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Zheng XL. Mechanism underlying severe deficiency of plasma ADAMTS-13 activity in immune thrombotic thrombocytopenic purpura. J Thromb Haemost 2024; 22:1358-1365. [PMID: 38360215 PMCID: PMC11055658 DOI: 10.1016/j.jtha.2024.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
BACKGROUND Immune-mediated thrombotic thrombocytopenic purpura is caused by autoantibodies against ADAMTS-13, a plasma enzyme that cleaves von Willebrand factor. However, the mechanism resulting in severe deficiency of plasma ADAMTS-13 activity remains controversial. OBJECTIVES To determine the mechanism of autoantibody-mediated severe deficiency of plasma ADAMTS13 activity in immune-mediated thrombotic thrombocytopenic purpura. METHODS Fluorescence resonance energy transfer-VWF73 was used to determine plasma ADAMTS-13 activity. Enzyme-linked immunosorbent assay (ELISA) was used to determine anti-ADAMTS-13 immunoglobulin G. ELISA and capillary electrophoresis-based Western blotting were employed to assess plasma ADAMTS-13 antigen. RESULTS We showed that plasma ADAMTS-13 antigen levels varied substantially in the samples collected on admission despite all showing plasma ADAMTS-13 activity of <10 IU/dL (or <10% of normal level) using either ELISA or Western blotting. More severe deficiency of plasma ADAMTS-13 antigen (<10%) was detected in admission samples by ELISA than by capillary Western blotting. There was a significant but moderate correlation between plasma ADAMTS-13 activity and ADAMTS-13 antigen by either assay method, suggesting that severe deficiency of plasma ADAMTS-13 activity is not entirely associated with low levels of ADAMTS-13 antigen. CONCLUSION We conclude that severe deficiency of plasma ADAMTS-13 activity primarily resulted from antibody-mediated inhibition, but the accelerated clearance of plasma ADAMTS-13 antigen via immune complexes may also contribute significantly to severe deficiency of plasma ADAMTS-13 activity in a subset of patients with acute immune-mediated thrombotic thrombocytopenic purpura.
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Affiliation(s)
- X Long Zheng
- (1)Department of Pathology and Laboratory Medicine, the University of Kansas Medical Center, Kansas City, Kansas, USA; (2)Institue of Reproductive Medicine and Developmental Sciences, the University of Kansas Medical Center, Kansas City, Kansas, USA.
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De Waele L, Sakai K, Mancini I, Sinkovits G, Falter T, Inoue T, Agosti P, Rossmann H, Von Auer C, Tersteeg C, De Meyer SF, Joly BS, Veyradier A, Coppo P, Fijnheer R, Peyvandi F, Prohászka Z, Lämmle B, Vanhoorelbeke K. Open ADAMTS-13 conformation index predicts earlier relapse in immune-mediated thrombotic thrombocytopenic purpura. J Thromb Haemost 2024; 22:493-502. [PMID: 37866519 DOI: 10.1016/j.jtha.2023.10.014] [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: 06/13/2023] [Revised: 09/27/2023] [Accepted: 10/11/2023] [Indexed: 10/24/2023]
Abstract
BACKGROUND ADAMTS-13 adopts an open conformation in patients with immune-mediated thrombotic thrombocytopenic purpura (iTTP) in acute phase while being closed in healthy donors. We reported that a substantial number of patients with iTTP in remission with restored ADAMTS-13 activity (>50%) still had an open ADAMTS-13 conformation, although a closed conformation is expected given the extent of remission. OBJECTIVES To investigate whether open ADAMTS-13, represented by a conformation index >0.5, is associated with a risk of earlier ADAMTS-13 and/or clinical relapse. METHODS We collected follow-up data (ADAMTS-13 parameters, ADAMTS-13 and clinical relapse, and treatment) from 81 patients with iTTP in remission with ADAMTS-13 activity >50%. RESULTS During follow-up, 19 ADAMTS-13 and 10 clinical relapses were reported (median follow-up period, 20 months). First, open or closed ADAMTS-13 conformation was dichotomized based on the 0.5 conformation index cutoff. Open ADAMTS-13 (conformation index, >0.5) was not identified as a risk factor for ADAMTS-13 and clinical relapse (log-rank test and Cox regression model). In contrast, by identifying the optimal conformation index cutoff for relapse prediction, using classification and regression tree analysis, a conformation index >0.645 and >0.835 was shown to be a risk factor for ADAMTS-13 relapse (hazard ratio, 3.3; 95% CI, 1.3-8.3; P = .01) and clinical relapse (hazard ratio, 4.4; 95% CI, 1.3-15.3; P = .02), respectively. CONCLUSION Patients with open ADAMTS-13 with a conformation index >0.645 and >0.835 have a >3- and >4-fold higher risk of earlier ADAMTS-13 and clinical relapse, respectively. Hence, ADAMTS-13 conformation index could be used to complement ADAMTS-13 activity monitoring to timely notice ADAMTS-13 relapse and prevent clinical relapse.
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Affiliation(s)
- Laure De Waele
- Laboratory for Thrombosis Research, Interdisciplinary Research Facility Life Sciences, Katholieke Universiteit Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Kazuya Sakai
- Laboratory for Thrombosis Research, Interdisciplinary Research Facility Life Sciences, Katholieke Universiteit Leuven Campus Kulak Kortrijk, Kortrijk, Belgium; Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
| | - Ilaria Mancini
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Università degli Studi di Milano, Department of Pathophysiology and Transplantation, and Fondazione Luigi Villa, Milan, Italy
| | - György Sinkovits
- Department of Internal Medicine and Hematology, Semmelweis University and Research Group for Immunology and Haematology, Semmelweis University - Eötvös Loránd Research Network (Office for Supported Research Groups), Budapest, Hungary
| | - Tanja Falter
- Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, Mainz, Germany; Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Takashi Inoue
- Department of Evidence-Based Medicine, Nara Medical University, Kashihara, Japan
| | - Pasquale Agosti
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Università degli Studi di Milano, Department of Pathophysiology and Transplantation, and Fondazione Luigi Villa, Milan, Italy
| | - Heidi Rossmann
- Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, Mainz, Germany; Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Charis Von Auer
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany; Department of Hematology, Oncology and Pneumology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Claudia Tersteeg
- Laboratory for Thrombosis Research, Interdisciplinary Research Facility Life Sciences, Katholieke Universiteit Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, Interdisciplinary Research Facility Life Sciences, Katholieke Universiteit Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Bérangère S Joly
- Service d'Hématologie Biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut de Recherche Saint Louis, Université de Paris, Paris, France
| | - Agnès Veyradier
- Service d'Hématologie Biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut de Recherche Saint Louis, Université de Paris, Paris, France
| | - Paul Coppo
- Centre de Référence des Microangiopathies Thrombotiques, Service d'hématologie, Hôpital Saint Antoine, Assistance Publique-Hôpitaux de Paris and Sorbonne Université, Paris, France
| | - Rob Fijnheer
- Department for Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Flora Peyvandi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Università degli Studi di Milano, Department of Pathophysiology and Transplantation, and Fondazione Luigi Villa, Milan, Italy
| | - Zoltán Prohászka
- Department of Internal Medicine and Hematology, Semmelweis University and Research Group for Immunology and Haematology, Semmelweis University - Eötvös Loránd Research Network (Office for Supported Research Groups), Budapest, Hungary
| | - Bernhard Lämmle
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany; Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; Haemostasis Research Unit, University College London, London, United Kingdom
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, Interdisciplinary Research Facility Life Sciences, Katholieke Universiteit Leuven Campus Kulak Kortrijk, Kortrijk, Belgium.
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Halkidis K, Meng C, Liu S, Mayne L, Siegel DL, Zheng XL. Mechanisms of inhibition of human monoclonal antibodies in immune thrombotic thrombocytopenic purpura. Blood 2023; 141:2993-3005. [PMID: 37023370 PMCID: PMC10315623 DOI: 10.1182/blood.2022019252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/17/2023] [Accepted: 03/12/2023] [Indexed: 04/08/2023] Open
Abstract
Antibody binding to a plasma metalloprotease, a disintegrin and metalloproteinase with thrombospondin type 1 repeats 13 (ADAMTS13), is necessary for the development of immune thrombotic thrombocytopenic purpura (iTTP). Inhibition of ADAMTS13-mediated von Willebrand factor (VWF) cleavage by such antibodies clearly plays a role in the pathophysiology of the disease, although the mechanisms by which they inhibit ADAMTS13 enzymatic function are not fully understood. At least some immunoglobulin G-type antibodies appear to affect the conformational accessibility of ADAMTS13 domains involved in both substrate recognition and inhibitory antibody binding. We used single-chain fragments of the variable region previously identified via phage display from patients with iTTP to explore the mechanisms of action of inhibitory human monoclonal antibodies. Using recombinant full-length ADAMTS13, truncated ADAMTS13 variants, and native ADAMTS13 in normal human plasma, we found that, regardless of the conditions tested, all 3 inhibitory monoclonal antibodies tested affected enzyme turnover rate much more than substrate recognition of VWF. Hydrogen-to-deuterium exchange plus mass spectrometry experiments with each of these inhibitory antibodies demonstrated that residues in the active site of the catalytic domain of ADAMTS13 are differentially exposed to solvent in the presence and absence of monoclonal antibody binding. These results support the hypothesis that inhibition of ADAMTS13 in iTTP may not necessarily occur because the antibodies directly prevent VWF binding, but instead because of allosteric effects that impair VWF cleavage, likely by affecting the conformation of the catalytic center in the protease domain of ADAMTS13. Our findings provide novel insight into the mechanism of autoantibody-mediated inhibition of ADAMTS13 and pathogenesis of iTTP.
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Affiliation(s)
- Konstantine Halkidis
- Division of Hematologic Malignancies and Cellular Therapeutics, Department of Internal Medicine, The University of Kansas Medical Center, Kansas City, KS
| | - Chan Meng
- Division of Hematologic Malignancies and Cellular Therapeutics, Department of Internal Medicine, The University of Kansas Medical Center, Kansas City, KS
| | - Szumam Liu
- Department of Pathology and Laboratory Medicine, The University of Kansas Medical Center, Kansas City, KS
| | - Leland Mayne
- Department of Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA
| | - Don L. Siegel
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
| | - X. Long Zheng
- Department of Pathology and Laboratory Medicine, The University of Kansas Medical Center, Kansas City, KS
- Institute of Reproductive Medicine and Developmental Sciences, The University of Kansas Medical Center, Kansas City, KS
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4
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DeYoung V, Singh K, Kretz CA. Mechanisms of ADAMTS13 regulation. J Thromb Haemost 2022; 20:2722-2732. [PMID: 36074019 PMCID: PMC9826392 DOI: 10.1111/jth.15873] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 07/29/2022] [Accepted: 09/06/2022] [Indexed: 01/13/2023]
Abstract
Recombinant ADAMTS13 is currently undergoing clinical trials as a treatment for hereditary thrombotic thrombocytopenic purpura, a lethal microvascular condition resulting from ADAMTS13 deficiency. Preclinical studies have also demonstrated its efficacy in treating arterial thrombosis and inflammation without causing bleeding, suggesting that recombinant ADAMTS13 may have broad applicability as an antithrombotic agent. Despite this progress, we currently do not understand the mechanisms that regulate ADAMTS13 activity in vivo. ADAMTS13 evades canonical means of protease regulation because it is secreted as an active enzyme and has a long half-life in circulation, suggesting that it is not inhibited by natural protease inhibitors. Although shear can spatially and temporally activate von Willebrand factor to capture circulating platelets, it is also required for cleavage by ADAMTS13. Therefore, spatial and temporal regulation of ADAMTS13 activity may be required to stabilize von Willebrand factor-platelet strings at sites of vascular injury. This review outlines potential mechanisms that regulate ADAMTS13 in vivo including shear-dependency, local inactivation, and biochemical and structural regulation of substrate binding. Recently published structural data of ADAMTS13 is discussed, which may help to generate novel hypotheses for future research.
