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Avdonin PP, Blinova MS, Serkova AA, Komleva LA, Avdonin PV. Immunity and Coagulation in COVID-19. Int J Mol Sci 2024; 25:11267. [PMID: 39457048 PMCID: PMC11508857 DOI: 10.3390/ijms252011267] [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: 08/19/2024] [Revised: 09/23/2024] [Accepted: 10/15/2024] [Indexed: 10/28/2024] Open
Abstract
Discovered in late 2019, the SARS-CoV-2 coronavirus has caused the largest pandemic of the 21st century, claiming more than seven million lives. In most cases, the COVID-19 disease caused by the SARS-CoV-2 virus is relatively mild and affects only the upper respiratory tract; it most often manifests itself with fever, chills, cough, and sore throat, but also has less-common mild symptoms. In most cases, patients do not require hospitalization, and fully recover. However, in some cases, infection with the SARS-CoV-2 virus leads to the development of a severe form of COVID-19, which is characterized by the development of life-threatening complications affecting not only the lungs, but also other organs and systems. In particular, various forms of thrombotic complications are common among patients with a severe form of COVID-19. The mechanisms for the development of thrombotic complications in COVID-19 remain unclear. Accumulated data indicate that the pathogenesis of severe COVID-19 is based on disruptions in the functioning of various innate immune systems. The key role in the primary response to a viral infection is assigned to two systems. These are the pattern recognition receptors, primarily members of the toll-like receptor (TLR) family, and the complement system. Both systems are the first to engage in the fight against the virus and launch a whole range of mechanisms aimed at its rapid elimination. Normally, their joint activity leads to the destruction of the pathogen and recovery. However, disruptions in the functioning of these innate immune systems in COVID-19 can cause the development of an excessive inflammatory response that is dangerous for the body. In turn, excessive inflammation entails activation of and damage to the vascular endothelium, as well as the development of the hypercoagulable state observed in patients seriously ill with COVID-19. Activation of the endothelium and hypercoagulation lead to the development of thrombosis and, as a result, damage to organs and tissues. Immune-mediated thrombotic complications are termed "immunothrombosis". In this review, we discuss in detail the features of immunothrombosis associated with SARS-CoV-2 infection and its potential underlying mechanisms.
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Affiliation(s)
| | | | | | | | - Pavel V. Avdonin
- Koltzov Institute of Developmental Biology RAS, ul. Vavilova, 26, 119334 Moscow, Russia; (P.P.A.)
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Padín JF, Pérez-Ortiz JM, Redondo-Calvo FJ. Aprotinin (I): Understanding the Role of Host Proteases in COVID-19 and the Importance of Pharmacologically Regulating Their Function. Int J Mol Sci 2024; 25:7553. [PMID: 39062796 PMCID: PMC11277036 DOI: 10.3390/ijms25147553] [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: 05/27/2024] [Revised: 07/06/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
Proteases are produced and released in the mucosal cells of the respiratory tract and have important physiological functions, for example, maintaining airway humidification to allow proper gas exchange. The infectious mechanism of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), takes advantage of host proteases in two ways: to change the spatial conformation of the spike (S) protein via endoproteolysis (e.g., transmembrane serine protease type 2 (TMPRSS2)) and as a target to anchor to epithelial cells (e.g., angiotensin-converting enzyme 2 (ACE2)). This infectious process leads to an imbalance in the mucosa between the release and action of proteases versus regulation by anti-proteases, which contributes to the exacerbation of the inflammatory and prothrombotic response in COVID-19. In this article, we describe the most important proteases that are affected in COVID-19, and how their overactivation affects the three main physiological systems in which they participate: the complement system and the kinin-kallikrein system (KKS), which both form part of the contact system of innate immunity, and the renin-angiotensin-aldosterone system (RAAS). We aim to elucidate the pathophysiological bases of COVID-19 in the context of the imbalance between the action of proteases and anti-proteases to understand the mechanism of aprotinin action (a panprotease inhibitor). In a second-part review, titled "Aprotinin (II): Inhalational Administration for the Treatment of COVID-19 and Other Viral Conditions", we explain in depth the pharmacodynamics, pharmacokinetics, toxicity, and use of aprotinin as an antiviral drug.
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Affiliation(s)
- Juan Fernando Padín
- Department of Medical Sciences, School of Medicine at Ciudad Real, University of Castilla-La Mancha, 13971 Ciudad Real, Spain;
| | - José Manuel Pérez-Ortiz
- Facultad HM de Ciencias de la Salud, Universidad Camilo José Cela, 28692 Madrid, Spain
- Instituto de Investigación Sanitaria HM Hospitales, 28015 Madrid, Spain
| | - Francisco Javier Redondo-Calvo
- Department of Medical Sciences, School of Medicine at Ciudad Real, University of Castilla-La Mancha, 13971 Ciudad Real, Spain;
- Department of Anaesthesiology and Critical Care Medicine, University General Hospital, 13005 Ciudad Real, Spain
- Translational Research Unit, University General Hospital and Research Institute of Castilla-La Mancha (IDISCAM), 13005 Ciudad Real, Spain
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3
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Wang HL, Narisawa M, Wu P, Meng X, Cheng XW. The many roles of cathepsins in restenosis. Heliyon 2024; 10:e24720. [PMID: 38333869 PMCID: PMC10850908 DOI: 10.1016/j.heliyon.2024.e24720] [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] [Received: 09/01/2023] [Revised: 01/12/2024] [Accepted: 01/12/2024] [Indexed: 02/10/2024] Open
Abstract
Drug-eluting stents (DES) and dual antiplatelet regimens have significantly improved the clinical management of ischemic heart disease; however, the drugs loaded with DES in clinical practice are mostly paclitaxel or rapamycin derivatives, which target symptoms of post implantation proliferation and inflammation, leading to delayed re-endothelialization and neo-atherosclerosis. Along with the treatments already in place, there is a need for novel strategies to lessen the negative clinical outcomes of DES delays as well as a need for greater understanding of their pathobiological mechanisms. This review concentrates on the function of cathepsins (Cats) in the inflammatory response and granulation tissue formation that follow Cat-induced damage to the vasculature scaffold, as well as the functions of Cats in intimal hyperplasia, which is characterized by the migration and proliferation of smooth muscle cells, and endothelial denudation, re-endothelialization, and/or neo-endothelialization. Additionally, Cats can alter essential neointima formation and immune response inside scaffolds, and if Cats are properly controlled in vivo, they may improve scaffold biocompatibility. This unique profile of functions could lead to an original concept for a cathepsin-based coronary intervention treatment as an adjunct to stent placement.
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Affiliation(s)
- Hai Long Wang
- Department of Adult Intensive Care Unit, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
- Department of Cardiology and Hypertension, Jilin Provincial Key Laboratory of Stress and Cardiovascular Disease, Yanbian University Hospital, Yanji, Jilin, PR China
| | - Megumi Narisawa
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Aichiken, 4668550, Japan
| | - Pan Wu
- Department of Adult Intensive Care Unit, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Xiangkun Meng
- Department of Vascular Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310000, PR China
| | - Xian Wu Cheng
- Department of Cardiology and Hypertension, Jilin Provincial Key Laboratory of Stress and Cardiovascular Disease, Yanbian University Hospital, Yanji, Jilin, PR China
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, Yanbian University, Yanji, Jilin, 133002, PR China
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4
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Afosah DK, Fayyad RM, Puliafico VR, Merrell S, Langmia EK, Diagne SR, Al-Horani RA, Desai UR. Homogeneous, Synthetic, Non-Saccharide Glycosaminoglycan Mimetics as Potent Inhibitors of Human Cathepsin G. Biomolecules 2023; 13:760. [PMID: 37238630 PMCID: PMC10216581 DOI: 10.3390/biom13050760] [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: 04/12/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Cathepsin G (CatG) is a pro-inflammatory neutrophil serine protease that is important for host defense, and has been implicated in several inflammatory disorders. Hence, inhibition of CatG holds much therapeutic potential; however, only a few inhibitors have been identified to date, and none have reached clinical trials. Of these, heparin is a well-known inhibitor of CatG, but its heterogeneity and bleeding risk reduce its clinical potential. We reasoned that synthetic small mimetics of heparin, labeled as non-saccharide glycosaminoglycan mimetics (NSGMs), would exhibit potent CatG inhibition while being devoid of bleeding risks associated with heparin. Hence, we screened a focused library of 30 NSGMs for CatG inhibition using a chromogenic substrate hydrolysis assay and identified nano- to micro-molar inhibitors with varying levels of efficacy. Of these, a structurally-defined, octasulfated di-quercetin NSGM 25 inhibited CatG with a potency of ~50 nM. NSGM 25 binds to CatG in an allosteric site through an approximately equal contribution of ionic and nonionic forces. Octasulfated 25 exhibits no impact on human plasma clotting, suggesting minimal bleeding risk. Considering that octasulfated 25 also potently inhibits two other pro-inflammatory proteases, human neutrophil elastase and human plasmin, the current results imply the possibility of a multi-pronged anti-inflammatory approach in which these proteases are likely to simultaneously likely combat important conditions, e.g., rheumatoid arthritis, emphysema, or cystic fibrosis, with minimal bleeding risk.
