1
|
Raina R, Mangat G, Hong G, Shah R, Nair N, Abboud B, Bagga S, Sethi SK. Anti-factor H antibody and its role in atypical hemolytic uremic syndrome. Front Immunol 2022; 13:931210. [PMID: 36091034 PMCID: PMC9448717 DOI: 10.3389/fimmu.2022.931210] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 08/08/2022] [Indexed: 11/19/2022] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) an important form of a thrombotic microangiopathy (TMA) that can frequently lead to acute kidney injury (AKI). An important subset of aHUS is the anti-factor H associated aHUS. This variant of aHUS can occur due to deletion of the complement factor H genes, CFHR1 and CFHR3, along with the presence of anti-factor H antibodies. However, it is a point of interest to note that not all patients with anti-factor H associated aHUS have a CFHR1/R3 deletion. Factor-H has a vital role in the regulation of the complement system, specifically the alternate pathway. Therefore, dysregulation of the complement system can lead to inflammatory or autoimmune diseases. Patients with this disease respond well to treatment with plasma exchange therapy along with Eculizumab and immunosuppressant therapy. Anti-factor H antibody associated aHUS has a certain genetic predilection therefore there is focus on further advancements in the diagnosis and management of this disease. In this article we discuss the baseline characteristics of patients with anti-factor H associated aHUS, their triggers, various treatment modalities and future perspectives.
Collapse
Affiliation(s)
- Rupesh Raina
- Department of Nephrology, Akron Children’s Hospital, Akron, OH, United States
- Department of Nephrology, Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH, United States
- *Correspondence: Rupesh Raina, ;
| | - Guneive Mangat
- Department of Nephrology, Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH, United States
| | - Gordon Hong
- Department of Medicine, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Raghav Shah
- Department of Medicine, Ohio States University, Columbus, OH, United States
| | - Nikhil Nair
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Brian Abboud
- Department of Medicine, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Sumedha Bagga
- Questrom School of Business, Boston University, Boston, MA, United States
| | - Sidharth Kumar Sethi
- Paediatric Nephrology & Paediatric Kidney Transplantation, Kidney and Urology Institute, Medanta, The Medicity Hospital, Gurgaon, India
| |
Collapse
|
2
|
Raina R, Vijayvargiya N, Khooblall A, Melachuri M, Deshpande S, Sharma D, Mathur K, Arora M, Sethi SK, Sandhu S. Pediatric Atypical Hemolytic Uremic Syndrome Advances. Cells 2021; 10:3580. [PMID: 34944087 PMCID: PMC8700093 DOI: 10.3390/cells10123580] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/30/2022] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare disorder characterized by dysregulation of the alternate pathway. The diagnosis of aHUS is one of exclusion, which complicates its early detection and corresponding intervention to mitigate its high rate of mortality and associated morbidity. Heterozygous mutations in complement regulatory proteins linked to aHUS are not always phenotypically active, and may require a particular trigger for the disease to manifest. This list of triggers continues to expand as more data is aggregated, particularly centered around COVID-19 and pediatric vaccinations. Novel genetic mutations continue to be identified though advancements in technology as well as greater access to cohorts of interest, as in diacylglycerol kinase epsilon (DGKE). DGKE mutations associated with aHUS are the first non-complement regulatory proteins associated with the disease, drastically changing the established framework. Additional markers that are less understood, but continue to be acknowledged, include the unique autoantibodies to complement factor H and complement factor I which are pathogenic drivers in aHUS. Interventional therapeutics have undergone the most advancements, as pharmacokinetic and pharmacodynamic properties are modified as needed in addition to their as biosimilar counterparts. As data continues to be gathered in this field, future advancements will optimally decrease the mortality and morbidity of this disease in children.
Collapse
Affiliation(s)
- Rupesh Raina
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
- Department of Nephrology, Akron Children’s Hospital, Akron, OH 44308, USA
| | - Nina Vijayvargiya
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
| | - Amrit Khooblall
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
| | - Manasa Melachuri
- Department of Medicine, Northeast Ohio Medical University, Rootstown, OH 44272, USA; (M.M.); (D.S.)
| | - Shweta Deshpande
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
| | - Divya Sharma
- Department of Medicine, Northeast Ohio Medical University, Rootstown, OH 44272, USA; (M.M.); (D.S.)
| | - Kashin Mathur
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
| | - Manav Arora
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA; (N.V.); (A.K.); (S.D.); (K.M.); (M.A.)
| | - Sidharth Kumar Sethi
- Pediatric Nephrology & Pediatric Kidney Transplantation, Kidney and Urology Institute, Medanta, The Medicity Hospital, Gurgaon 122007, India;
| | - Sonia Sandhu
- Hematology and Oncology, Cleveland Clinic Akron General Medical Center, Akron, OH 44307, USA;
| |
Collapse
|
3
|
Zarantonello A, Pedersen H, Laursen NS, Andersen GR. Nanobodies Provide Insight into the Molecular Mechanisms of the Complement Cascade and Offer New Therapeutic Strategies. Biomolecules 2021; 11:biom11020298. [PMID: 33671302 PMCID: PMC7922070 DOI: 10.3390/biom11020298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 01/22/2023] Open
Abstract
The complement system is part of the innate immune response, where it provides immediate protection from infectious agents and plays a fundamental role in homeostasis. Complement dysregulation occurs in several diseases, where the tightly regulated proteolytic cascade turns offensive. Prominent examples are atypical hemolytic uremic syndrome, paroxysmal nocturnal hemoglobinuria and Alzheimer’s disease. Therapeutic intervention targeting complement activation may allow treatment of such debilitating diseases. In this review, we describe a panel of complement targeting nanobodies that allow modulation at different steps of the proteolytic cascade, from the activation of the C1 complex in the classical pathway to formation of the C5 convertase in the terminal pathway. Thorough structural and functional characterization has provided a deep mechanistic understanding of the mode of inhibition for each of the nanobodies. These complement specific nanobodies are novel powerful probes for basic research and offer new opportunities for in vivo complement modulation.
