1
|
Li X, Song X, Mahmood DFD, Sim MMS, Bidarian SJ, Wood JP. Activated protein C, protein S, and tissue factor pathway inhibitor cooperate to inhibit thrombin activation. Thromb Res 2023; 230:84-93. [PMID: 37660436 PMCID: PMC10543463 DOI: 10.1016/j.thromres.2023.08.012] [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: 04/02/2023] [Revised: 07/20/2023] [Accepted: 08/17/2023] [Indexed: 09/05/2023]
Abstract
INTRODUCTION Thrombin, the enzyme which converts fibrinogen into a fibrin clot, is produced by the prothrombinase complex, composed of factor Xa (FXa) and factor Va (FVa). Down-regulation of this process is critical, as excess thrombin can lead to life-threatening thrombotic events. FXa and FVa are inhibited by the anticoagulants tissue factor pathway inhibitor alpha (TFPIα) and activated protein C (APC), respectively, and their common cofactor protein S (PS). However, prothrombinase is resistant to either of these inhibitory systems in isolation. MATERIALS AND METHODS We hypothesized that these anticoagulants function best together, and tested this hypothesis using purified proteins and plasma-based systems. RESULTS In plasma, TFPIα had greater anticoagulant activity in the presence of APC and PS, maximum PS activity required both TFPIα and APC, and antibodies against TFPI and APC had an additive procoagulant effect, which was mimicked by an antibody against PS alone. In purified protein systems, TFPIα dose-dependently inhibited thrombin activation by prothrombinase, but only in the presence of APC, and this activity was enhanced by PS. Conversely, FXa protected FVa from cleavage by APC, even in the presence of PS, and TFPIα reversed this protection. However, prothrombinase assembled on platelets was still protected from inhibition, even in the presence of TFPIα, APC, and PS. CONCLUSIONS We propose a model of prothrombinase inhibition through combined targeting of both FXa and FVa, and that this mechanism enables down-regulation of thrombin activation outside of a platelet clot. Platelets protect prothrombinase from inhibition, however, supporting a procoagulant environment within the clot.
Collapse
Affiliation(s)
- Xian Li
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States of America
| | - Xiaohong Song
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States of America
| | - Dlovan F D Mahmood
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States of America
| | - Martha M S Sim
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, United States of America
| | - Sara J Bidarian
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States of America
| | - Jeremy P Wood
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, United States of America; Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, United States of America; Division of Cardiovascular Medicine, Gill Heart and Vascular Institute, University of Kentucky, Lexington, KY, United States of America.
| |
Collapse
|
2
|
Lei B, Wang C, Snow K, Graton ME, Tighe RM, Fager AM, Hoffman MR, Giangrande PH, Miller FJ. Inhalation of an RNA aptamer that selectively binds extracellular histones protects from acute lung injury. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 31:662-673. [PMID: 36910716 PMCID: PMC9999168 DOI: 10.1016/j.omtn.2023.02.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 02/15/2023] [Indexed: 03/06/2023]
Abstract
Acute lung injury (ALI) is a syndrome of acute inflammation, barrier disruption, and hypoxemic respiratory failure associated with high morbidity and mortality. Diverse conditions lead to ALI, including inhalation of toxic substances, aspiration of gastric contents, infection, and trauma. A shared mechanism of acute lung injury is cellular toxicity from damage-associated molecular patterns (DAMPs), including extracellular histones. We recently described the selection and efficacy of a histone-binding RNA aptamer (HBA7). The current study aimed to identify the effects of extracellular histones in the lung and determine if HBA7 protected mice from ALI. Histone proteins decreased metabolic activity, induced apoptosis, promoted proinflammatory cytokine production, and caused endothelial dysfunction and platelet activation in vitro. HBA7 prevented these effects. The oropharyngeal aspiration of histone proteins increased neutrophil and albumin levels in bronchoalveolar lavage fluid (BALF) and precipitated neutrophil infiltration, interstitial edema, and barrier disruption in alveoli in mice. Similarly, inhaling wood smoke particulate matter, as a clinically relevant model, increased lung inflammation and alveolar permeability. Treatment by HBA7 alleviated lung injury in both models of ALI. These findings demonstrate the pulmonary delivery of HBA7 as a nucleic acid-based therapeutic for ALI.
