1
|
Dainese C, Valeri F, Bruno B, Borchiellini A. Anti-ADAMTS13 Autoantibodies: From Pathophysiology to Prognostic Impact-A Review for Clinicians. J Clin Med 2023; 12:5630. [PMID: 37685697 PMCID: PMC10488355 DOI: 10.3390/jcm12175630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 09/10/2023] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a fatal disease in which platelet-rich microthrombi cause end-organ ischemia and damage. TTP is caused by markedly reduced ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity. ADAMTS13 autoantibodies (autoAbs) are the major cause of immune TTP (iTTP), determining ADAMTS13 deficiency. The pathophysiology of such autoAbs as well as their prognostic role are continuous objects of scientific studies in iTTP fields. This review aims to provide clinicians with the basic information and updates on autoAbs' structure and function, how they are typically detected in the laboratory and their prognostic implications. This information could be useful in clinical practice and contribute to future research implementations on this specific topic.
Collapse
Affiliation(s)
- Cristina Dainese
- Regional Centre for Hemorrhagic and Thrombotic Diseases, AOU Città Della Salute e Della Scienza, 10126 Turin, Italy; (F.V.); (A.B.)
- Division of Hematology, AOU Città Della Salute e Della Scienza and University of Turin, 10124 Turin, Italy;
| | - Federica Valeri
- Regional Centre for Hemorrhagic and Thrombotic Diseases, AOU Città Della Salute e Della Scienza, 10126 Turin, Italy; (F.V.); (A.B.)
- Division of Hematology, AOU Città Della Salute e Della Scienza and University of Turin, 10124 Turin, Italy;
| | - Benedetto Bruno
- Division of Hematology, AOU Città Della Salute e Della Scienza and University of Turin, 10124 Turin, Italy;
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy
| | - Alessandra Borchiellini
- Regional Centre for Hemorrhagic and Thrombotic Diseases, AOU Città Della Salute e Della Scienza, 10126 Turin, Italy; (F.V.); (A.B.)
- Division of Hematology, AOU Città Della Salute e Della Scienza and University of Turin, 10124 Turin, Italy;
| |
Collapse
|
2
|
Sakai K, Miyadera H, Kubo M, Nakajima F, Matsumoto M. Overlapping ADAMTS13 peptide binding profiles of DRB1∗08:03 and DRB1∗11:01 suggest a common etiology of immune-mediated thrombotic thrombocytopenic purpura. J Thromb Haemost 2023; 21:616-628. [PMID: 36696200 DOI: 10.1016/j.jtha.2022.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/05/2022] [Accepted: 09/23/2022] [Indexed: 01/09/2023]
Abstract
BACKGROUND Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is an ultra-rare autoimmune disorder caused by autoantibodies against ADAMTS13. A strong association of DRB1∗11 with iTTP and DRB1∗11-restricted T-cell epitopes in ADAMTS13 have been reported in Europeans, whereas we previously found DRB1∗08:03 as a susceptible allele in Japanese. OBJECTIVES The limited information is available regarding a susceptible allele and its T-cell epitopes in Japanese patients with iTTP. MATERIALS AND METHODS We conducted a reanalysis on iTTP-predisposing alleles using 3 distinct Japanese control groups. Subsequently, a novel human leukocyte antigen (HLA)-peptide expression assay (MHC-density assay) was used to identify the presentation of 24 ADAMTS13-derived peptides, including the regions that were identified previously by MHC-peptidome analysis and/or T-cell assays or predicted by NetMHCIIpan-4.0, to DRB1∗08:03 and DRB1∗11:01. RESULTS We reconfirmed the strong association of DRB1∗08:03 with iTTP, as well as the absence of the secondary risk alleles and protective alleles in Japanese iTTP, which altogether reveal that the HLA association pattern is completely different between the European and Japanese iTTP. MHC-density assay found the 3 ADAMTS13-derived peptides in the spacer domain as a potential strong binder to DRB1∗08:03. Moreover, 6 peptides in the metalloprotease, spacer, sixth thrombospondin-1 repeat, and CUB domains in ADAMTS13 showed increased presentation by both DRB1∗08:03 and DRB1∗11:01. CONCLUSION Altogether, the findings of distinct HLA-DR association with iTTP across populations and the presentation of common peptides by DRB1∗08:03 and DRB1∗11:01 suggest that the same ADAMTS13-derived peptides might be presented and trigger the activation of autoreactive CD4+ T cells, leading to production of anti-ADAMTS13 autoantibodies by autoreactive B cells.
Collapse
Affiliation(s)
- Kazuya Sakai
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
| | - Hiroko Miyadera
- Department of Medical Genetics, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Masayuki Kubo
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
| | | | - Masanori Matsumoto
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan.
| |
Collapse
|
3
|
Voorberg J, Arfman T, Maillere B. Big in Japan: HLA-DRB1∗08:03 and immune thrombotic thrombocytopenic purpura. J Thromb Haemost 2023; 21:456-459. [PMID: 36858791 DOI: 10.1016/j.jtha.2022.11.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 03/03/2023]
Affiliation(s)
- Jan Voorberg
- Department of Molecular Hematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Experimental Vascular Medicine, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Tom Arfman
- Department of Molecular Hematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Bernard Maillere
- Université de Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé, SIMoS, Gif-sur-Yvette, France
| |
Collapse
|
4
|
Frontiers in pathophysiology and management of thrombotic thrombocytopenic purpura. Int J Hematol 2023; 117:331-340. [PMID: 36757521 DOI: 10.1007/s12185-023-03552-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/25/2023] [Accepted: 01/25/2023] [Indexed: 02/10/2023]
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a fatal disease in which platelet-rich microthrombi cause end-organ ischemia and damage. TTP is caused by markedly reduced ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity. Hereditary or congenital TTP (cTTP) is caused by ADAMTS13 gene mutations. In acquired or immune TTP (iTTP), ADAMTS13 activity is reduced by anti-ADAMTS13 autoantibodies. TTP is characterized by thrombocytopenia, hemolytic anemia, fever, renal dysfunction, and neuropsychiatric symptoms. Therapeutic plasma exchange (TPE) and immunosuppressive therapy are the mainstays of treatment. As untreated TTP has a high mortality rate, immediate initiation of TPE is recommended when TTP is suspected. Conventionally, corticosteroids have been used for immunosuppressive therapy. Current drug therapies include rituximab, an anti-CD20 antibody that is effective in newly diagnosed cases and refractory cases, as well as for relapse prevention, and caplacizumab, an anti- von Willebrand factor (VWF) nanobody that inhibits the binding of platelets to VWF and prevents microthrombi formation. Recombinant human ADAMTS13 is a promising treatment for cTTP. Although these therapeutic advances have improved the outcomes of TTP, early diagnosis and prompt initiation of appropriate therapy are necessary to achieve these outcomes.
Collapse
|
5
|
Cauchois R, Muller R, Lagarde M, Dignat-George F, Tellier E, Kaplanski G. Is Endothelial Activation a Critical Event in Thrombotic Thrombocytopenic Purpura? J Clin Med 2023; 12:jcm12030758. [PMID: 36769407 PMCID: PMC9918301 DOI: 10.3390/jcm12030758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/20/2023] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a severe thrombotic microangiopathy. The current pathophysiologic paradigm suggests that the ADAMTS13 deficiency leads to Ultra Large-Von Willebrand Factor multimers accumulation with generation of disseminated microthrombi. Nevertheless, the role of endothelial cells in this pathology remains an issue. In this review, we discuss the various clinical, in vitro and in vivo experimental data that support the important role of the endothelium in this pathology, suggesting that ADAMTS13 deficiency may be a necessary but not sufficient condition to induce TTP. The "second hit" model suggests that in TTP, in addition to ADAMTS13 deficiency, endogenous or exogenous factors induce endothelial activation affecting mainly microvascular cells. This leads to Weibel-Palade bodies degranulation, resulting in UL-VWF accumulation in microcirculation. This endothelial activation seems to be worsened by various amplification loops, such as the complement system, nucleosomes and free heme.