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Affiliation(s)
- Daniel K. Afosah
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Rawan M. Fayyad
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Valerie R. Puliafico
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Spencer Merrell
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Eltice K. Langmia
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Sophie R. Diagne
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Rami A. Al-Horani
- Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, LA 70125, USA
| | - Umesh R. Desai
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
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5
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Colicchia M, Perrella G, Gant P, Rayes J. Novel mechanisms of thrombo-inflammation during infection: spotlight on neutrophil extracellular trap-mediated platelet activation. Res Pract Thromb Haemost 2023; 7:100116. [PMID: 37063765 PMCID: PMC10099327 DOI: 10.1016/j.rpth.2023.100116] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/21/2023] [Accepted: 02/10/2023] [Indexed: 03/13/2023] Open
Abstract
A state-of-the-art lecture titled "novel mechanisms of thrombo-inflammation during infection" was presented at the ISTH Congress in 2022. Platelet, neutrophil, and endothelial cell activation coordinate the development, progression, and resolution of thrombo-inflammatory events during infection. Activated platelets and neutrophil extracellular traps (NETs) are frequently observed in patients with sepsis and COVID-19, and high levels of NET-derived damage-associated molecular patterns (DAMPs) correlate with thrombotic complications. NET-associated DAMPs induce direct and indirect platelet activation, which in return potentiates neutrophil activation and NET formation. These coordinated interactions involve multiple receptors and signaling pathways contributing to vascular and organ damage exacerbating disease severity. This state-of-the-art review describes the main mechanisms by which platelets support NETosis and the key mechanisms by which NET-derived DAMPs trigger platelet activation and the formation of procoagulant platelets leading to thrombosis. We report how these DAMPs act through multiple receptors and signaling pathways differentially regulating cell activation and disease outcome, focusing on histones and S100A8/A9 and their contribution to the pathogenesis of sepsis and COVID-19. We further discuss the complexity of platelet activation during NETosis and the potential benefit of targeting selective or multiple NET-associated DAMPs to limit thrombo-inflammation during infection. Finally, we summarize relevant new data on this topic presented during the 2022 ISTH Congress.
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Affiliation(s)
- Martina Colicchia
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham, U.K
| | - Gina Perrella
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham, U.K
| | - Poppy Gant
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham, U.K
| | - Julie Rayes
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Vincent Drive, Birmingham, U.K
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, The Midlands, U.K
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Wei K, Huang H, Liu M, Shi D, Ma X. Platelet-Derived Exosomes and Atherothrombosis. Front Cardiovasc Med 2022; 9:886132. [PMID: 35498048 PMCID: PMC9051247 DOI: 10.3389/fcvm.2022.886132] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 03/25/2022] [Indexed: 11/17/2022] Open
Abstract
Platelet-derived exosomes (PLT-Exos) are the main subtype of extracellular vesicles secreted by platelets, which carry proteins, nucleotides, lipids, and other substances to acceptor cells, playing an important role in intercellular communication. PLT-Exos increase with platelet activation and are involved in the process of atherothrombosis by delivering cargo to acceptor cells. Atherosclerotic plaque rupture, causing thrombosis and arterial occlusion, is the basic pathological change leading to cardiovascular events. PLT-Exos from different donors have different functions. PLT-Exos secreted by healthy volunteer or mice can inhibit platelet activation and inflammation of endothelial cells, thus exerting an antithrombotic effect, while PLT-Exos derived from some patients induce endothelial apoptosis and an inflammatory response to promote atherothrombosis. Furthermore, increased PLT-Exos reflect platelet activation and their cargoes also are derived from platelets; therefore, PLT-Exos can also be used as a biomarkers for the diagnosis and prognosis of cardiovascular disease. This article reviews the characteristics of PLT-Exos and discusses their role in cell-to-cell communication and atherothrombosis.
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Affiliation(s)
- Kangkang Wei
- National Clinical Research Center for Chinese Medicine Cardiology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Peking University Traditional Chinese Medicine Clinical Medical School (Xiyuan), Beijing, China
- Department of Integrated Chinese and Western Medicine, Peking University Health Science Center, Beijing, China
| | - Hongbo Huang
- National Clinical Research Center for Chinese Medicine Cardiology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing University of Chinese Medicine, Beijing, China
| | - Min Liu
- National Clinical Research Center for Chinese Medicine Cardiology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing University of Chinese Medicine, Beijing, China
| | - Dazhuo Shi
- National Clinical Research Center for Chinese Medicine Cardiology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Peking University Traditional Chinese Medicine Clinical Medical School (Xiyuan), Beijing, China
- Dazhuo Shi,
| | - Xiaojuan Ma
- National Clinical Research Center for Chinese Medicine Cardiology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Xiaojuan Ma,
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7
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Stoller ML, Basak I, Denorme F, Rowley JW, Alsobrooks J, Parsawar K, Nieman MT, Yost CC, Hamilton JR, Bray PF, Campbell RA. Neutrophil cathepsin G proteolysis of protease-activated receptor 4 generates a novel, functional tethered ligand. Blood Adv 2022; 6:2303-2308. [PMID: 34883511 PMCID: PMC9006282 DOI: 10.1182/bloodadvances.2021006133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/16/2021] [Indexed: 12/04/2022] Open
Abstract
Platelet-neutrophil interactions regulate ischemic vascular injury. Platelets are activated by serine proteases that cleave protease-activated receptor (PAR) amino termini, resulting in an activating tethered ligand. Neutrophils release cathepsin G (CatG) at sites of injury and inflammation, which activates PAR4 but not PAR1, although the molecular mechanism of CatG-induced PAR4 activation is unknown. We show that blockade of the canonical PAR4 thrombin cleavage site did not alter CatG-induced platelet aggregation, suggesting CatG cleaves a different site than thrombin. Mass spectrometry analysis using PAR4 N-terminus peptides revealed CatG cleavage at Ser67-Arg68. A synthetic peptide, RALLLGWVPTR, representing the tethered ligand resulting from CatG proteolyzed PAR4, induced PAR4-dependent calcium flux and greater platelet aggregation than the thrombin-generated GYPGQV peptide. Mutating PAR4 Ser67or Arg68 reduced CatG-induced calcium flux without affecting thrombin-induced calcium flux. Dog platelets, which contain a conserved CatG PAR4 Ser-Arg cleavage site, aggregated in response to human CatG and RALLLGWVPTR, while mouse (Ser-Gln) and rat (Ser-Glu) platelets were unresponsive. Thus, CatG amputates the PAR4 thrombin cleavage site by cleavage at Ser67-Arg68 and activates PAR4 by generating a new functional tethered ligand. These findings support PAR4 as an important CatG signaling receptor and suggest a novel therapeutic approach for blocking platelet-neutrophil-mediated pathophysiologies.
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Affiliation(s)
- Michelle L. Stoller
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
| | - Indranil Basak
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Frederik Denorme
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
| | - Jesse W. Rowley
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
- Division of Pulmonary, Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - James Alsobrooks
- Department of Medicine, University of Virginia, Charlottesville, VA
| | - Krishna Parsawar
- Analytical and Biological Mass Spectrometry Core Facility, University of Arizona, Tucson, AZ
| | - Marvin T. Nieman
- Department of Pharmacology, Case Western Reserve University, School of Medicine, Cleveland, OH
| | - Christian Con Yost
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
- Division of Neonatology, Department of Pediatric Medicine, University of Utah, Salt Lake City, UT
| | - Justin R. Hamilton
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia; and
| | - Paul F. Bray
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
- Division of Hematology and Hematologic Malignancies, and
| | - Robert A. Campbell
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City, UT
- Division of General Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, UT
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Tran HDN, Moonshi SS, Xu ZP, Ta HT. Influence of nanoparticles on the haemostatic balance: between thrombosis and haemorrhage. Biomater Sci 2021; 10:10-50. [PMID: 34775503 DOI: 10.1039/d1bm01351c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Maintenance of a delicate haemostatic balance or a balance between clotting and bleeding is critical to human health. Irrespective of administration route, nanoparticles can reach the bloodstream and might interrupt the haemostatic balance by interfering with one or more components of the coagulation, anticoagulation, and fibrinolytic systems, which potentially lead to thrombosis or haemorrhage. However, inadequate understanding of their effects on the haemostatic balance, along with the fact that most studies mainly focus on the functionality of nanoparticles while forgetting or leaving behind their risk to the body's haemostatic balance, is a major concern. Hence, our review aims to provide a comprehensive depiction of nanoparticle-haemostatic balance interactions, which has not yet been covered. The synergistic roles of cells and plasma factors participating in haemostatic balance are presented. Possible interactions and interference of each type of nanoparticle with the haemostatic balance are comprehensively discussed, particularly focusing on the underlying mechanisms. Interactions of nanoparticles with innate immunity potentially linked to haemostasis are mentioned. Various physicochemical characteristics that influence the nanoparticle-haemostatic balance are detailed. Challenges and future directions are also proposed. This insight would be valuable for the establishment of nanoparticles that can either avoid unintended interference with the haemostatic balance or purposely downregulate/upregulate its key components in a controlled manner.
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Affiliation(s)
- Huong D N Tran
- Queensland Micro- and Nanotechnology, Griffith University, Nathan, Queensland 4111, Australia. .,Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, Queensland 4072, Australia
| | | | - Zhi Ping Xu
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Hang Thu Ta
- Queensland Micro- and Nanotechnology, Griffith University, Nathan, Queensland 4111, Australia. .,Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, Queensland 4072, Australia.,School of Environment and Science, Griffith University, Nathan, Queensland 4111, Australia
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9
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Trends in kinase drug discovery: targets, indications and inhibitor design. Nat Rev Drug Discov 2021; 20:839-861. [PMID: 34354255 DOI: 10.1038/s41573-021-00252-y] [Citation(s) in RCA: 338] [Impact Index Per Article: 112.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2021] [Indexed: 02/07/2023]
Abstract
The FDA approval of imatinib in 2001 was a breakthrough in molecularly targeted cancer therapy and heralded the emergence of kinase inhibitors as a key drug class in the oncology area and beyond. Twenty years on, this article analyses the landscape of approved and investigational therapies that target kinases and trends within it, including the most popular targets of kinase inhibitors and their expanding range of indications. There are currently 71 small-molecule kinase inhibitors (SMKIs) approved by the FDA and an additional 16 SMKIs approved by other regulatory agencies. Although oncology is still the predominant area for their application, there have been important approvals for indications such as rheumatoid arthritis, and one-third of the SMKIs in clinical development address disorders beyond oncology. Information on clinical trials of SMKIs reveals that approximately 110 novel kinases are currently being explored as targets, which together with the approximately 45 targets of approved kinase inhibitors represent only about 30% of the human kinome, indicating that there are still substantial unexplored opportunities for this drug class. We also discuss trends in kinase inhibitor design, including the development of allosteric and covalent inhibitors, bifunctional inhibitors and chemical degraders.
