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Su LY, Yao M, Xu W, Zhong M, Cao Y, Zhou H. Cascade encapsulation of antimicrobial peptides, exosomes and antibiotics in fibrin-gel for first-aid hemostasis and infected wound healing. Int J Biol Macromol 2024; 269:132140. [PMID: 38719006 DOI: 10.1016/j.ijbiomac.2024.132140] [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: 12/06/2023] [Revised: 04/19/2024] [Accepted: 05/05/2024] [Indexed: 05/13/2024]
Abstract
Wounding is one of the most common healthcare problems. Bioactive hydrogels have attracted much attention in first-aid hemostasis and wound healing due to their excellent biocompatibility, antibacterial properties, and pro-healing bioactivity. However, their applications are limited by inadequate mechanical properties. In this study, we first prepared edible rose-derived exosome-like nanoparticles (ELNs) and used them to encapsulate antimicrobial peptides (AMP), abbreviated as ELNs(AMP). ELNs(AMP) showed superior intracellular antibacterial activity, 2.5 times greater than AMP, in in vitro cell infection assays. We then prepared and tested an FDA-approved fibrin-gel of fibrinogen and thrombin encapsulating ELNs(AMP) and novobiocin sodium salt (NB) (ELNs(AMP)/NB-fibrin-gels). The fibrin gel showed a sustained release of ELNs(AMP) and NB over the eight days of testing. After spraying onto the skin, the formulation underwent in situ gelation and developed a stable patch with excellent hemostatic performance in a mouse liver injury model with hemostasis in 31 s, only 35.6 % of the PBS group. The fibrin gel exhibited pro-wound healing properties in the mouse-infected skin defect model. The thickness of granulation tissue and collagen of the ELNs(AMP)/NB-fibrin-gels group was 4.00, 6.32 times greater than that of the PBS group. In addition, the ELNs(AMP)/NB-fibrin-gels reduced inflammation (decreased mRNA levels of TNF-α, IL-1β, IL6, MCP1, and CXCL1) at the wound sites and demonstrated a biocompatible and biosafe profile. Thus, we have developed a hydrogel system with excellent hemostatic, antibacterial, and pro-wound healing properties, which may be a candidate for next-generation tissue regeneration with a wide clinical application for first-aid hemostasis and infected wound healing.
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Affiliation(s)
- Ling-Yan Su
- College of Food Science and Technology, Yunnan Agricultural University, No. 452 Fengyuan Road, Kunming 650000, China; Yunnan Provincial Key Laboratory of Precision Nutrition and Personalized Food Manufacturing, Yunnan Agricultural University, Kunming 650000, China
| | - Mengyu Yao
- Department of Cardiovascular Surgery, The First People's Hospital of Yunnan Province, Xishan District, No.157 Jinbi Road, Kunming 650032, China; School of Medical, Kunming University of Science and Technology, No.727 Jingming South Road, Kunming 650000, China
| | - Wen Xu
- College of Food Science and Technology, Yunnan Agricultural University, No. 452 Fengyuan Road, Kunming 650000, China
| | - Minghua Zhong
- Department of Cardiovascular Surgery, The First People's Hospital of Yunnan Province, Xishan District, No.157 Jinbi Road, Kunming 650032, China; Yunnan Key Laboratory of Innovative Application of Traditional Chinese Medicine, The First People's Hospital of Yunnan Province, Kunming 650000, China
| | - Yu Cao
- Department of Cardiovascular Surgery, The First People's Hospital of Yunnan Province, Xishan District, No.157 Jinbi Road, Kunming 650032, China; Yunnan Key Laboratory of Innovative Application of Traditional Chinese Medicine, The First People's Hospital of Yunnan Province, Kunming 650000, China.
| | - Hejiang Zhou
- College of Food Science and Technology, Yunnan Agricultural University, No. 452 Fengyuan Road, Kunming 650000, China; Yunnan Provincial Key Laboratory of Precision Nutrition and Personalized Food Manufacturing, Yunnan Agricultural University, Kunming 650000, China.
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Mansi CD, Severa JR, Wilhelm JN, Marar TT, Roberts ME, Zhao X, Stalker TJ. Dual antithrombotic therapy dose-dependently alters hemostatic plug structure and function. J Thromb Haemost 2024; 22:1016-1023. [PMID: 38142847 PMCID: PMC10960666 DOI: 10.1016/j.jtha.2023.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 11/20/2023] [Accepted: 12/11/2023] [Indexed: 12/26/2023]
Abstract
BACKGROUND Antithrombotic medications carry an inherent risk of bleeding, which may be exacerbated when anticoagulant and antiplatelet therapeutics are combined. Prior studies have shown different effects of antiplatelet vs anticoagulant drugs on the structure and function of hemostatic plugs in vivo. OBJECTIVES We examined whether dual antithrombotic treatment consisting of combined antiplatelet and anticoagulant therapeutics alters hemostatic plug structure and function differently from treatment with either therapeutic alone. METHODS Mice were treated with the P2Y12 antagonist clopidogrel and the factor Xa inhibitor rivaroxaban across a range of doses, either alone or in combination. The hemostatic response was assessed using a mouse jugular vein puncture injury model. Platelet accumulation and fibrin deposition were evaluated using quantitative multiphoton fluorescence microscopy, and bleeding times were recorded. RESULTS Mice treated with clopidogrel alone exhibited a decrease in platelet accumulation at the site of injury, with prolonged bleeding times only at the highest doses of clopidogrel used. Mice treated with rivaroxaban alone instead showed a reduction in fibrin deposition with no impact on bleeding. Mice treated with both clopidogrel and rivaroxaban exhibited platelet and fibrin accumulation that was similar to that with either drug given alone; however, dual antithrombotic therapy resulted in impaired hemostasis at doses that had no impact on bleeding when given in isolation. CONCLUSION Combined administration of antiplatelet and anticoagulant therapeutics exacerbates bleeding as compared to that with either drug alone, potentially via combined loss of both adenosine 5'-diphosphate- and thrombin-mediated platelet activation. These findings enhance our understanding of the bleeding risk associated with dual antithrombotic therapy.
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Affiliation(s)
- Christopher D Mansi
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Jenna R Severa
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Joseph N Wilhelm
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Tanya T Marar
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Meghan E Roberts
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Xuefei Zhao
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Timothy J Stalker
- Department of Medicine, Cardeza Center for Hemostasis, Thrombosis, and Vascular Biology, Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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La CC, Smith SA, Kalathottukaren MT, Haynes CA, Morrissey JH, Kizhakkedathu JN. External Trigger Free Charge Switchable Cationic Ligands in the Design of Safe and Effective Universal Heparin Antidote. Adv Healthc Mater 2024:e2400108. [PMID: 38537246 DOI: 10.1002/adhm.202400108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/06/2024] [Indexed: 04/05/2024]
Abstract
Thrombosis, the formation of blood clots within a blood vessel, can lead to severe complications including pulmonary embolism, cardiac arrest, and stroke. The most widely administered class of anticoagulants is heparin-based anticoagulants such as unfractionated heparin, low-molecular weight heparins (LMWHs), and fondaparinux. Protamine is the only FDA-approved heparin antidote. Protamine has limited efficacy neutralizing LMWHs and no reversal activity against fondaparinux. The use of protamine can lead to complications, including excessive bleeding, hypotension, and hypersensitivity, and has narrow therapeutic window. In this work, a new concept in the design of a universal heparin antidote: switchable protonation of cationic ligands, is presented. A library of macromolecular polyanion inhibitors (MPIs) is synthesized and screened to identify molecules that can neutralize all heparins with high selectivity and reduced toxicity. MPIs are developed by assembling cationic binding groups possessing switchable protonation states onto a polymer scaffold. By strategically selecting the identity and modulating the density of cationic binding groups on the polymer scaffold, a superior universal heparin reversal agent is developed with improved heparin-binding activity and increased hemocompatibility profiles leading to minimal effect on hemostasis. The activity of this heparin antidote is demonstrated using in vitro and in vivo studies.
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Affiliation(s)
- Chanel C La
- Centre for Blood Research, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Stephanie A Smith
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Manu Thomas Kalathottukaren
- Centre for Blood Research, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Charles A Haynes
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - James H Morrissey
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Jayachandran N Kizhakkedathu
- Centre for Blood Research, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
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4
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Wang Q, Qin Y, Ma J, Zhou K, Xia G, Li Y, Xie L, Afful RG, Lan Q, Huo X, Zou J, Yang H. An early warning indicator of mortality risk in patients with COVID-19: the neutrophil extracellular traps/neutrophilic segmented granulocyte ratio. Front Immunol 2024; 15:1287132. [PMID: 38348024 PMCID: PMC10859410 DOI: 10.3389/fimmu.2024.1287132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 01/15/2024] [Indexed: 02/15/2024] Open
Abstract
Background Neutrophil extracellular traps (NETs) play a key role in thrombus formation in patients with coronavirus disease 2019 (COVID-19). However, the existing detection and observation methods for NETs are limited in their ability to provide quantitative, convenient, and accurate descriptions of in situ NETs. Therefore, establishing a quantitative description of the relationship between NETs and thrombosis remains a challenge. Objective We employed morphological observations of blood cells and statistical analyses to investigate the correlation between the NETs/neutrophilic segmented granulocyte ratio and mortality risk in patients with COVID-19. Methods Peripheral blood samples were collected from 117 hospitalized patients with COVID-19 between November 2022 and February 2023, and various blood cell parameters were measured. Two types of smudge cells were observed in the blood and counted: lymphatic and neutral smudge cells. Statistical data analysis was used to establish COVID-19 mortality risk assessment indicators. Results Morphological observations of neutrophilic smudge cells revealed swelling, eruption, and NETs formation in the neutrophil nuclei. Subsequently, the NETs/neutrophilic segmented granulocyte ratio (NNSR) was calculated. A high concentration of NETs poses a fatal risk for thrombus formation in patients. Statistical analysis indicated that a high NNSR was more suitable for evaluating the risk of death in patients with COVID-19 compared to elevated fibrinogen (FIB) and D-dimer (DD) levels. Conclusion Observing blood cell morphology is an effective method for the detection of NETs, NNSR are important markers for revealing the mortality risk of patients with COVID-19.
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Affiliation(s)
- Qiong Wang
- The Affiliated Wuxi People’s Hospital of Nanjing Medical University, Wuxi People’s Hospital, Wuxi Medical Center, Nanjing Medical University, Wuxi, China
| | - Yu Qin
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jingyun Ma
- The Affiliated Wuxi People’s Hospital of Nanjing Medical University, Wuxi People’s Hospital, Wuxi Medical Center, Nanjing Medical University, Wuxi, China
| | - Kehao Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Guiping Xia
- The Affiliated Wuxi People’s Hospital of Nanjing Medical University, Wuxi People’s Hospital, Wuxi Medical Center, Nanjing Medical University, Wuxi, China
| | - Ya Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Li Xie
- School of Internet of Things Engineering, Jiangnan University, Wuxi, China
| | - Richmond Godwin Afful
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Qian Lan
- School of Internet of Things Engineering, Jiangnan University, Wuxi, China
| | - Xingyu Huo
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jian Zou
- The Affiliated Wuxi People’s Hospital of Nanjing Medical University, Wuxi People’s Hospital, Wuxi Medical Center, Nanjing Medical University, Wuxi, China
| | - Hailin Yang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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Hur WS, Kawano T, Mwiza JMN, Paul DS, Lee RH, Clark EG, Bouck EG, Dutta A, Cai C, Baker SR, Guthold M, Mackman N, Mangin P, Wolberg AS, Bergmeier W, Flick MJ. Mice expressing nonpolymerizable fibrinogen have reduced arterial and venous thrombosis with preserved hemostasis. Blood 2024; 143:105-117. [PMID: 37832029 PMCID: PMC10797557 DOI: 10.1182/blood.2023020805] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 09/06/2023] [Accepted: 09/19/2023] [Indexed: 10/15/2023] Open
Abstract
ABSTRACT Elevated circulating fibrinogen levels correlate with increased risk for both cardiovascular and venous thromboembolic diseases. In vitro studies show that formation of a highly dense fibrin matrix is a major determinant of clot structure and stability. Here, we analyzed the impact of nonpolymerizable fibrinogen on arterial and venous thrombosis as well as hemostasis in vivo using FgaEK mice that express normal levels of a fibrinogen that cannot be cleaved by thrombin. In a model of carotid artery thrombosis, FgaWT/EK and FgaEK/EK mice were protected from occlusion with 4% ferric chloride (FeCl3) challenges compared with wild-type (FgaWT/WT) mice, but this protection was lost, with injuries driven by higher concentrations of FeCl3. In contrast, fibrinogen-deficient (Fga-/-) mice showed no evidence of occlusion, even with high-concentration FeCl3 challenge. Fibrinogen-dependent platelet aggregation and intraplatelet fibrinogen content were similar in FgaWT/WT, FgaWT/EK, and FgaEK/EK mice, consistent with preserved fibrinogen-platelet interactions that support arterial thrombosis with severe challenge. In an inferior vena cava stasis model of venous thrombosis, FgaEK/EK mice had near complete protection from thrombus formation. FgaWT/EK mice also displayed reduced thrombus incidence and a significant reduction in thrombus mass relative to FgaWT/WT mice after inferior vena cava stasis, suggesting that partial expression of nonpolymerizable fibrinogen was sufficient for conferring protection. Notably, FgaWT/EK and FgaEK/EK mice had preserved hemostasis in multiple models as well as normal wound healing times after skin incision, unlike Fga-/- mice that displayed significant bleeding and delayed healing. These findings indicate that a nonpolymerizable fibrinogen variant can significantly suppress occlusive thrombosis while preserving hemostatic potential in vivo.