Collapse
Affiliation(s)
- Raphael Cauchois
- Aix Marseille University, Assistance Publique Hôpitaux de Marseille, INSERM, INRAE, C2VN, CHU Conception, Internal Medicine and Clinical Immunology, 13005 Marseille, France
- French Reference Center for Thrombotic Microangiopathies, 75571 Paris, France
- Correspondence:
| | - Romain Muller
- Aix Marseille University, Assistance Publique Hôpitaux de Marseille, INSERM, INRAE, C2VN, CHU Conception, Internal Medicine and Clinical Immunology, 13005 Marseille, France
| | - Marie Lagarde
- French Reference Center for Thrombotic Microangiopathies, 75571 Paris, France
- Aix Marseille University, INSERM, INRAE, C2VN, 13005 Marseille, France
| | - Françoise Dignat-George
- Aix Marseille University, Assistance Publique Hôpitaux de Marseille, INSERM, INRAE, C2VN, CHU Conception, Hematology Laboratory, 13005 Marseille, France
| | - Edwige Tellier
- French Reference Center for Thrombotic Microangiopathies, 75571 Paris, France
- Aix Marseille University, INSERM, INRAE, C2VN, 13005 Marseille, France
| | - Gilles Kaplanski
- Aix Marseille University, Assistance Publique Hôpitaux de Marseille, INSERM, INRAE, C2VN, CHU Conception, Internal Medicine and Clinical Immunology, 13005 Marseille, France
- French Reference Center for Thrombotic Microangiopathies, 75571 Paris, France
| |
Collapse
|
6
|
Alterations in B- and circulating T-follicular helper cell subsets in immune thrombotic thrombocytopenic purpura. Blood Adv 2022; 6:3792-3802. [PMID: 35507753 PMCID: PMC9631570 DOI: 10.1182/bloodadvances.2022007025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/19/2022] [Indexed: 11/20/2022] Open
Abstract
Abnormal B-cell phenotype in acute iTTP with decreased transitional and post–germinal center memory cells and increased plasmablasts. Decreased total and PD1+ circulating T-follicular helper cells and changes in B-cell CD80 expression suggest altered B- and T-cell interactions.
T follicular helper (Tfh) cells regulate development of antigen-specific B-cell immunity. We prospectively investigated B-cell and circulating Tfh (cTfh) cell subsets in 45 patients with immune thrombotic thrombocytopenic purpura (iTTP) at presentation and longitudinally after rituximab (RTX). B-cell phenotype was altered at acute iTTP presentation with decreased transitional cells and post–germinal center (post-GC) memory B cells and increased plasmablasts compared with healthy controls. A higher percentage of plasmablasts was associated with higher anti-ADAMTS13 IgG and lower ADAMTS13 antigen levels. In asymptomatic patients with ADAMTS13 relapse, there were increased naïve B cells and a global decrease in memory subsets, with a trend to increased plasmablasts. Total circulating Tfh (CD4+CXCR5+) and PD1+ Tfh cells were decreased at iTTP presentation. CD80 expression was decreased on IgD+ memory cells and double-negative memory cells in acute iTTP. At repopulation after B-cell depletion in de novo iTTP, post-GC and double-negative memory B cells were reduced compared with pre-RTX. RTX did not cause alteration in cTfh cell frequency. The subsequent kinetics of naïve, transitional, memory B cells and plasmablasts did not differ significantly between patients who went on to relapse vs those who remained in remission. In summary, acute iTTP is characterized by dysregulation of B- and cTfh cell homeostasis with depletion of post-GC memory cells and cTfh cells and increased plasmablasts. Changes in CD80 expression on B cells further suggest altered interactions with T cells.
Collapse
|
7
|
Successful preventive treatment with cyclosporine in a patient with relapsed/refractory immune-mediated thrombotic thrombocytopenic purpura: a case report and review of the literature. Int J Hematol 2022; 116:295-301. [PMID: 35274194 DOI: 10.1007/s12185-022-03319-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/24/2022] [Accepted: 02/24/2022] [Indexed: 10/18/2022]
Abstract
Although salvage therapy with rituximab is effective in some cases of immune-mediated thrombotic thrombocytopenic purpura (iTTP) refractory to standard plasma exchange (PEX) and glucocorticoid treatment or relapsed after treatment, protocols to address the subsequent high recurrence rate have not been established. We describe the use of cyclosporine (CSA) to prevent recurrence in a patient with iTTP relapse after rituximab therapy, and present a literature review. A 24-year-old woman was diagnosed with iTTP and initially received PEX and high-dose methylprednisolone therapy. However, weekly rituximab therapy was also needed for inhibitor boosting to achieve additional immunosuppression during the initial treatment. Although the patient achieved clinical remission after weekly rituximab therapy, iTTP relapsed twice when glucocorticoids were tapered, and was treated with a triplet regimen consisting of PEX, high-dose methylprednisolone, and weekly rituximab. CSA was administered along with glucocorticoids as prophylaxis against iTTP relapse. The additional CSA therapy successfully maintained iTTP remission and allowed reduction of the corticosteroid dose. Our findings demonstrate that prophylactic CSA can potentially prevent iTTP recurrence in patients with a history of multiple relapses. Data from more cases must be accumulated to establish a useful prophylactic therapy for iTTP that is refractory even to rituximab.
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Koneczny I, Yilmaz V, Lazaridis K, Tzartos J, Lenz TL, Tzartos S, Tüzün E, Leypoldt F. Common Denominators in the Immunobiology of IgG4 Autoimmune Diseases: What Do Glomerulonephritis, Pemphigus Vulgaris, Myasthenia Gravis, Thrombotic Thrombocytopenic Purpura and Autoimmune Encephalitis Have in Common? Front Immunol 2021; 11:605214. [PMID: 33584677 PMCID: PMC7878376 DOI: 10.3389/fimmu.2020.605214] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 12/08/2020] [Indexed: 12/20/2022] Open
Abstract
IgG4 autoimmune diseases (IgG4-AID) are an emerging group of autoimmune diseases that are caused by pathogenic autoantibodies of the IgG4 subclass. It has only recently been appreciated, that members of this group share relevant immunobiological and therapeutic aspects even though different antigens, tissues and organs are affected: glomerulonephritis (kidney), pemphigus vulgaris (skin), thrombotic thrombocytopenic purpura (hematologic system) muscle-specific kinase (MuSK) in myasthenia gravis (peripheral nervous system) and autoimmune encephalitis (central nervous system) to give some examples. In all these diseases, patients’ IgG4 subclass autoantibodies block protein-protein interactions instead of causing complement mediated tissue injury, patients respond favorably to rituximab and share a genetic predisposition: at least five HLA class II genes have been reported in individual studies to be associated with several different IgG4-AID. This suggests a role for the HLA class II region and specifically the DRβ1 chain for aberrant priming of autoreactive T-cells toward a chronic immune response skewed toward the production of IgG4 subclass autoantibodies. The aim of this review is to provide an update on findings arguing for a common pathogenic mechanism in IgG4-AID in general and to provide hypotheses about the role of distinct HLA haplotypes, T-cells and cytokines in IgG4-AID.
