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Hallam TM, Andreadi A, Sharp SJ, Brocklebank V, Gardenal E, Dreismann A, Lotery AJ, Marchbank KJ, Harris CL, Jones AV, Kavanagh D. Comprehensive functional characterization of Complement factor I rare variant genotypes identified in the SCOPE Geographic Atrophy cohort. J Biol Chem 2024:107452. [PMID: 38852887 DOI: 10.1016/j.jbc.2024.107452] [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: 04/10/2024] [Revised: 05/24/2024] [Accepted: 05/27/2024] [Indexed: 06/11/2024] Open
Abstract
Rare variants (RVs) in the gene encoding the regulatory enzyme complement factor I (CFI; FI) that reduce protein function or levels increase age-related macular degeneration (AMD) risk. A total of 3357 subjects underwent screening in the SCOPE natural history study for Geographic Atrophy (GA) secondary to AMD, including CFI sequencing followed by serum FI measurement. Eleven CFI RV genotypes that were challenging to categorise as Type I (low serum level) or Type II (normal serum level but reduced enzymatic function) were characterized in the context of pure FI protein in C3b and C4b fluid phase cleavage assays and a novel bead-based functional assay (BBFA) of surface-bound C3b cleavage. A further 4 variants predicted or previously characterized as benign, were analysed using the BBFA to add confidence to their classification. In all, 3 variants [W51S, C67R, I370T] resulted in low expression. A further 4 variants [P64L, R339Q, G527V and P528T] were identified as being highly deleterious with IC50s for C3b breakdown >1 log increased vs the WT protein, while 2 variants [K476E and R474Q] were ∼1 log reduced in function. Meanwhile, 6 variants [P50A, T203I, K441R, E548Q, P553S, S570T] had IC50s similar to wild-type (WT). Odds ratios (ORs) and BBFA IC50s were positively correlated (r=0.76, P<0.01), whilst ORs vs combined annotation dependent depletion (CADD) scores were not (r=0.43, P=0.16). Overall, 15 CFI RVs were functionally characterized which may aid future patient stratification approaches for complement-targeted therapies. Pure protein in vitro analysis remains the gold standard for determining the functional consequence of CFI RVs.
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Affiliation(s)
- Thomas M Hallam
- Gyroscope Therapeutics Limited, A Novartis Company, London, UK.
| | - Anneliza Andreadi
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK; National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - Scott J Sharp
- Gyroscope Therapeutics Limited, A Novartis Company, London, UK
| | - Vicky Brocklebank
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK; National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | | | - Anna Dreismann
- Gyroscope Therapeutics Limited, A Novartis Company, London, UK
| | - Andrew J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University Hospital Southampton, University of Southampton, Southampton, United Kingdom
| | - Kevin J Marchbank
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK; National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - Claire L Harris
- Gyroscope Therapeutics Limited, A Novartis Company, London, UK; Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Amy V Jones
- Gyroscope Therapeutics Limited, A Novartis Company, London, UK
| | - David Kavanagh
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK; National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK; Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom.
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Schwotzer N, Fakhouri F, Martins PV, Delmas Y, Caillard S, Zuber J, Moranne O, Mesnard L, Frémeaux-Bacchi V, El-Sissy C. Hot Spot of Complement Factor I Rare Variant p.Ile357Met in Patients With Hemolytic Uremic Syndrome. Am J Kidney Dis 2024:S0272-6386(24)00623-1. [PMID: 38423159 DOI: 10.1053/j.ajkd.2023.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 11/21/2023] [Accepted: 12/23/2023] [Indexed: 03/02/2024]
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare kidney disease due to a dysregulation of the complement alternative pathway. Complement factor I (CFI) negatively regulates the alternative pathway and CFI gene rare variants have been associated to aHUS with a low disease penetrance. We report 10 unrelated cases of HUS associated to a rare CFI variant, p.Ile357Met (c.1071T>G). All patients with isolated p.Ile357Met CFI missense variant were retrospectively identified among patients included between January 2007 and January 2022 in the French HUS Registry. We identified 10 unrelated patients (70% women; median age at HUS diagnosis, 36.5 years) who carry the same rare variant p.Ile357Met in the CFI gene. Seven patients (cases 1-7) presented with aHUS in the native kidney associated with malignant hypertension in 5 patients. None received a C5 inhibitor. Two of these cases occurred in the peripartum period with complete recovery of kidney function, while 5 of these patients reached kidney failure requiring replacement therapy (KFRT). Four patients with KFRT subsequently underwent kidney transplantation. Three later developed C3 glomerulopathy in their kidney graft, but none had aHUS recurrence. Three other patients (cases 8-10) experienced de novo thrombotic microangiopathy after kidney transplantation, precipitated by various triggers. The rare CFI variant p.Ile357Met appears to be a facilitating genetic factor for HUS and for some forms of secondary HUS.
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Affiliation(s)
- Nora Schwotzer
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
| | - Fadi Fakhouri
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Paula Vieira Martins
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Paris, France; Paris University, Paris, France
| | - Yahsou Delmas
- Nephrology Department, CHU de Bordeaux Bordeaux, France
| | - Sophie Caillard
- Nephrology Department, Strasbourg University Hospital, Strasbourg, France
| | - Julien Zuber
- Department of Renal and Metabolic Diseases, Transplantation, and Clinical Immunology Assistance Publique-Hôpitaux de Paris, Hôpital Necker, Paris, France
| | - Olivier Moranne
- Department of Nephrology, Dialysis and Apheresis, Nîmes Hôpital Universitaire, Nîmes, France
| | - Laurent Mesnard
- Sorbonne Université, Paris, France; Nephrology Intensive Care Unit, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Véronique Frémeaux-Bacchi
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Paris, France; Paris University, Paris, France; Inflammation, Complement and Cancer Team, Cordeliers Research Center, INSERM Unité Mixte de Recherche (UMR) S1138, Paris, France
| | - Carine El-Sissy
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Paris, France; Paris University, Paris, France
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Chu L, Bi C, Wang C, Zhou H. The Relationship between Complements and Age-Related Macular Degeneration and Its Pathogenesis. J Ophthalmol 2024; 2024:6416773. [PMID: 38205100 PMCID: PMC10776198 DOI: 10.1155/2024/6416773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 06/08/2023] [Accepted: 12/23/2023] [Indexed: 01/12/2024] Open
Abstract
Age-related macular degeneration is a retinal disease that causes permanent loss of central vision in people over the age of 65. Its pathogenesis may be related to mitochondrial dysfunction, inflammation, apoptosis, autophagy, complement, intestinal flora, and lipid disorders. In addition, the patient's genes, age, gender, cardiovascular disease, unhealthy diet, and living habits may also be risk factors for this disease. Complement proteins are widely distributed in serum and tissue fluid. In the early 21st century, a connection was found between the complement cascade and age-related macular degeneration. However, little is known about the effect of complement factors on the pathogenesis of age-related macular degeneration. This article reviews the factors associated with age-related macular degeneration, the relationship between each factor and complement, the related functions, and variants and provides new ideas for the treatment of this disease.
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Affiliation(s)
- Liyuan Chu
- Department of Ophthalmology, China–Japan Union Hospital of Jilin University, Changchun, China
| | - Chaoran Bi
- College of Traditional Chinese Medicine, Hainan Medical University, Haikou, Hainan, China
| | - Caiming Wang
- Department of Ophthalmology, China–Japan Union Hospital of Jilin University, Changchun, China
| | - Hongyan Zhou
- Department of Ophthalmology, China–Japan Union Hospital of Jilin University, Changchun, China
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Meuleman MS, Vieira-Martins P, El Sissy C, Audard V, Baudouin V, Bertrand D, Bridoux F, Louillet F, Dossier C, Esnault V, Jourde-Chiche N, Karras A, Morin MP, Provot F, Remy P, Ribes D, Rousset-Rouviere C, Servais A, Thervet E, Tricot L, Zaidan M, Wynckel A, Zuber J, Le Quintrec M, Frémeaux-Bacchi V, Chauvet S. Rare Variants in Complement Gene in C3 Glomerulopathy and Immunoglobulin-Mediated Membranoproliferative GN. Clin J Am Soc Nephrol 2023; 18:1435-1445. [PMID: 37615951 PMCID: PMC10637453 DOI: 10.2215/cjn.0000000000000252] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 08/17/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND C3 glomerulopathy and idiopathic immunoglobulin-mediated membranoproliferative GN (Ig-MPGN) are rare complement-mediated kidney diseases. Inherited forms of C3 glomerulopathy/Ig-MPGN are rarely described. METHODS Three hundred ninety-eight patients with C3 glomerulopathy ( n =296) or Ig-MPGN ( n =102) from a national registry were screened for three complement genes: factor H ( CFH ), factor I ( CFI ), and C3 . Patients with rare variant (minor allele frequency <0.1%) were included. Epidemiologic, clinical, and immunologic data at diagnosis and kidney outcomes of patients were retrospectively collected. RESULTS Fifty-three different rare variants, including 30 (57%), 13 (24%), and ten (19%) in CFH , CFI , and C3 variants, were identified in 66/398 (17%) patients. Thirty-eight (72%) variants were classified as pathogenic, including 20/30 (66%) and 11/13 (84%) variants in CFH and CFI , respectively, impairing synthesis of factor H or factor I regulators. Fifteen of 53 (27%) variants were of unknown significance. At diagnosis, 69% of patients were adult (median age of 31 years). With the exception of biologic stigma of thrombotic microangiopathy, which was more frequent in patients with CFI variants (5/14 [36%] versus 1/37 [3%] and 0% in the CFH group and C3 group, respectively, P < 0.001), the clinical and histologic features were similar among the three variants groups. The kidney outcome was poor regardless of the age at onset and treatment received. Sixty-five percent (43/66) of patients with rare variant reach kidney failure after a median delay of 41 (19-104) months, compared with 28% (55/195) after a median delay of 34 (12-143) months in the nonvariant group. Among 36 patients who received a kidney transplant, 2-year recurrence was frequent, occurring in 39% (12/31), without difference between variant groups, and led to graft failure in three cases. CONCLUSIONS In our cohort, 17% of C3 glomerulopathy/Ig-MPGN cases were associated with rare variants in the CFH , CFI , or C3 genes. In most cases, a quantitative deficiency in factor H or factor I was identified. The presence of a rare variant was associated with poor kidney survival. PODCAST This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_11_08_CJN0000000000000252.mp3.