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Affiliation(s)
- Woosuk S. Hur
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Tomohiro Kawano
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Jean Marie N. Mwiza
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - David S. Paul
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Robert H. Lee
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Emily G. Clark
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Emma G. Bouck
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Ananya Dutta
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Can Cai
- Department of Physics, Wake Forest University, Winston-Salem, NC
| | - Stephen R. Baker
- Department of Physics, Wake Forest University, Winston-Salem, NC
| | - Martin Guthold
- Department of Physics, Wake Forest University, Winston-Salem, NC
| | - Nigel Mackman
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Pierre Mangin
- Université de Strasbourg, INSERM, EFS Grand-Est, BPPS UMR-S1255, FMTS, Strasbourg, France
| | - Alisa S. Wolberg
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Wolfgang Bergmeier
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Matthew J. Flick
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
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Larsen HJ, Byrne D, Özpolat T, Chauhan A, Bailey SL, Rhoads N, Reed F, Stolla MC, Adili R, Holinstat M, Fu X, Stolla M. Loss of 12-Lipoxygenase Improves the Post-Transfusion Function of Stored Platelets. Arterioscler Thromb Vasc Biol 2023; 43:1990-2007. [PMID: 37650322 PMCID: PMC10538391 DOI: 10.1161/atvbaha.123.319021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 08/14/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND Platelets for transfusion are stored for 5 to 7 days. Previous studies have shown that HETE levels in the storage bag negatively correlate with platelet performance in vivo, suggesting that the dysregulation of bioactive lipid mediators may contribute to the storage lesion. In the current study, we sought to understand how genetic deletion and pharmacological inhibition of 12-LOX (12-lipoxygenase) affects platelets during storage and after transfusion. METHODS Platelets from 12-LOX+/+ (wild-type [WT]) and 12-LOX-/- mice were stored for 24 and 48 hours and profiled using liquid chromatography-tandem mass spectrometry-multiple reaction monitoring or transfused into thrombocytopenic hIL4R (human interleukin 4 receptor)-transgenic mice. Platelet function was assessed by flow cytometry and in vivo thrombosis and hemostasis models. To test the role of the COX-1 (cyclooxygenase-1) pathway, donor mice were treated with acetylsalicylic acid. Human platelets were treated with the 12-LOX inhibitor, VLX-1005, or vehicle, stored, and transfused to NOD/SCID (nonobese diabetic/severe combined immunodeficiency) mice. RESULTS Polyunsaturated fatty acids increased significantly in stored platelets from 12-LOX-/- mice, whereas oxylipin concentrations were significantly higher in WT platelets. After transfusion to thrombocytopenic mice, we observed significantly more baseline αIIbβ3 integrin activation in 12-LOX-/- platelets than in WT platelets. Stored platelets from 12-LOX-/- mice occluded vessels significantly faster than stored WT platelets. In hemostasis models, significantly more stored 12-LOX-/- than WT platelets accumulated at the site of venous injury leading to reduced blood loss. Inhibition of COX-1 abrogated both increased integrin activation and thromboxane generation in stored 12-LOX-/- platelets, highlighting the critical role of this pathway for improved post-transfusion function. Consistent with our mouse studies, human platelets stored with VLX-1005, showed increased integrin activation compared with vehicle-treated platelets after transfusion. CONCLUSIONS Deleting 12-LOX improves the post-transfusion function of stored murine platelets by increasing thromboxane generation through COX-1-dependent arachidonic acid metabolism. Future studies should determine the feasibility and safety of 12-LOX-inhibited platelets transfused to humans.
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Affiliation(s)
| | - Daire Byrne
- Bloodworks Northwest Research Institute, Seattle, WA
| | | | | | | | - Nicole Rhoads
- Bloodworks Northwest Research Institute, Seattle, WA
| | - Franklin Reed
- Bloodworks Northwest Research Institute, Seattle, WA
| | - Massiel C. Stolla
- University of Washington Medical Center, Department of Medicine, Division of Hematology, Seattle, WA
| | - Reheman Adili
- Bloodworks Northwest Research Institute, Seattle, WA
| | | | - Xiaoyun Fu
- Bloodworks Northwest Research Institute, Seattle, WA
- University of Washington Medical Center, Department of Medicine, Division of Hematology, Seattle, WA
| | - Moritz Stolla
- Bloodworks Northwest Research Institute, Seattle, WA
- University of Washington Medical Center, Department of Medicine, Division of Hematology, Seattle, WA
- University of Washington Medical Center, Department of Laboratory Medicine and Pathology, Seattle, WA
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7
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Ballard-Kordeliski A, Lee RH, O'Shaughnessy EC, Kim PY, Jones S, Mackman N, Flick MJ, Paul DS, Adalsteinsson D, Bergmeier W. 4D intravital imaging studies identify platelets as the predominant cellular procoagulant surface in a mouse model of hemostasis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.25.554449. [PMID: 37662350 PMCID: PMC10473702 DOI: 10.1101/2023.08.25.554449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Interplay between platelets, coagulation/fibrinolytic factors, and endothelial cells (ECs) is necessary for effective hemostatic plug formation. This study describes a novel four-dimensional (4D) imaging platform to visualize and quantify hemostatic plug components with high spatiotemporal resolution. Fibrin accumulation following laser-induced endothelial ablation was observed at the EC-platelet plug interface, controlled by the antagonistic balance between fibrin generation and breakdown. Phosphatidylserine (PS) was first detected in close physical proximity to the fibrin ring, followed by exposure across the endothelium. Impaired PS exposure in cyclophilinD -/- mice resulted in a significant reduction in fibrin accumulation. Adoptive transfer and inhibitor studies demonstrated a key role for platelets, but not ECs, in fibrin generation during hemostatic plug formation. Inhibition of fibrinolysis with tranexamic acid (TXA) led to increased fibrin accumulation in WT mice, but not in cyclophilinD -/- mice or WT mice treated with antiplatelet drugs. These studies implicate platelets as the functionally dominant procoagulant surface during hemostatic plug formation. In addition, they suggest that impaired fibrin formation due to reduced platelet procoagulant activity is not reversed by TXA treatment.
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8
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Rudran T, Antoniak S, Flick MJ, Ginsberg MH, Wolberg AS, Bergmeier W, Lee RH. Protease-activated receptors and glycoprotein VI cooperatively drive the platelet component in thromboelastography. J Thromb Haemost 2023; 21:2236-2247. [PMID: 37068592 PMCID: PMC10824270 DOI: 10.1016/j.jtha.2023.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/27/2023] [Accepted: 04/09/2023] [Indexed: 04/19/2023]
Abstract
BACKGROUND Thromboelastography (TEG) is used for real-time determination of hemostatic status in patients with acute risk of bleeding. Thrombin is thought to drive clotting in TEG through generation of polymerized fibrin and activation of platelets through protease-activated receptors (PARs). However, the specific role of platelet agonist receptors and signaling in TEG has not been reported. OBJECTIVES Here, we investigated the specific receptors and signaling pathways required for platelet function in TEG using genetic and pharmacologic inhibition of platelet proteins in mouse and human blood samples. METHODS Clotting parameters (R time, α-angle [α], and maximum amplitude [MA]), were determined in recalcified, kaolin-triggered citrated blood samples using a TEG 5000 analyzer. RESULTS We confirmed the requirement of platelets, platelet contraction, and αIIbβ3 integrin function for normal α and MA. Loss of the integrin adaptor Talin1 in megakaryocytes/platelets (Talin1mKO) also reduced α and MA, but only minimal defects were observed in samples from mice lacking Rap1 GTPase signaling. PAR4mKO samples showed impaired α but normal MA. However, impaired TEG traces similar to those in platelet-depleted samples were observed with samples from PAR4mKO mice depleted of glycoprotein VI on platelets or with addition of a Syk inhibitor. We reproduced these results in human blood with combined inhibition of PAR1, PAR4, and Syk. CONCLUSION Our results demonstrate that standard TEG is not sensitive to platelet signaling pathways critical for integrin inside-out activation and platelet hemostatic function. Furthermore, we provide the first evidence that PARs and glycoprotein VI play redundant roles in platelet-mediated clot contraction in TEG.
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Affiliation(s)
- Tanvi Rudran
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Silvio Antoniak
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Matthew J Flick
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Mark H Ginsberg
- Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Alisa S Wolberg
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Wolfgang Bergmeier
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Robert H Lee
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
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9
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Paul DS, Blatt TN, Schug WJ, Clark EG, Kawano T, Mackman N, Murcia S, Poe KO, Mwiza JMN, Harden TK, Bergmeier W, Nicholas RA. Loss of P2Y 1 receptor desensitization does not impact hemostasis or thrombosis despite increased platelet reactivity in vitro. J Thromb Haemost 2023; 21:1891-1902. [PMID: 36958516 PMCID: PMC10809801 DOI: 10.1016/j.jtha.2023.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/20/2023] [Accepted: 03/09/2023] [Indexed: 03/25/2023]
Abstract
BACKGROUND The hemostatic plug formation at sites of vascular injury is strongly dependent on rapid platelet activation and integrin-mediated adhesion and aggregation. However, to prevent thrombotic complications, platelet aggregate formation must be a self-limiting process. The second-wave mediator adenosine diphosphate (ADP) activates platelets via Gq-coupled P2Y1 and Gi-coupled P2Y12 receptors. After ADP exposure, the P2Y1 receptor undergoes rapid phosphorylation-induced desensitization, a negative feedback mechanism believed to be critical for limiting thrombus growth. OBJECTIVE The objective of this study was to examine the role of rapid P2Y1 receptor desensitization on platelet function and thrombus formation in vivo. METHODS We analyzed a novel knock-in mouse strain expressing a P2Y1 receptor variant that cannot be phosphorylated beyond residue 340 (P2Y1340-0P), thereby preventing the desensitization of the receptor. RESULTS P2Y1340-0P mice followed a Mendelian inheritance pattern, and peripheral platelet counts were comparable between P2Y1340-0P/340-0P and control mice. In vitro, P2Y1340-0P/340-0P platelets were hyperreactive to ADP, showed a robust activation response to the P2Y1 receptor-selective agonist, MRS2365, and did not desensitize in response to repeated ADP challenge. We observed increased calcium mobilization, protein kinase C substrate phosphorylation, alpha granule release, activation of the small GTPase Rap1, and integrin inside-out activation/aggregation. This hyperreactivity, however, did not lead to increased platelet adhesion or excessive plug formation under physiological shear conditions. CONCLUSION Our studies demonstrate that receptor phosphorylation at the C-terminus is critical for P2Y1 receptor desensitization in platelets and that impaired desensitization leads to increased P2Y1 receptor signaling in vitro. Surprisingly, desensitization of the P2Y1 receptor is not required for limiting platelet adhesion/aggregation at sites of vascular injury, likely because ADP is degraded quickly or washed away in the bloodstream.