Collapse
Affiliation(s)
- Inga Koneczny
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Vuslat Yilmaz
- Department of Neuroscience, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Konstantinos Lazaridis
- Department of Immunology, Laboratory of Immunology, Hellenic Pasteur Institute, Athens, Greece
| | - John Tzartos
- Tzartos NeuroDiagnostics, Athens, Greece.,1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Tobias L Lenz
- Research Group for Evolutionary Immunogenomics, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Socrates Tzartos
- Tzartos NeuroDiagnostics, Athens, Greece.,Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Erdem Tüzün
- Department of Neuroscience, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Frank Leypoldt
- Neuroimmunology, Institute of Clinical Chemistry and Department of Neurology, Medical Faculty, Christian-Albrechts-University Kiel, Kiel, Germany
| |
Collapse
|
10
|
Wirtz MR, van den Brink DP, Roelofs JJTH, Goslings JC, Juffermans NP. Therapeutic application of recombinant human ADAMTS-13 improves shock reversal and coagulation status in a trauma hemorrhage and transfusion rat model. Intensive Care Med Exp 2020; 8:42. [PMID: 33336308 PMCID: PMC7746419 DOI: 10.1186/s40635-020-00328-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 12/29/2022] Open
Abstract
INTRODUCTION In hemorrhaging trauma patients, the endothelium is activated, resulting in excessive endothelial synthesis of von Willebrand Factor (vWF), which may enhance micro-thrombi formation, resulting in obstruction of the microcirculation and endothelial injury, aggravating bleeding, as well as contributing to organ failure. Under normal conditions, vWF is cleaved by the metalloprotease ADAMTS-13. After trauma, ADAMTS-13 levels are reduced. OBJECTIVES To assess whether recombinant human ADAMTS-13 inhibits endothelial injury and organ failure in a rat trauma-transfusion model. METHODS Blood products were prepared from syngeneic rat blood according to blood bank standards. Polytrauma was induced in rats by crush injury to the intestines and liver and by fracture of the femur. The rats were hemorrhaged until a mean arterial pressure (MAP) of 40 mmHg was reached. Rats were randomized to receive transfusion of RBCs, FFPs, and platelets in a 1:1:1 ratio to achieve a MAP of 70 mmHg, with or without the addition of ADAMTS-13 (50 μg/kg). Blood samples were assessed for biochemistry and rotational thromboelastometry (ROTEM). Syndecan-1 and VE-cadherin levels were measured as a reflection of endothelial integrity. The amount of leakage of dextran-FITC from the vascular system to the parenchyma in lungs was quantified. To assess inflammation, IL-6 and IL-8 levels were determined. Organ damage was assessed by histopathology. RESULTS All rats were severely shocked, with no significant differences in shock parameters between groups. Rats treated with ADAMTS-13 showed signs of a more effective shock reversal (higher blood pressure, lower lactate levels) compared to controls. Also, ROTEM parameters of clot formation in rats receiving ADAMTS-13 improved compared to controls, which was mainly platelet-dependent. Syndecan-1 levels relative to baseline trended to be lower in ADAMTS-13 treated rats compared to controls (107 vs 149%, p = 0.08). ADAMTS-13 reduced albuminuria (1.7 vs 4.4 g/L, p < 0.01) and organ-specific inflammation (pulmonary IL-6 243 vs 369 pg/mL, p = 0.08; splenic IL-6 253 vs 307, p = 0.03) compared to controls, but did not improve histopathological scores. CONCLUSIONS The use of ADAMTS-13 in a rat trauma-transfusion model improves parameters of shock, platelet-driven coagulation, endothelial damage, and organ inflammation. These results suggest that ADAMTS-13 is important in mediating outcome of trauma. Whether ADAMTS-13 can be used as a therapeutic adjunct to treat bleeding trauma patients remains to be determined.
Collapse
Affiliation(s)
- Mathijs R Wirtz
- Department of Intensive Care Medicine, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands. .,Laboratory of Experimental Intensive Care and Anesthesiology, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands. .,Department of Trauma Surgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands.
| | - Daan P van den Brink
- Department of Intensive Care Medicine, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands.,Department of Trauma Surgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
| | - Joris J T H Roelofs
- Department of Pathology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
| | - J Carel Goslings
- Department of Trauma Surgery, Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands
| | - Nicole P Juffermans
- Department of Intensive Care Medicine, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands.,Laboratory of Experimental Intensive Care and Anesthesiology, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
| |
Collapse
|
11
|
Koşaloğlu-Yalçın Z, Sidney J, Chronister W, Peters B, Sette A. Comparison of HLA ligand elution data and binding predictions reveals varying prediction performance for the multiple motifs recognized by HLA-DQ2.5. Immunology 2020; 162:235-247. [PMID: 33064841 PMCID: PMC7808151 DOI: 10.1111/imm.13279] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/06/2020] [Accepted: 10/07/2020] [Indexed: 12/02/2022] Open
Abstract
Binding prediction tools are commonly used to identify peptides presented on MHC class II molecules. Recently, a wealth of data in the form of naturally eluted ligands has become available and discrepancies between ligand elution data and binding predictions have been reported. Quantitative metrics for such comparisons are currently lacking. In this study, we assessed how efficiently MHC class II binding predictions can identify naturally eluted peptides, and investigated instances with discrepancies between the two methods in detail. We found that, in general, MHC class II eluted ligands are predicted to bind to their reported restriction element with high affinity. But, for several studies reporting an increased number of ligands that were not predicted to bind, we found that the reported MHC restriction was ambiguous. Additional analyses determined that most of the ligands predicted to not bind, are predicted to bind other co‐expressed MHC class II molecules. For selected alleles, we addressed discrepancies between elution data and binding predictions by experimental measurements and found that predicted and measured affinities correlate well. For DQA1*05:01/DQB1*02:01 (DQ2.5) however, binding predictions did miss several peptides that were determined experimentally to be binders. For these peptides and several known DQ2.5 binders, we determined key residues for conferring DQ2.5 binding capacity, which revealed that DQ2.5 utilizes two different binding motifs, of which only one is predicted effectively. These findings have important implications for the interpretation of ligand elution data and for the improvement of MHC class II binding predictions.
Collapse
Affiliation(s)
| | - John Sidney
- La Jolla Institute for Immunology, La Jolla, CA, USA
| | | | - Bjoern Peters
- La Jolla Institute for Immunology, La Jolla, CA, USA.,Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Alessandro Sette
- La Jolla Institute for Immunology, La Jolla, CA, USA.,Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| |
Collapse
|
12
|
Joly BS, Loiseau P, Darmon M, Leblanc T, Chambost H, Fouyssac F, Guigonis V, Harambat J, Stepanian A, Coppo P, Veyradier A. HLA-DRB1*11 is a strong risk factor for acquired thrombotic thrombocytopenic purpura in children. Haematologica 2020; 105:e531. [PMID: 33054098 PMCID: PMC7556652 DOI: 10.3324/haematol.2019.241968] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Bérangère S. Joly
- Service d’Hématologie Biologique, Hôpital Lariboisière and EA3518, Institut de Recherche Saint Louis, Hôpital Saint-Louis, AP-HP. Nord, Université de Paris, Paris
- French Reference Center for Thrombotic Microangiopathies, Hôpital Saint Antoine, AP-HP.Sorbonne Université, Paris
| | - Pascale Loiseau
- Laboratoire d'Immunologie et d'Histocompatibilité, Hôpital Saint-Louis, AP-HP.Nord, Université de Paris, Paris
| | - Michael Darmon
- Service de Réanimation Médicale, Hôpital Saint-Louis, AP-HP Nord, Université de Paris, Paris
| | - Thierry Leblanc
- Service d’Hématologie Pédiatrique, Hôpital Robert Debré, AP-HP.Nord, Université de Paris, Paris
| | - Hervé Chambost
- APHM, Service d’Hématologie, Immunologie, Oncologie et Pédiatrique, Hôpital de la Timone Enfants & Aix Marseille Université, INSERM, INRA, C2VN, Marseille
| | - Fanny Fouyssac
- Service d’Hémato-Oncologie Pédiatrique, Hôpital de Brabois, CHU de Nancy, Vandoeuvre-les- Nancy
| | - Vincent Guigonis
- Service de Pédiatrie, Hôpital de la Mère et de l’Enfant, CHU de Limoges, Limoges
| | - Jérôme Harambat
- Service de Pédiatrie, Hôpital Pellegrin-Enfants, CHU de Bordeaux, Université de Bordeaux, Bordeaux
| | - Alain Stepanian
- Service d’Hématologie Biologique, Hôpital Lariboisière and EA3518, Institut de Recherche Saint Louis, Hôpital Saint-Louis, AP-HP. Nord, Université de Paris, Paris
- French Reference Center for Thrombotic Microangiopathies, Hôpital Saint Antoine, AP-HP.Sorbonne Université, Paris
| | - Paul Coppo
- French Reference Center for Thrombotic Microangiopathies, Hôpital Saint Antoine, AP-HP.Sorbonne Université, Paris
- Service d’Hématologie, Hôpital Saint Antoine, AP-HP Sorbonne Université, Paris, France
| | - Agnès Veyradier
- Service d’Hématologie Biologique, Hôpital Lariboisière and EA3518, Institut de Recherche Saint Louis, Hôpital Saint-Louis, AP-HP. Nord, Université de Paris, Paris
- French Reference Center for Thrombotic Microangiopathies, Hôpital Saint Antoine, AP-HP.Sorbonne Université, Paris
| |
Collapse
|
13
|
HLA loci predisposing to immune TTP in Japanese: potential role of the shared ADAMTS13 peptide bound to different HLA-DR. Blood 2020; 135:2413-2419. [DOI: 10.1182/blood.2020005395] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022] Open
Abstract
Abstract
Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare autoimmune disorder caused by neutralizing anti-ADAMTS13 autoantibodies. In white individuals, HLA allele DRB1*11 is a predisposing factor for iTTP, whereas DRB1*04 is a protective factor. However, the role of HLA in Asians is unclear. In this study, we analyzed 10 HLA loci using next-generation sequencing in 52 Japanese patients with iTTP, and the allele frequency in the iTTP group was compared with that in a Japanese control group. We identified the following HLA alleles as predisposing factors for iTTP in the Japanese population: DRB1*08:03 (odds ratio [OR], 3.06; corrected P [Pc] = .005), DRB3/4/5*blank (OR, 2.3; Pc = .007), DQA1*01:03 (OR, 2.25; Pc = .006), and DQB1*06:01 (OR,: 2.41; Pc = .003). The estimated haplotype consisting of these 4 alleles was significantly more frequent in the iTTP group than in the control group (30.8% vs 6.0%; Pc < .001). DRB1*15:01 and DRB5*01:01 were weak protective factors for iTTP (OR, 0.23; Pc = .076; and OR, 0.23, Pc = .034, respectively). On the other hand, DRB1*11 and DRB1*04 were not associated with iTTP in the Japanese. These findings indicated that predisposing and protective factors for iTTP differ between Japanese and white individuals. HLA-DR molecules encoded by DRB1*08:03 and DRB1*11:01 have different peptide-binding motifs, but interestingly, bound to the shared ADAMTS13 peptide in an in silico prediction model.
