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Kikili Cİ, Kivanç D, Ortaboz D, Şentürk Çiftçi H, Özbalak MM, Yenerel MN, Nalçaci M, Ar MC, Oğuz FS, Beşişik SK. Identification of HLA alleles involved in immune thrombotic thrombocytopenic purpura patients from Turkey. Blood Coagul Fibrinolysis 2024; 35:307-315. [PMID: 39083057 DOI: 10.1097/mbc.0000000000001318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Thrombotic thrombocytopenic purpura (TTP) is one of the rare group disorders classified as thrombotic microangiopathies (TMAs). Approximately 90% of TTP developed immune-mediation by the formation of antibodies against the enzyme ADAMTS-13. The exact cause is unknown. To establish an association between human leukocyte antigen (HLA) and autoimmune basis, as susceptibility or protection against the disease, we contributed a study aiming to evaluate the role of HLA in immune-mediated TTP (iTTP). Considering epidemiological factors such as age, sex, ethnicity, and geographical origins, we contributed the study in our country, Turkey, which consist of a very heterogeneous population. Patients' data collection was retrospectively from electronic database on two University hospitals having big therapeutic apheresis service. Control arm was healthy people registered as stem cell donors matched in terms of age and sex. The frequency of HLA-DRB1 and HLA-DQB1 alleles between acquired TTP and the control group was compared using the chi-square method. Yates correction and logistic regression were performed on these results. A total of 75 iTTP patients and 150 healthy individuals enrolled to the study. HLA-DRB1∗11, HLA-DQB1∗03, HLA-DRB1∗11:01, HLA-DRB1∗14:01, HLA-DRB1∗13:05, HLA-DRB1∗11 + HLA-DQB1∗03 allele pair and HLA-DRB1∗15 + HLA- DQB1∗06 were proved to be susceptibility allele pairs for iTTP. HLA-DRB1∗15, HLA-DRB1∗01:01, HLA-DRB1∗07:01, HLA-DRB1∗13:01, HLA-DRB1∗14:54, HLA-DQB1∗05:01, HLA-DQB1∗02:02 and HLA-DRB1∗07 + HLA-DQB1∗02 allele pair were found to be protective against iTTP. Our findings support an association with iTTP across very heterogenous populations in Turkey.
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Affiliation(s)
| | - Demet Kivanç
- Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University
| | - Damla Ortaboz
- Department of Adult Hematology, Cerrahpaşa Faculty of Medicine, Istanbul University-Cerrahpaşa
| | | | - Mustafa Murat Özbalak
- Department of Adult Hematology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Mustafa Nuri Yenerel
- Department of Adult Hematology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Meliha Nalçaci
- Department of Adult Hematology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Muhlis Cem Ar
- Department of Adult Hematology, Cerrahpaşa Faculty of Medicine, Istanbul University-Cerrahpaşa
| | - Fatma Savran Oğuz
- Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University
| | - Sevgi Kalayoğlu Beşişik
- Department of Adult Hematology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
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Pandey S, Shrivastava A, Harville YI, Cottler-Fox M, Harville TO. HLA-DR-DQ associations, combined with PLASMIC score, are reliable predictors of acquired thrombotic thrombocytopenic purpura (aTTP) and aid in differentiating aTTP from other thrombotic microangiopathies. Hematol Transfus Cell Ther 2024:S2531-1379(24)00012-9. [PMID: 38631980 DOI: 10.1016/j.htct.2023.11.016] [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: 07/26/2023] [Revised: 11/19/2023] [Accepted: 11/29/2023] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND Thrombotic microangiopathies (TMA) are a group of disorders with overlapping clinical features that require urgent intervention. Treatment is based on the recognition of the TMA type, which is often challenging. The aim of this study was to identify specific HLA associations with different TMA types to aid rapid diagnosis and appropriate treatment, since the HLA assay can be completed within five hours. METHODS All 86 consecutive patients who presented to the University of Arkansas for Medical Sciences between May 2013 and January 2021 with a presumptive diagnosis of TMA were included in this study. HLA typing was performed and correlated with other clinical and laboratory studies. RESULTS In comparison with other types of TMA, patients with acquired thrombotic thrombocytopenic purpura (aTTP) showed increased frequencies of HLA-DRB1*11, HLA-DQB1*03:01/19, HLA-DRB1*08 and HLA-DRB3. Combining the presence of these HLA associations with a PLASMIC score of 6 or more achieved a higher positive predictive value (90%) for identifying aTTP than the PLASMIC score alone (69%). In comparison with other TMA types, patients with aTTP showed decreased frequencies of HLA-DRB4, HLA-DRB1*07, HLA-DQB1*02. The HLA-DRB1*07/DQB1*02 was not observed in any aTTP patients (negative predictive value: 100%), and thus the presence of this haplotype essentially rules out aTTP. Further, HLA-DRB1*11/DQB1*03:01/19 was absent in atypical hemolytic uremic syndrome patients. CONCLUSION HLA alleles can be used as an adjunct for the rapid assessment of TMA and can help to differentiate it from other primary and secondary forms of TMA, allowing for earlier definitive therapy.
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Affiliation(s)
- Soumya Pandey
- University of Arkansas for Medical Sciences, Little Rock, AR, USA.
| | | | | | | | - Terry O Harville
- University of Arkansas for Medical Sciences, Little Rock, AR, USA
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3
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Lancellotti S, Sacco M, Tardugno M, Ferretti A, De Cristofaro R. Immune and Hereditary Thrombotic Thrombocytopenic Purpura: Can ADAMTS13 Deficiency Alone Explain the Different Clinical Phenotypes? J Clin Med 2023; 12:3111. [PMID: 37176552 PMCID: PMC10179526 DOI: 10.3390/jcm12093111] [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: 03/13/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy caused by a hereditary or immune-mediated deficiency of the enzyme ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13). TTPs are caused by the following pathophysiological mechanisms: (1) the presence of inhibitory autoantibodies against ADAMTS13; and (2) hereditary mutations of the ADAMTS13 gene, which is present on chromosome 9. In both syndromes, TTP results from a severe deficiency of ADAMTS13, which is responsible for the impaired proteolytic processing of high-molecular-weight von Willebrand factor (HMW-VWF) multimers, which avidly interact with platelets and subendothelial collagen and promote tissue and multiorgan ischemia. Although the acute presentation of the occurring symptoms in acquired and hereditary TTPs is similar (microangiopathic hemolytic anemia, thrombocytopenia, and variable ischemic end-organ injury), their intensity, incidence, and precipitating factors are different, although, in both forms, a severe ADAMTS13 deficiency characterizes their physiopathology. This review is aimed at exploring the possible factors responsible for the different clinical and pathological features occurring in hereditary and immune-mediated TTPs.
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Affiliation(s)
- Stefano Lancellotti
- Servizio Malattie Emorragiche e Trombotiche, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, 00168 Roma, Italy;
| | - Monica Sacco
- Dipartimento di Medicina e Chirurgia Traslazionale, Facoltà di Medicina e Chirurgia “Agostino Gemelli”, Università Cattolica S. Cuore, 00168 Roma, Italy; (M.S.); (M.T.)
| | - Maira Tardugno
- Dipartimento di Medicina e Chirurgia Traslazionale, Facoltà di Medicina e Chirurgia “Agostino Gemelli”, Università Cattolica S. Cuore, 00168 Roma, Italy; (M.S.); (M.T.)
| | - Antonietta Ferretti
- Dipartimento di Medicina e Chirurgia Traslazionale, Facoltà di Medicina e Chirurgia “Agostino Gemelli”, Università Cattolica S. Cuore, 00168 Roma, Italy; (M.S.); (M.T.)
| | - Raimondo De Cristofaro
- Servizio Malattie Emorragiche e Trombotiche, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, 00168 Roma, Italy;
- Dipartimento di Medicina e Chirurgia Traslazionale, Facoltà di Medicina e Chirurgia “Agostino Gemelli”, Università Cattolica S. Cuore, 00168 Roma, Italy; (M.S.); (M.T.)