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10
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Alkarithi G, Duval C, Shi Y, Macrae FL, Ariëns RAS. Thrombus Structural Composition in Cardiovascular Disease. Arterioscler Thromb Vasc Biol 2021; 41:2370-2383. [PMID: 34261330 PMCID: PMC8384252 DOI: 10.1161/atvbaha.120.315754] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Thrombosis is a major complication of cardiovascular disease, leading to myocardial infarction, acute ischemic stroke, or venous thromboembolism. Thrombosis occurs when a thrombus forms inside blood vessels disrupting blood flow. Developments in thrombectomy to remove thrombi from vessels have provided new opportunities to study thrombus composition which may help to understand mechanisms of disease and underpin improvements in treatments. We aimed to review thrombus compositions, roles of components in thrombus formation and stability, and methods to investigate thrombi. Also, we summarize studies on thrombus structure obtained from cardiovascular patients and animal models. Thrombi are composed of fibrin, red blood cells, platelets, leukocytes, and neutrophil extracellular traps. These components have been analyzed by several techniques, including scanning electron microscopy, laser scanning confocal microscopy, histochemistry, and immunohistochemistry; however, each technique has advantages and limitations. Thrombi are heterogenous in composition, but overall, thrombi obtained from myocardial infarction are composed of mainly fibrin and other components, including platelets, red blood cells, leukocytes, and cholesterol crystals. Thrombi from patients with acute ischemic stroke are characterized by red blood cell- and platelet-rich regions. Thrombi from patients with venous thromboembolism contain mainly red blood cells and fibrin with some platelets and leukocytes. Thrombus composition from patients with myocardial infarction is influenced by ischemic time. Animal thrombosis models are crucial to gain further mechanistic information about thrombosis and thrombus structure, with thrombi being similar in composition compared with those from patients. Further studies on thrombus composition and function are key to improve treatment and clinical outcome of thrombosis.
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Affiliation(s)
- Ghadir Alkarithi
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (G.A., C.D., Y.S., F.L.M., R.A.S.A.).,Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia (G.A.)
| | - Cédric Duval
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (G.A., C.D., Y.S., F.L.M., R.A.S.A.)
| | - Yu Shi
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (G.A., C.D., Y.S., F.L.M., R.A.S.A.)
| | - Fraser L Macrae
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (G.A., C.D., Y.S., F.L.M., R.A.S.A.)
| | - Robert A S Ariëns
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom (G.A., C.D., Y.S., F.L.M., R.A.S.A.)
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11
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Shi Y, Gauer JS, Baker SR, Philippou H, Connell SD, Ariëns RAS. Neutrophils can promote clotting via FXI and impact clot structure via neutrophil extracellular traps in a distinctive manner in vitro. Sci Rep 2021; 11:1718. [PMID: 33462294 PMCID: PMC7814028 DOI: 10.1038/s41598-021-81268-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/04/2021] [Indexed: 12/23/2022] Open
Abstract
Neutrophils and neutrophil extracellular traps (NETs) have been shown to be involved in coagulation. However, the interactions between neutrophils or NETs and fibrin(ogen) in clots, and the mechanisms behind these interactions are not yet fully understood. In this in vitro study, the role of neutrophils or NETs on clot structure, formation and dissolution was studied with a combination of confocal microscopy, turbidity and permeation experiments. Factor (F)XII, FXI and FVII-deficient plasmas were used to investigate which factors may be involved in the procoagulant effects. We found both neutrophils and NETs promote clotting in plasma without the addition of other coagulation triggers, but not in purified fibrinogen, indicating that other factors mediate the interaction. The procoagulant effects of neutrophils and NETs were also observed in FXII- and FVII-deficient plasma. In FXI-deficient plasma, only the procoagulant effects of NETs were observed, but not of neutrophils. NETs increased the density of clots, particularly in the vicinity of the NETs, while neutrophils-induced clots were less stable and more porous. In conclusion, NETs accelerate clotting and contribute to the formation of a denser, more lysis resistant clot architecture. Neutrophils, or their released mediators, may induce clotting in a different manner to NETs, mediated by FXI.
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Affiliation(s)
- Y Shi
- LIGHT Laboratories, Discovery and Translational Science Department, Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Clarendon Way, Leeds, LS2 9LU, UK
| | - J S Gauer
- LIGHT Laboratories, Discovery and Translational Science Department, Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Clarendon Way, Leeds, LS2 9LU, UK
| | - S R Baker
- LIGHT Laboratories, Discovery and Translational Science Department, Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Clarendon Way, Leeds, LS2 9LU, UK
- Department of Physics, Wake Forest University, Winston Salem, NC, USA
| | - H Philippou
- LIGHT Laboratories, Discovery and Translational Science Department, Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Clarendon Way, Leeds, LS2 9LU, UK
| | - S D Connell
- The Astbury Centre for Structural Molecular Biology, Molecular & Nanoscale Physics, University of Leeds, Leeds, LS2 9JT, UK
| | - R A S Ariëns
- LIGHT Laboratories, Discovery and Translational Science Department, Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Clarendon Way, Leeds, LS2 9LU, UK.
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Sánchez Di Maggio L, Tirloni L, Uhl M, Carmona C, Logullo C, Mulenga A, da Silva Vaz I, Berasain P. Serpins in Fasciola hepatica: insights into host-parasite interactions. Int J Parasitol 2020; 50:931-943. [PMID: 32668271 DOI: 10.1016/j.ijpara.2020.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 05/14/2020] [Accepted: 05/20/2020] [Indexed: 12/28/2022]
Abstract
Protease inhibitors play crucial roles in parasite development and survival, modulating the immune responses of their vertebrate hosts. Members of the serpin family are irreversible inhibitors of serine proteases and regulate systems related to defence against parasites. Limited information is currently available on protease inhibitors from the liver fluke Fasciola hepatica. In this study, we characterised four serpins from F. hepatica (FhS-1-FhS-4). Biochemical characterisation revealed that recombinant FhS-2 (rFhS) inhibits the activity of human neutrophil cathepsin G, while rFhS-4 inhibits the activity of bovine pancreatic chymotrypsin and cathepsin G. Consistent with inhibitor function profiling data, rFhS-4 inhibited cathepsin G-activated platelet aggregation in a dose-responsive manner.Similar to other serpins, rFhS2 and rFhS-4 bind to heparin with high affinity. Tissue localisation demonstrated that these serpins have different spatial distributions. FhS-2 is localised in the ovary, while FhS-4 was found in gut cells. Both of them co-localised in the spines within the tegument. These findings provide the basis for study of functional roles of these proteins as part of an immune evasion mechanism in the adult fluke, and in protection of eggs to ensure parasite life cycle continuity. Further understanding of serpins from the liver fluke may lead to the discovery of novel anti-parasitic interventions.
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Affiliation(s)
- Lucía Sánchez Di Maggio
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Unidad de Biología Parasitaria, Facultad de Ciencias, Universidad de la República Oriental del Uruguay, Montevideo, Uruguay
| | - Lucas Tirloni
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, USA
| | - Marcelle Uhl
- Laboratory of Chemistry and Function of Proteins and Peptides, Animal Experimentation Unit, Universidade Estadual do Norte Fluminence Darcy Ribeiro, Campos dos Goytacazes, RJ, Brazil
| | - Carlos Carmona
- Unidad de Biología Parasitaria, Facultad de Ciencias, Universidad de la República Oriental del Uruguay, Montevideo, Uruguay
| | - Carlos Logullo
- Laboratory of Chemistry and Function of Proteins and Peptides, Animal Experimentation Unit, Universidade Estadual do Norte Fluminence Darcy Ribeiro, Campos dos Goytacazes, RJ, Brazil
| | - Albert Mulenga
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, USA
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Patrícia Berasain
- Unidad de Biología Parasitaria, Facultad de Ciencias, Universidad de la República Oriental del Uruguay, Montevideo, Uruguay.
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Ratajczak-Wrona W, Nowak K, Garley M, Grubczak K, Dabrowska D, Iwaniuk A, Wilk S, Moniuszko M, Czerniecki J, Wolczynski S, Jablonska E. Expression of serine proteases in neutrophils from women and men: Regulation by endocrine disruptor bisphenol A. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2019; 71:103212. [PMID: 31247398 DOI: 10.1016/j.etap.2019.103212] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 06/10/2019] [Accepted: 06/17/2019] [Indexed: 05/22/2023]
Abstract
Bisphenol A (BPA) is a well-known endocrine disruptor. However, little information is available about its immunological effects. In the present study, we aimed to evaluate cytotoxic activity of BPA on human polymorphonuclear neutrophils (PMNs) according to gender and examine its effect on the expression of neutrophil serine proteases. Results indicated that exposure to BPA (above 16 μM) leads to a decrease in viability of PMNs and to morphological changes in these cells of both genders. The experiments showed different effects of BPA on the expression of proteinase 3, elastase, and cathepsin G in PMNs of both men and women, depending on the gender and concentration used. Thus, our findings suggest for the first time that through dysregulation of the expression of these enzymes, BPA may lead to disorders of the nonspecific cellular response in people exposed to this xenoestrogen.