Collapse
Affiliation(s)
- Beilei Lei
- Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Chaojian Wang
- Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Kamie Snow
- Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Murilo E Graton
- Department of Medicine, Duke University, Durham, NC 27710, USA.,São Paulo State University, School of Dentistry, Campus of Aracatuba, São Paulo 16015-050, Brazil
| | - Robert M Tighe
- Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Ammon M Fager
- Department of Medicine, Duke University, Durham, NC 27710, USA.,Veterans Affairs Medical Center, Durham, NC 27705, USA
| | - Maureane R Hoffman
- Department of Pathology, Duke University, Durham, NC 27710, USA.,Veterans Affairs Medical Center, Durham, NC 27705, USA
| | | | - Francis J Miller
- Department of Medicine, Duke University, Durham, NC 27710, USA.,Veterans Affairs Tennessee Valley Healthcare, Nashville, TN 37212, USA.,Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37240, USA
| |
Collapse
|
3
|
Slaninova N, Bryjova I, Lasota Z, Richterova R, Kubicek J, Augustynek M, Seal A, Krejcar O, Proto A. Thrombotic and Atherogenetic Predisposition in Polyglobulic Donors. Biomedicines 2022; 10:biomedicines10040888. [PMID: 35453637 PMCID: PMC9027744 DOI: 10.3390/biomedicines10040888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/31/2022] [Accepted: 04/07/2022] [Indexed: 02/04/2023] Open
Abstract
This work analyses the results of research regarding the predisposition of genetic hematological risks associated with secondary polyglobulia. The subjects of the study were selected based on shared laboratory markers and basic clinical symptoms. JAK2 (Janus Kinase 2) mutation negativity represented the common genetic marker of the subjects in the sample of interest. A negative JAK2 mutation hypothetically excluded the presence of an autonomous myeloproliferative disease at the time of detection. The parameters studied in this work focused mainly on thrombotic, immunological, metabolic, and cardiovascular risks. The final goal of the work was to discover the most significant key markers for the diagnosis of high-risk patients and to exclude the less important or only complementary markers, which often represent a superfluous economic burden for healthcare institutions. These research results are applicable as a clinical guideline for the effective diagnosis of selected parameters that demonstrated high sensitivity and specificity. According to the results obtained in the present research, groups with a high incidence of mutations were evaluated as being at higher risk for polycythemia vera disease. It was not possible to clearly determine which of the patients examined had a higher risk of developing the disease as different combinations of mutations could manifest different symptoms of the disease. In general, the entire study group was at risk for manifestations of polycythemia vera disease without a clear diagnosis. The group with less than 20% incidence appeared to be clinically insignificant for polycythemia vera testing and thus there is a potential for saving money in mutation testing. On the other hand, the JAK V617F (somatic mutation of JAK2) parameter from this group should be investigated as it is a clear exclusion or confirmation of polycythemia vera as the primary disease.
Collapse
Affiliation(s)
- Nikola Slaninova
- Department of Cybernetics and Biomedical Engineering, VŠB—Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava–Poruba, Czech Republic; (N.S.); (I.B.); (M.A.); (A.P.)
| | - Iveta Bryjova
- Department of Cybernetics and Biomedical Engineering, VŠB—Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava–Poruba, Czech Republic; (N.S.); (I.B.); (M.A.); (A.P.)
| | - Zenon Lasota
- Blood Donor Center, tr. T. G. Masaryka 495, 738 01 Frydek-Mistek, Czech Republic; (Z.L.); (R.R.)
| | - Radmila Richterova
- Blood Donor Center, tr. T. G. Masaryka 495, 738 01 Frydek-Mistek, Czech Republic; (Z.L.); (R.R.)
| | - Jan Kubicek
- Department of Cybernetics and Biomedical Engineering, VŠB—Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava–Poruba, Czech Republic; (N.S.); (I.B.); (M.A.); (A.P.)
- Correspondence:
| | - Martin Augustynek
- Department of Cybernetics and Biomedical Engineering, VŠB—Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava–Poruba, Czech Republic; (N.S.); (I.B.); (M.A.); (A.P.)
| | - Ayan Seal
- Department of Computer Science & Engineering, PDPM Indian Institute of Information Technology, Design and Manufacturing, Jabalpur 482005, India;
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Hradecka 1249, 500 03 Hradec Kralove, Czech Republic;
| | - Ondrej Krejcar
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Hradecka 1249, 500 03 Hradec Kralove, Czech Republic;
| | - Antonino Proto
- Department of Cybernetics and Biomedical Engineering, VŠB—Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava–Poruba, Czech Republic; (N.S.); (I.B.); (M.A.); (A.P.)