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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.
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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.
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5
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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.
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ADAMTS13 conformation and immunoprofiles in Japanese patients with immune-mediated thrombotic thrombocytopenic purpura. Blood Adv 2022; 7:131-140. [PMID: 36306339 PMCID: PMC9830168 DOI: 10.1182/bloodadvances.2022008885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/13/2022] [Accepted: 09/30/2022] [Indexed: 01/18/2023] Open
Abstract
Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is an ultrarare thrombotic disease caused by autoantibody-induced ADAMTS13 deficiency. Open ADAMST13 conformation, induced by autoantibodies, was identified as a novel biomarker for iTTP. Determining immunoprofiles in patients with iTTP has been shown to guide the development of novel targeted therapies. However, these studies were done in mainly Caucasian iTTP cohorts. To validate those findings across other ethnic cohorts, we investigated 195 acute TTP plasma samples from the Japanese iTTP registry. Seventy-six of the 195 samples had detectable ADAMTS13 antigen levels, of which 94.7% were shown to have an open ADAMTS13 conformation. A positive correlation was observed between ADAMTS13 inhibitor titers (a diagnostic parameter in Japan) and anti-ADAMTS13 immunoglobulin G autoantibody titers. Studying anti-M, anti-DT, anti-CS, anti-T2-T5, anti-T6-T8, anti-CUB1-2 autoantibodies and the corresponding immunoprofile showed that 73% of the patients had anti-CS autoantibodies and 25.8% had anti-M autoantibodies, with the latter being higher than in Caucasians. Stratifying patients according to their immunoprofiles revealed that the profile with only anti-CS autoantibodies was the most common immunoprofile similar to that in Caucasians (28.9%). Although this profile did not affect the 1-year TTP-related mortality rate, patients with autoantibodies against all 6 ADAMTS13 fragments had a higher risk for TTP-related death than other patients (P = .02). We here validated open ADAMTS13 as a novel biomarker for acute iTTP and determined the dominant immunoprofiling in the Japanese cohort, contributing to setting up the diagnosis and managing guidelines across different ethnic cohorts and developing ADAMTS13 variants that do not bind to the anti-CS autoantibodies.
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Panhuber A, Lamorte G, Bruno V, Cetin H, Bauer W, Höftberger R, Erber AC, Frommlet F, Koneczny I. A systematic review and meta-analysis of HLA class II associations in patients with IgG4 autoimmunity. Sci Rep 2022; 12:9229. [PMID: 35654912 PMCID: PMC9163138 DOI: 10.1038/s41598-022-13042-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 05/13/2022] [Indexed: 11/22/2022] Open
Abstract
Autoimmune diseases caused by pathogenic IgG4 subclass autoantibodies (IgG4-AID) include diseases like MuSK myasthenia gravis, pemphigus vulgaris or thrombotic thrombocytopenic purpura. Their etiology is still unknown. Polymorphisms in the human leukocyte antigen (HLA) gene locus, particularly in HLA-DRB1, are known genetic susceptibility factors for autoimmune diseases. We hypothesized a similar role for HLA polymorphisms in IgG4-AID and conducted a systematic review and meta-analysis with case-control studies on IgG4-AID based on MOOSE/ HuGENet guidelines. Genotype (G) and allele (A) frequencies of HLA-DQB1*05 (G: OR 3.8; 95% CI 2.44-5.9; p < 0.00001; A: OR 2.54; 95% CI 1.82-3.55; p < 0.00001) and HLA-DRB1*14 (G: OR 4.31; 95% CI 2.82-6.59; p < 0.00001; A: OR 4.78; 95% CI 3.52-6.49; p < 0.00001) and the HLA-DRB1*14-DQB1*05 haplotype (OR 6.3; 95% CI 3.28-12.09; p < 0.00001/OR 4.98; 95% CI 3.8-6.53; p < 0.00001) were increased while HLA-DRB1*13 (G: OR 0.48; 95% CI 0.34-0.68; p < 0.0001; A: OR 0.46; 95% CI 0.34-0.62; p < 0.00001) was decreased in IgG4-AID patients. In conclusion, the HLA-DQB1*05, HLA-DRB1*14 alleles and the HLA-DQB1*05-DRB1*14 haplotype could be genetic risk factors that predispose for the production of pathogenic IgG4 autoantibodies and the HLA-DRB1*13 allele may protect from IgG4 autoimmunity.
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Affiliation(s)
- Anja Panhuber
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Giovanni Lamorte
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Veronica Bruno
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Hakan Cetin
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Bauer
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Astrid C Erber
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, Austria
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Florian Frommlet
- Center for Medical Statistics Informatics and Intelligent Systems, Section for Medical Statistics, Medical University of Vienna, Vienna, Austria
| | - Inga Koneczny
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria.
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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.
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Laghmouchi A, Graça NAG, Voorberg J. Emerging Concepts in Immune Thrombotic Thrombocytopenic Purpura. Front Immunol 2021; 12:757192. [PMID: 34858410 PMCID: PMC8631936 DOI: 10.3389/fimmu.2021.757192] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/27/2021] [Indexed: 12/23/2022] Open
Abstract
Immune thrombotic thrombocytopenic purpura (iTTP) is an autoimmune disorder of which the etiology is not fully understood. Autoantibodies targeting ADAMTS13 in iTTP patients have extensively been studied, the immunological mechanisms leading to the breach of tolerance remain to be uncovered. This review addresses the current knowledge on genetic factors associated with the development of iTTP and the interplay between the patient’s immune system and environmental factors in the induction of autoimmunity against ADAMTS13. HLA-DRB1*11 has been identified as a risk factor for iTTP in the Caucasian population. Interestingly, HLA-DRB1*08:03 was recently identified as a risk factor in the Japanese population. Combined in vitro and in silico MHC class II peptide presentation approaches suggest that an ADAMTS13-derived peptide may bind to both HLA-DRB1*11 and HLA-DRB1*08:03 through different anchor-residues. It is apparent that iTTP is associated with the presence of infectious microorganisms, viruses being the most widely associated with development of iTTP. Infections may potentially lead to loss of tolerance resulting in the shift from immune homeostasis to autoimmunity. In the model we propose in this review, infections disrupt the epithelial barriers in the gut or lung, promoting exposure of antigen presenting cells in the mucosa-associated lymphoid tissue to the microorganisms. This may result in breach of tolerance through the presentation of microorganism-derived peptides that are homologous to ADAMTS13 on risk alleles for iTTP.