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Affiliation(s)
| | - Karolina Nowak
- Department of Immunology, Medical University of Bialystok, Poland
| | - Marzena Garley
- Department of Immunology, Medical University of Bialystok, Poland
| | - Kamil Grubczak
- Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, Poland
| | - Dorota Dabrowska
- Department of Immunology, Medical University of Bialystok, Poland
| | | | - Sara Wilk
- Department of Immunology, Medical University of Bialystok, Poland
| | - Marcin Moniuszko
- Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, Poland; Department of Allergology and Internal Medicine, Medical University of Bialystok, Poland
| | - Jan Czerniecki
- Department of Biology and Pathology of Human Reproduction, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
| | - Slawomir Wolczynski
- Department of Biology and Pathology of Human Reproduction, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland; Department of Reproduction and Gynecological Endocrinology, Medical University of Bialystok, Bialystok, Poland
| | - Ewa Jablonska
- Department of Immunology, Medical University of Bialystok, Poland
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Huskens D, Sang Y, Konings J, van der Vorm L, de Laat B, Kelchtermans H, Roest M. Standardization and reference ranges for whole blood platelet function measurements using a flow cytometric platelet activation test. PLoS One 2018; 13:e0192079. [PMID: 29389990 PMCID: PMC5794146 DOI: 10.1371/journal.pone.0192079] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 01/16/2018] [Indexed: 01/19/2023] Open
Abstract
Introduction Platelet function testing with flow cytometry has additional value to existing platelet function testing for diagnosing bleeding disorders, monitoring anti-platelet therapy, transfusion medicine and prediction of thrombosis. The major challenge is to use this technique as a diagnostic test. The aim of this study is to standardize preparation, optimization and validation of the test kit and to determine reference values in a population of 129 healthy individuals. Methods Platelet function tests with 3 agonists and antibodies against P-selectin, activated αIIbβ3 and glycoprotein Ib (GPIb), were prepared and stored at -20°C until used. Diluted whole blood was added and platelet activation was quantified by the density of activation markers, using flow cytometry. Anti-mouse Ig κ particles were included to validate stability of the test and to standardize results. Reference intervals were determined. Results Blood stored at room temperature (RT) for up to 4h after blood donation and preheated/tested at 37°C resulted in stable results (%CV<10%), in contrast to measuring at RT. The intra-assay %CV was <5%. Incubation of anti-mouse Ig κ particles with antibodies stored for up to 12 months proved to give a stable fluorescence. The inter-individual variation measured in the 129 individuals varied between 23% and 37% for P-selectin expression and αIIbβ3 activation, respectively. Conclusions The current study contributes to the translation of flow cytometry based platelet function testing from a scientific tool to a diagnostic test. Platelet function measurements, using prepared and stored platelet activation kits, are reproducible if executed at 37°C. The reference ranges can be validated in clinical laboratories and ongoing studies are investigating if reduced platelet reactivity in patients with bleeding complications can be detected.
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Affiliation(s)
- Dana Huskens
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
- * E-mail:
| | - Yaqiu Sang
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
| | - Joke Konings
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
| | - Lisa van der Vorm
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
- Department of Clinical Chemistry and Hematology, Gelre Hospitals, Apeldoorn, The Netherlands
| | - Bas de Laat
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
| | - Hilde Kelchtermans
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
| | - Mark Roest
- Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, the Netherlands
- Synapse Research Institute, Maastricht, the Netherlands
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Dikshit M, Kumari R. Modulation of Platelet Aggregation Response by Factors Released from Polymorphonuclear Leukocytes. Hematology 2016; 2:39-53. [DOI: 10.1080/10245332.1997.11746318] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Madhu Dikshit
- Pharmacology Division, Central Druo Research Institute, Lucknow-226001 India
| | - Ranjana Kumari
- Pharmacology Division, Central Druo Research Institute, Lucknow-226001 India
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Abstract
In recent years, the traditional view of the hemostatic system as being regulated by a coagulation factor cascade coupled with platelet activation has been increasingly challenged by new evidence that activation of the immune system strongly influences blood coagulation and pathological thrombus formation. Leukocytes can be induced to express tissue factor and release proinflammatory and procoagulant molecules such as granular enzymes, cytokines, and damage-associated molecular patterns. These mediators can influence all aspects of thrombus formation, including platelet activation and adhesion, and activation of the intrinsic and extrinsic coagulation pathways. Leukocyte-released procoagulant mediators increase systemic thrombogenicity, and leukocytes are actively recruited to the site of thrombus formation through interactions with platelets and endothelial cell adhesion molecules. Additionally, phagocytic leukocytes are involved in fibrinolysis and thrombus resolution, and can regulate clearance of platelets and coagulation factors. Dysregulated activation of leukocyte innate immune functions thus plays a role in pathological thrombus formation. Modulation of the interactions between leukocytes or leukocyte-derived procoagulant materials and the traditional hemostatic system is an attractive target for the development of novel antithrombotic strategies.
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18
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Page C, Pitchford S. Neutrophil and platelet complexes and their relevance to neutrophil recruitment and activation. Int Immunopharmacol 2013; 17:1176-84. [PMID: 23810443 DOI: 10.1016/j.intimp.2013.06.004] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Revised: 09/20/2012] [Accepted: 06/09/2013] [Indexed: 12/29/2022]
Abstract
The manifestation of platelet 'satallitism' around neutrophils in whole blood is a long acknowledged phenomenon [1]. Circulating platelet-neutrophil complexes (PNC) occur in a diverse range of inflammatory disorders and infections that affect numerous organs of the body. Animal models have revealed that the formation of PNC is required for the recruitment of neutrophils to inflamed tissue, since platelets 'prime' neutrophils for efficient adhesion to vascular endothelium via the up-regulation of integrins and enhanced responsiveness to chemokines (Fig. 1). Perhaps surprisingly, the surface contact between platelets and neutrophils additionally enhances other neutrophil functions, such as chemotaxis that is required for migration into tissues, trans-cellular production of eicosanoids, phagocytosis and trapping of pathogens, increased respiratory burst leading to the production of reactive oxygen species (ROS), and modulation of neutrophil apoptosis (Fig. 1). Platelet P-selectin appears to have a particular role in enhancing the majority of these activities, and the influence of platelet P-selectin is not therefore confined to the initial rolling events in the process of neutrophil extravasation.
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Affiliation(s)
- Clive Page
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, Kings College London, London SE1 9NH, UK
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Taylor ML, Misso NL, Stewart GA, Thompson PJ. Differential Expression of Platelet Activation Markers CD62P and CD63 Following Stimulation with PAF, Arachidonic Acid and Collagen. Platelets 2012; 6:394-401. [PMID: 21043771 DOI: 10.3109/09537109509078478] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The effects of varying concentrations of platelet-activating factor (PAF), arachidonic acid (AA) and collagen on the expression of the platelet activation markers CD63 and CD62P were assessed in 10 normal subjects using flow cytometry. CD63 expression was significantly greater than CD62P expression, with PAF (80 nM) inducing mean maximum CD63 expression of 32.9 ± 6.4% and mean maximum CD62P expression of 5.5 ± 1.8%. AA (1 mM) induced maximum CD63 expression of 37.7 ± 7% and maximum CD62P expression of 9.3 ± 1%. Collagen (2-80 pg/ml) induced minimal expression but 800 pg/ml induced mean CD63 expression of 33.1 ± 4.1% and mean CD62P expression of 6.1 ± 0.8%. Greater CD63 and CD62P expression were induced by phorbol myristate acetate (1.6 pM, 70.9 ± 11% and 69.4 ± 9.9%, respectively) and thrombin (0.1 U/ml, 70.7 ± 9.3% and 73.5 ± 5.4%, respectively). With PAF and collagen only one platelet population was detected whereas with 1 mM AA two populations were observed. These results indicate that expression of platelet adhesion receptors depends on the nature and concentration of agonist and that subpopulations of platelets may exist. Importantly, PAF concentrations inducing moderate CD63 and CD62P expression did not induce platelet aggregation, suggesting that platelets can be activated independently of aggregation.
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Affiliation(s)
- M L Taylor
- Thompson, Asthma and Allergy Research Unit, Department of Medicine, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands, WA, 6009, Australia
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Gardiner EE, Andrews RK. Neutrophil extracellular traps (NETs) and infection-related vascular dysfunction. Blood Rev 2012; 26:255-9. [PMID: 23021640 DOI: 10.1016/j.blre.2012.09.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The innate immune system orchestrated by leukocytes primarily neutrophils, serves to remove dead and dying host cells and to provide protection against invasion by pathogens. Failure of this system results in the onset of sepsis leading to grave consequences for the host. Together with mechanical methods to physically isolate and remove the pathogen, neutrophils also release an important set of proinflammatory biological modulators that mediate recruitment of additional cells to a site of infection and amplify the innate protective response. Additionally, neutrophils release highly charged mixtures of DNA and nuclear proteins named neutrophil extracellular traps (NETs). These electrostatically-charged adhesive networks trigger intrinsic coagulation, limit dispersion and entrap the pathogens. NETs also contain the neutrophil secretary granule-derived serine proteases, neutrophil elastase and cathepsin G, known to regulate the reactivity of both neutrophils and platelets. Since the characterization of NETs in 2004, new studies of their functional effect in vivo continue to expand upon unexpected extracellular roles for DNA, and in doing so renew attention to the haemostatic role of the leukocyte. This review will provide a basic description of NETs and examine current knowledge of this important system of defense, including recent work illustrating a role for NETs in activation of thrombosis.
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Mäntylä P, Buduneli E, Emingil G, Tervahartiala T, Pussinen PJ, Barış N, Akıllı A, Atilla G, Sorsa T. Acute myocardial infarction elevates serine protease activity in saliva of patients with periodontitis. J Periodontal Res 2011; 47:345-53. [DOI: 10.1111/j.1600-0765.2011.01439.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Borissoff JI, ten Cate H. From neutrophil extracellular traps release to thrombosis: an overshooting host-defense mechanism? J Thromb Haemost 2011; 9:1791-4. [PMID: 21718435 DOI: 10.1111/j.1538-7836.2011.04425.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- J I Borissoff
- Laboratory for Clinical Thrombosis and Hemostasis, Department of Internal Medicine and Biochemistry, Cardiovascular Research Institute of Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands
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Carcinoma mucins trigger reciprocal activation of platelets and neutrophils in a murine model of Trousseau syndrome. Blood 2011; 118:4015-23. [PMID: 21860019 DOI: 10.1182/blood-2011-07-368514] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Trousseau syndrome is classically defined as migratory, heparin-sensitive but warfarin-resistant microthrombi in patients with occult, mucinous adenocarcinomas. Injecting carcinoma mucins into mice generates platelet-rich microthrombi dependent on P- and L-selectin but not thrombin. Heparin prevents mucin binding to P- and L-selectin and mucin-induced microthrombi. This model of Trousseau syndrome explains resistance to warfarin, which inhibits fluid-phase coagulation but not selectins. Here we found that carcinoma mucins do not generate microthrombi in mice lacking P-selectin glycoprotein ligand-1 (PSGL-1), the leukocyte ligand for P- and L-selectin. Furthermore, mucins did not activate platelets in blood from PSGL-1-deficient mice. Mucins induced microthrombi in radiation chimeras lacking endothelial P-selectin but not in chimeras lacking platelet P-selectin. Mucins caused leukocytes to release cathepsin G, but only if platelets were present. Mucins failed to generate microthrombi in cathepsin G-deficient mice. Mucins did not activate platelets in blood from mice lacking cathepsin G or protease-activated receptor-4 (PAR4), indicating that cathepsin G activates platelets through PAR4. Using knockout mice and blocking antibodies, we found that mucin-triggered cathepsin G release requires L-selectin and PSGL-1 on neutrophils, P-selectin on platelets, and Src family kinases in both cell types. Thus, carcinoma mucins promote thrombosis through adhesion-dependent, bidirectional signaling in neutrophils and platelets.