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Affiliation(s)
- Marie Sophie Meuleman
- Team “Inflammation, Complement and Cancer,” INSERM UMRS1138, Centre de Recherche des Cordeliers, Paris, France
| | - Paula Vieira-Martins
- Department of Immunology Biology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
| | - Carine El Sissy
- Team “Inflammation, Complement and Cancer,” INSERM UMRS1138, Centre de Recherche des Cordeliers, Paris, France
- Department of Immunology Biology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
| | - Vincent Audard
- Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Henri-Mondor Hospital, Créteil, France
- INSERM U955, Institut Mondor de Recherche Biomédicale (IMRB), Créteil, France
| | - Véronique Baudouin
- Department of Pediatric Nephrology, Assistance Publique-Hôpitaux de Paris, Robert Debré University Hospital, Paris, France
| | | | - Frank Bridoux
- Department of Nephrology, Poitiers University Hospital, Poitiers, France
| | | | - Claire Dossier
- Department of Pediatric Nephrology, Assistance Publique-Hôpitaux de Paris, Robert Debré University Hospital, Paris, France
| | - Vincent Esnault
- Department of Nephrology, Nice University Hospital, Nice, France
| | - Noémie Jourde-Chiche
- Department of Nephrology, Assistance Publique-Hôpitaux de Marseille, CHU Conception, Marseille, France
- INSERM, INRAE, C2VN, Aix-Marseille University, Marseille, France
| | - Alexandre Karras
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
| | | | - François Provot
- Department of Nephrology, Lille University Hospital, Lille, France
| | - Philippe Remy
- Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Henri-Mondor Hospital, Créteil, France
| | - David Ribes
- Department of Nephrology, Toulouse University Hospital, Toulouse, France
| | - Caroline Rousset-Rouviere
- Department of Pediatric Nephrology, Assistance Publique-Hôpitaux de Marseille, Timone Hospital, Marseille, France
| | - Aude Servais
- Department of Nephrology and Renal Transplantation, Assistance Publique-Hôpitaux de Paris, Necker Hospital, Paris, France
| | - Eric Thervet
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
| | - Leila Tricot
- Department of Nephrology, Foch Hospital, Suresnes, France
| | - Mohamad Zaidan
- Department of Nephrology and Renal Transplantation, Assistance Publique-Hôpitaux de Paris, Bicetre Hospital, Le Kremlin-Bicêtre, France
| | - Alain Wynckel
- Department of Nephrology, Reims University Hospital, Reims, France
| | - Julien Zuber
- Department of Nephrology and Renal Transplantation, Assistance Publique-Hôpitaux de Paris, Necker Hospital, Paris, France
| | - Moglie Le Quintrec
- Department of Nephrology, Montpellier University Hospital, Montpellier, France
| | - Véronique Frémeaux-Bacchi
- Team “Inflammation, Complement and Cancer,” INSERM UMRS1138, Centre de Recherche des Cordeliers, Paris, France
- Department of Immunology Biology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
| | - Sophie Chauvet
- Team “Inflammation, Complement and Cancer,” INSERM UMRS1138, Centre de Recherche des Cordeliers, Paris, France
- Department of Nephrology, Assistance Publique-Hôpitaux de Paris, European Hospital Georges Pompidou, Paris, France
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5
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Acar IE, Galesloot TE, Luhmann UFO, Fauser S, Gayán J, den Hollander AI, Nogoceke E. Whole Genome Sequencing Identifies Novel Common and Low-Frequency Variants Associated With Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2023; 64:24. [PMID: 37975850 PMCID: PMC10664724 DOI: 10.1167/iovs.64.14.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 10/22/2023] [Indexed: 11/19/2023] Open
Abstract
Purpose To identify associations of common, low-frequency, and rare variants with advanced age-related macular degeneration (AMD) using whole genome sequencing (WGS). Methods WGS data were obtained for 2123 advanced AMD patients (participants of clinical trials for advanced AMD) and 2704 controls (participants of clinical trials for asthma [N = 2518] and Alzheimer's disease [N = 186]), and joint genotype calling was performed, followed by quality control of the dataset. Single variant association analyses were performed for all identified common, low-frequency, and rare variants. Gene-based tests were executed for rare and low-frequency variants using SKAT-O and three groups of variants based on putative impact information: (1) all variants, (2) modifier impact variants, and (3) high- and moderate-impact variants. To ascertain independence of the identified associations from previously reported AMD and asthma loci, conditional analyses were performed. Results Previously identified AMD variants at the CFH, ARMS2/HTRA1, APOE, and C3 loci were associated with AMD at a genome-wide significance level. We identified new single variant associations for common variants near the PARK7 gene and in the long non-coding RNA AC103876.1, and for a rare variant near the TENM3 gene. In addition, gene-based association analyses identified a burden of modifier variants in eight intergenic and gene-spanning regions and of high- and moderate-impact variants in the C3, CFHR5, SLC16A8, and CFI genes. Conclusions We describe the largest WGS study in AMD to date. We confirmed previously identified associations and identified several novel associations that are worth exploring in further follow-up studies.
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Affiliation(s)
- Ilhan E. Acar
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Tessel E. Galesloot
- Radboud University Medical Center, Radboud Institute for Health Sciences, Department for Health Evidence, Nijmegen, The Netherlands
| | - Ulrich F. O. Luhmann
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Sascha Fauser
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Javier Gayán
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Anneke I. den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Everson Nogoceke
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
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6
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Gerogianni A, Baas LM, Sjöström DJ, van de Kar NCAJ, Pullen M, van de Peppel SJ, Nilsson PH, van den Heuvel LP. Functional evaluation of complement factor I variants by immunoassays and SDS-PAGE. Front Immunol 2023; 14:1279612. [PMID: 37954579 PMCID: PMC10639126 DOI: 10.3389/fimmu.2023.1279612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 10/16/2023] [Indexed: 11/14/2023] Open
Abstract
Factor I (FI) is an essential regulator of the complement system. Together with co-factors, FI degrades C3b, which inhibits further complement activation. Genetic mutations in FI are associated with pathological conditions like age-related macular degeneration and atypical hemolytic uremic syndome. Here, we evaluated eight recombinant FI genetic variants found in patients. We assessed FI's co-factor activity in the presence of two co-factors; Factor H and soluble CR1. Different analytical assays were employed; SDS-PAGE to evaluate the degradation of C3b, ELISA to measure the generation of fluid phase iC3b and the degradation of surface-bound C3b using a novel Luminex bead-based assay. We demonstrate that mutations in the FIMAC and SP domains of FI led to significantly reduced protease activity, whereas the two analyzed mutations in the LDLRA2 domain did not result in any profound changes in FI's function. The different assays employed displayed a strong positive correlation, but differences in the activity of the genetic variants Ile55Phe and Gly261Asp could only be observed by combining different methods and co-factors for evaluating FI activity. In conclusion, our results provide a new perspective regarding available diagnostic tools for assessing the impact of mutations in FI.
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Affiliation(s)
- Alexandra Gerogianni
- Linnaeus Centre for Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
- Department of Chemistry and Biomedicine, Linnaeus University, Kalmar, Sweden
| | - Laura M. Baas
- Department of Pediatric Nephrology, Radboud University Medical Center, Amalia Children’s Hospital, Nijmegen, Netherlands
| | - Dick J. Sjöström
- Linnaeus Centre for Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
- Department of Chemistry and Biomedicine, Linnaeus University, Kalmar, Sweden
| | - Nicole C. A. J. van de Kar
- Department of Pediatric Nephrology, Radboud University Medical Center, Amalia Children’s Hospital, Nijmegen, Netherlands
| | - Marit Pullen
- Department of Genetics, Radboud University Medical Center, Nijmegen, Netherlands
| | - Siem J. van de Peppel
- Department of Pediatric Nephrology, Radboud University Medical Center, Amalia Children’s Hospital, Nijmegen, Netherlands
| | - Per H. Nilsson
- Linnaeus Centre for Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
- Department of Chemistry and Biomedicine, Linnaeus University, Kalmar, Sweden
| | - Lambertus P. van den Heuvel
- Department of Pediatric Nephrology, Radboud University Medical Center, Amalia Children’s Hospital, Nijmegen, Netherlands
- Department of Genetics, Radboud University Medical Center, Nijmegen, Netherlands
- Department of Pediatrics/Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
- Department of Development and Regeneration, University Hospitals Leuven, Leuven, Belgium
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7
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Rydberg V, Aradottir SS, Kristoffersson AC, Svitacheva N, Karpman D. Genetic investigation of Nordic patients with complement-mediated kidney diseases. Front Immunol 2023; 14:1254759. [PMID: 37744338 PMCID: PMC10513385 DOI: 10.3389/fimmu.2023.1254759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 08/21/2023] [Indexed: 09/26/2023] Open
Abstract
Background Complement activation in atypical hemolytic uremic syndrome (aHUS), C3 glomerulonephropathy (C3G) and immune complex-mediated membranoproliferative glomerulonephritis (IC-MPGN) may be associated with rare genetic variants. Here we describe gene variants in the Swedish and Norwegian populations. Methods Patients with these diagnoses (N=141) were referred for genetic screening. Sanger or next-generation sequencing were performed to identify genetic variants in 16 genes associated with these conditions. Nonsynonymous genetic variants are described when they have a minor allele frequency of <1% or were previously reported as being disease-associated. Results In patients with aHUS (n=94, one also had IC-MPGN) 68 different genetic variants or deletions were identified in 60 patients, of which 18 were novel. Thirty-two patients had more than one genetic variant. In patients with C3G (n=40) 29 genetic variants, deletions or duplications were identified in 15 patients, of which 9 were novel. Eight patients had more than one variant. In patients with IC-MPGN (n=7) five genetic variants were identified in five patients. Factor H variants were the most frequent in aHUS and C3 variants in C3G. Seventeen variants occurred in more than one condition. Conclusion Genetic screening of patients with aHUS, C3G and IC-MPGN is of paramount importance for diagnostics and treatment. In this study, we describe genetic assessment of Nordic patients in which 26 novel variants were found.
