Thomas SG, Watson SP, Pike JA, Morgan NV. High-throughput platelet spreading analysis: a tool for the diagnosis of platelet-based bleeding disorders. Haematologica 2019; 105:e124-e128. [PMID: 31221775 DOI: 10.3324/haematol.2019.225912] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Abdullah O Khan
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
| | - Annabel Maclachlan
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
| | - Gillian C Lowe
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
| | - Phillip L R Nicolson
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
| | - Rashid Al Ghaithi
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
| | - Steven G Thomas
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham.,Centre of Membrane and Protein and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Steve P Watson
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham.,Centre of Membrane and Protein and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Jeremy A Pike
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham.,Centre of Membrane and Protein and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Neil V Morgan
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham
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15
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Qasim H, Karim ZA, Hernandez KR, Lozano D, Khasawneh FT, Alshbool FZ. Arhgef1 Plays a Vital Role in Platelet Function and Thrombogenesis. J Am Heart Assoc 2019; 8:e011712. [PMID: 30994039 PMCID: PMC6512111 DOI: 10.1161/jaha.118.011712] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/25/2019] [Indexed: 01/09/2023]
Abstract
Background Platelets are the cellular mediators of hemostasis and thrombosis, and their function is regulated by a number of molecular mediators, such as small GTP ases. These small GTP ases are themselves regulated by guanine nucleotide exchange factors such as Arhgefs, several of which are found in platelets, including the highly expressed Arhgef1. However, the role of Arhgef1 in platelets has not yet been investigated. Methods and Results We employed mice with genetic deletion of Arhgef1 (ie, Arhgef1-/-) and investigated their platelet phenotype by employing a host of in vivo and in vitro platelet assays. Our results indicate that Arhgef1-/- mice had prolonged carotid artery occlusion and tail bleeding times. Moreover, platelets from these mice exhibited defective aggregation, dense and α granule secretion, α II bβ3 integrin activation, clot retraction and spreading, in comparison to their wild-type littermates. Finally, we also found that the mechanism by which Arhgef1 regulates platelets is mediated in part by a defect in the activation of the RhoA-Rho-associated kinase axis, but not Rap1b. Conclusions Our data demonstrate, for the first time, that Arhgef1 plays a critical role in platelet function, in vitro and in vivo.
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Affiliation(s)
- Hanan Qasim
- Department of Pharmaceutical SciencesSchool of PharmacyThe University of Texas El PasoEl PasoTX
| | - Zubair A. Karim
- Department of Pharmaceutical SciencesSchool of PharmacyThe University of Texas El PasoEl PasoTX
| | - Keziah R. Hernandez
- Department of Pharmaceutical SciencesSchool of PharmacyThe University of Texas El PasoEl PasoTX
| | | | - Fadi T. Khasawneh
- Department of Pharmaceutical SciencesSchool of PharmacyThe University of Texas El PasoEl PasoTX
| | - Fatima Z. Alshbool
- Department of Pharmaceutical SciencesSchool of PharmacyThe University of Texas El PasoEl PasoTX
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16
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Individual variations in platelet reactivity towards ADP, epinephrine, collagen and nitric oxide, and the association to arterial function in young, healthy adults. Thromb Res 2018; 174:5-12. [PMID: 30543988 DOI: 10.1016/j.thromres.2018.12.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/13/2018] [Accepted: 12/05/2018] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Platelet aggregation and secretion can be induced by a large number of endogenous activators, such as collagen, adenosine diphosphate (ADP) and epinephrine. Conversely, the blood vessel endothelium constitutively release platelet inhibitors including nitric oxide (NO) and prostacyclin. NO and prostacyclin are also well-known vasodilators and contribute to alterations in local blood flow and systemic blood pressure. MATERIALS AND METHODS In this study we investigated individual variations in platelet reactivity and arterial functions including blood pressure and flow-mediated vasodilation (FMD) in 43 young, healthy individuals participating in the Lifestyle, Biomarkers and Atherosclerosis (LBA) study. Platelet aggregation and dense granule secretion were measured simultaneously by light transmission and luminescence. FMD was measured with ultrasound. RESULTS The platelet function assay showed inter-individual differences in platelet reactivity. Specifically, a sub-group of individuals had platelets with an increased response to low concentrations of ADP and epinephrine, but not collagen. When the NO-donor S-nitroso-N-acetyl-DL-penicillamine (SNAP) was combined with high doses of these platelet activators, the results indicated for sub-groups of NO-sensitive and NO-insensitive platelets. The individuals with NO-sensitive platelets in response to SNAP in combination with collagen had a higher capacity of FMD of the arteria brachialis. CONCLUSIONS Platelet reactivity towards ADP, epinephrine and NO differs between young, healthy individuals. Some individuals have a more effective response towards NO, both in the aspect of platelet inhibition ex vivo, as well as vasodilation in vivo.
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17
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Lowe GC, Fickowska R, Al Ghaithi R, Maclachlan A, Harrison P, Lester W, Watson SP, Myers B, Clark J, Morgan NV. Investigation of the contribution of an underlying platelet defect in women with unexplained heavy menstrual bleeding. Platelets 2018; 30:56-65. [PMID: 30520671 PMCID: PMC6406209 DOI: 10.1080/09537104.2018.1543865] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Heavy menstrual bleeding (HMB) is often undiagnosed in women and can cause discomfort and distress. A haemostatic cause for excessive bleeding is often not routinely investigated and can lead to hysterectomy at an early age. A prospective cohort study was carried out to determine whether certain patients with unexplained HMB have an underlying platelet function defect (PFD). The Genotyping and Phenotyping of Platelets (GAPP) study recruited 175 women with HMB and 44 unrelated volunteers from 25 Haemophilia Centres across the UK, and a tertiary gynaecology service. Bleeding history was assessed using the International Society on Thrombosis and Haemostasis Bleeding Assessment Tool (ISTH-BAT). Platelet count, platelet size, haemoglobin and mean corpuscular volume were measured in whole blood using the Sysmex XN-1000 Haematology Analyzer. Platelet function testing using lumiaggregometry and flow cytometry was performed in patients included in this study. A PFD was identified in 47% (82/175) of patients with HMB. Cutaneous bleeding was the most frequent additional bleeding symptom (89% in PFD and 83% with no PFD). Whole blood platelet count was significantly lower (P < 0.0001) between the PFD group and no PFD group. The prevalence of anaemia did not differ between patients and healthy volunteers. Clinical evaluation alone is insufficient to determine presence of an underlying PFD in patients with HMB. Platelet function tests may be considered and clinical guidelines may include them in their algorithms. An appropriate diagnosis and subsequent tailored management of HMB may prevent unnecessary surgery and help manage future haemostatic challenges.
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Affiliation(s)
- Gillian C Lowe
- a Comprehensive Care Haemophilia Centre , University Hospital Birmingham NHS Foundation Trust , Birmingham , UK
| | - Roksana Fickowska
- b Institute of Cardiovascular Sciences, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
| | - Rashid Al Ghaithi
- c Institute of Inflammation and Ageing, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
| | - Annabel Maclachlan
- b Institute of Cardiovascular Sciences, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
| | - Paul Harrison
- c Institute of Inflammation and Ageing, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
| | - Will Lester
- a Comprehensive Care Haemophilia Centre , University Hospital Birmingham NHS Foundation Trust , Birmingham , UK
| | - Steve P Watson
- b Institute of Cardiovascular Sciences, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
| | - Bethan Myers
- d Department of Haematology , Lincoln County Hospital , Lincoln , UK.,e Haemostasis & Thrombosis Unit, Leicester Royal Infirmary , University Hospitals Of Leicester NHS Trust , Leicester , UK
| | - Justin Clark
- f Department of Gynaecology , Birmingham Women's and Children's NHS Foundation Trust , Birmingham , UK
| | - Neil V Morgan
- b Institute of Cardiovascular Sciences, College of Medical and Dental Sciences , University of Birmingham , Birmingham , UK
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18
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Al Ghaithi R, Mori J, Nagy Z, Maclachlan A, Hardy L, Philippou H, Hethershaw E, Morgan NV, Senis YA, Harrison P. Evaluation of the Total Thrombus-Formation System (T-TAS): application to human and mouse blood analysis. Platelets 2018; 30:893-900. [PMID: 30365350 DOI: 10.1080/09537104.2018.1535704] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 12/26/2022]
Abstract
The Total Thrombus-formation Analyser System (T-TAS) is a whole blood flow chamber system for the measurement of in vitro thrombus formation under variable shear stress conditions. Our current study sought to evaluate the potential utility of the T-TAS for the measurement of thrombus formation within human and mouse whole blood. T-TAS microchips (collagen, PL chip; collagen/tissue thromboplastin, AR chip) were used to analyze platelet (PL) or fibrin-rich thrombus formation, respectively. Blood samples from humans (healthy and patients with mild bleeding disorders) and wild-type (WT), mice were tested. Light transmission lumi-aggregometer (lumi-LTA) was performed in PRP using several concentrations of ADP, adrenaline, arachidonic acid, collagen, PAR-1 peptide and ristocetin. Thrombus growth (N = 22) increased with shear within PL (4:40 ± 1.11, 3:25 ± 0.43 and 3:12 ± 0.48 mins [1000, 1500 and 2000s-1]) and AR chips (3:55 ± 0.42 and 1:49 ± 0.19 [240s-1 and 600s-1]). The area under the curve (AUC) on the PL chip was also reduced at 1000s-1 compared to 1500/2000s-1 (260 ± 51.7, 317 ± 55.4 and 301 ± 66.2, respectively). In contrast, no differences in the AUC between 240s-1 and 600s-1 were observed in the AR chip (1593 ± 122 and 1591 ± 158). The intra-assay coefficient of variation (CV) (n = 10) in the PL chip (1000s-1) and AR chip (240s-1) were T1014.1%, T6016.7%, T10-6022.8% and AUC1024.4% or T10 9.03%, T808.64%, T10-8023.8% and AUC305.1%. AR chip thrombus formation was inhibited by rivaroxaban (1 µM), but not with ticagrelor (10 µM). In contrast, PL chip thrombus formation was totally inhibited by ticagrelor. T-TAS shows an overall agreement with lumi-LTA in 87% of patients (n = 30) with normal PL counts recruited into the genotyping and phenotyping of platelet (GAPP) study and suspected to have a PL function defect. The onset (T10) of thrombus formation in WT mice (N = 4) was shorter when compared to humans e.g. PL chip (1000s-1) T10 were 02:02 ± 00:23 and 03:30 ± 0:45, respectively). T-TAS measures in vitro thrombus formation and can be used for monitoring antithrombotic therapy, investigating patients with suspected PL function defects and monitoring PL function within mice.