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Burster T, Macmillan H, Hou T, Boehm BO, Mellins ED. Cathepsin G: roles in antigen presentation and beyond. Mol Immunol 2009; 47:658-65. [PMID: 19910052 DOI: 10.1016/j.molimm.2009.10.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 10/02/2009] [Accepted: 10/06/2009] [Indexed: 12/19/2022]
Abstract
Contributions from multiple cathepsins within endosomal antigen processing compartments are necessary to process antigenic proteins into antigenic peptides. Cysteine and aspartyl cathepsins have been known to digest antigenic proteins. A role for the serine protease, cathepsin G (CatG), in this process has been described only recently, although CatG has long been known to be a granule-associated proteolytic enzyme of neutrophils. In line with a role for this enzyme in antigen presentation, CatG is found in endocytic compartments of a variety of antigen presenting cells. CatG is found in primary human monocytes, B cells, myeloid dendritic cells 1 (mDC1), mDC2, plasmacytoid DC (pDC), and murine microglia, but is not expressed in B cell lines or monocyte-derived DC. Purified CatG can be internalized into endocytic compartments in CatG non-expressing cells, widening the range of cells where this enzyme may play a role in antigen processing. Functional assays have implicated CatG as a critical enzyme in processing of several antigens and autoantigens. In this review, historical and recent data on CatG expression, distribution, function and involvement in disease will be summarized and discussed, with a focus on its role in antigen presentation and immune-related events.
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Affiliation(s)
- Timo Burster
- Division of Endocrinology and Diabetes, Department of Internal Medicine I, Ulm University, Ulm, Germany.
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Wang H, Zhang W, Tang R, Hebbel RP, Kowalska MA, Zhang C, Marth JD, Fukuda M, Zhu C, Huo Y. Core2 1-6-N-glucosaminyltransferase-I deficiency protects injured arteries from neointima formation in ApoE-deficient mice. Arterioscler Thromb Vasc Biol 2009; 29:1053-9. [PMID: 19372458 DOI: 10.1161/atvbaha.109.187716] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Core2 1 to 6-N-glucosaminyltransferase-I (C2GlcNAcT-I) plays an important role in optimizing the binding functions of several selectin ligands, including P-selectin glycoprotein ligand. We used apolipoprotein E (ApoE)-deficient atherosclerotic mice to investigate the role of C2GlcNAcT-I in platelet and leukocyte interactions with injured arterial walls, in endothelial regeneration at injured sites, and in the formation of arterial neointima. METHODS AND RESULTS Arterial neointima induced by wire injury was smaller in C2GlcNAcT-I-deficient apoE(-/-) mice than in control apoE(-/-) mice (a 79% reduction in size). Compared to controls, apoE(-/-) mice deficient in C2GlcNAcT-I also demonstrated less leukocyte adhesion on activated platelets in microflow chambers (a 75% reduction), and accumulation of leukocytes at injured areas of mouse carotid arteries was eliminated. Additionally, endothelial regeneration in injured lumenal areas was substantially faster in C2GlcNAcT-I-deficient apoE(-/-) mice than in control apoE(-/-) mice. Endothelial regeneration was associated with reduced accumulation of platelet factor 4 (PF4) at injured sites. PF4 deficiency accelerated endothelial regeneration and protected mice from neointima formation after arterial injury. CONCLUSIONS C2GlcNAcT-I deficiency suppresses injury-induced arterial neointima formation, and this effect is attributable to decreased leukocyte recruitment to injured vascular walls and increased endothelial regeneration. Both C2GlcNAcT-I and PF4 are promising targets for the treatment of arterial restenosis.
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Affiliation(s)
- Huan Wang
- Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Gorog DA, Sweeny JM, Fuster V. Antiplatelet drug 'resistance'. Part 2: laboratory resistance to antiplatelet drugs—fact or artifact? Nat Rev Cardiol 2009; 6:365-73. [DOI: 10.1038/nrcardio.2009.13] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lim YA, Cho SR, Lee WG, Park JS, Kim SW. Change of platelet activation markers using flow cytometry in patients with hematology/oncology disorders after transfusion. Platelets 2008; 19:328-34. [PMID: 18791938 DOI: 10.1080/09537100802129867] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
In spite of the frequent need of platelet transfusions, there is limited information on the association of platelet activation markers, in transfused patients with hematology/oncology disorders, with platelet function using flow cytometry. The goal of this study was to evaluate the changes of PAC-1 binding and CD62P expression, with or without agonists in patients after transfusions. Twenty-eight whole blood samples were obtained from 24 patients admitted to the department of Hematology & Oncology and transfused with platelets; these samples were compared to 30 healthy controls. Whole blood samples, either with or without agonists, such as 20 microM adenosine diphosphate (ADP) or 100 microM thrombin receptor activating peptide (TRAP), were stained with the fluorescein conjugated monoclonal antibodies PAC-1 or CD62P. Then, the percent expression for each marker was analysed using flow cytometry. ADP and TRAP induced an increased percentage of CD62P expression and PAC-1 binding after platelet transfusions compared to the samples studied before transfusion, and these findings were lower than those of the healthy controls. However, the expression of platelets without the agonists was not significantly changed, despite the transfusions. Therefore, agonist-induced platelet activation markers, studied by flow cytometry, appear to be more useful for the evaluation of platelet function after transfusions than platelet activation markers without agonists.
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Affiliation(s)
- Young Ae Lim
- Departments of Laboratory Medicine, Ajou University School of Medicine, Suwon, Korea.
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Gatto B, Vianini E, Lucatello L, Sissi C, Moltrasio D, Pescador R, Porta R, Palumbo M. Effective DNA inhibitors of cathepsin g by in vitro selection. Int J Mol Sci 2008; 9:1008-1023. [PMID: 19325843 PMCID: PMC2658781 DOI: 10.3390/ijms9061008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 06/06/2008] [Accepted: 06/10/2008] [Indexed: 11/16/2022] Open
Abstract
Cathepsin G (CatG) is a chymotrypsin-like protease released upon degranulation of neutrophils. In several inflammatory and ischaemic diseases the impaired balance between CatG and its physiological inhibitors leads to tissue destruction and platelet aggregation. Inhibitors of CatG are suitable for the treatment of inflammatory diseases and procoagulant conditions. DNA released upon the death of neutrophils at injury sites binds CatG. Moreover, short DNA fragments are more inhibitory than genomic DNA. Defibrotide, a single stranded polydeoxyribonucleotide with antithrombotic effect is also a potent CatG inhibitor. Given the above experimental evidences we employed a selection protocol to assess whether DNA inhibition of CatG may be ascribed to specific sequences present in defibrotide DNA. A Selex protocol was applied to identify the single-stranded DNA sequences exhibiting the highest affinity for CatG, the diversity of a combinatorial pool of oligodeoxyribonucleotides being a good representation of the complexity found in defibrotide. Biophysical and biochemical studies confirmed that the selected sequences bind tightly to the target enzyme and also efficiently inhibit its catalytic activity. Sequence analysis carried out to unveil a motif responsible for CatG recognition showed a recurrence of alternating TG repeats in the selected CatG binders, adopting an extended conformation that grants maximal interaction with the highly charged protein surface. This unprecedented finding is validated by our results showing high affinity and inhibition of CatG by specific DNA sequences of variable length designed to maximally reduce pairing/folding interactions.
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Affiliation(s)
- Barbara Gatto
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
- Author to whom correspondence should be addressed; E-mail:
| | - Elena Vianini
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Lorena Lucatello
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Claudia Sissi
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Danilo Moltrasio
- Gentium S.p.A., Piazza XX Settembre 2, 22079 Villa Guardia, Italy
| | - Rodolfo Pescador
- Gentium S.p.A., Piazza XX Settembre 2, 22079 Villa Guardia, Italy
| | - Roberto Porta
- Gentium S.p.A., Piazza XX Settembre 2, 22079 Villa Guardia, Italy
| | - Manlio Palumbo
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
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Michelson AD, Linden MD, Barnard MR, Furman MI, Frelinger A. Flow Cytometry. Platelets 2007. [DOI: 10.1016/b978-012369367-9/50792-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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32
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Kayo S, Ikura Y, Suekane T, Shirai N, Sugama Y, Ohsawa M, Adachi K, Watanabe K, Nakamura S, Fujiwara Y, Oshitani N, Higuchi K, Maeda K, Hirakawa K, Arakawa T, Ueda M. Close association between activated platelets and neutrophils in the active phase of ulcerative colitis in humans. Inflamm Bowel Dis 2006; 12:727-35. [PMID: 16917228 DOI: 10.1097/00054725-200608000-00009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Neutrophils are considered to play a causative role in inflammatory mucosal injury in ulcerative colitis (UC), and an association between platelets and neutrophils may contribute to the progression of the inflammatory processes. To test this hypothesis, we performed immunohistochemical and flow cytometric analyses on tissue and blood samples from patients with UC. MATERIALS AND METHODS Colonic mucosal tissues of patients with active (n = 27) or inactive (n = 16) UC and normal controls (n = 11) were subjected to immunohistochemical staining for markers of activated platelets (glycoprotein IIb/IIIa and P-selectin) and neutrophils (neutrophil elastase, myeloperoxidase, and CD66b). The amounts of stained cells were evaluated by computer-aided morphometry. Peripheral blood samples from patients (n = 8) and healthy volunteers (n = 8) were subjected to comparative flow cytometric analysis of activated platelets. RESULTS P-selectin-positive activated platelets were frequently aggregated in the inflamed mucosa, especially in ulcerative lesions, and were close to regions of dense neutrophil infiltration. An increase in the number of activated platelets in the colonic lesions was associated with an increase in infiltrating neutrophils and was related to the severity of the disease. The flow cytometric analysis indicated that circulating platelets of patients with UC were highly activated. CONCLUSIONS The present study demonstrated that a close association between activated platelets and neutrophils is a prominent pathological change in both the affected colonic mucosa and peripheral blood of patients with active-phase UC. This suggests that platelet-neutrophil association may play an important role in the progression of inflammatory processes in UC.