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Affiliation(s)
- David S Paul
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. https://twitter.com/David_S_Paul
| | - Tasha N Blatt
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Wyatt J Schug
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Emily G Clark
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tomohiro Kawano
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nigel Mackman
- UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sebastian Murcia
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kathryn O Poe
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jean Marie N Mwiza
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - T Kendall Harden
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Wolfgang Bergmeier
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; UNC Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Robert A Nicholas
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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10
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Demers M, Aleman MM, Kistanova E, Peters R, Salas J, Seth Chhabra E. Efanesoctocog alfa elicits functional clot formation that is indistinguishable to that of recombinant factor VIII. J Thromb Haemost 2022; 20:1674-1683. [PMID: 35466511 PMCID: PMC9320793 DOI: 10.1111/jth.15741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 12/01/2022]
Abstract
BACKGROUND Factor VIII (FVIII) binding to endogenous von Willebrand factor (VWF) has constrained half-life extension of recombinant FVIII (rFVIII) products for hemophilia A. Efanesoctocog alfa (rFVIIIFc-VWF-XTEN; BIVV001) is a novel fusion protein designed to decouple FVIII from VWF in circulation and maximize half-life prolongation by XTEN® polypeptides and Fc fusion. FVIII, VWF, and platelets interact to achieve normal hemostasis. Thus, bioengineered FVIII replacement products, such as efanesoctocog alfa, require comprehensive assessment of their hemostatic potential. OBJECTIVES We compared functional clot formation and injury-induced platelet accumulation between efanesoctocog alfa and rFVIII. PATIENTS/METHODS The hemostatic potential of efanesoctocog alfa and rFVIII were assessed by measuring their dose-dependent effects on in vitro fibrin generation in hemophilic plasma and in vivo injury-induced platelet accumulation using intravital microscopy and repeat saphenous vein laser-induced injuries in hemophilia A mice. RESULTS Equal concentrations of efanesoctocog alfa or rFVIII (up to 1 IU/ml) added to plasma from patients with hemophilia A elicited similar kinetics for dose-dependent fibrin polymerization between factor products. In the presence of tissue plasminogen activator (tPA), clots formed had similar stability between products. Single intravenous doses (50, 100, or 150 IU/kg) of efanesoctocog alfa or rFVIII shortly before repeat saphenous vein laser-induced injuries increased platelet accumulation over time in a dose-dependent manner in hemophilia A mice. Platelet deposition kinetics were similar between products. CONCLUSIONS Equivalent doses of efanesoctocog alfa and rFVIII had similar efficacy in promoting fibrin clot formation and injury-induced platelet accumulation. The hemostatic potential of efanesoctocog alfa was indistinguishable from that of rFVIII.
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11
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Traumatic vessel injuries initiating hemostasis generate high shear conditions. Blood Adv 2022; 6:4834-4846. [PMID: 35728058 PMCID: PMC9631664 DOI: 10.1182/bloodadvances.2022007550] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 06/10/2022] [Indexed: 12/02/2022] Open
Abstract
Various types of lesions in small and large mouse and human vessels result in high shear rates and elongational flows. The relative hydrodynamic resistance of the vessel and wound explains a decrease in shear rate with increase in injury size.
Blood flow is a major regulator of hemostasis and arterial thrombosis. The current view is that low and intermediate flows occur in intact healthy vessels, whereas high shear levels (>2000 s−1) are reached in stenosed arteries, notably during thrombosis. To date, the shear rates occurring at the edge of a lesion in an otherwise healthy vessel are nevertheless unknown. The aim of this work was to measure the shear rates prevailing in wounds in a context relevant to hemostasis. Three models of vessel puncture and transection were developed and characterized for a study that was implemented in mice and humans. Doppler probe measurements supplemented by a computational model revealed that shear rates at the edge of a wound reached high values, with medians of 22 000 s−1, 25 000 s−1, and 7000 s−1 after puncture of the murine carotid artery, aorta, or saphenous vein, respectively. Similar shear levels were observed after transection of the mouse spermatic artery. These results were confirmed in a human venous puncture model, where shear rates in a catheter implanted in the cubital vein reached 2000 to 27 000 s−1. In all models, the high shear conditions were accompanied by elevated levels of elongational flow exceeding 1000 s−1. In the puncture model, the shear rates decreased steeply with increasing injury size. This phenomenon could be explained by the low hydrodynamic resistance of the injuries as compared with that of the downstream vessel network. These findings show that high shear rates (>3000 s−1) are relevant to hemostasis and not exclusive to arterial thrombosis.
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12
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Chen W, Wilson MS, Wang Y, Bergmeier W, Lanza F, Li R. Fast clearance of platelets in a commonly used mouse model for GPIbα is impeded by an anti-GPIbβ antibody derivative. J Thromb Haemost 2022; 20:1451-1463. [PMID: 35305057 PMCID: PMC9133214 DOI: 10.1111/jth.15702] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 02/21/2022] [Accepted: 03/14/2022] [Indexed: 01/26/2023]
Abstract
BACKGROUND Glycoprotein (GP)Ibα plays a critical role in regulating platelet clearance. Recently, we identified the mechanosensory domain (MSD) in GPIbα and reported evidence to suggest that unfolding of the GPIbα MSD induces exposure of the Trigger sequence therein and subsequent GPIb-IX signaling that accelerates platelet clearance. In a commonly used transgenic mouse model, IL4R-IbαTg, where the Trigger sequence is constitutively exposed, constitutive GPIb-IX-mediated cellular signals are present. Clearance of their platelets is also significantly faster than that of wild-type mice. Previously, an anti-GPIbβ antibody RAM.1 was developed. RAM.1 inhibits GPIbα-dependent platelet signaling and activation. Further, RAM.1 also inhibits anti-GPIbα antibody-mediated filopodia formation. OBJECTIVE To investigate whether RAM.1 can ameliorate trigger sequence exposure-mediated platelet clearance. METHODS Spontaneous filopodia were measured by confocal microscopy. Other platelet signaling events were measured by flow cytometry. Endogenous platelet life span was tracked by Alexa 488-labeled anti-mouse GPIX antibody. RESULT Transfected Chinese hamster ovary cells stably expressing the same chimeric IL4R-Ibα protein complex as in IL4R-IbαTg mice also constitutively exhibit filopodia, and that such filopodia could be abolished by treatment of RAM.1. Further, transfusion of a recombinant RAM.1 derivative that is devoid of its Fc portion significantly extends the endogenous life span of IL4R-IbαTg platelets. CONCLUSION These results provide the key evidence supporting the causative link of Trigger sequence exposure to accelerated platelet clearance, and suggest that a RAM.1 derivative may be therapeutically developed to treat GPIb-IX-mediated thrombocytopenia.
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Affiliation(s)
- Wenchun Chen
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Departments of Pediatrics, Emory University School of Medicine Atlanta, GA
| | - Moriah S. Wilson
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Departments of Pediatrics, Emory University School of Medicine Atlanta, GA
| | - Yingchun Wang
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Departments of Pediatrics, Emory University School of Medicine Atlanta, GA
| | - Wolfgang Bergmeier
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Francois Lanza
- Université de Strasbourg, INSERM, BPPS UMR-S1255, Strasbourg, France
| | - Renhao Li
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Departments of Pediatrics, Emory University School of Medicine Atlanta, GA
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13
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Both G protein-coupled and immunoreceptor tyrosine-based activation motif receptors mediate venous thrombosis in mice. Blood 2022; 139:3194-3203. [PMID: 35358299 PMCID: PMC9136879 DOI: 10.1182/blood.2022015787] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 03/27/2022] [Indexed: 01/26/2023] Open
Abstract
Platelets are critical in hemostasis and a major contributor to arterial thrombosis (AT). (Pre)clinical studies suggest platelets also contribute to venous thrombosis (VT), but the mechanisms are largely unknown. We hypothesized that in VT, platelets use signaling machinery distinct from AT. Here we aimed to characterize the contributions of platelet G protein-coupled (GPCR) and immunoreceptor tyrosine-based activation motif (ITAM) receptor signaling to VT. Wild-type (WT) and transgenic mice were treated with inhibitors to selectively inhibit platelet-signaling pathways: ITAM-CLEC2 (Clec2mKO), glycoprotein VI (JAQ1 antibody), and Bruton's tyrosine kinase (ibrutinib); GPCR-cyclooxygenase 1 (aspirin); and P2Y12 (clopidogrel). VT was induced by inferior vena cava stenosis. Thrombin generation in platelet-rich plasma and whole-blood clot formation were studied ex vivo. Intravital microscopy was used to study platelet-leukocyte interactions after flow restriction. Thrombus weights were reduced in WT mice treated with high-dose aspirin + clopidogrel (dual antiplatelet therapy [DAPT]) but not in mice treated with either inhibitor alone or low-dose DAPT. Similarly, thrombus weights were reduced in mice with impaired ITAM signaling (Clec2mKO + JAQ1; WT + ibrutinib) but not in Clec2mKO or WT + JAQ1 mice. Both aspirin and clopidogrel, but not ibrutinib, protected mice from FeCl3-induced AT. Thrombin generation and clot formation were normal in blood from high-dose DAPT- or ibrutinib-treated mice; however, platelet adhesion and platelet-neutrophil aggregate formation at the vein wall were reduced in mice treated with high-dose DAPT or ibrutinib. In summary, VT initiation requires platelet activation via GPCRs and ITAM receptors. Strong inhibition of either signaling pathway reduces VT in mice.
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14
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Scanning laser-induced endothelial injury: a standardized and reproducible thrombosis model for intravital microscopy. Sci Rep 2022; 12:3955. [PMID: 35273275 PMCID: PMC8913794 DOI: 10.1038/s41598-022-07892-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 02/21/2022] [Indexed: 11/08/2022] Open
Abstract
Vascular injury models are indispensable for studying thrombotic processes in vivo. Amongst the available methods for inducing thrombosis, laser-induced endothelial injury (LIEI) has several unique advantages. However, a lack of methodological standardization and expensive instrumentation remain significant problems decreasing reproducibility and impeding the adoption of LIEI in the wider scientific community. In this, study, we developed a standardized protocol for scanning laser-induced endothelial injury (scanning-LIEI) of murine mesenteric veins using the intrinsic 405 nm laser of a conventional laser scanning confocal microscope. We show that our model produces thrombi with prominent core-shell architectures and minimal radiation-related fluorescence artefacts. In comparison with previous methods, the scanning-LIEI model exhibits reduced experimental variability, enabling the demonstration of dose-response effects for anti-thrombotic drugs using small animal cohorts. Scanning-LIEI using the intrinsic 405 nm laser of a confocal laser scanning microscope represents a new method to induce standardized vascular injury with improved reproducibility of thrombus formation. The reduced need for instrument customisation and user experience means that this model could be more readily adopted in the research community.
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15
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Hypofibrinogenemia with preserved hemostasis and protection from thrombosis in mice with an Fga truncation mutation. Blood 2022; 139:1374-1388. [PMID: 34905618 PMCID: PMC8900273 DOI: 10.1182/blood.2021012537] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 11/29/2021] [Indexed: 11/20/2022] Open
Abstract
Genetic variants within the fibrinogen Aα chain encoding the αC-region commonly result in hypodysfibrinogenemia in patients. However, the (patho)physiological consequences and underlying mechanisms of such mutations remain undefined. Here, we generated Fga270 mice carrying a premature termination codon within the Fga gene at residue 271. The Fga270 mutation was compatible with Mendelian inheritance for offspring of heterozygous crosses. Adult Fga270/270 mice were hypofibrinogenemic with ∼10% plasma fibrinogen levels relative to FgaWT/WT mice, linked to 90% reduction in hepatic Fga messenger RNA (mRNA) because of nonsense-mediated decay of the mutant mRNA. Fga270/270 mice had preserved hemostatic potential in vitro and in vivo in models of tail bleeding and laser-induced saphenous vein injury, whereas Fga-/- mice had continuous bleeding. Platelets from FgaWT/WT and Fga270/270 mice displayed comparable initial aggregation following adenosine 5'-diphosphate stimulation, but Fga270/270 platelets quickly disaggregated. Despite ∼10% plasma fibrinogen, the fibrinogen level in Fga270/270 platelets was ∼30% of FgaWT/WT platelets with a compensatory increase in fibronectin. Notably, Fga270/270 mice showed complete protection from thrombosis in the inferior vena cava stasis model. In a model of Staphylococcus aureus peritonitis, Fga270/270 mice supported local, fibrinogen-mediated bacterial clearance and host survival comparable to FgaWT/WT, unlike Fga-/- mice. Decreasing the normal fibrinogen levels to ∼10% with small interfering RNA in mice also provided significant protection from venous thrombosis without compromising hemostatic potential and antimicrobial function. These findings both reveal novel molecular mechanisms underpinning fibrinogen αC-region truncation mutations and highlight the concept that selective fibrinogen reduction may be efficacious for limiting thrombosis while preserving hemostatic and immune protective functions.