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Affiliation(s)
- Rashid Al Ghaithi
- Institute of Inflammation and Ageing, University of Birmingham , Birmingham , UK
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
- Haematology and Blood Transfusion Department, The Royal Hospital, Ministry of Health , Muscat , Sultanate of Oman
| | - Jun Mori
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
| | - Zoltan Nagy
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
| | - Annabel Maclachlan
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
| | - Lewis Hardy
- Leeds Institute of Cardiovascular and Metabolic Medicine LIGHT Laboratories, University of Leeds , Leeds , West Yorkshire , UK
| | - Helen Philippou
- Leeds Institute of Cardiovascular and Metabolic Medicine LIGHT Laboratories, University of Leeds , Leeds , West Yorkshire , UK
| | - Emma Hethershaw
- Leeds Institute of Cardiovascular and Metabolic Medicine LIGHT Laboratories, University of Leeds , Leeds , West Yorkshire , UK
| | - Neil V Morgan
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
| | - Yotis A Senis
- Institute of Cardiovascular Sciences, Institute for Biomedical Research, University of Birmingham , Birmingham , UK
| | - Paul Harrison
- Institute of Inflammation and Ageing, University of Birmingham , Birmingham , UK
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19
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Johnson B, Doak R, Allsup D, Astwood E, Evans G, Grimley C, James B, Myers B, Stokley S, Thachil J, Wilde J, Williams M, Makris M, Lowe GC, Wallis Y, Daly ME, Morgan NV. A comprehensive targeted next-generation sequencing panel for genetic diagnosis of patients with suspected inherited thrombocytopenia. Res Pract Thromb Haemost 2018; 2:640-652. [PMID: 30349881 PMCID: PMC6178765 DOI: 10.1002/rth2.12151] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/20/2018] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Inherited thrombocytopenias (ITs) are a heterogeneous group of disorders characterized by low platelet counts and often disproportionate bleeding with over 30 genes currently implicated. Previously the UK-GAPP study using whole exome sequencing (WES) identified a pathogenic variant in 19 of 47 (40%) patients of which 71% had variants in genes known to cause IT. AIMS To employ a targeted next-generation sequencing platform to improve efficiency of diagnostic testing and reduce overall costs. METHODS We have developed an IT-specific gene panel as a pre-screen for patients prior to WES using the Agilent SureSelectQXT transposon-based enrichment system. RESULTS Thirty-one patients were analyzed using the panel-based sequencing, of which; 10% (3/31) were identified with a classified pathogenic variant, 16% (5/31) were identified with a likely pathogenic variant, 51% (16/31) were identified with variants of unknown significance, and 23% (7/31) were identified with either no variant or a benign variant. DISCUSSION AND CONCLUSION Although requiring further clarification of the impact of the genetic variations, the application of an IT-specific next generation sequencing panel is an viable method of pre-screening patients for variants in known IT-causing genes prior to WES. With an added benefit of distinguishing IT from idiopathic thrombocytopenic purpura (ITP) and the potential to identify variants in genes known to have a predisposition to hematological malignancies, it could become a critical step in improving patient clinical management.
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Affiliation(s)
- Ben Johnson
- Institute of Cardiovascular SciencesCollege of Medical and Dental SciencesUniversity of BirminghamBirminghamUK
| | - Rachel Doak
- West Midlands Regional Genetics LaboratoryBirmingham Women's HospitalBirminghamUK
| | - David Allsup
- Hull York Medical SchoolUniversity of HullHullUK
| | - Emma Astwood
- Nottingham Haemophilia CentreNottingham University HospitalNottinghamUK
| | - Gillian Evans
- Kent Haemophilia CentreKent & Canterbury HospitalCanterburyUK
| | - Charlotte Grimley
- Nottingham Haemophilia CentreNottingham University HospitalNottinghamUK
| | - Beki James
- Regional Centre for Paediatric HaematologyLeeds Children's HospitalLeedsUK
| | - Bethan Myers
- Department of HaematologyLincoln County HospitalLincolnUK
| | - Simone Stokley
- Nottingham Haemophilia CentreNottingham University HospitalNottinghamUK
| | - Jecko Thachil
- Department of HaematologyManchester Royal InfirmaryManchesterUK
| | - Jonathan Wilde
- Comprehensive Care Haemophilia CentreUniversity Hospitals NHS Foundation TrustBirminghamUK
| | - Mike Williams
- Department of HaematologyBirmingham Children's HospitalBirminghamUK
| | - Mike Makris
- Department of Infection, Immunity and Cardiovascular ScienceUniversity of Sheffield Medical SchoolUniversity of SheffieldSheffieldUK
| | - Gillian C. Lowe
- Comprehensive Care Haemophilia CentreUniversity Hospitals NHS Foundation TrustBirminghamUK
| | - Yvonne Wallis
- West Midlands Regional Genetics LaboratoryBirmingham Women's HospitalBirminghamUK
| | - Martina E. Daly
- Department of Infection, Immunity and Cardiovascular ScienceUniversity of Sheffield Medical SchoolUniversity of SheffieldSheffieldUK
| | - Neil V. Morgan
- Institute of Cardiovascular SciencesCollege of Medical and Dental SciencesUniversity of BirminghamBirminghamUK
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20
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Qasim H, Karim ZA, Silva-Espinoza JC, Khasawneh FT, Rivera JO, Ellis CC, Bauer SL, Almeida IC, Alshbool FZ. Short-Term E-Cigarette Exposure Increases the Risk of Thrombogenesis and Enhances Platelet Function in Mice. J Am Heart Assoc 2018; 7:JAHA.118.009264. [PMID: 30021806 PMCID: PMC6201451 DOI: 10.1161/jaha.118.009264] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Cardiovascular disease is the main cause of death in the United States, with smoking being the primary preventable cause of premature death, and thrombosis being the main mechanism of cardiovascular mortality in smokers. Due to the perception that electronic/e‐cigarettes are “safer/less harmful” than conventional cigarettes, their usage—among a variety of ages—has increased tremendously during the past decade. Notably, there are limited studies regarding the negative effects of e‐cigarettes on the cardiovascular system, which is also the subject of significant debate. Methods and Results We employed a passive e‐VapeTM vapor inhalation system and developed an in vivo whole‐body e‐cigarette mouse exposure protocol that mimics real‐life human exposure scenarios/conditions and investigated the effects of e‐cigarettes and clean air on platelet function and thrombogenesis. Our results show that platelets from e‐cigarette–exposed mice are hyperactive, with enhanced aggregation, dense and α granule secretion, activation of the αIIbβ3 integrin, phosphatidylserine expression, and Akt and ERK activation, when compared with clean air–exposed platelets. E‐cigarette–exposed platelets were also found to be resistant to inhibition by prostacyclin, relative to clean air. Furthermore, the e‐cigarette–exposed mice exhibited a shortened thrombosis occlusion and bleeding times. Conclusions Taken together, our data demonstrate for the first time that e‐cigarettes alter physiological hemostasis and increase the risk of thrombogenic events. This is attributable, at least in part, to the hyperactive state of platelets. Thus, the negative health consequences of e‐cigarette exposure should not be underestimated and warrant further investigation.
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Affiliation(s)
- Hanan Qasim
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
| | - Zubair A Karim
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
| | - Juan C Silva-Espinoza
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
| | - Fadi T Khasawneh
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
| | - José O Rivera
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
| | - Cameron C Ellis
- Border Biomedical Research Center, Department of Biological Sciences, College of Science, University of Texas El Paso, TX
| | - Stephanie L Bauer
- Border Biomedical Research Center, Department of Biological Sciences, College of Science, University of Texas El Paso, TX
| | - Igor C Almeida
- Border Biomedical Research Center, Department of Biological Sciences, College of Science, University of Texas El Paso, TX
| | - Fatima Z Alshbool
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas El Paso, TX
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21
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Looße C, Swieringa F, Heemskerk JWM, Sickmann A, Lorenz C. Platelet proteomics: from discovery to diagnosis. Expert Rev Proteomics 2018; 15:467-476. [PMID: 29787335 DOI: 10.1080/14789450.2018.1480111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Platelets are the smallest cells within the circulating blood with key roles in physiological hemostasis and pathological thrombosis regulated by the onset of activating/inhibiting processes via receptor responses and signaling cascades. Areas covered: Proteomics as well as genomic approaches have been fundamental in identifying and quantifying potential targets for future diagnostic strategies in the prevention of bleeding and thrombosis, and uncovering the complexity of platelet functions in health and disease. In this article, we provide a critical overview on current functional tests used in diagnostics and the future perspectives for platelet proteomics in clinical applications. Expert commentary: Proteomics represents a valuable tool for the identification of patients with diverse platelet associated defects. In-depth validation of identified biomarkers, e.g. receptors, signaling proteins, post-translational modifications, in large cohorts is decisive for translation into routine clinical diagnostics.