Collapse
Affiliation(s)
- Alessandra Zarantonello
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (A.Z.); (H.P.)
| | - Henrik Pedersen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (A.Z.); (H.P.)
| | - Nick S. Laursen
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark;
| | - Gregers R. Andersen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (A.Z.); (H.P.)
- Correspondence: ; Tel.: +45-30256646
| |
Collapse
|
4
|
Boudhabhay I, Grunenwald A, Roumenina LT. Complement C3 Deposition on Endothelial Cells Revealed by Flow Cytometry. Methods Mol Biol 2021; 2227:97-105. [PMID: 33847934 DOI: 10.1007/978-1-0716-1016-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The three pathways of the complement system converge toward the cleavage of the central complement component C3 into its activated fragments, with C3b being able to bind covalently to the activating surface. The endothelial cells are among the major targets for complement attack in pathological conditions, as the atypical hemolytic uremic syndrome. Therefore, study of complement C3 deposition on endothelial cells by flow cytometry is a sensitive test to measure complement activation. This test can be used as a research or clinical tool to test complement activation induced by patients' sera or to test the functional consequences of newly discovered complement mutations as well as different triggers of endothelial cells injury.
Collapse
Affiliation(s)
- Idris Boudhabhay
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, USPC, Université Paris Descartes, Université Paris Diderot, Paris, France
| | - Anne Grunenwald
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, USPC, Université Paris Descartes, Université Paris Diderot, Paris, France
| | - Lubka T Roumenina
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, USPC, Université Paris Descartes, Université Paris Diderot, Paris, France.
| |
Collapse
|
5
|
Chabannes M, Togarsimalemath SK, Dragon-Durey MA. Hemolytic Tests Exploring Factor H Functional Activities. Methods Mol Biol 2021; 2227:69-81. [PMID: 33847932 DOI: 10.1007/978-1-0716-1016-9_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Impairment of the complement regulatory protein Factor H (FH) is implicated in the physiopathological mechanisms of different diseases like atypical hemolytic and uremic syndrome and C3 glomerulopathies. It may be due to genetic abnormalities or acquired with the development of autoantibodies. FH has several ligands; therefore, the exploration of its functions requires to perform different tests. Among them, two hemolytic tests are very useful because they give specific and complementary information about FH functions. The first one is dedicated to explore the FH capacity to dissociate the alternative pathway C3 convertase, whereas the second one is designed to explore the capacity of FH to bind cell surfaces and to protect them from complement attack. This chapter describes the procedures to perform these two hemolytic tests, exploring in a complementary way the FH functionality.
Collapse
Affiliation(s)
- Melchior Chabannes
- INSERM, UMRS 1138, "Inflammation, Complement and Cancer" Team, Centre de Recherche des Cordeliers, Sorbonne Université, Université de Paris, Paris, France
| | - Shambhuprasad K Togarsimalemath
- INSERM, UMRS 1138, "Inflammation, Complement and Cancer" Team, Centre de Recherche des Cordeliers, Sorbonne Université, Université de Paris, Paris, France
| | - Marie-Agnès Dragon-Durey
- INSERM, UMRS 1138, "Inflammation, Complement and Cancer" Team, Centre de Recherche des Cordeliers, Sorbonne Université, Université de Paris, Paris, France.
- Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Assistance Publique-Hôpitaux de Paris, Paris, France.
| |
Collapse
|
6
|
Abstract
The complement system is a key part of innate immunity. However, if the system becomes dysregulated, damage to healthy host cells can occur, especially to the glomerular cells of the kidney. The convertases of the alternative pathway of the complement system play a crucial role in complement activation. In healthy conditions, their activity is strictly regulated. In patients with diseases caused by complement alternative pathway dysregulation, such as C3 glomerulopathy and atypical hemolytic uremic syndrome, factors can be present in the blood that disturb this delicate balance, leading to convertase overactivity. Such factors include C3 nephritic factors, which are autoantibodies against the C3 convertase that prolong its activity, or genetic variants resulting in a stabilized convertase complex. This chapter describes a method in which the activity and stability of the alternative pathway convertases can be measured to detect aberrant serum factors causing convertase overactivity.
Collapse
Affiliation(s)
- Marloes A H M Michels
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Nicole C A J van de Kar
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Elena B Volokhina
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Bert L P W J van den Heuvel
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
- Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
- Department of Pediatrics/Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium.
- Department of Development and Regeneration, University Hospitals Leuven, Leuven, Belgium.
| |
Collapse
|
7
|
Ville S, Le Bot S, Chapelet-Debout A, Blancho G, Fremeaux-Bacchi V, Deltombe C, Fakhouri F. Atypical HUS relapse triggered by COVID-19. Kidney Int 2020; 99:267-268. [PMID: 33188793 PMCID: PMC7657017 DOI: 10.1016/j.kint.2020.10.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 10/25/2020] [Accepted: 10/27/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Simon Ville
- Institut de Transplantation Urologie Néphrologie, Centre Hospitalier Universitaire de Nantes, Nantes, France; Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, Nantes, France.