Collapse
|
14
|
Sinkovits G, Szilágyi Á, Farkas P, Inotai D, Szilvási A, Tordai A, Rázsó K, Réti M, Prohászka Z. Concentration and Subclass Distribution of Anti-ADAMTS13 IgG Autoantibodies in Different Stages of Acquired Idiopathic Thrombotic Thrombocytopenic Purpura. Front Immunol 2018; 9:1646. [PMID: 30061898 PMCID: PMC6054987 DOI: 10.3389/fimmu.2018.01646] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/04/2018] [Indexed: 12/14/2022] Open
Abstract
Background The acquired form of idiopathic thrombotic thrombocytopenic purpura (TTP) is an autoimmune disease, in which the underlying deficiency of the ADAMTS13 protease is caused by autoantibodies, predominantly of the IgG isotype. Certain HLA-DR-DQ haplotypes were associated with the risk of developing TTP. Objectives To investigate the development of the ADAMTS13-specific antibody response during the course of the disease, we analyzed the concentration, subclass distribution, and inhibitory potential of anti-ADAMTS13 IgG autoantibodies in samples of TTP patients drawn during the first acute phase, in remission, and during relapse. Additionally, we compared the anti-ADAMTS13 IgG levels between patients carrying and not carrying risk and protective HLA-DR-DQ haplotypes. Patients and Methods We determined the anti-ADAMTS13 IgG concentration and subclass distribution in 101 antibody-positive samples of 81 acquired TTP patients by ELISA methods. The presence and semi-quantitative amount of anti-ADAMTS13 inhibitors were determined in 97 of 100 deficient samples, and the specific inhibitory potential of anti-ADAMTS13 autoantibodies was determined in 49 selected samples, by mixing ADAMTS13-activity assays. HLA-DR-DQ typing and haplotype prediction were performed in 70 of the above patients. Results We found that IgG1 and IgG4 were the predominant subclasses, present in almost all samples. While IgG1 was the dominant subclass in almost half of the samples taken during the first acute episode, IgG4 was dominant in all samples taken during or following a relapse. The inhibitory potential of the samples correlated with levels of the IgG4 subclass. Anti-ADAMTS13 antibodies of IgG4-dominant samples had higher specific inhibitory potentials than IgG1-dominant samples, independently of disease stage. Interestingly, we found that patients carrying the protective DR7-DQ2 and DR13-DQ6 haplotypes had higher anti-ADAMTS13 IgG levels. Conclusion Our results indicate that IgG4 becomes the dominant subtype at some point of the disease course, apparently before the first relapse, parallel to the increase in inhibitory potential of the anti-ADAMTS13 autoantibodies. Furthermore, we found an association between the genetic background and the antibody response in TTP.
Collapse
Affiliation(s)
- György Sinkovits
- Research Laboratory, 3rd Department of Internal Medicine and MTA-SE Research Group of Immunology and Hematology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Ágnes Szilágyi
- Research Laboratory, 3rd Department of Internal Medicine and MTA-SE Research Group of Immunology and Hematology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Péter Farkas
- 3rd Department of Internal Medicine, Semmelweis University, Budapest, Hungary
| | - Dóra Inotai
- Laboratory of Transplantation Immunogenetics, Hungarian National Blood Transfusion Service, Budapest, Hungary
| | - Anikó Szilvási
- Laboratory of Transplantation Immunogenetics, Hungarian National Blood Transfusion Service, Budapest, Hungary
| | - Attila Tordai
- Department of Pathophysiology, Semmelweis University, Budapest, Hungary
| | - Katalin Rázsó
- Division of Haematology, Deptartment of Internal Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Marienn Réti
- Department of Haematology and Stem Cell Transplantation, Central Hospital of Southern Pest, National Institute of Haematology and Infectious Diseases, Budapest, Hungary
| | - Zoltán Prohászka
- Research Laboratory, 3rd Department of Internal Medicine and MTA-SE Research Group of Immunology and Hematology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
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.
Collapse
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
| |
Collapse
|
17
|
Hrdinová J, Verbij FC, Kaijen PHP, Hartholt RB, van Alphen F, Lardy N, Ten Brinke A, Vanhoorelbeke K, Hindocha PJ, De Groot AS, Meijer AB, Voorberg J, Peyron I. Mass spectrometry-assisted identification of ADAMTS13-derived peptides presented on HLA-DR and HLA-DQ. Haematologica 2018; 103:1083-1092. [PMID: 29567779 PMCID: PMC6058777 DOI: 10.3324/haematol.2017.179119] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 03/14/2018] [Indexed: 12/21/2022] Open
Abstract
Formation of microthrombi is a hallmark of acquired thrombotic thrombocytopenic purpura. These microthrombi originate from insufficient processing of ultra large von Willebrand factor multimers by ADAMTS13 due to the development of anti-ADAMTS13 autoantibodies. Several studies have identified the major histocompatibility complex class II alleles HLA-DRB1*11, HLA-DQB1*03 and HLA-DQB1*02:02 as risk factors for acquired thrombotic thrombocytopenic purpura development. Previous research in our department indicated that ADAMTS13 CUB2 domain-derived peptides FINVAPHAR and LIRDTHSLR are presented on HLA-DRB1*11 and HLA-DRB1*03, respectively. Here, we describe the repertoire of ADAMTS13 peptides presented on HLA-DQ. In parallel, the repertoire of ADAMTS13-derived peptides presented on HLA-DR was monitored. Using HLA-DR- and HLA-DQ-specific antibodies, we purified HLA/peptide complexes from ADAMTS13-pulsed monocyte-derived dendritic cells. Using this approach, we identified ADAMTS13-derived peptides presented on HLA-DR for all 9 samples analyzed; ADAMTS13-derived peptides presented on HLA-DQ were identified in 4 out of 9 samples. We were able to confirm the presentation of the CUB2 domain-derived peptides FINVAPHAR and LIRDTHSLR on HLA-DR. In total, 12 different core-peptide sequences were identified on HLA-DR and 8 on HLA-DQ. For HLA-DR11, several potential new core-peptides were found; 4 novel core-peptides were exclusively identified on HLA-DQ. Furthermore, an in silico analysis was performed using the EpiMatrix and JanusMatrix tools to evaluate the eluted peptides, in the context of HLA-DR, for putative effector or regulatory T-cell responses at the population level. The results from this study provide a basis for the identification of immuno-dominant epitopes on ADAMTS13 involved in the onset of acquired thrombotic thrombocytopenic purpura.