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Affiliation(s)
- Soichiro Kayo
- Department of Pathology, Osaka City University Graduate School of Medicine, Osaka, Japan
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Robless P, Okonko D, Mikhailidis DP, Stansby G. Dextran 40 reduces in vitro platelet aggregation in peripheral arterial disease. Platelets 2005; 15:215-22. [PMID: 15203712 DOI: 10.1080/09537100410001682814] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Dextran 40 has been used to prevent post-operative thrombosis. However, its antithrombotic and antiplatelet effects in peripheral arterial disease (PAD) are poorly understood. We studied the in vitro effects of Dextran 40 on platelet function in control subjects and PAD patients using whole blood methods. Platelet function was assessed in 20 control subjects and 20 PAD patients. Spontaneous platelet aggregation (SPA) and agonist-induced platelet aggregation in response to increasing concentrations of Dextran 40 in vitro were measured by whole blood aggregometry. Flow cytometric measurements of platelet P-selectin, GpIIb/IIIa, GpIb and PAC-1 binding were also performed. There was no difference in SPA or ADP-induced aggregation in control patients with Dextran 40 in vitro. However, Dextran 40 inhibited collagen-induced aggregation in control patients (P < 0.05, Friedman test). In PAD patients, SPA and ADP (1 microM)-induced aggregation were significantly reduced by Dextran 40 in vitro (P < 0.001, Friedman test). In PAD patients, collagen-induced platelet aggregation (1 and 5 microg/ml) was significantly reduced by Dextran 40 in vitro (P < 0.01, Friedman test). GpIIb/IIIa, PAC-1 and P-selectin expression were significantly reduced in whole blood samples from PAD patients following incubation with Dextran 40 (P < 0.05, Wilcoxon rank test) but not in samples from control patients. Dextran 40 reduces spontaneous and agonist-induced platelet aggregation as well as the surface expression of markers of platelet activation in PAD patients. This antiplatelet effect may be of benefit to patients undergoing vascular surgical procedures where thrombosis is a significant risk.
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Affiliation(s)
- P Robless
- Regional Vascular Unit, St Mary's Hospital, Praed St, London W2 1NY, UK
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Wang Y, Richter-Landsberg C, Reiser G. Expression of protease-activated receptors (PARs) in OLN-93 oligodendroglial cells and mechanism of PAR-1-induced calcium signaling. Neuroscience 2004; 126:69-82. [PMID: 15145074 DOI: 10.1016/j.neuroscience.2004.03.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2004] [Indexed: 11/30/2022]
Abstract
Protease-activated receptors (PARs) are a group of four members of the superfamily of G protein-coupled receptors that transduce cell signaling by proteolytic activity of extracellular serine proteases, such as thrombin. Possible expression and functions of PARs in oligodendrocytes, the myelin forming cells of the CNS, are still unclear. Here, the oligodendrocyte cell line OLN-93 was used to investigate the signaling of PARs. By reverse transcription-polymerase chain reaction (RT-PCR), immunostaining and Ca(2+) imaging studies, we demonstrate that OLN-93 cells functionally express PAR-1. PAR-3 seems to be expressed without apparent activity, and PAR-2 and PAR-4 cannot be detected. Short-term stimulation of the OLN-93 cells with PAR-1 agonists, such as thrombin, trypsin and PAR-1 activating peptide, dose-dependently induced a transient rise of [Ca(2+)](i). Concentration-effect curves display a sigmoidal concentration dependence. Elevation of [Ca(2+)](i) induced by PAR-1 mainly resulted from Ca(2+) release from intracellular stores. Studies on the effects of pertussis toxin (PTX), phospholipase C antagonist and 2-APB, showed that in OLN-93 cells (i). the calcium signaling cascade from PAR-1 was mediated through PTX-insensitive G proteins, (ii). activation of phospholipase C and liberation of InsP(3) were events upstream of the Ca(2+) release from the stores. In addition, the present study analyzed PAR-1 desensitization caused by exposure to thrombin, trypsin, and PAR-1 activating peptide, elucidated the influence of the protease cathepsin G on PAR-1 activation, and also characterized PAR-1 desensitization. This is the first study, which shows that OLN-93 oligodendrocytes functionally express PAR-1, and identifies the receptor coupling to mobilization of intracellular calcium. Moreover, the expression of PAR-1 was demonstrated by RT-PCR in primary oligodendrocytes from rat brain.
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Affiliation(s)
- Y Wang
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Institut für Neurobiochemie, Leipziger Strasse 44, 39120 Magdeburg, Germany
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35
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Goel MS, Diamond SL. Neutrophil cathepsin G promotes prothrombinase and fibrin formation under flow conditions by activating fibrinogen-adherent platelets. J Biol Chem 2003; 278:9458-63. [PMID: 12524437 DOI: 10.1074/jbc.m211956200] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Human neutrophil proteases cathepsin G and elastase can directly alter platelet function and/or participate in coagulation cascade reactions on the platelet or neutrophil surface to enhance fibrin formation. The clotting of recalcified platelet-free plasma (PFP) or platelet-rich plasma (PRP) supplemented with corn trypsin inhibitor (to shut down contact activation) was studied in well-plates or flow assays. Inhibitors of cathepsin G or elastase significantly delayed the burst time (t(50)) of thrombin generation in neutrophil-supplemented PRP from 49 min to 59 and 77 min, respectively, in well-plate assays as well as reduced neutrophil-promoted fibrin deposition on fibrinogen-adherent platelets under flow conditions. In flow assays, purified cathepsin G was a far more potent activator of platelet-dependent coagulation than elastase. Anti-tissue factor had no effect on neutrophil protease-enhanced thrombin formation in PRP. The addition of cathepsin G (425 nm) or convulxin (10 nm) to PRP dramatically reduced the t(50) of thrombin generation from 53 min to 17 or 23 min, respectively. In contrast, the addition of elastase to PRP left the t(50) unaltered. Whereas perfusion of PFP (gamma(w) = 62.5 s(-1)) over fibrinogen-adherent platelets did not result in fibrin formation until 50 min, massive fibrin could be observed on cathepsin G-treated platelets even at 35 min. Cathepsin G addition to corn trypsin inhibitor-treated PFP produced little thrombin unless anionic phospholipid was present. However, further activation inhibition studies indicated that cathepsin G enhances fibrin deposition under flow conditions by elevating the activation state of fibrinogen-adherent platelets rather than by cleaving coagulation factors.
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Affiliation(s)
- Mukul S Goel
- Institute for Medicine and Engineering, Department of Chemical Engineering, University of Pennsylvania, 1010 Vagelos Research Laboratories, Philadelphia, Pennsylvania 19104, USA
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36
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Yoshida T, Tang SS, Hsiao LL, Jensen RV, Ingelfinger JR, Gullans SR. Global analysis of gene expression in renal ischemia-reperfusion in the mouse. Biochem Biophys Res Commun 2002; 291:787-94. [PMID: 11866434 DOI: 10.1006/bbrc.2002.6535] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ischemia-induced acute renal failure (ARF) is a relatively common disorder with major morbidity and mortality. To study global gene expression during ARF, 6-week-old C57BL/6 male mice underwent 30 min of bilateral renal ischemia followed by reperfusion [I/R] or sham operation. Oligonucleotide microarrays [Affymetrix] with approximately 10,000 genes, 6,643 of which were present in mouse kidney, were used to analyze mRNA expression for up to 4 days following I/R. Fifty-two genes at day 1 and 40 at day 4 were up-regulated more than 4-fold [400%]. Seventy genes at day 1 and 30 genes at day 4 were down-regulated to under 0.25-fold from baseline [25%]. Real-time quantitative RT-PCR confirmed changes in expression for 8 genes of interest. Most of the induced transcripts are involved in cell structure, extracellular matrix, intracellular calcium binding, and cell division/differentiation. Our data identified several novel genes that may be important in renal repair after ischemia.
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Affiliation(s)
- Takumi Yoshida
- Renal Division, Department of Medicine, Brigham and Women's Hospital, Cambridge, Massachusetts 02139 , USA
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37
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Goel MS, Diamond SL. Neutrophil enhancement of fibrin deposition under flow through platelet-dependent and -independent mechanisms. Arterioscler Thromb Vasc Biol 2001; 21:2093-8. [PMID: 11742890 DOI: 10.1161/hq1201.100255] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We examined the effect of adherent neutrophils on fibrin deposition under laminar flow conditions. Perfusion of recalcified citrated platelet-free plasma (PFP) over neutrophils adherent to fibrinogen-coated glass at a venous wall shear rate of 62.5 s(-1) for 15 minutes resulted in dense deposition of fibrin around each neutrophil, whereas fibrin deposition on glass alone was sparse. Fibrin deposition on neutrophils was markedly reduced by anti-CD18 or anti-CD11b or a higher shear rate (250 s(-1)). Significantly less fibrin was deposited around adherent fibrinogen-coated beads, indicating that nonspecific "cross-sectional capture" effects were not responsible for the massive fibrin deposition on neutrophils. Direct visualization of fibrin capture by neutrophils and elimination of fibrin deposition at 15 minutes by a factor XIIa inhibitor (50 microg/mL corn trypsin inhibitor [CTI]) or elastase/cathepsin G inhibitors (Methoxysuccinyl-Ala-Ala-Pro-Ala-Chloromethyl-Ketone/Z-Gly-Leu-Phe-CMK, 100 micromol/L) indicated that neutrophils can capture short fibrin strands flowing in recalcified PFP lacking CTI and can also promote thrombin generation through pathways attenuated by inhibitors of factor XIIa, elastase, and cathepsin G. When neutrophils were allowed to interact with platelets on a fibrinogen surface before perfusion of recalcified CTI-treated PFP, the fibrin deposition was observed to be dramatic compared with that over surfaces coated with platelets alone or neutrophils alone and compared with that formed on platelets adherent to collagen. This neutrophil promotion of platelet-mediated fibrin formation was attenuated by inhibitors of elastase or cathepsin G but not anti-tissue factor antibody. Neutrophils can interact with platelets via released proteases to increase platelet procoagulant activity and fibrin formation in CTI-treated plasma under the low-flow conditions expected in venous thrombosis or inflammation.