| | - Sabine Le Bot
- Institut de Transplantation Urologie Néphrologie, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Agnès Chapelet-Debout
- Institut de Transplantation Urologie Néphrologie, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Gilles Blancho
- Institut de Transplantation Urologie Néphrologie, Centre Hospitalier Universitaire de Nantes, Nantes, France; Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, Nantes, France
| | - Véronique Fremeaux-Bacchi
- Assistance Publique-Hôpitaux de Paris, Laboratory of Immunology, Hôpital Européen Georges Pompidou, Paris, France
| | - Clément Deltombe
- Institut de Transplantation Urologie Néphrologie, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Fadi Fakhouri
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
8
|
Chauhan AJ, Wiffen LJ, Brown TP. COVID-19: A collision of complement, coagulation and inflammatory pathways. J Thromb Haemost 2020; 18:2110-2117. [PMID: 32608159 PMCID: PMC7361520 DOI: 10.1111/jth.14981] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 12/13/2022]
Abstract
COVID-19 is frequently accompanied by a hypercoagulable inflammatory state with microangiopathic pulmonary changes that can precede the diffuse alveolar damage characteristic of typical acute respiratory distress syndrome (ARDS) seen in other severe pathogenic infections. Parallels with systemic inflammatory disorders such as atypical hemolytic uremic syndrome (aHUS) have implicated the complement pathway in the pathogenesis of COVID-19, and particularly the anaphylatoxins C3a and C5a released from cleavage of C3 and C5, respectively. C5a is a potent cell signalling protein that activates a cytokine storm-a hyper-inflammatory phenomenon-within hours of infection and the innate immune response. However, excess C5a can result in a pro-inflammatory environment orchestrated through a plethora of mechanisms that propagate lung injury, lymphocyte exhaustion, and an immune paresis. Furthermore, disruption of the homeostatic interactions between complement and extrinsic and intrinsic coagulation pathways contributes to a net pro-coagulant state in the microvasculature of critical organs. Fatal COVID-19 has been associated with a systemic inflammatory response accompanied by a pro-coagulant state and organ damage, particularly microvascular thrombi in the lungs and kidneys. Pathologic studies report strong evidence of complement activation. C5 blockade reduces inflammatory cytokines and their manifestations in animal studies, and has shown benefits in patients with aHUS, prompting investigation of this approach in the treatment of COVID-19. This review describes the role of the complement pathway and particularly C5a and its aberrations in highly pathogenic virus infections, and therefore its potential as a therapeutic target in COVID-19.
Collapse
Affiliation(s)
- Anoop J Chauhan
- Research and Innovation, Queen Alexandra Hospital, Portsmouth, UK
- Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
- Respiratory Medicine, Queen Alexandra Hospital, Portsmouth, UK
| | - Laura J Wiffen
- Research and Innovation, Queen Alexandra Hospital, Portsmouth, UK
- Respiratory Medicine, Queen Alexandra Hospital, Portsmouth, UK
| | - Thomas P Brown
- Research and Innovation, Queen Alexandra Hospital, Portsmouth, UK
- Respiratory Medicine, Queen Alexandra Hospital, Portsmouth, UK
| |
Collapse
|
9
|
Amann K, Daniel C, Büttner-Herold M. [The complement system-a "hot topic" not only for kidney diseases]. Pathologe 2020; 41:238-247. [PMID: 32240352 DOI: 10.1007/s00292-020-00773-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Increasing interest in the role of the complement system in systemic and renal disease is based on new pathophysiological and therapeutic insights of the recent past and particularly in genetic analyses in children with atypical hemolytic uremic syndrome (aHUS). aHUS is the prototypical systemic disease associated with excessive activation of the alternative complement pathway and manifests in the kidney, but also in other organs as thrombotic microangiopathy (TMA). Pathomechanisms discovered to induce the overactivation of the alternative complement pathway in aHUS led to the first successful therapeutic application of a C5b9 inhibitor. This suppression of the terminal complement cascade succeeded in inhibiting local tissue damage. Thereafter, thanks to advanced modern technologies, further systemic and renal diseases associated with mutations or auto-antibodies targeting the complement pathway were identified. Hereby, disease onset is frequently associated with an additional trigger, e.g. infection or hormonal alterations/imbalances, against the background of a pre-existing predisposition of the patient.Due to the growing understanding of the regulation, and thus the possibility of therapeutic modulation of the different complement pathways, and due to the increasing availability of a variety of drugs inhibiting the complement system, interest in complement-mediated systemic and renal disease has been steadily increasing, making it a "hot-topic" in medicine in recent years.
Collapse
Affiliation(s)
- Kerstin Amann
- Abt. Nephropathologie, Pathologisches Institut, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Krankenhausstr. 8-10, 91054, Erlangen, Deutschland.
| | - Christoph Daniel
- Abt. Nephropathologie, Pathologisches Institut, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Krankenhausstr. 8-10, 91054, Erlangen, Deutschland
| | - Maike Büttner-Herold
- Abt. Nephropathologie, Pathologisches Institut, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Krankenhausstr. 8-10, 91054, Erlangen, Deutschland
| |
Collapse
|
10
|
Frémeaux-Bacchi V, Sellier-Leclerc AL, Vieira-Martins P, Limou S, Kwon T, Lahoche A, Novo R, Llanas B, Nobili F, Roussey G, Cailliez M, Ulinski T, Deschênes G, Alberti C, Weill FX, Mariani P, Loirat C. Complement Gene Variants and Shiga Toxin-Producing Escherichia coli-Associated Hemolytic Uremic Syndrome: Retrospective Genetic and Clinical Study. Clin J Am Soc Nephrol 2019; 14:364-377. [PMID: 30674459 PMCID: PMC6419292 DOI: 10.2215/cjn.05830518] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 12/04/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVES Inherited complement hyperactivation is critical for the pathogenesis of atypical hemolytic uremic syndrome (HUS) but undetermined in postdiarrheal HUS. Our aim was to investigate complement activation and variants of complement genes, and their association with disease severity in children with Shiga toxin-associated HUS. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Determination of complement biomarkers levels and next-generation sequencing for the six susceptibility genes for atypical HUS were performed in 108 children with a clinical diagnosis of post-diarrheal HUS (75 Shiga toxin-positive, and 33 Shiga toxin-negative) and 80 French controls. As an independent control cohort, we analyzed the genotypes in 503 European individuals from the 1000 Genomes Project. RESULTS During the acute phase of HUS, plasma levels of C3 and sC5b-9 were increased, and half of patients had decreased membrane cofactor protein expression, which normalized after 2 weeks. Variants with minor allele frequency <1% were identified in 12 Shiga toxin-positive patients with HUS (12 out of 75, 16%), including pathogenic variants in four (four out of 75, 5%), with no significant differences compared with Shiga toxin-negative patients with HUS and controls. Pathogenic variants with minor allele frequency <0.1% were found in three Shiga toxin-positive patients with HUS (three out of 75, 4%) versus only four European controls (four out of 503, 0.8%) (odds ratio, 5.2; 95% confidence interval, 1.1 to 24; P=0.03). The genetic background did not significantly affect dialysis requirement, neurologic manifestations, and sC5b-9 level during the acute phase, and incident CKD during follow-up. However, the only patient who progressed to ESKD within 3 years carried a factor H pathogenic variant. CONCLUSIONS Rare variants and complement activation biomarkers were not associated with severity of Shiga toxin-associated HUS. Only pathogenic variants with minor allele frequency <0.1% are more frequent in Shiga toxin-positive patients with HUS than in controls.