Collapse
Affiliation(s)
- Johana Hrdinová
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Fabian C Verbij
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Paul H P Kaijen
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Robin B Hartholt
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Floris van Alphen
- Department of Research Facilities, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Neubury Lardy
- Department of Immunogenetics, Sanquin, Amsterdam, the Netherlands
| | - Anja Ten Brinke
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Belgium
| | | | - Anne S De Groot
- EpiVax Inc., Providence, RI, USA.,Institute for Immunology and Informatics, University of Rhode Island, Providence, RI, USA
| | - Alexander B Meijer
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands.,Department of Research Facilities, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands.,Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, the Netherlands
| | - Jan Voorberg
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands .,Department of Experimental Vascular Medicine, Academic Medical Center, Amsterdam, the Netherlands
| | - Ivan Peyron
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, the Netherlands
| |
Collapse
|
18
|
Roose E, Schelpe AS, Joly BS, Peetermans M, Verhamme P, Voorberg J, Greinacher A, Deckmyn H, De Meyer SF, Coppo P, Veyradier A, Vanhoorelbeke K. An open conformation of ADAMTS-13 is a hallmark of acute acquired thrombotic thrombocytopenic purpura. J Thromb Haemost 2018; 16:378-388. [PMID: 29222940 DOI: 10.1111/jth.13922] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Indexed: 12/20/2022]
Abstract
Essentials Conformational changes in ADAMTS-13 are part of its mode-of-action. The murine anti-ADAMTS-13 antibody 1C4 discriminates between folded and open ADAMTS-13. ADAMTS-13 conformation is open in acute acquired thrombotic thrombocytopenic purpura (TTP). Our study forms an important basis to fully elucidate the pathophysiology of TTP. SUMMARY Background Acquired thrombotic thrombocytopenic purpura (aTTP) is an autoimmune disorder characterized by absent ADAMTS-13 activity and the presence of anti-ADAMTS-13 autoantibodies. Recently, it was shown that ADAMTS-13 adopts a folded or an open conformation. Objectives As conformational changes in self-antigens play a role in the pathophysiology of different autoimmune diseases, we hypothesized that the conformation of ADAMTS-13 changes during acute aTTP. Methods Antibodies recognizing cryptic epitopes in the spacer domain were generated. Next, the conformation of ADAMTS-13 in 40 healthy donors (HDs), 99 aTTP patients (63 in the acute phase versus 36 in remission), 12 hemolytic-uremic syndrome (HUS) patients and 63 sepsis patients was determined with ELISA. Results The antibody 1C4 recognizes a cryptic epitope in ADAMTS-13. Therefore, we were able to discriminate between a folded and an open ADAMTS-13 conformation. We showed that ADAMTS-13 in HDs does not bind to 1C4, indicating that ADAMTS-13 circulates in a folded conformation. Similar results were obtained for HUS and sepsis patients. In contrast, ADAMTS-13 of acute aTTP patients bound to 1C4 in 92% of the cases, whereas, in most cases, this binding was abolished during remission, showing that the conformation of ADAMTS-13 is open during an acute aTTP episode. Conclusions Our study shows that, besides absent ADAMTS-13 activity and the presence of anti-ADAMTS-13 autoantibodies, an open ADAMTS-13 conformation is also a hallmark of acute aTTP. Demonstrating this altered ADAMTS-13 conformation in acute aTTP will help to further unravel the pathophysiology of aTTP and lead to improved therapy and diagnosis.
Collapse
Affiliation(s)
- E Roose
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - A S Schelpe
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - B S Joly
- Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut Universitaire d'Hématologie, Hôpital Saint Louis, Université Paris Diderot, Paris, France
| | - M Peetermans
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - P Verhamme
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - J Voorberg
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
| | - A Greinacher
- Institute for Immunology and Transfusion Medicine, University Medical Center, Greifswald, Germany
| | - H Deckmyn
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - S F De Meyer
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - P Coppo
- Département d'hématologie clinique, Hôpital Saint Antoine, AP-HP and Université Pierre et Marie Curie, Paris, France
| | - A Veyradier
- Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut Universitaire d'Hématologie, Hôpital Saint Louis, Université Paris Diderot, Paris, France
| | - K Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| |
Collapse
|
19
|
Pathophysiology of thrombotic thrombocytopenic purpura. Blood 2017; 130:1181-1188. [PMID: 28768626 DOI: 10.1182/blood-2017-04-636431] [Citation(s) in RCA: 163] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/27/2017] [Indexed: 01/29/2023] Open
Abstract
The discovery of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, member 13 (ADAMTS13) revolutionized our approach to thrombotic thrombocytopenic purpura (TTP). Inherited or acquired ADAMTS13 deficiency allows the unrestrained growth of microthrombi that are composed of von Willebrand factor and platelets, which account for the thrombocytopenia, hemolytic anemia, schistocytes, and tissue injury that characterize TTP. Most patients with acquired TTP respond to a combination of plasma exchange and rituximab, but some die or acquire irreversible neurological deficits before they can respond, and relapses can occur unpredictably. However, knowledge of the pathophysiology of TTP has inspired new ways to prevent early deaths by targeting autoantibody production, replenishing ADAMTS13, and blocking microvascular thrombosis despite persistent ADAMTS13 deficiency. In addition, monitoring ADAMTS13 has the potential to identify patients who are at risk of relapse in time for preventive therapy.
Collapse
|
20
|
Gilardin L, Delignat S, Peyron I, Ing M, Lone YC, Gangadharan B, Michard B, Kherabi Y, Sharma M, Pashov A, Latouche JB, Hamieh M, Toutirais O, Loiseau P, Galicier L, Veyradier A, Kaveri S, Maillère B, Coppo P, Lacroix-Desmazes S. The ADAMTS13 1239-1253 peptide is a dominant HLA-DR1-restricted CD4 + T-cell epitope. Haematologica 2017; 102:1833-1841. [PMID: 28751567 PMCID: PMC5664387 DOI: 10.3324/haematol.2015.136671] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 07/21/2017] [Indexed: 12/14/2022] Open
Abstract
Acquired thrombotic thrombocytopenic purpura is a rare and severe disease characterized by auto-antibodies directed against “A Disintegrin And Metalloproteinase with Thrombospondin type 1 repeats, 13th member" (ADAMTS13), a plasma protein involved in hemostasis. Involvement of CD4+ T cells in the pathogenesis of the disease is suggested by the IgG isotype of the antibodies. However, the nature of the CD4+ T-cell epitopes remains poorly characterized. Here, we determined the HLA-DR-restricted CD4+ T-cell epitopes of ADAMTS13. Candidate T-cell epitopes were predicted in silico and binding affinities were confirmed in competitive enzyme-linked immunosorbent assays. ADAMTS13-reactive CD4+ T-cell hybridomas were generated following immunization of HLA-DR1 transgenic mice (Sure-L1 strain) and used to screen the candidate epitopes. We identified the ADAMTS131239–1253 peptide as the single immunodominant HLA-DR1-restricted CD4+ T-cell epitope. This peptide is located in the CUB2 domain of ADAMTS13. It was processed by dendritic cells, stimulated CD4+ T cells from Sure-L1 mice and was recognized by CD4+ T cells from an HLA-DR1-positive patient with acute thrombotic thrombocytopenic purpura. Interestingly, the ADAMTS131239–1253 peptide demonstrated promiscuity towards HLA-DR11 and HLA-DR15. Our work paves the way towards the characterization of the ADAMTS13-specific CD4+ T-cell response in patients with thrombotic thrombocytopenic purpura using ADAMTS131239–1253-loaded HLA-DR tetramers.