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Affiliation(s)
- Veronica DeYoung
- Department of Medicine, McMaster UniversityThrombosis and Atherosclerosis Research InstituteHamiltonOntarioCanada
| | - Kanwal Singh
- Department of Medicine, McMaster UniversityThrombosis and Atherosclerosis Research InstituteHamiltonOntarioCanada
| | - Colin A. Kretz
- Department of Medicine, McMaster UniversityThrombosis and Atherosclerosis Research InstituteHamiltonOntarioCanada
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Halkidis K, Zheng XL. ADAMTS13 conformations and mechanism of inhibition in immune thrombotic thrombocytopenic purpura. J Thromb Haemost 2022; 20:2197-2203. [PMID: 35842925 PMCID: PMC9587499 DOI: 10.1111/jth.15822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/29/2022] [Accepted: 07/15/2022] [Indexed: 08/31/2023]
Abstract
ADAMTS13, a plasma metalloprotease that cleaves von Willebrand factor, is crucial for normal hemostasis. Acquired autoantibody-mediated deficiency of plasma ADAMTS13 results in a potentially fatal blood disorder, immune thrombotic thrombocytopenic purpura (iTTP). Plasma ADAMTS13 protease appears to exist in multiple conformations. Under physiological conditions, plasma ADAMTS13 exists predominantly in its "closed" conformation (or latent form), which may be activated by lowering pH, ligand binding, and binding of an antibody against the distal domains of ADAMTS13. In patients with iTTP, polyclonal antibodies target at various domains of ADAMTS13. However, nearly all inhibitory antibodies bind the spacer domain, whereas antibodies that bind the distal C-terminal domains may activate ADAMTS13 through removing its allosteric inhibition. Additionally, the anti-C-terminal antibodies may alter the potency of inhibitory antibodies towards ADAMTS13 activity. This review summarizes some of the most recent knowledge about the ADAMTS13 conformation and its mechanism of inhibition by its autoantibodies.
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Affiliation(s)
- Konstantine Halkidis
- Division of Hematologic Malignancies and Cellular Therapeutics, Department of Internal Medicine, The University of Kansas Medical Center, Kansas City, Kansas, USA
| | - X. Long Zheng
- Department of Pathology and Laboratory Medicine, The University of Kansas Medical Center, Kansas City, Kansas, USA
- Institute of Reproductive and Developmental Sciences, The University of Kansas Medical Center, Kansas City, Kansas, USA
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Laghmouchi A, Graça NAG, Voorberg J. Emerging Concepts in Immune Thrombotic Thrombocytopenic Purpura. Front Immunol 2021; 12:757192. [PMID: 34858410 PMCID: PMC8631936 DOI: 10.3389/fimmu.2021.757192] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/27/2021] [Indexed: 12/23/2022] Open
Abstract
Immune thrombotic thrombocytopenic purpura (iTTP) is an autoimmune disorder of which the etiology is not fully understood. Autoantibodies targeting ADAMTS13 in iTTP patients have extensively been studied, the immunological mechanisms leading to the breach of tolerance remain to be uncovered. This review addresses the current knowledge on genetic factors associated with the development of iTTP and the interplay between the patient’s immune system and environmental factors in the induction of autoimmunity against ADAMTS13. HLA-DRB1*11 has been identified as a risk factor for iTTP in the Caucasian population. Interestingly, HLA-DRB1*08:03 was recently identified as a risk factor in the Japanese population. Combined in vitro and in silico MHC class II peptide presentation approaches suggest that an ADAMTS13-derived peptide may bind to both HLA-DRB1*11 and HLA-DRB1*08:03 through different anchor-residues. It is apparent that iTTP is associated with the presence of infectious microorganisms, viruses being the most widely associated with development of iTTP. Infections may potentially lead to loss of tolerance resulting in the shift from immune homeostasis to autoimmunity. In the model we propose in this review, infections disrupt the epithelial barriers in the gut or lung, promoting exposure of antigen presenting cells in the mucosa-associated lymphoid tissue to the microorganisms. This may result in breach of tolerance through the presentation of microorganism-derived peptides that are homologous to ADAMTS13 on risk alleles for iTTP.
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Affiliation(s)
- Aicha Laghmouchi
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
| | - Nuno A G Graça
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
| | - Jan Voorberg
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
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Szóstek-Mioduchowska A, Kordowitzki P. Shedding Light on the Possible Link between ADAMTS13 and Vaccine-Induced Thrombotic Thrombocytopenia. Cells 2021; 10:cells10102785. [PMID: 34685765 PMCID: PMC8535032 DOI: 10.3390/cells10102785] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 12/26/2022] Open
Abstract
Several recent reports have highlighted the onset of vaccine-induced thrombotic thrombocytopaenia (VITT) in some recipients (approximately 1 case out of 100k exposures) of the ChAdOx1 nCoV-19 vaccine (AstraZeneca). Although the underlying events leading to this blood-clotting phenomenon has yet to be elucidated, several critical observations present a compelling potential mechanism. Thrombus formation requires the von Willebrand (VWF) protein to be in ultra-large multimeric state. The conservation of this state is controlled by the ADAMTS13 enzyme, whose proteolytic activity reduces the size of VWF multimers, keeping blood clotting at bay. However, ADAMTS13 cannot act on VWF that is bound to platelet factor 4 (PF4). As such, it is of particular interest to note that a common feature between subjects presenting with VITT is high titres of antibodies against PF4. This raises the possibility that these antibodies preserve the stability of ultra-large VWF complexes, leading to the formation of endothelium-anchored VWF strings, which are capable of recruiting circulating platelets and causing uncontrolled thrombosis in terminal capillaries. Here, we share our viewpoint about the current understanding of the VITT pathogenesis involving the prevention of ADAMTS13's activity on VWF by PF4 antibody-mediated stabilisation/ protection of the PF4-VWF complex.
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Affiliation(s)
- Anna Szóstek-Mioduchowska
- Department for Immunology and Pathology, Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Tuwima Street 10, 10-243 Olsztyn, Poland;
| | - Paweł Kordowitzki
- Department for Immunology and Pathology, Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Tuwima Street 10, 10-243 Olsztyn, Poland;
- Faculty of Biology and Veterinary Medicine, Nicolaus Copernicus University, Gagarina Street 1, 87-100 Torun, Poland
- Correspondence: ; Tel.: +48-89-539-31-28
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Yang J, Wu Z, Xie X, Liu G, Fang Y, Wu J, Lin J. Characterization of the interactions of ADAMTS13 CUB1 domain to WT- and GOF-Spacer domain by molecular dynamics simulation. J Mol Graph Model 2021; 109:108029. [PMID: 34517169 DOI: 10.1016/j.jmgm.2021.108029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/22/2021] [Accepted: 09/05/2021] [Indexed: 10/20/2022]
Abstract
Metalloprotease ADAMTS13 specifically cleaves VWF (von Willebrand Factor) to prevent excessive platelet aggregation and thrombus formation at the sites of vascular injury. To avoid non-specific cleavage, ADAMTS13 has the auto-inhibition effect in which the Spacer domain in N-terminal interacts with the CUB1 domain in C-terminal, resulting in decreased proteolytic activity. Previous studies reported that exosite-3 in the Spacer domain was a key binding site in the Spacer-CUB1 interaction. When exosite-3 was mutated (R660K/F592Y/R568K/Y661F/Y665F, GOF), the auto-inhibition of ADAMTS13 was disrupted and the enzymatic activity was markedly increased. However, the characteristics of the Spacer-CUB1 interaction is not fully understood. Here, we constructed the model of Spacer-CUB1 complex by homologous modeling and molecular docking to characterize the Spacer-CUB1 binding and predict key amino acid residues via molecular dynamics simulation. Our data showed that G607-S610 was a non-reported potential binding site in the Spacer domain; GOF mutation attenuated the formation of hydrogen bond between exosite-3 and the CUB1 domain; Residues E1231, R1251, L1258, D1259 and T1261 in the CUB1 domain might play an important role in the Spacer-CUB1 interaction. Our study advances the understanding of the structural basis of the auto-inhibition of ADAMTS13 and provides information about the key residues in the binding interface.
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Affiliation(s)
- Junxian Yang
- Institute of Biomechanics/School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China; Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
| | - Zhiwei Wu
- Institute of Biomechanics/School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China; Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
| | - Xubin Xie
- Institute of Biomechanics/School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Guangjian Liu
- Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
| | - Ying Fang
- Institute of Biomechanics/School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Jianhua Wu
- Institute of Biomechanics/School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Jiangguo Lin
- Research Department of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China.
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Kim HJ, Xu Y, Petri A, Vanhoorelbeke K, Crawley JTB, Emsley J. Crystal structure of ADAMTS13 CUB domains reveals their role in global latency. SCIENCE ADVANCES 2021; 7:7/16/eabg4403. [PMID: 33863735 PMCID: PMC8051872 DOI: 10.1126/sciadv.abg4403] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 02/26/2021] [Indexed: 06/12/2023]
Abstract
ADAMTS13 is a plasma metalloprotease that is essential for the regulation of von Willebrand factor (VWF) function, mediator of platelet recruitment to sites of blood vessel damage. ADAMTS13 function is dynamically regulated by structural changes induced by VWF binding that convert it from a latent to active conformation. ADAMTS13 global latency is manifest by the interaction of its C-terminal CUB1-2 domains with its central Spacer domain. We resolved the crystal structure of the ADAMTS13 CUB1-2 domains revealing a previously unreported configuration for the tandem CUB domains. Docking simulations between the CUB1-2 domains with the Spacer domain in combination with enzyme kinetic functional characterization of ADAMTS13 CUB domain mutants enabled the mapping of the CUB1-2 domain site that binds the Spacer domain. Together, these data reveal the molecular basis of the ADAMTS13 Spacer-CUB interaction and the control of ADAMTS13 global latency.
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Affiliation(s)
- H J Kim
- Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Y Xu
- Department of Immunology and Inflammation, Imperial College London, London, UK
| | - A Petri
- Department of Immunology and Inflammation, Imperial College London, London, UK
| | - K Vanhoorelbeke
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - J T B Crawley
- Department of Immunology and Inflammation, Imperial College London, London, UK.
| | - J Emsley
- Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, Nottingham, UK.
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Velásquez Pereira LC, Roose E, Graça NAG, Sinkovits G, Kangro K, Joly BS, Tellier E, Kaplanski G, Falter T, Von Auer C, Rossmann H, Feys HB, Reti M, Prohászka Z, Lämmle B, Voorberg J, Coppo P, Veyradier A, De Meyer SF, Männik A, Vanhoorelbeke K. Immunogenic hotspots in the spacer domain of ADAMTS13 in immune-mediated thrombotic thrombocytopenic purpura. J Thromb Haemost 2021; 19:478-488. [PMID: 33171004 DOI: 10.1111/jth.15170] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/10/2020] [Accepted: 10/28/2020] [Indexed: 01/25/2023]
Abstract
BACKGROUND Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is caused by anti-ADAMTS13 autoantibodies inducing a severe deficiency of ADAMTS13. Epitope mapping studies on samples obtained during acute iTTP episodes have shown that the iTTP immune response is polyclonal, with almost all patients having autoantibodies targeting the spacer domain of ADAMTS13. OBJECTIVES To identify the immunogenic hotspots in the spacer domain of ADAMTS13. PATIENTS/METHODS A library of 11 full-length ADAMTS13 spacer hybrids was created in which amino acid regions of the spacer domain of ADAMTS13 were exchanged by the corresponding region of the spacer domain of ADAMTS1. Next, the full-length ADAMTS13 spacer hybrids were used in enzyme-linked immunosorbent assay to epitope map anti-spacer autoantibodies in 138 samples from acute and remission iTTP patients. RESULTS Sixteen different anti-spacer autoantibody profiles were identified with a similar distribution in acute and remission patients. There was no association between the anti-spacer autoantibody profiles and disease severity. Almost all iTTP samples contained anti-spacer autoantibodies against the following three regions: amino acid residues 588-592, 602-610, and 657-666 (hybrids E, G, and M). Between 31% and 57% of the samples had anti-spacer autoantibodies against amino acid regions 572-579, 629-638, 667-676 (hybrids C, J, and N). In contrast, none of the samples had anti-spacer autoantibodies against amino acid regions 556-563, 564-571, 649-656, and 677-685 (hybrids A, B, L, and O). CONCLUSION We identified three hotspot regions (amino acid regions 588-592, 602-610, and 657-666) in the spacer domain of ADAMTS13 that are targeted by anti-spacer autoantibodies found in a large cohort of iTTP patients.