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Affiliation(s)
- Christina Looße
- a Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund , Germany
| | - Frauke Swieringa
- a Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund , Germany
| | - Johan W M Heemskerk
- b Department of Biochemistry , CARIM, Maastricht University , Maastricht , The Netherlands
| | - Albert Sickmann
- a Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund , Germany.,c Medizinisches Proteom-Center , Medizinische Fakultät, Ruhr-Universität Bochum , Bochum , Germany.,d Department of Chemistry, College of Physical Sciences , University of Aberdeen , Aberdeen , UK
| | - Christin Lorenz
- a Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund , Germany
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22
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Zia F, Kendall M, Watson SP, Mendes PM. Platelet aggregation induced by polystyrene and platinum nanoparticles is dependent on surface area. RSC Adv 2018; 8:37789-37794. [PMID: 30713685 PMCID: PMC6333253 DOI: 10.1039/c8ra07315e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 10/23/2018] [Indexed: 01/07/2023] Open
Abstract
Nanoparticles are key components underlying recent technological advances in various industrial and medical fields, and thus understanding their mode of interaction with biological systems is essential. However, while several nanoparticle systems have been shown to interact with blood platelets, many questions remain concerning the mechanisms of platelet activation and the role that the physicochemical properties of nanoparticles play in inducing platelet aggregation. Here, using negatively charged polystyrene nanoparticles with sizes of 25, 50, 119, 151, 201 nm and negatively charged platinum nanoparticles with sizes of 7 and 73 nm, we show that it is not the size of the nanoparticles but rather the nanoparticle surface area that is critical in mediating the effects on platelet activation. The nanoparticles stimulate platelet aggregation through passive (agglutination) and activation of integrin αIIbβ3 through a pathway regulated by Src and Syk tyrosine kinase. Nanoparticles are key components underlying recent technological advances in various industrial and medical fields, and thus understanding their mode of interaction with biological systems is essential.![]()
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Affiliation(s)
- Fatima Zia
- School of Chemical Engineering, College of Engineering and Physical Sciences, University of Birmingham B15 2TT, UK. .,Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, The Midlands, UK
| | - Michaela Kendall
- Adelan/School of Engineering, Aston University, Birmingham B4 7ET, UK. http://www.adelan.co.uk
| | - Steve P Watson
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, The Midlands, UK.,Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham B15 2TT, UK.
| | - Paula M Mendes
- School of Chemical Engineering, College of Engineering and Physical Sciences, University of Birmingham B15 2TT, UK. .,Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, The Midlands, UK
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23
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Al Ghaithi R, Drake S, Watson SP, Morgan NV, Harrison P. Comparison of multiple electrode aggregometry with lumi-aggregometry for the diagnosis of patients with mild bleeding disorders. J Thromb Haemost 2017; 15:2045-2052. [PMID: 28762630 DOI: 10.1111/jth.13784] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Indexed: 08/31/2023]
Abstract
Essentials There is a clinical need for new technologies to measure platelet function in whole blood. Mild bleeding disorders were evaluated using multiple electrode aggregometry (MEA). MEA is insensitive at detecting patients with mild platelet function and secretion defects. More studies are required to investigate MEA in patients with a defined set of platelet disorders. SUMMARY Background Multiple electrode aggregometry (MEA) measures changes in electrical impedance caused by platelet aggregation in whole blood. This approach is faster, more convenient and offers the advantage over light transmission aggregometry (LTA) of assessing platelet function in whole blood and reducing preanalytical errors associated with preparation of platelet-rich plasma (PRP). Several studies indicate the utility of this method in assessing platelet inhibition in individuals taking antiplatelet agents (e.g. aspirin and clopidogrel). Objective Our current study sought to evaluate the ability of MEA in diagnosing patients with mild bleeding disorders by comparison with light transmission lumi-aggregometry (lumi-LTA). Methods Forty healthy subjects and 109 patients with a clinical diagnosis of a mild bleeding disorder were recruited into the UK Genotyping and Phenotyping of Platelets study (GAPP, ISRCTN 77951167). MEA was performed on whole blood using one or two concentrations of ADP, PAR-1 peptide, arachidonic acid and collagen. Lumi-LTA was performed in PRP using several concentrations of ADP, adrenaline, arachidonic acid, collagen, PAR-1 peptide and ristocetin. Results Of 109 patients tested, 54 (49%) patients gave abnormal responses by lumi-LTA to one or more agonists. In contrast, only 16 (15%) patients were shown to have abnormal responses to one or more agonists by MEA. Conclusions In this study we showed that MEA is less sensitive in identifying patients with abnormal platelet function relative to lumi-LTA.
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Affiliation(s)
- R Al Ghaithi
- Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK
- Institute of Cardiovascular Sciences University of Birmingham, University of Birmingham, Edgbaston, Birmingham, UK
| | - S Drake
- Institute of Cardiovascular Sciences University of Birmingham, University of Birmingham, Edgbaston, Birmingham, UK
| | - S P Watson
- Institute of Cardiovascular Sciences University of Birmingham, University of Birmingham, Edgbaston, Birmingham, UK
| | - N V Morgan
- Institute of Cardiovascular Sciences University of Birmingham, University of Birmingham, Edgbaston, Birmingham, UK
| | - P Harrison
- Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK
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24
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Abstract
Fibrin has recently been shown to activate platelets through the immunoglobulin receptor glycoprotein VI (GPVI). In the present study, we show that spreading of human platelets on fibrin is abolished in patients deficient in GPVI, confirming that fibrin activates human platelets through the immunoglobulin receptor. Using a series of proteolytic fragments, we show that D-dimer, but not the E fragment of fibrin, binds to GPVI and that immobilized D-dimer induces platelet spreading through activation of Src and Syk tyrosine kinases. In contrast, when platelets are activated in suspension, soluble D-dimer inhibits platelet aggregation induced by fibrin and collagen, but not by a collagen-related peptide composed of a repeat GPO sequence or by thrombin. Using surface plasmon resonance, we demonstrate that fibrin binds selectively to monomeric GPVI with a KD of 302 nM, in contrast to collagen, which binds primarily to dimeric GPVI. These results establish GPVI as the major signaling receptor for fibrin in human platelets and provide evidence that fibrin binds to a distinct configuration of GPVI. This indicates that it may be possible to develop agents that selectively block the interaction of fibrin but not collagen with the immunoglobulin receptor. Such agents are required to establish whether selective targeting of either interaction has the potential to lead to development of an antithrombotic agent with a reduced effect on bleeding relative to current antiplatelet drugs.
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25
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Johnson B, Lowe GC, Futterer J, Lordkipanidzé M, MacDonald D, Simpson MA, Sanchez-Guiú I, Drake S, Bem D, Leo V, Fletcher SJ, Dawood B, Rivera J, Allsup D, Biss T, Bolton-Maggs PH, Collins P, Curry N, Grimley C, James B, Makris M, Motwani J, Pavord S, Talks K, Thachil J, Wilde J, Williams M, Harrison P, Gissen P, Mundell S, Mumford A, Daly ME, Watson SP, Morgan NV. Whole exome sequencing identifies genetic variants in inherited thrombocytopenia with secondary qualitative function defects. Haematologica 2016; 101:1170-1179. [PMID: 27479822 DOI: 10.3324/haematol.2016.146316] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/10/2016] [Indexed: 12/11/2022] Open
Abstract
Inherited thrombocytopenias are a heterogeneous group of disorders characterized by abnormally low platelet counts which can be associated with abnormal bleeding. Next-generation sequencing has previously been employed in these disorders for the confirmation of suspected genetic abnormalities, and more recently in the discovery of novel disease-causing genes. However its full potential has not yet been exploited. Over the past 6 years we have sequenced the exomes from 55 patients, including 37 index cases and 18 additional family members, all of whom were recruited to the UK Genotyping and Phenotyping of Platelets study. All patients had inherited or sustained thrombocytopenia of unknown etiology with platelet counts varying from 11×109/L to 186×109/L. Of the 51 patients phenotypically tested, 37 (73%), had an additional secondary qualitative platelet defect. Using whole exome sequencing analysis we have identified "pathogenic" or "likely pathogenic" variants in 46% (17/37) of our index patients with thrombocytopenia. In addition, we report variants of uncertain significance in 12 index cases, including novel candidate genetic variants in previously unreported genes in four index cases. These results demonstrate that whole exome sequencing is an efficient method for elucidating potential pathogenic genetic variants in inherited thrombocytopenia. Whole exome sequencing also has the added benefit of discovering potentially pathogenic genetic variants for further study in novel genes not previously implicated in inherited thrombocytopenia.
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Affiliation(s)
- Ben Johnson
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Gillian C Lowe
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Jane Futterer
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Marie Lordkipanidzé
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - David MacDonald
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Michael A Simpson
- Division of Genetics and Molecular Medicine, King's College, London, UK
| | - Isabel Sanchez-Guiú
- Centro Regional de Hemodonación, Universidad de Murcia, IMIB-Arrixaca, Murcia, Spain
| | - Sian Drake
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Danai Bem
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Vincenzo Leo
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, University of Sheffield, UK
| | - Sarah J Fletcher
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Ban Dawood
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - José Rivera
- Centro Regional de Hemodonación, Universidad de Murcia, IMIB-Arrixaca, Murcia, Spain
| | - David Allsup
- Hull Haemophilia Treatment Centre, Hull and East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Hull, UK
| | - Tina Biss
- Department of Haematology, Royal Victoria Infirmary, Newcastle Upon Tyne, UK
| | | | - Peter Collins
- Arthur Bloom Haemophilia Centre, School of Medicine, Cardiff University, UK
| | - Nicola Curry
- Oxford Haemophilia & Thrombosis Centre, Churchill Hospital, Oxford, UK
| | | | - Beki James
- Regional Centre for Paediatric Haematology, Leeds Children's Hospital, UK
| | - Mike Makris
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, University of Sheffield, UK
| | | | - Sue Pavord
- Department of Haematology, Oxford University Hospitals NHS Foundation Trust, UK
| | - Katherine Talks
- Department of Haematology, Royal Victoria Infirmary, Newcastle Upon Tyne, UK
| | - Jecko Thachil
- Department of Haematology, Manchester Royal Infirmary, Manchester, UK
| | - Jonathan Wilde
- Adult Haemophilia Centre, Queen Elizabeth Hospital, Birmingham, UK
| | - Mike Williams
- Department of Haematology, Birmingham Children's Hospital, UK
| | - Paul Harrison
- School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Paul Gissen
- Medical Research Council, Laboratory for Molecular Cell Biology, University College London, UK
| | - Stuart Mundell
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, UK
| | - Andrew Mumford
- School of Cellular and Molecular Medicine, University of Bristol, UK
| | - Martina E Daly
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, University of Sheffield, UK
| | - Steve P Watson
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Neil V Morgan
- Institute for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
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26
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Latger-Cannard V, Philippe C, Bouquet A, Baccini V, Alessi MC, Ankri A, Bauters A, Bayart S, Cornillet-Lefebvre P, Daliphard S, Mozziconacci MJ, Renneville A, Ballerini P, Leverger G, Sobol H, Jonveaux P, Preudhomme C, Nurden P, Lecompte T, Favier R. Haematological spectrum and genotype-phenotype correlations in nine unrelated families with RUNX1 mutations from the French network on inherited platelet disorders. Orphanet J Rare Dis 2016; 11:49. [PMID: 27112265 PMCID: PMC4845427 DOI: 10.1186/s13023-016-0432-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 04/18/2016] [Indexed: 11/20/2022] Open
Abstract
Background Less than 50 patients with FPD/AML (OMIM 601309) have been reported as of today and there may an underestimation. The purpose of this study was to describe the natural history, the haematological features and the genotype-phenotype correlations of this entity in order to, first, screen it better and earlier, before leukaemia occurrence and secondly to optimize appropriate monitoring and treatment, in particular when familial stem cell transplantation is considered. Methods We have investigated 41 carriers of RUNX1 alteration belonging to nine unrelated French families with FPD/AML and two syndromic patients, registered in the French network on rare platelet disorders from 2005 to 2015. Results Five missense, one non-sense, three frameshift mutations and two large deletions involving several genes including RUNX1 were evidenced. The history of familial leukaemia was suggestive of FPD/AML in seven pedigrees, whereas an autosomal dominant pattern of lifelong thrombocytopenia was the clinical presentation of two. Additional syndromic features characterized two large sporadic deletions. Bleeding tendency was mild and thrombocytopenia moderate (>50 x109/L), with normal platelet volume. A functional platelet defect consistent with a δ-granule release defect was found in ten patients regardless of the type of RUNX1 alteration. The incidence of haematological malignancies was higher when the mutated RUNX1 allele was likely to cause a dominant negative effect (19/34) in comparison with loss of function alleles (3/9). A normal platelet count does not rule out the diagnosis of FPD/AML, since the platelet count was found normal for three mutated subjects, a feature that has a direct impact in the search for a related donor in case of allogeneic haematopoietic stem cell transplantation. Conclusions Platelet dysfunction suggestive of defective δ-granule release could be of values for the diagnosis of FPD/AML particularly when the clinical presentation is an autosomal dominant thrombocytopenia with normal platelet size in the absence of familial malignancies. The genotype-phenotype correlations might be helpful in genetic counselling and appropriate optimal therapeutic management.