Collapse
Affiliation(s)
- Laurent Gilardin
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France .,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Centre National de Référence sur les Microangiopathies Thrombotiques, Hôpital Saint Antoine, AP-HP, Paris, France
| | - Sandrine Delignat
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Ivan Peyron
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Mathieu Ing
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Yu-Chun Lone
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1014, Hôpital Paul Brousse, Villejuif, France
| | - Bagirath Gangadharan
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Baptiste Michard
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Yousra Kherabi
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Meenu Sharma
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France
| | - Anastas Pashov
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Department of Immunology, Institute of Microbiology, BAS, Sofia, Bulgaria
| | | | - Mohamad Hamieh
- Laboratoire de Génétique Moléculaire, CHU CH.NICOLLE, Rouen, France
| | | | - Pascale Loiseau
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint-Louis, AP-HP, Paris, France
| | - Lionel Galicier
- Département d'Immunologie Clinique, Hôpital Saint-Louis, AP-HP, Paris, France
| | - Agnès Veyradier
- Service d'Hématologie Biologique, Hôpital Lariboisière, AP-HP, Paris, France
| | - Srini Kaveri
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,International Associated Laboratory IMPACT (INSERM, France-Indian Council of Medical Research, India), National Institute of Immunohaematology, Mumbai, India
| | - Bernard Maillère
- Institute of Biology and Technologies, SIMOPRO, Labex LERMIT, Labex VRI, Commissariat à l'énergie Atomique (CEA) Saclay, Gif sur Yvette, France
| | - Paul Coppo
- Centre National de Référence sur les Microangiopathies Thrombotiques, Hôpital Saint Antoine, AP-HP, Paris, France.,Service d'Hématologie, Hôpital Saint Antoine, AP-HP, Paris, France
| | - Sébastien Lacroix-Desmazes
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche en Santé (UMR S) 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie-Paris 6, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,Université Paris Descartes - Paris 5, UMR S 1138, Centre de Recherche des Cordeliers, Equipe Immunopathology and Therapeutic Immunointervention, Paris, France.,International Associated Laboratory IMPACT (INSERM, France-Indian Council of Medical Research, India), National Institute of Immunohaematology, Mumbai, India
| |
Collapse
|
21
|
Ludwig RJ, Vanhoorelbeke K, Leypoldt F, Kaya Z, Bieber K, McLachlan SM, Komorowski L, Luo J, Cabral-Marques O, Hammers CM, Lindstrom JM, Lamprecht P, Fischer A, Riemekasten G, Tersteeg C, Sondermann P, Rapoport B, Wandinger KP, Probst C, El Beidaq A, Schmidt E, Verkman A, Manz RA, Nimmerjahn F. Mechanisms of Autoantibody-Induced Pathology. Front Immunol 2017; 8:603. [PMID: 28620373 PMCID: PMC5449453 DOI: 10.3389/fimmu.2017.00603] [Citation(s) in RCA: 305] [Impact Index Per Article: 43.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 05/08/2017] [Indexed: 12/22/2022] Open
Abstract
Autoantibodies are frequently observed in healthy individuals. In a minority of these individuals, they lead to manifestation of autoimmune diseases, such as rheumatoid arthritis or Graves' disease. Overall, more than 2.5% of the population is affected by autoantibody-driven autoimmune disease. Pathways leading to autoantibody-induced pathology greatly differ among different diseases, and autoantibodies directed against the same antigen, depending on the targeted epitope, can have diverse effects. To foster knowledge in autoantibody-induced pathology and to encourage development of urgently needed novel therapeutic strategies, we here categorized autoantibodies according to their effects. According to our algorithm, autoantibodies can be classified into the following categories: (1) mimic receptor stimulation, (2) blocking of neural transmission, (3) induction of altered signaling, triggering uncontrolled (4) microthrombosis, (5) cell lysis, (6) neutrophil activation, and (7) induction of inflammation. These mechanisms in relation to disease, as well as principles of autoantibody generation and detection, are reviewed herein.
Collapse
Affiliation(s)
- Ralf J. Ludwig
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Frank Leypoldt
- Neuroimmunology, Institute of Clinical Chemistry, University Hospital Schleswig-Holstein, Kiel, Germany
- Neuroimmunology, Institute of Clinical Chemistry, University Hospital Schleswig-Holstein, Lübeck, Germany
- Department of Neurology, University of Kiel, Kiel, Germany
| | - Ziya Kaya
- Department of Internal Medicine III, University of Heidelberg, Heidelberg, Germany
| | - Katja Bieber
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Sandra M. McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, CA, United States
| | - Lars Komorowski
- Institute for Experimental Immunology, Affiliated to Euroimmun AG, Lübeck, Germany
| | - Jie Luo
- Department of Neuroscience, University of Pennsylvania Medical School, Philadelphia, PA, United States
| | | | | | - Jon M. Lindstrom
- Department of Neuroscience, University of Pennsylvania Medical School, Philadelphia, PA, United States
| | - Peter Lamprecht
- Department of Rheumatology, University of Lübeck, Lübeck, Germany
| | - Andrea Fischer
- Department of Internal Medicine III, University of Heidelberg, Heidelberg, Germany
| | | | - Claudia Tersteeg
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | | | - Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, CA, United States
| | - Klaus-Peter Wandinger
- Department of Neurology, Institute of Clinical Chemistry, University Medical-Centre Schleswig-Holstein, Lübeck, Germany
| | - Christian Probst
- Institute for Experimental Immunology, Affiliated to Euroimmun AG, Lübeck, Germany
| | - Asmaa El Beidaq
- Institute for Systemic Inflammation Research, University of Lübeck, Lübeck, Germany
| | - Enno Schmidt
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Alan Verkman
- Department of Medicine, University of California, San Francisco, CA, United States
- Department of Physiology, University of California, San Francisco, CA, United States
| | - Rudolf A. Manz
- Institute for Systemic Inflammation Research, University of Lübeck, Lübeck, Germany
| | - Falk Nimmerjahn
- Department of Biology, Institute of Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
22
|
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.
Collapse
|
23
|
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.
Collapse
|
24
|
Mancini I, Ricaño-Ponce I, Pappalardo E, Cairo A, Gorski MM, Casoli G, Ferrari B, Alberti M, Mikovic D, Noris M, Wijmenga C, Peyvandi F. Immunochip analysis identifies novel susceptibility loci in the human leukocyte antigen region for acquired thrombotic thrombocytopenic purpura. J Thromb Haemost 2016; 14:2356-2367. [PMID: 27762046 DOI: 10.1111/jth.13548] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 07/28/2016] [Indexed: 12/11/2022]
Abstract
Essentials Genetic predisposition to acquired thrombotic thrombocytopenic purpura (aTTP) is mainly unknown. Genetic risk factors for aTTP were studied by Immunochip analysis and replication study. Human leukocyte antigen (HLA) variant rs6903608 conferred a 2.5-fold higher risk of developing aTTP. rs6903608 and HLA-DQB1*05:03 may explain most of the HLA association signal in aTTP. Click to hear Dr Cataland's presentation on acquired thrombotic thrombocytopenic purpura SUMMARY: Background Acquired thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy associated with the development of autoantibodies against the von Willebrand factor-cleaving protease ADAMTS-13. Similarly to what has been found for other autoimmune disorders, there is evidence of a genetic contribution, including the association of the human leukocyte antigen (HLA) class II complex with disease risk. Objective To identify novel genetic risk factors in acquired TTP. Patients/Methods We undertook a case-control genetic association study in 190 European-origin TTP patients and 1255 Italian healthy controls by using the Illumina Immunochip. Replication analysis in 88 Italian cases and 456 controls was performed with single-nucleotide polymorphism (SNP) TaqMan assays. Results and conclusion We identified one common variant (rs6903608) located within the HLA class II locus that was independently associated with acquired TTP at genome-wide significance and conferred a 2.6-fold increased risk of developing a TTP episode (95% confidence interval [CI] 2.02-3.27, P = 1.64 × 10-14 ). We also found five non-HLA variants mapping to chromosomes 2, 6, 8 and X that were suggestively associated with the disease: rs9490550, rs115265285, rs5927472, rs7823314, and rs1334768 (nominal P-values ranging from 1.59 × 10-5 to 7.60 × 10-5 ). Replication analysis confirmed the association of HLA variant rs6903608 with acquired TTP (pooled P = 3.95 × 10-19 ). Imputation of classic HLA genes followed by stepwise conditional analysis revealed that the combination of rs6903608 and HLA-DQB1*05:03 may explain most of the HLA association signal in acquired TTP. Our results refined the association of the HLA class II locus with acquired TTP, confirming its importance in the etiology of this autoimmune disease.