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Affiliation(s)
| | - Elien Roose
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Nuno A G Graça
- Department of Molecular and Cellular Hemostasis, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Icosagen Cell Factory OÜ, Kambia vald, Tartumaa, Estonia
| | - György Sinkovits
- Department of Internal Medicine and Hematology, and Research Group of Immunology and Hematology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Kadri Kangro
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Bérangère S Joly
- Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut de Recherche Saint Louis, Université de Paris, Paris, France
| | - Edwige Tellier
- INSERM, INRAE, C2VN, Aix-Marseille Univ, Marseille, France
- APHM, INSERM, C2VN, CHU Conception, Service de Médecine Interne et Immunologie Clinique, Aix-Marseille Univ, Marseille, France
| | | | - Tanja Falter
- Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center, Johannes Gutenberg University, Mainz, Germany
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Charis Von Auer
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Department of Hematology, Oncology and Pneumology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Heidi Rossmann
- Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center, Johannes Gutenberg University, Mainz, Germany
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Hendrik B Feys
- Transfusion Research Center, Belgian Red Cross-Flanders, Ghent, Belgium
- Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Marienn Reti
- Department of Haematology and Stem Cell Transplantation, Central Hospital of Southern Pest, National Institute of Haematology and Infectious Diseases, Budapest, Hungary
| | - Zoltán Prohászka
- Department of Internal Medicine and Hematology, and Research Group of Immunology and Hematology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Bernhard Lämmle
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Haemostasis Research Unit, University College London, London, UK
| | - Jan Voorberg
- Department of Molecular and Cellular Hemostasis, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Paul Coppo
- Service d'hématologie, Hôpital Saint-Antoine, Assistance Publique - Hôpitaux de Paris, Paris, France
- Université Sorbonne Paris Cité, Paris, France
| | - Agnès Veyradier
- Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut de Recherche Saint Louis, Université de Paris, Paris, France
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Andres Männik
- Icosagen Cell Factory OÜ, Kambia vald, Tartumaa, Estonia
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
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11
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Graça NAG, Ercig B, Pereira LCV, Kangro K, Kaijen P, Nicolaes GAF, Veyradier A, Coppo P, Vanhoorelbeke K, Männik A, Voorberg J. Modifying ADAMTS13 to modulate binding of pathogenic autoantibodies of patients with acquired thrombotic thrombocytopenic purpura. Haematologica 2020; 105:2619-2630. [PMID: 33131251 PMCID: PMC7604655 DOI: 10.3324/haematol.2019.226068] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 11/21/2019] [Indexed: 11/09/2022] Open
Abstract
Antibodies that develop in patients with immune thrombotic thrombocytopenic purpura (iTTP) commonly target the spacer epitope R568/F592/R660/Y661/Y665 (RFRYY). In this study we present a detailed contribution of each residue in this epitope for autoantibody binding. Different panels of mutations were introduced here to create a large collection of full-length ADAMTS13 variants comprising conservative (Y←→F), semi-conservative (Y/F→L), non-conservative (Y/F→N) or alanine (Y/F/R→A) substitutions. Previously reported Gain-of-Function (GoF, KYKFF) and truncated 'MDTCS' variants were also included. Sera of 18 patients were screened against all variants. Conservative mutations of the aromatic residues did not reduce the binding of autoantibodies. Moderate resistance was achieved by replacing R568 and R660 by lysines or alanines. Semi-conservative mutations of aromatic residues show a moderate effectiveness in autoantibody resistance. Non-conservative asparagine or alanine mutations of aromatic residues are the most effective. In the mixtures of autoantibodies from the majority (89%) of patients screened, autoantibodies targeting the spacer RFRYY epitope have preponderance compared to other epitopes. Reductions in ADAMTS13 proteolytic activity were observed for all full-length mutant variants, in varying degrees. The greatest activity reductions were observed in the most autoantibody-resistant variants (15-35% residual activity in FRETS-VWF73). Among these, a triple-alanine mutant RARAA showed activity in a VWF multimer assay. This study shows that non-conservative and alanine modifications of residues within the exosite-3 spacer RFRYY epitope in full-length ADAMTS13 resist the binding of autoantibodies from iTTP patients, while retaining residual proteolytic activity. Our study provides a framework for the design of autoantibody-resistant ADAMTS13 variants for further therapeutic development.
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Affiliation(s)
- Nuno A. G. Graça
- Icosagen Cell Factory OU, Ossu, Kambja, Tartumaa, Estonia
- Department of Molecular and Cellular Hemostasis, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Bogac Ercig
- Department of Molecular and Cellular Hemostasis, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
- Pharmatarget, Maastricht, the Netherlands
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| | | | - Kadri Kangro
- Laboratory for Thrombosis Research, IRF Life Sciences, KU, Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Paul Kaijen
- Department of Molecular and Cellular Hemostasis, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Gerry A. F. Nicolaes
- Pharmatarget, Maastricht, the Netherlands
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands
| | - Agnès Veyradier
- Service d’Hématologie Biologique and EA3518-Institut Universitaire d’Hématologie, Groupe Hospitalier Saint Louis-Lariboisiere, AP-HP, Universite Paris Diderot, Paris, France
- Centre de Reference des Microangiopathies Thrombotiques, Hopital Saint-Antoine, AP-HP, Paris, France
| | | | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU, Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Andres Männik
- Icosagen Cell Factory OU, Ossu, Kambja, Tartumaa, Estonia
| | - Jan Voorberg
- Department of Molecular and Cellular Hemostasis, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
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12
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Liu L, Ma Z, Zhou X, Yin J, Lu J, Su J, Shen F, Xie L, Hu S, Ling J. Tryptophan 387 and 390 residues in ADAMTS13 are crucial to the ability of vascular tube formation and cell migration of endothelial cells. Clin Exp Pharmacol Physiol 2020; 47:1402-1409. [PMID: 32222985 DOI: 10.1111/1440-1681.13313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 03/04/2020] [Accepted: 03/20/2020] [Indexed: 01/02/2023]
Abstract
A disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13) was mainly generated and secreted from endothelial cells (ECs). Our previous study showed that tryptophan (Trp) residues at 387 and 390 in ADAMTS13 are required for its secretion and enzymatic activity. However, the effects on its host cell as well as the potential mechanism have not been clear. The aim of the study was to examine the effects of Trp residues 387 and 390 of ADAMTS13 on the biological processes of ECs. Herein, Trp was substituted with alanine in ADAMTS13 to generate ADAMTS13 mutants at 387 (W387A), 390 (W390A), and double mutants at 387 and 390 (2WA), respectively. We found that substitution mutation impaired vascular endothelial growth factor (VEGF) secretion and the downstream JAK1/STAT3 activation, the binding ability to Von Willebrand factor, cell proliferation, migration, and vascular tube formation. Overall, our study concluded that Trp387 and Trp390 of ADAMTS13 play vital roles in the biological function of ECs.
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Affiliation(s)
- Ling Liu
- Department of Orthopedics, Clinical Medical Research Center of Jiangsu Province, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhenni Ma
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Xuemei Zhou
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Jie Yin
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Jun Lu
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Jian Su
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Fei Shen
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Liqian Xie
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Shaoyan Hu
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
| | - Jing Ling
- Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China
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13
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Upshaw-Schulman syndrome-associated ADAMTS13 variants possess proteolytic activity at the surface of endothelial cells and in simulated circulation. PLoS One 2020; 15:e0232637. [PMID: 32365113 PMCID: PMC7197795 DOI: 10.1371/journal.pone.0232637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/17/2020] [Indexed: 12/17/2022] Open
Abstract
ADAMTS13 regulates the hemostatic activity of von Willebrand factor (VWF). Determined by static assays, proteolytic activity <10IU/dL in patient plasma, in absence of ADAMTS13 autoantibodies, indicates Upshaw-Schulman syndrome (USS); the congenital form of Thrombotic Thrombocytopenic Purpura (TTP). We have recently functionally characterized sixteen USS-associated ADAMTS13 missense variants under static conditions. Here, we used two assays under shear flow conditions to analyze the activity of those seven mutants with sufficiently high residual secretion plus two newly identified variants. One assay determines cleavage of VWF strings bound to the surface of endothelial cells. The other, light transmission aggregometry-based assay, mimics degradation of VWF-platelet complexes, which are likely to be present in the circulation during TTP bouts. We found that 100 ng/ml of all variants were able to cleave about 80–90% of VWF strings even though 5 out of 9 exhibited activity ≤1% in the state-of-the-art static assay at the same concentration. These data indicate underestimation of ADAMTS13 activity by the used static assay. In simulated circulation, two variants, with missense mutations in the vicinity of the catalytic domain, exhibited only minor residual activity while all other variants were able to effectively break down VWF-platelet complexes. In both assays, significant proteolytic activity could be observed down to 100 ng/ml ADAMTS13. It is thus intriguing to postulate that most variants would have ample activity if secretion of 10% of normal plasma levels could be achieved.
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14
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Zheng L, Abdelgawwad MS, Zhang D, Xu L, Wei S, Cao W, Zheng XL. Histone-induced thrombotic thrombocytopenic purpura in adamts13 -/- zebrafish depends on von Willebrand factor. Haematologica 2020; 105:1107-1119. [PMID: 31753928 PMCID: PMC7109750 DOI: 10.3324/haematol.2019.237396] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/21/2019] [Indexed: 12/30/2022] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is caused by severe deficiency of ADAMTS13 (A13), a plasma metalloprotease that cleaves endothelium-derived von Willebrand factor (VWF). However, severe A13 deficiency alone is often not sufficient to cause an acute TTP; additional factors may be required to trigger the disease. Using CRISPR/Cas9, we created and characterized several novel zebrafish lines carrying a null mutation in a13-/- , vwf, and both. We further used these zebrafish lines to test the hypothesis that inflammation that results in neutrophil activation and release of histone/DNA complexes may trigger TTP. As shown, a13-/- zebrafish exhibit increased levels of plasma VWF antigen, multimer size, and ability of thrombocytes to adhere to a fibrillar collagen-coated surface under flow. The a13-/- zebrafish also show an increased rate of occlusive thrombus formation in the caudal venules after FeCl3 injury. More interestingly, a13-/- zebrafish exhibit ~30% reduction in the number of total, immature, and mature thrombocytes with increased fragmentation of erythrocytes. Administration of a lysine-rich histone results in more severe and persistent thrombocytopenia and a significantly increased mortality rate in a13-/- zebrafish than in wildtype (wt) ones. However, both spontaneous and histone-induced TTP in a13-/- zebrafish are rescued by the deletion of vwf These results demonstrate a potentially mechanistic link between inflammation and the onset of TTP in light of severe A13 deficiency; the novel zebrafish models of TTP may help accelerate our understanding of pathogenic mechanisms and the discoveries of novel therapeutics for TTP and perhaps other arterial thrombotic disorders.
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Affiliation(s)
| | | | - Di Zhang
- Divisions of Laboratory Medicine
| | | | - Shi Wei
- Divisions of Anatomic Pathology, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL, USA
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15
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Abstract
Introduction. The signifi cance of ADAMTS-13 extends beyond its key role in the pathogenesis of thrombotic thrombocytopenic purpura (TTP); there is evidence of a relationship between a decrease in the ADAMTS-13 activity and thrombotic events in acute myocardial infarction and ischemic stroke.Aim. To generalise available information on the structure and function of the metalloprotease ADAMTS-13.General findings. The biological function of ADAMTS-13 consists in the cleavage of ultra-large von Willebrand factor (vWF) multimers. The fact that its defi ciency causes the development of TTP provides a basis for understanding the function of vWF–cleaving protease. ADAMTS-13 has a domain structure. The functional roles of most ADAMTS-13 domains, as well as the key role of the ADAMTS-13-vWF interaction in the regulation of haemostasis, are defi ned. The conformational activation of ADAMTS-13 by vWF constitutes an important aspect of its function. After getting into the bloodstream, ultra-large vWF multimers quickly adopt a closed conformation, which becomes very resistant to ADAMTS-13 proteolysis in the absence of shear stress. Ultra-large plasma vWF multimers regain their sensitivity to ADAMTS-13 after being exposed to high fl uid shear stress, which unfolds the central vWF-A2 domain. The unfolding of a vWF molecule under shear stress conditions reveals previously hidden exosites in domain A2, which gradually increase the binding affi nity between ADAMTS-13 and vWF. The mechanism underlying the production of autoantibodies against ADAMTS-13 is unknown and requires further study. The masking of cryptic epitopes in the closed conformation of ADAMTS-13 prevents the formation of autoantibodies. Early antigen recognition of ADAMTS-13 occurs through surface-exposed epitopes in the C-terminal domains. More detailed information on the mechanisms underlying the interaction between ADAMTS-13 and the vWF can improve the understanding of mechanisms involved in the regulation of the coagulation system.Conflict of interest: the authors declare no confl ict of interest.Financial disclosure: the study had no sponsorship.