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16
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Lee RH, Kawano T, Grover SP, Bharathi V, Martinez D, Cowley DO, Mackman N, Bergmeier W, Antoniak S. Genetic deletion of platelet PAR4 results in reduced thrombosis and impaired hemostatic plug stability. J Thromb Haemost 2022; 20:422-433. [PMID: 34689407 PMCID: PMC8792346 DOI: 10.1111/jth.15569] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Protease-activated receptor 4 (PAR4) is expressed by a wide variety of cells, including megakaryocytes/platelets, immune cells, cardiomyocytes, and lung epithelial cells. It is the only functional thrombin receptor on murine platelets. A global deficiency of PAR4 is associated with impaired hemostasis and reduced thrombosis. OBJECTIVE We aimed to generate a mouse line with a megakaryocyte/platelet-specific deletion of PAR4 (PAR4fl/fl ;PF4Cre+ ) and use the mouse line to investigate the role of platelet PAR4 in hemostasis and thrombosis in mice. METHODS Platelets from PAR4fl/fl ;PF4Cre+ were characterized in vitro. Arterial and venous thrombosis was analyzed. Hemostatic plug formation was analyzed using a saphenous vein laser injury model in mice with global or megakaryocyte/platelet-specific deletion of PAR4 or wild-type mice treated with thrombin or glycoprotein VI (GPVI) inhibitors. RESULTS PAR4fl/fl ;PF4Cre+ platelets were unresponsive to thrombin or specific PAR4 stimulation but not to other agonists. PAR4-/- and PAR4fl/fl ;PF4Cre+ mice both exhibited a similar reduction in arterial thrombosis compared to their respective controls. More importantly, we show for the first time that platelet PAR4 is critical for venous thrombosis in mice. In addition, PAR4-/- mice and PAR4fl/fl ;PF4Cre+ mice exhibited a similar impairment in hemostatic plug stability in a saphenous vein laser injury model. Inhibition of thrombin in wild-type mice gave a similar phenotype. Combined PAR4 deficiency on platelets with GPVI inhibition did not impair hemostatic plug formation but further reduced plug stability. CONCLUSION We generated a novel PAR4fl/fl ;PF4Cre+ mouse line. We used this mouse line to show that PAR4 signaling in platelets is critical for arterial and venous thrombosis and hemostatic plug stability.
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Affiliation(s)
- Robert H. Lee
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Tomohiro Kawano
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Steven P. Grover
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Vanthana Bharathi
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - David Martinez
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Dale O. Cowley
- UNC Animal Models Core, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nigel Mackman
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Hematology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Wolfgang Bergmeier
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Silvio Antoniak
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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17
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Venous puncture wound hemostasis results in a vaulted thrombus structured by locally nucleated platelet aggregates. Commun Biol 2021; 4:1090. [PMID: 34531522 PMCID: PMC8445961 DOI: 10.1038/s42003-021-02615-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 08/03/2021] [Indexed: 12/22/2022] Open
Abstract
Primary hemostasis results in a platelet-rich thrombus that has long been assumed to form a solid plug. Unexpectedly, our 3-dimensional (3D) electron microscopy of mouse jugular vein puncture wounds revealed that the resulting thrombi were structured about localized, nucleated platelet aggregates, pedestals and columns, that produced a vaulted thrombus capped by extravascular platelet adherence. Pedestal and column surfaces were lined by procoagulant platelets. Furthermore, early steps in thrombus assembly were sensitive to P2Y12 inhibition and late steps to thrombin inhibition. Based on these results, we propose a Cap and Build, puncture wound paradigm that should have translational implications for bleeding control and hemostasis. Rhee, Pokrovskaya et al. utilize 3D electron microscopy of mouse jugular vein puncture wounds to reveal thrombi structured around localized, nucleated platelet aggregates that produced a vaulted thrombus capped by extravascular platelet adherence. As a result, the authors propose a “Cap and Build” paradigm of primary hemostasis.
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18
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Platelet transfusion for patients with platelet dysfunction: effectiveness, mechanisms, and unanswered questions. Curr Opin Hematol 2021; 27:378-385. [PMID: 32868672 DOI: 10.1097/moh.0000000000000608] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW In this review, we discuss current clinical guidelines and potential underlying mechanisms regarding platelet transfusion therapy in patients at risk of bleeding, comparing management of patients with thrombocytopenia versus those with qualitative platelet disorders. RECENT FINDINGS Platelet transfusion therapy is highly effective in managing bleeding in patients with hypoproliferative thrombocytopenia. Clinical trials have demonstrated that platelet transfusion can be used at a lower trigger threshold and reduced platelet doses, and may be used therapeutically rather than prophylactically in some situations, although additional data are needed. In patients with inherited platelet disorders such as Glanzmann's Thrombasthenia or those with RASGRP2 mutations, platelet transfusion may be ineffective because of competition between transfused and endogenous platelets at the site of vascular injury. Successful management of these patients may require transfusion of additional platelet units, or mechanism-driven combination therapy with other pro-hemostatic agents. In patients on antiplatelet therapy, timing of transfusion and inhibitor mechanism-of-action are key in determining therapeutic success. SUMMARY Expanding our understanding of the mechanisms by which transfused platelets exert their pro-hemostatic function in various bleeding disorders will improve the appropriate use of platelet transfusion.
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19
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Adili R, Jackson M, Stanger L, Dai X, Li M, Li BX, Holinstat M. Slounase, a Batroxobin Containing Activated Factor X Effectively Enhances Hemostatic Clot Formation and Reducing Bleeding in Hypocoagulant Conditions in Mice. Clin Appl Thromb Hemost 2021; 27:10760296211018510. [PMID: 34047195 PMCID: PMC8165871 DOI: 10.1177/10760296211018510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Uncontrolled bleeding associated with trauma and surgery is the leading
cause of preventable death. Batroxobin, a snake venom-derived
thrombin-like serine protease, has been shown to clot fibrinogen by
cleaving fibrinopeptide A in a manner distinctly different from
thrombin, even in the presence of heparin. The biochemical properties
of batroxobin and its effect on coagulation have been well
characterized in vitro. However, the efficacy of
batroxobin on hemostatic clot formation in vivo is
not well studied due to the lack of reliable in vivo
hemostasis models. Here, we studied the efficacy of batroxobin and
slounase, a batroxobin containing activated factor X, on hemostatic
clot composition and bleeding using intravital microcopy laser
ablation hemostasis models in micro and macro vessels and liver
puncture hemostasis models in normal and heparin-induced hypocoagulant
mice. We found that prophylactic treatment in wild-type mice with
batroxobin, slounase and activated factor X significantly enhanced
platelet-rich fibrin clot formation following vascular injury. In
heparin-treated mice, batroxobin treatment resulted in detectable
fibrin formation and a modest increase in hemostatic clot size, while
activated factor X had no effect. In contrast, slounase treatment
significantly enhanced both platelet recruitment and fibrin formation,
forming a stable clot and shortening bleeding time and blood loss in
wild-type and heparin-treated hypocoagulant mice. Our data demonstrate
that, while batroxobin enhances fibrin formation, slounase was able to
enhance hemostasis in normal mice and restore hemostasis in
hypocoagulant conditions via the enhancement of fibrin formation and
platelet activation, indicating that slounase is more effective in
controlling hemorrhage.
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Affiliation(s)
- Reheman Adili
- Department of Pharmacology, 1259University of Michigan, Ann Arbor, MI, USA
| | - Madeline Jackson
- Department of Pharmacology, 1259University of Michigan, Ann Arbor, MI, USA
| | - Livia Stanger
- Department of Pharmacology, 1259University of Michigan, Ann Arbor, MI, USA
| | - Xiangrong Dai
- Zhaoke Pharmaceutical (Hefei) Co. Limited, Hefei, Anhui, China
| | - Mandy Li
- Lee's Pharmaceutical Holdings Limited. Shatin, Hong Kong, China
| | | | - Michael Holinstat
- Department of Pharmacology, 1259University of Michigan, Ann Arbor, MI, USA.,Department of Internal Medicine, Division of Cardiovascular Medicine, 1259University of Michigan, Ann Arbor, MI, USA
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20
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Poventud-Fuentes I, Kwon KW, Seo J, Tomaiuolo M, Stalker TJ, Brass LF, Huh D. A Human Vascular Injury-on-a-Chip Model of Hemostasis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2004889. [PMID: 33150735 PMCID: PMC8049960 DOI: 10.1002/smll.202004889] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/28/2020] [Indexed: 05/02/2023]
Abstract
Hemostasis is an innate protective mechanism that plays a central role in maintaining the homeostasis of the vascular system during vascular injury. Studying this essential physiological process is often challenged by the difficulty of modeling and probing the complex dynamics of hemostatic responses in the native context of human blood vessels. To address this major challenge, this paper describes a microengineering approach for in vitro modeling of hemostasis. This microphysiological model replicates the living endothelium, multilayered microarchitecture, and procoagulant activity of human blood vessels, and is also equipped with a microneedle that is actuated with spatial precision to simulate penetrating vascular injuries. The system recapitulates key features of the hemostatic response to acute vascular injury as observed in vivo, including i) thrombin-driven accumulation of platelets and fibrin, ii) formation of a platelet- and fibrin-rich hemostatic plug that halts blood loss, and iii) matrix deformation driven by platelet contraction for wound closure. Moreover, the potential use of this model for drug testing applications is demonstrated by evaluating the effects of anticoagulants and antiplatelet agents that are in current clinical use. The vascular injury-on-a-chip may serve as an enabling platform for preclinical investigation of hematological disorders and emerging therapeutic approaches against them.
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Affiliation(s)
| | - Keon Woo Kwon
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Jeongyun Seo
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Maurizio Tomaiuolo
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Timothy J Stalker
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Lawrence F Brass
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Dongeun Huh
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Institute of Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- NSF Science and Technology Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
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21
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Grover SP, Mackman N. Description of the first mutation in the human tissue factor gene associated with a bleeding tendency. J Thromb Haemost 2021; 19:3-6. [PMID: 33225609 DOI: 10.1111/jth.15151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 10/19/2020] [Accepted: 10/19/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Steven P Grover
- UNC Blood Research Center, Division of Hematology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nigel Mackman
- UNC Blood Research Center, Division of Hematology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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22
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Lei X, MacKeigan DT, Ni H. Control of data variations in intravital microscopy thrombosis models. J Thromb Haemost 2020; 18:2823-2825. [PMID: 33463084 DOI: 10.1111/jth.15062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Xi Lei
- Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Toronto Platelet Immunobiology Group, Toronto, ON, Canada
| | - Daniel Thomas MacKeigan
- Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Toronto Platelet Immunobiology Group, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Heyu Ni
- Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Toronto Platelet Immunobiology Group, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Canadian Blood Services Centre for Innovation, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
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23
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Lagarrigue F, Paul DS, Gingras AR, Valadez AJ, Sun H, Lin J, Cuevas MN, Ablack JN, Lopez-Ramirez MA, Bergmeier W, Ginsberg MH. Talin-1 is the principal platelet Rap1 effector of integrin activation. Blood 2020; 136:1180-1190. [PMID: 32518959 PMCID: PMC7472713 DOI: 10.1182/blood.2020005348] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/29/2020] [Indexed: 12/14/2022] Open
Abstract
Ras-related protein 1 (Rap1) is a major convergence point of the platelet-signaling pathways that result in talin-1 binding to the integrin β cytoplasmic domain and consequent integrin activation, platelet aggregation, and effective hemostasis. The nature of the connection between Rap1 and talin-1 in integrin activation is an important remaining gap in our understanding of this process. Previous work identified a low-affinity Rap1-binding site in the talin-1 F0 domain that makes a small contribution to integrin activation in platelets. We recently identified an additional Rap1-binding site in the talin-1 F1 domain that makes a greater contribution than F0 in model systems. Here we generated mice bearing point mutations, which block Rap1 binding without affecting talin-1 expression, in either the talin-1 F1 domain (R118E) alone, which were viable, or in both the F0 and F1 domains (R35E,R118E), which were embryonic lethal. Loss of the Rap1-talin-1 F1 interaction in platelets markedly decreases talin-1-mediated activation of platelet β1- and β3-integrins. Integrin activation and platelet aggregation in mice whose platelets express only talin-1(R35E, R118E) are even more impaired, resembling the defect seen in platelets lacking both Rap1a and Rap1b. Although Rap1 is important in thrombopoiesis, platelet secretion, and surface exposure of phosphatidylserine, loss of the Rap1-talin-1 interaction in talin-1(R35E, R118E) platelets had little effect on these processes. These findings show that talin-1 is the principal direct effector of Rap1 GTPases that regulates platelet integrin activation in hemostasis.