Collapse
Affiliation(s)
- I Mancini
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, Milan, Italy
| | - I Ricaño-Ponce
- Genetics Department, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - E Pappalardo
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, Milan, Italy
| | - A Cairo
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - M M Gorski
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, Milan, Italy
| | - G Casoli
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - B Ferrari
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - M Alberti
- IRCCS - Istituto di Ricerche Farmacologiche 'Mario Negri', Clinical Research Center for Rare Diseases, Aldo e Cele Daccò, Bergamo, Italy
| | - D Mikovic
- Hemostasis Department and Hemophilia Center, Blood Transfusion Institute of Serbia, Belgrade, Serbia
| | - M Noris
- IRCCS - Istituto di Ricerche Farmacologiche 'Mario Negri', Clinical Research Center for Rare Diseases, Aldo e Cele Daccò, Bergamo, Italy
| | - C Wijmenga
- Genetics Department, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - F Peyvandi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, Milan, Italy
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| |
Collapse
|
25
|
Sinkovits G, Szilágyi Á, Farkas P, Inotai D, Szilvási A, Tordai A, Rázsó K, Réti M, Prohászka Z. The role of human leukocyte antigen DRB1-DQB1 haplotypes in the susceptibility to acquired idiopathic thrombotic thrombocytopenic purpura. Hum Immunol 2016; 78:80-87. [PMID: 27866840 DOI: 10.1016/j.humimm.2016.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 11/11/2016] [Accepted: 11/16/2016] [Indexed: 12/15/2022]
Abstract
The acquired form of idiopathic thrombotic thrombocytopenic purpura (TTP) is an autoimmune disease, in which the underlying ADAMTS13-deficiency is caused by inhibitory autoantibodies against the protease. Human leukocyte antigens (HLA), responsible for antigen presentation, play an important role in the development of antibodies. The loci coding HLA DR and DQ molecules are inherited in linkage as haplotypes. The c.1858C>T polymorphism of the PTPN22 gene, which codes a protein tyrosine phosphatase important in lymphocyte activation, predisposes to a number of autoimmune diseases. We determined the HLA-DRB1-DQB1 haplotypes and the PTPN22 c.1858C>T genotypes in 75 patients with acquired idiopathic TTP and in healthy controls, in order to assess the role of these genetic factors and their interactions in the susceptibility to TTP. We found that the carrier frequencies of the DRB1∗11-DQB1∗03 and DRB1∗15-DQB1∗06 haplotypes were higher, while those of the DRB1∗07-DQB1∗02 and DRB1∗13-DQB1∗06 haplotypes were lower in TTP patients. There was no difference in the overall frequency of the PTPN22 c.1858T allele between TTP patients and controls. In conclusion, we identified four HLA-DRB1-DQB1 haplotypes associated with an increased (DRB1∗11-DQB1∗03 and DRB1∗15-DQB1∗06) or a decreased (DRB1∗07-DQB1∗02 and DRB1∗13-DQB1∗06) susceptibility to acquired idiopathic TTP.
Collapse
Affiliation(s)
- György Sinkovits
- 3rd Dept. of Internal Medicine, Research Laboratory, Semmelweis University, Budapest, Hungary.
| | - Ágnes Szilágyi
- 3rd Dept. of Internal Medicine, Research Laboratory, Semmelweis University, Budapest, Hungary
| | - Péter Farkas
- 3rd Dept. of Internal Medicine, Research Laboratory, Semmelweis University, Budapest, Hungary
| | - Dóra Inotai
- Laboratory of Transplantation Immunogenetics, Hungarian National Blood Transfusion Service, Budapest, Hungary
| | - Anikó Szilvási
- Laboratory of Transplantation Immunogenetics, Hungarian National Blood Transfusion Service, Budapest, Hungary
| | - Attila Tordai
- Dept. of Pathophysiology, Semmelweis University, Budapest, Hungary
| | - Katalin Rázsó
- Dept. of Internal Medicine, University of Debrecen, Debrecen, Hungary
| | - Marienn Réti
- Dept. of Haematology and Stem Cell Transplantation, United St. István and St. László Hospital, Budapest, Hungary
| | - Zoltán Prohászka
- 3rd Dept. of Internal Medicine, Research Laboratory, Semmelweis University, Budapest, Hungary
| |
Collapse
|
26
|
Identification of glycans on plasma-derived ADAMTS13. Blood 2016; 128:e51-e58. [PMID: 27574189 DOI: 10.1182/blood-2016-06-720912] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 08/11/2016] [Indexed: 12/16/2022] Open
Abstract
Patients suffering from acquired thrombotic thrombocytopenic purpura develop autoantibodies directed toward the plasma glycoprotein ADAMTS13. Here, we studied the glycan composition of plasma-derived ADAMTS13. Purified ADAMTS13 was reduced, alkylated, and processed into peptides with either trypsin or chymotrypsin. Glycopeptides were enriched using zwitterionic HILIC zip-tips and analyzed by tandem mass spectrometry employing higher-energy collision dissociation fragmentation. Upon detection of a diagnostic ion of a glycan fragment, electron transfer dissociation fragmentation was performed on the same precursor ion. The majority of N-linked glycans were of the complex type containing terminal sialic acids and fucose residues. A high mannose-containing glycan was attached to Asn614 in the spacer domain. Six O-linked glycans mostly terminating in sialic acid were found dispersed over ADAMTS13. Five O-linked glycans were attached to a Ser and one to Thr. All 6 O-linked glycans contained a terminal sialic acid. O-fucosylation is a common posttranslational modification of thrombospondin type 1 repeats. We identified 7 O-fucosylation sites in the thrombospondin (TSP) type 1 repeats. Unexpectedly, one additional O-fucosylation site was found in the disintegrin domain. This O-fucosylation site did not meet the proposed consensus sequence CSX(S/T)CG. C-mannosylation sites were identified in TSP1, linker TSP4-TSP5, and TSP8. Overall, our findings highlight the complexity of glycan modifications on ADAMTS13, which may have implications for its interaction with immune- or clearance receptors containing carbohydrate recognition domains.
Collapse
|
27
|
Thrombotic Thrombocytopenic Purpura in Black People: Impact of Ethnicity on Survival and Genetic Risk Factors. PLoS One 2016; 11:e0156679. [PMID: 27383202 PMCID: PMC4934773 DOI: 10.1371/journal.pone.0156679] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/18/2016] [Indexed: 02/06/2023] Open
Abstract
Black people are at increased risk of thrombotic thrombocytopenic purpura (TTP). Whether clinical presentation of TTP in Black patients has specific features is unknown. We assessed here differences in TTP presentation and outcome between Black and White patients. Clinical presentation was comparable between both ethnic groups. However, prognosis differed with a lower death rate in Black patients than in White patients (2.7% versus 11.6%, respectively, P = .04). Ethnicity, increasing age and neurologic involvement were retained as risk factors for death in a multivariable model (P < .05 all). Sixty-day overall survival estimated by the Kaplan-Meier curves and compared with the Log-Rank test confirmed that Black patients had a better survival than White patients (P = .03). Salvage therapies were similarly performed between both groups, suggesting that disease severity was comparable. The comparison of HLA-DRB1*11, -DRB1*04 and -DQB1*03 allele frequencies between Black patients and healthy Black individuals revealed no significant difference. However, the protective allele against TTP, HLA-DRB1*04, was dramatically decreased in Black individuals in comparison with White individuals. Black people with TTP may have a better survival than White patients despite a comparable disease severity. A low natural frequency of HLA-DRB1*04 in Black ethnicity may account for the greater risk of TTP in this population.