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Affiliation(s)
- Aicha Laghmouchi
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
| | - Nuno A G Graça
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
| | - Jan Voorberg
- Department of Molecular Hematology, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, Netherlands
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Updates on thrombotic thrombocytopenic purpura: Recent developments in pathogenesis, treatment and survivorship. THROMBOSIS UPDATE 2021. [DOI: 10.1016/j.tru.2021.100062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Transplant-associated thrombotic microangiopathy: theoretical considerations and a practical approach to an unrefined diagnosis. Bone Marrow Transplant 2021; 56:1805-1817. [PMID: 33875812 PMCID: PMC8338557 DOI: 10.1038/s41409-021-01283-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 03/08/2021] [Accepted: 03/24/2021] [Indexed: 02/07/2023]
Abstract
Transplant-associated thrombotic microangiopathy (TA-TMA) is an increasingly recognized complication of hematopoietic stem cell transplant (HSCT) with high morbidity and mortality. The triad of endothelial cell activation, complement dysregulation, and microvascular hemolytic anemia has the potential to cause end organ dysfunction, multiple organ dysfunction syndrome and death, but clinical features mimic other disorders following HSCT, delaying diagnosis. Recent advances have implicated complement as a major contributor and the therapeutic potential of complement inhibition has been explored. Eculizumab has emerged as an effective therapy and narsoplimab (OMS721) has been granted priority review by the FDA. Large studies performed mostly in pediatric patients suggest that earlier recognition and treatment may lead to improved outcomes. Here we present a clinically focused summary of recently published literature and propose a diagnostic and treatment algorithm.
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12
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Bécel G, Faict S, Picod A, Bouzid R, Veyradier A, Coppo P. Thrombotic Thrombocytopenic Purpura: When Basic Science Meets Clinical Research. Hamostaseologie 2021; 41:283-293. [PMID: 33607665 DOI: 10.1055/a-1332-3066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
The therapeutic landscape of thrombotic thrombocytopenic purpura (TTP) is rapidly changing with the recent availability of new targeted therapies. This progressive shift from empiricism to pathophysiology-based treatments reflects an intensive interaction between the continuous findings in the field of basic science and an efficient collaborative clinical research and represents a convincing example of the strength of translational medicine. Despite the rarity of TTP, national and international efforts could circumvent this limitation and shed light on the epidemiology, clinical presentation, prognosis, and long-term outcome of this disease. Importantly, they also provided high-quality results and practice changing studies for the benefit of patients. We report here the most recent therapeutic findings that allowed progressively improving the prognostic of TTP, both at the acute phase and through long-term outcome.
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Affiliation(s)
- Gaëlle Bécel
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France.,Service d'hématologie, Hôpital Saint-Antoine, AP-HP - Sorbonne Université, Paris, France
| | - Sylvia Faict
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France.,Service d'hématologie, Hôpital Saint-Antoine, AP-HP - Sorbonne Université, Paris, France
| | - Adrien Picod
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France.,Service d'hématologie, Hôpital Saint-Antoine, AP-HP - Sorbonne Université, Paris, France
| | - Raïda Bouzid
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France
| | - Agnès Veyradier
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France.,Service d'Hématologie Biologique, Groupe Hospitalier Saint-Louis-Lariboisière, AP-HP, Paris, France.,Université Paris-Diderot, Paris, France
| | - Paul Coppo
- Centre de Référence des MicroAngiopathies Thrombotiques, Paris, France.,Service d'hématologie, Hôpital Saint-Antoine, AP-HP - Sorbonne Université, Paris, France.,Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, USPC, Université Paris Descartes, Paris, France
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13
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Stubbs MJ, Coppo P, Cheshire C, Veyradier A, Dufek S, Levine AP, Thomas M, Patel V, Connolly JO, Hubank M, Benhamou Y, Galicier L, Poullin P, Kleta R, Gale DP, Stanescu H, Scully MA. Identification of a novel genetic locus associated with immune mediated thrombotic thrombocytopenic purpura. Haematologica 2021; 107:574-582. [PMID: 33596643 PMCID: PMC8883548 DOI: 10.3324/haematol.2020.274639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Indexed: 12/05/2022] Open
Abstract
Immune thrombotic thrombocytopenic purpura (iTTP) is an ultra-rare, life-threatening disorder, mediated through severe ADAMTS13 deficiency causing multi-system micro-thrombi formation, and has specific human leukocyte antigen associations. We undertook a large genome-wide association study to investigate additional genetically distinct associations in iTTP. We compared two iTTP patient cohorts with controls, following standardized genome-wide quality control procedures for single-nucleotide polymorphisms and imputed HLA types. Associations were functionally investigated using expression quantitative trait loci (eQTL), and motif binding prediction software. Independent associations consistent with previous findings in iTTP were detected at the HLA locus and in addition a novel association was detected on chromosome 3 (rs9884090, P=5.22x10-10, odds ratio 0.40) in the UK discovery cohort. Meta-analysis, including the French replication cohort, strengthened the associations. The haploblock containing rs9884090 is associated with reduced protein O-glycosyltransferase 1 (POGLUT1) expression (eQTL P<0.05), and functional annotation suggested a potential causative variant (rs71767581). This work implicates POGLUT1 in iTTP pathophysiology and suggests altered post-translational modification of its targets may influence disease susceptibility.
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Affiliation(s)
- Matthew J Stubbs
- Haemostasis Research Unit, UCL (London, UK); Department of Renal Medicine.
| | - Paul Coppo
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine (Paris, France)
| | | | - Agnès Veyradier
- Department d'Hematologie, Centre de Référence des Microangiopathies Thrombotiques, Hôpital Lariboisière (Paris, France)
| | | | | | - Mari Thomas
- Haemostasis Research Unit, UCL (London, UK); National Institute for Health Research Cardiometabolic Programme, UCLH/UCL Cardiovascular BRC (London, UK)
| | | | | | | | - Ygal Benhamou
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine (Paris, France)
| | - Lionel Galicier
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine (Paris, France)
| | - Pascale Poullin
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine (Paris, France)
| | | | | | | | - Marie A Scully
- Haemostasis Research Unit, UCL (London, UK); National Institute for Health Research Cardiometabolic Programme, UCLH/UCL Cardiovascular BRC (London, UK)
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14
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Sukumar S, Lämmle B, Cataland SR. Thrombotic Thrombocytopenic Purpura: Pathophysiology, Diagnosis, and Management. J Clin Med 2021; 10:536. [PMID: 33540569 PMCID: PMC7867179 DOI: 10.3390/jcm10030536] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/24/2021] [Accepted: 01/27/2021] [Indexed: 12/12/2022] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a rare thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, severe thrombocytopenia, and ischemic end organ injury due to microvascular platelet-rich thrombi. TTP results from a severe deficiency of the specific von Willebrand factor (VWF)-cleaving protease, ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13). ADAMTS13 deficiency is most commonly acquired due to anti-ADAMTS13 autoantibodies. It can also be inherited in the congenital form as a result of biallelic mutations in the ADAMTS13 gene. In adults, the condition is most often immune-mediated (iTTP) whereas congenital TTP (cTTP) is often detected in childhood or during pregnancy. iTTP occurs more often in women and is potentially lethal without prompt recognition and treatment. Front-line therapy includes daily plasma exchange with fresh frozen plasma replacement and immunosuppression with corticosteroids. Immunosuppression targeting ADAMTS13 autoantibodies with the humanized anti-CD20 monoclonal antibody rituximab is frequently added to the initial therapy. If available, anti-VWF therapy with caplacizumab is also added to the front-line setting. While it is hypothesized that refractory TTP will be less common in the era of caplacizumab, in relapsed or refractory cases cyclosporine A, N-acetylcysteine, bortezomib, cyclophosphamide, vincristine, or splenectomy can be considered. Novel agents, such as recombinant ADAMTS13, are also currently under investigation and show promise for the treatment of TTP. Long-term follow-up after the acute episode is critical to monitor for relapse and to diagnose and manage chronic sequelae of this disease.
