1
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Massri M, Foco L, Würzner R. Comprehensive Update and Revision of Nomenclature on Complement C6 and C7 Variants. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:2597-2612. [PMID: 35867677 DOI: 10.4049/jimmunol.2200045] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
Complement genes encompass a wide array of variants, giving rise to numerous protein isoforms that have often been shown to exhibit clinical significance. Given that these variants have been discovered over a span of 50 y, one challenging consequence is the inconsistency in the terminology used to classify them. This issue is prominently evident in the nomenclature used for complement C6 and C7 variants, for which we observed a great discrepancy between previously published works and variants described in current genome browsers. This report discusses the causes for the discrepancies in C6 and C7 nomenclature and seeks to establish a classification system that would unify existing and future variants. The inconsistency in the methods used to annotate amino acids and the modifications pinpointed in the C6 and C7 primers are some of the factors that contribute greatly to the discrepancy in the nomenclature. Several variants that were classified incorrectly are highlighted in this report, and we showcase first-hand how a unified classification system is important to match previous with current genetic information. Ultimately, we hope that the proposed classification system of nomenclature becomes an incentive for studies on complement variants and their physiological and/or pathological effects.
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Affiliation(s)
- Mariam Massri
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria; and
| | - Luisa Foco
- Institute for Biomedicine (affiliated with the University of Lübeck), Eurac Research, Bolzano, Italy
| | - Reinhard Würzner
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria; and
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2
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Korhonen LS, Lukkarinen M, Kantojärvi K, Räty P, Karlsson H, Paunio T, Peltola V, Karlsson L. Interactions of genetic variants and prenatal stress in relation to the risk for recurrent respiratory infections in children. Sci Rep 2021; 11:7589. [PMID: 33828172 PMCID: PMC8027646 DOI: 10.1038/s41598-021-87211-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 03/17/2021] [Indexed: 12/24/2022] Open
Abstract
Genetic variants may predispose children to recurrent respiratory infections (RRIs) but studies on genotype-environment interaction are rare. We hypothesized that the risk for RRIs is elevated in children with innate immune gene variants, and that prenatal exposure to maternal psychological distress further increases the risk. In a birth cohort, children with RRIs (n = 96) were identified by the age of 24 months and compared with the remaining cohort children (n = 894). The risk for RRIs in children with preselected genetic variants and the interaction between maternal distress during pregnancy and child genotype were assessed with logistic regression. The IL6 minor allele G was associated with elevated risk for RRIs (OR 1.55; 95% CI 1.14-2.12). Overall, there was no interaction between maternal psychological distress and child genotype. Exploratory analyses showed that, the association between the variant type of IL6 and the risk for RRIs was dependent on prenatal exposure to maternal psychological distress in males (OR 1.96; 95% CI 1.04-3.67). Our study didn't find genotype-environment interaction between prenatal maternal distress and child genotype. Exploratory analyses suggest sex differences in gene-environment interaction related to susceptibility to RRIs.
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Affiliation(s)
- Laura S Korhonen
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland. .,Department of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, P.O. Box 52, 20521, Turku, Finland.