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Affiliation(s)
- M S Goel
- Institute for Medicine and Engineering, Department of Chemical Engineering, University of Pennsylvania, Philadelphia 19104, USA
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38
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Gardiner EE, De Luca M, McNally T, Michelson AD, Andrews RK, Berndt MC. Regulation of P-selectin binding to the neutrophil P-selectin counter-receptor P-selectin glycoprotein ligand-1 by neutrophil elastase and cathepsin G. Blood 2001; 98:1440-7. [PMID: 11520793 DOI: 10.1182/blood.v98.5.1440] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the inflammatory response, leukocyte rolling before adhesion and transmigration through the blood vessel wall is mediated by specific cell surface adhesion receptors. Neutrophil rolling involves the interaction of P-selectin expressed on activated endothelium and its counter-receptor on neutrophils, P-selectin glycoprotein ligand-1 (PSGL-1). Here, it is reported that P-selectin binding to neutrophils is lost under conditions that cause the release of proteinases from neutrophil primary granules. Treatment of neutrophils with the purified neutrophil granule proteinases, cathepsin G and elastase, rapidly abolished their capacity to bind P-selectin. This inactivation corresponded to loss of the N-terminal domain of PSGL-1, as assessed by Western blot analysis. A loss of intact PSGL-1 protein from the surfaces of neutrophils after the induction of degranulation was also detected by Western blot analysis. Cathepsin G initially cleaved near the PSGL-1 N-terminus, whereas neutrophil elastase predominantly cleaved at a more C-terminal site within the protein mucin core. Consistent with this, cathepsin G cleaved a synthetic peptide based on the PSGL-1 N-terminus between Tyr-7/Leu-8. Under conditions producing neutrophil degranulation in incubations containing mixtures of platelets and neutrophils, the loss of PSGL-1, but not P-selectin, from platelet-neutrophil lysates was detected. Cathepsin G- or neutrophil elastase-mediated PSGL-1 proteolysis may constitute a potential autocrine mechanism for down-regulation of neutrophil adhesion to P-selectin.
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Affiliation(s)
- E E Gardiner
- Hazel and Pip Appel Vascular Biology Laboratory, Baker Medical Research Institute, Melbourne, Australia
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39
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Herrmann SM, Funke-Kaiser H, Schmidt-Petersen K, Nicaud V, Gautier-Bertrand M, Evans A, Kee F, Arveiler D, Morrison C, Orzechowski HD, Elbaz A, Amarenco P, Cambien F, Paul M. Characterization of polymorphic structure of cathepsin G gene: role in cardiovascular and cerebrovascular diseases. Arterioscler Thromb Vasc Biol 2001; 21:1538-43. [PMID: 11557685 DOI: 10.1161/hq0901.095555] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cathepsin G (CTSG), a serine protease released from activated neutrophils, may cause platelet activation, leading to intravascular thrombosis, thus contributing to cardiovascular and cerebrovascular disease. Applying the candidate gene approach, we screened the 5'-flanking region and the entire coding region of the CTSG gene for genetic variation by using polymerase chain reaction/single-strand conformation polymorphism analysis from 96 patients at high risk for myocardial infarction (MI). We identified 4 polymorphisms in the 5'-flanking region (G-618C, G-315A, C-179T, and C-160T) and 1 polymorphism in the coding region (Asn125Ser) of the gene and genotyped the participants in the Etude Cas-Temoins sur l'Infarctus du Myocarde (ECTIM Study), a case-control study for MI, and in the Etude du Profil Génétique de l'Infarctus Cérébral (GENIC Study), a case-control study for brain infarction (BI), for all identified genetic variants. The potential in vitro functionality of the 4 variants in the 5'-flanking region was investigated with transient transfection analyses in U937 cells with different allelic promoter constructs by using a luciferase assay. Our in vitro analyses did not reveal any differences for the investigated allelic constructs with respect to promoter activity, and none of the polymorphisms in the 5'-flanking region was associated with the available phenotypes in either study. Allele and genotype distributions of all identified polymorphisms did not globally differ between cases and controls in the ECTIM Study. However, in patients from the ECTIM Study, the Ser125 allele was significantly associated with elevated plasma fibrinogen levels (P=0.006), but this effect was not seen in controls (case-control heterogeneity, P=0.04). There was a significant interaction between CTSG Asn125Ser and the beta-fibrinogen gene polymorphism G-455A on plasma fibrinogen levels (P=0.04). In the GENIC Study, the odds ratio for BI associated with CTSG Ser125 carrying was 1.82 (95% CI 1.16 to 2.84, P=0.008) in patients without a history of cardiovascular or cerebrovascular diseases. Our results indicate that the CTSG Ser125 allele is associated with plasma fibrinogen levels in MI patients from the ECTIM Study and with BI in the GENIC Study. Further studies should be carried out to define the underlying mechanisms.
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Affiliation(s)
- S M Herrmann
- Institute of Clinical Pharmacology and Toxicology, Department of Clinical Pharmacology, Benjamin Franklin Medical Center, Freie Universität Berlin, Germany.
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40
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Glusa E, Adam C. Endothelium-dependent relaxation induced by cathepsin G in porcine pulmonary arteries. Br J Pharmacol 2001; 133:422-8. [PMID: 11375259 PMCID: PMC1572797 DOI: 10.1038/sj.bjp.0704089] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Serine proteinases elicit profound cellular effects in various tissues mediated by activation of proteinase-activated receptors (PAR). In the present study, we investigated the vascular effects of cathepsin G, a serine proteinase that is present in the azurophil granules of leukocytes and is known to activate several cells that express PARs. In prostaglandin F2alpha (3 microM)-precontracted rings from porcine pulmonary arteries with intact endothelium, cathepsin G caused concentration-dependent relaxant responses (pEC(50)=9.64+/-0.12). The endothelium-dependent relaxant effect of cathepsin G could also be demonstrated in porcine coronary arteries (pEC(50)=9.23+/-0.07). In pulmonary arteries the cathepsin G-induced relaxation was inhibited after blockade of nitric oxide synthesis by L-NAME (200 microM) and was absent in endothelium-denuded vessels. Bradykinin- and cathepsin G-induced relaxant effects were associated with a 5.7 fold and 2.4 fold increase in the concentration of cyclic GMP, respectively. Compared with thrombin and trypsin, which also produced an endothelium-dependent relaxation in pulmonary arteries, cathepsin G was 2.5 and four times more potent, respectively. Cathepsin G caused only small homologous desensitization. In cathepsin G-challenged vessels, thrombin was still able to elicit a relaxant effect. The effects of cathepsin G were blocked by soybean trypsin inhibitor (IC(50)=0.043 microg ml(-1)), suggesting that proteolytic activity is essential for induction of relaxation. Recombinant acetyl-eglin C proved to be a potent inhibitor (IC(50)=0.14 microg ml(-1)) of the cathepsin G effect, whereas neither indomethacin (3 microM) nor the thrombin inhibitor hirudin (5 ATU ml(-1)) elicited any inhibitory activity. Due to their polyanionic structure defibrotide (IC(50)=0.11 microg ml(-1)), heparin (IC(50)=0.48 microg ml(-1)) and suramin (IC(50)=1.85 microg ml(-1)) diminished significantly the relaxation in response to the basic protein cathepsin G. In conclusion, like thrombin and trypsin, cathepsin G is able to induce endothelium-dependent vascular relaxation. It can be released from activated leukocytes at sites of vascular injury and inflammation and, therefore, sufficiently high concentrations might be reached locally in the vascular space to induce vasodilatation.
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Affiliation(s)
- E Glusa
- Center for Vascular Biology and Medicine, Friedrich-Schiller-University Jena, Nordhäuser Strasse 78, D-99089 Erfurt, Germany.
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41
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Sindram D, Porte RJ, Hoffman MR, Bentley RC, Clavien PA. Synergism between platelets and leukocytes in inducing endothelial cell apoptosis in the cold ischemic rat liver: a Kupffer cell-mediated injury. FASEB J 2001; 15:1230-2. [PMID: 11344097 DOI: 10.1096/fj.00-0554fje] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- D Sindram
- Hepatobiliary and Liver Transplant Laboratory, Department of Surgery, Duke University Medical Center, Durham North Carolina, USA
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42
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Abstract
The four PAR family members are G protein coupled receptors that are normally activated by proteolytic exposure of an occult tethered ligand. Three of the family members are thrombin receptors. The fourth (PAR2) is not activated by thrombin, but can be activated by other proteases, including trypsin, tryptase and Factor Xa. This review focuses on recent information about the manner in which signaling through these receptors is initiated and terminated, including evidence for inter- as well as intramolecular modes of activation, and continuing efforts to identify additional, biologically-relevant proteases that can activate PAR family members.
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Affiliation(s)
- P J O'Brien
- Department of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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43
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Tang Z, Tracy RP. Candidate genes and confirmed genetic polymorphisms associated with cardiovascular diseases: a tabular assessment. J Thromb Thrombolysis 2001; 11:49-81. [PMID: 11248790 DOI: 10.1023/a:1008956327032] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Z Tang
- Laboratory of Clinical Biochemistry Research, Department of Pathology, University of Vermont, Colchester 05446, USA.