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Affiliation(s)
- Senthil Sukumar
- Division of Hematology, Department of Medicine, The Ohio State University, Columbus, OH 43210, USA;
| | - Bernhard Lämmle
- Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, University of Bern, CH 3010 Bern, Switzerland;
- Center for Thrombosis and Hemostasis, University Medical Center, Johannes Gutenberg University, 55131 Mainz, Germany
- Haemostasis Research Unit, University College London, London WC1E 6BT, UK
| | - Spero R. Cataland
- Division of Hematology, Department of Medicine, The Ohio State University, Columbus, OH 43210, USA;
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15
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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.
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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
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16
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Mancini I, Giacomini E, Pontiggia S, Artoni A, Ferrari B, Pappalardo E, Gualtierotti R, Trisolini SM, Capria S, Facchini L, Codeluppi K, Rinaldi E, Pastore D, Campus S, Caria C, Caddori A, Nicolosi D, Giuffrida G, Agostini V, Roncarati U, Mannarella C, Fragasso A, Podda GM, Birocchi S, Cerbone AM, Tufano A, Menna G, Pizzuti M, Ronchi M, De Fanti A, Amarri S, Defina M, Bocchia M, Cerù S, Gattillo S, Rosendaal FR, Peyvandi F. The HLA Variant rs6903608 Is Associated with Disease Onset and Relapse of Immune-Mediated Thrombotic Thrombocytopenic Purpura in Caucasians. J Clin Med 2020; 9:jcm9103379. [PMID: 33096882 PMCID: PMC7589625 DOI: 10.3390/jcm9103379] [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: 09/07/2020] [Revised: 10/11/2020] [Accepted: 10/15/2020] [Indexed: 12/26/2022] Open
Abstract
Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening thrombotic microangiopathy caused by severe ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motifs 13) deficiency, recurring in 30–50% of patients. The common human leukocyte antigen (HLA) variant rs6903608 was found to be associated with prevalent iTTP, but whether this variant is associated with disease relapse is unknown. To estimate the impact of rs6903608 on iTTP onset and relapse, we performed a case-control and cohort study in 161 Italian patients with a first iTTP episode between 2002 and 2018, and in 456 Italian controls. Variation in rs6903608 was strongly associated with iTTP onset (homozygotes odds ratio (OR) 4.68 (95% confidence interval (CI) 2.67 to 8.23); heterozygotes OR 1.64 (95%CI 0.95 to 2.83)), which occurred over three years earlier for each extra risk allele (β −3.34, 95%CI −6.69 to 0.02). Of 153 survivors (median follow-up 4.9 years (95%CI 3.7 to 6.1)), 44 (29%) relapsed. The risk allele homozygotes had a 46% (95%CI 36 to 57%) absolute risk of relapse by year 6, which was significantly higher than both heterozygotes (22% (95%CI 16 to 29%)) and reference allele homozygotes (30% (95%CI 23 to 39%)). In conclusion, HLA variant rs6903608 is a risk factor for both iTTP onset and relapse. This newly identified biomarker may help with recognizing patients at high risk of relapse, who would benefit from close monitoring or intensified immunosuppressive therapy.
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Affiliation(s)
- Ilaria Mancini
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, 20122 Milan, Italy; (I.M.); (E.G.); (E.P.); (R.G.)
| | - Elisa Giacomini
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, 20122 Milan, Italy; (I.M.); (E.G.); (E.P.); (R.G.)
| | - Silvia Pontiggia
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, 20122 Milan, Italy; (S.P.); (A.A.); (B.F.)
| | - Andrea Artoni
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, 20122 Milan, Italy; (S.P.); (A.A.); (B.F.)
| | - Barbara Ferrari
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, 20122 Milan, Italy; (S.P.); (A.A.); (B.F.)
| | - Emanuela Pappalardo
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, 20122 Milan, Italy; (I.M.); (E.G.); (E.P.); (R.G.)
| | - Roberta Gualtierotti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, 20122 Milan, Italy; (I.M.); (E.G.); (E.P.); (R.G.)
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, 20122 Milan, Italy; (S.P.); (A.A.); (B.F.)
| | - Silvia Maria Trisolini
- Hematology, Department of Translational and Precision Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (S.M.T.); (S.C.)
| | - Saveria Capria
- Hematology, Department of Translational and Precision Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (S.M.T.); (S.C.)
| | - Luca Facchini
- Hematology Unit, Azienda Unità Sanitaria Locale—IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy; (L.F.); (K.C.)
| | - Katia Codeluppi
- Hematology Unit, Azienda Unità Sanitaria Locale—IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy; (L.F.); (K.C.)
| | - Erminia Rinaldi
- Hematology Unit, A. Perrino Hospital, 72100 Brindisi, Italy; (E.R.); (D.P.)
| | - Domenico Pastore
- Hematology Unit, A. Perrino Hospital, 72100 Brindisi, Italy; (E.R.); (D.P.)
| | - Simona Campus
- Pediatric Unit, Ospedale Microcitemico, 09121 Cagliari, Italy;
| | - Cinzia Caria
- Internal Medicine Unit, S.S. Trinità Hospital, 09121 Cagliari, Italy; (C.C.); (A.C.)
| | - Aldo Caddori
- Internal Medicine Unit, S.S. Trinità Hospital, 09121 Cagliari, Italy; (C.C.); (A.C.)
| | - Daniela Nicolosi
- Hematology Division, Department of Clinical and Molecular Biomedicine, University of Catania, 95123 Catania, Italy; (D.N.); (G.G.)
| | - Gaetano Giuffrida
- Hematology Division, Department of Clinical and Molecular Biomedicine, University of Catania, 95123 Catania, Italy; (D.N.); (G.G.)
| | - Vanessa Agostini
- U.O. Medicina Trasfusionale, IRCCS—Ospedale Policlinico San Martino, 16132 Genova, Italy;
| | - Umberto Roncarati
- U.O. Immunoematologia e Medicina Trasfusionale/Officina Trasfusionale, Cesena e Forlì, 47521 Cesena, Italy;
| | - Clara Mannarella
- Hematology Unit, Madonna delle Grazie Hospital, 75100 Matera, Italy; (C.M.); (A.F.)
| | - Alberto Fragasso
- Hematology Unit, Madonna delle Grazie Hospital, 75100 Matera, Italy; (C.M.); (A.F.)
| | - Gian Marco Podda
- U.O. Medicina III, ASST Santi Paolo e Carlo, Dipartimento di Scienze della Salute, Università degli Studi di Milano, 20142 Milan, Italy; (G.M.P.); (S.B.)
| | - Simone Birocchi
- U.O. Medicina III, ASST Santi Paolo e Carlo, Dipartimento di Scienze della Salute, Università degli Studi di Milano, 20142 Milan, Italy; (G.M.P.); (S.B.)
| | - Anna Maria Cerbone
- Department of Clinical Medicine and Surgery, AOU Federico II, 80131 Naples, Italy; (A.M.C.); (A.T.)
| | - Antonella Tufano
- Department of Clinical Medicine and Surgery, AOU Federico II, 80131 Naples, Italy; (A.M.C.); (A.T.)
| | - Giuseppe Menna
- Department of Oncology, AORN Santobono-Pausilipon, 80122 Naples, Italy;
| | | | - Michela Ronchi
- Internal Medicine Unit, Department of Medicine, Lugo Hospital, Lugo, 48022 Ravenna, Italy;
| | - Alessandro De Fanti
- Departmental Simple Unit of Pediatric Rheumatology, AUSL-IRCSS Reggio Emilia, 42123 Reggio Emilia, Italy;
| | - Sergio Amarri
- Paediatrics Unit, AUSL-IRCSS Reggio Emilia, 42123 Reggio Emilia, Italy;
| | - Marzia Defina
- Department of Medical, Surgery and Neuroscience, Hematology Unit, Azienda Ospedaliera Universitaria Senese, Università degli Studi di Siena, 53100 Siena, Italy; (M.D.); (M.B.)
| | - Monica Bocchia
- Department of Medical, Surgery and Neuroscience, Hematology Unit, Azienda Ospedaliera Universitaria Senese, Università degli Studi di Siena, 53100 Siena, Italy; (M.D.); (M.B.)
| | - Silvia Cerù
- Hematology Unit, Santa Chiara Hospital, 38122 Trento, Italy;
| | - Salvatore Gattillo
- Immuno-Hematology and Transfusion Medicine Unit, San Raffaele Hospital, 20132 Milan, Italy;
| | - Frits R. Rosendaal
- Department of Clinical Epidemiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands;
| | - Flora Peyvandi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Fondazione Luigi Villa, 20122 Milan, Italy; (I.M.); (E.G.); (E.P.); (R.G.)