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Affiliation(s)
- A. V. Koloskov
- North-Western State Medical University named after I.I. Mechnikov
| | - A. A. Mangushlo
- North-Western State Medical University named after I.I. Mechnikov
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16
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Crystal structure and substrate-induced activation of ADAMTS13. Nat Commun 2019; 10:3781. [PMID: 31439947 PMCID: PMC6706451 DOI: 10.1038/s41467-019-11474-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/03/2019] [Indexed: 11/08/2022] Open
Abstract
Platelet recruitment to sites of blood vessel damage is highly dependent upon von Willebrand factor (VWF). VWF platelet-tethering function is proteolytically regulated by the metalloprotease ADAMTS13. Proteolysis depends upon shear-induced conformational changes in VWF that reveal the A2 domain cleavage site. Multiple ADAMTS13 exosite interactions are involved in recognition of the unfolded A2 domain. Here we report through kinetic analyses that, in binding VWF, the ADAMTS13 cysteine-rich and spacer domain exosites bring enzyme and substrate into proximity. Thereafter, binding of the ADAMTS13 disintegrin-like domain exosite to VWF allosterically activates the adjacent metalloprotease domain to facilitate proteolysis. The crystal structure of the ADAMTS13 metalloprotease to spacer domains reveals that the metalloprotease domain exhibits a latent conformation in which the active-site cleft is occluded supporting the requirement for an allosteric change to enable accommodation of the substrate. Our data demonstrate that VWF functions as both the activating cofactor and substrate for ADAMTS13.
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17
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Colige A, Monseur C, Crawley JTB, Santamaria S, de Groot R. Proteomic discovery of substrates of the cardiovascular protease ADAMTS7. J Biol Chem 2019; 294:8037-8045. [PMID: 30926607 PMCID: PMC6527163 DOI: 10.1074/jbc.ra119.007492] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/28/2019] [Indexed: 12/23/2022] Open
Abstract
The protease ADAMTS7 functions in the extracellular matrix (ECM) of the cardiovascular system. However, its physiological substrate specificity and mechanism of regulation remain to be explored. To address this, we conducted an unbiased substrate analysis using terminal amine isotopic labeling of substrates (TAILS). The analysis identified candidate substrates of ADAMTS7 in the human fibroblast secretome, including proteins with a wide range of functions, such as collagenous and noncollagenous extracellular matrix proteins, growth factors, proteases, and cell-surface receptors. It also suggested that autolysis occurs at Glu-729-Val-730 and Glu-732-Ala-733 in the ADAMTS7 Spacer domain, which was corroborated by N-terminal sequencing and Western blotting. Importantly, TAILS also identified proteolysis of the latent TGF-β-binding proteins 3 and 4 (LTBP3/4) at a Glu-Val and Glu-Ala site, respectively. Using purified enzyme and substrate, we confirmed ADAMTS7-catalyzed proteolysis of recombinant LTBP4. Moreover, we identified multiple additional scissile bonds in an N-terminal linker region of LTBP4 that connects fibulin-5/tropoelastin and fibrillin-1-binding regions, which have an important role in elastogenesis. ADAMTS7-mediated cleavage of LTBP4 was efficiently inhibited by the metalloprotease inhibitor TIMP-4, but not by TIMP-1 and less efficiently by TIMP-2 and TIMP-3. As TIMP-4 expression is prevalent in cardiovascular tissues, we propose that TIMP-4 represents the primary endogenous ADAMTS7 inhibitor. In summary, our findings reveal LTBP4 as an ADAMTS7 substrate, whose cleavage may potentially impact elastogenesis in the cardiovascular system. We also identify TIMP-4 as a likely physiological ADAMTS7 inhibitor.
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Affiliation(s)
- Alain Colige
- Laboratory of Connective Tissue Biology, GIGA, University of Liège, Sart-Tilman, 4000 Liège, Belgium
| | - Christine Monseur
- Laboratory of Connective Tissue Biology, GIGA, University of Liège, Sart-Tilman, 4000 Liège, Belgium
| | - James T B Crawley
- Centre for Haematology, Imperial College London, W12 0NN London, United Kingdom
| | | | - Rens de Groot
- Centre for Haematology, Imperial College London, W12 0NN London, United Kingdom.
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18
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Ling J, Ma Z, Liu L, Yin J, Su J, Shen F, Xie L, Hu S. Identification of a crucial tryptophan residue in ADAMTS13 required for its secretion and enzymatic activity. Clin Exp Pharmacol Physiol 2018; 45:1181-1186. [PMID: 29920743 DOI: 10.1111/1440-1681.12996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 11/27/2022]
Affiliation(s)
- Jing Ling
- Department of Hematology and Oncology; Children's Hospital of Soochow University; Suzhou China
| | - Zhenni Ma
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health; Jiangsu Institute of Hematology; The First Affiliated Hospital of Soochow University; Suzhou China
- Collaborative Innovation Center of Hematology; Soochow University; Suzhou China
| | - Ling Liu
- Department of Orthopedics; Clinical Medical Research Center of Jiangsu Province; The First Affiliated Hospital of Soochow University; Suzhou China
| | - Jie Yin
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health; Jiangsu Institute of Hematology; The First Affiliated Hospital of Soochow University; Suzhou China
- Collaborative Innovation Center of Hematology; Soochow University; Suzhou China
| | - Jian Su
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health; Jiangsu Institute of Hematology; The First Affiliated Hospital of Soochow University; Suzhou China
- Collaborative Innovation Center of Hematology; Soochow University; Suzhou China
| | - Fei Shen
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health; Jiangsu Institute of Hematology; The First Affiliated Hospital of Soochow University; Suzhou China
- Collaborative Innovation Center of Hematology; Soochow University; Suzhou China
| | - Liqian Xie
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health; Jiangsu Institute of Hematology; The First Affiliated Hospital of Soochow University; Suzhou China
- Collaborative Innovation Center of Hematology; Soochow University; Suzhou China
| | - Shaoyan Hu
- Department of Hematology and Oncology; Children's Hospital of Soochow University; Suzhou China
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19
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Hrdinová J, D'Angelo S, Graça NAG, Ercig B, Vanhoorelbeke K, Veyradier A, Voorberg J, Coppo P. Dissecting the pathophysiology of immune thrombotic thrombocytopenic purpura: interplay between genes and environmental triggers. Haematologica 2018; 103:1099-1109. [PMID: 29674502 PMCID: PMC6029525 DOI: 10.3324/haematol.2016.151407] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 04/13/2018] [Indexed: 01/04/2023] Open
Abstract
Although outstanding progress has been made in understanding the pathophysiology of thrombotic thrombocytopenic purpura (TTP), knowledge of the immunopathogenesis of the disease is only at an early stage. Anti-ADAMTS13 auto-antibodies were shown to block proteolysis of von Willebrand factor and/or induce ADAMTS13 clearance from the circulation. However, it still remains to identify which immune cells are involved in the production of anti-ADAMTS13 autoantibodies, and therefore account for the remarkable efficacy of the B-cell depleting agents in this disease. The mechanisms leading to the loss of tolerance of the immune system towards ADAMTS13 involve the predisposing genetic factors of the human leukocyte antigen class II locus DRB1*11 and DQB1*03 alleles as well as the protective allele DRB1*04, and modifying factors such as ethnicity, sex and obesity. Future studies have to identify why these identified genetic risk factors are also frequently to be found in the healthy population although the incidence of immune-mediated thrombotic thrombocytopenic purpura (iTTP) is extremely low. Moreover, the development of recombinant ADAMTS13 opens a new therapeutic era in the field. Interactions of recombinant ADAMTS13 with the immune system of iTTP patients will require intensive investigation, especially for its potential immunogenicity. Better understanding of iTTP immunopathogenesis should, therefore, provide a basis for the development of novel therapeutic approaches to restore immune tolerance towards ADAMTS13 and thereby better prevent refractoriness and relapses in patients with iTTP. In this review, we address these issues and the related challenges in this field.
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Affiliation(s)
- Johana Hrdinová
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,PharmaTarget B.V., Maastricht, the Netherlands.,Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands
| | - Silvia D'Angelo
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Belgium.,Protobios LLC, Tallinn, Estonia
| | - Nuno A G Graça
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,Icosagen Cell Factory OÜ, Ülenurme Vald, Tartumaa, Estonia
| | - Bogac Ercig
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,PharmaTarget B.V., Maastricht, the Netherlands.,Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Belgium
| | - Agnès Veyradier
- Service d'Hématologie Biologique and EA3518, Groupe Hospitalier Saint Louis-Lariboisière, Assistance Publique - Hôpitaux de Paris, Université Paris Diderot, France.,Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine, AP-HP, Paris, France
| | - Jan Voorberg
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Paul Coppo
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine, AP-HP, Paris, France .,Service d'Hématologie, Assistance Publique - Hôpitaux de Paris, France.,Sorbonne Université, UPMC Univ Paris 06, France
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20
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Prediction of spacer-α6 complex: a novel insight into binding of ADAMTS13 with A2 domain of von Willebrand factor under forces. Sci Rep 2018; 8:5791. [PMID: 29636514 PMCID: PMC5893608 DOI: 10.1038/s41598-018-24212-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/28/2018] [Indexed: 12/13/2022] Open
Abstract
Force-regulated cleavage of A2 domain of von Willebrand factor (vWF) by ADAMTS13 is a key event in preventing thrombotic thrombocytopenic purpura (TTP). Recognition and cleavage depend on cooperative and modular contacts between several ADAMTS13 subdomains and discrete segments of vWF A2 domain. Spacer domain of ADAMTS13 contains an important exosite interacting with α6 helix of unfold A2 domain, but it remains unclear whether stretching of α6 regulates binding to spacer. To understand the molecular mechanism underlying the interactions between spacer and α6 under stretching, we successfully predicted spacer-α6 complex by a novel computer strategy combined the steered molecular dynamics (SMD) and flexible docking techniques. This strategy included three steps: (1) constant-velocity SMD simulation of α6; (2) zero-velocity SMD simulations of α6, and (3) flexible dockings of α6 to spacer. In our spacer-α6 complex model, 13 key residues, six in α6 and seven in spacer, were identified. Our data demonstrated a biphasic extension-regulated binding of α6 to spacer. The binding strength of the complex increased with α6 extension until it reaches its optimum of 0.25 nm, and then decreased as α6 extension further increased, meaning that spacer is in favor to binding with a partially extended α6, which may contribute to the optimal contact and proteolysis. Changes of interface area and intermolecular salt bridge may serve as the molecular basis for this characteristic. These findings provide a novel insight into mechano-chemical regulation on interaction between ADAMTS13 and vWF A2 domain under forces.