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Affiliation(s)
- Veronique Latger-Cannard
- Service d'Hématologie Biologique, Centre Hospitalier Universitaire de Nancy, Nancy, France.,Centre de Compétence Nord-Est des Pathologies Plaquettaires (CCPP), Nancy, France
| | - Christophe Philippe
- Laboratoire de Génétique, Centre Hospitalier Universitaire de Nancy, Nancy, France
| | - Alexandre Bouquet
- Service d'Hématologie Biologique, Centre de Biologie Pathologie, Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - Veronique Baccini
- Laboratoire d'Hématologie, Hôpital La Timone, Marseille, France.,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France
| | - Marie-Christine Alessi
- Laboratoire d'Hématologie, Hôpital La Timone, Marseille, France.,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France
| | - Annick Ankri
- Assistance Publique-Hôpitaux de Paris, Laboratoire d'Hématologie, La Pitié Salpetrière, Paris, France
| | - Anne Bauters
- Centre de Compétence Nord-Est des Pathologies Plaquettaires (CCPP), Nancy, France.,Service d'Hématologie Biologique, Centre de Biologie Pathologie, Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - Sophie Bayart
- Centre Régional de Traitement des Hémophiles, Centre Hospitalier Universitaire de Rennes, Rennes, France
| | | | - Sylvie Daliphard
- Laboratoire d'Hématologie, Centre Hospitalier Universitaire Robert Debré, Reims, France
| | - Marie-Joelle Mozziconacci
- Département de Biopathologie, Institut Paoli-Calmettes, Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Aline Renneville
- Service d'Hématologie Biologique, Centre de Biologie Pathologie, Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - Paola Ballerini
- Assistance Publique-Hôpitaux de Paris, Département d'Hématologie, Hôpital Armand Trousseau, Paris, France.,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France
| | - Guy Leverger
- Assistance Publique-Hôpitaux de Paris, Département d'Hématologie, Hôpital Armand Trousseau, Paris, France.,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France
| | - Hagay Sobol
- Département de Biopathologie, Institut Paoli-Calmettes, Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Philippe Jonveaux
- Laboratoire de Génétique, Centre Hospitalier Universitaire de Nancy, Nancy, France
| | - Claude Preudhomme
- Service d'Hématologie Biologique, Centre de Biologie Pathologie, Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - Paquita Nurden
- Laboratoire d'Hématologie, Hôpital La Timone, Marseille, France.,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France
| | - Thomas Lecompte
- Service d'Hématologie, Hôpitaux Universitaires de Genève, Geneva, Switzerland.,Faculté de Médecine, Université de Genève, Geneva, Switzerland
| | - Remi Favier
- Assistance Publique-Hôpitaux de Paris, Département d'Hématologie, Hôpital Armand Trousseau, Paris, France. .,Inserm U1170, Villejuif, France. .,Centre de Référence des Pathologies Plaquettaires (CRPP), Hôpital La Timone, Marseille, France. .,Service d'Hématologie Biologique, Hôpital d'enfants Armand Trousseau, 26 Avenue du Dr Netter, 75012, Paris, France.
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27
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Norman JE, Lee KR, Walker ME, Murden SL, Harris J, Mundell S, J Murphy G, Mumford AD. Low multiple electrode aggregometry platelet responses are not associated with non-synonymous variants in G-protein coupled receptor genes. Thromb Res 2015; 136:818-24. [PMID: 26297398 DOI: 10.1016/j.thromres.2015.08.005] [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: 05/08/2015] [Revised: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Multiple electrode aggregometry (MEA) improves prediction of thrombosis and bleeding in cardiac patients. However, the causes of inter-individual variation in MEA results are incompletely understood. We explore whether low MEA results are associated with platelet G-protein coupled receptor (GPCR) gene variants. METHODS The effects of P2Y12 receptor (P2Y12), thromboxane A2 receptor (TPα) and protease-activated receptor 1 (PAR1) dysfunction on the MEA ADP-test, ASPI-test and TRAP-test were determined using receptor antagonists. Cardiac surgery patients with pre-operative MEA results suggesting GPCR dysfunction were selected for P2Y12 (P2RY12), TPα (TBXA2R) and PAR1 (F2R) sequencing. RESULTS In control blood samples, P2Y12, TPα or PAR1 antagonists markedly reduced ADP-test, ASPI-test and TRAP-test results respectively. In the 636 patients from a cohort of 2388 cardiac surgery patients who were not receiving aspirin or a P2Y12 blocker, the median ADP-test result was 75.1 U (range 4.8-153.2), ASPI-test 83.7 U (1.4-157.3) and TRAP-test 117.7 U (2.4-194.1), indicating a broad range of results unexplained by anti-platelet drugs. In 238 consenting patients with unexplained low MEA results, three P2RY12 variants occurred in 70/107 (65%) with suspected P2Y12 dysfunction and four TBXA2R variants occurred in 19/22 (86%) with suspected TPα dysfunction although the later group was too small to draw meaningful conclusions about variant frequency. All the variants were synonymous and unlikely to cause GPCR dysfunction. There were no F2R variants in the 109 cases with suspected PAR1 dysfunction. CONCLUSION MEA results suggesting isolated platelet GPCR dysfunction were common in cardiac surgery patients, but were not associated with non-synonymous variants in P2RY12 or F2R.
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Affiliation(s)
- Jane E Norman
- School of Clinical Sciences, University of Bristol, Bristol, UK.
| | - Kurtis R Lee
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Mary E Walker
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | | | - Jessica Harris
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Stuart Mundell
- School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - Gavin J Murphy
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Andrew D Mumford
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
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28
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Dovlatova N. Current status and future prospects for platelet function testing in the diagnosis of inherited bleeding disorders. Br J Haematol 2015; 170:150-61. [PMID: 25920378 DOI: 10.1111/bjh.13405] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Platelets play a crucial role in haemostasis by preventing bleeding at the site of vascular injury. Several defects in platelet morphology and function have been identified and described over the years. Although a range of methodologies is available to assess platelet function, a significant proportion of subjects with bleeding symptoms and normal coagulation parameters still appear to have normal results on platelet function testing. This might suggest that the reason for bleeding is multifactorial and is due to a combination of several minor defects in platelet function and/or other parts of the haemostatic system or might indicate that the currently available platelet function tests do not provide optimal diagnostic power. This review will summarize the established platelet function tests used for diagnosing inherited platelet abnormalities in adults and children, and discuss the newly developed methodologies as well as unmet challenges and potential areas for further improvement in this field.
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Affiliation(s)
- Natalia Dovlatova
- Division of Clinical Neuroscience, Thrombosis and Haemostasis Research Group, Queens Medical Centre, University of Nottingham, Nottingham, UK
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29
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Leo VC, Morgan NV, Bem D, Jones ML, Lowe GC, Lordkipanidzé M, Drake S, Simpson MA, Gissen P, Mumford A, Watson SP, Daly ME. Use of next-generation sequencing and candidate gene analysis to identify underlying defects in patients with inherited platelet function disorders. J Thromb Haemost 2015; 13:643-50. [PMID: 25556537 PMCID: PMC4383639 DOI: 10.1111/jth.12836] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 12/14/2014] [Indexed: 12/22/2022]
Abstract
BACKGROUND Inherited platelet function disorders (PFDs) are heterogeneous, and identification of the underlying genetic defects is difficult when based solely on phenotypic and clinical features of the patient. OBJECTIVE To analyze 329 genes regulating platelet function, number, and size in order to identify candidate gene defects in patients with PFDs. PATIENTS/METHODS Targeted analysis of candidate PFD genes was undertaken after next-generation sequencing of exomic DNA from 18 unrelated index cases with PFDs who were recruited into the UK Genotyping and Phenotyping of Platelets (GAPP) study and diagnosed with platelet abnormalities affecting either Gi signaling (n = 12) or secretion (n = 6). The potential pathogenicity of candidate gene defects was assessed using computational predictive algorithms. RESULTS Analysis of the 329 candidate PFD genes identified 63 candidate defects, affecting 40 genes, among index cases with Gi signaling abnormalities, while 53 defects, within 49 genes, were identified among patients with secretion abnormalities. Homozygous gene defects were more commonly associated with secretion abnormalities. Functional annotation analysis identified distinct gene clusters in the two patient subgroups. Thirteen genes with significant annotation enrichment for 'intracellular signaling' harbored 16 of the candidate gene defects identified in nine index cases with Gi signaling abnormalities. Four gene clusters, representing 14 genes, with significantly associated gene ontology annotations were identified among the cases with secretion abnormalities, the most significant association being with 'establishment of protein localization.' CONCLUSION Our findings demonstrate the genetic complexity of PFDs and highlight plausible candidate genes for targeted analysis in patients with platelet secretion and Gi signaling abnormalities.