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, 20122 Milan, Italy; (S.P.); (A.A.); (B.F.)
- Correspondence: ; Tel.: +39-02-5503-5414
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17
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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
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18
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Hussein EA. Idiopathic TTP in the Middle East: Epidemiology and clinical outcomes in infection associated episodes. Transfus Apher Sci 2020; 59:102916. [PMID: 32878734 DOI: 10.1016/j.transci.2020.102916] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 07/18/2020] [Accepted: 08/03/2020] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Literature on epidemiology of thrombotic thrombocytopenic purpura (TTP) in the Middle East is scarce. MATERIALS AND METHODS We prospectively examined the association between infection and clinical outcomes in 44 patients with idiopathic TTP, with severely deficient ADAMTS13. We also investigated seasonality of the disease, hoping to better understand the epidemiology of idiopathic TTP. RESULTS Summer demonstrated significantly lower incidence for idiopathic TTP, compared with other seasons P = 0.0003. Fourteen patients had 15 episodes with a suspected concomitant infection. Five initial episodes were triggered by an infection (33.3 %), all presenting in winter, six episodes were associated with an exacerbation (40 %) and infection triggered a relapse in the other four episodes (26.7 %), with 2 episodes presenting in winter. TTP associated infections included: central line infection, urinary tract infection and post-operative infection. One patient had respiratory tract infection, on both his initial and relapsing episodes. Refractoriness to treatment was demonstrated in 4 patients (28.6 %) and it was associated with dental abscess (one patient), septic shock (one patient) and Mycoplasma pneumonia (2 patients). All 4 patients had markedly elevated CRP values with a median of 335 mg/L. CONCLUSION Most of the infection associated episodes developed in winter (77.8 %). In patients with idiopathic TTP refractory to conventional treatment, infection should be seriously considered as an additional contributing factor for their initial and /or recurrent episodes, particularly when CRP is markedly elevated.
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Affiliation(s)
- Eiman A Hussein
- Department of Clinical Pathology, Division of Transfusion Medicine and Blood Banking, Cairo University, Cairo, Egypt.
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19
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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.
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20
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Coppo P. Immune TTP pathogenesis: the rising sun on HLA. Blood 2020; 135:2335-2336. [PMID: 32585027 DOI: 10.1182/blood.2020006078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Paul Coppo
- French Reference Center for Thrombotic Microangiopathies
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21
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Al Haddad C, Finianos P, Zgheib E, Germanos M, Coppo P. Risk factors associated with the human leucocyte antigen system in Lebanese patients with immune-mediated thrombotic thrombocytopenic purpura. Presse Med 2019; 48:1182-1184. [PMID: 31672454 DOI: 10.1016/j.lpm.2019.09.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/20/2019] [Accepted: 09/09/2019] [Indexed: 01/20/2023] Open
Affiliation(s)
- Christian Al Haddad
- Laboratory Department, Notre Dame des Secours University Hospital (CHU-NDS), P.O. Box 3, Jbeil, Lebanon; University of the Holy Spirit Kaslik (USEK), Faculty of Medicine and Medical Sciences, Jounieh, Lebanon; University of the Holy Spirit Kaslik (USEK), Higher Center For Research, Jounieh, Lebanon.
| | - Peter Finianos
- Laboratory Department, Notre Dame des Secours University Hospital (CHU-NDS), P.O. Box 3, Jbeil, Lebanon
| | - Eliane Zgheib
- Laboratory Department, Notre Dame des Secours University Hospital (CHU-NDS), P.O. Box 3, Jbeil, Lebanon; University of the Holy Spirit Kaslik (USEK), Faculty of Medicine and Medical Sciences, Jounieh, Lebanon
| | - Myrna Germanos
- University of the Holy Spirit Kaslik (USEK), Faculty of Medicine and Medical Sciences, Jounieh, Lebanon
| | - Paul Coppo
- Hematology Department, Saint Antoine Hospital AP-HP, Sorbonne University, Paris, France
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Abstract
BACKGROUND Autoimmune thrombocytopenia in immune thrombocytopenic purpura (ITP), thrombotic thrombocytopenic purpura (TTP), and heparin-induced thrombocytopenia (HIT) is associated with immunologic degradation of platelets and reduced platelet counts in patients, leading to bleeding risk in patients. Considering the role of human leukocyte antigens (HLA) in the development of immune response, in this review, we examine the relationship between HLA and pathogenesis of the above-mentioned diseases. METHODS Relevant English-language literature was searched and retrieved from Google Scholar search engine and PubMed database (1979 to 2018). The following keywords were used: "Immune Thrombocytopenic purpura," "Thrombotic Thrombocytopenic Purpura," Human Leukocyte Antigen," and "Heparin-induced thrombocytopenia." RESULTS In autoimmune thrombocytopenia, HLA molecule presents self-antigens or foreign antigens similar to self-antigens, provoking an immune response against platelets that results in the degradation of platelets in peripheral blood and possible bleeding in the patient. For example, HLA-DRB1 *11 presents the self-antigen and induces an immune response against ADAMTS13, which is associated with thrombocytopenia in TTP patients. CONCLUSIONS HLA alleles can be used as prognostic biomarkers for immunologic disorders of platelet such as ITP, TTP, and HIT. Different DRB1 alleles enable the assessment of resistance to common ITP treatments as well as disease prognosis. Due to the genetic association between HLA-DR1 and HLA-DQ1 alleles and the role of HLA-DRB1 *11 in TTP, the HLA-DQB1 *02: 02 allele may also play a role in TTP pathogenesis.
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23
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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.
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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
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24
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Hrdinová J, D'Angelo S, Graça NAG, Ercig B, Vanhoorelbeke K, Veyradier A, Voorberg J, Coppo P. Dissecting the pathophysiology of immune thrombotic thrombocytopenic purpura: interplay between genes and environmental triggers. Haematologica 2018; 103:1099-1109. [PMID: 29674502 PMCID: PMC6029525 DOI: 10.3324/haematol.2016.151407] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 04/13/2018] [Indexed: 01/04/2023] Open
Abstract
Although outstanding progress has been made in understanding the pathophysiology of thrombotic thrombocytopenic purpura (TTP), knowledge of the immunopathogenesis of the disease is only at an early stage. Anti-ADAMTS13 auto-antibodies were shown to block proteolysis of von Willebrand factor and/or induce ADAMTS13 clearance from the circulation. However, it still remains to identify which immune cells are involved in the production of anti-ADAMTS13 autoantibodies, and therefore account for the remarkable efficacy of the B-cell depleting agents in this disease. The mechanisms leading to the loss of tolerance of the immune system towards ADAMTS13 involve the predisposing genetic factors of the human leukocyte antigen class II locus DRB1*11 and DQB1*03 alleles as well as the protective allele DRB1*04, and modifying factors such as ethnicity, sex and obesity. Future studies have to identify why these identified genetic risk factors are also frequently to be found in the healthy population although the incidence of immune-mediated thrombotic thrombocytopenic purpura (iTTP) is extremely low. Moreover, the development of recombinant ADAMTS13 opens a new therapeutic era in the field. Interactions of recombinant ADAMTS13 with the immune system of iTTP patients will require intensive investigation, especially for its potential immunogenicity. Better understanding of iTTP immunopathogenesis should, therefore, provide a basis for the development of novel therapeutic approaches to restore immune tolerance towards ADAMTS13 and thereby better prevent refractoriness and relapses in patients with iTTP. In this review, we address these issues and the related challenges in this field.