| |
Collapse
|
4
|
Stacey D, Chen L, Stanczyk PJ, Howson JMM, Mason AM, Burgess S, MacDonald S, Langdown J, McKinney H, Downes K, Farahi N, Peters JE, Basu S, Pankow JS, Tang W, Pankratz N, Sabater-Lleal M, de Vries PS, Smith NL, Gelinas AD, Schneider DJ, Janjic N, Samani NJ, Ye S, Summers C, Chilvers ER, Danesh J, Paul DS. Elucidating mechanisms of genetic cross-disease associations at the PROCR vascular disease locus. Nat Commun 2022; 13:1222. [PMID: 35264566 PMCID: PMC8907312 DOI: 10.1038/s41467-022-28729-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 02/08/2022] [Indexed: 02/05/2023] Open
Abstract
Many individual genetic risk loci have been associated with multiple common human diseases. However, the molecular basis of this pleiotropy often remains unclear. We present an integrative approach to reveal the molecular mechanism underlying the PROCR locus, associated with lower coronary artery disease (CAD) risk but higher venous thromboembolism (VTE) risk. We identify PROCR-p.Ser219Gly as the likely causal variant at the locus and protein C as a causal factor. Using genetic analyses, human recall-by-genotype and in vitro experimentation, we demonstrate that PROCR-219Gly increases plasma levels of (activated) protein C through endothelial protein C receptor (EPCR) ectodomain shedding in endothelial cells, attenuating leukocyte-endothelial cell adhesion and vascular inflammation. We also associate PROCR-219Gly with an increased pro-thrombotic state via coagulation factor VII, a ligand of EPCR. Our study, which links PROCR-219Gly to CAD through anti-inflammatory mechanisms and to VTE through pro-thrombotic mechanisms, provides a framework to reveal the mechanisms underlying similar cross-phenotype associations.
Collapse
Affiliation(s)
- David Stacey
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Lingyan Chen
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Paulina J Stanczyk
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Joanna M M Howson
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Department of Genetics, Novo Nordisk Research Centre Oxford, Innovation Building, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Amy M Mason
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Stephen Burgess
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge, UK
| | - Stephen MacDonald
- Specialist Haemostasis Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Jonathan Langdown
- Specialist Haemostasis Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Harriett McKinney
- Department of Haematology, University of Cambridge, Cambridge, UK
- National Health Service Blood and Transplant, Cambridge, UK
| | - Kate Downes
- Department of Haematology, University of Cambridge, Cambridge, UK
- National Health Service Blood and Transplant, Cambridge, UK
- National Institute for Health Research BioResource, University of Cambridge, Cambridge, UK
| | - Neda Farahi
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - James E Peters
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London, London, UK
- Health Data Research UK London, London, UK
| | - Saonli Basu
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, USA
| | - James S Pankow
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA
| | - Weihong Tang
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA
| | - Nathan Pankratz
- Department of Laboratory Medicine and Pathology, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Maria Sabater-Lleal
- Genomics of Complex Diseases Group, Sant Pau Biomedical Research Institute, IIB-Sant Pau, Barcelona, Spain
- Cardiovascular Medicine Unit, Department of Medicine, Karolinska Institutet, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Paul S de Vries
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences; School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Nicholas L Smith
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
- Seattle Epidemiologic Research and Information Center, Department of Veterans Affairs Office of Research and Development, Seattle, WA, USA
- Kaiser Permanente Washington Health Research Institute, Seattle, WA, USA
| | | | | | | | - Nilesh J Samani
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | - Shu Ye
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, UK
| | | | - Edwin R Chilvers
- National Heart and Lung Institute, Imperial College London, London, UK
| | - John Danesh
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK
- Department of Human Genetics, Wellcome Sanger Institute, Hinxton, UK
| | - Dirk S Paul
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK.