Collapse
Affiliation(s)
- Véronique Frémeaux-Bacchi
- Service d’Immunologie, Hôpital Européen Georges Pompidou, Assistance Publique-Hôpitaux de Paris, Paris, France
- Team “Complement and Disease,” Centre de recherche des Cordeliers, Sorbonne Université, INSERM, Paris, France
| | | | - Paula Vieira-Martins
- Service d’Immunologie, Hôpital Européen Georges Pompidou, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Sophie Limou
- Institute for Transplantation in Urology and Nephrology, Centre Hospitalo-Universitaire de Nantes, Centre de Recherche en Transplantation et Immunologie, Institut National de la Santé et de la Recherche Médicale U1064, Université de Nantes, Ecole Centrale de Nantes, Nantes, France
| | | | - Annie Lahoche
- Pediatric Nephrology Department, Hôpital Jeanne de Flandre, Centre Hospitalo-Universitaire de Lille, Lille, France
| | - Robert Novo
- Pediatric Nephrology Department, Hôpital Jeanne de Flandre, Centre Hospitalo-Universitaire de Lille, Lille, France
| | - Brigitte Llanas
- Pediatric Nephrology Department, Centre Hospitalo-Universitaire de Bordeaux, Bordeaux, France
| | - François Nobili
- Pediatric Nephrology Department, Centre Hospitalo-Universitaire de Besançon, Besançon, France
| | - Gwenaëlle Roussey
- Pediatric Nephrology Department, Centre Hospitalo-Universitaire de Nantes, Nantes, France
| | - Mathilde Cailliez
- Pediatric Nephrology Department, Centre Hospitalo-Universitaire de Marseille, Marseille, France
| | - Tim Ulinski
- Pediatric Nephrology Department, Hôpital Trousseau, University Pierre and Marie Curie, Assistance Publique-Hôpitaux de Paris, Paris, France; and
| | | | - Corinne Alberti
- Unit of Clinical Epidemiology, Institut National de la Santé et de la Recherche Médicale U1123 and Centre d'Investigation Clinique-Epidémiologie Clinique 1426, and
| | - François-Xavier Weill
- Institut Pasteur, Unité des Bactéries Pathogènes Entériques, Centre National de Référence des Escherichia coli, Shigella et Salmonella, Paris, France
| | - Patricia Mariani
- Laboratory of Microbiology, Escherichia coli Associated National Reference Center, Hôpital Robert Debré, University Paris Diderot, Assistance Publique-Hôpitaux de Paris, Paris, France
| | | |
Collapse
|
11
|
Sridharan M, Go RS, Abraham RS, Fervenza FC, Sethi S, Bryant SC, Spears GM, Murray DL, Willrich MAV. Diagnostic Utility of Complement Serology for Atypical Hemolytic Uremic Syndrome. Mayo Clin Proc 2018; 93:1351-1362. [PMID: 30286829 DOI: 10.1016/j.mayocp.2018.07.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 06/24/2018] [Accepted: 07/17/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To investigate the clinical utility of a 9-analyte complement serology panel (COMS) covering complement function (CH50 and AH50), components (C3, C4), factor B (CFB), factor H, and activation markers (C4d, Bb, and soluble membrane attack complex) for the diagnosis of atypical hemolytic uremic syndrome (aHUS). METHODS Physician orders for COMS from January 19, 2015, through November 4, 2016, were reviewed. Demographic characteristics, patient diagnosis, and laboratory parameters were recorded. RESULTS There were 177 COMS orders for 147 patients. The median patient age was 44.9 years (range, 0.9-88.0 years). Common reasons for ordering COMS included monitoring and diagnosis of C3 glomerulopathy and renal dysfunction and differentiation of aHUS from other thrombotic microangiopathies (TMAs). Forty-four patients had COMS ordered for TMAs: 8 had aHUS and all had 1 or more abnormalities within the alternative pathway of complement. Although the sensitivity of this finding for the diagnosis of aHUS is 100%, the specificity is only 28%, with a positive likelihood ratio of 1.39. Patients with aHUS had lower CH50, C3, and CFB than did those with secondary non-aHUS TMA (all P<.01). A combined CFB of 20.9 mg/dL or less and CH50 of 56% or less led to sensitivity of 75% with increased specificity of 88.9% and a diagnostic odds ratio of 24. CONCLUSION A COMS abnormality should not be interpreted in isolation. In conjunction with clinical presentation, a decrease in both CFB and CH50 may be an important clue to support the diagnosis of aHUS.
Collapse
Affiliation(s)
| | - Ronald S Go
- Division of Hematology, Mayo Clinic, Rochester, MN
| | - Roshini S Abraham
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | | | - Sanjeev Sethi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Sandra C Bryant
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - Grant M Spears
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - David L Murray
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Maria A V Willrich
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN.