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44
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Schramm DD, Wang JF, Holt RR, Ensunsa JL, Gonsalves JL, Lazarus SA, Schmitz HH, German JB, Keen CL. Chocolate procyanidins decrease the leukotriene-prostacyclin ratio in humans and human aortic endothelial cells. Am J Clin Nutr 2001; 73:36-40. [PMID: 11124747 DOI: 10.1093/ajcn/73.1.36] [Citation(s) in RCA: 165] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Polyphenolic phytochemicals inhibit vascular and inflammatory processes that contribute to disease. These effects are hypothesized to result from polyphenol-mediated alterations in cellular eicosanoid synthesis. OBJECTIVE The objective was to determine and compare the ability of cocoa procyanidins to alter eicosanoid synthesis in human subjects and cultured human aortic endothelial cells. DESIGN After an overnight fast, 10 healthy subjects (4 men and 6 women) consumed 37 g low-procyanidin (0.09 mg/g) and high-procyanidin (4.0 mg/g) chocolate; the treatments were separated by 1 wk. The investigation had a randomized, blinded, crossover design. Plasma samples were collected before treatment and 2 and 6 h after treatment. Eicosanoids were quantitated by enzyme immunoassay. Endothelial cells were treated in vitro with procyanidins to determine whether the effects of procyanidin in vivo were associated with procyanidin-induced alterations in endothelial cell eicosanoid synthesis. RESULTS Relative to the effects of the low-procyanidin chocolate, high-procyanidin chocolate induced increases in plasma prostacyclin (32%; P<0.05) and decreases in plasma leukotrienes (29%; P<0.04). After the in vitro procyanidin treatments, aortic endothelial cells synthesized twice as much 6-keto-prostaglandin F(1alpha) (P<0.01) and 16% less leukotriene (P<0.05) as did control cells. The in vitro and in vivo effects of procyanidins on plasma leukotriene-prostacyclin ratios in culture medium were also comparable: decreases of 58% and 52%, respectively. CONCLUSION Data from this short-term investigation support the concept that certain food-derived flavonoids can favorably alter eicosanoid synthesis in humans, providing a plausible hypothesis for a mechanism by which they can decrease platelet activation in humans.
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Affiliation(s)
- D D Schramm
- Department of Nutrition, University of California, Davis 95616-8669, USA.
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45
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Michelson AD, Barnard MR, Krueger LA, Frelinger AL, Furman MI. Evaluation of platelet function by flow cytometry. Methods 2000; 21:259-70. [PMID: 10873480 DOI: 10.1006/meth.2000.1006] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Platelet function in whole blood can be comprehensively evaluated by flow cytometry. Flow cytometry can be used to measure platelet reactivity, circulating activated platelets, platelet-platelet aggregates, leukocyte-platelet aggregates, procoagulant platelet-derived microparticles, and calcium flux. Clinical applications of whole blood flow cytometric assays of platelet function in disease states (e.g., acute coronary syndromes, angioplasty, and stroke) may include identification of patients who would benefit from additional antiplatelet therapy and prediction of ischemic events. Circulating monocyte-platelet aggregates appear to be a more sensitive marker of in vivo platelet activation than circulating P-selectin-positive platelets. Flow cytometry can also be used in the following clinical settings: monitoring of GPIIb-IIIa antagonist therapy, diagnosis of inherited deficiencies of platelet surface glycoproteins, diagnosis of storage pool disease, diagnosis of heparin-induced thrombocytopenia, and measurement of the rate of thrombopoiesis.
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Affiliation(s)
- A D Michelson
- Center for Platelet Function Studies, University of Massachusetts Medical School, Worcester, Massachusetts, 01655, USA
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46
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Hernández MR, Tàssies D, Escolar G, Bozzo J, Ordinas A. A monoclonal antibody to leukocyte integrin CD11b inhibits leukocyte and platelet activation induced by shear stress. Inflammopharmacology 2000. [DOI: 10.1163/15685600038170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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47
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Sambrano GR, Huang W, Faruqi T, Mahrus S, Craik C, Coughlin SR. Cathepsin G activates protease-activated receptor-4 in human platelets. J Biol Chem 2000; 275:6819-23. [PMID: 10702240 DOI: 10.1074/jbc.275.10.6819] [Citation(s) in RCA: 259] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Of the four known protease-activated receptors (PARs), PAR1 and PAR4 are expressed by human platelets and mediate thrombin signaling. Whether these receptors are redundant, interact, or play at least partially distinct roles is unknown. It is possible that PAR1 and/or PAR4 might confer responsiveness to proteases other than thrombin. The neutrophil granule protease, cathepsin G, is known to cause platelet secretion and aggregation. We now report that this action of cathepsin G is mediated by PAR4. Cathepsin G triggered calcium mobilization in PAR4-transfected fibroblasts, PAR4-expressing Xenopus oocytes, and washed human platelets. An antibody raised against the PAR4 thrombin cleavage site blocked platelet activation by cathepsin G but not other agonists. Desensitization with a PAR4 activating peptide had a similar effect. By contrast, inhibition of PAR1 function had no effect on platelet responses to cathepsin G. When neutrophils were present, the neutrophil agonist fMet-Leu-Phe triggered calcium signaling in Fura-2-loaded platelets. Strikingly, this neutrophil-dependent platelet activation was blocked by the PAR4 antibody. These data show that PAR4 mediates platelet responses to cathepsin G and support the hypothesis that cathepsin G might mediate neutrophil-platelet interactions at sites of vascular injury or inflammation.
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Affiliation(s)
- G R Sambrano
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California 94143-0130, USA
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48
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Abstract
Cathepsin G is a neutral serine protease that is highly expressed at the promyelocyte stage of myeloid development. We have developed a homologous recombination strategy to create a loss-of-function mutation for murine cathepsin G. Bone marrow derived from mice homozygous for this mutation had no detectable cathepsin G protein or activity, indicating that no other protease in bone marrow cells has the same specificity. Hematopoiesis in cathepsin G−/− mice is normal, and the mice have no overt abnormalities in blood clotting. Neutrophils derived from cathepsin G−/− mice have normal morphology and azurophil granule composition; these neutrophils also display normal phagocytosis and superoxide production and have normal chemotactic responses to C5a, fMLP, and interleukin-8. Although cathepsin G has previously shown to have broad spectrum antibiotic properties, challenges of mice with Staphylococcus aureus, Klebsiella pneumoniae, or Escherichia coli yielded survivals that were not different from those of wild-type animals. In sum, cathepsin G−/− neutrophils have no obvious defects in function; either cathepsin G is not required for any of these normal neutrophil functions or related azurophil granule proteases with different specificities (ie, neutrophil elastase, proteinase 3, azurocidin, and/or others) can substitute for it in vivo.
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Abstract
AbstractCathepsin G is a neutral serine protease that is highly expressed at the promyelocyte stage of myeloid development. We have developed a homologous recombination strategy to create a loss-of-function mutation for murine cathepsin G. Bone marrow derived from mice homozygous for this mutation had no detectable cathepsin G protein or activity, indicating that no other protease in bone marrow cells has the same specificity. Hematopoiesis in cathepsin G−/− mice is normal, and the mice have no overt abnormalities in blood clotting. Neutrophils derived from cathepsin G−/− mice have normal morphology and azurophil granule composition; these neutrophils also display normal phagocytosis and superoxide production and have normal chemotactic responses to C5a, fMLP, and interleukin-8. Although cathepsin G has previously shown to have broad spectrum antibiotic properties, challenges of mice with Staphylococcus aureus, Klebsiella pneumoniae, or Escherichia coli yielded survivals that were not different from those of wild-type animals. In sum, cathepsin G−/− neutrophils have no obvious defects in function; either cathepsin G is not required for any of these normal neutrophil functions or related azurophil granule proteases with different specificities (ie, neutrophil elastase, proteinase 3, azurocidin, and/or others) can substitute for it in vivo.
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Réhault S, Brillard-Bourdet M, Juliano MA, Juliano L, Gauthier F, Moreau T. New, sensitive fluorogenic substrates for human cathepsin G based on the sequence of serpin-reactive site loops. J Biol Chem 1999; 274:13810-7. [PMID: 10318785 DOI: 10.1074/jbc.274.20.13810] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cathepsin G has both trypsin- and chymotrypsin-like activity, but studies on its enzymatic properties have been limited by a lack of sensitive synthetic substrates. Cathepsin G activity is physiologically controlled by the fast acting serpin inhibitors alpha1-antichymotrypsin and alpha1-proteinase inhibitor, in which the reactive site loops are cleaved during interaction with their target enzymes. We therefore synthesized a series of intramolecularly quenched fluorogenic peptides based on the sequence of various serpin loops. Those peptides were assayed as substrates for cathepsin G and other chymotrypsin-like enzymes including chymotrypsin and chymase. Peptide substrates derived from the alpha1-antichymotrypsin loop were the most sensitive for cathepsin G with kcat/Km values of 5-20 mM-1 s-1. Substitutions were introduced at positions P1 and P2 in alpha1-antichymotrypsin-derived substrates to tentatively improve their sensitivity. Replacement of Leu-Leu in ortho-aminobenzoyl (Abz)-Thr-Leu-Leu-Ser-Ala-Leu-Gln-N-(2, 4-dinitrophenyl)ethylenediamine (EDDnp) by Pro-Phe in Abz-Thr-Pro-Phe-Ser-Ala-Leu-Gln-EDDnp produced the most sensitive substrate of cathepsin G ever reported. It was cleaved with a specificity constant kcat/Km of 150 mM-1 s-1. Analysis by molecular modeling of a peptide substrate bound into the cathepsin G active site revealed that, in addition to the protease S1 subsite, subsites S1' and S2' significantly contribute to the definition of the substrate specificity of cathepsin G.
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Affiliation(s)
- S Réhault
- Laboratory of Enzymology and Protein Chemistry, University François Rabelais, 2bis Boulevard Tonnellé, 37032 Tours Cedex, France
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