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Affiliation(s)
- V C Leo
- Department of Cardiovascular Science, University of Sheffield Medical School, University of Sheffield, Sheffield, UK
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Ferrari D, Vitiello L, Idzko M, la Sala A. Purinergic signaling in atherosclerosis. Trends Mol Med 2015; 21:184-92. [PMID: 25637413 DOI: 10.1016/j.molmed.2014.12.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 11/19/2014] [Accepted: 12/19/2014] [Indexed: 12/28/2022]
Abstract
Cell surface expression of specific receptors and ecto-nucleotidases makes extracellular nucleotides such as ATP, ADP, UTP, and adenosine suitable as signaling molecules for physiological and pathological events, including tissue stress and damage. Recent data have revealed the participation of purinergic signaling in atherosclerosis, depicting a scenario in which, in addition to some exceptions reflecting dual effects of individual receptor subtypes, adenosine and most P1 receptors, as well as ecto-nucleotidases, show a protective, anti-atherosclerotic function. By contrast, P2 receptors promote atherosclerosis. In consideration of these findings, modulation of purinergic signaling would represent an innovative and valuable tool to counteract atherosclerosis. We summarize recent developments on the participation of the purinergic network in atheroma formation and evolution.
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Affiliation(s)
- Davide Ferrari
- Department of Life Sciences and Biotechnology, Biotechnology Centre, University of Ferrara, 44121 Ferrara, Italy.
| | - Laura Vitiello
- Laboratory of Molecular and Cellular Immunology, Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS), San Raffaele Pisana, 00166 Rome, Italy
| | - Marco Idzko
- Department of Pneumology, Freiburg University Medical Center, Albert-Ludwigs-University, Freiburg, Germany
| | - Andrea la Sala
- Laboratory of Molecular and Cellular Immunology, Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS), San Raffaele Pisana, 00166 Rome, Italy
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31
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Jones ML, Norman JE, Morgan NV, Mundell SJ, Lordkipanidzé M, Lowe GC, Daly ME, Simpson MA, Drake S, Watson SP, Mumford AD. Diversity and impact of rare variants in genes encoding the platelet G protein-coupled receptors. Thromb Haemost 2015; 113:826-37. [PMID: 25567036 PMCID: PMC4510585 DOI: 10.1160/th14-08-0679] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 11/13/2014] [Indexed: 12/20/2022]
Abstract
Platelet responses to activating agonists are influenced by common population variants within or near G protein-coupled receptor (GPCR) genes that affect receptor activity. However, the impact of rare GPCR gene variants is unknown. We describe the rare single nucleotide variants (SNVs) in the coding and splice regions of 18 GPCR genes in 7,595 exomes from the 1,000-genomes and Exome Sequencing Project databases and in 31 cases with inherited platelet function disorders (IPFDs). In the population databases, the GPCR gene target regions contained 740 SNVs (318 synonymous, 410 missense, 7 stop gain and 6 splice region) of which 70 % had global minor allele frequency (MAF) < 0.05 %. Functional annotation using six computational algorithms, experimental evidence and structural data identified 156/740 (21 %) SNVs as potentially damaging to GPCR function, most commonly in regions encoding the transmembrane and C-terminal intracellular receptor domains. In 31 index cases with IPFDs (Gi-pathway defect n=15; secretion defect n=11; thromboxane pathway defect n=3 and complex defect n=2) there were 256 SNVs in the target regions of 15 stimulatory platelet GPCRs (34 unique; 12 with MAF< 1 % and 22 with MAF≥ 1 %). These included rare variants predicting R122H, P258T and V207A substitutions in the P2Y12 receptor that were annotated as potentially damaging, but only partially explained the platelet function defects in each case. Our data highlight that potentially damaging variants in platelet GPCR genes have low individual frequencies, but are collectively abundant in the population. Potentially damaging variants are also present in pedigrees with IPFDs and may contribute to complex laboratory phenotypes.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Andrew D Mumford
- Dr. A. D. Mumford, University of Bristol, Level 7 Bristol Royal Infirmary, Bristol, BS2 8HW, United Kingdom, Tel.: +44 117 3423152, Fax: +44 117 3424036, E-mail
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van Geffen JP, Kleinegris MC, Verdoold R, Baaten CCFMJ, Cosemans JMEM, Clemetson KJ, Ten Cate H, Roest M, de Laat B, Heemskerk JWM. Normal platelet activation profile in patients with peripheral arterial disease on aspirin. Thromb Res 2015; 135:513-20. [PMID: 25600441 DOI: 10.1016/j.thromres.2014.12.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 12/22/2014] [Accepted: 12/30/2014] [Indexed: 02/05/2023]
Abstract
BACKGROUND Peripheral arterial disease (PAD) is a progressive vascular disease associated with a high risk of cardiovascular morbidity and death. Antithrombotic prevention is usually applied by prescribing the antiplatelet agent aspirin. However, in patients with PAD aspirin fails to provide protection against myocardial infarction and death, only reducing the risk of ischemic stroke. Platelets may play a role in disease development, but this has not been tested by proper mechanistic studies. In the present study, we performed a systematic evaluation of platelet reactivity in whole blood from patients with PAD using two high-throughput assays, i.e. multi-agonist testing of platelet activation by flow cytometry and multi-parameter testing of thrombus formation on spotted microarrays. METHODS Blood was obtained from 40 patients (38 on aspirin) with PAD in majority class IIa/IIb and from 40 age-matched control subjects. Whole-blood flow cytometry and multiparameter thrombus formation under high-shear flow conditions were determined using recently developed and validated assays. RESULTS Flow cytometry of whole blood samples from aspirin-treated patients demonstrated unchanged high platelet responsiveness towards ADP, slightly elevated responsiveness after glycoprotein VI stimulation, and decreased responsiveness after PAR1 thrombin receptor stimulation, compared to the control subjects. Most parameters of thrombus formation under flow were similarly high for the patient and control groups. However, in vitro aspirin treatment caused a marked reduction in thrombus formation, especially on collagen surfaces. When compared per subject, markers of ADP- and collagen-induced integrin activation (flow cytometry) strongly correlated with parameters of collagen-dependent thrombus formation under flow, indicative of a common, subject-dependent regulation of both processes. CONCLUSION Despite of the use of aspirin, most platelet activation properties were in the normal range in whole-blood from class II PAD patients. These data underline the need for more effective antithrombotic pharmacoprotection in PAD.
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Affiliation(s)
- Johanna P van Geffen
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Marie-Claire Kleinegris
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Remco Verdoold
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Constance C F M J Baaten
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Judith M E M Cosemans
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Kenneth J Clemetson
- Department of Haematology, Inselspital, University of Bern, CH-3010 Bern, Switzerland
| | - Hugo Ten Cate
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Mark Roest
- Department of Clinical Chemistry and Haematology, University Medical Centre, Utrecht The Netherlands; Synapse B.V., Maastricht University, Maastricht, The Netherlands
| | - Bas de Laat
- Synapse B.V., Maastricht University, Maastricht, The Netherlands
| | - Johan W M Heemskerk
- Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, Maastricht, The Netherlands.
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Norman JE, Westbury SK, Jones ML, Mumford AD. How should we test for nonsevere heritable platelet function disorders? Int J Lab Hematol 2014; 36:326-33. [DOI: 10.1111/ijlh.12211] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 02/12/2014] [Indexed: 11/30/2022]
Affiliation(s)
- J. E. Norman
- School of Clinical Sciences; University of Bristol; Bristol UK
| | - S. K. Westbury
- School of Clinical Sciences; University of Bristol; Bristol UK
| | - M. L. Jones
- School of Cellular and Molecular Medicine; University of Bristol; Bristol UK
| | - A. D. Mumford
- School of Cellular and Molecular Medicine; University of Bristol; Bristol UK
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34
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Daly ME, Leo VC, Lowe GC, Watson SP, Morgan NV. What is the role of genetic testing in the investigation of patients with suspected platelet function disorders? Br J Haematol 2014; 165:193-203. [DOI: 10.1111/bjh.12751] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Martina E. Daly
- Department of Cardiovascular Science; University of Sheffield Medical School; University of Sheffield; Sheffield UK
| | - Vincenzo C. Leo
- Department of Cardiovascular Science; University of Sheffield Medical School; University of Sheffield; Sheffield UK
| | - Gillian C. Lowe
- Centre for Cardiovascular Sciences; School of Clinical and Experimental Medicine; College of Medical and Dental Sciences; University of Birmingham; Birmingham UK
| | - Steve P. Watson
- Centre for Cardiovascular Sciences; School of Clinical and Experimental Medicine; College of Medical and Dental Sciences; University of Birmingham; Birmingham UK
| | - Neil V. Morgan
- Centre for Cardiovascular Sciences; School of Clinical and Experimental Medicine; College of Medical and Dental Sciences; University of Birmingham; Birmingham UK
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35
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Abstract
Platelet function tests have been traditionally used to aid in the diagnosis and management of patients with bleeding problems. Given the role of platelets in atherothrombosis, several dedicated platelet function instruments are now available that are simple to use and can be used as point-of-care assays. These can provide rapid assessment of platelet function within whole blood without the requirement of sample processing. Some tests can be used to monitor antiplatelet therapy and assess risk of bleeding and thrombosis, although current guidelines advise against this. This article discusses the potential utility of tests/instruments that are available.
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Affiliation(s)
- Paul Harrison
- School of Immunity and Infection, University of Birmingham Medical School, Birmingham, UK.