| | - Minna Lukkarinen
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland.,Department of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, P.O. Box 52, 20521, Turku, Finland
| | - Katri Kantojärvi
- Genomics and Biobank Unit, Finnish Institute for Health and Welfare, Helsinki, Finland.,Department of Psychiatry and SleepWell Research Program, Faculty of Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Panu Räty
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland
| | - Hasse Karlsson
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland.,Department of Psychiatry, Turku University Hospital and University of Turku, Turku, Finland.,Centre for Population Health Research, University of Turku and Turku University Hospital, Turku, Finland
| | - Tiina Paunio
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland.,Genomics and Biobank Unit, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Ville Peltola
- Department of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, P.O. Box 52, 20521, Turku, Finland
| | - Linnea Karlsson
- Department of Clinical Medicine, FinnBrain Birth Cohort Study, Turku Brain and Mind Center, University of Turku, Turku, Finland.,Centre for Population Health Research, University of Turku and Turku University Hospital, Turku, Finland
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3
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Zhang AQ, Liu YX, Jin JY, Wang CY, Fan LL, Xu DB. Identification of a novel mutation in the C6 gene of a Han Chinese C6SD child with meningococcal disease. Exp Ther Med 2021; 21:510. [PMID: 33791019 DOI: 10.3892/etm.2021.9941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 02/05/2021] [Indexed: 11/06/2022] Open
Abstract
Deficiency of the sixth complement component (C6D) is a genetic disease associated with increased susceptibility to Neisseria meningitides infection. Individuals with C6D usually present with recurrent meningococcal disease (MD). According to the patients' C6 levels, C6D is divided into complete genetic deficiency of C6 and subtotal deficiency of C6 (C6SD). The present study reported on a Han Chinese pediatric patient with MD, in whom further investigation revealed a C6SD genetic lesion. A heterozygote nonsense mutation (c.1062C>G/p.Y354*) in the C6 gene was identified by Sanger sequencing. The mutation alters the tyrosine codon at position 354 to a termination codon and results in a truncated protein. In conclusion, the genetic lesion of a pediatric patient with C6SD who was diagnosed due to having MD was investigated and a novel pathogenic mutation in the C6 gene was identified. The study confirmed the clinical diagnosis for this patient with C6SD and also expanded the spectrum of C6 mutations.
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Affiliation(s)
- Ai-Qian Zhang
- Department of Obstetrics and Gynecology, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410011, P.R. China
| | - Yu-Xing Liu
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, P.R. China
| | - Jie-Yuan Jin
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, P.R. China
| | - Chen-Yu Wang
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, P.R. China
| | - Liang-Liang Fan
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, P.R. China.,Hunan Key Laboratory of Animals for Human Disease, School of Life Sciences, Central South University, Changsha, Hunan 410013, P.R. China
| | - Da-Bao Xu
- Department of Obstetrics and Gynecology, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410011, P.R. China
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4
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Li PH, Wong WW, Leung EN, Lau CS, Au E. Novel pathogenic mutations identified in the first Chinese pedigree of complete C6 deficiency. Clin Transl Immunology 2020; 9:e1148. [PMID: 32670577 PMCID: PMC7343556 DOI: 10.1002/cti2.1148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 01/25/2023] Open
Abstract
Objectives Complete C6 deficiency (C6Q0) is a rare primary immunodeficiency leading to increased susceptibility to recurrent Neisseria infections. Patients with C6Q0 have mostly been reported in individuals of African ancestry previously, but never in Chinese. We identify the first Chinese patients with C6Q0 through family screening of an index case presenting with recurrent Neisseria meningitis with septicaemia and performed extensive clinical, serological and genetic investigations. Methods Two variants in C6 were identified by next‐generation sequencing and confirmed by Sanger sequencing in an index case of C6Q0. Immunological investigations, complement haemolytic assays (CH50/AH50), C6 gene sequencing and quantification of serum C6 levels were performed for all available members of his nonconsanguineous family. Results Three C6Q0 patients were identified with near‐absent C6 levels, absent CH50/AH50 activity and compound heterozygous for two nonsense mutations in the C6 gene: NM_000065.4:c.1786C>T (p.Arg596Ter) and NM_000065.4:c.1816C>T (p.Arg606Ter). Neither mutations have been reported to be pathogenic previously. Two other family members who were heterozygous for either p.Arg596Ter or and p.Arg606Ter had intermediate C6 levels but preserved CH50/AH50 activity. These two loss‐of‐function mutations showed a strong genotype–phenotype correlation in C6 levels. Conclusions We report on two compound heterozygous mutations in C6, p.Arg596Ter and p.Arg606Ter inherited in three patients of the first recorded Chinese pedigree of C6Q0. Neither mutations had been reported to be pathogenic previously. We demonstrate that heterozygous family members with subtotal C6 levels had preserved complement haemolytic function and demonstrate a threshold effect of C6 protein level.