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Affiliation(s)
| | | | | | | | - Diana Karpman
- Department of Pediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
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8
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Rolfes M, Harroud A, Zorn KC, Tubati A, Omura C, Kurtz K, Matloubian M, Berger A, Chiu CY, Wilson MR, Ramachandran PS. Complement Factor I Gene Variant as a Treatable Cause of Recurrent Aseptic Neutrophilic Meningitis: A Case Report. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2023; 10:e200121. [PMID: 37339889 DOI: 10.1212/nxi.0000000000200121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/10/2023] [Indexed: 06/22/2023]
Abstract
Mutations in the complement factor I (CFI) gene have previously been identified as causes of recurrent CNS inflammation. We present a case of a 26-year-old man with 18 episodes of recurrent meningitis, who had a variant in CFI(c.859G>A,p.Gly287Arg) not previously associated with neurologic manifestations. He achieved remission with canakinumab, a human monoclonal antibody targeted at interleukin-1 beta.
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Affiliation(s)
- Mary Rolfes
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Adil Harroud
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Kelsey C Zorn
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Asritha Tubati
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Charles Omura
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Kenneth Kurtz
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Mehrdad Matloubian
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Amy Berger
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Charles Y Chiu
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Michael R Wilson
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia
| | - Prashanth S Ramachandran
- From the Weill Institute for Neurosciences (M.R., M.R.W.), Department of Neurology, University of California, San Francisco; Montreal Neurological Institute and Hospital (A.H.), Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Department of Biochemistry and Biophysics (K.C.Z., A.T.); Department of Laboratory Medicine (C.O., C.Y.C.); Kaiser Permanente Santa Rosa Medical Center (K.K.)Department of Medicine (M.M.), Division of Rheumatology; Department of Medicine (A.B.), Molecular Medicine Consult Service; Department of Medicine (C.Y.C.), Division of Infectious Diseases, University of California, San Francisco; The Peter Doherty Institute for Infection and Immunity (P.S.R.); Department of Neurology (P.S.R.), Royal Melbourne Hospital; and Department of Neurology (P.S.R.), St.Vincent's Hospital, University of Melbourne, Australia.
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9
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Hallam TM, Sharp SJ, Andreadi A, Kavanagh D. Complement factor I: Regulatory nexus, driver of immunopathology, and therapeutic. Immunobiology 2023; 228:152410. [PMID: 37478687 DOI: 10.1016/j.imbio.2023.152410] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/23/2023] [Accepted: 06/01/2023] [Indexed: 07/23/2023]
Abstract
Complement factor I (FI) is the nexus for classical, lectin and alternative pathway complement regulation. FI is an 88 kDa plasma protein that circulates in an inactive configuration until it forms a trimolecular complex with its cofactor and substrate whereupon a structural reorganization allows the catalytic triad to cleave its substrates, C3b and C4b. In keeping with its role as the master complement regulatory enzyme, deficiency has been linked to immunopathology. In the setting of complete FI deficiency, a consumptive C3 deficiency results in recurrent infections with encapsulated microorganisms. Aseptic cerebral inflammation and vasculitic presentations are also less commonly observed. Heterozygous mutations in the factor I gene (CFI) have been demonstrated to be enriched in atypical haemolytic uraemic syndrome, albeit with a very low penetrance. Haploinsufficiency of CFI has also been associated with decreased retinal thickness and is a strong risk factor for the development of age-related macular degeneration. Supplementation of FI using plasma purified or recombinant protein has long been postulated, however, technical difficulties prevented progression into clinical trials. It is only using gene therapy that CFI supplementation has reached the clinic with GT005 in phase I/II clinical trials for geographic atrophy.
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Affiliation(s)
- T M Hallam
- Gyroscope Therapeutics Limited, A Novartis Company, Rolling Stock Yard, London N7 9AS, UK; Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK; National Renal Complement Therapeutics Centre, Building 26, Royal Victoria Infirmary, UK
| | - S J Sharp
- Gyroscope Therapeutics Limited, A Novartis Company, Rolling Stock Yard, London N7 9AS, UK
| | - A Andreadi
- Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK; National Renal Complement Therapeutics Centre, Building 26, Royal Victoria Infirmary, UK
| | - D Kavanagh
- Translational and Clinical Research Institute, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK; National Renal Complement Therapeutics Centre, Building 26, Royal Victoria Infirmary, UK; NIHR Newcastle Biomedical Research Centre, Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK.
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10
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Grunin M, de Jong S, Palmer EL, Jin B, Rinker D, Moth C, Capra A, Haines JL, Bush WS, den Hollander AI. Spatial Distribution of Missense Variants within Complement Proteins Associates with Age Related Macular Degeneration. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.08.28.23294686. [PMID: 37693462 PMCID: PMC10491280 DOI: 10.1101/2023.08.28.23294686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Purpose Genetic variants in complement genes are associated with age-related macular degeneration (AMD). However, many rare variants have been identified in these genes, but have an unknown significance, and their impact on protein function and structure is still unknown. We set out to address this issue by evaluating the spatial placement and impact on protein structureof these variants by developing an analytical pipeline and applying it to the International AMD Genomics Consortium (IAMDGC) dataset (16,144 AMD cases, 17,832 controls). Methods The IAMDGC dataset was imputed using the Haplotype Reference Consortium (HRC), leading to an improvement of over 30% more imputed variants, over the original 1000 Genomes imputation. Variants were extracted for the CFH , CFI , CFB , C9 , and C3 genes, and filtered for missense variants in solved protein structures. We evaluated these variants as to their placement in the three-dimensional structure of the protein (i.e. spatial proximity in the protein), as well as AMD association. We applied several pipelines to a) calculate spatial proximity to known AMD variants versus gnomAD variants, b) assess a variant's likelihood of causing protein destabilization via calculation of predicted free energy change (ddG) using Rosetta, and c) whole gene-based testing to test for statistical associations. Gene-based testing using seqMeta was performed using a) all variants b) variants near known AMD variants or c) with a ddG >|2|. Further, we applied a structural kernel adaptation of SKAT testing (POKEMON) to confirm the association of spatial distributions of missense variants to AMD. Finally, we used logistic regression on known AMD variants in CFI to identify variants leading to >50% reduction in protein expression from known AMD patient carriers of CFI variants compared to wild type (as determined by in vitro experiments) to determine the pipeline's robustness in identifying AMD-relevant variants. These results were compared to functional impact scores, ie CADD values > 10, which indicate if a variant may have a large functional impact genomewide, to determine if our metrics have better discriminative power than existing variant assessment methods. Once our pipeline had been validated, we then performed a priori selection of variants using this pipeline methodology, and tested AMD patient cell lines that carried those selected variants from the EUGENDA cohort (n=34). We investigated complement pathway protein expression in vitro , looking at multiple components of the complement factor pathway in patient carriers of bioinformatically identified variants. Results Multiple variants were found with a ddG>|2| in each complement gene investigated. Gene-based tests using known and novel missense variants identified significant associations of the C3 , C9 , CFB , and CFH genes with AMD risk after controlling for age and sex (P=3.22×10 -5 ;7.58×10 -6 ;2.1×10 -3 ;1.2×10 -31 ). ddG filtering and SKAT-O tests indicate that missense variants that are predicted to destabilize the protein, in both CFI and CFH, are associated with AMD (P=CFH:0.05, CFI:0.01, threshold of 0.05 significance). Our structural kernel approach identified spatial associations for AMD risk within the protein structures for C3, C9, CFB, CFH, and CFI at a nominal p-value of 0.05. Both ddG and CADD scores were predictive of reduced CFI protein expression, with ROC curve analyses indicating ddG is a better predictor (AUCs of 0.76 and 0.69, respectively). A priori in vitro analysis of variants in all complement factor genes indicated that several variants identified via bioinformatics programs PathProx/POKEMON in our pipeline via in vitro experiments caused significant change in complement protein expression (P=0.04) in actual patient carriers of those variants, via ELISA testing of proteins in the complement factor pathway, and were previously unknown to contribute to AMD pathogenesis. Conclusion We demonstrate for the first time that missense variants in complement genes cluster together spatially and are associated with AMD case/control status. Using this method, we can identify CFI and CFH variants of previously unknown significance that are predicted to destabilize the proteins. These variants, both in and outside spatial clusters, can predict in-vitro tested CFI protein expression changes, and we hypothesize the same is true for CFH . A priori identification of variants that impact gene expression allow for classification for previously classified as VUS. Further investigation is needed to validate the models for additional variants and to be applied to all AMD-associated genes.