| |
Collapse
|
12
|
Zewde N, Morikis D. A computational model for the evaluation of complement system regulation under homeostasis, disease, and drug intervention. PLoS One 2018; 13:e0198644. [PMID: 29874282 PMCID: PMC5991421 DOI: 10.1371/journal.pone.0198644] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/22/2018] [Indexed: 12/21/2022] Open
Abstract
The complement system is an intricate defense network that rapidly removes invading pathogens. Although many complement regulators are present to protect host cells under homeostasis, the impairment of Factor H (FH) regulatory mechanism has been associated with several autoimmune and inflammatory diseases. To understand the dynamics involved in the pivotal balance between activation and regulation, we have developed a comprehensive computational model of the alternative and classical pathways of the complement system. The model is composed of 290 ordinary differential equations with 142 kinetic parameters that describe the state of complement system under homeostasis and disorder through FH impairment. We have evaluated the state of the system by generating concentration-time profiles for the biomarkers C3, C3a-desArg, C5, C5a-desArg, Factor B (FB), Ba, Bb, and fC5b-9 that are influenced by complement dysregulation. We show that FH-mediated disorder induces substantial levels of complement activation compared to homeostasis, by generating reduced levels of C3 and FB, and to a lesser extent C5, and elevated levels of C3a-desArg, Ba, Bb, C5a-desArg, and fC5b-9. These trends are consistent with clinically observed biomarkers associated with complement-mediated diseases. Furthermore, we introduced therapy states by modeling known inhibitors of the complement system, a compstatin variant (C3 inhibitor) and eculizumab (C5 inhibitor). Compstatin demonstrates strong restorative effects for early-stage biomarkers, such as C3a-desArg, FB, Ba, and Bb, and milder restorative effects for late-stage biomarkers, such as C5a-desArg and fC5b-9, whereas eculizumab has strong restorative effects on late-stage biomarkers, and negligible effects on early-stage biomarkers. These results highlight the need for patient-tailored therapies that target early complement activation at the C3 level, or late-stage propagation of the terminal cascade at the C5 level, depending on the specific FH-mediated disease and the manifestations of a patient's genetic profile in complement regulatory function.
Collapse
Affiliation(s)
- Nehemiah Zewde
- Department of Bioengineering, University of California, Riverside, California, United States of America
| | - Dimitrios Morikis
- Department of Bioengineering, University of California, Riverside, California, United States of America
| |
Collapse
|
13
|
Nieto-Ríos JF, Zuluaga-Quintero M, Bello-Márquez DC, Aristizabal-Alzate A, Ocampo-Kohn C, Serna-Higuita LM, Arias L, Zuluaga-Valencia G. Successful kidney transplant with eculizumab, thymoglobulin and belatacept therapy in a highly-sensitised patient with atypical haemolytic uraemic syndrome due to factor H mutation. Nefrologia 2018; 38:433-437. [PMID: 29778558 DOI: 10.1016/j.nefro.2017.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 06/04/2017] [Accepted: 09/17/2017] [Indexed: 11/19/2022] Open
Abstract
Atypical haemolytic uremic syndrome is a disease caused by complement regulation abnormalities that generally progresses to chronic end-stage renal disease with a high rate of recurrence in kidney transplantation and a high risk of graft loss. Anti-complement therapy has improved the prognosis of these patients, achieving disease remission in most cases, increasing the likelihood of a successful kidney transplant and increasing patient and graft survival. Drugs with low risk of induction of thrombotic microangiopathies such as belatacept and mycophenolate have also been used with satisfactory results. We present the case of a young patient at high immunological risk, with atypical haemolytic uraemic syndrome due to factor H mutation, who underwent a successful kidney transplantation with eculizumab, thymoglobulin, belatacept, mycophenolate and steroids, to date preserving excellent graft function without disease recurrence.
Collapse
Affiliation(s)
- John Fredy Nieto-Ríos
- Departamento de Nefrología y Trasplante Renal,Hospital Pablo Tobón Uribe, Medellín, Colombia; Departamento de Medicina Interna y Nefrología, Universidad de Antioquia, Medellín, Colombia.
| | | | | | | | - Catalina Ocampo-Kohn
- Departamento de Nefrología y Trasplante Renal,Hospital Pablo Tobón Uribe, Medellín, Colombia; Departamento de Medicina Interna y Nefrología, Universidad de Antioquia, Medellín, Colombia
| | - Lina María Serna-Higuita
- Instituto de Bioestadística y Epidemiología Clínica, Hospital Universitario de Tübingen, Tübingen, Alemania
| | - Lina Arias
- Departamento de Medicina Interna y Nefrología, Universidad de Antioquia, Medellín, Colombia
| | | |
Collapse
|
14
|
Westra D, Volokhina EB, van der Molen RG, van der Velden TJAM, Jeronimus-Klaasen A, Goertz J, Gracchi V, Dorresteijn EM, Bouts AHM, Keijzer-Veen MG, van Wijk JAE, Bakker JA, Roos A, van den Heuvel LP, van de Kar NCAJ. Serological and genetic complement alterations in infection-induced and complement-mediated hemolytic uremic syndrome. Pediatr Nephrol 2017; 32:297-309. [PMID: 27718086 PMCID: PMC5203860 DOI: 10.1007/s00467-016-3496-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND The role of complement in the atypical form of hemolytic uremic syndrome (aHUS) has been investigated extensively in recent years. As the HUS-associated bacteria Shiga-toxin-producing Escherichia coli (STEC) can evade the complement system, we hypothesized that complement dysregulation is also important in infection-induced HUS. METHODS Serological profiles (C3, FH, FI, AP activity, C3d, C3bBbP, C3b/c, TCC, αFH) and genetic profiles (CFH, CFI, CD46, CFB, C3) of the alternative complement pathway were prospectively determined in the acute and convalescent phase of disease in children newly diagnosed with STEC-HUS or aHUS. Serological profiles were compared with those of 90 age-matched controls. RESULTS Thirty-seven patients were studied (26 STEC-HUS, 11 aHUS). In 39 % of them, including 28 % of STEC-HUS patients, we identified a genetic and/or acquired complement abnormality. In all patient groups, the levels of investigated alternative pathway (AP) activation markers were elevated in the acute phase and normalized in remission. The levels were significantly higher in aHUS than in STEC-HUS patients. CONCLUSIONS In both infection-induced HUS and aHUS patients, complement is activated in the acute phase of the disease but not during remission. The C3d/C3 ratio displayed the best discrepancy between acute and convalescent phase and between STEC-HUS and aHUS and might therefore be used as a biomarker in disease diagnosis and monitoring. The presence of aberrations in the alternative complement pathway in STEC-HUS patients was remarkable, as well.