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Affiliation(s)
- Philip H Li
- Division of Rheumatology & Clinical Immunology Department of Medicine Queen Mary Hospital The University of Hong Kong Hong Kong
| | - William Wy Wong
- Division of Clinical Immunology Department of Pathology Queen Mary Hospital Hong Kong
| | - Evelyn Ny Leung
- Division of Clinical Immunology Department of Pathology Queen Mary Hospital Hong Kong
| | - Chak-Sing Lau
- Division of Rheumatology & Clinical Immunology Department of Medicine Queen Mary Hospital The University of Hong Kong Hong Kong
| | - Elaine Au
- Division of Clinical Immunology Department of Pathology Queen Mary Hospital Hong Kong
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5
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van den Broek B, van Els CACM, Kuipers B, van Aerde K, Henriet SS, de Groot R, de Jonge MI, Langereis JD, van der Flier M. Multi-component meningococcal serogroup B (MenB)-4C vaccine induces effective opsonophagocytic killing in children with a complement deficiency. Clin Exp Immunol 2019; 198:381-389. [PMID: 31487400 PMCID: PMC6857189 DOI: 10.1111/cei.13368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2019] [Indexed: 01/09/2023] Open
Abstract
Vaccination against meningococcal serogroup B is recommended for patients with a complement deficiency; however, although immunogenicity in this patient group has been shown, efficacy has not yet been established. In this study, we collected serum from children with a complement deficiency in the alternative pathway or in late terminal pathway before and after vaccination with multi‐component meningococcal serogroup B (MenB)‐4C. MenB‐4C is a multi‐component, protein‐based vaccine against MenB consisting of factor H‐binding protein, Neisserial heparin‐binding protein, Neisserial adhesion A and outer membrane vesicles containing Porin A. We assessed the vaccine immunogenicity and vaccine‐mediated protection by a whole cell enzyme‐linked immunosorbent assay with Neisseria meningitidis serogroup B strains H44/76, 5/99 and NZ98/254, which shows that vaccination induced antibody titers against meningococcus. We show that the classical serum bactericidal activity assay with exogenous serum indicates the presence of vaccine‐induced antibodies and capacity to activate complement‐mediated pathogen lysis. However, in children with a late terminal pathway deficiency, no complement‐mediated pathogen lysis was observed when autologous serum was applied in the serum bactericidal activity assay, demonstrating a lack of serum bactericidal activity in children with complement deficiencies. However, MenB‐4C vaccination still induced effective complement‐dependent opsonophagocytic killing against N. meningitidis serogroup B in reconstituted whole blood with autologous serum from children with an alternative pathway or late terminal pathway deficiency. These findings support the recommendation to vaccinate all complement‐deficient children against MenB.
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Affiliation(s)
- B van den Broek
- Pediatric Infectious Diseases and Immunology, Amalia Children's Hospital, Nijmegen, the Netherlands.,Expertise Center for Immunodeficiency and Autoinflammation (REIA), Radboudumc, Nijmegen, the Netherlands.,Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - C A C M van Els
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - B Kuipers
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - K van Aerde
- Pediatric Infectious Diseases and Immunology, Amalia Children's Hospital, Nijmegen, the Netherlands.,Expertise Center for Immunodeficiency and Autoinflammation (REIA), Radboudumc, Nijmegen, the Netherlands.,Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - S S Henriet
- Pediatric Infectious Diseases and Immunology, Amalia Children's Hospital, Nijmegen, the Netherlands.,Expertise Center for Immunodeficiency and Autoinflammation (REIA), Radboudumc, Nijmegen, the Netherlands.,Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - R de Groot
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - M I de Jonge
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - J D Langereis
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
| | - M van der Flier
- Pediatric Infectious Diseases and Immunology, Amalia Children's Hospital, Nijmegen, the Netherlands.,Expertise Center for Immunodeficiency and Autoinflammation (REIA), Radboudumc, Nijmegen, the Netherlands.,Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, the Netherlands.,Radboud Center for Infectious Diseases, Radboudumc, Nijmegen, the Netherlands
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6
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Chamberlain JL, Huda S, Whittam DH, Matiello M, Morgan BP, Jacob A. Role of complement and potential of complement inhibitors in myasthenia gravis and neuromyelitis optica spectrum disorders: a brief review. J Neurol 2019; 268:1643-1664. [PMID: 31482201 DOI: 10.1007/s00415-019-09498-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/02/2019] [Accepted: 08/05/2019] [Indexed: 02/08/2023]
Abstract
The complement system is a powerful member of the innate immune system. It is highly adept at protecting against pathogens, but exists in a delicate balance between its protective functions and overactivity, which can result in autoimmune disease. A cascade of complement proteins that requires sequential activation, and numerous complement regulators, exists to regulate a proportionate response to pathogens. In spite of these mechanisms there is significant evidence for involvement of the complement system in driving the pathogenesis of variety of diseases including neuromyelitis optica spectrum disorders (NMOSD) and myasthenia gravis (MG). As an amplification cascade, there are an abundance of molecular targets that could be utilized for therapeutic intervention. Clinical trials assessing complement pathway inhibition in both these conditions have recently been completed and include the first randomized placebo-controlled trial in NMOSD showing positive results. This review aims to review and update the reader on the complement system and the evolution of complement-based therapeutics in these two disorders.