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36
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Guéguen P, Rouault K, Chen JM, Raguénès O, Fichou Y, Hardy E, Gobin E, Pan-petesch B, Kerbiriou M, Trouvé P, Marcorelles P, Abgrall JF, Le Maréchal C, Férec C. A missense mutation in the alpha-actinin 1 gene (ACTN1) is the cause of autosomal dominant macrothrombocytopenia in a large French family. PLoS One 2013; 8:e74728. [PMID: 24069336 PMCID: PMC3775762 DOI: 10.1371/journal.pone.0074728] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 08/02/2013] [Indexed: 11/29/2022] Open
Abstract
Inherited thrombocytopenia is a heterogeneous group of disorders characterized by a reduced number of blood platelets. Despite the identification of nearly 20 causative genes in the past decade, approximately half of all subjects with inherited thrombocytopenia still remain unexplained in terms of the underlying pathogenic mechanisms. Here we report a six-generation French pedigree with an autosomal dominant mode of inheritance and the identification of its genetic basis. Of the 55 subjects available for analysis, 26 were diagnosed with isolated macrothrombocytopenia. Genome-wide linkage analysis mapped a 10.9 Mb locus to chromosome 14 (14q22) with a LOD score of 7.6. Candidate gene analysis complemented by targeted next-generation sequencing identified a missense mutation (c.137GA; p.Arg46Gln) in the alpha-actinin 1 gene (ACTN1) that segregated with macrothrombocytopenia in this large pedigree. The missense mutation occurred within actin-binding domain of alpha-actinin 1, a functionally critical domain that crosslinks actin filaments into bundles. The evaluation of cultured mutation-harboring megakaryocytes by electron microscopy and the immunofluorescence examination of transfected COS-7 cells suggested that the mutation causes disorganization of the cellular cytoplasm. Our study concurred with a recently published whole-exome sequence analysis of six small Japanese families with congenital macrothrombocytopenia, adding ACTN1 to the growing list of thrombocytopenia genes.
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Affiliation(s)
- Paul Guéguen
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Laboratoire de Génétique Moléculaire et d’Histocompatibilité, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
- * E-mail:
| | - Karen Rouault
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Laboratoire de Génétique Moléculaire et d’Histocompatibilité, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
| | - Jian-Min Chen
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Cavale Blanche, Brest, France
| | - Odile Raguénès
- Laboratoire de Génétique Moléculaire et d’Histocompatibilité, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
| | - Yann Fichou
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Cavale Blanche, Brest, France
| | - Elisabeth Hardy
- Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Cavale Blanche, Brest, France
| | - Eric Gobin
- Etablissement Français du sang (EFS) – Bretagne, Brest, France
| | - Brigitte Pan-petesch
- Service d’Anatomie Pathologique, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
| | - Mathieu Kerbiriou
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
| | - Pascal Trouvé
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
| | - Pascale Marcorelles
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Etablissement Français du sang (EFS) – Bretagne, Brest, France
| | - Jean-francois Abgrall
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Service d’Anatomie Pathologique, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
| | - Cédric Le Maréchal
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Laboratoire de Génétique Moléculaire et d’Histocompatibilité, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
- Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Cavale Blanche, Brest, France
| | - Claude Férec
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1078, Brest, France
- Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale (UBO), Brest, France
- Laboratoire de Génétique Moléculaire et d’Histocompatibilité, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Morvan, Brest, France
- Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) Brest, Hôpital Cavale Blanche, Brest, France
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Off-target effect of the Epac agonist 8-pCPT-2'-O-Me-cAMP on P2Y12 receptors in blood platelets. Biochem Biophys Res Commun 2013; 437:603-8. [PMID: 23850619 DOI: 10.1016/j.bbrc.2013.07.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 07/02/2013] [Indexed: 11/21/2022]
Abstract
The primary target of the cAMP analogue 8-pCPT-2'-O-Me-cAMP is exchange protein directly activated by cAMP (Epac). Here we tested potential off-target effects of the Epac activator on blood platelet activation signalling. We found that the Epac analogue 8-pCPT-2'-O-Me-cAMP inhibits agonist-induced-GPCR-stimulated, but not collagen-stimulated, P-selectin surface expression on Epac1 deficient platelets. In human platelets, 8-pCPT-2'-O-Me-cAMP inhibited P-selectin expression elicited by the PKC activator PMA. This effect was abolished in the presence of the extracellular ADP scavenger system CP/CPK. In silico modelling of 8-pCPT-2'O-Me-cAMP binding into the purinergic platelet receptor P2Y12 revealed that the analogue docks similar to the P2Y12 antagonist 2MeSAMP. The 8-pCPT-2'-O-Me-cAMP analogue per se, did not provoke Rap 1 (Rap 1-GTP) activation or phosphorylation on the vasodilator-stimulated phosphoprotein (VASP) at Ser-157. In addition, the protein kinase A (PKA) antagonists Rp-cAMPS and Rp-8-Br-cAMPS failed to block the inhibitory effect of 8-pCPT-2'-O-Me-cAMP on thrombin- and TRAP-induced Rap 1 activation, thus suggesting that PKA is not involved. We conclude that the 8-pCPT-2'-O-Me-cAMP analogue is able to inhibit agonist-induced-GPCR-stimulated P-selectin independent from Epac1; the off-target effect of the analogue appears to be mediated by antagonistic P2Y12 receptor binding. This has implications when using cAMP analogues on specialised system involving such receptors. We found, however that the Epac agonist 8-Br-2'-O-Me-cAMP did not affect platelet activation at similar concentrations.
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Key Words
- (Rp)-adenosine-3′,5′-cyclic monophosphorothioate, Rp-isomer
- (β-phenyl-1), N(2)-etheno-8-bromoguanosine-3′,5′-cyclic monophosphate
- 2-methylthio-adenosine diphosphate
- 2-methylthio-adenosine monophosphate
- 2MeSADP
- 2MeSAMP
- 5,6-dichloro-1-β-d-ribofuranosylbenzimidazole-3′,5′-cyclic monophosphorothioate, Sp-isomer
- 8-(4-chlorophenylthio)-2′-O-methyladenosine-3′,5′-cyclic monophosphate
- 8-(4-chlorophenylthio)-2′-O-methyladenosine-3′,5′-cyclic monophosphorothioate, Sp-isomer
- 8-Br-PET-cGMP
- 8-bromoadenosineadenosine-3′,5′-cyclic monophosphorothioate, Rp-isomer
- 8-pCPT-2′-O-Me-cAMP
- ADP
- Blood platelets
- CP/CPK
- Epac
- P2Y(12) receptor
- PI3K
- PKA
- PKG
- PMA
- Rp-8-Br-cAMPS
- Rp-cAMPS
- Sp-5, 6-DCL-cBIMPS
- Sp-8-pCPT-2′-O-Me-cAMPS
- Thromboxane
- TxA(2)
- adenosine diphosphate
- cAMP
- cAMP-activated protein kinase
- cGMP-activated protein kinase
- creatine phosphate/creatine phosphokinase
- cyclic adenosine monophosphate
- exchange factor directly activated by cAMP
- phorbol 12-myristate 13-acetate
- phosphatidyl-inositol-3 kinase
- thromboxane receptor A(2)
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Watson SP, Lowe GC, Lordkipanidzé M, Morgan NV. Genotyping and phenotyping of platelet function disorders. J Thromb Haemost 2013; 11 Suppl 1:351-63. [PMID: 23516995 DOI: 10.1111/jth.12199] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The majority of patients with platelet function disorders (PFDs) have normal platelet counts and mild day-to-day bleeding symptoms, but are at risk of major hemorrhage at times of trauma, surgery, or childbirth. This group is challenging to investigate, because the assays are often time-intensive and labour-intensive, and interpretation is difficult, especially in patients with mild disorders. In addition, interuser variability in performance of the assays, including the currently accepted gold standard, light transmission aggregometry, makes the results difficult to compare between laboratories. Furthermore, a similar pattern of mucocutaneous bleeding is seen in disorders in other components of the hemostatic pathway, including type 1 von Willebrand disease (VWD). We have undertaken an extensive investigation of patients with clinically diagnosed excessive bleeding, using a genotyping and platelet phenotyping approach based on lumi-aggregometry, and other specialist tests of platelet function, in combination with Sanger and next-generation sequencing (NGS). We found a functional defect in ~ 60% of patients, the majority being associated with feedback pathways of platelet activation. Function-disrupting mutations were identified in known and novel genes, and coinheritance with other genetic disorders of hemostasis, including type 1 VWD, was shown. A significant number of mutations are heterozygous and unlikely to cause extensive bleeding in isolation, consistent with incomplete penetrance of inheritance of bleeding disorders and a multifactorial etiology for excessive bleeding in many patients. Mucocutaneous bleeding is a complex trait, and this has important implications for NGS in the assessment of a PFD.
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Affiliation(s)
- S P Watson
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
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van der Meijden PEJ, Bouman AC, Feijge MAH, van Oerle R, Spronk HMH, Hamulyák K, ten Cate-Hoek AJ, ten Cate H, Heemskerk JWM. Platelet dysfunction in thrombosis patients treated with vitamin K antagonists and recurrent bleeding. PLoS One 2013; 8:e64112. [PMID: 23724024 PMCID: PMC3665853 DOI: 10.1371/journal.pone.0064112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 04/10/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Recurrent bleeding can complicate the treatment of thrombosis patients with vitamin K antagonists (VKA), even at a well-regulated level of anticoagulation. In this proof-of-principle study, we investigated whether alterations in platelet function or von Willebrand factor (vWf) contribute to a bleeding phenotype in these patients. METHODS In this case-control study 33 well-regulated patients without bleeding events (controls) and 33 patients with recurrent bleeding (cases) were retrospectively included. Thrombin generation and vWf were determined in plasma. Platelet function was assessed by light transmission aggregometry and flow cytometry using a validated panel of agonists. RESULTS Thrombin generation was similarly reduced in controls and cases, in comparison to normal plasma. Plasma vWf level was above the normal range in 85% of controls and 67% of the cases. vWf activity was similarly increased in all patients in comparison to healthy volunteers. Platelet aggregation was in the normal range for almost all patients irrespective of the type of agonist. However, in response to a low collagen dose, platelets from 21% of controls and 27% of cases showed diminished responses. Agonist-induced secretion of alpha- and dense-granules or integrin αIIbβ3 activation were affected in platelets from neither controls nor cases. CONCLUSION Recurrent bleeding in well-controlled patients on VKA therapy is not explained by anti-hemostatic changes in platelet or vWf function.