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Kremer Hovinga JA, Heeb SR, Skowronska M, Schaller M. Pathophysiology of thrombotic thrombocytopenic purpura and hemolytic uremic syndrome. J Thromb Haemost 2018; 16:618-629. [PMID: 29356300 DOI: 10.1111/jth.13956] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Thrombotic microangiopathies are rare disorders characterized by the concomitant occurrence of severe thrombocytopenia, microangiopathic hemolytic anemia, and a variable degree of ischemic end-organ damage. The latter particularly affects the brain, the heart, and the kidneys. The primary forms, thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS), although their clinical presentations often overlap, have distinctive pathophysiologies. TTP is the consequence of a severe ADAMTS-13 deficiency, either immune-mediated as a result of circulating autoantibodies, or caused by mutations in ADAMTS-13. HUS develops following an infection with Shiga-toxin producing bacteria, or as the result of excessive activation of the alternative pathway of the complement system because of mutations in genes encoding complement system proteins.
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Affiliation(s)
- J A Kremer Hovinga
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, Bern, Switzerland
- Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - S R Heeb
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, Bern, Switzerland
- Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - M Skowronska
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, Bern, Switzerland
- Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - M Schaller
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, Bern, Switzerland
- Department for BioMedical Research, University of Bern, Bern, Switzerland
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Studt JD, Voorberg J, Hovinga JA, Schaller M. Acquired thrombotic thrombocytopenic purpura. Hamostaseologie 2018; 33:121-30. [DOI: 10.5482/hamo-12-12-0023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/17/2013] [Indexed: 01/16/2023] Open
Abstract
SummaryThe von Willebrand factor (VWF)-cleaving metalloprotease, ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motifs-13) is the only known target of the dysregulated immune response in acquired TTP. Autoantibodies to ADAMTS13 either neutralize its activity or accelerate its clearance, thereby causing a severe deficiency of ADAMTS13 in plasma. As a consequence, size regulation of VWF is impaired and the persistence of ultra-large VWF (ULVWF) multimers facilitates micro vascular platelet aggregation causing microangiopathic haemolytic anaemia and ischaemic organ damage. Autoimmune TTP although a rare disease with an annual incidence of 1.72 cases has a mortality rate of 20% even with adequate therapy.We describe the mechanisms involved in ADAMTS13 autoimmunity with a focus on the role of B- and T-cells in the pathogenesis of this disorder. We discuss the potential translation of recent experimental findings into future therapeutic concepts for the treatment of acquired TTP.
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Abstract
von Willebrand factor (VWF) is a key player in hemostasis, acting as a carrier for factor VIII and capturing platelets at sites of vascular damage. To capture platelets, it must undergo conformational changes, both within its A1 domain and at the macromolecular level through A2 domain unfolding. Its size and this function are regulated by the metalloproteinase ADAMTS-13. Recently, it has been shown that ADAMTS-13 undergoes a conformational change upon interaction with VWF, and that this enhances its activity towards its substrate. This review summarizes recent work on these conformational transitions, describing how they are controlled. It points to their importance in hemostasis, bleeding disorders, and the developing field of therapeutic application of ADAMTS-13 as an antithrombotic agent in obstructive microvascular thrombosis and in cardiovascular disease.
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Affiliation(s)
- K. South
- Centre for HaematologyImperial College LondonLondonUK
| | - D. A. Lane
- Centre for HaematologyImperial College LondonLondonUK
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Nowak AA, O'Brien HER, Henne P, Doerr A, Vanhoorelbeke K, Laffan MA, McKinnon TAJ. ADAMTS-13 glycans and conformation-dependent activity. J Thromb Haemost 2017; 15:1155-1166. [PMID: 28370891 DOI: 10.1111/jth.13688] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Indexed: 11/30/2022]
Abstract
Essentials The impact of N-linked glycosylation on ADAMTS-13 function has not been fully explored. The activity of glycan modified ADAMTS-13 was investigated under static and shear stress conditions. Terminal sialic acid on the metalloprotease domain glycans are important for ADAMTS-13 activity. The CUB domain glycans modulate ADAMTS-13 activity. SUMMARY Background ADAMTS-13 activity can be regulated by its conformation, whereby interactions between the C-terminal CUB domains and the spacer domain maintain ADAMTS-13 in a closed conformation. ADAMTS-13 contains 10 N-linked glycans, with four sites present in theTSP2 through to CUB domains that may contribute to its conformation. Objectives/Methods We hypothesized that glycosylation contributes to ADAMTS-13 conformation and function. The proteolytic activity of glycan-modified ADAMTS-13 was assessed under static and shear stress conditions. Results Enzymatic removal of terminal silaic acid or entire N-linked glycan chains decreased activity against FRETS-VWF73 at pH 7.4 and against full-length von Willebrand factor (VWF) under shear stress. Using truncated ADAMTS-13, we demonstrated that this was attributable to loss of sialic acid from the glycans in the metalloprotease domain and an effect of N-linked glycosylation in the TSP2 through to CUB domains. Mutation of the N-linked glycan sites in the MDTCS domains reduced or abolished protein expression. However, the N707Q, N828Q, N1235Q and N1354Q (TSP2, TSP4, CUB1, and CUB2 domains, respectively) variants were expressed normally. Interestingly, the N707Q and N828Q variants showed reduced activity against FRETS-VWF73, but normal activity under flow conditions. In contrast, the N1235Q and N1354Q variants had enhanced activity against FRETS-VWF73 and VWF under shear stress. Immunoprecipitation experiments confirmed that loss of N-linked glycans in the CUB domains significantly reduced the interaction with the spacer domain and enhanced binding to the 6A6 anti-ADAMTS-13 antibody, which recognizes a cryptic epitope in the metalloprotease domain. Conclusions Together, these data demonstrate that the N-linked glycans of ADAMTS-13 play a crucial role in regulating ADAMTS-13 activity.
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Affiliation(s)
- A A Nowak
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
| | - H E R O'Brien
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
| | - P Henne
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
| | - A Doerr
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
| | - K Vanhoorelbeke
- Laboratory for Thrombosis Research, Catholic University Leuven, Leuven, Belgium
| | - M A Laffan
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
| | - T A J McKinnon
- Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK
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Abstract
Thrombotic thrombocytopenic purpura (TTP; also known as Moschcowitz disease) is characterized by the concomitant occurrence of often severe thrombocytopenia, microangiopathic haemolytic anaemia and a variable degree of ischaemic organ damage, particularly affecting the brain, heart and kidneys. Acute TTP was almost universally fatal until the introduction of plasma therapy, which improved survival from <10% to 80-90%. However, patients who survive an acute episode are at high risk of relapse and of long-term morbidity. A timely diagnosis is vital but challenging, as TTP shares symptoms and clinical presentation with numerous conditions, including, for example, haemolytic uraemic syndrome and other thrombotic microangiopathies. The underlying pathophysiology is a severe deficiency of the activity of a disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13), the protease that cleaves von Willebrand factor (vWF) multimeric strings. Ultra-large vWF strings remain uncleaved after endothelial cell secretion and anchorage, bind to platelets and form microthrombi, leading to the clinical manifestations of TTP. Congenital TTP (Upshaw-Schulman syndrome) is the result of homozygous or compound heterozygous mutations in ADAMTS13, whereas acquired TTP is an autoimmune disorder caused by circulating anti-ADAMTS13 autoantibodies, which inhibit the enzyme or increase its clearance. Consequently, immunosuppressive drugs, such as corticosteroids and often rituximab, supplement plasma exchange therapy in patients with acquired TTP.
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Jeong WJ, Kye M, Han SH, Choi JS, Lim YB. Inhibition of Multimolecular RNA-Protein Interactions Using Multitarget-Directed Nanohybrid System. ACS APPLIED MATERIALS & INTERFACES 2017; 9:11537-11545. [PMID: 28287257 DOI: 10.1021/acsami.7b01517] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Multitarget-directed ligands (MTDLs) are hybrid ligands obtained by covalently linking active pharmacophores that can act on different targets. We envision that the concept of MTDLs can also be applied to supramolecular bioinorganic nanohybrid systems. Here, we report the inhibition of multimolecular RNA-protein complexes using multitarget-directed peptide-carbon nanotube hybrids (SPCHs). One of the most well-characterized and important RNA-protein interactions, a Rev-response element (RRE) RNA:Rev protein:Crm1 protein interaction system in human immunodeficiency virus type-1, was used as a model of multimolecular RNA-protein interactions. Although all previous studies have targeted only one of the interaction interfaces, that is, either the RRE:Rev interface or the RRE-Rev complex:Crm1 interface, we here have developed multitarget-directed SPCHs that could target both interfaces because the supramolecular nanosystem could be best suited for inhibiting multimolecular RNA-protein complexes that are characterized by large and complex molecular interfaces. The results showed that the single target-directed SPCHs were inhibitory to the single interface comprised only of RNA and protein in vitro, whereas multitarget-directed SPCHs were inhibitory to the multimolecular RNA-protein interfaces both in vitro and in cellulo. The MTDL nanohybrids represent a novel nanotherapeutic system that could be used to treat complex disease targets.
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Affiliation(s)
- Woo-Jin Jeong
- Department of Materials Science & Engineering, Yonsei University , Seoul 03722, Korea
| | - Mahnseok Kye
- Department of Materials Science & Engineering, Yonsei University , Seoul 03722, Korea
| | - So-Hee Han
- Department of Materials Science & Engineering, Yonsei University , Seoul 03722, Korea
| | - Jun Shik Choi
- Department of Materials Science & Engineering, Yonsei University , Seoul 03722, Korea
| | - Yong-Beom Lim
- Department of Materials Science & Engineering, Yonsei University , Seoul 03722, Korea
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The class I scavenger receptor CD163 promotes internalization of ADAMTS13 by macrophages. Blood Adv 2017; 1:293-305. [PMID: 29296945 DOI: 10.1182/bloodadvances.2016001321] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/19/2016] [Indexed: 01/07/2023] Open
Abstract
Internalization of ADAMTS13 by macrophages may contribute to its clearance from the circulation. Here we investigated endocytic mechanisms that contribute to the uptake of ADAMTS13 by macrophages. Human monocyte-derived macrophages were used to monitor the uptake of fluorescently labeled recombinant ADAMTS13 by flow cytometry. Internalization of ADAMTS13 was blocked upon addition of the cell-permeable dynamin inhibitor dynasore. Partial blocking of ADAMTS13 uptake was observed by using mannan; however, uptake was not affected by an antibody that blocked binding to the macrophage mannose receptor CD206, which suggests that other endocytic receptors contribute to the internalization of ADAMTS13 by macrophages. A pull-down with ADAMTS13 and subsequent mass spectrometric analysis identified the class I scavenger receptor CD163 as a candidate receptor for ADAMTS13. Blocking experiments with monoclonal anti-CD163 antibody EDHu-1 resulted in decreased ADAMTS13 internalization by macrophages. Pronounced inhibition of ADAMTS13 uptake by EDHu-1 was observed in CD163 high-expressing macrophages. In agreement with these findings, CD163-expressing Chinese hamster ovary cells were capable of rapidly internalizing ADAMTS13. Surface plasmon resonance revealed binding of ADAMTS13 to scavenger receptor cysteine-rich domains 1-9 and 1-5 of CD163. Taken together, our data identify CD163 as a major endocytic receptor for ADAMTS13 on macrophages.