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Affiliation(s)
- Frederic Lagarrigue
- Department of Medicine, University of California, San Diego, La Jolla, CA
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Centre National de la Recherche Scientifique (CNRS), Université Paul Sabatier (UPS), Université de Toulouse, Toulouse, France
| | - David S Paul
- UNC Blood Research Center and
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | | | - Andrew J Valadez
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Hao Sun
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Jenny Lin
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Monica N Cuevas
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Jailal N Ablack
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Miguel Alejandro Lopez-Ramirez
- Department of Medicine, University of California, San Diego, La Jolla, CA
- Department of Pharmacology, University of California, San Diego, La Jolla, CA
| | - Wolfgang Bergmeier
- UNC Blood Research Center and
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Mark H Ginsberg
- Department of Medicine, University of California, San Diego, La Jolla, CA
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24
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Klein MK, Kassam HA, Lee RH, Bergmeier W, Peters EB, Gillis DC, Dandurand BR, Rouan JR, Karver MR, Struble MD, Clemons TD, Palmer LC, Gavitt B, Pritts TA, Tsihlis ND, Stupp SI, Kibbe MR. Development of Optimized Tissue-Factor-Targeted Peptide Amphiphile Nanofibers to Slow Noncompressible Torso Hemorrhage. ACS NANO 2020; 14:6649-6662. [PMID: 32469498 PMCID: PMC7587470 DOI: 10.1021/acsnano.9b09243] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Noncompressible torso hemorrhage accounts for a significant portion of preventable trauma deaths. We report here on the development of injectable, targeted supramolecular nanotherapeutics based on peptide amphiphile (PA) molecules that are designed to target tissue factor (TF) and, therefore, selectively localize to sites of injury to slow hemorrhage. Eight TF-targeting sequences were identified, synthesized into PA molecules, coassembled with nontargeted backbone PA at various weight percentages, and characterized via circular dichroism spectroscopy, transmission electron microscopy, and X-ray scattering. Following intravenous injection in a rat liver hemorrhage model, two of these PA nanofiber coassemblies exhibited the most specific localization to the site of injury compared to controls (p < 0.05), as quantified using immunofluorescence imaging of injured liver and uninjured organs. To determine if the nanofibers were targeting TF in vivo, a mouse saphenous vein laser injury model was performed and showed that TF-targeted nanofibers colocalized with fibrin, demonstrating increased levels of nanofiber at TF-rich sites. Thromboelastograms obtained using samples of heparinized rat whole blood containing TF demonstrated that no clots were formed in the absence of TF-targeted nanofibers. Lastly, both PA nanofiber coassemblies decreased blood loss in comparison to sham and backbone nanofiber controls by 35-59% (p < 0.05). These data demonstrate an optimal TF-targeted nanofiber that localizes selectively to sites of injury and TF exposure, and, interestingly, reduces blood loss. This research represents a promising initial phase in the development of a TF-targeted injectable therapeutic to reduce preventable deaths from hemorrhage.
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Affiliation(s)
- Mia K. Klein
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Hussein Aziz Kassam
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Robert H. Lee
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, 27599, USA
- UNC Blood Research Center, University of North Carolina, Chapel Hill, NC, 27514, USA
| | - Wolfgang Bergmeier
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, 27599, USA
- UNC Blood Research Center, University of North Carolina, Chapel Hill, NC, 27514, USA
| | - Erica B. Peters
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - David C. Gillis
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Brooke R. Dandurand
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Jessica R. Rouan
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Mark R. Karver
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA
| | - Mark D. Struble
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA
| | - Tristan D. Clemons
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA
- Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA
- School of Molecular Sciences, University of Western Australia, Perth, WA, 6009, Australia
| | - Liam C. Palmer
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA
- Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA
| | - Brian Gavitt
- United States Air Force School of Aerospace Medicine, Wright-Patterson AFB, OH, 45433, USA
| | - Timothy A. Pritts
- Department of Surgery, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Nick D. Tsihlis
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Samuel I. Stupp
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA
- Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
- Department of Medicine, Northwestern University, Chicago, IL, 60611, USA
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Melina R. Kibbe
- Department of Surgery and Center for Nanotechnology in Drug Delivery, University of North Carolina, Chapel Hill, NC, 27599, USA
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, 27599, USA
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25
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Paul DS, Bergmeier W. Novel Mouse Model for Studying Hemostatic Function of Human Platelets. Arterioscler Thromb Vasc Biol 2020; 40:1891-1904. [PMID: 32493172 DOI: 10.1161/atvbaha.120.314304] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Platelets are critical to the formation of a hemostatic plug and the pathogenesis of atherothrombosis. Preclinical animal models, especially the mouse, provide an important platform to assess the efficacy and safety of antiplatelet drugs. However, these studies are limited by inherent differences between human and mouse platelets and the species-selectivity of many drugs. To circumvent these limitations, we developed a new protocol for the adoptive transfer of human platelets into thrombocytopenic nonobese diabetic/severe combined immune deficiency mice, that is, a model where all endogenous platelets are replaced by human platelets in mice accepting xenogeneic tissues. Approach and Results: To demonstrate the power of this new model, we visualized and quantified hemostatic plug formation and stability by intravital spinning disk confocal microscopy following laser ablation injury to the saphenous vein. Integrin αIIbβ3-dependent hemostatic platelet plug formation was achieved within ≈30 seconds after laser ablation injury in humanized platelet mice. Pretreatment of mice with standard dual antiplatelet therapy (Aspirin+Ticagrelor) or PAR1 inhibitor, L-003959712 (an analog of vorapaxar), mildly prolonged the bleeding time and significantly reduced platelet adhesion to the site of injury. Consistent with findings from clinical trials, inhibition of PAR1 in combination with dual antiplatelet therapy markedly prolonged bleeding time in humanized platelet mice. CONCLUSIONS We propose that this novel mouse model will provide a robust platform to test and predict the safety and efficacy of experimental antiplatelet drugs and to characterize the hemostatic function of synthetic, stored and patient platelets.
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Affiliation(s)
- David S Paul
- From the Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill (D.S.P., W.B.).,UNC Blood Research Center, University of North Carolina, Chapel Hill (D.S.P., W.B.)
| | - Wolfgang Bergmeier
- From the Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill (D.S.P., W.B.).,UNC Blood Research Center, University of North Carolina, Chapel Hill (D.S.P., W.B.)
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26
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Abstract
A confluence of technological advances in genetic manipulation and molecular-based fluorescence imaging has led to the widespread adoption of laser injury models to study hemostasis and thrombosis in mice. In all animal models of hemostasis and thrombosis, detailing the nature of experimentally induced vascular injury is paramount in enabling appropriate interpretation of experimental results. A careful appraisal of the literature shows that direct laser-induced injury can result in variable degrees of vascular damage. This review will compare and contrast models of laser injury utilized in the field, with an emphasis on the mechanism and extent of injury, the use of laser injury in different vascular beds and the molecular mechanisms regulating the response to injury. All of these topics will be discussed in the context of how distinct applications of laser injury models may be viewed as representing thrombosis and/or hemostasis.
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Affiliation(s)
- Timothy J Stalker
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA, USA
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27
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Abstract
Hemostasis is the normal process that produces a blood clot at a site of vascular injury. Mice are widely used to study hemostasis and abnormalities of blood coagulation because their hemostatic system is similar in most respects to that of humans, and their genomes can be easily manipulated to create models of inherited human coagulation disorders. Two of the most widely used techniques for assessing hemostasis in mice are the tail bleeding time (TBT) and saphenous vein bleeding (SVB) models. Here we discuss the use of these methods in the evaluation of hemostasis, and the advantages and limits of using mice as surrogates for studying hemostasis in humans.
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Affiliation(s)
- Bassem M Mohammed
- Department of Pathology, Microbiology and Immunology, Vanderbilt University , Nashville, TN, USA.,Department of Pathology and Immunology, Washington University , St. Louis, MO, USA
| | - Dougald M Monroe
- UNC Blood Research Center and Hematology/Oncology, University of North Carolina , Chapel Hill, NC, USA
| | - David Gailani
- Department of Pathology, Microbiology and Immunology, Vanderbilt University , Nashville, TN, USA
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28
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Lee RH, Piatt R, Dhenge A, Lozano ML, Palma-Barqueros V, Rivera J, Bergmeier W. Impaired hemostatic activity of healthy transfused platelets in inherited and acquired platelet disorders: Mechanisms and implications. Sci Transl Med 2019; 11:eaay0203. [PMID: 31826978 PMCID: PMC10824274 DOI: 10.1126/scitranslmed.aay0203] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/11/2019] [Indexed: 12/21/2022]
Abstract
Platelet transfusions can fail to prevent bleeding in patients with inherited platelet function disorders (IPDs), such as Glanzmann's thrombasthenia (GT; integrin αIIbβ3 dysfunction), Bernard-Soulier syndrome [BSS; glycoprotein (GP) Ib/V/IX dysfunction], and the more recently identified nonsyndromic RASGRP2 variants. Here, we used IPD mouse models and real-time imaging of hemostatic plug formation to investigate whether dysfunctional platelets impair the hemostatic function of healthy donor [wild-type (WT)] platelets. In Rasgrp2-/- mice or mice with platelet-specific deficiency in the integrin adaptor protein TALIN1 ("GT-like"), WT platelet transfusion was ineffective unless the ratio between mutant and WT platelets was ~2:1. In contrast, thrombocytopenic mice or mice lacking the extracellular domain of GPIbα ("BSS-like") required very few transfused WT platelets to normalize hemostasis. Both Rasgrp2-/- and GT-like, but not BSS-like, platelets effectively localized to the injury site. Mechanistic studies identified at least two mechanisms of interference by dysfunctional platelets in IPDs: (i) delayed adhesion of WT donor platelets due to reduced access to GPIbα ligands exposed at sites of vascular injury and (ii) impaired consolidation of the hemostatic plug. We also investigated the hemostatic activity of transfused platelets in the setting of dual antiplatelet therapy (DAPT), an acquired platelet function disorder (APD). "DAPT" platelets did not prolong the time to initial hemostasis, but plugs were unstable and frequent rebleeding was observed. Thus, we propose that the endogenous platelet count and the ratio of transfused versus endogenous platelets should be considered when treating select IPD and APD patients with platelet transfusions.
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Affiliation(s)
- Robert H Lee
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA.
- UNC Blood Research Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Raymond Piatt
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Ankita Dhenge
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
- UNC Blood Research Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - María L Lozano
- Servicio de Hematología y Oncología Médica, Hospital Universitario Morales Meseguer, Centro Regional de Hemodonación, Universidad de Murcia, IMIB-Arrixaca, CB15/00055-CIBERER, Murcia 30003, Spain
| | - Verónica Palma-Barqueros
- Servicio de Hematología y Oncología Médica, Hospital Universitario Morales Meseguer, Centro Regional de Hemodonación, Universidad de Murcia, IMIB-Arrixaca, CB15/00055-CIBERER, Murcia 30003, Spain
| | - José Rivera
- Servicio de Hematología y Oncología Médica, Hospital Universitario Morales Meseguer, Centro Regional de Hemodonación, Universidad de Murcia, IMIB-Arrixaca, CB15/00055-CIBERER, Murcia 30003, Spain
| | - Wolfgang Bergmeier
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA.
- UNC Blood Research Center, University of North Carolina, Chapel Hill, NC 27599, USA
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29
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McFadyen JD, Fernando H, Peter K. Off-target drug effects on platelet function: Protecting an Achilles heel of drug development. CURRENT OPINION IN TOXICOLOGY 2019. [DOI: 10.1016/j.cotox.2019.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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30
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Shahbazi S, Mahdian R. Factor VII Gene Defects: Review of Functional Studies and Their Clinical Implications. IRANIAN BIOMEDICAL JOURNAL 2019; 23. [PMID: 30797223 PMCID: PMC6462297 DOI: 10.29252/.23.3.165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Coagulation factors belong to a family of plasma glycosylated proteins that should be activated for appropriate blood coagulation. Congenital deficiencies of these factors cause inheritable hemorrhagic diseases. Factor VII (FVII) deficiency is a rare bleeding disorder with variable clinical symptoms. Various mutations have been identified throughout the F7 gene and can affect all the protein domains. The results of previous experiments have partly revealed the correlation between genotype and phenotype in patients with FVII deficiency. Nevertheless, each particular variant may affect the coagulative function of FVII, mainly via altering its expression level, extra-cellular secretion, tissue factor binding affinity, or proteolytic activity. The pathogenicity of the variants and molecular mechanisms responsible for clinical symptoms in patients with FVII deficiency should be characterized via in silico and in vitro, as well as in vivo functional studies. This review has highlighted the most important functional studies reported on F7 gene variants, including relevant reports regarding Iranian FVII deficiency patients.
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Affiliation(s)
- Shirin Shahbazi
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Reza Mahdian
- Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran,Corresponding Author: Reza Mahdian Molecular Medicine Department, Pasteur Institute of Iran, Tehran, Iran; Tel.& Fax: (+98-21) 64112439; Mobile: (+98-912)7988388; E-mail:
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31
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Brake MA, Ivanciu L, Maroney SA, Martinez ND, Mast AE, Westrick RJ. Assessing Blood Clotting and Coagulation Factors in Mice. ACTA ACUST UNITED AC 2019; 9:e61. [PMID: 30875463 DOI: 10.1002/cpmo.61] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The mammalian blood coagulation system was designed to restrict blood loss due to injury as well as keep the blood fluid within the blood vessels of the organism. Blood coagulation activity in inbred mouse strains varies widely among strains, suggesting that many genomic variants affect hemostasis. Some of these molecules have been discovered and characterized; however, many are still unknown. Genetically modified mouse technologies are providing a plethora of new mouse models for investigating the regulation of blood coagulation. Here we provide a protocol for the tail bleeding time as a primary assessment of in vivo blood coagulation, as well as in vitro methods such as the prothrombin time, activated partial thromboplastin time, and thrombin generation assay. We also provide protocols for the assessment of the activities of specific known factors involved in blood coagulation. © 2019 by John Wiley & Sons, Inc.