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Affiliation(s)
- Paola E J van der Meijden
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center, Maastricht, The Netherlands.
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A method for positive and negative selection of Plasmodium falciparum platelet-mediated clumping parasites and investigation of the role of CD36. PLoS One 2013; 8:e55453. [PMID: 23405153 PMCID: PMC3566186 DOI: 10.1371/journal.pone.0055453] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 12/29/2012] [Indexed: 01/08/2023] Open
Abstract
Platelet-mediated clumping of Plasmodium falciparum infected erythrocytes (IEs) is a frequently observed parasite adhesion phenotype. The importance of clumping in severe malaria and the molecular mechanisms behind this phenomenon are incompletely understood. Three platelet surface molecules have previously been identified as clumping receptors: CD36, globular C1q receptor (gC1qR/HABP1/p32), and P-selectin (CD62P), but the parasite ligands mediating this phenotype are unknown. The aim of this work was to develop a selection method to facilitate investigations of the molecular mechanisms of clumping in selected P. falciparum lines. Magnetic beads coated with anti-platelet antibodies were used to positively and negatively select clumping IEs from P. falciparum strains IT, HB3, 3D7 and Dd2. Clumping in all four positively selected parasite lines was abolished by antibodies to CD36, but was not affected by antibodies to gC1qR or P-selectin. Clumping positive lines showed significantly higher binding to CD36 than clumping negative lines in flow adhesion assays (strains IT, HB3 and 3D7, p<0.05 for all strains, paired t test) and static assays (strain Dd2, p<0.0001 paired t test). However, clumping negative lines IT, HB3 and 3D7 did show some binding to CD36 under flow conditions, indicating that CD36-binding is not sufficient for clumping. These data show that CD36-dependent clumping positive and negative lines can easily be selected from P. falciparum laboratory strains. CD36-binding is necessary but not sufficient for clumping, and the molecular differences between clumping positive and negative parasite lines responsible for the phenotype require further investigation.
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Hughes CE, Radhakrishnan UP, Lordkipanidzé M, Egginton S, Dijkstra JM, Jagadeeswaran P, Watson SP. G6f-like is an ITAM-containing collagen receptor in thrombocytes. PLoS One 2012; 7:e52622. [PMID: 23285115 PMCID: PMC3528668 DOI: 10.1371/journal.pone.0052622] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 11/20/2012] [Indexed: 01/22/2023] Open
Abstract
Collagen activates mammalian platelets through a complex of the immunoglobulin (Ig) receptor GPVI and the Fc receptor γ-chain, which has an immunoreceptor tyrosine-based activation motif (ITAM). Cross-linking of GPVI mediates activation through the sequential activation of Src and Syk family kinases and activation of PLCγ2. Nucleated thrombocytes in fish are activated by collagen but lack an ortholog of GPVI. In this study we show that collagen activates trout thrombocytes in whole blood and under flow conditions through a Src kinase driven pathway. We identify the Ig receptor G6f-like as a collagen receptor and demonstrate in a cell line assay that it signals through its cytoplasmic ITAM. Using a morpholino for in vivo knock-down of G6f-like levels in zebrafish, we observed a marked delay or absence of occlusion of the venous and arterial systems in response to laser injury. Thus, G6f-like is a physiologically relevant collagen receptor in fish thrombocytes which signals through the same ITAM-based signalling pathway as mammalian GPVI, providing a novel example of convergent evolution.
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Affiliation(s)
- Craig E Hughes
- Centre for Cardiovascular Sciences, Institute for Biomedical Research, The College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom.
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Dawood BB, Lowe GC, Lordkipanidzé M, Bem D, Daly ME, Makris M, Mumford A, Wilde JT, Watson SP. Evaluation of participants with suspected heritable platelet function disorders including recommendation and validation of a streamlined agonist panel. Blood 2012; 120:5041-9. [PMID: 23002116 PMCID: PMC3790949 DOI: 10.1182/blood-2012-07-444281] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 09/12/2012] [Indexed: 11/20/2022] Open
Abstract
Light transmission aggregometry (LTA) is used worldwide for the investigation of heritable platelet function disorders (PFDs), but interpretation of results is complicated by the feedback effects of ADP and thromboxane A(2) (TxA(2)) and by the overlap with the response of healthy volunteers. Over 5 years, we have performed lumi-aggregometry on 9 platelet agonists in 111 unrelated research participants with suspected PFDs and in 70 healthy volunteers. Abnormal LTA or ATP secretion test results were identified in 58% of participants. In 84% of these, the patterns of response were consistent with defects in Gi receptor signaling, the TxA(2) pathway, and dense granule secretion. Participants with defects in signaling to Gq-coupled receptor agonists and to collagen were also identified. Targeted genotyping identified 3 participants with function-disrupting mutations in the P2Y(12) ADP and TxA(2) receptors. The results of the present study illustrate that detailed phenotypic analysis using LTA and ATP secretion is a powerful tool for the diagnosis of PFDs. Our data also enable subdivision at the level of platelet-signaling pathways and in some cases to individual receptors. We further demonstrate that most PFDs can be reliably diagnosed using a streamlined panel of key platelet agonists and specified concentrations suitable for testing in most clinical diagnostic laboratories.
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Affiliation(s)
- Ban B Dawood
- Department of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom.
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43
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Gleim S, Stitham J, Tang WH, Martin KA, Hwa J. An eicosanoid-centric view of atherothrombotic risk factors. Cell Mol Life Sci 2012; 69:3361-80. [PMID: 22491820 PMCID: PMC3691514 DOI: 10.1007/s00018-012-0982-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 03/22/2012] [Accepted: 03/26/2012] [Indexed: 02/06/2023]
Abstract
Cardiovascular disease is the foremost cause of morbidity and mortality in the Western world. Atherosclerosis followed by thrombosis (atherothrombosis) is the pathological process underlying most myocardial, cerebral, and peripheral vascular events. Atherothrombosis is a complex and heterogeneous inflammatory process that involves interactions between many cell types (including vascular smooth muscle cells, endothelial cells, macrophages, and platelets) and processes (including migration, proliferation, and activation). Despite a wealth of knowledge from many recent studies using knockout mouse and human genetic studies (GWAS and candidate approach) identifying genes and proteins directly involved in these processes, traditional cardiovascular risk factors (hyperlipidemia, hypertension, smoking, diabetes mellitus, sex, and age) remain the most useful predictor of disease. Eicosanoids (20 carbon polyunsaturated fatty acid derivatives of arachidonic acid and other essential fatty acids) are emerging as important regulators of cardiovascular disease processes. Drugs indirectly modulating these signals, including COX-1/COX-2 inhibitors, have proven to play major roles in the atherothrombotic process. However, the complexity of their roles and regulation by opposing eicosanoid signaling, have contributed to the lack of therapies directed at the eicosanoid receptors themselves. This is likely to change, as our understanding of the structure, signaling, and function of the eicosanoid receptors improves. Indeed, a major advance is emerging from the characterization of dysfunctional naturally occurring mutations of the eicosanoid receptors. In light of the proven and continuing importance of risk factors, we have elected to focus on the relationship between eicosanoids and cardiovascular risk factors.
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Affiliation(s)
- Scott Gleim
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511
| | - Jeremiah Stitham
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511
| | - Wai Ho Tang
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511
| | - Kathleen A. Martin
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511
| | - John Hwa
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06511
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Harrison P, Mackie I, Mumford A, Briggs C, Liesner R, Winter M, Machin S. Guidelines for the laboratory investigation of heritable disorders of platelet function. Br J Haematol 2011; 155:30-44. [DOI: 10.1111/j.1365-2141.2011.08793.x] [Citation(s) in RCA: 254] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Armstrong PC, Kirkby NS, Zain ZN, Emerson M, Mitchell JA, Warner TD. Thrombosis is reduced by inhibition of COX-1, but unaffected by inhibition of COX-2, in an acute model of platelet activation in the mouse. PLoS One 2011; 6:e20062. [PMID: 21629780 PMCID: PMC3100333 DOI: 10.1371/journal.pone.0020062] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Accepted: 04/24/2011] [Indexed: 01/03/2023] Open
Abstract
Background Clinical use of selective inhibitors of cyclooxygenase (COX)-2 appears associated with increased risk of thrombotic events. This is often hypothesised to reflect reduction in anti-thrombotic prostanoids, notably PGI2, formed by COX-2 present within endothelial cells. However, whether COX-2 is actually expressed to any significant extent within endothelial cells is controversial. Here we have tested the effects of acute inhibition of COX on platelet reactivity using a functional in vivo approach in mice. Methodology/Principal Findings A non-lethal model of platelet-driven thromboembolism in the mouse was used to assess the effects of aspirin (7 days orally as control) diclofenac (1 mg.kg−1, i.v.) and parecoxib (0.5 mg.kg−1, i.v.) on thrombus formation induced by collagen or the thromboxane (TX) A2-mimetic, U46619. The COX inhibitory profiles of the drugs were confirmed in mouse tissues ex vivo. Collagen and U46619 caused in vivo thrombus formation with the former, but not latter, sensitive to oral dosing with aspirin. Diclofenac inhibited COX-1 and COX-2 ex vivo and reduced thrombus formation in response to collagen, but not U46619. Parecoxib inhibited only COX-2 and had no effect upon thrombus formation caused by either agonist. Conclusions/Significance Inhibition of COX-1 by diclofenac or aspirin reduced thrombus formation induced by collagen, which is partly dependent upon platelet-derived TXA2, but not that induced by U46619, which is independent of platelet TXA2. These results are consistent with the model demonstrating the effects of COX-1 inhibition in platelets, but provide no support for the hypothesis that acute inhibition of COX-2 in the circulation increases thrombosis.