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South K, Freitas MO, Lane DA. Conformational quiescence of ADAMTS-13 prevents proteolytic promiscuity. J Thromb Haemost 2016; 14:2011-2022. [PMID: 27514025 PMCID: PMC5111603 DOI: 10.1111/jth.13445] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Indexed: 11/29/2022]
Abstract
Essentials Recently, ADAMTS-13 has been shown to undergo substrate induced conformation activation. Conformational quiescence of ADAMTS-13 may serve to prevent off-target proteolysis in plasma. Conformationally active ADAMTS-13 variants are capable of proteolysing the Aα chain of fibrinogen. This should be considered as ADAMTS-13 variants are developed as potential therapeutic agents. Click to hear Dr Zheng's presentation on structure function and cofactor-dependent regulation of ADAMTS-13 SUMMARY: Background Recent work has revealed that ADAMTS-13 circulates in a 'closed' conformation, only fully interacting with von Willebrand factor (VWF) following a conformational change. We hypothesized that this conformational quiescence also maintains the substrate specificity of ADAMTS-13 and that the 'open' conformation of the protease might facilitate proteolytic promiscuity. Objectives To identify a novel substrate for a constitutively active gain of function (GoF) ADAMTS-13 variant (R568K/F592Y/R660K/Y661F/Y665F). Methods Fibrinogen proteolysis was characterized using SDS PAGE and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Fibrin formation was monitored by turbidity measurements and fibrin structure visualized by confocal microscopy. Results ADAMTS-13 exhibits proteolytic activity against the Aα chain of human fibrinogen, but this is only manifest on its conformational activation. Accordingly, the GoF ADAMTS-13 variant and truncated variants such as MDTCS exhibit this activity. The cleavage site has been determined by LC-MS/MS to be Aα chain Lys225-Met226. Proteolysis of fibrinogen by GoF ADAMTS-13 impairs fibrin formation in plasma-based assays, alters clot structure and increases clot permeability. Although GoF ADAMTS-13 does not appear to proteolyse preformed cross-linked fibrin, its proteolytic activity against fibrinogen increases the susceptibility of fibrin to tissue-type plasminogen activator (t-PA)-induced lysis by plasmin and increases the fibrin clearance rate more than 8-fold compared with wild-type (WT) ADAMTS-13 (EC50 values of 3.0 ± 1.7 nm and 25.2 ± 9.7 nm, respectively) in in vitro thrombosis models. Conclusion The 'closed' conformation of ADAMTS-13 restricts its specificity and protects against fibrinogenolysis. Induced substrate promiscuity will be important as ADAMTS-13 variants are developed as potential therapeutic agents against thrombotic thrombocytopenic purpura (TTP) and other cardiovascular diseases.
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Affiliation(s)
- K South
- Centre for Haematology, Imperial College London, London, UK.
| | - M O Freitas
- Centre for Haematology, Imperial College London, London, UK
| | - D A Lane
- Centre for Haematology, Imperial College London, London, UK
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Underwood M, Peyvandi F, Garagiola I, Machin S, Mackie I. Degradation of two novel congenital TTP ADAMTS13 mutants by the cell proteasome prevents ADAMTS13 secretion. Thromb Res 2016; 147:16-23. [PMID: 27665541 DOI: 10.1016/j.thromres.2016.09.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Over 150 mutations have been identified in the ADAMTS13 gene in patients with congenital thrombotic thrombocytopenic purpura (TTP). The majority of these (86%), lead to reduced (<50%) secretion of mutant recombinant ADAMTS13. The mechanism by which this occurs has not been investigated in vitro. Two novel ADAMTS13 mutations (p.I143T and p.Y570C) identified in two congenital adolescence onset TTP patients were studied, to investigate their effects on ADAMTS13 secretion and subcellular localisation. MATERIALS AND METHODS HEK293T cells were transiently transfected with wild type or mutant ADAMTS13 cDNA. Immunofluorescence and confocal microscopy were used to study localisation within the endoplasmic reticulum (ER) and Golgi. The cell proteasome and lysosomes were inhibited in cells stably expressing ADAMTS13 to investigate degradation of ADAMTS13 by either organelle. RESULTS Both mutations severely impaired secretion and both mutants localised within the ER and Golgi. Proteasome inhibition led to the intracellular accumulation of both mutants, suggesting proteasome degradation. Lysosome inhibition on the other hand did not lead to increased intracellular accumulation of the mutants. CONCLUSIONS Proteasome degradation of these ADAMTS13 mutants contributed to their reduced secretion.
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Affiliation(s)
- Mary Underwood
- Haemostasis Research Unit, University College London, London, England; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
| | - Flora Peyvandi
- Haemostasis Research Unit, University College London, London, England; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy; Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Isabella Garagiola
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Samuel Machin
- Haemostasis Research Unit, University College London, London, England
| | - Ian Mackie
- Haemostasis Research Unit, University College London, London, England
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Ostertag EM, Kacir S, Thiboutot M, Gulendran G, Zheng XL, Cines DB, Siegel DL. ADAMTS13 autoantibodies cloned from patients with acquired thrombotic thrombocytopenic purpura: 1. Structural and functional characterization in vitro. Transfusion 2016; 56:1763-74. [PMID: 27040144 PMCID: PMC4938786 DOI: 10.1111/trf.13584] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 01/25/2016] [Accepted: 02/06/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND Acquired thrombotic thrombocytopenia purpura (TTP) is a life-threatening illness caused by autoantibodies that decrease the activity of ADAMTS13, the von Willebrand factor-cleaving protease. Despite efficacy of plasma exchange, mortality remains high and relapse is common. Improved therapies may come from understanding the diversity of pathogenic autoantibodies on a molecular or genetic level. Cloning comprehensive repertoires of patient autoantibodies can provide the necessary tools for studying immunobiology of disease and developing animal models. STUDY DESIGN AND METHODS Anti-ADAMTS13 antibodies were cloned from four patients with acquired TTP using phage display and characterized with respect to genetic origin, inhibition of ADAMTS13 proteolytic activity, and epitope specificity. Anti-idiotypic antisera raised to a subset of autoantibodies enabled comparison of their relatedness to each other and to polyclonal immunoglobulin (Ig)G in patient plasma. RESULTS Fifty-one unique antibodies were isolated comprising epitope specificities resembling the diversity found in circulating patient IgG. Antibodies directed both to the amino terminal domains and to those requiring the ADAMTS13 cysteine-rich/spacer region for binding inhibited proteolytic activity, while those solely targeting carboxy-terminal domains were noninhibitory. Anti-idiotypic antisera raised to a subset of antibody clones crossreacted with and reduced the inhibitory activity of polyclonal IgG from a set of unrelated patients. CONCLUSIONS Anti-ADAMTS13 autoantibodies isolated by repertoire cloning display the diversity of epitope specificities found in patient plasma and provide tools for developing animal models of acquired TTP. Shared idiotypes of inhibitory clones with circulating IgG from multiple patients suggest common features of pathogenic autoantibodies that could be exploited for developing more targeted therapies.
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Affiliation(s)
- Eric M. Ostertag
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
| | - Stephen Kacir
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
| | - Michelle Thiboutot
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
| | - Gayathri Gulendran
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
| | - X. Long Zheng
- Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Douglas B. Cines
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
| | - Don L. Siegel
- Departments of Pathology & Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania
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ADAM and ADAMTS Family Proteins and Snake Venom Metalloproteinases: A Structural Overview. Toxins (Basel) 2016; 8:toxins8050155. [PMID: 27196928 PMCID: PMC4885070 DOI: 10.3390/toxins8050155] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 05/02/2016] [Accepted: 05/04/2016] [Indexed: 01/01/2023] Open
Abstract
A disintegrin and metalloproteinase (ADAM) family proteins constitute a major class of membrane-anchored multidomain proteinases that are responsible for the shedding of cell-surface protein ectodomains, including the latent forms of growth factors, cytokines, receptors and other molecules. Snake venom metalloproteinases (SVMPs) are major components in most viper venoms. SVMPs are primarily responsible for hemorrhagic activity and may also interfere with the hemostatic system in envenomed animals. SVMPs are phylogenetically most closely related to ADAMs and, together with ADAMs and related ADAM with thrombospondin motifs (ADAMTS) family proteinases, constitute adamalysins/reprolysins or the M12B clan (MEROPS database) of metalloproteinases. Although the catalytic domain structure is topologically similar to that of other metalloproteinases such as matrix metalloproteinases, the M12B proteinases have a modular structure with multiple non-catalytic ancillary domains that are not found in other proteinases. Notably, crystallographic studies revealed that, in addition to the conserved metalloproteinase domain, M12B members share a hallmark cysteine-rich domain designated as the “ADAM_CR” domain. Despite their name, ADAMTSs lack disintegrin-like structures and instead comprise two ADAM_CR domains. This review highlights the current state of our knowledge on the three-dimensional structures of M12B proteinases, focusing on their unique domains that may collaboratively participate in directing these proteinases to specific substrates.
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Human neutrophil peptides inhibit cleavage of von Willebrand factor by ADAMTS13: a potential link of inflammation to TTP. Blood 2016; 128:110-9. [PMID: 27207796 DOI: 10.1182/blood-2015-12-688747] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 04/30/2016] [Indexed: 12/16/2022] Open
Abstract
Infection or inflammation may precede and trigger formation of microvascular thrombosis in patients with acquired thrombotic thrombocytopenic purpura (TTP). However, the mechanism underlying this clinical observation is not fully understood. Here, we show that human neutrophil peptides (HNPs) released from activated and degranulated neutrophils inhibit proteolytic cleavage of von Willebrand factor (VWF) by ADAMTS13 in a concentration-dependent manner. Half-maximal inhibitory concentrations of native HNPs toward ADAMTS13-mediated proteolysis of peptidyl VWF73 and multimeric VWF are 3.5 μM and 45 μM, respectively. Inhibitory activity of HNPs depends on the RRY motif that is shared by the spacer domain of ADAMTS13. Native HNPs bind to VWF73 (KD = 0.72 μM), soluble VWF (KD = 0.58 μM), and ultra-large VWF on endothelial cells. Enzyme-linked immunosorbent assay (ELISA) demonstrates markedly increased plasma HNPs1-3 in most patients with acquired autoimmune TTP at presentation (median, ∼170 ng/mL; range, 58-3570; n = 19) compared with healthy controls (median, ∼23 ng/mL; range, 6-44; n = 18) (P < .0001). Liquid chromatography plus tandem mass spectrometry (LC-MS/MS) reveals statistically significant increases of HNP1, HNP2, and HNP3 in patient samples (all P values <.001). There is a good correlation between measurement of HNPs1-3 by ELISA and by LC-MS/MS (Spearman ρ = 0.7932, P < .0001). Together, these results demonstrate that HNPs1-3 may be potent inhibitors of ADAMTS13 activity, likely by binding to the central A2 domain of VWF and physically blocking ADAMTS13 binding. Our findings may provide a novel link between inflammation/infection and the onset of microvascular thrombosis in acquired TTP and potentially other immune thrombotic disorders.
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Abstract
PURPOSE OF REVIEW ADAMTS13 is a zinc-containing metalloprotease that cleaves von Willebrand factor (VWF). Deficiency of plasma ADAMTS13 activity is accountable for a potentially fatal blood disorder thrombotic thrombocytopenic purpura (TTP). Understanding of ADAMTS13-VWF interaction is essential for developing novel treatments to this disorder. RECENT FINDINGS Despite the proteolytic activity of ADAMTS13 being restricted to the metalloprotease domain, the ancillary proximal C-terminal domains including the disintegrin domain, first TSP-1 repeat, cysteine-rich region, and spacer domain are all required for cleavage of VWF and its analogs. Recent studies have added to our understandings of the role of the specific regions in the disintegrin domain, the cysteine-rich domain, and the spacer domain responsible for its interaction with VWF. Additionally, regulative functions of the distal portion of ADAMTS13 including the TSP-1 2-8 repeats and the CUB domains have been proposed. Finally, fine mapping of anti-ADAMTS13 antibody epitopes have provided further insight into the essential structural elements in ADAMTS13 for VWF binding and the mechanism of autoantibody-mediated TTP. SUMMARY Significant progress has been made in our understandings of the structure-function relationship of ADAMTS13 in the past decade. To further investigate ADAMTS13-VWF interactions for medical applications, these interactions must be studied under physiological conditions in vivo.
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Abstract
Pathogenesis of thrombotic thrombocytopenic purpura (TTP) was a mystery for over half a century until the discovery of ADAMTS13. ADAMTS13 is primarily synthesized in the liver, and its main function is to cleave von Willebrand factor (VWF) anchored on the endothelial surface, in circulation, and at the sites of vascular injury. Deficiency of plasma ADAMTS13 activity (<10%) resulting from mutations of the ADAMTS13 gene or autoantibodies against ADAMTS13 causes hereditary or acquired (idiopathic) TTP. ADAMTS13 activity is usually normal or modestly reduced (>20%) in other forms of thrombotic microangiopathy secondary to hematopoietic progenitor cell transplantation, infection, and disseminated malignancy or in hemolytic uremic syndrome. Plasma infusion or exchange remains the initial treatment of choice to date, but novel therapeutics such as recombinant ADAMTS13 and gene therapy are under development. Moreover, ADAMTS13 deficiency has been shown to be a risk factor for the development of myocardial infarction, stroke, cerebral malaria, and preeclampsia.