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11
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Java A, Atkinson J, Hu Z, Pozzi N. Mutations in atypical hemolytic uremic syndrome provide evidence for the role of calcium in complement factor I. Blood 2023; 142:607-610. [PMID: 37363824 PMCID: PMC10447607 DOI: 10.1182/blood.2022019361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/29/2023] [Accepted: 04/26/2023] [Indexed: 06/28/2023] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare thrombotic microangiopathy. Genetic variants in complement proteins are found in ≈60% of patients. Of these patients, ≈15% carry mutations in complement factor I (CFI). Factor I (FI) is a multidomain serine protease that cleaves and thereby inactivates C3b and C4b in the presence of cofactor proteins. Crystal structures have shown that FI possesses 2 calcium-binding domains, low-density lipoprotein receptor class A (LDLRA) 1 and LDLRA2. Yet, the role of calcium in FI is unknown. We determined that 9 genetic variants identified in aHUS (N151S, G162D, G188A, V230E, A240G, G243R, C247G, A258T, and Q260D) cluster around the calcium-binding site of LDLRA1. Using site-directed mutagenesis, we established that the synthesis of all, except A258T, was impaired, implying defective protein folding, perhaps due to loss of calcium binding. To further explore this possibility, we generated 12 alanine mutants that coordinate with the calcium in LDLRA1 and LDLRA2 (K239A, D242A, I244A, D246A, D252A, E253A, Y276A, N279A, E281A, D283A, D289A, and D290A) and are expected to perturb calcium binding. Except for K239A and Y276A, none of the mutants was secreted. These observations suggest that calcium ions play key structural and functional roles in FI.
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Affiliation(s)
- Anuja Java
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - John Atkinson
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Zheng Hu
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Nicola Pozzi
- Department of Biochemistry and Molecular Biology, Edward A. Doisy Research Center, Saint Louis University School of Medicine, St. Louis, MO
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12
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Connaughton DM, Bhai P, Isenring P, Mahdi M, Sadikovic B, Schenkel LC. Genotypic analysis of a large cohort of patients with suspected atypical hemolytic uremic syndrome. J Mol Med (Berl) 2023; 101:1029-1040. [PMID: 37466676 PMCID: PMC10400659 DOI: 10.1007/s00109-023-02341-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 06/14/2023] [Accepted: 06/16/2023] [Indexed: 07/20/2023]
Abstract
Atypical hemolytic uremic syndrome (aHUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and renal impairment. Complement and coagulation gene variants have been associated with aHUS susceptibility. We assessed the diagnostic yield of a next-generation sequencing (NGS) panel in a large cohort of Canadian patients with suspected aHUS. Molecular testing was performed on peripheral blood DNA samples from 167 patients, collected between May 2019 and December 2021, using a clinically validated NGS pipeline. Coding exons with 20 base pairs of flanking intronic regions for 21 aHUS-associated or candidate genes were enriched using a custom hybridization protocol. All sequence and copy number variants were assessed and classified following American College of Medical Genetics guidelines. Molecular diagnostic results were reported for four variants in three individuals (1.8%). Twenty-seven variants of unknown significance were identified in 25 (15%) patients, and 34 unique variants in candidate genes were identified in 28 individuals. An illustrative patient case describing two genetic alterations in complement genes is presented, highlighting that variable expressivity and incomplete penetrance must be considered when interpreting genetic data in patients with complement-mediated disease, alongside the potential additive effects of genetic variants on aHUS pathophysiology. In this cohort of patients with suspected aHUS, using clinical pipelines for genetic testing and variant classification, pathogenic/likely pathogenic variants occurred in a very small percentage of patients. Our results highlight the ongoing challenges in variant classification following NGS panel testing in patients with suspected aHUS, alongside the need for clear testing guidance in the clinical setting. KEY MESSAGES: • Clinical molecular testing for disease associated genes in aHUS is challenging. • Challenges include patient selection criteria, test validation, and interpretation. • Most variants were of uncertain significance (31.7% of patients; VUS + candidates). • Their clinical significance may be elucidated as more evidence becomes available. • Low molecular diagnostic rate (1.8%), perhaps due to strict classification criteria. • Case study identified two likely pathogenic variants; one each in MCP/CD46 and CFI.
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Affiliation(s)
- Dervla M Connaughton
- Schulich School of Medicine & Dentistry, University of Western, London, ON, Canada
- Department of Medicine, Division of Nephrology, London Health Sciences Centre, 339 Windermere Road, London, ON, Canada
| | - Pratibha Bhai
- Molecular Genetics Laboratory, Molecular Diagnostics Division, London Health Sciences Centre (LHSC), London, ON, Canada
| | - Paul Isenring
- Faculty of Medicine, Université Laval, Quebec City, QC, Canada
| | | | - Bekim Sadikovic
- Molecular Genetics Laboratory, Molecular Diagnostics Division, London Health Sciences Centre (LHSC), London, ON, Canada
- Pathology and Laboratory Medicine, Western University, London, ON, Canada
| | - Laila C Schenkel
- Molecular Genetics Laboratory, Molecular Diagnostics Division, London Health Sciences Centre (LHSC), London, ON, Canada.
- Pathology and Laboratory Medicine, Western University, London, ON, Canada.
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13
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Farinha C, Barreto P, Coimbra R, Cachulo ML, Melo JB, Cunha-Vaz J, Lechanteur Y, Hoyng CB, Silva R. Common and rare genetic risk variants in age-related macular degeneration and genetic risk score in the Coimbra eye study. Acta Ophthalmol 2023; 101:185-199. [PMID: 36036675 DOI: 10.1111/aos.15232] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/27/2022] [Accepted: 08/14/2022] [Indexed: 12/01/2022]
Abstract
PURPOSE To determine the contribution of common and rare genetic variants in age-related macular degeneration (AMD) in a Portuguese population from the Coimbra Eye Study (CES), and the genetic risk score (GRS). METHODS Participants underwent ophthalmologic examination and imaging. A centralized reading centre performed AMD staging. Genetic sequencing was carried out with the EYE-RISK assay. Sixty-nine single nucleotide polymorphisms (SNPs) were genotyped and tested for association with AMD. Case-control and progression-to-AMD analyses were performed using logistic regression to assess allelic odds ratio (OR) at a 95% confidence interval (CI) for each variant. GRS was calculated for cases/controls and progressors/non-progressors. Cumulative impact of rare variants was compared between cases/controls using logistic regression. RESULTS In case-control analysis (237 cases/640 controls) variants associated with risk of disease were: ARMS2 rs10490924, ARMS2_HTRA1 rs3750846, CFH rs35292876, SLC16A8 rs8135665, TGFBR1 rs1626340. Major risk variants ARMS2/HTRA1 rs3750846, CFH rs570618 and C3 rs2230199 had unexpected lower allele frequency (AF), and the highest risk-conferring variant was a rare variant, CFH rs35292876 (OR, 2.668; p-value = 0.021). In progression-to-AMD analysis (137 progressors/630 non-progressors), variants associated with risk of progression were ARMS2 rs10490924, ARMS2_HTRA1 rs3750846, CFH rs35292876. GRS of cases/controls was 1.124 ± 1.187 and 0.645 ± 1.124 (p-value < 0.001), and of progressors/non-progressors was 1.190 ± 1.178 and 0.669 ± 1.141 (p-value < 0.001). Higher proportion of pathogenic rare CFH variants was observed in cases (OR, 9.661; p-value < 0.001). CONCLUSIONS Both common and rare variants were associated with AMD, but a CFH rare variant conferred the highest risk of disease while three major risk variants had a lower-than-expected AF in our population originary from a geographic region with lower prevalence of AMD. GRS was still significantly higher in AMD patients. Damaging CFH rare variants were cumulatively more common in AMD cases.
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Affiliation(s)
- Cláudia Farinha
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal.,Ophthalmology Department, Coimbra Hospital and Universitary Centre (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, (iCBR- FMUC), University of Coimbra, Coimbra, Portugal
| | - Patricia Barreto
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - Rita Coimbra
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - Maria Luz Cachulo
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal.,Ophthalmology Department, Coimbra Hospital and Universitary Centre (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal
| | - Joana Barbosa Melo
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - José Cunha-Vaz
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal.,Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, (iCBR- FMUC), University of Coimbra, Coimbra, Portugal.,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - Yara Lechanteur
- Department of Ophthalmology, Radboud University Medical Center, Donders Institute for Brain Cognition and Behaviour, Nijmegan, Netherlands
| | - Carel B Hoyng
- Department of Ophthalmology, Radboud University Medical Center, Donders Institute for Brain Cognition and Behaviour, Nijmegan, Netherlands
| | - Rufino Silva
- AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal.,Ophthalmology Department, Coimbra Hospital and Universitary Centre (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, (iCBR- FMUC), University of Coimbra, Coimbra, Portugal.,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
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14
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de Jong S, Tang J, Clark SJ. Age-related macular degeneration: A disease of extracellular complement amplification. Immunol Rev 2023; 313:279-297. [PMID: 36223117 DOI: 10.1111/imr.13145] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Age-related macular degeneration (AMD) is a major cause of vision impairment in the Western World, and with the aging world population, its incidence is increasing. As of today, for the majority of patients, no treatment exists. Multiple genetic and biochemical studies have shown a strong association with components in the complement system and AMD, and evidence suggests a major role of remodeling of the extracellular matrix underlying the outer blood/retinal barrier. As part of the innate immune system, the complement cascade acts as a first-line defense against pathogens, and upon activation, its amplification loop ensures a strong, rapid, and sustained response. Excessive activation, however, can lead to host tissue damage and cause complement-associated diseases like AMD. AMD patients present with aberrant activation of the alternative pathway, especially in ocular tissues but also on a systemic level. Here, we review the latest findings of complement activation in AMD, and we will discuss in vivo observations made in human tissue, cellular models, the potential synergy of different AMD-associated pathways, and conclude on current clinical trials and the future outlook.