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Affiliation(s)
- Paul C. Armstrong
- The William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Nicholas S. Kirkby
- The William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- Cardiothoracic and Stem Cell Pharmacology, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Zetty N. Zain
- The William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Michael Emerson
- Platelet Biology Group, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Jane A. Mitchell
- Cardiothoracic and Stem Cell Pharmacology, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Timothy D. Warner
- The William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- * E-mail:
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Armstrong PCJ, Leadbeater PD, Chan MV, Kirkby NS, Jakubowski JA, Mitchell JA, Warner TD. In the presence of strong P2Y12 receptor blockade, aspirin provides little additional inhibition of platelet aggregation. J Thromb Haemost 2011; 9:552-61. [PMID: 21143373 PMCID: PMC3064407 DOI: 10.1111/j.1538-7836.2010.04160.x] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Aspirin and antagonists of platelet ADP P2Y(12) receptors are often coprescribed for protection against thrombotic events. However, blockade of platelet P2Y(12) receptors can inhibit thromboxane A(2) (TXA(2))-dependent pathways of platelet activation independently of aspirin. OBJECTIVES To assess in vitro whether aspirin adds additional antiaggregatory effects to strong P2Y(12) receptor blockade. METHODS With the use of platelet-rich plasma from healthy volunteers, determinations were made in 96-well plates of platelet aggregation, TXA(2) production and ADP/ATP release caused by ADP, arachidonic acid, collagen, epinephrine, TRAP-6 amide and U46619 (six concentrations of each) in the presence of prasugrel active metabolite (PAM; 0.1-10 μmol L(-1)), aspirin (30 μmol L(-1)), PAM + aspirin or vehicle. results: PAM concentration-dependently inhibited aggregation; for example, aggregation in response to all concentrations of ADP and U46619 was inhibited by ≥ 95% by PAM at > 3 μmol L(-1) . In further tests of PAM (3 μmol L(-1)), aspirin (30 μmol L(-1)) and PAM + aspirin, aspirin generally failed to produce more inhibition than PAM or additional inhibition to that caused by PAM. The antiaggregatory effects of PAM were associated with reductions in the platelet release of both TXA(2) and ATP + ADP. Similar effects were found when either citrate or lepirudin were used as anticoagulants, and when traditional light transmission aggregometry was conducted at low stirring speeds. CONCLUSIONS P2Y(12) receptors are critical to the generation of irreversible aggregation through the TXA(2) -dependent pathway. As a result, strong P2Y(12) receptor blockade alone causes inhibition of platelet aggregation that is little enhanced by aspirin. The clinical relevance of these observations remains to be determined.
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Affiliation(s)
- P C J Armstrong
- The William Harvey Research Institute, Barts & the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
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Nash CA, Séverin S, Dawood BB, Makris M, Mumford A, Wilde J, Senis YA, Watson SP. Src family kinases are essential for primary aggregation by G(i) -coupled receptors. J Thromb Haemost 2010; 8:2273-82. [PMID: 20738760 DOI: 10.1111/j.1538-7836.2010.03992.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION AND BACKGROUND Adrenaline stimulates biphasic aggregation in plasma through the G(i) -coupled α(2A) -adrenoreceptor. In the present study, we demonstrate that both primary and secondary wave aggregation induced by adrenaline in plasma is blocked by two structurally distinct inhibitors of Src family kinases, dasatinib and PD0173952. METHODS AND RESULTS In contrast, primary aggregation is partially inhibited or unaffected in the presence of inhibitors of cyclo-oxygenase, phosphoinositide (PI) 3-kinases, and P2Y(1) and P2Y(12) ADP receptors, although secondary aggregation is abolished. The ability of adrenaline to inhibit adenylyl cyclase and to synergize with platelet agonists in mediating platelet activation in plasma is retained in the presence of Src family kinase inhibition. Moreover, adrenaline does not activate Src family kinases, as determined by western blotting of their regulatory tyrosines, suggesting that constitutive signaling from Src family kinases may underlie their role in activation. Adrenaline is widely used in clinical laboratories for investigation of patients with suspected bleeding disorders. In a group of 90 unrelated patients with a clinically diagnosed platelet bleeding disorder, we identified four who did not exhibit primary wave aggregation in response to adrenaline, although the catecholamine potentiated the response to other agonists, and five who failed to undergo secondary wave aggregation. In contrast, adrenaline stimulated biphasic aggregation in 60 controls. All of the patients with a defective response to adrenaline had impaired ADP-induced platelet activation. CONCLUSIONS The present results indicate a previously unappreciated role for Src family kinases in mediating G(i) signaling in plasma, and demonstrate heterogeneity in response to adrenaline in patients with a clinically diagnosed platelet disorder.
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Affiliation(s)
- C A Nash
- Centre for Cardiovascular Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, UK.
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Hartley JL, Zachos NC, Dawood B, Donowitz M, Forman J, Pollitt RJ, Morgan NV, Tee L, Gissen P, Kahr WHA, Knisely AS, Watson S, Chitayat D, Booth IW, Protheroe S, Murphy S, de Vries E, Kelly DA, Maher ER. Mutations in TTC37 cause trichohepatoenteric syndrome (phenotypic diarrhea of infancy). Gastroenterology 2010; 138:2388-98, 2398.e1-2. [PMID: 20176027 PMCID: PMC3166659 DOI: 10.1053/j.gastro.2010.02.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Revised: 01/31/2010] [Accepted: 02/09/2010] [Indexed: 01/29/2023]
Abstract
BACKGROUND & AIMS Trichohepatoenteric syndrome (THES) is an autosomal-recessive disorder characterized by life-threatening diarrhea in infancy, immunodeficiency, liver disease, trichorrhexis nodosa, facial dysmorphism, hypopigmentation, and cardiac defects. We attempted to characterize the phenotype and elucidate the molecular basis of THES. METHODS Twelve patients with classic THES from 11 families had detailed phenotyping. Autozygosity mapping was undertaken in 8 patients from consanguineous families using 250,000 single nucleotide polymorphism arrays and linked regions evaluated using microsatellite markers. Linkage was confirmed to one region from which candidate genes were analyzed. The effect of mutations on protein production and/or localization in hepatocytes and intestinal epithelial cells from affected patients was characterized by immunohistochemistry. RESULTS Previously unrecognized platelet abnormalities (reduced platelet alpha-granules, unusual stimulated alpha granule content release, abnormal lipid inclusions, abnormal platelet canalicular system, and reduced number of microtubules) were identified. The THES locus was mapped to 5q14.3-5q21.2. Sequencing of candidate genes showed mutations in TTC37, which encodes the uncharacterized tetratricopeptide repeat protein, thespin. Bioinformatic analysis suggested thespin to be involved in protein-protein interactions or chaperone. Preliminary studies of enterocyte brush-border ion transporter proteins (sodium hydrogen exchanger 2, sodium hydrogen exchanger 3, aquaporin 7, sodium iodide symporter, and hydrogen potassium adenosine triphosphatase [ATPase]) showed reduced expression or mislocalization in all THES patients with different profiles for each. In contrast the basolateral localization of Na/K ATPase was not altered. CONCLUSIONS THES is caused by mutations in TTC37. TTC37 mutations have a multisystem effect, which may be owing to abnormal stability and/or intracellular localization of TTC37 target proteins.
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Affiliation(s)
- Jane Louise Hartley
- Department of Medical and Molecular Genetics, School of Clinical and Experimental Medicine, University of Birmingham College of Medical and Dental School, Institute of Biomedical Research, Edgbaston, Birmingham, UK.
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A novel thromboxane A2 receptor D304N variant that abrogates ligand binding in a patient with a bleeding diathesis. Blood 2009; 115:363-9. [PMID: 19828703 DOI: 10.1182/blood-2009-08-236976] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We investigated the cause of mild mucocutaneous bleeding in a 14-year-old male patient (P1). Platelet aggregation and ATP secretion induced by arachidonic acid and the thromboxane A(2) receptor (TxA(2)R) agonist U46619 were reduced in P1 compared with controls, whereas the responses to other platelet agonists were retained. P1 was heterozygous for a transversion within the TBXA2R gene predictive of a D304N substitution in the TxA(2)R. In Chinese hamster ovary-K1 cells expressing the variant D304N TxA(2)R, U46619 did not increase cytosolic free Ca(2+) concentration, indicating loss of receptor function. The TxA(2)R antagonist [(3)H]-SQ29548 showed an approximate 50% decrease in binding to platelets from P1 but absent binding to Chinese hamster ovary-K1 cells expressing variant D304N TxA(2)R. This is the second naturally occurring TxA(2)R variant to be associated with platelet dysfunction and the first in which loss of receptor function is associated with reduced ligand binding. D304 lies within a conserved NPXXY motif in transmembrane domain 7 of the TxA(2)R that is a key structural element in family A G protein-coupled receptors. Our demonstration that the D304N substitution causes clinically significant platelet dysfunction by reducing ligand binding establishes the importance of the NPXXY motif for TxA(2)R function in vivo.
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Wenham M, Grieve S, Cummins M, Jones ML, Booth S, Kilner R, Ancliff PJ, Griffiths GM, Mumford AD. Two patients with Hermansky Pudlak syndrome type 2 and novel mutations in AP3B1. Haematologica 2009; 95:333-7. [PMID: 19679886 DOI: 10.3324/haematol.2009.012286] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Hermansky Pudlak syndrome type 2 (HPS2) is a rare disorder associated with mutations in the Adaptor Protein 3 (AP-3) complex, which is involved in sorting transmembrane proteins to lysosomes and related organelles. We now report 2 unrelated subjects with HPS2 who show a characteristic clinical phenotype of oculocutaneous albinism, platelet and T-lymphocyte dysfunction and neutropenia. The subjects were homozygous for different deletions within AP3B1 (g.del180242-180866, c.del153-156), which encodes the AP-3beta3A subunit, resulting in frame shifts and introduction of nonsense substitutions (p.E693fsX13, p.E52fsX11). In the subject with p.E693fsX13, this resulted in expression of a truncated variant beta3A protein. Cytotoxic T-lymphocyte (CTL) clones from both study subjects showed increased cell-surface expression of CD63 and reduced cytotoxicity. Platelets showed impaired aggregation and reduced uptake of (3)H-serotonin. These findings are consistent with CTL granule and platelet dense granule defects, respectively. This report extends the clinical and laboratory description of HPS2.
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Affiliation(s)
- Matt Wenham
- Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge CB2 0XY, UK
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