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Affiliation(s)
- X Long Zheng
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia and The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104;
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Ma Z, Su J, Zhang J, Ling J, Yin J, Bai X, Ruan C. The co-influence of VWD type 2B/2M mutations in the A1 domain and platelet GPIbα on the rate of cleavage to VWF by ADAMTS13. Thromb Res 2015; 136:987-95. [PMID: 26345337 DOI: 10.1016/j.thromres.2015.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 06/16/2015] [Accepted: 08/11/2015] [Indexed: 10/23/2022]
Abstract
INTRODUCTION In plasma, the size of the von Willebrand factor (VWF) multimer is down-regulated by ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13). The binding of platelets or glycoprotein (GP) Ibα recombinant fragment to VWF domain A1 may increase the cleavage by ADAMTS13 to VWF. Both type 2B and type 2M von Willebrand disease (VWD) result in bleeding disorders with the diathesis of increased and decreased binding affinity between GPIbα and VWF, respectively. However, the influence of 2B/2M VWD mutations in the A1 domain and GPIbα on cleavage by ADAMTS13 to VWF needs further study. MATERIALS AND METHODS Different types of full-length human recombinant VWF (rVWF) were expressed, including three type 2B mutations (P1337L, H1268D, and R1308C), one type 2M mutation (D1302G), and wild type (WT). The three characterized types of rVWF were digested by ADAMTS13 under static conditions or high-shear stress. The interaction of rVWF and ADAMTS13 was also tested by plate-binding assays. RESULTS Under static (natured) conditions or high-shear stress, type 2B mutants exhibited a higher susceptibility to ADAMTS13 than rVWF-WT, whereas type 2M mutant was normal. While under static (denatured) conditions or high-shear stress (with GPIbα fragment) rVWF-WT showed an even higher susceptibility to ADAMTS13 than the two type 2B mutants studied. CONCLUSION Type 2B mutations localized in the A1 domain could enhance the sensitivity to ADAMTS13-mediated proteolysis. When GPIbα participated, there was a dramatically increased proteolytic cleavage of VWF by ADAMTS13 to rVWF-WT, excluding some type 2B mutants.
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Affiliation(s)
- Zhenni Ma
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China
| | - Jian Su
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China
| | - Jingyu Zhang
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China; Department of Hematology, Hebei Institute of Hematology, The Second Hospital of Hebei Medical University, 215 Hepingxi Road, Shijiazhuang 050000, China
| | - Jing Ling
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China; Department of Hematology and Oncology, Children's Hospital of Soochow University, 303 Jingde Road, Suzhou 215003, China
| | - Jie Yin
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China
| | - Xia Bai
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China
| | - Changgeng Ruan
- MOH Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Collaborative Innovation Center of Hematology, Soochow University, 1 Shizi Street, Suzhou 215006, China.
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High-resolution epitope mapping by HX MS reveals the pathogenic mechanism and a possible therapy for autoimmune TTP syndrome. Proc Natl Acad Sci U S A 2015. [PMID: 26203127 DOI: 10.1073/pnas.1512561112] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acquired thrombotic thrombocytopenic purpura (TTP), a thrombotic disorder that is fatal in almost all cases if not treated promptly, is primarily caused by IgG-type autoantibodies that inhibit the ability of the ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) metalloprotease to cleave von Willebrand factor (VWF). Because the mechanism of autoantibody-mediated inhibition of ADAMTS13 activity is not known, the only effective therapy so far is repeated whole-body plasma exchange. We used hydrogen-deuterium exchange mass spectrometry (HX MS) to determine the ADAMTS13 binding epitope for three representative human monoclonal autoantibodies, isolated from TTP patients by phage display as tethered single-chain fragments of the variable regions (scFvs). All three scFvs bind the same conformationally discontinuous epitopic region on five small solvent-exposed loops in the spacer domain of ADAMTS13. The same epitopic region is also bound by most polyclonal IgG autoantibodies in 23 TTP patients that we tested. The ability of ADAMTS13 to proteolyze VWF is impaired by the binding of autoantibodies at the epitopic loops in the spacer domain, by the deletion of individual epitopic loops, and by some local mutations. Structural considerations and HX MS results rule out any disruptive structure change effect in the distant ADAMTS13 metalloprotease domain. Instead, it appears that the same ADAMTS13 loop segments that bind the autoantibodies are also responsible for correct binding to the VWF substrate. If so, the autoantibodies must prevent VWF proteolysis simply by physically blocking normal ADAMTS13 to VWF interaction. These results point to the mechanism for autoantibody action and an avenue for therapeutic intervention.
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Lu RN, Yang S, Wu HM, Zheng XL. Unconjugated bilirubin inhibits proteolytic cleavage of von Willebrand factor by ADAMTS13 protease. J Thromb Haemost 2015; 13:1064-72. [PMID: 25782102 PMCID: PMC4599575 DOI: 10.1111/jth.12901] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 03/03/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND Bilirubin is a yellow breakdown product of heme catabolism. Increased serum levels of unconjugated bilirubin are conditions commonly seen in premature neonates and adults with acute hemolysis including thrombotic microangiopathy. Previous studies have shown that unconjugated bilirubin lowers plasma ADAMTS13 activity, but the mechanism is not fully understood. OBJECTIVES The study is to determine whether unconjugated bilirubin directly inhibits the cleavage of von Willebrand factor (VWF) and its analogs by ADAMTS13. METHODS Fluorogenic, surface-enhanced laser desorption/ionization time-of-flight mass spectrometric assay, and Western blotting analyses were used to address this question. RESULTS Unconjugated bilirubin inhibits the cleavage of F485-rVWF73-H, D633-rVWF73-H, and GST-rVWF71-11K by ADAMTS13 in a concentration-dependent manner with a half-maximal inhibitory concentration of ~13, ~70, and ~17 μmol L(-1) , respectively. Unconjugated bilirubin also dose-dependently inhibits the cleavage of multimeric VWF by ADAMTS13 under denaturing conditions. The inhibitory activity of bilirubin on the cleavage of D633-rVWF73-H and multimeric VWF, but not F485-rVWF73-H, was eliminated after incubation with bilirubin oxidase that converts bilirubin to biliverdin. Furthermore, plasma ADAMTS13 activity in patients with hyperbilirubinemia increased after treatment with bilirubin oxidase. CONCLUSIONS Unconjugated bilirubin directly inhibits ADAMTS13's ability to cleave both peptidyl and native VWF substrates in addition to its interference with certain fluorogenic assays. Our findings may help proper interpretation of ADAMTS13 results under pathological conditions. Whether elevated serum unconjugated bilirubin has prothrombotic effect in vivo remains to be determined in our future study.
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Affiliation(s)
- Rui-Nan Lu
- Division of Laboratory Medicine, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL
- Department of Hematology, the First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, China
| | - Shangbin Yang
- Department of Pathology, Ohio State University, Columbus, OH
| | - Haifeng M. Wu
- Department of Pathology, Ohio State University, Columbus, OH
| | - X. Long Zheng
- Division of Laboratory Medicine, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL
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Abstract
In this issue of Blood, de Groot et al identify a hydrophobic pocket in the Cys-rich domain of ADAMTS13 that appears to interact with the hydrophobic pocket in the central A2 domain of von Willebrand factor (VWF) for its proteolysis.
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Abstract
ADAMTS13 proteolytically regulates the platelet-tethering function of von Willebrand factor (VWF). ADAMTS13 function is dependent upon multiple exosites that specifically bind the unraveled VWF A2 domain and enable proteolysis. We carried out a comprehensive functional analysis of the ADAMTS13 cysteine-rich (Cys-rich) domain using engineered glycans, sequence swaps, and single point mutations in this domain. Mutagenesis of Cys-rich domain-charged residues had no major effect on ADAMTS13 function, and 5 out of 6 engineered glycans on the Cys-rich domain also had no effect on ADAMTS13 function. However, a glycan attached at position 476 appreciably reduced both VWF binding and proteolysis. Substitution of Cys-rich sequences for the corresponding regions in ADAMTS1 identified a hydrophobic pocket involving residues Gly471-Val474 as being of critical importance for both VWF binding and proteolysis. Substitution of hydrophobic VWF A2 domain residues to serine in a region (residues 1642-1659) previously postulated to interact with the Cys-rich domain revealed the functional importance of VWF residues Ile1642, Trp1644, Ile1649, Leu1650, and Ile1651. Furthermore, the functional deficit of the ADAMTS13 Cys-rich Gly471-Val474 variant was dependent on these same hydrophobic VWF residues, suggesting that these regions form complementary binding sites that directly interact to enhance the efficiency of the proteolytic reaction.
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Bao J, Xiao J, Mao Y, Zheng XL. Carboxyl terminus of ADAMTS13 directly inhibits platelet aggregation and ultra large von Willebrand factor string formation under flow in a free-thiol-dependent manner. Arterioscler Thromb Vasc Biol 2013; 34:397-407. [PMID: 24357063 DOI: 10.1161/atvbaha.113.302547] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE ADAMTS13 (A Disintegrin And Metalloprotease with Thrombospondin type 1 repeats, 13) cleaves von Willebrand factor (VWF), thereby inhibiting thrombus formation. Proteolytic cleavage relies on the amino-terminal (MDTCS) domains, but the role of the more distal carboxyl-terminal domains of ADAMTS13 is not fully understood. A previous study demonstrated the presence of multiple surface-exposed free sulfhydryls on ADAMTS13 that seemed to interact with those on VWF under shear. Here, we determined the physiological relevance of such an interaction in antithrombotic responses under flow. APPROACH AND RESULTS A microfluidic assay demonstrated that a carboxyl-terminal fragment of ADAMTS13, comprising either 2 to 8 thrombospondin type 1 (TSP1) repeats and CUB domains (T2C) or 5 to 8 Thrombospondin type 1 (TSP1) repeats and CUB domains (T5C), directly inhibited platelet adhesion/aggregation on a collagen surface under arterial shear. In addition, an intravital microscopic imaging analysis showed that the carboxyl-terminal fragment of ADAMTS13 (T2C or T5C) was capable of inhibiting the formation and elongation of platelet-decorated ultra large (UL) VWF strings and the adhesion of platelets/leukocytes on endothelium in mesenteric venules after oxidative injury. The inhibitory activity of T2C and T5C on platelet aggregation and ULVWF string formation were dependent on the presence of their surface free thiols; pretreatment of T2C and T5C or full-length ADAMTS13 with N-ethylmaleimide that reacts with free sulfhydryls abolished or significantly reduced its antithrombotic activity. CONCLUSIONS Our results demonstrate for the first time that the carboxyl terminus of ADAMTS13 has direct antithrombotic activity in a free-thiol-dependent manner. The free thiols in the carboxyl-terminal domains of ADAMTS13 may also contribute to the overall antithrombotic function of ADAMTS13 under pathophysiological conditions.
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Affiliation(s)
- Jialing Bao
- From the Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia (J.B., J.X., Y.M., X.L.Z.); The University of Pennsylvania Perelman School of Medicine, Philadelphia (X.L.Z.); and the Department of Obstetrics and Gynecology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China (J.X., X.L.Z.)
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Akiyama M, Nakayama D, Takeda S, Kokame K, Takagi J, Miyata T. Crystal structure and enzymatic activity of an ADAMTS-13 mutant with the East Asian-specific P475S polymorphism. J Thromb Haemost 2013; 11:1399-406. [PMID: 23621748 DOI: 10.1111/jth.12279] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 04/05/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND An East Asian-specific P475S polymorphism in the gene encoding ADAMTS-13 causes an approximately 16% reduction in plasma ADAMTS-13 activity. OBJECTIVES To demonstrate the impact of this dysfunctional polymorphism by characterizing the structure and activity of the P475S mutant protein. METHODS We determined the crystal structure of the P475S mutant of ADAMTS-13-DTCS (DTCS-P475S, residues 287-685) and compared it with the wild-type structure. We determined the enzymatic parameters of ADAMTS-13-MDTCS (residues 75-685) and MDTCS-P475S, and further examined the effects of denaturants and reaction temperature on their activity. We also examined the cleavage of shear-treated von Willebrand factor (VWF) by MDTCS-P475S. RESULTS MDTCS-P475S showed a reaction rate similar to that of wild-type MDTCS, but showed two-fold lower affinity for the peptidyl substrate, indicating that the Pro475-containing V-loop (residues 474-481) in the CA domain is a substrate-binding exosite. Structural analysis showed that the conformation of the V-loop was significantly different in DTCS-P475S and the wild type, where no obvious interactions of Ser475 with other residues were observed. This explains the higher susceptibility of the enzymatic activity of MDTCS-P475S to reaction environments such as denaturants and high temperature. MDTCS-P475S can moderately cleave shear-treated VWF. CONCLUSIONS We have provided structural evidence that the P475S polymorphism in ADAMTS-13 leads to increased local structural instability, resulting in lowered affinity for the substrate without changing the reaction rate. The moderate activity of ADAMTS-13-P475S for shear-treated VWF is sufficient to prevent thrombotic thrombocytopenic purpura (TTP) onset.