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Affiliation(s)
- Sarah de Jong
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.,Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Jiaqi Tang
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.,Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Simon J Clark
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.,Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany.,Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
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15
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den Hollander AI, Mullins RF, Orozco LD, Voigt AP, Chen HH, Strunz T, Grassmann F, Haines JL, Kuiper JJW, Tumminia SJ, Allikmets R, Hageman GS, Stambolian D, Klaver CCW, Boeke JD, Chen H, Honigberg L, Katti S, Frazer KA, Weber BHF, Gorin MB. Systems genomics in age-related macular degeneration. Exp Eye Res 2022; 225:109248. [PMID: 36108770 PMCID: PMC10150562 DOI: 10.1016/j.exer.2022.109248] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 08/29/2022] [Accepted: 09/07/2022] [Indexed: 12/29/2022]
Abstract
Genomic studies in age-related macular degeneration (AMD) have identified genetic variants that account for the majority of AMD risk. An important next step is to understand the functional consequences and downstream effects of the identified AMD-associated genetic variants. Instrumental for this next step are 'omics' technologies, which enable high-throughput characterization and quantification of biological molecules, and subsequent integration of genomics with these omics datasets, a field referred to as systems genomics. Single cell sequencing studies of the retina and choroid demonstrated that the majority of candidate AMD genes identified through genomic studies are expressed in non-neuronal cells, such as the retinal pigment epithelium (RPE), glia, myeloid and choroidal cells, highlighting that many different retinal and choroidal cell types contribute to the pathogenesis of AMD. Expression quantitative trait locus (eQTL) studies in retinal tissue have identified putative causal genes by demonstrating a genetic overlap between gene regulation and AMD risk. Linking genetic data to complement measurements in the systemic circulation has aided in understanding the effect of AMD-associated genetic variants in the complement system, and supports that protein QTL (pQTL) studies in plasma or serum samples may aid in understanding the effect of genetic variants and pinpointing causal genes in AMD. A recent epigenomic study fine-mapped AMD causal variants by determing regulatory regions in RPE cells differentiated from induced pluripotent stem cells (iPSC-RPE). Another approach that is being employed to pinpoint causal AMD genes is to produce synthetic DNA assemblons representing risk and protective haplotypes, which are then delivered to cellular or animal model systems. Pinpointing causal genes and understanding disease mechanisms is crucial for the next step towards clinical translation. Clinical trials targeting proteins encoded by the AMD-associated genomic loci C3, CFB, CFI, CFH, and ARMS2/HTRA1 are currently ongoing, and a phase III clinical trial for C3 inhibition recently showed a modest reduction of lesion growth in geographic atrophy. The EYERISK consortium recently developed a genetic test for AMD that allows genotyping of common and rare variants in AMD-associated genes. Polygenic risk scores (PRS) were applied to quantify AMD genetic risk, and may aid in predicting AMD progression. In conclusion, genomic studies represent a turning point in our exploration of AMD. The results of those studies now serve as a driving force for several clinical trials. Expanding to omics and systems genomics will further decipher function and causality from the associations that have been reported, and will enable the development of therapies that will lessen the burden of AMD.
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Affiliation(s)
- Anneke I den Hollander
- Department of Ophthalmology, Radboud University Medical Center, Nijmegen, the Netherlands; AbbVie, Genomics Research Center, Cambridge, MA, USA.
| | - Robert F Mullins
- The University of Iowa Institute for Vision Research, Iowa City, IA, USA; Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | | | - Andrew P Voigt
- The University of Iowa Institute for Vision Research, Iowa City, IA, USA; Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | | | - Tobias Strunz
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany
| | | | - Jonathan L Haines
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, USA; Cleveland Institute for Computational Biology, Case Western Reserve University, Cleveland, OH, USA
| | - Jonas J W Kuiper
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands; Center of Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Rando Allikmets
- Department of Ophthalmology, Columbia University, NY, USA; Department of Pathology and Cell Biology, Columbia University, NY, USA
| | - Gregory S Hageman
- Sharon Eccles Steele Center for Translational Medicine, John A. Moran Eye Center, Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, UT, USA
| | - Dwight Stambolian
- Departments of Ophthalmology and Human Genetics, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Caroline C W Klaver
- Department of Ophthalmology, Radboud University Medical Center, Nijmegen, the Netherlands; Departments of Ophthalmology and Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands; Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Jef D Boeke
- Institute for Systems Genetics, NYU Langone Health, NY, USA; Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, NY, USA; Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, USA
| | - Hao Chen
- Genentech, South San Francisco, CA, USA
| | | | | | - Kelly A Frazer
- Department of Pediatrics, University of California, San Diego, La Jolla, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, USA
| | - Bernhard H F Weber
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany; Institute of Clinical Human Genetics, University Hospital Regensburg, Regensburg, Germany
| | - Michael B Gorin
- Departments of Ophthalmology and Human Genetics, University of California, Los Angeles, CA, USA
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Shughoury A, Sevgi DD, Ciulla TA. Molecular Genetic Mechanisms in Age-Related Macular Degeneration. Genes (Basel) 2022; 13:genes13071233. [PMID: 35886016 PMCID: PMC9316037 DOI: 10.3390/genes13071233] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 11/29/2022] Open
Abstract
Age-related macular degeneration (AMD) is among the leading causes of irreversible blindness worldwide. In addition to environmental risk factors, such as tobacco use and diet, genetic background has long been established as a major risk factor for the development of AMD. However, our ability to predict disease risk and personalize treatment remains limited by our nascent understanding of the molecular mechanisms underlying AMD pathogenesis. Research into the molecular genetics of AMD over the past two decades has uncovered 52 independent gene variants and 34 independent loci that are implicated in the development of AMD, accounting for over half of the genetic risk. This research has helped delineate at least five major pathways that may be disrupted in the pathogenesis of AMD: the complement system, extracellular matrix remodeling, lipid metabolism, angiogenesis, and oxidative stress response. This review surveys our current understanding of each of these disease mechanisms, in turn, along with their associated pathogenic gene variants. Continued research into the molecular genetics of AMD holds great promise for the development of precision-targeted, personalized therapies that bring us closer to a cure for this debilitating disease.
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Affiliation(s)
- Aumer Shughoury
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Duriye Damla Sevgi
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Thomas A Ciulla
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Clearside Biomedical, Inc., Alpharetta, GA 30005, USA
- Midwest Eye Institute, Indianapolis, IN 46290, USA
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17
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Generation of an iPSC line (SCTCi014-A) and isogenic control line (SCTCi014-A-1) from an age-related macular degeneration patient carrying the variant c.355G>A in the CFI gene. Stem Cell Res 2022; 62:102797. [PMID: 35526386 DOI: 10.1016/j.scr.2022.102797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/29/2022] [Accepted: 04/28/2022] [Indexed: 11/22/2022] Open
Abstract
Age-related macular degeneration (AMD) is a common eye disease among the elderly in the Western world. AMD is a multifactorial disease, with a strong association with genetic variation in the complement system. One of the AMD-associated variants is the c.355G>A (p.Gly119Arg) variant in complement factor I (CFI), a central regulator of complement activation. Here, we report the generation of an iPSC line and its isogenic wildtype control derived from peripheral blood mononuclear cells of a male AMD-affected individual carrying the heterozygous variant c.355G>A (p.Gly119Arg). The line can be utilized to study the effects of this variant in disease-specific cell types.
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18
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de Jong S, Koolen L, Vázquez-Domínguez I, de Breuk A, Albert S, Hoyng CB, Katti S, den Hollander AI, Garanto A. Generation of an iPSC line (SCTCi015-A) and isogenic control line (SCTCi015-A-1) from an age-related macular degeneration patient carrying the variant c.355G>A in the CFI gene. Stem Cell Res 2022; 62:102796. [PMID: 35526389 DOI: 10.1016/j.scr.2022.102796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/29/2022] [Accepted: 04/28/2022] [Indexed: 12/01/2022] Open
Abstract
Age-related macular degeneration (AMD) is a common eye disease among the elderly in the Western world. AMD is a multifactorial disease, with a strong association with genetic variation in the complement system. One of the AMD-associated variants is the c.355G>A (p.Gly119Arg) variant in complement factor I (CFI), a central regulator of complement activation. Here, we report the generation of an iPSC line and its isogenic wildtype control derived from peripheral blood mononuclear cells of a female AMD-affected individual carrying the heterozygous variant c.355G>A (p.Gly119Arg). This line can be utilized to study the effects of this variant in disease-specific cell types.
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Affiliation(s)
- Sarah de Jong
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Louet Koolen
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Irene Vázquez-Domínguez
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Anita de Breuk
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Silvia Albert
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Carel B Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | - Anneke I den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands; Department of Human Genetics, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Alejandro Garanto
- Department of Pediatrics and Department of Human Genetics, Amalia Children's Hospital, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.