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Affiliation(s)
- Marisa A Brake
- Department of Biological Sciences, Oakland University, Rochester, Michigan
| | - Lacramioara Ivanciu
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Divison of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Susan A Maroney
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, Wisconsin
| | - Nicolas D Martinez
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, Wisconsin
| | - Alan E Mast
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, Wisconsin.,Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Randal J Westrick
- Department of Biological Sciences, Oakland University, Rochester, Michigan.,Center for Data Science and Big Data Analysis, Center for Biomedical Research, Oakland University, Rochester, Michigan
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32
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Interrelationships between structure and function during the hemostatic response to injury. Proc Natl Acad Sci U S A 2019; 116:2243-2252. [PMID: 30674670 DOI: 10.1073/pnas.1813642116] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Extensive studies have detailed the molecular regulation of individual components of the hemostatic system, including platelets, coagulation factors, and regulatory proteins. Questions remain, however, about how these elements are integrated at the systems level within a rapidly changing physical environment. To answer some of these questions, we developed a puncture injury model in mouse jugular veins that combines high-resolution, multimodal imaging with functional readouts in vivo. The results reveal striking spatial regulation of platelet activation and fibrin formation that could not be inferred from studies performed ex vivo. As in the microcirculation, where previous studies have been performed, gradients of platelet activation are readily apparent, as is an asymmetrical distribution of fibrin deposition and thrombin activity. Both are oriented from the outer to the inner surface of the damaged vessel wall, with a greater extent of platelet activation and fibrin accumulation on the outside than the inside. Further, we show that the importance of P2Y12 signaling in establishing a competent hemostatic plug is related to the size of the injury, thus limiting its contribution to hemostasis to specific physiologic contexts. Taken together, these studies offer insights into the organization of hemostatic plugs, provide a detailed understanding of the adverse bleeding associated with a widely prescribed class of antiplatelet agents, and highlight differences between hemostasis and thrombosis that may suggest alternative therapeutic approaches.
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33
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Brass LF, Tomaiuolo M, Welsh J, Poventud-Fuentes I, Zhu L, Diamond SL, Stalker TJ. Hemostatic Thrombus Formation in Flowing Blood. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00020-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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34
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Nechipurenko DY, Receveur N, Yakimenko AO, Shepelyuk TO, Yakusheva AA, Kerimov RR, Obydennyy SI, Eckly A, Léon C, Gachet C, Grishchuk EL, Ataullakhanov FI, Mangin PH, Panteleev MA. Clot Contraction Drives the Translocation of Procoagulant Platelets to Thrombus Surface. Arterioscler Thromb Vasc Biol 2019; 39:37-47. [DOI: 10.1161/atvbaha.118.311390] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
After activation at the site of vascular injury, platelets differentiate into 2 subpopulations, exhibiting either proaggregatory or procoagulant phenotype. Although the functional role of proaggregatory platelets is well established, the physiological significance of procoagulant platelets, the dynamics of their formation, and spatial distribution in thrombus remain elusive.
Approach and Results—
Using transmission electron microscopy and fluorescence microscopy of arterial thrombi formed in vivo after ferric chloride–induced injury of carotid artery or mechanical injury of abdominal aorta in mice, we demonstrate that procoagulant platelets are located at the periphery of the formed thrombi. Real-time cell tracking during thrombus formation ex vivo revealed that procoagulant platelets originate from different locations within the thrombus and subsequently translocate towards its periphery. Such redistribution of procoagulant platelets was followed by generation of fibrin at thrombus surface. Using in silico model, we show that the outward translocation of procoagulant platelets can be driven by the contraction of the forming thrombi, which mechanically expels these nonaggregating cells to thrombus periphery. In line with the suggested mechanism, procoagulant platelets failed to translocate and remained inside the thrombi formed ex vivo in blood derived from nonmuscle myosin (
MYH9
)-deficient mice. Ring-like distribution of procoagulant platelets and fibrin around the thrombus observed with blood of humans and wild-type mice was not present in thrombi of
MYH9
-knockout mice, confirming a major role of thrombus contraction in this phenomenon.
Conclusions—
Contraction of arterial thrombus is responsible for the mechanical extrusion of procoagulant platelets to its periphery, leading to heterogeneous structure of thrombus exterior.
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Affiliation(s)
- Dmitry Y. Nechipurenko
- From the Department of Physics, Lomonosov Moscow State University, Russia (D.Y.N., R.R.K., F.I.A., M.A.P.)
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
| | - Nicolas Receveur
- INSERM, Etablissement Français du Sang-Grand Est, UMR_S1255, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, France (N.R., A.E., C.L., C.G., P.H.M.)
| | - Alena O. Yakimenko
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
| | - Taisiya O. Shepelyuk
- Faculty of Basic Medicine, Lomonosov Moscow State University, Russia (T.O.S.)
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
| | - Alexandra A. Yakusheva
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
| | - Roman R. Kerimov
- From the Department of Physics, Lomonosov Moscow State University, Russia (D.Y.N., R.R.K., F.I.A., M.A.P.)
| | - Sergei I. Obydennyy
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
| | - Anita Eckly
- INSERM, Etablissement Français du Sang-Grand Est, UMR_S1255, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, France (N.R., A.E., C.L., C.G., P.H.M.)
| | - Catherine Léon
- INSERM, Etablissement Français du Sang-Grand Est, UMR_S1255, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, France (N.R., A.E., C.L., C.G., P.H.M.)
| | - Christian Gachet
- INSERM, Etablissement Français du Sang-Grand Est, UMR_S1255, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, France (N.R., A.E., C.L., C.G., P.H.M.)
| | - Ekaterina L. Grishchuk
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia (E.L.G.)
| | - Fazoil I. Ataullakhanov
- From the Department of Physics, Lomonosov Moscow State University, Russia (D.Y.N., R.R.K., F.I.A., M.A.P.)
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia (F.I.A., M.A.P.)
| | - Pierre H. Mangin
- INSERM, Etablissement Français du Sang-Grand Est, UMR_S1255, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, France (N.R., A.E., C.L., C.G., P.H.M.)
| | - Mikhail A. Panteleev
- From the Department of Physics, Lomonosov Moscow State University, Russia (D.Y.N., R.R.K., F.I.A., M.A.P.)
- Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia (D.Y.N., A.O.Y., T.O.S., A.A.Y., S.I.O., F.I.A., M.A.P.)
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia (F.I.A., M.A.P.)
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Akbar H, Duan X, Piatt R, Saleem S, Davis AK, Tandon NN, Bergmeier W, Zheng Y. Small molecule targeting the Rac1-NOX2 interaction prevents collagen-related peptide and thrombin-induced reactive oxygen species generation and platelet activation. J Thromb Haemost 2018; 16:2083-2096. [PMID: 30007118 PMCID: PMC6472274 DOI: 10.1111/jth.14240] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Indexed: 12/29/2022]
Abstract
Essentials Reactive oxygen species (ROS) generation by NOX2 plays a critical role in platelet activation. Rac1 regulation of NOX2 is important for ROS generation. Small molecule inhibitor of the Rac1-p67phox interaction prevents platelet activation. Pharmacologic targeting of Rac1-NOX2 axis can be a viable approach for antithrombotic therapy. SUMMARY Background Platelets from patients with X-linked chronic granulomatous disease or mice deficient in nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) oxidase isoform NOX2 exhibit diminished reactive oxygen species (ROS) generation and platelet activation. Binding of Rac1 GTPase to p67phox plays a critical role in NOX2 activation by facilitating the assembly of the NOX2 enzyme complex. Objective We tested the hypothesis that Phox-I, a rationally designed small molecule inhibitor of Rac-p67phox interaction, may serve as an antithrombosis agent by suppressing ROS production and platelet activation. Results Collagen-related peptide (CRP) induced ROS generation in a time-dependent manner. Platelets from Rac1-/- mice or human platelets treated with NSC23766, a specific Rac inhibitor, produced significantly less ROS in response to CRP. Treatment of platelets with Phox-I inhibited diverse CRP-induced responses, including: (i) ROS generation; (ii) release of P-selectin; (iii) secretion of ATP; (iv) platelet aggregation; and (v) phosphorylation of Akt. Similarly, incubation of platelets with Phox-I inhibited thrombin-induced: (i) secretion of ATP; (ii) platelet aggregation; (iii) rise in cytosolic calcium; and (iv) phosphorylation of Akt. In mouse models, intraperitoneal administration of Phox-I inhibited: (i) collagen-induced platelet aggregation without affecting the tail bleeding time and (ii) in vivo platelet adhesion/accumulation at the laser injury sites on the saphenous vein without affecting the time for complete cessation of blood loss. Conclusions Small molecule targeting of the Rac1-p67phox interaction may present an antithrombosis regimen by preventing GPVI- and non-GPVI-mediated NOX2 activation, ROS generation and platelet function without affecting the bleeding time.
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Affiliation(s)
- H Akbar
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - X Duan
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA
| | - R Piatt
- McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, USA
| | - S Saleem
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - A K Davis
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA
| | | | - W Bergmeier
- McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Y Zheng
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA
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Functional redundancy between RAP1 isoforms in murine platelet production and function. Blood 2018; 132:1951-1962. [PMID: 30131434 DOI: 10.1182/blood-2018-03-838714] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 08/11/2018] [Indexed: 01/14/2023] Open
Abstract
RAP GTPases, important regulators of cellular adhesion, are abundant signaling molecules in the platelet/megakaryocytic lineage. However, mice lacking the predominant isoform, RAP1B, display a partial platelet integrin activation defect and have a normal platelet count, suggesting the existence of a RAP1-independent pathway to integrin activation in platelets and a negligible role for RAP GTPases in megakaryocyte biology. To determine the importance of individual RAP isoforms on platelet production and on platelet activation at sites of mechanical injury or vascular leakage, we generated mice with megakaryocyte-specific deletion (mKO) of Rap1a and/or Rap1b Interestingly, Rap1a/b-mKO mice displayed a marked macrothrombocytopenia due to impaired proplatelet formation by megakaryocytes. In platelets, RAP isoforms had redundant and isoform-specific functions. Deletion of RAP1B, but not RAP1A, significantly reduced α-granule secretion and activation of the cytoskeleton regulator RAC1. Both isoforms significantly contributed to thromboxane A2 generation and the inside-out activation of platelet integrins. Combined deficiency of RAP1A and RAP1B markedly impaired platelet aggregation, spreading, and clot retraction. Consistently, thrombus formation in physiological flow conditions was abolished in Rap1a/b-mKO, but not Rap1a-mKO or Rap1b-mKO, platelets. Rap1a/b-mKO mice were strongly protected from experimental thrombosis and exhibited a severe defect in hemostasis after mechanical injury. Surprisingly, Rap1a/b-mKO platelets were indistinguishable from controls in their ability to prevent blood-lymphatic mixing during development and hemorrhage at sites of inflammation. In summary, our studies demonstrate an essential role for RAP1 signaling in platelet integrin activation and a critical role in platelet production. Although important for hemostatic/thrombotic plug formation, platelet RAP1 signaling is dispensable for vascular integrity during development and inflammation.
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Abstract
Clopidogrel is one of the most frequently prescribed drugs worldwide; however, the presence of clopidogrel resistance and high susceptibility to genetic variations and drug interactions are facilitating the development of other antiplatelet drugs. To overcome clopidogrel resistance, several promising clopidogrel analogues have been developed in China, such as vicagrel (and its deuterated analogues), PLD-301, and W1. These novel chemical analogues are all characterized by much faster and more efficient bioconversion to clopidogrel thiolactone (or 2-oxo-clopidogrel, the precursor of clopidogrel active metabolite) in the intestine than clopidogrel itself through bypassing the first-step P450-mediated oxidation of clopidogrel in the liver. Of them, metabolic conversion of vicagrel and PLD-301 to 2-oxo-clopidogrel is catalyzed by intestinal carboxylesterase 2 and alkaline phosphatase, respectively. In this review article, we summarized all evidence on highly efficient bioconversion to their shared precursor of clopidogrel active metabolite and the mechanisms underlying such a pronounced improvement. These drugs in the pipeline would be promising antiplatelet drugs that could be superior to clopidogrel in future patient care.