- Department of Human Genetics, Wellcome Sanger Institute, Hinxton, UK.
| |
Collapse
|
5
|
Østerud B. Commentary on "Therapeutic doses of recombinant factor VIIa in hemophilia generates thrombin in platelet-dependent and -independent mechanisms". J Thromb Haemost 2020; 18:1853-1854. [PMID: 32749057 DOI: 10.1111/jth.14877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 04/23/2020] [Accepted: 04/27/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Bjarne Østerud
- K.G. Jebsen Thrombosis Research and Expertise Center (TREC), UiT The Arctic University of Norway, Tromsø, Norway
| |
Collapse
|
6
|
Keshava S, Pendurthi UR, Esmon CT, Rao LVM. Therapeutic doses of recombinant factor VIIa in hemophilia generates thrombin in platelet-dependent and -independent mechanisms. J Thromb Haemost 2020; 18:1911-1921. [PMID: 32359012 PMCID: PMC7415704 DOI: 10.1111/jth.14881] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND In hemophilia bypass therapy, a platelet-dependent mechanism is believed to be primarily responsible for recombinant factor VIIa (rFVIIa)'s hemostatic effect. rFVIIa may also possibly interact with other cells through its binding to endothelial cell protein C receptor (EPCR) or cell surface phospholipids. OBJECTIVES We aim to investigate the relative contribution of platelet-dependent and platelet-independent mechanisms in rFVIIa-mediated thrombin generation in hemophilic conditions at the injury site. METHODS Platelets were depleted in acquired and genetic hemophilia mice using anti-platelet antibodies. The mice were subjected to the saphenous vein injury, and the hemostatic effect of pharmacological concentrations of rFVIIa was evaluated by measuring thrombin generation at the injury site. RESULTS Administration of anti-mouse CD42 antibodies to mice depleted platelets by more than 95%. As expected, hemophilia mice, compared with wild-type mice, generated only a small fraction of thrombin at the injury site. The depletion of platelets in hemophilia mice further reduced thrombin generation. However, when pharmacological doses of rFVIIa were administered to hemophilia mice, substantial amounts of thrombin were generated even in the platelet-depleted hemophilia mice. No differences in thrombin generation were detected among FVIII-/- , EPCR-deficient FVIII-/- , and EPCR-overexpressing FVIII-/- mice depleted of platelets or not. Evaluation of platelets by flow cytometry as well as immunoblot analysis showed no detectable expression of EPCR. CONCLUSIONS Our data suggest that pharmacological concentrations of rFVIIa generate thrombin in hemophilia in both platelet-dependent and platelet-independent mechanisms.
Collapse
Affiliation(s)
- Shiva Keshava
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Texas, USA
| | - Usha R Pendurthi
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Texas, USA
| | - Charles T. Esmon
- Coagulation Biology Laboratory, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - L. Vijaya Mohan Rao
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Texas, USA
| |
Collapse
|
7
|
Enoksson M, Martin EJ, Holmberg H, Jensen MS, Kjelgaard-Hansen M, Egebjerg T, Buchardt J, Krogh TN, Demuth H, Sanfridson A, Hilden I, Kjalke M, Brophy DF. Enhanced potency of recombinant factor VIIa with increased affinity to activated platelets. J Thromb Haemost 2020; 18:104-113. [PMID: 31549480 DOI: 10.1111/jth.14644] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 09/09/2019] [Accepted: 09/19/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Recombinant factor VIIa (rFVIIa) enhances thrombin generation in a platelet-dependent manner; however, rFVIIa binds activated platelets with relatively low affinity. Triggering receptor expressed on myeloid cells (TREM)-like transcript (TLT)-1 is expressed exclusively on activated platelets. OBJECTIVE To enhance the potency of rFVIIa via binding TLT-1. METHODS Recombinant FVIIa was conjugated to a TLT-1 binding Fab. In vitro potency of this platelet-targeted rFVIIa (PT-rFVIIa) was evaluated using factor X activation assays and by measuring viscoelastic changes in whole blood. In vivo potency was evaluated using a tail vein transection model in F8-/- mice expressing human TLT-1. RESULTS PT-rFVIIa and rFVIIa had similar dissociation constant values for tissue factor binding and similar tissue factor-dependent factor X activation. However, PT-rFVIIa had increased catalytic efficiency on TLT-1-loaded vesicles and activated platelets. The in vitro potency in normal human blood with antibody-induced hemophilia A was dependent on assay conditions used; with maximally activated platelets, the half maximal effective concentration for clot time for PT-rFVIIa was 49-fold lower compared with rFVIIa. In the murine bleeding model, a 53-fold lower half maximal effective concentration was observed for blood loss for PT-rFVIIa, supporting the relevance of the assay conditions with maximally activated platelets. In vitro analysis of blood from subjects with hemophilia A confirmed the data obtained with normal blood. CONCLUSIONS Increasing the affinity of rFVIIa to activated platelets resulted in approximately 50-fold increased potency both in vitro and in the mouse model. The correlation of in vivo with in vitro data using maximally activated platelets supports that these assay conditions are relevant when evaluating platelet-targeted hemostatic concepts.