Collapse
Affiliation(s)
- Dineke Westra
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - Elena B Volokhina
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Renate G van der Molen
- Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Thea J A M van der Velden
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Annelies Jeronimus-Klaasen
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Joop Goertz
- Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Valentina Gracchi
- Department of Pediatric Nephrology, University Medical Center Groningen, Groningen, The Netherlands
| | - Eiske M Dorresteijn
- Department of Pediatric Nephrology, Erasmus MC - Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Antonia H M Bouts
- Department of Pediatric Nephrology, Academic Medical Center, Amsterdam, The Netherlands
| | - Mandy G Keijzer-Veen
- Department of Pediatric Nephrology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Joanna A E van Wijk
- Department of Pediatric Nephrology, VU University Medical Center, Amsterdam, The Netherlands
| | - Jaap A Bakker
- Department of Clinical Chemistry and Laboratory Medicine, Leiden University Medical Centre, Leiden, The Netherlands
| | - Anja Roos
- Department of Medical Microbiology and Immunology, Sint Antonius Hospital, Nieuwegein, The Netherlands
| | - Lambert P van den Heuvel
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
- Department of Pediatrics, Department of Growth and Regeneration, University Hospital Leuven, Leuven, Belgium
| | - Nicole C A J van de Kar
- Department of Pediatric Nephrology (804), Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| |
Collapse
|
15
|
Deville C, Garrouste C, Coppo P, Evrard B, Lautrette A, Heng AE. Efficacy of rituximab and plasmapharesis in an adult patient with antifactor H autoantibody-associated hemolytic uremic syndrome: A case report and literature review. Medicine (Baltimore) 2016; 95:e5007. [PMID: 27684863 PMCID: PMC5265956 DOI: 10.1097/md.0000000000005007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Antifactor H antibody (anti-CFHAb) is found in 6% to 25% cases of atypical hemolytic uremic syndrome (aHUS) in children, but has been only exceptionally reported in adults. There is no consensus about the best treatment for this type of aHUS. We report the case of an adult patient treated successfully with plasma exchange (PE), steroids, and rituximab.A 27-year-old Caucasian male presented to hospital with anemia, thrombocytopenia, and acute renal failure. One week earlier, he had digestive problems with diarrhea. The diagnosis of anti-CFHAb-associated aHUS (82,000 AU/mL) without CFHR gene mutations was established.He received Rituximab 375 mg/m (4 pulses) with PE and steroids. This treatment achieved renal and hematological remission at day (D) 31 and negative anti-CFHAb at D45 (<100 AU/mL). At D76, a fifth rituximab pulse was performed while CD19 was higher than 10/mm. Steroids were stopped at month (M) 9. The patient has not relapsed during long-term follow-up (M39).Rituximab therapy can be considered for anti-CFHAb-associated aHUS. Monitoring of anti-CFHAb titer may help to guide maintenance therapeutic strategies including Rituximab infusion.
Collapse
Affiliation(s)
- Clemence Deville
- CHU Clermont-Ferrand, Service de Néphrologie, Pôle REUNNIRH, Clermont-Ferrand
| | - Cyril Garrouste
- CHU Clermont-Ferrand, Service de Néphrologie, Pôle REUNNIRH, Clermont-Ferrand
- Correspondence: Dr Cyril Garrouste, Department of Nephrology, Clermont-Ferrand University Hospital, CHU Gabriel Montpied, 58 Rue Montalembert, 63003 Clermont-Ferrand, France (e-mail: )
| | - Paul Coppo
- CHU Paris Est, Hôpital Saint-Antoine, Service d’Hématologie, AP-HP
- Centre de Référence des Microangiopathies Thrombotiques
- Université Pierre et Marie Curie UPMC Université Paris 6, Paris
| | | | - Alexandre Lautrette
- CHU Clermont-Ferrand, Service de Réanimation, Pôle REUNNIRH, Clermont-Ferrand, France
| | - Anne Elisabeth Heng
- CHU Clermont-Ferrand, Service de Néphrologie, Pôle REUNNIRH, Clermont-Ferrand
| |
Collapse
|
16
|
Riedl M, Hofer J, Giner T, Rosales A, Häffner K, Simonetti GD, Walden U, Maier T, Heininger D, Jeller V, Weiss G, van den Heuvel L, Zimmerhackl LB, Würzner R, Jungraithmayr TC. Novel biomarker and easy to perform ELISA for monitoring complement inhibition in patients with atypical hemolytic uremic syndrome treated with eculizumab. J Immunol Methods 2016; 435:60-7. [PMID: 27238216 DOI: 10.1016/j.jim.2016.05.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 04/27/2016] [Accepted: 05/24/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Magdalena Riedl
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Johannes Hofer
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Thomas Giner
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Alejandra Rosales
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Karsten Häffner
- Department of Pediatric Nephrology, University Hospital Freiburg, Mathildenstraße 1, 79106 Freiburg, Germany
| | - Giacomo D Simonetti
- Department of Pediatric Nephrology, Children's Hospital, University of Bern, Freiburgstraße 18, 3010 Bern, Switzerland
| | - Ulrike Walden
- Department of Pediatric Nephrology, Children's Hospital Augsburg, Stenglinstraße 2, 86156 Augsburg, Germany
| | - Tanja Maier
- Department of Nephrology, Philipps-University Marburg, Baldingerstraße, 35033 Marburg, Germany
| | - Dorothea Heininger
- Department of Internal Medicine IV-Nephrology and Hypertension, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Verena Jeller
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine VI-Infectious Diseases, Immunology, Rheumatology, Pneumology, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Lambert van den Heuvel
- Laboratory of Pediatric Nephrology, Department of Development & Regeneration, KU Leuven, 3000 Leuven, Belgium; Department of Pediatric Nephrology, Radboud University Medical Center, Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, Netherlands
| | - Lothar B Zimmerhackl
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| | - Reinhard Würzner
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Schöpfstraße 41, 6020 Innsbruck, Austria.