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Protein kinase C signaling dysfunction in von Willebrand disease (p.V1316M) type 2B platelets. Blood Adv 2018; 2:1417-1428. [PMID: 29925524 DOI: 10.1182/bloodadvances.2017014290] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 05/17/2018] [Indexed: 01/22/2023] Open
Abstract
von Willebrand disease (VWD) type 2B is characterized by gain-of-function mutations in von Willebrand factor (VWF), enhancing its binding affinity for the platelet receptor glycoprotein (GP)Ibα. VWD type 2B patients display a bleeding tendency associated with loss of high-molecular-weight VWF multimers and variable thrombocytopenia. We recently demonstrated that a marked defect in agonist-induced activation of the small GTPase, Rap1, and integrin αIIbβ3 in VWD (p.V1316M) type 2B platelets also contributes to the bleeding tendency. Here, we investigated the molecular mechanisms underlying impaired platelet Rap1 signaling in this disease. Two distinct pathways contribute to Rap1 activation in platelets: rapid activation mediated by the calcium-sensing guanine nucleotide exchange factor CalDAG-GEF-I (CDGI) and sustained activation that is dependent on signaling by protein kinase C (PKC) and the adenosine 5'-diphosphate receptor P2Y12. To investigate which Rap1 signaling pathway is affected, we expressed VWF/p.V1316M by hydrodynamic gene transfer in wild-type and Caldaggef1-/- mice. Using αIIbβ3 integrin activation as a read-out, we demonstrate that platelet dysfunction in VWD (p.V1316M) type 2B affects PKC-mediated, but not CDGI-mediated, activation of Rap1. Consistently, we observed decreased PKC substrate phosphorylation and impaired granule release in stimulated VWD type 2B platelets. Interestingly, the defect in PKC signaling was caused by a significant increase in baseline PKC substrate phosphorylation in circulating VWD (p.V1316M) type 2B platelets, suggesting that the VWF-GPIbα interaction leads to preactivation and exhaustion of the PKC pathway. Consistent with PKC preactivation, VWD (p.V1316M) type 2B mice also exhibited marked shedding of platelet GPIbα. In summary, our studies identify altered PKC signaling as the underlying cause of platelet hypofunction in p.V1316M-associated VWD type 2B.
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Mirramezani M, Herbig BA, Stalker TJ, Nettey L, Cooper M, Weisel JW, Diamond SL, Sinno T, Brass LF, Shadden SC, Tomaiuolo M. Platelet packing density is an independent regulator of the hemostatic response to injury. J Thromb Haemost 2018; 16:973-983. [PMID: 29488682 PMCID: PMC6709675 DOI: 10.1111/jth.13986] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Indexed: 02/01/2023]
Abstract
Essentials Platelet packing density in a hemostatic plug limits molecular movement to diffusion. A diffusion-dependent steep thrombin gradient forms radiating outwards from the injury site. Clot retraction affects the steepness of the gradient by increasing platelet packing density. Together, these effects promote hemostatic plug core formation and inhibit unnecessary growth. SUMMARY Background Hemostasis studies performed in vivo have shown that hemostatic plugs formed after penetrating injuries are characterized by a core of highly activated, densely packed platelets near the injury site, covered by a shell of less activated and loosely packed platelets. Thrombin production occurs near the injury site, further activating platelets and starting the process of platelet mass retraction. Tightening of interplatelet gaps may then prevent the escape and exchange of solutes. Objectives To reconstruct the hemostatic plug macro- and micro-architecture and examine how platelet mass contraction regulates solute transport and solute concentration in the gaps between platelets. Methods Our approach consisted of three parts. First, platelet aggregates formed in vitro under flow were analyzed using scanning electron microscopy to extract data on porosity and gap size distribution. Second, a three-dimensional (3-D) model was constructed with features matching the platelet aggregates formed in vitro. Finally, the 3-D model was integrated with volume and morphology measurements of hemostatic plugs formed in vivo to determine how solutes move within the platelet plug microenvironment. Results The results show that the hemostatic mass is characterized by extremely narrow gaps, porosity values even smaller than previously estimated and stagnant plasma velocity. Importantly, the concentration of a chemical species released within the platelet mass increases as the gaps between platelets shrink. Conclusions Platelet mass retraction provides a physical mechanism to establish steep chemical concentration gradients that determine the extent of platelet activation and account for the core-and-shell architecture observed in vivo.
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Affiliation(s)
- M Mirramezani
- Department of Mechanical Engineering, University of California, Berkeley, CA, USA
| | - B A Herbig
- Department of Chemical and Biomolecular Engineering, Institute for Medicine and Engineering, Philadelphia, PA, USA
| | - T J Stalker
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - L Nettey
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - M Cooper
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - J W Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - S L Diamond
- Department of Chemical and Biomolecular Engineering, Institute for Medicine and Engineering, Philadelphia, PA, USA
| | - T Sinno
- Department of Chemical and Biomolecular Engineering, Institute for Medicine and Engineering, Philadelphia, PA, USA
| | - L F Brass
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - S C Shadden
- Department of Mechanical Engineering, University of California, Berkeley, CA, USA
| | - M Tomaiuolo
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Grover SP, Mackman N. Tissue Factor: An Essential Mediator of Hemostasis and Trigger of Thrombosis. Arterioscler Thromb Vasc Biol 2018; 38:709-725. [PMID: 29437578 DOI: 10.1161/atvbaha.117.309846] [Citation(s) in RCA: 408] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/25/2018] [Indexed: 12/21/2022]
Abstract
Tissue factor (TF) is the high-affinity receptor and cofactor for factor (F)VII/VIIa. The TF-FVIIa complex is the primary initiator of blood coagulation and plays an essential role in hemostasis. TF is expressed on perivascular cells and epithelial cells at organ and body surfaces where it forms a hemostatic barrier. TF also provides additional hemostatic protection to vital organs, such as the brain, lung, and heart. Under pathological conditions, TF can trigger both arterial and venous thrombosis. For instance, atherosclerotic plaques contain high levels of TF on macrophage foam cells and microvesicles that drives thrombus formation after plaque rupture. In sepsis, inducible TF expression on monocytes leads to disseminated intravascular coagulation. In cancer patients, tumors release TF-positive microvesicles into the circulation that may contribute to venous thrombosis. TF also has nonhemostatic roles. For instance, TF-dependent activation of the coagulation cascade generates coagulation proteases, such as FVIIa, FXa, and thrombin, which induce signaling in a variety of cells by cleavage of protease-activated receptors. This review will focus on the roles of TF in protective hemostasis and pathological thrombosis.
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Affiliation(s)
- Steven P Grover
- From the Thrombosis and Hemostasis Program, Division of Hematology and Oncology, Department of Medicine, University of North Carolina at Chapel Hill
| | - Nigel Mackman
- From the Thrombosis and Hemostasis Program, Division of Hematology and Oncology, Department of Medicine, University of North Carolina at Chapel Hill.
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Adili R, Tourdot BE, Mast K, Yeung J, Freedman JC, Green A, Luci DK, Jadhav A, Simeonov A, Maloney DJ, Holman TR, Holinstat M. First Selective 12-LOX Inhibitor, ML355, Impairs Thrombus Formation and Vessel Occlusion In Vivo With Minimal Effects on Hemostasis. Arterioscler Thromb Vasc Biol 2017; 37:1828-1839. [PMID: 28775075 PMCID: PMC5620123 DOI: 10.1161/atvbaha.117.309868] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 07/24/2017] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Adequate platelet reactivity is required for maintaining hemostasis. However, excessive platelet reactivity can also lead to the formation of occlusive thrombi. Platelet 12(S)-lipoxygenase (12-LOX), an oxygenase highly expressed in the platelet, has been demonstrated to regulate platelet function and thrombosis ex vivo, supporting a key role for 12-LOX in the regulation of in vivo thrombosis. However, the ability to pharmacologically target 12-LOX in vivo has not been established to date. Here, we studied the effect of the first highly selective 12-LOX inhibitor, ML355, on in vivo thrombosis and hemostasis. APPROACH AND RESULTS ML355 dose-dependently inhibited human platelet aggregation and 12-LOX oxylipin production, as confirmed by mass spectrometry. Interestingly, the antiplatelet effects of ML355 were reversed after exposure to high concentrations of thrombin in vitro. Ex vivo flow chamber assays confirmed that human platelet adhesion and thrombus formation at arterial shear over collagen were attenuated in whole blood treated with ML355 comparable to aspirin. Oral administration of ML355 in mice showed reasonable plasma drug levels by pharmacokinetic assessment. ML355 treatment impaired thrombus growth and vessel occlusion in FeCl3-induced mesenteric and laser-induced cremaster arteriole thrombosis models in mice. Importantly, hemostatic plug formation and bleeding after treatment with ML355 was minimal in mice in response to laser ablation on the saphenous vein or in a cremaster microvasculature laser-induced rupture model. CONCLUSIONS Our data strongly support 12-LOX as a key determinant of platelet reactivity in vivo, and inhibition of platelet 12-LOX with ML355 may represent a new class of antiplatelet therapy.
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Affiliation(s)
- Reheman Adili
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Benjamin E Tourdot
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Katherine Mast
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Jennifer Yeung
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - John C Freedman
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Abigail Green
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Diane K Luci
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Ajit Jadhav
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Anton Simeonov
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - David J Maloney
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Theodore R Holman
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.)
| | - Michael Holinstat
- From the Department of Pharmacology (R.A., B.E.T., K.M., J.Y., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Chemistry and Biochemistry, University of California Santa Cruz (J.C.F., A.G., T.R.H.); and National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, Rockville, MD (D.K.L., A.J., A.S., D.J.M.).
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Abstract
Actin reorganization regulates key processes in platelet activation. Here we examined the role of the Arp2/3 complex, an essential component in actin filament branching, in platelet function. The Arpc2 gene, encoding the p34 subunit of the Arp2/3 complex, was deleted in the megakaryocyte lineage (Arpc2fl/flPF4-Cre). Deletion of the Arp2/3 complex resulted in marked microthrombocytopenia in mice, caused by premature platelet release into the bone marrow compartment and impaired platelet survival in circulation. Arpc2fl/flPF4-Cre platelets exhibited alterations in their actin cytoskeleton and their peripheral microtubule coil. Thrombocytopenia was alleviated following clodronate liposome-induced macrophage depletion in Arpc2fl/flPF4-Cre mice. Arpc2fl/flPF4-Cre platelets failed to spread and showed a mild defect in integrin activation and aggregation. However, no significant differences in hemostasis or thrombosis were observed between Arpc2fl/flPF4-Cre and control mice. Thus, Arp2/3 is critical for platelet homeostasis but plays only a minor role for vascular hemostasis.
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Miller TP, Li Y, Kavcic M, Getz KD, Huang YSV, Sung L, Alonzo TA, Gerbing R, Daves MH, Horton TM, Pulsipher MA, Pollard J, Bagatell R, Seif AE, Fisher BT, Luger S, Gamis AS, Adamson PC, Aplenc R. Center-level variation in accuracy of adverse event reporting in a clinical trial for pediatric acute myeloid leukemia: a report from the Children's Oncology Group. Haematologica 2017. [PMID: 28642300 DOI: 10.3324/haematol.2017.168815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Tamara P Miller
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Center for Pediatric Clinical Effectiveness, The Children's Hospital of Philadelphia, PA, USA.,Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, PA, USA
| | - Yimei Li
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Center for Clinical Epidemiology and Biostatistics Departments of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Marko Kavcic
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA
| | - Kelly D Getz
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Center for Pediatric Clinical Effectiveness, The Children's Hospital of Philadelphia, PA, USA
| | - Yuan-Shun V Huang
- Center for Pediatric Clinical Effectiveness, The Children's Hospital of Philadelphia, PA, USA
| | - Lillian Sung
- Department of Haematology/Oncology, The Hospital for Sick Children, Toronto, Canada
| | - Todd A Alonzo
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA, USA.,Children's Oncology Group, Monrovia, CA, USA
| | | | - Marla H Daves
- Department of Pediatrics, Section of Hematology-Oncology, Texas Children's Hospital, Houston, TX, USA
| | - Terzah M Horton
- Department of Pediatrics, Section of Hematology-Oncology, Texas Children's Hospital, Houston, TX, USA
| | - Michael A Pulsipher
- Division of Hematology, Oncology and BMT, Children's Hospital of Los Angeles, USC Keck School of Medicine, CA, USA
| | - Jessica Pollard
- Maine Children's Cancer Program, Maine Medical Center, Scarborough, ME, USA
| | - Rochelle Bagatell
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Departments of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Alix E Seif
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Departments of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Brian T Fisher
- Center for Pediatric Clinical Effectiveness, The Children's Hospital of Philadelphia, PA, USA.,Center for Clinical Epidemiology and Biostatistics Departments of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.,Departments of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.,Infectious Diseases, The Children's Hospital of Philadelphia, PA, USA
| | - Selina Luger
- Hematology/Bone Marrow Transplant, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Alan S Gamis
- Pediatric Hematology/Oncology, Children's Mercy Hospital, Kansas City, MO, USA
| | - Peter C Adamson
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA.,Departments of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Richard Aplenc
- Divisions of Oncology, The Children's Hospital of Philadelphia, PA, USA .,Center for Pediatric Clinical Effectiveness, The Children's Hospital of Philadelphia, PA, USA.,Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, PA, USA.,Departments of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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44
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Weiss N, Schenk B, Bachler M, Solomon C, Fries D, Hermann M. FITC-linked Fibrin-Binding Peptide and real-time live confocal microscopy as a novel tool to visualize fibrin(ogen) in coagulation. J Clin Transl Res 2017; 3:276-282. [PMID: 30873479 PMCID: PMC6410668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 05/22/2017] [Accepted: 05/24/2017] [Indexed: 10/25/2022] Open
Abstract
Background and Aim: Although fibrinogen has been established as a key player in the process of coagulation, many questions about the role of fibrinogen under specific conditions remain. Confocal microscopic assessment of clot formation, and in particular the role that fibrinogen plays in this process, is commonly investigated using pre-labeled fibrinogen. This has a number of drawbacks, primarily that it is impossible to stain fibrin networks after their formation. The aim of the present study is to present an alternative for conveniently post-staining fibrin in a wide range of models/situations, in real time and with high resolution. Methods: We combined a peptide known to bind fibrin and linked it to fluorescein isothiocyanate (FITC), creating the FITC-Fibrin-Binding Peptide (FFBP). We subsequently tested its fibrin-binding capability in vitro under static conditions, as well as under simulated flow, using real-time live confocal microscopy. Results: Fibrin stained with FFBP overlaps with fibrin stained with fibrinogen pre-labeled with Alexa Fluor 647 following coagulation induction. In contrast to pre-labeled fibrinogen, FFBP also stains already formed fibrin networks. By combining FFBP with real-time live confocal microscopy even the visualization of single fibrin fibers is possible. Conclusions: These data indicate that FFBP is a valid and valuable tool for real-time live confocal assessment of clot formation. Relevance for patients: Our findings present a valuable alternative for the visualization of fibrin even after its formation, and we believe this approach will be particularly valuable for future investigations of important, but previously overlooked, aspects of clot formation.