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Affiliation(s)
- Johana Hrdinová
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,PharmaTarget B.V., Maastricht, the Netherlands.,Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands
| | - Silvia D'Angelo
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Belgium.,Protobios LLC, Tallinn, Estonia
| | - Nuno A G Graça
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,Icosagen Cell Factory OÜ, Ülenurme Vald, Tartumaa, Estonia
| | - Bogac Ercig
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands.,PharmaTarget B.V., Maastricht, the Netherlands.,Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, IRF Life Sciences, KU Leuven Campus Kulak Kortrijk, Belgium
| | - Agnès Veyradier
- Service d'Hématologie Biologique and EA3518, Groupe Hospitalier Saint Louis-Lariboisière, Assistance Publique - Hôpitaux de Paris, Université Paris Diderot, France.,Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine, AP-HP, Paris, France
| | - Jan Voorberg
- Department of Plasma Proteins, Sanquin-Academic Medical Center Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Paul Coppo
- Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine, AP-HP, Paris, France .,Service d'Hématologie, Assistance Publique - Hôpitaux de Paris, France.,Sorbonne Université, UPMC Univ Paris 06, France
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25
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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.
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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
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26
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Studt JD, Voorberg J, Hovinga JA, Schaller M. Acquired thrombotic thrombocytopenic purpura. Hamostaseologie 2018; 33:121-30. [DOI: 10.5482/hamo-12-12-0023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/17/2013] [Indexed: 01/16/2023] Open
Abstract
SummaryThe von Willebrand factor (VWF)-cleaving metalloprotease, ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motifs-13) is the only known target of the dysregulated immune response in acquired TTP. Autoantibodies to ADAMTS13 either neutralize its activity or accelerate its clearance, thereby causing a severe deficiency of ADAMTS13 in plasma. As a consequence, size regulation of VWF is impaired and the persistence of ultra-large VWF (ULVWF) multimers facilitates micro vascular platelet aggregation causing microangiopathic haemolytic anaemia and ischaemic organ damage. Autoimmune TTP although a rare disease with an annual incidence of 1.72 cases has a mortality rate of 20% even with adequate therapy.We describe the mechanisms involved in ADAMTS13 autoimmunity with a focus on the role of B- and T-cells in the pathogenesis of this disorder. We discuss the potential translation of recent experimental findings into future therapeutic concepts for the treatment of acquired TTP.
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27
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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.
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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
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Abstract
Thrombotic thrombocytopenic purpura (TTP; also known as Moschcowitz disease) is characterized by the concomitant occurrence of often severe thrombocytopenia, microangiopathic haemolytic anaemia and a variable degree of ischaemic organ damage, particularly affecting the brain, heart and kidneys. Acute TTP was almost universally fatal until the introduction of plasma therapy, which improved survival from <10% to 80-90%. However, patients who survive an acute episode are at high risk of relapse and of long-term morbidity. A timely diagnosis is vital but challenging, as TTP shares symptoms and clinical presentation with numerous conditions, including, for example, haemolytic uraemic syndrome and other thrombotic microangiopathies. The underlying pathophysiology is a severe deficiency of the activity of a disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13), the protease that cleaves von Willebrand factor (vWF) multimeric strings. Ultra-large vWF strings remain uncleaved after endothelial cell secretion and anchorage, bind to platelets and form microthrombi, leading to the clinical manifestations of TTP. Congenital TTP (Upshaw-Schulman syndrome) is the result of homozygous or compound heterozygous mutations in ADAMTS13, whereas acquired TTP is an autoimmune disorder caused by circulating anti-ADAMTS13 autoantibodies, which inhibit the enzyme or increase its clearance. Consequently, immunosuppressive drugs, such as corticosteroids and often rituximab, supplement plasma exchange therapy in patients with acquired TTP.
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29
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Hussein E, Teruya J. Evaluating the impact of the ABO blood group on the clinical outcome of thrombotic thrombocytopenic purpura associated with severe ADAMTS13 deficiency. Vox Sang 2017; 112:434-442. [DOI: 10.1111/vox.12511] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 12/03/2016] [Accepted: 02/11/2017] [Indexed: 12/31/2022]
Affiliation(s)
- E. Hussein
- Division of Transfusion Medicine; Department of Clinical Pathology; Cairo University; Cairo Egypt
| | - J. Teruya
- Pathology & Immunology, Pediatrics, and Medicine; Baylor College of Medicine and Texas Children's Hospital; Houston TX USA
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30
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The class I scavenger receptor CD163 promotes internalization of ADAMTS13 by macrophages. Blood Adv 2017; 1:293-305. [PMID: 29296945 DOI: 10.1182/bloodadvances.2016001321] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/19/2016] [Indexed: 01/07/2023] Open
Abstract
Internalization of ADAMTS13 by macrophages may contribute to its clearance from the circulation. Here we investigated endocytic mechanisms that contribute to the uptake of ADAMTS13 by macrophages. Human monocyte-derived macrophages were used to monitor the uptake of fluorescently labeled recombinant ADAMTS13 by flow cytometry. Internalization of ADAMTS13 was blocked upon addition of the cell-permeable dynamin inhibitor dynasore. Partial blocking of ADAMTS13 uptake was observed by using mannan; however, uptake was not affected by an antibody that blocked binding to the macrophage mannose receptor CD206, which suggests that other endocytic receptors contribute to the internalization of ADAMTS13 by macrophages. A pull-down with ADAMTS13 and subsequent mass spectrometric analysis identified the class I scavenger receptor CD163 as a candidate receptor for ADAMTS13. Blocking experiments with monoclonal anti-CD163 antibody EDHu-1 resulted in decreased ADAMTS13 internalization by macrophages. Pronounced inhibition of ADAMTS13 uptake by EDHu-1 was observed in CD163 high-expressing macrophages. In agreement with these findings, CD163-expressing Chinese hamster ovary cells were capable of rapidly internalizing ADAMTS13. Surface plasmon resonance revealed binding of ADAMTS13 to scavenger receptor cysteine-rich domains 1-9 and 1-5 of CD163. Taken together, our data identify CD163 as a major endocytic receptor for ADAMTS13 on macrophages.