Collapse
Affiliation(s)
| | - Erika J Martin
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA, USA
| | | | | | | | | | | | | | | | | | | | | | - Donald F Brophy
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA, USA
| |
Collapse
|
8
|
Persson E, Winther M. Limited factor VIIa surface localization requirement of the factor VIIa-induced overall thrombin generation in platelet-rich hemophilia A plasma. Res Pract Thromb Haemost 2019; 3:713-717. [PMID: 31624791 PMCID: PMC6781916 DOI: 10.1002/rth2.12236] [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: 03/27/2019] [Revised: 04/27/2019] [Accepted: 05/27/2019] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Thrombin generation assay (TGA) and thrombelastography (TEG) are increasingly employed, global, in vitro methods for assessment of the procoagulant potential of plasma/blood and possibly ideally suited tools to monitor, for example, therapy with recombinant factor VIIa (FVIIa). It remains controversial to what extent results obtained with spiked and postinfusion samples reflect the outcome in patients. OBJECTIVE To characterize the TGA response to FVIIa in hemophilic plasma and compare with TEG data. METHODS Hemophilia A (HA) was induced in platelet-rich plasma (PRP) from healthy volunteers, followed by spiking with FVIIa, γ-carboxyglutamic acid (Gla)-domainless FVIIa or V158D/E296V/M298Q-FVIIa (FVIIaDVQ). Samples were triggered with tissue factor and analyzed by TGA and TEG in parallel. RESULTS Addition of 25 nmol L-1 FVIIa to HA PRP normalized TEG parameters angle and R time, as well as TGA lag time, but had poor effects on the thrombin peak height and velocity index. All parameters (at least) returned to normal levels either upon adding a much higher concentration of FVIIa (~1500 nmol L-1) or by using the superactive variant FVIIaDVQ. Surprisingly, Gla-domainless derivatives of FVIIa and FVIIaDVQ also yielded considerable effects in HA PRP. CONCLUSIONS The good general responses to clinically effective concentrations of FVIIa (25 and 75 nmol L-1) seen in TEG analyses, as well as for TGA lag time, were accompanied by far-from-normal thrombin peaks. A near-normal thrombin peak response required the presence of considerably higher FVIIa activity but, intriguingly, relied only marginally on a functional Gla domain (ie, on platelet surface localization).
Collapse
Affiliation(s)
- Egon Persson
- Haemophilia ResearchNovo Nordisk A/SMåløvDenmark
| | | |
Collapse
|
9
|
Endothelial Protein C Receptor (EPCR), Protease Activated Receptor-1 (PAR-1) and Their Interplay in Cancer Growth and Metastatic Dissemination. Cancers (Basel) 2019; 11:cancers11010051. [PMID: 30626007 PMCID: PMC6356956 DOI: 10.3390/cancers11010051] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 12/28/2018] [Accepted: 12/28/2018] [Indexed: 12/20/2022] Open
Abstract
Endothelial protein C receptor (EPCR) and protease activated receptor 1 (PAR-1) by themselves play important role in cancer growth and dissemination. Moreover, interactions between the two receptors are essential for tumor progression. EPCR is a cell surface transmembrane glycoprotein localized predominantly on endothelial cells (ECs). It is a vital component of the activated protein C (APC)—mediated anticoagulant and cytoprotective signaling cascade. PAR-1, which belongs to a family of G protein–coupled cell surface receptors, is also widely distributed on endothelial and blood cells, where it plays a critical role in hemostasis. Both EPCR and PAR-1, generally considered coagulation-related receptors, are implicated in carcinogenesis and dissemination of diverse tumor types, and their expression correlates with clinical outcome of cancer patients. Existing data explain some mechanisms by which EPCR/PAR-1 affects cancer growth and metastasis; however, the exact molecular basis of cancer invasion associated with the signaling is still obscure. Here, we discuss the role of EPCR and PAR-1 reciprocal interactions in cancer progression as well as potential therapeutic options targeted specifically to interact with EPCR/PAR-1-induced signaling in cancer patients.
Collapse
|
10
|
Gu SX, Lentz SR. Targeting platelet EPCR for better therapeutic factor VIIa activity. J Thromb Haemost 2018; 16:1814-1816. [PMID: 29982998 PMCID: PMC6156984 DOI: 10.1111/jth.14231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Indexed: 11/30/2022]
Affiliation(s)
- S X Gu
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - S R Lentz
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| |
Collapse
|