| | - Therese C Jungraithmayr
- Department of Pediatrics, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
| |
Collapse
|
17
|
Peyvandi F, Rossio R, Ferrari B, Lotta LA, Pontiggia S, Ghiringhelli Borsa N, Pizzuti M, Donadelli R, Piras R, Cugno M, Noris M. Thrombotic microangiopathy without renal involvement: two novel mutations in complement-regulator genes. J Thromb Haemost 2016; 14:340-5. [PMID: 26613809 DOI: 10.1111/jth.13210] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Indexed: 01/01/2023]
Abstract
UNLABELLED ESSENTIALS: The differential diagnosis among thrombotic microangiopathies (TMAs) is challenging. We studied a case of TMA with neurologic symptoms, no renal impairment and normal ADAMTS-13 levels. Two novel mutations in complement factor I and thrombomodulin genes were identified. Complement-regulator genes can be involved in TMAs with normal ADAMTS-13 regardless of renal damage. BACKGROUND Thrombotic microangiopathies (TMAs) often represent a challenge for clinicians, because clinical, laboratory, and even genetic features are not always sufficient to distinguish among different TMAs. OBJECTIVES The aim of this study was to investigate the pathogenetic mechanisms underlying an acute case of TMA with features of both thrombotic thrombocytopenic purpura (TTP) and atypical hemolytic uremic syndrome (aHUS). PATIENTS/METHODS We report the case of a 49-year-old woman who developed an acute TMA with neurologic involvement and no renal impairment. ADAMTS-13, von Willebrand factor, and complement-system biochemical characterization was performed on acute phase samples. Exome sequencing and direct Sanger sequencing of previously aHUS-associated genes were performed. The functional consequences of the thrombomodulin (THBD) mutation were investigated by in vitro expression studies. RESULTS Despite a clinical diagnosis of TTP, the patient had normal ADAMTS-13 levels and increased VWF antigen levels with ultra-large von Willebrand factor multimers. C3, C4, and complement factors H and I (CFI) were normal. Molecular analysis confirmed two novel heterozygous mutations in CFI (c.805G>A, p.G269S) and THBD (c.1103C>T, p.P368L), and in vitro expression studies showed a reduction in the generation of activated thrombin-activatable fibrinolysis inhibitor (TAFIa) caused by mutated THBD. This proinflammatory condition, associated with the p.G269S mutation in CFI, probably leads to a complement-mediated endothelial activation, with a relevant prothrombotic potential in case of transient environmental triggers. CONCLUSIONS This study identified the first case of acute TMA without renal involvement but with neurological damage carrying two novel mutations in complement-regulator genes, highlighting the possible role of the complement system as a common pathogenetic mechanism in TMAs.
Collapse
Affiliation(s)
- F Peyvandi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - R Rossio
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
| | - B Ferrari
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
| | - L A Lotta
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
| | - S Pontiggia
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
| | - N Ghiringhelli Borsa
- Molecular Otolaryngology and Renal Research Laboratories, University of Iowa, Iowa City, IA, USA
| | - M Pizzuti
- Unit of Hematology, San Carlo Hospital, Potenza, Italy
| | - R Donadelli
- IRCCS - Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Center for Rare Diseases "Aldo e Cele Daccò", Ranica, Bergamo, Italy
| | - R Piras
- IRCCS - Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Center for Rare Diseases "Aldo e Cele Daccò", Ranica, Bergamo, Italy
| | - M Cugno
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Centre, Milan, Italy
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - M Noris
- IRCCS - Istituto di Ricerche Farmacologiche "Mario Negri", Clinical Research Center for Rare Diseases "Aldo e Cele Daccò", Ranica, Bergamo, Italy
| |
Collapse
|
18
|
Yoshida Y, Miyata T, Matsumoto M, Shirotani-Ikejima H, Uchida Y, Ohyama Y, Kokubo T, Fujimura Y. A novel quantitative hemolytic assay coupled with restriction fragment length polymorphisms analysis enabled early diagnosis of atypical hemolytic uremic syndrome and identified unique predisposing mutations in Japan. PLoS One 2015; 10:e0124655. [PMID: 25951460 PMCID: PMC4423893 DOI: 10.1371/journal.pone.0124655] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 03/17/2015] [Indexed: 01/19/2023] Open
Abstract
For thrombotic microangiopathies (TMAs), the diagnosis of atypical hemolytic uremic syndrome (aHUS) is made by ruling out Shiga toxin-producing Escherichia coli (STEC)-associated HUS and ADAMTS13 activity-deficient thrombotic thrombocytopenic purpura (TTP), often using the exclusion criteria for secondary TMAs. Nowadays, assays for ADAMTS13 activity and evaluation for STEC infection can be performed within a few hours. However, a confident diagnosis of aHUS often requires comprehensive gene analysis of the alternative complement activation pathway, which usually takes at least several weeks. However, predisposing genetic abnormalities are only identified in approximately 70% of aHUS. To facilitate the diagnosis of complement-mediated aHUS, we describe a quantitative hemolytic assay using sheep red blood cells (RBCs) and human citrated plasma, spiked with or without a novel inhibitory anti-complement factor H (CFH) monoclonal antibody. Among 45 aHUS patients in Japan, 24% (11/45) had moderate-to-severe (≥50%) hemolysis, whereas the remaining 76% (34/45) patients had mild or no hemolysis (<50%). The former group is largely attributed to CFH-related abnormalities, and the latter group has C3-p.I1157T mutations (16/34), which were identified by restriction fragment length polymorphism (RFLP) analysis. Thus, a quantitative hemolytic assay coupled with RFLP analysis enabled the early diagnosis of complement-mediated aHUS in 60% (27/45) of patients in Japan within a week of presentation. We hypothesize that this novel quantitative hemolytic assay would be more useful in a Caucasian population, who may have a higher proportion of CFH mutations than Japanese patients.
Collapse
Affiliation(s)
- Yoko Yoshida
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
| | - Toshiyuki Miyata
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Masanori Matsumoto
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
| | | | - Yumiko Uchida
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Yoshifumi Ohyama
- Molecular and Cellular Biology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| | - Tetsuro Kokubo
- Molecular and Cellular Biology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| | - Yoshihiro Fujimura
- Department of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan
- * E-mail:
| |
Collapse
|
19
|
Martínez-Barricarte R, Heurich M, López-Perrote A, Tortajada A, Pinto S, López-Trascasa M, Sánchez-Corral P, Morgan BP, Llorca O, Harris CL, Rodríguez de Córdoba S. The molecular and structural bases for the association of complement C3 mutations with atypical hemolytic uremic syndrome. Mol Immunol 2015; 66:263-73. [PMID: 25879158 PMCID: PMC4503813 DOI: 10.1016/j.molimm.2015.03.248] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 03/18/2015] [Accepted: 03/24/2015] [Indexed: 01/28/2023]
Abstract
Mutations in C3 have been associated with aHUS and other glomerulopathies. aHUS-associated C3 mutants R592W, R161W, and I1157T impair regulation by MCP, but not by FH. EM analysis provides the structural basis for the functional impairment of the R161W and I1157T mutants. Data supports aHUS-associated C3 mutations selectively affect complement regulation on surfaces.