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19
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Jones AV, MacGregor S, Han X, Francis J, Harris C, Kavanagh D, Lotery A, Waheed N. Evaluating a Causal Relationship between Complement Factor I Protein Level and Advanced Age-Related Macular Degeneration Using Mendelian Randomization. OPHTHALMOLOGY SCIENCE 2022; 2:100146. [PMID: 35693873 PMCID: PMC9186402 DOI: 10.1016/j.xops.2022.100146] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 01/05/2023]
Abstract
Importance Risk of advanced age-related macular degeneration (AAMD) is associated with rare genetic variants in the gene encoding Complement factor I (CFI), which is associated with lower circulating CFI protein levels, but the nature of the relationship is unclear. Objective Can genetic factors be used to infer whether low circulating CFI is associated with AAMD risk? Design Two-sample inverse variance weighted Mendelian Randomisation (MR) was used to evaluate evidence for a relationship between CFI levels and AAMD risk, comparing CFI levels from genetically predefined subsets in AAMD and control cohorts. Setting Published genetic and proteomic data was combined with data from cohorts of Geographic Atrophy (GA) patients in a series of MR analyses. Participants We derived genetic instruments for systemic CFI level in 3,301 healthy European participants in the INTERVAL study. To evaluate a genetic causal odds ratio (OR) for the effect of CFI levels on AAMD risk, we used results from a genome-wide association study of 12,711 AAMD cases and 14,590 European controls from the International AMD Genomics Consortium (IAMDGC), and CFI levels from patients entered into the research studies SCOPE and SIGHT. Results We identified one common CFI variant rs7439493 which was strongly associated with low CFI level, explaining 4.8% of phenotypic variance. Using rs7439493 our MR analysis estimated that AAMD odds increased per standard deviation (SD) decrease in CFI level; OR 1.47 (95% confidence interval (CI) 1.30-1.65, P=2.1×10-10). We identified one rare variant (rs141853578 encoding p.Gly119Arg) which was genome-wide significantly associated with CFI levels after imputation; based on this, a 1 SD decrease in CFI leads to increased AAMD odds of 1.79 (95% CI 1.46-2.19, P=1.9×10-8). The rare variant rs141853578 explained a further 1.7% of phenotypic variance. To benchmark the effect of low CFI levels on AAMD odds using a CFI-specific proteomic assay, we estimated the effect using CFI levels from 24 rs141853578 positive GA patients; each 1 SD (3.5μg/mL) reduction in CFI was associated with 1.67 fold increased odds of AAMD (95% CI 1.40-2.00, P=1.85×10-8). Conclusion and relevance Excellent concordance in direction and effect size derived from rare and common variant calculations provide good genetic evidence for a potentially causal role of lower CFI level increasing AAMD risk.
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Affiliation(s)
- Amy V. Jones
- Gyroscope Therapeutics Ltd., London, United Kingdom
| | - Stuart MacGregor
- Statistical Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Xikun Han
- Statistical Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- School of Medicine, University of Queensland, Brisbane, Australia
| | | | - Claire Harris
- Gyroscope Therapeutics Ltd., London, United Kingdom
- Clinical & Translational Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David Kavanagh
- Clinical & Translational Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
- National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
| | - Andrew Lotery
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- Southampton Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom
| | - Nadia Waheed
- Gyroscope Therapeutics Ltd., London, United Kingdom
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts
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20
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Fatal Thrombotic Microangiopathy Case following Adeno-Associated Viral SMN Gene Therapy. Blood Adv 2022; 6:4266-4270. [PMID: 35584395 PMCID: PMC9327533 DOI: 10.1182/bloodadvances.2021006419] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 05/09/2022] [Indexed: 12/02/2022] Open
Abstract
This is the first fatal TMA following SMN AAV9 gene therapy in a child carrying a potential predisposing risk factor in the complement factor I gene. A better understanding of the pathophysiology underlying TMA induced by AAV gene therapy is essential to ensure patient safety.
Adeno-associated virus (AAV) gene therapies are highly promising, such as the onasemnogene abeparvovec (Zolgensma) in spinal muscle atrophy (SMA). We report the first case of fatal systemic thrombotic microangiopathy (TMA) following onasemnogene abeparvovec in a 6-month-old child with SMA type 1, carrying a potential genetic predisposition in the complement factor I gene. Other cases of TMA have recently been reported after onasemnogene abeparvovec and after AAV9 minidystrophin therapy in Duchenne muscular dystrophy. The risk-benefit ratio of this therapy must therefore be assessed. Early recognition of TMA and targeted immunotherapy are fundamental to ensure the safety of patients treated with AAV gene therapies.
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21
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Zhang Y, Goodfellow RX, Ghiringhelli Borsa N, Dunlop HC, Presti SA, Meyer NC, Shao D, Roberts SM, Jones MB, Pitcher GR, Taylor AO, Nester CM, Smith RJH. Complement Factor I Variants in Complement-Mediated Renal Diseases. Front Immunol 2022; 13:866330. [PMID: 35619721 PMCID: PMC9127439 DOI: 10.3389/fimmu.2022.866330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/08/2022] [Indexed: 11/26/2022] Open
Abstract
C3 glomerulopathy (C3G) and atypical hemolytic uremic syndrome (aHUS) are two rare diseases caused by dysregulated activity of the alternative pathway of complement secondary to the presence of genetic and/or acquired factors. Complement factor I (FI) is a serine protease that downregulates complement activity in the fluid phase and/or on cell surfaces in conjunction with one of its cofactors, factor H (FH), complement receptor 1 (CR1/CD35), C4 binding protein (C4BP) or membrane cofactor protein (MCP/CD46). Because altered FI activity is causally related to the pathogenesis of C3G and aHUS, we sought to test functional activity of select CFI missense variants in these two patient cohorts. We identified 65 patients (16, C3G; 48, aHUS; 1 with both) with at least one rare variant in CFI (defined as a MAF < 0.1%). Eight C3G and eleven aHUS patients also carried rare variants in either another complement gene, ADAMTS13 or THBD. We performed comprehensive complement analyses including biomarker profiling, pathway activity and autoantibody testing, and developed a novel FI functional assay, which we completed on 40 patients. Seventy-eight percent of rare CFI variants (31/40) were associated with FI protein levels below the 25th percentile; in 22 cases, FI levels were below the lower limit of normal (type 1 variants). Of the remaining nine variants, which associated with normal FI levels, two variants reduced FI activity (type 2 variants). No patients carried currently known autoantibodies (including FH autoantibodies and nephritic factors). We noted that while rare variants in CFI predispose to complement-mediated diseases, phenotypes are strongly contingent on the associated genetic background. As a general rule, in isolation, a rare CFI variant most frequently leads to aHUS, with the co-inheritance of a CD46 loss-of-function variant driving the onset of aHUS to the younger age group. In comparison, co-inheritance of a gain-of-function variant in C3 alters the phenotype to C3G. Defects in CFH (variants or fusion genes) are seen with both C3G and aHUS. This variability underscores the complexity and multifactorial nature of these two complement-mediated renal diseases.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Richard J. H. Smith
- Molecular Otolaryngology and Renal Research Laboratories, University of Iowa, Iowa City, IA, United States
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22
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Java A, Pozzi N, Schroeder MC, Hu Z, Huan T, Seddon JM, Atkinson J. Functional analysis of rare genetic variants in complement factor I in advanced age-related macular degeneration. Hum Mol Genet 2022; 31:3683-3693. [PMID: 35531992 PMCID: PMC9616575 DOI: 10.1093/hmg/ddac103] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/07/2022] [Accepted: 04/28/2022] [Indexed: 11/14/2022] Open
Abstract
Factor I (FI) is a serine protease inhibitor of the complement system. Heterozygous rare genetic variants in complement factor I (CFI) are associated with advanced age-related macular degeneration (AMD). The clinical impact of these variants is unknown since a majority have not been functionally characterized and are classified as 'variants of uncertain significance' (VUS). This study assessed the functional significance of VUS in CFI. Our previous cross-sectional study using a serum-based assay demonstrated that CFI variants in advanced AMD can be categorized into three types. Type 1 variants cause a quantitative deficiency of FI. Type 2 variants demonstrate a qualitative deficiency. However, Type 3 variants consist of VUS that are less dysfunctional than Types 1 and 2 but are not as biologically active as wild type (WT). In this study, we employed site-directed mutagenesis followed by expression of the recombinant variant and a comprehensive set of functional assays to characterize nine Type 3 variants that were identified in 37 individuals. Our studies establish that the expression of the recombinant protein compared with WT is reduced for R202I, Q217H, S221Y and G263V. Further, G362A and N536K, albeit expressed normally, have significantly less cofactor activity. These results led to re-categorization of CFI variants R202I, Q217H, S221Y and G263V as Type 1 variants and to reclassification of N536K and G362A as Type 2. The variants K441R, Q462H and I492L showed no functional defect and remained as Type 3. This study highlights the utility of an in-depth biochemical analysis in defining the pathologic and clinical implications of complement variants underlying AMD.
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Affiliation(s)
- Anuja Java
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Nicola Pozzi
- Department of Biochemistry and Molecular Biology, Edward A. Doisy Research Center, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Molly C Schroeder
- Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zheng Hu
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tianxiao Huan
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | | | - John Atkinson
- To whom correspondence should be addressed at: Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA. Tel: +1 3143628391; Fax: +1 3143621366;
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Vignette-Based Reflections to Inform Genetic Testing Policies in Living Kidney Donors. Genes (Basel) 2022; 13:genes13040592. [PMID: 35456398 PMCID: PMC9025319 DOI: 10.3390/genes13040592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/16/2022] [Accepted: 03/23/2022] [Indexed: 01/01/2023] Open
Abstract
Family history of kidney disease increases risk of end-stage kidney disease (ESKD) in donors. Pre-donation genetic testing is recommended in evaluation guidelines and regulatory policy. Collaborating across several institutions, we describe cases to illustrate the utility as well as practical issues in incorporating genetic testing in transplant protocols. Case 1 is from 2009, before pervasive genetic testing. A healthy 27-year-old Caucasian male had an uneventful donor evaluation for his mother, who had early onset ESKD of unclear cause. He participated in paired-exchange kidney donation, but developed progressive kidney disease and gout over the next 10 years. A uromodulin gene mutation (NM_003361.3(UMOD):c.377 G>A p.C126Y) was detected and kidney biopsy showed tubulointerstitial kidney disease. The patient subsequently required kidney transplantation himself. Case 2 was a 36-year-old African American female who had an uneventful kidney donor evaluation. She underwent gene panel-based testing to rule out ApolipoproteinL1 risk variants, for which was negative. Incidentally, a sickle-cell trait (NM_000518.5(HBB):c.20A>T p.Glu7Val) was noted, and she was declined for kidney donation. This led to significant patient anguish. Case 3 was a 26-year-old Caucasian female who underwent panel-based testing because the potential recipient, her cousin, carried a variant of uncertain significance in the hepatocyte nuclear factor-1-β (HNF1B) gene. While the potential donor did not harbor this variant, she was found to have a likely pathogenic variant in complement factor I (NM_000204.4(CFI):c.1311dup:p.Asp438Argfs*8), precluding kidney donation. Our cases emphasize that while genetic testing can be invaluable in donor evaluation, transplant centers should utilize detailed informed consent, develop care pathways for secondary genetic findings, and share experience to develop best practices around genetic testing in donors.