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Affiliation(s)
| | - Saif Huda
- Department of Neurology, The Walton Centre, Lower Lane, Liverpool, L9 7LJ, UK
| | - Daniel H Whittam
- Department of Neurology, The Walton Centre, Lower Lane, Liverpool, L9 7LJ, UK
| | - Marcelo Matiello
- Department of Neurology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA
| | - B Paul Morgan
- School of Medicine, Henry Wellcome Building for Biomedical Research, University Hospital of Wales, Heath Park, Cardiff, CF14 4XN, UK
| | - Anu Jacob
- Department of Neurology, The Walton Centre, Lower Lane, Liverpool, L9 7LJ, UK.,University of Liverpool, Liverpool, UK
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7
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El Sissy C, Rosain J, Vieira-Martins P, Bordereau P, Gruber A, Devriese M, de Pontual L, Taha MK, Fieschi C, Picard C, Frémeaux-Bacchi V. Clinical and Genetic Spectrum of a Large Cohort With Total and Sub-total Complement Deficiencies. Front Immunol 2019; 10:1936. [PMID: 31440263 PMCID: PMC6694794 DOI: 10.3389/fimmu.2019.01936] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/30/2019] [Indexed: 01/11/2023] Open
Abstract
The complement system is crucial for defense against pathogens and the removal of dying cells or immune complexes. Thus, clinical indications for possible complete complement deficiencies include, among others, recurrent mild or serious bacterial infections as well as autoimmune diseases (AID). The diagnostic approach includes functional activity measurements of the classical (CH50) and alternative pathway (AP50) and the determination of the C3 and C4 levels, followed by the quantitative analysis of individual components or regulators. When biochemical analysis reveals the causal abnormality of the complement deficiency (CD), molecular mechanisms remains frequently undetermined. Here, using direct sequencing analysis of the coding region we report the pathogenic variants spectrum that underlie the total or subtotal complement deficiency in 212 patients. We identified 107 different hemizygous, homozygous, or compound heterozygous pathogenic variants in 14 complement genes [C1Qβ (n = 1), C1r (n = 3), C1s (n = 2), C2 (n = 12), C3 (n = 5), C5 (n = 12), C6 (n = 9), C7 (n = 17), C8 β (n = 7), C9 (n = 3), CFH (n = 7), CFI (n = 18), CFP (n = 10), CFD (n = 2)]. Molecular analysis identified 17 recurrent pathogenic variants in 6 genes (C2, CFH, C5, C6, C7, and C8). More than half of the pathogenic variants identified in unrelated patients were also found in healthy controls from the same geographic area. Our study confirms the strong association of meningococcal infections with terminal pathway deficiency and highlights the risk of pneumococcal and auto-immune diseases in the classical and alternative pathways. Results from this large genetic investigation provide evidence of a restricted number of molecular mechanisms leading to complement deficiency and describe the clinical potential adverse events of anti-complement therapy.