Atypical hemolytic uremic syndrome (aHUS) associates with complement dysregulation caused by mutations and polymorphisms in complement activators and regulators. However, the reasons why some mutations in complement proteins predispose to aHUS are poorly understood. Here, we have investigated the functional consequences of three aHUS-associated mutations in C3, R592W, R161W and I1157T. First, we provide evidence that penetrance and disease severity for these mutations is modulated by inheritance of documented “risk” haplotypes as has been observed with mutations in other complement genes. Next, we show that all three mutations markedly reduce the efficiency of factor I-mediated C3b cleavage when catalyzed by membrane cofactor protein (MCP), but not when catalyzed by factor H. Biacore analysis showed that each mutant C3b bound sMCP (recombinant soluble MCP; CD46) at reduced affinity, providing a molecular basis for its reduced cofactor activity. Lastly, we show by electron microscopy structural analysis a displacement of the TED domain from the MG ring in C3b in two of the C3 mutants that explains these defects in regulation. As a whole our data suggest that aHUS-associated mutations in C3 selectively affect regulation of complement on surfaces and provide a structural framework to predict the functional consequences of the C3 genetic variants found in patients.
Collapse
Affiliation(s)
- Rubén Martínez-Barricarte
- Centro Investigaciones Biológicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; Ciber de Enfermedades Raras, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Meike Heurich
- Institute of Infection & Immunity, School of Medicine, Cardiff University Heath Park, Cardiff CF14 4XN, United Kingdom
| | | | - Agustin Tortajada
- Centro Investigaciones Biológicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; Ciber de Enfermedades Raras, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Sheila Pinto
- Centro Investigaciones Biológicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; Ciber de Enfermedades Raras, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Margarita López-Trascasa
- Unidad de Inmunología, Hospital Universitario La Paz-IdiPAZ, and Ciber de Enfermedades Raras. Paseo de la Castellana 261, 28046 Madrid, Spain
| | - Pilar Sánchez-Corral
- Unidad de Investigación, Hospital Universitario La Paz-IdiPAZ, and Ciber de Enfermedades Raras. Paseo de la Castellana 261, 28046 Madrid, Spain
| | - B Paul Morgan
- Institute of Infection & Immunity, School of Medicine, Cardiff University Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Oscar Llorca
- Centro Investigaciones Biológicas, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Claire L Harris
- Institute of Infection & Immunity, School of Medicine, Cardiff University Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Santiago Rodríguez de Córdoba
- Centro Investigaciones Biológicas, Ramiro de Maeztu 9, 28040 Madrid, Spain; Ciber de Enfermedades Raras, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| |
Collapse
|
20
|
Yoshida Y, Matsumoto M. [Atypical HUS caused by complement-related abnormalities]. Rinsho Ketsueki 2015; 56:185-193. [PMID: 25765799 DOI: 10.11406/rinketsu.56.185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The term aHUS was historically used to distinguish this disorder from Shiga-toxin producing Escherichia coli (STEC)-HUS. Many aHUS cases (approximately 70%) are reportedly caused by uncontrolled complement activation due to genetic mutations in the alternative pathway, including complement factor H (CFH), complement factor I (CFI), membrane cofactor protein (MCP), thrombomodulin (THBD), complement component C3 (C3), and complement factor B (CFB). Mutations in the coagulation pathway, such as diacylglycerol kinase ε (DGKE) and plasminogen, are also reported to be causes of aHUS. In this review, we have focused on aHUS due to complement dysfunction. aHUS is suspected based on plasma ADAMTS13 activity of 10% or more, and being negative for STEC-HUS, in addition to the aforementioned triad. Complement genetic studies provide a more specific diagnosis of aHUS. Plasma therapy is the first-line treatment for patients with aHUS and should be initiated as soon as the diagnosis is suspected. Recently, eculizumab, a humanized monoclonal antibody against C5, was shown to be an effective treatment for aHUS. Therefore, early diagnosis and identification of the underlying pathogenic mechanism is important for improving the outcome of aHUS.
Collapse
Affiliation(s)
- Yoko Yoshida
- Department of Blood Transfusion Medicine, Nara Medical University
| | | |
Collapse
|
21
|
Abstract
Complement is increasingly being recognized as an important driver of human disease, including many hemolytic anemias. Paroxysmal nocturnal hemoglobinuria (PNH) cells are susceptible to hemolysis because of a loss of the complement regulatory proteins CD59 and CD55. Patients with atypical hemolytic uremic syndrome (aHUS) develop a thrombotic microangiopathy (TMA) that in most cases is attributable to mutations that lead to activation of the alternative pathway of complement. For optimal therapy, it is critical, but often difficult, to distinguish aHUS from other TMAs, such as thrombotic thrombocytopenic purpura; however, novel bioassays are being developed. In cold agglutinin disease (CAD), immunoglobulin M autoantibodies fix complement on the surface of red cells, resulting in extravascular hemolysis by the reticuloendothelial system. Drugs that inhibit complement activation are increasingly being used to treat these diseases. This article discusses the pathophysiology, diagnosis, and therapy for PNH, aHUS, and CAD.
Collapse
Affiliation(s)
- Robert A Brodsky
- Division of Hematology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| |
Collapse
|
22
|
Sawai T, Okudo Y, Sakai T. [Eculizumab treatment of atypical hemolytic uremic syndrome]. Nihon Jinzo Gakkai Shi 2014; 56:1090-1096. [PMID: 25420410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
|