Collapse
|
28
|
|
29
|
CD4+ T cells from patients with acquired thrombotic thrombocytopenic purpura recognize CUB2 domain-derived peptides. Blood 2016; 127:1606-9. [DOI: 10.1182/blood-2015-10-668053] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/31/2015] [Indexed: 12/19/2022] Open
Abstract
Key Points
CD4+ T-cell responses in 2 patients with acquired TTP. CUB2 domain-derived core peptides are recognized by CD4+ T cells present in 2 patients with acquired TTP.
Collapse
|
30
|
Tersteeg C, Verhenne S, Roose E, Schelpe AS, Deckmyn H, De Meyer SF, Vanhoorelbeke K. ADAMTS13 and anti-ADAMTS13 autoantibodies in thrombotic thrombocytopenic purpura – current perspectives and new treatment strategies. Expert Rev Hematol 2015; 9:209-21. [DOI: 10.1586/17474086.2016.1122515] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
31
|
Sorvillo N, Hartholt RB, Bloem E, Sedek M, ten Brinke A, van der Zwaan C, van Alphen FP, Meijer AB, Voorberg J. von Willebrand factor binds to the surface of dendritic cells and modulates peptide presentation of factor VIII. Haematologica 2015; 101:309-18. [PMID: 26635035 DOI: 10.3324/haematol.2015.137067] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/27/2015] [Indexed: 11/09/2022] Open
Abstract
It has been proposed that von Willebrand factor might affect factor VIII immunogenicity by reducing factor VIII uptake by antigen presenting cells. Here we investigate the interaction of recombinant von Willebrand factor with immature monocyte-derived dendritic cells using flow cytometry and confocal microscopy. Surprisingly, von Willebrand factor was not internalized by immature dendritic cells, but remained bound to the cell surface. As von Willebrand factor reduces the uptake of factor VIII, we investigated the repertoire of factor VIII presented peptides when in complex with von Willebrand factor. Interestingly, factor VIII-derived peptides were still abundantly presented on major histocompatibility complex class II molecules, even though a reduction of factor VIII uptake by immature dendritic cells was observed. Inspection of peptide profiles from 5 different donors showed that different core factor VIII peptide sequences were presented upon incubation with factor VIII/von Willebrand factor complex when compared to factor VIII alone. No von Willebrand factor peptides were detected when immature dendritic cells were pulsed with different concentrations of von Willebrand factor, confirming lack of von Willebrand factor endocytosis. Several von Willebrand factor derived peptides were recovered when cells were pulsed with von Willebrand factor/factor VIII complex, suggesting that factor VIII promotes endocytosis of small amounts of von Willebrand factor by immature dendritic cells. Taken together, our results establish that von Willebrand factor is poorly internalized by immature dendritic cells. We also show that von Willebrand factor modulates the internalization and presentation of factor VIII-derived peptides on major histocompatibility complex class II.
Collapse
Affiliation(s)
- Nicoletta Sorvillo
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands Current address: Harvard Medical School Program in Cellular and Molecular Medicine, Boston Children's Hospital, USA
| | - Robin B Hartholt
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Esther Bloem
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Magdalena Sedek
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Anja ten Brinke
- Department of Immune Pathology, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Carmen van der Zwaan
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Floris P van Alphen
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Alexander B Meijer
- Department of Plasma Proteins, Sanquin Blood Supply Foundation, Amsterdam and the Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, the Netherlands
| | - Jan Voorberg
- Department of Plasma Proteins, Sanquin-AMC Landsteiner Laboratory, Amsterdam, the Netherlands
| |
Collapse
|
32
|
Voorberg J, Verbij FC, Fijnheer R. Disappearing acts of ADAMTS13. EBioMedicine 2015; 2:800-1. [PMID: 26425683 PMCID: PMC4563130 DOI: 10.1016/j.ebiom.2015.07.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 07/08/2015] [Indexed: 12/19/2022] Open
Affiliation(s)
- Jan Voorberg
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Fabian C Verbij
- Department of Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Rob Fijnheer
- Department of Haematology, University Medical Centre Utrecht, Utrecht, The Netherlands
| |
Collapse
|
33
|
[Diagnostic and therapeutic guidelines of thrombotic microangiopathies of the Spanish Apheresis Group]. Med Clin (Barc) 2014; 144:331.e1-331.e13. [PMID: 25433791 DOI: 10.1016/j.medcli.2014.09.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 09/18/2014] [Indexed: 12/18/2022]
Abstract
Thrombotic microangiopathies (TMA) are disorders defined by the presence of a microangiopathic hemolytic anemia (with the characteristic hallmark of schistocytes in the peripheral blood smear), thrombocytopenia and organ malfunction of variable intensity. Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are the most important forms of TMA and, without the adequate treatment, they are associated with high morbimortality. In recent years, significant advances in the knowledge of the pathophysiology of TMA have occurred. Those advances have allowed us to move from a syndromic diagnosis with a similar treatment to all entities to the search of etiologic diagnosis which would lead to a specific treatment, finally leading to a better outcome of the patient. This document pretends to summarize the current status of knowledge of the pathophysiology of TMA and the therapeutic options available, and to offer a diagnostic and therapeutic practical tool to the professionals caring for the patients.
Collapse
|
34
|
Acquired TTP: ADAMTS13 meets the immune system. Blood Rev 2014; 28:227-34. [DOI: 10.1016/j.blre.2014.07.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 07/14/2014] [Indexed: 02/06/2023]
|
35
|
Sorvillo N, Kaijen PH, Matsumoto M, Fujimura Y, van der Zwaan C, Verbij FC, Pos W, Fijnheer R, Voorberg J, Meijer AB. Identification of N-linked glycosylation and putative O-fucosylation, C-mannosylation sites in plasma derived ADAMTS13. J Thromb Haemost 2014; 12:670-9. [PMID: 24977290 DOI: 10.1111/jth.12535] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Acquired deficiency of ADAMTS13 causes a rare and life-threatening disorder called thrombotic thrombocytopenic purpura (TTP). Several studies have shown that aberrant glycosylation can play an important role in the pathogenesis of autoimmune diseases.N-linked glycosylation and putative O-fucosylation sites have been predicted or identified in recombinant ADAMTS13. However, it is not known which of these sites are glycosylated in plasma derived ADAMTS13. OBJECTIVES Here we investigated the presence of putative O-fucosylation, C-mannosylation and N-linked glycosylation sites on plasma derived ADAMTS13. METHODS/RESULTS Sites of N-linked glycosylation were determined by the use of peptide N-glycosidase-F (PNGase F), which removes the entire carbohydrate from the side chain of asparagines. Nine of the 10 predicted N-linked glycosylation sites were identified in or near the metalloproteinase,spacer, thrombospondin type 1 repeat (TSR1) and the CUB domain of plasma ADAMTS13. Moreover, six putative O-fucosylated sites were identified in the TSR domains of plasma ADAMTS13 by performing searches of the tandem mass spectrometry (MS/MS) data for loss of hexose (162 Da), deoxyhexose (146 Da), or hexose deoxyhexose(308 Da). The use of electron transfer dissociation (ETD) allowed for unambiguous identification of the modified sites. In addition to putative O-fucosylation and N-linked glycosylation, two putative C-mannosylation sites were identified within the TSR1 and TSR4 domains of ADAMTS13. CONCLUSIONS Our data identify several glycosylation sites on plasma derived ADAMTS13. We anticipate that our findings may be relevant for the initiation of autoimmune reactivity against ADAMTS13 in patients with acquired TTP.
Collapse
|
36
|
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.
Collapse
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.
| |
Collapse
|