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Gödel P, Fischer J, Scheid C, Gathof BS, Wolf J, Rybniker J. Familial acquired thrombotic thrombocytopenic purpura in siblings - no immunogenetic link with associated human leucocyte antigens. Eur J Haematol 2016; 98:311-313. [DOI: 10.1111/ejh.12831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2016] [Indexed: 01/12/2023]
Affiliation(s)
- Philipp Gödel
- 1st Department of Internal Medicine; University of Cologne; Cologne Germany
| | - Julia Fischer
- 1st Department of Internal Medicine; University of Cologne; Cologne Germany
| | - Christoph Scheid
- 1st Department of Internal Medicine; University of Cologne; Cologne Germany
| | | | - Jürgen Wolf
- 1st Department of Internal Medicine; University of Cologne; Cologne Germany
| | - Jan Rybniker
- 1st Department of Internal Medicine; University of Cologne; Cologne Germany
- Center for Molecular Medicine Cologne; University of Cologne; Cologne Germany
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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.
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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
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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.
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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
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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.
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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.
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The potential role of HLA-DRB1*11 in the development and outcome of haematopoietic stem cell transplantation-associated thrombotic microangiopathy. Bone Marrow Transplant 2015; 50:1321-5. [PMID: 26146809 DOI: 10.1038/bmt.2015.161] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 12/11/2022]
Abstract
Transplantation-associated thrombotic microangiopathy (TA-TMA) is a serious complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT) with high mortality rate. We retrospectively studied the frequency, clinical and genetic associations and prognostic effect of TA-TMA, in a total of 425 consecutive adult patients, who underwent allo-HSCT for a malignant haematological condition between 2007 and 2013 at our single centre. TA-TMA developed in 19% of the patients. Unrelated donor type (P<0.001), acute GvHD grades II-IV (P<0.001), myeloablative conditioning regimens (P=0.003), tacrolimus-based GvHD prophylaxis (P=0.003), CMV infection (P=0.003) and carriership for HLA-DRB1*11 (P=0.034) were associated with the development of TA-TMA. Survival was adversely affected by the presence of TA-TMA (P<0.001). Among patients with TA-TMA, the outcome of HLA-DRB1*11 carriers was significantly better compared with non-carriers (P=0.003). As a new finding, our observations suggest that the presence of HLA-DRB1*11 antigen contributes to the development of TA-TMA and affects the outcome.
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Sauvètre G, Grange S, Froissart A, Veyradier A, Coppo P, Benhamou Y. La révolution des anticorps monoclonaux dans la prise en charge des microangiopathies thrombotiques. Rev Med Interne 2015; 36:328-38. [DOI: 10.1016/j.revmed.2014.10.364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 08/22/2014] [Accepted: 10/24/2014] [Indexed: 12/15/2022]
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von Laer Tschudin L, Schwitzgebel VM, von Scheven-Gête A, Blouin JL, Hofer M, Hauschild M, Ansari M, Stoppa-Vaucher S, Phan-Hug F. Diabetes and immune thrombocytopenic purpura: a new association with good response to anti-CD20 therapy. Pediatr Diabetes 2015; 16:138-45. [PMID: 24552605 DOI: 10.1111/pedi.12128] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 12/23/2013] [Accepted: 01/10/2014] [Indexed: 12/19/2022] Open
Abstract
Type 1 diabetes (T1D) is rarely a component of primary immune dysregulation disorders. We report two cases in which T1D was associated with thrombocytopenia. The first patient, a 13-year-old boy, presented with immune thrombocytopenia (ITP), thyroiditis, and, 3 wk later, T1D. Because of severe thrombocytopenia resistant to immunoglobulins, high-dose steroids, and cyclosporine treatment, anti-cluster of differentiation (CD20) therapy was introduced, with consequent normalization of thrombocytes and weaning off of steroids. Three and 5 months after anti-CD20 therapy, levothyroxin and insulin therapy, respectively, were stopped. Ten months after stopping insulin treatment, normal C-peptide and hemoglobin A1c (HbA1c) levels and markedly reduced anti-glutamic acid decarboxylase (GAD) antibodies were measured. A second anti-CD20 trial for relapse of ITP was initiated 2 yr after the first trial. Anti-GAD antibody levels decreased again, but HbA1c stayed elevated and glucose monitoring showed elevated postprandial glycemia, demanding insulin therapy. To our knowledge, this is the first case in which insulin treatment could be interrupted for 28 months after anti-CD20 treatment. In patient two, thrombocytopenia followed a diagnosis of T1D 6 yr previously. Treatment with anti-CD20 led to normalization of thrombocytes, but no effect on T1D was observed. Concerning the origin of the boys' conditions, several primary immune dysregulation disorders were considered. Thrombocytopenia associated with T1D is unusual and could represent a new entity. The diabetes manifestation in patient one was probably triggered by corticosteroid treatment; regardless, anti-CD20 therapy appeared to be efficacious early in the course of T1D, but not long after the initial diagnosis of T1D, as shown for patient two.
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Affiliation(s)
- Letizia von Laer Tschudin
- Division of Endocrinology Diabetology and Obesity, Department of Pediatrics, University Hospital, Lausanne, Switzerland
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Edgar CE, Terrell DR, Vesely SK, Wren JD, Dozmorov IM, Niewold TB, Brown M, Zhou F, Frank MB, Merrill JT, Kremer Hovinga JA, Lämmle B, James JA, George JN, Farris AD. Ribosomal and immune transcripts associate with relapse in acquired ADAMTS13-deficient thrombotic thrombocytopenic purpura. PLoS One 2015; 10:e0117614. [PMID: 25671313 PMCID: PMC4324966 DOI: 10.1371/journal.pone.0117614] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 12/29/2014] [Indexed: 11/18/2022] Open
Abstract
Approximately 40% of patients who survive acute episodes of thrombotic thrombocytopenic purpura (TTP) associated with severe acquired ADAMTS13 deficiency experience one or more relapses. Risk factors for relapse other than severe ADAMTS13 deficiency and ADAMTS13 autoantibodies are unknown. ADAMTS13 autoantibodies, TTP episodes following infection or type I interferon treatment and reported ensuing systemic lupus erythematosus in some patients suggest immune dysregulation. This cross-sectional study asked whether autoantibodies against RNA-binding proteins or peripheral blood gene expression profiles measured during remission are associated with history of prior relapse in acquired ADAMTS13-deficient TTP. Peripheral blood from 38 well-characterized patients with autoimmune ADAMTS13-deficient TTP in remission was examined for autoantibodies and global gene expression. A subset of TTP patients (9 patients, 24%) exhibited a peripheral blood gene signature composed of elevated ribosomal transcripts that associated with prior relapse. A non-overlapping subset of TTP patients (9 patients, 24%) displayed a peripheral blood type I interferon gene signature that associated with autoantibodies to RNA-binding proteins but not with history of relapse. Patients who had relapsed bimodally expressed higher HLA transcript levels independently of ribosomal transcripts. Presence of any one potential risk factor (ribosomal gene signature, elevated HLA-DRB1, elevated HLA-DRB5) associated with relapse (OR = 38.4; p = 0.0002) more closely than any factor alone or all factors together. Levels of immune transcripts typical of natural killer (NK) and T lymphocytes positively correlated with ribosomal gene expression and number of prior episodes but not with time since the most recent episode. Flow cytometry confirmed elevated expression of cell surface markers encoded by these transcripts on T and/or NK cell subsets of patients who had relapsed. These data associate elevated ribosomal and immune transcripts with relapse history in acquired, ADAMTS13-deficient TTP.