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Affiliation(s)
- Nikolaj Weiss
- Department of Anesthesiology and Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Bettina Schenk
- Department of General and Surgical Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Mirjam Bachler
- Institute for Sports Medicine, Alpine Medicine and Health Tourism, UMIT - University for Health Sciences, Medical Informatics and Technology, Hall, Austria
| | - Cristina Solomon
- Department of Anesthesiology, Perioperative Medicine and General Intensive Care, Paracelsus Medical University, Salzburg, Austria, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology and AUVA Research Centre, Vienna, Austria
| | - Dietmar Fries
- Department of General and Surgical Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Martin Hermann
- Department of Anesthesiology and Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
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Welsh JD, Poventud-Fuentes I, Sampietro S, Diamond SL, Stalker TJ, Brass LF. Hierarchical organization of the hemostatic response to penetrating injuries in the mouse macrovasculature. J Thromb Haemost 2017; 15:526-537. [PMID: 27992950 PMCID: PMC5334252 DOI: 10.1111/jth.13600] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/14/2016] [Indexed: 12/27/2022]
Abstract
Essentials Methods were developed to image the hemostatic response in mouse femoral arteries in real time. Penetrating injuries produced thrombi consisting primarily of platelets. Similar to arterioles, a core-shell architecture of platelet activation occurs in the femoral artery. Differences from arterioles included slower platelet activation and reduced thrombin dependence. SUMMARY Background Intravital studies performed in the mouse microcirculation show that hemostatic thrombi formed after penetrating injuries develop a characteristic architecture in which a core of fully activated, densely packed platelets is overlaid with a shell of less activated platelets. Objective Large differences in hemodynamics and vessel wall biology distinguish arteries from arterioles. Here we asked whether these differences affect the hemostatic response and alter the impact of anticoagulants and antiplatelet agents. Methods Approaches previously developed for intravital imaging in the mouse microcirculation were adapted to the femoral artery, enabling real-time fluorescence imaging despite the markedly thicker vessel wall. Results Arterial thrombi initiated by penetrating injuries developed the core-and-shell architecture previously observed in the microcirculation. However, although platelet accumulation was greater in arterial thrombi, the kinetics of platelet activation were slower. Inhibiting platelet ADP P2Y12 receptors destabilized the shell and reduced thrombus size without affecting the core. Inhibiting thrombin with hirudin suppressed fibrin accumulation, but had little impact on thrombus size. Removing the platelet collagen receptor, glycoprotein VI, had no effect. Conclusions These results (i) demonstrate the feasibility of performing high-speed fluorescence imaging in larger vessels and (ii) highlight differences as well as similarities in the hemostatic response in the macro- and microcirculation. Similarities include the overall core-and-shell architecture. Differences include the slower kinetics of platelet activation and a smaller contribution from thrombin, which may be due in part to the greater thickness of the arterial wall and the correspondingly greater separation of tissue factor from the vessel lumen.
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Affiliation(s)
- John D. Welsh
- Departments of Medicine and Pharmacology, University of Pennsylvania, Philadelphia, PA
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA
| | | | - Sara Sampietro
- Departments of Medicine and Pharmacology, University of Pennsylvania, Philadelphia, PA
| | - Scott L. Diamond
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA
| | - Timothy J. Stalker
- Departments of Medicine and Pharmacology, University of Pennsylvania, Philadelphia, PA
| | - Lawrence F. Brass
- Departments of Medicine and Pharmacology, University of Pennsylvania, Philadelphia, PA
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Lee RH, Piatt R, Conley PB, Bergmeier W. Effects of ibrutinib treatment on murine platelet function during inflammation and in primary hemostasis. Haematologica 2016; 102:e89-e92. [PMID: 27979925 DOI: 10.3324/haematol.2016.155978] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Robert H Lee
- McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Raymond Piatt
- McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Wolfgang Bergmeier
- McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA .,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, NC, USA
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47
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Platelets and hemostasis: a new perspective on an old subject. Blood Adv 2016; 1:5-9. [PMID: 29296690 DOI: 10.1182/bloodadvances.2016000059] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 10/03/2016] [Indexed: 01/20/2023] Open
Abstract
Publisher's Note: This article has a companion Counterpoint by Kapur and Semple. Publisher's Note: Join in the discussion of these articles at Blood Advances Community Conversations.
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48
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Schoeman RM, Rana K, Danes N, Lehmann M, Di Paola JA, Fogelson AL, Leiderman K, Neeves KB. A microfluidic model of hemostasis sensitive to platelet function and coagulation. Cell Mol Bioeng 2016; 10:3-15. [PMID: 28529666 DOI: 10.1007/s12195-016-0469-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Hemostasis is the process of sealing a vascular injury with a thrombus to arrest bleeding. The type of thrombus that forms depends on the nature of the injury and hemodynamics. There are many models of intravascular thrombus formation whereby blood is exposed to prothrombotic molecules on a solid substrate. However, there are few models of extravascular thrombus formation whereby blood escapes into the extravascular space through a hole in the vessel wall. Here, we describe a microfluidic model of hemostasis that includes vascular, vessel wall, and extravascular compartments. Type I collagen and tissue factor, which support platelet adhesion and initiate coagulation, respectively, were adsorbed to the wall of the injury channel and act synergistically to yield a stable thrombus that stops blood loss into the extravascular compartment in ~7.5 min. Inhibiting factor VIII to mimic hemophilia A results in an unstable thrombus that was unable to close the injury. Treatment with a P2Y12 antagonist to reduce platelet activation prolonged the closure time two-fold compared to controls. Taken together, these data demonstrate a hemostatic model that is sensitive to both coagulation and platelet function and can be used to study coagulopathies and platelet dysfunction that result in excessive blood loss.
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Affiliation(s)
- R M Schoeman
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO
| | - K Rana
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO
| | - N Danes
- Applied Mathematics and Statistics Department, Colorado School of Mines, Golden, CO
| | - M Lehmann
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO
| | - J A Di Paola
- Department of Pediatrics, University of Colorado Denver, Aurora, CO
| | - A L Fogelson
- Departments of Mathematics and Bioengineering, University of Utah, Salt Lake City, Utah
| | - K Leiderman
- Department of Pediatrics, University of Colorado Denver, Aurora, CO
| | - K B Neeves
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO.,Department of Pediatrics, University of Colorado Denver, Aurora, CO
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49
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Bode MF, Mackman N. A combined deficiency of tissue factor and PAR-4 is associated with fatal pulmonary hemorrhage in mice. Thromb Res 2016; 146:46-50. [PMID: 27586081 DOI: 10.1016/j.thromres.2016.08.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/05/2016] [Accepted: 08/20/2016] [Indexed: 12/01/2022]
Abstract
INTRODUCTION Mice with a complete absence of tissue factor (TF) die during embryonic development whereas mice with low levels of TF (Low-TF mice) survive to adulthood. Low-TF mice exhibit spontaneous hemorrhage in various organs, including the lung. In contrast, mice can survive without protease-activated receptor (PAR)-4, which is the major thrombin receptor on mouse platelets. We determined the effect of combining a deficiency PAR-4 (primary hemostasis) with a deficiency in TF (secondary hemostasis) on embryonic development and survival of adult mice. MATERIALS AND METHODS Low-TF mice (mTF-/-, hTF+/+) were crossed with PAR-4-/- mice to generate heterozygous mice (mTF+/-, hTF+/-, PAR-4+/-). These mice were intercrossed to generate Low-TF mice lacking PAR-4. Mice surviving to wean were genotyped and survival was monitored for 6months. RESULTS We observed the expected number of Low-TF,PAR-4-/- mice at wean indicating survival in utero and after birth. However, an absence of PAR-4 was associated with premature death of all Low-TF,PAR-4-/- mice in the 6month observational period. This compares with 40% death of the Low-TF,PAR-4+/+ mice (p=0.003). Low-TF,PAR-4+/- mice had an intermediate phenotype with 55% of the mice dying within 6months. The primary cause of mortality of Low-TF,PAR-4-/- mice was pulmonary hemorrhage. CONCLUSIONS Low-TF,PAR-4-/- mice survive into adulthood, but combining a deficiency of primary hemostasis (PAR-4 deficiency) with secondary hemostasis (low levels of TF) leads to premature death primarily due to pulmonary hemorrhage.
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Affiliation(s)
- Michael F Bode
- University of North Carolina, Division of Cardiology, Department of Medicine; 160 Dental Circle, CB #7075, 6025 Burnett-Womack-Bldg., Chapel Hill, NC 27514-7075, USA.
| | - Nigel Mackman
- University of North Carolina, Division of Hematology and Oncology, Department of Medicine; McAllister Heart Institute, 111 Mason Farm Road, 2312C Medical Biomolecular Research Bldg., CB #7126, Chapel Hill, NC 27599-7126, USA.
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50
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Piatt R, Paul DS, Lee RH, McKenzie SE, Parise LV, Cowley DO, Cooley BC, Bergmeier W. Mice Expressing Low Levels of CalDAG-GEFI Exhibit Markedly Impaired Platelet Activation With Minor Impact on Hemostasis. Arterioscler Thromb Vasc Biol 2016; 36:1838-46. [PMID: 27417588 DOI: 10.1161/atvbaha.116.307874] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/05/2016] [Indexed: 12/27/2022]
Abstract
OBJECTIVE The tight regulation of platelet adhesiveness, mediated by the αIIbβ3 integrin, is critical for hemostasis and prevention of thrombosis. We recently demonstrated that integrin affinity in platelets is controlled by the guanine nucleotide exchange factor, CalDAG-GEFI (CD-GEFI), and its target, RAP1. In this study, we investigated whether low-level expression of CD-GEFI leads to protection from thrombosis without pathological bleeding in mice. APPROACH AND RESULTS Cdg1(low) mice were generated by knockin of human CD-GEFI cDNA into the mouse Cdg1 locus. CD-GEFI expression in platelets from Cdg1(low) mice was reduced by ≈90% when compared with controls. Activation of RAP1 and αIIbβ3 was abolished at low agonist concentrations and partially inhibited at high agonist concentrations in Cdg1(low) platelets. Consistently, the aggregation response of Cdg1(low) platelets was weaker than that of wild-type platelets, but more efficient than that observed in Cdg1(-/-) platelets. Importantly, Cdg1(low) mice were strongly protected from arterial and immune complex-mediated thrombosis, with only minimal impact on primary hemostasis. CONCLUSIONS Together, our studies suggest the partial inhibition of CD-GEFI function as a powerful new approach to safely prevent thrombotic complications.
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Affiliation(s)
- Raymond Piatt
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - David S Paul
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Robert H Lee
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Steven E McKenzie
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Leslie V Parise
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Dale O Cowley
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Brian C Cooley
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill
| | - Wolfgang Bergmeier
- From the McAllister Heart Institute, University of North Carolina, Chapel Hill (R.P., D.S.P., R.H.L., W.B.); Cardeza Foundation for Hematological Research, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.E.M.); Department of Biochemistry and Biophysics (L.V.P., W.B.), Animal Models Core (D.O.C.), and Rodent Advanced Surgical Core (B.C.C.), University of North Carolina at Chapel Hill.
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