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Affiliation(s)
- Carine El Sissy
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Jérémie Rosain
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Paula Vieira-Martins
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Pauline Bordereau
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Aurélia Gruber
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Magali Devriese
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France
| | - Loïc de Pontual
- Pediatrics Department, Jean Verdier Hospital, Assistance Publique des Hôpitaux de Paris, Paris 13 University, Bondy, France
| | - Muhamed-Kheir Taha
- Invasive Bacterial Infection and National Reference Center for Meningococci, Pasteur Institut, Paris, France
| | - Claire Fieschi
- Department of Clinical Immunology, Hôpital Saint-Louis, Assistance Publique - Hôpitaux de Paris (AP-HP), Paris, France.,Inserm U1126, Centre Hayem, Hôpital Saint-Louis, Paris, France
| | - Capucine Picard
- Paris University, INSERM UMR1163, Imagine Institute, Paris, France.,Study Center for Primary Immunodeficiencies (AP-HP), Hôpital Necker-Enfants maladies Hospital, Paris, France
| | - Véronique Frémeaux-Bacchi
- Assistance Publique - Hôpitaux de Paris (AP-HP), Laboratoire d'Immunologie, Hôpital Européen Georges-Pompidou, Paris, France.,Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, USPC, Université Paris Descartes, Complement and Diseases Team, Paris, France
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8
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Uptake of Sialic Acid by Nontypeable Haemophilus influenzae Increases Complement Resistance through Decreasing IgM-Dependent Complement Activation. Infect Immun 2019; 87:IAI.00077-19. [PMID: 30936154 DOI: 10.1128/iai.00077-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 03/21/2019] [Indexed: 01/15/2023] Open
Abstract
Although nontypeable Haemophilus influenzae (NTHi) is a human-specific nasopharyngeal commensal bacterium, it also causes upper respiratory tract infections in children and lower respiratory tract infections in the elderly, resulting in frequent antibiotic use. The transition from symbiotic colonizing bacterium to opportunistic pathogen is not completely understood. Incorporation of sialic acids into lipooligosaccharides is thought to play an important role in bacterial virulence. It has been known for more than 25 years that sialic acids increase resistance to complement-mediated killing; however, the mechanism of action has not been elucidated thus far. Here, we provide evidence that growth of NTHi in the presence of sialic acids Neu5Ac and Neu5Gc decreases complement-mediated killing through abrogating the classical pathway of complement activation by preventing mainly IgM antibody binding to the bacterial surface. Therefore, strategies that interfere with uptake or incorporation of sialic acids into the lipooligosaccharide, such as novel antibiotics and vaccines, might be worth exploring to prevent or treat NTHi infections.
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9
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Liao JH, Li CC, Wu SH, Fan JW, Gu HT, Wang ZW. Gene Variations of Sixth Complement Component Affecting Tacrolimus Metabolism in Patients with Liver Transplantation for Hepatocellular Carcinoma. Chin Med J (Engl) 2017; 130:1670-1676. [PMID: 28685716 PMCID: PMC5520553 DOI: 10.4103/0366-6999.209886] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Orthotopic liver transplantation (OLT) improves the prognosis of patients with hepatocellular carcinoma (HCC). Moreover, the complement system is a powerful immune effector that can affect liver function and process of liver cirrhosis. However, studies correlating the complement system with tacrolimus metabolism after OLT are scarce. In this study, the role of single nucleotide polymorphisms (SNPs) associated with the sixth complement component (C6) in tacrolimus metabolism was investigated during the early stages of liver transplantation. METHODS The study enrolled 135 adult patients treated with OLT for HCC between August 2011 and October 2013. Ten SNPs in C6 gene and rs776746 in cytochrome P450 3A5 (CYP3A5) gene were investigated. The tacrolimus levels were monitored daily during 4 weeks after transplantation. RESULTS Both donor and recipient CYP3A5 rs776746 allele A were correlated with decreased concentration/dose (C/D) ratios. Recipient C6 rs9200 allele G and donor C6 rs10052999 homozygotes were correlated with lower C/D ratios. Recipient CYP3A5 rs776746 allele A (yielded median tacrolimus C/D ratios of 225.90 at week 1 and 123.61 at week 2), C6 rs9200 allele G (exhibited median tacrolimus C/D ratios of 211.31 at week 1, 110.23 at week 2, and 99.88 at week 3), and donor CYP3A5 rs776746 allele A (exhibited median C/D ratios of 210.82 at week 1, 111.06 at week 2, 77.49 at week 3, and 85.60 at week 4) and C6 rs10052999 homozygote (exhibited median C/D ratios of 167.59 at week 2, 157.99 at week 3, and 155.36 at week 4) were associated with rapid tacrolimus metabolism. With increasing number of these alleles, patients were found to have lower tacrolimus C/D ratios at various time points during the 4 weeks after transplantation. In multiple linear regression analysis, recipient C6 rs9200 group (AA vs. GG/GA) was found to be related to tacrolimus metabolism at weeks 1, 2, and 3 (P = 0.005, P = 0.045, and P = 0.033, respectively), whereas donor C6 rs10052999 group (CC/TT vs. TC) was demonstrated to be correlated with tacrolimus metabolism only at week 4 (P = 0.001). CONCLUSIONS Recipient C6 gene rs9200 polymorphism and donor C6 gene rs10052999 polymorphism are new genetic loci that affect tacrolimus metabolism in patients with HCC after OLT.