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Affiliation(s)
- Contessa E. Edgar
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Deirdra R. Terrell
- Department of Biostatistics & Epidemiology, University of Oklahoma Health Sciences Center (OUHSC), Oklahoma City, Oklahoma, United States of America
| | - Sara K. Vesely
- Department of Biostatistics & Epidemiology, University of Oklahoma Health Sciences Center (OUHSC), Oklahoma City, Oklahoma, United States of America
| | - Jonathan D. Wren
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Igor M. Dozmorov
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Timothy B. Niewold
- Division of Rheumatology and Department of Immunology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael Brown
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Fang Zhou
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Mark Barton Frank
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
| | - Joan T. Merrill
- Clinical Pharmacology Program, OMRF, Oklahoma City, Oklahoma, United States of America
| | - Johanna A. Kremer Hovinga
- Department of Hematology & Central Hematology Laboratory, Inselspital, Bern University Hospital & University of Bern, Bern, Switzerland
| | - Bernhard Lämmle
- Department of Hematology & Central Hematology Laboratory, Inselspital, Bern University Hospital & University of Bern, Bern, Switzerland
| | - Judith A. James
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
- Department of Medicine, OUHSC, Oklahoma City, Oklahoma, United States of America
| | - James N. George
- Department of Biostatistics & Epidemiology, University of Oklahoma Health Sciences Center (OUHSC), Oklahoma City, Oklahoma, United States of America
- Department of Medicine, OUHSC, Oklahoma City, Oklahoma, United States of America
| | - A. Darise Farris
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation (OMRF), Oklahoma City, Oklahoma, United States of America
- * E-mail:
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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]
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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.
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Seasonal distribution of severe ADAMTS13 deficient idiopathic thrombotic thrombocytopenic purpura. J Clin Apher 2013; 29:113-9. [DOI: 10.1002/jca.21300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Accepted: 08/12/2013] [Indexed: 12/29/2022]
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Morgand M, Buffet M, Busson M, Loiseau P, Malot S, Amokrane K, Fortier C, London J, Bonmarchand G, Wynckel A, Provôt F, Poullin P, Vanhille P, Presne C, Bordessoule D, Girault S, Delmas Y, Hamidou M, Mousson C, Vigneau C, Lautrette A, Pourrat J, Galicier L, Azoulay E, Pène F, Mira JP, Rondeau E, Ojeda-Uribe M, Charron D, Maury E, Guidet B, Veyradier A, Tamouza R, Coppo P. High prevalence of infectious events in thrombotic thrombocytopenic purpura and genetic relationship with toll-like receptor 9 polymorphisms: experience of the French Thrombotic Microangiopathies Reference Center. Transfusion 2013; 54:389-97. [PMID: 23711330 DOI: 10.1111/trf.12263] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 04/15/2013] [Accepted: 04/15/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Infectious events have been reported as major environmental triggers of thrombotic thrombocytopenic purpura (TTP). We detail here the potential association between infections and TTP. STUDY DESIGN AND METHODS We recruited randomly and prospectively a cohort of 280 consecutive TTP patients during a 9-year period. Features of infection were systematically recorded. RESULTS Features consistent with an infectious event were observed in 114 patients (41%) at time of TTP diagnosis. Infectious agents were documented in 34 cases and were mainly Gram-negative bacilli. At time of diagnosis infected patients more frequently had fever (p < 0.001). Infections at diagnosis did not impact prognosis and outcome. Thirty-six percent of patients experienced an infectious event during hospitalization, which resulted in more exacerbation of TTP (p = 0.02). Infections were not overrepresented during treatment in patients who received steroids and/or rituximab. Further genetic analysis of toll-like receptor (TLR)-9 functionally relevant polymorphisms revealed that TLR-9 +2848 G and TLR-9 +1174 A genotypes were more frequent in TTP patients than in controls (p = 0.04 and p = 0.026, respectively) and more particularly in patients negative for the Class II human leukocyte antigen system susceptibility allele DRB1*11 (p = 0.001 and p = 0.002, respectively). Haplotypes estimation showed that 1174A-2848G haplotype was significantly more frequent in TTP (p = 0.004), suggesting a primary role for this haplotype variation in conferring a predisposition for acquired TTP. CONCLUSION Infections should be considered as an aggravating factor during the course of TTP. Particular polymorphisms in TLR-9 gene may represent risk factors for TTP.
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Affiliation(s)
- Marjolaine Morgand
- Service d'Hématologie, Centre de Référence des Microangiopathies Thrombotiques, Hôpital Saint-Antoine, Université Pierre et Marie Curie, Paris, France; Service de Réanimation Polyvalente, Hôpitaux Universitaires de l'Est Parisien, AP-HP et UPMC Univ Paris 06, Paris, France; Inserm U1009, Institut Gustave Roussy, Villejuif, France; Laboratoire Jean Dausset d'Immunologie et d'Histocompatibilité & INSERM, AP-HP, UMRS 940, Paris, France; Service d'Immunopathologie, Service de Réanimation, Hôpital Saint-Louis, Université Paris 7 Denis Diderot, Paris, France; Service de Réanimation Médicale, Hôpital Charles Nicolle, Rouen, France; Service de Néphrologie, Hôpital Maison Blanche, Reims, France; Service de Néphrologie, Centre Hospitalier Universitaire, Lille, France; Service d'Hémaphérèse, Service de Médecine Interne, Hôpital de la Conception, Marseille, France; Service de Néphrologie, Centre Hospitalier de Valenciennes, Valenciennes, France; Service de Néphrologie- Médecine Interne, Hôpital Sud, Amiens, France; Service d'Hématologie Clinique et de Thérapie Cellulaire, CHU Dupuytren, Limoges, France; Service de Néphrologie, Hôpital Pellegrin, Bordeaux, France; Service Médecine Interne A, Hôpital Hôtel-Dieu, Nantes, France; Service de Néphrologie, Dijon, France; Service de Néphrologie, Hôpital Pontchaillou, Rennes, France; Service de Réanimation Médicale (7HO), Hôpital Gabriel Montpied, Clermont-Ferrand, France; Service de Néphrologie et Immunologie Clinique, CHU Rangueil, Toulouse, France; Service de Réanimation Polyvalente, AP-HP, Hôpital Cochin, Université Paris 5, Paris, France; Service de Réanimation Néphrologique, Hôpital Tenon, UPMC Université Paris 06, Paris, France; Service d'Hématologie, Hôpital Emile Muller, Mulhouse, France; Service d'Hématologie Biologique, Hôpital Antoine Béclère, AP-HP, Clamart et Université Paris-Sud 11, Le Kremlin-Bicêtre, France
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Preferential HLA-DRB1*11–dependent presentation of CUB2-derived peptides by ADAMTS13-pulsed dendritic cells. Blood 2013; 121:3502-10. [DOI: 10.1182/blood-2012-09-456780] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Key Points
ADAMTS13 derived peptides presented on HLA-DR; implications for acquired TTP. CUB2 domain peptide binds to risk-allele HLA-DRB1*11.
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Abstract
Abstract
The regulation of VWF multimer size is essential in preventing spontaneous microvascular platelet clumping, a central pathophysiologic finding in thrombotic thrombocytopenic purpura (TTP). In the majority of TTP patients, ADAMTS13, the principal regulator of VWF size, is severely deficient. Today, 2 forms of severe ADAMTS13 deficiency are recognized. The acquired form is caused by circulating autoantibodies inhibiting ADAMTS13 activity or increasing ADAMTS13 clearance. Pathogenic anti-ADAMTS13 Abs are mainly of the IgG class, predominantly of subclass IgG4, and inhibitory Abs recognize a defined epitope in the ADAMTS13 spacer domain. The reasons underlying the failure to maintain immunologic tolerance to ADAMTS13, however, are still poorly understood. Constitutional ADAMTS13 deficiency leading to hereditary TTP, also known as Upshaw-Schulman syndrome, is the result of homozygous or compound heterozygous ADAMTS13 gene mutations.
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