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Affiliation(s)
- M Akiyama
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Osaka, Japan.
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Zheng XL. Structure-function and regulation of ADAMTS-13 protease. J Thromb Haemost 2013; 11 Suppl 1:11-23. [PMID: 23809107 PMCID: PMC3713533 DOI: 10.1111/jth.12221] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Accepted: 03/03/2013] [Indexed: 12/11/2022]
Abstract
ADAMTS-13, a plasma reprolysin-like metalloprotease, cleaves von Willebrand factor (VWF). Severe deficiency of plasma ADAMTS-13 activity results in thrombotic thrombocytopenic purpura (TTP), while mild to moderate deficiencies of plasma ADAMTS-13 activity are emerging risk factors for developing myocardial and cerebral infarction, pre-eclampsia, and malignant malaria. Moreover, Adamts13(-/-) mice develop more severe inflammatory responses, leading to increased ischemia/perfusion injury and formation of atherosclerosis. Structure-function studies demonstrate that the N-terminal portion of ADAMTS-13 (MDTCS) is necessary and sufficient for proteolytic cleavage of VWF under various conditions and attenuation of arterial/venous thrombosis after oxidative injury. The more distal portion of ADAMTS-13 (TSP1 2-8 repeats and CUB domains) may function as a disulfide bond reductase to prevent an elongation of ultra-large VWF strings on activated endothelial cells and inhibit platelet adhesion/aggregation on collagen surface under flow. Remarkably, the proteolytic cleavage of VWF by ADAMTS-13 is accelerated by FVIII and platelets under fluid shear stress. A disruption of the interactions between FVIII (or platelet glycoprotein 1bα) and VWF dramatically impairs ADAMTS-13-dependent proteolysis of VWF in vitro and in vivo. These results suggest that FVIII and platelets may be physiological cofactors regulating VWF proteolysis. Finally, the structure-function and autoantibody mapping studies allow us to identify an ADAMTS-13 variant with increased specific activity but reduced inhibition by autoantibodies in patients with acquired TTP. Together, these findings provide novel insight into the mechanism of VWF proteolysis and tools for the therapy of acquired TTP and perhaps other arterial thrombotic disorders.
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Affiliation(s)
- X L Zheng
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
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Ling J, Su J, Ma Z, Ruan C. The WXXW motif in the TSR1 of ADAMTS13 is important for its secretion and proteolytic activity. Thromb Res 2013; 131:529-34. [PMID: 23683325 DOI: 10.1016/j.thromres.2013.04.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/16/2013] [Accepted: 04/19/2013] [Indexed: 11/24/2022]
Abstract
INTRODUCTION ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) is a metalloprotease enzyme that regulates the size and activity of the von Willebrand factor (VWF). ADAMTS13, like many other ADAMTSs, has a WXXW motif in its thrombospondin type 1 repeat domain (TSR1). However, the function of the WXXW motif in ADAMTSs is unclear. MATERIALS AND METHODS The constructs of wild-type (WT) and WXXW mutant (W387A) ADAMTS13 was generated by PCR site-directed mutagenesis. The secretion of the protein was quantified with western blotting methods. The binding affinity of the WT or W387A mutant ADAMTS13 with Plasma-derived human VWF (pVWF) was investigated by using enzyme linked immunosorbent assay. The Cleaving activity of the WT or W387A mutant ADAMTS13 against full length pVWF was measured under denatured conditions or shear stress. The proteolytic activity was also validated with the FRETS-VWF73 assay. RESULTS The W387A mutant was secreted less efficiently and had a reduced binding affinity for pre-denatured pVWF in comparison to WT ADAMTS13. However, both the WT and mutant ADAMTS13 interacted equally with native pVWF. The W387A mutant showed less cleaving activity against VWF under denaturing conditions, and the same result was observed when the fluorescence resonance energy transfer substrate VWF73 (FRETS-VWF73) was used as the substrate. However, under high shear stress conditions the mutant and WT ADAMTS13 were equally able to cleave VWF. CONCLUSION The WXXW motif is important for the secretion of ADAMTS13 and that it modulates the proteolytic cleavage of VWF by ADAMTS13 under denaturing conditions.
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Affiliation(s)
- Jing Ling
- Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu, China
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Preferential HLA-DRB1*11–dependent presentation of CUB2-derived peptides by ADAMTS13-pulsed dendritic cells. Blood 2013; 121:3502-10. [DOI: 10.1182/blood-2012-09-456780] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Key Points
ADAMTS13 derived peptides presented on HLA-DR; implications for acquired TTP. CUB2 domain peptide binds to risk-allele HLA-DRB1*11.
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Crawley JTB, Scully MA. Thrombotic thrombocytopenic purpura: basic pathophysiology and therapeutic strategies. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2013; 2013:292-9. [PMID: 24319194 DOI: 10.1182/asheducation-2013.1.292] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
VWF is a multimeric plasma glycoprotein that specifically recruits platelets to sites of vessel injury. VWF multimeric size is central to this function, with larger multimers being more hemostatically active. Regulation of VWF multimeric size is mediated by the plasma metalloprotease ADAMTS13 (A Disintegrin And Metalloproteinase with ThromboSpondin type 1 motifs, member 13). This enzyme can only recognize and cleave VWF when it is unraveled by rheological shear forces of the flowing blood. After the exposure of cryptic exosites, VWF recognition by ADAMTS13 involves multiple interactions that enable the protease to cleave VWF. Loss of VWF multimer size regulation caused by severe ADAMTS13 deficiency (either inherited or acquired) is associated with the microvascular thrombotic disorder thrombotic thrombocytopenic purpura (TTP). The sequelae associated with TTP are widely thought to be linked to hyperreactive circulating VWF that cause unwanted platelet aggregation in the high shear environment of the microvasculature. Diagnosis of TTP is primarily made through a combination of symptoms, analysis of plasma ADAMTS13 activity, and detection of inhibitory anti-ADAMTS13 antibodies. Current frontline treatments for TTP include plasma exchange, which serves to remove inhibitory antibodies (in acquired TTP) and provide a source of functional ADAMTS13, and steroids to treat the autoimmune component of acquired TTP. The use of anti-CD20 therapy has also exhibited encouraging results in the treatment of acquired TTP. Newer therapeutic strategies that are currently being explored or are in development include recombinant ADAMTS13, a hyperreactive ADAMTS13 variant, and anti-VWF therapy. This review discusses the basic biochemistry of VWF and ADAMTS13, their dysfunction in TTP, and therapeutic approaches for the amelioration of TTP.
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Affiliation(s)
- James T B Crawley
- 1Centre for Haematology, Imperial College London, London, United Kingdom; and
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Abstract
Abstract
The regulation of VWF multimer size is essential in preventing spontaneous microvascular platelet clumping, a central pathophysiologic finding in thrombotic thrombocytopenic purpura (TTP). In the majority of TTP patients, ADAMTS13, the principal regulator of VWF size, is severely deficient. Today, 2 forms of severe ADAMTS13 deficiency are recognized. The acquired form is caused by circulating autoantibodies inhibiting ADAMTS13 activity or increasing ADAMTS13 clearance. Pathogenic anti-ADAMTS13 Abs are mainly of the IgG class, predominantly of subclass IgG4, and inhibitory Abs recognize a defined epitope in the ADAMTS13 spacer domain. The reasons underlying the failure to maintain immunologic tolerance to ADAMTS13, however, are still poorly understood. Constitutional ADAMTS13 deficiency leading to hereditary TTP, also known as Upshaw-Schulman syndrome, is the result of homozygous or compound heterozygous ADAMTS13 gene mutations.
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Peyvandi F, Palla R, Lotta LA. Pathogenesis and treatment of acquired idiopathic thrombotic thrombocytopenic purpura. Haematologica 2012; 95:1444-7. [PMID: 20807984 DOI: 10.3324/haematol.2010.027169] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Interlandi G, Ling M, Tu AY, Chung DW, Thomas WE. Structural basis of type 2A von Willebrand disease investigated by molecular dynamics simulations and experiments. PLoS One 2012; 7:e45207. [PMID: 23110044 PMCID: PMC3479114 DOI: 10.1371/journal.pone.0045207] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/16/2012] [Indexed: 12/12/2022] Open
Abstract
The hemostatic function of von Willebrand factor is downregulated by the metalloprotease ADAMTS13, which cleaves at a unique site normally buried in the A2 domain. Exposure of the proteolytic site is induced in the wild-type by shear stress as von Willebrand factor circulates in blood. Mutations in the A2 domain, which increase its susceptibility to cleavage, cause type 2A von Willebrand disease. In this study, molecular dynamics simulations suggest that the A2 domain unfolds under tensile force progressively through a series of steps. The simulation results also indicated that three type 2A mutations in the C-terminal half of the A2 domain, L1657I, I1628T and E1638K, destabilize the native state fold of the protein. Furthermore, all three type 2A mutations lowered in silico the tensile force necessary to undock the C-terminal helix 6 from the rest of the A2 domain, the first event in the unfolding pathway. The mutations F1520A, I1651A and A1661G were also predicted by simulations to destabilize the A2 domain and facilitate exposure of the cleavage site. Recombinant A2 domain proteins were expressed and cleavage assays were performed with the wild-type and single-point mutants. All three type 2A and two of the three predicted mutations exhibited increased rate of cleavage by ADAMTS13. These results confirm that destabilization of the helix 6 in the A2 domain facilitates exposure of the cleavage site and increases the rate of cleavage by ADAMTS13.
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Affiliation(s)
- Gianluca Interlandi
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America.
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Blombäck M, Eikenboom J, Lane D, Denis C, Lillicrap D. von Willebrand disease biology. Haemophilia 2012; 18 Suppl 4:141-7. [PMID: 22726098 DOI: 10.1111/j.1365-2516.2012.02840.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- M Blombäck
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
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Abstract
Prevailing approaches to manage autoimmune thrombotic disorders, such as heparin-induced thrombocytopenia, antiphospholipid syndrome and thrombotic thrombocytopenic purpura, include immunosuppression and systemic anticoagulation, though neither provides optimal outcome for many patients. A different approach is suggested by the concurrence of autoantibodies and their antigenic targets in the absence of clinical disease, such as platelet factor 4 in heparin-induced thrombocytopenia and β(2)-glycoprotein-I (β(2)GPI) in antiphospholipid syndrome. The presence of autoantibodies in the absence of disease suggests that conformational changes or other alterations in endogenous protein autoantigens are required for recognition by pathogenic autoantibodies. In thrombotic thrombocytopenic purpura, the clinical impact of ADAMTS13 deficiency caused by autoantibodies likely depends on the balance between residual antigen, that is, enzyme activity, and demand imposed by local genesis of ultralarge multimers of von Willebrand factor. A corollary of these concepts is that disrupting platelet factor 4 and β(2)GPI conformation (or ultralarge multimer of von Willebrand factor oligomerization or function) might provide a disease-targeted approach to prevent thrombosis without systemic anticoagulation or immunosuppression. Validation of this approach requires a deeper understanding of how seemingly normal host proteins become antigenic or undergo changes that increase antibody avidity, and how they can be altered to retain adaptive functions while shedding epitopes prone to elicit harmful autoimmunity.
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