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Affiliation(s)
- Jian-Hua Liao
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Chang-Can Li
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Shao-Han Wu
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Jun-Wei Fan
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Hai-Tao Gu
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Zhao-Wen Wang
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
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10
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A versatile assay to determine bacterial and host factors contributing to opsonophagocytotic killing in hirudin-anticoagulated whole blood. Sci Rep 2017; 7:42137. [PMID: 28176849 PMCID: PMC5296863 DOI: 10.1038/srep42137] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 01/03/2017] [Indexed: 12/13/2022] Open
Abstract
Most bacteria entering the bloodstream will be eliminated through complement activation on the bacterial surface and opsonophagocytosis. However, when these protective innate immune systems do not work optimally, or when bacteria are equipped with immune evasion mechanisms that prevent killing, this can lead to serious infections such as bacteremia and meningitis, which is associated with high morbidity and mortality. In order to study the complement evasion mechanisms of bacteria and the capacity of human blood to opsonize and kill bacteria, we developed a versatile whole blood killing assay wherein both phagocyte function and complement activity can easily be monitored and modulated. In this assay we use a selective thrombin inhibitor hirudin to fully preserve complement activity of whole blood. This assay allows controlled analysis of the requirements for active complement by replacing or heat-inactivating plasma, phagocyte function and bacterial immune evasion mechanisms that contribute to survival in human blood.
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11
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Wang Z, Liao J, Wu S, Li C, Fan J, Peng Z. Recipient C6 rs9200 genotype is associated with hepatocellular carcinoma recurrence after orthotopic liver transplantation in a Han Chinese population. Cancer Gene Ther 2016; 23:157-61. [PMID: 27173880 DOI: 10.1038/cgt.2016.7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/23/2016] [Accepted: 02/23/2016] [Indexed: 12/22/2022]
Abstract
Hepatocellular carcinoma (HCC) recurrence is one of the leading causes of death after orthotopic liver transplantation (OLT). The sixth complement component (C6) is a late-acting complement protein that participates in the assembly of the membrane attack complex, which has an indispensable role in innate and acquired immune responses, as well as cancer immune surveillance. However, studies assessing the association between C6 and HCC recurrence after OLT are scarce. This study aimed to evaluate the association of donor and recipient C6 single-nucleotide polymorphisms with the risk for HCC recurrence after OLT. A total of 71 adult patients who underwent primary LT for HCC were enrolled. HCC recurrence was observed in 26 (36.6%) patients. Ten single-nucleotide polymorphisms were genotyped and analyzed in both donor and recipient groups. Patients with the rs9200 heterozygous GA variant presented significantly higher HCC recurrence rates (54.17 vs 27.66%, P=0.028), and lower cumulative tumor-free survival and overall survival (P=0.006 and P=0.013, respectively) compared with those harboring the GG/AA genotype, in multivariate logistic regression and Cox regression analyses. The rs9200 heterozygous GA variant in C6 persisted as a statistically independent prognostic factor (P<0.05) for predicting HCC recurrence after OLT. In conclusion, recipient C6 rs9200 polymorphism is associated with HCC recurrence after OLT, and improves the predictive value of clinical models.
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Affiliation(s)
- Z Wang
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - J Liao
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - S Wu
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - C Li
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - J Fan
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Z Peng
- Department of General Surgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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