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Tzoumas N, Kavanagh D, Cordell HJ, Lotery AJ, Patel PJ, Steel DH. Rare complement factor I variants associated with reduced macular thickness and age-related macular degeneration in the UK biobank. Hum Mol Genet 2022; 31:2678-2692. [PMID: 35285476 PMCID: PMC9402241 DOI: 10.1093/hmg/ddac060] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 11/24/2022] Open
Abstract
To evaluate potential diagnostic and therapeutic biomarkers for age-related macular degeneration (AMD), we identified 8433 UK Biobank participants with rare complement Factor I gene (CFI) variants, 579 with optical coherence tomography-derived macular thickness data. We stratified these variants by predicted gene expression and measured their association with retinal pigment epithelium-Bruch’s membrane (RPE-BM) complex and retinal thicknesses at nine macular subfields, as well as AMD risk, using multivariable regression models adjusted for the common complement Factor H gene (CFH) p.Y402H and age-related maculopathy susceptibility protein 2 gene (ARMS2) p.A69S risk genotypes. CFI variants associated with low Factor I levels predicted a thinner mean RPE-BM (95% confidence interval [CI] −1.66 to −0.37 μm, P = 0.002) and retina (95% CI −5.88 to −0.13 μm, P = 0.04) and a higher AMD risk (odds ratio [OR] = 2.26, 95% CI 1.56 to 3.27, P < 0.001). CFI variants associated with normal Factor I levels did not impact mean RPE-BM/retinal thickness (P = 0.28; P = 0.99) or AMD risk (P = 0.97). CFH p.Y402H was associated with a thinner RPE-BM (95% CI −0.31 to −0.18 μm, P < 0.001 heterozygous; 95% CI −0.62 to −0.42 μm, P < 0.001 homozygous) and retina (95% CI −0.73 to −0.12 μm, P = 0.007 heterozygous; 95% CI −1.08 to −0.21 μm, P = 0.004 homozygous). ARMS2 p.A69S did not influence RPE-BM (P = 0.80 heterozygous; P = 0.12 homozygous) or retinal thickness (P = 0.75 heterozygous; P = 0.07 homozygous). p.Y402H and p.A69S exhibited a significant allele–dose response with AMD risk. Thus, CFI rare variants associated with low Factor I levels are robust predictors of reduced macular thickness and AMD. The observed association between macular thickness and CFH p.Y402H, but not ARMS2 p.A69S, highlights the importance of complement dysregulation in early pathogenesis.
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Affiliation(s)
- Nikolaos Tzoumas
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David Kavanagh
- Complement Therapeutics Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
- National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
| | - Heather J Cordell
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Andrew J Lotery
- Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Praveen J Patel
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
| | - David H Steel
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
- Sunderland Eye Infirmary, Sunderland, United Kingdom
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Wong MD, Patel C, McTaggart S, Wainwright CE. Atypical haemolytic uraemic syndrome in a child with cystic fibrosis. J Paediatr Child Health 2022; 58:532-535. [PMID: 34008207 DOI: 10.1111/jpc.15571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/17/2021] [Accepted: 05/09/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew D Wong
- Department of Paediatric Respiratory and Sleep Medicine, Queensland Children's Hospital, Brisbane, Queensland, Australia.,Child Health Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Chirag Patel
- Genetic Health Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Steven McTaggart
- Queensland Child and Adolescent Renal Service, Queensland Children's Hospital, Brisbane, Queensland, Australia.,Children's Health Queensland Clinical Unit, The University of Queensland, Brisbane, Queensland, Australia
| | - Claire E Wainwright
- Department of Paediatric Respiratory and Sleep Medicine, Queensland Children's Hospital, Brisbane, Queensland, Australia.,Child Health Research Centre, The University of Queensland, Brisbane, Queensland, Australia
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26
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de Jong S, de Breuk A, Bakker B, Katti S, Hoyng CB, Nilsson SC, Blom AM, van den Heuvel LP, den Hollander AI, Volokhina EB. Functional Analysis of Variants in Complement Factor I Identified in Age-Related Macular Degeneration and Atypical Hemolytic Uremic Syndrome. Front Immunol 2022; 12:789897. [PMID: 35069568 PMCID: PMC8766660 DOI: 10.3389/fimmu.2021.789897] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 12/13/2021] [Indexed: 11/23/2022] Open
Abstract
Complement factor I (FI) is a central inhibitor of the complement system, and impaired FI function increases complement activation, contributing to diseases such as age-related macular degeneration (AMD) and atypical hemolytic uremic syndrome (aHUS). Genetic variation in complement factor I (CFI) has been identified in both AMD and aHUS, with more than half of these variants leading to reduced FI secretion levels. For many of the variants with normal FI secretion, however, functional implications are not yet known. Here we studied 11 rare missense variants, with FI secretion levels comparable to wildtype, but a predicted damaging effects based on the Combined Annotation Dependent Depletion (CADD) score. Three variants (p.Pro50Ala, p.Arg339Gln, and p.Ser570Thr) were analyzed in plasma and serum samples of carriers affected by AMD. All 11 variants (nine for the first time in this study) were recombinantly expressed and the ability to degrade C3b was studied with the C3b degradation assay. The amount of degradation was determined by measuring the degradation product iC3b with ELISA. Eight of 11 (73%) mutant proteins (p.Pro50Ala, p.Arg339Gln, p.Ile340Thr, p.Gly342Glu, p.Gly349Arg, p.Arg474Gln, p.Gly487Cys, and p.Gly512Ser) showed significantly impaired C3b degradation, and were therefore classified as likely pathogenic. Our data indicate that genetic variants in CFI with a CADD score >20 are likely to affect FI function, and that monitoring iC3b in a degradation assay is a useful tool to establish the pathogenicity of CFI variants in functional studies.
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Affiliation(s)
- Sarah de Jong
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Anita de Breuk
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Bjorn Bakker
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Suresh Katti
- Gemini Therapeutics Inc., Cambridge, MA, United States
| | - Carel B Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Sara C Nilsson
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Anna M Blom
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Lambert P van den Heuvel
- Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Anneke I den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Human Genetics, Radboud University Medical Center, Nijmegen, Netherlands
| | - Elena B Volokhina
- Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
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27
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Acar IE, Willems E, Kersten E, Keizer-Garritsen J, Kragt E, Bakker B, Galesloot TE, Hoyng CB, Fauser S, van Gool AJ, Lechanteur YTE, Koertvely E, Nogoceke E, Gloerich J, de Jonge MI, Lorés-Motta L, den Hollander AI. Semi-Quantitative Multiplex Profiling of the Complement System Identifies Associations of Complement Proteins with Genetic Variants and Metabolites in Age-Related Macular Degeneration. J Pers Med 2021; 11:jpm11121256. [PMID: 34945728 PMCID: PMC8705464 DOI: 10.3390/jpm11121256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/12/2021] [Accepted: 11/19/2021] [Indexed: 12/20/2022] Open
Abstract
Age-related macular degeneration (AMD) is a major cause of vision loss among the elderly in the Western world. The complement system has been identified as one of the main AMD disease pathways. We performed a comprehensive expression analysis of 32 complement proteins in plasma samples of 255 AMD patients and 221 control individuals using mass spectrometry-based semi-quantitative multiplex profiling. We detected significant associations of complement protein levels with age, sex and body-mass index (BMI), and potential associations of C-reactive protein, factor H related-2 (FHR-2) and collectin-11 with AMD. In addition, we confirmed previously described associations and identified new associations of AMD variants with complement levels. New associations include increased C4 levels for rs181705462 at the C2/CFB locus, decreased vitronectin (VTN) levels for rs11080055 at the TMEM97/VTN locus and decreased factor I levels for rs10033900 at the CFI locus. Finally, we detected significant associations between AMD-associated metabolites and complement proteins in plasma. The most significant complement-metabolite associations included increased high density lipoprotein (HDL) subparticle levels with decreased C3, factor H (FH) and VTN levels. The results of our study indicate that demographic factors, genetic variants and circulating metabolites are associated with complement protein components. We suggest that these factors should be considered to design personalized treatment approaches and to increase the success of clinical trials targeting the complement system.
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Affiliation(s)
- I. Erkin Acar
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
| | - Esther Willems
- Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (E.W.); (M.I.d.J.)
- Radboud Center for Infectious Diseases, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.K.-G.); (E.K.); (A.J.v.G.); (J.G.)
| | - Eveline Kersten
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
| | - Jenneke Keizer-Garritsen
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.K.-G.); (E.K.); (A.J.v.G.); (J.G.)
| | - Else Kragt
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.K.-G.); (E.K.); (A.J.v.G.); (J.G.)
| | - Bjorn Bakker
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
| | - Tessel E. Galesloot
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands;
| | - Carel B. Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
| | - Sascha Fauser
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 124 Grenzacherstrasse, 4070 Basel, Switzerland; (S.F.); (E.K.); (E.N.)
| | - Alain J. van Gool
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.K.-G.); (E.K.); (A.J.v.G.); (J.G.)
| | - Yara T. E. Lechanteur
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
| | - Elod Koertvely
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 124 Grenzacherstrasse, 4070 Basel, Switzerland; (S.F.); (E.K.); (E.N.)
| | - Everson Nogoceke
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 124 Grenzacherstrasse, 4070 Basel, Switzerland; (S.F.); (E.K.); (E.N.)
| | - Jolein Gloerich
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.K.-G.); (E.K.); (A.J.v.G.); (J.G.)
| | - Marien I. de Jonge
- Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (E.W.); (M.I.d.J.)
- Radboud Center for Infectious Diseases, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Laura Lorés-Motta
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 124 Grenzacherstrasse, 4070 Basel, Switzerland; (S.F.); (E.K.); (E.N.)
| | - Anneke I. den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (I.E.A.); (E.K.); (B.B.); (C.B.H.); (Y.T.E.L.); (L.L.-M.)
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Correspondence:
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Afanasyeva TAV, Corral-Serrano JC, Garanto A, Roepman R, Cheetham ME, Collin RWJ. A look into retinal organoids: methods, analytical techniques, and applications. Cell Mol Life Sci 2021; 78:6505-6532. [PMID: 34420069 PMCID: PMC8558279 DOI: 10.1007/s00018-021-03917-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/14/2021] [Accepted: 08/09/2021] [Indexed: 12/15/2022]
Abstract
Inherited retinal diseases (IRDs) cause progressive loss of light-sensitive photoreceptors in the eye and can lead to blindness. Gene-based therapies for IRDs have shown remarkable progress in the past decade, but the vast majority of forms remain untreatable. In the era of personalised medicine, induced pluripotent stem cells (iPSCs) emerge as a valuable system for cell replacement and to model IRD because they retain the specific patient genome and can differentiate into any adult cell type. Three-dimensional (3D) iPSCs-derived retina-like tissue called retinal organoid contains all major retina-specific cell types: amacrine, bipolar, horizontal, retinal ganglion cells, Müller glia, as well as rod and cone photoreceptors. Here, we describe the main applications of retinal organoids and provide a comprehensive overview of the state-of-art analysis methods that apply to this model system. Finally, we will discuss the outlook for improvements that would bring the cellular model a step closer to become an established system in research and treatment development of IRDs.
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Affiliation(s)
- Tess A V Afanasyeva
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | | | - Alejandro Garanto
- Department of Pediatrics, Amalia Children's Hospital and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ronald Roepman
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michael E Cheetham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK.
| | - Rob W J Collin
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
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29
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Demirs JT, Yang J, Crowley MA, Twarog M, Delgado O, Qiu Y, Poor S, Rice DS, Dryja TP, Anderson K, Liao SM. Differential and Altered Spatial Distribution of Complement Expression in Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2021; 62:26. [PMID: 34160562 PMCID: PMC8237111 DOI: 10.1167/iovs.62.7.26] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose Dysregulation of the alternative complement pathway is a major pathogenic mechanism in age-related macular degeneration. We investigated whether locally synthesized complement components contribute to AMD by profiling complement expression in postmortem eyes with and without AMD. Methods AMD severity grade 1 to 4 was determined by analysis of postmortem acquired fundus images and hematoxylin and eosin stained histological sections. TaqMan (donor eyes n = 39) and RNAscope/in situ hybridization (n = 10) were performed to detect complement mRNA. Meso scale discovery assay and Western blot (n = 31) were used to measure complement protein levels. Results The levels of complement mRNA and protein expression were approximately 15- to 100-fold (P < 0.0001–0.001) higher in macular retinal pigment epithelium (RPE)/choroid tissue than in neural retina, regardless of AMD grade status. Complement mRNA and protein levels were modestly elevated in vitreous and the macular neural retina in eyes with geographic atrophy (GA), but not in eyes with early or intermediate AMD, compared to normal eyes. Alternative and classical pathway complement mRNAs (C3, CFB, CFH, CFI, C1QA) identified by RNAscope were conspicuous in areas of atrophy; in those areas C3 mRNA was observed in a subset of IBA1+ microglia or macrophages. Conclusions We verified that RPE/choroid contains most ocular complement; thus RPE/choroid rather than the neural retina or vitreous is likely to be the key site for complement inhibition to treat GA or earlier stage of the disease. Outer retinal local production of complement mRNAs along with evidence of increased complement activation is a feature of GA.
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Affiliation(s)
- John T Demirs
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Junzheng Yang
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Maura A Crowley
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Michael Twarog
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Omar Delgado
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Yubin Qiu
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Stephen Poor
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Dennis S Rice
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Thaddeus P Dryja
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Karen Anderson
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
| | - Sha-Mei Liao
- Department of Ophthalmology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States
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30
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de Jong S, Gagliardi G, Garanto A, de Breuk A, Lechanteur YTE, Katti S, van den Heuvel LP, Volokhina EB, den Hollander AI. Implications of genetic variation in the complement system in age-related macular degeneration. Prog Retin Eye Res 2021; 84:100952. [PMID: 33610747 DOI: 10.1016/j.preteyeres.2021.100952] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 12/23/2022]
Abstract
Age-related macular degeneration (AMD) is the main cause of vision loss among the elderly in the Western world. While AMD is a multifactorial disease, the complement system was identified as one of the main pathways contributing to disease risk. The strong link between the complement system and AMD was demonstrated by genetic associations, and by elevated complement activation in local eye tissue and in the systemic circulation of AMD patients. Several complement inhibitors have been and are being explored in clinical trials, but thus far with limited success, leaving the majority of AMD patients without treatment options to date. This indicates that there is still a gap of knowledge regarding the functional implications of the complement system in AMD pathogenesis and how to bring these towards clinical translation. Many different experimental set-ups and disease models have been used to study complement activation in vivo and in vitro, and recently emerging patient-derived induced pluripotent stem cells and genome-editing techniques open new opportunities to study AMD disease mechanisms and test new therapeutic strategies in the future. In this review we provide an extensive overview of methods employed to understand the molecular processes of complement activation in AMD pathogenesis. We discuss the findings, advantages and challenges of each approach and conclude with an outlook on how recent, exciting developments can fill in current knowledge gaps and can aid in the development of effective complement-targeting therapeutic strategies in AMD.
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Affiliation(s)
- Sarah de Jong
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Giuliana Gagliardi
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Alejandro Garanto
- Department of Human Genetics, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Pediatrics, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Amalia Children's Hospital, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Anita de Breuk
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Yara T E Lechanteur
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Suresh Katti
- Gemini Therapeutics Inc., Cambridge, MA, 02139, USA
| | - Lambert P van den Heuvel
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Amalia Children's Hospital, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Laboratory Medicine, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Elena B Volokhina
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Amalia Children's Hospital, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Laboratory Medicine, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Anneke I den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Human Genetics, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands.
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31
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Timmermans SAMEG, Damoiseaux JGMC, Werion A, Reutelingsperger CP, Morelle J, van Paassen P. Functional and Genetic Landscape of Complement Dysregulation Along the Spectrum of Thrombotic Microangiopathy and its Potential Implications on Clinical Outcomes. Kidney Int Rep 2021; 6:1099-1109. [PMID: 33912760 PMCID: PMC8071658 DOI: 10.1016/j.ekir.2021.01.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 01/25/2021] [Indexed: 01/30/2023] Open
Abstract
Introduction The syndromes of thrombotic microangiopathy (TMA) are diverse and represent severe endothelial damage caused by various mechanisms. The complement system plays a major role in a subset of patients with TMA, and its recognition is of clinical importance because it guides choice and duration of treatment. Methods We studied a well-defined cohort of patients with TMA and hypothesized that assessment of serum-induced ex vivo C5b9 formation on the endothelium and screening for rare variants in complement genes can better categorize TMA. Results Massive ex vivo C5b9 formation was found in all patients with primary atypical hemolytic uremic syndrome (n/N = 11/11) and in 59% of patients with TMA and coexisting conditions (n/N = 30/51). Massive ex vivo C5b9 formation was associated with rare genetic variants (45% [n/N = 20/44] vs. 0% [n/N = 0/21] patients with normal ex vivo C5b9 formation; P < 0.001). Massive ex vivo C5b9 formation was associated with favorable renal response to therapeutic complement inhibition in patients with TMA and coexisting conditions (86% [n/N = 12/14] vs. 31% [n/N = 5/16] of untreated patients; P < 0.001), indicating complement-mediated TMA rather than secondary disease. Among treated patients, the odds ratio for 1-year kidney survival was 12.0 (95% confidence interval 1.2-115.4). TMA recurrence was linked to rare genetic variants in all cases. Patients with normal ex vivo C5b9 formation had an acute, nonrelapsing form of TMA. Conclusions Ex vivo C5b9 formation and genetic testing appears to categorize TMAs into different groups because it identifies complement as a driving factor of disease, with potential therapeutic and prognostic implications.
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Affiliation(s)
- Sjoerd A M E G Timmermans
- Department of Nephrology and Clinical Immunology.,Department of Biochemistry, Cardiovascular Research Institute, Maastricht, The Netherlands
| | - Jan G M C Damoiseaux
- Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Alexis Werion
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | | | - Johann Morelle
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.,Institut de Recherche Experimentale et Clinique, UCLouvain, Brussels, Belgium
| | - Pieter van Paassen
- Department of Nephrology and Clinical Immunology.,Department of Biochemistry, Cardiovascular Research Institute, Maastricht, The Netherlands
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