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Mikucki A, Kahler CM. Microevolution and Its Impact on Hypervirulence, Antimicrobial Resistance, and Vaccine Escape in Neisseria meningitidis. Microorganisms 2023; 11:3005. [PMID: 38138149 PMCID: PMC10745880 DOI: 10.3390/microorganisms11123005] [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: 11/06/2023] [Revised: 12/07/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023] Open
Abstract
Neisseria meningitidis is commensal of the human pharynx and occasionally invades the host, causing the life-threatening illness invasive meningococcal disease. The meningococcus is a highly diverse and adaptable organism thanks to natural competence, a propensity for recombination, and a highly repetitive genome. These mechanisms together result in a high level of antigenic variation to invade diverse human hosts and evade their innate and adaptive immune responses. This review explores the ways in which this diversity contributes to the evolutionary history and population structure of the meningococcus, with a particular focus on microevolution. It examines studies on meningococcal microevolution in the context of within-host evolution and persistent carriage; microevolution in the context of meningococcal outbreaks and epidemics; and the potential of microevolution to contribute to antimicrobial resistance and vaccine escape. A persistent theme is the idea that the process of microevolution contributes to the development of new hyperinvasive meningococcal variants. As such, microevolution in this species has significant potential to drive future public health threats in the form of hypervirulent, antibiotic-resistant, vaccine-escape variants. The implications of this on current vaccination strategies are explored.
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Affiliation(s)
- August Mikucki
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA 6009, Australia;
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Perth, WA 6009, Australia
| | - Charlene M. Kahler
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA 6009, Australia;
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Perth, WA 6009, Australia
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Zografaki I, Detsis M, Del Amo M, Iantomasi R, Maia A, Montuori EA, Mendez C. Invasive Meningococcal Disease epidemiology and vaccination strategies in four Southern European countries: a review of the available data. Expert Rev Vaccines 2023. [PMID: 37316234 DOI: 10.1080/14760584.2023.2225596] [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: 11/16/2022] [Accepted: 06/12/2023] [Indexed: 06/16/2023]
Abstract
INTRODUCTION Invasive meningococcal disease (IMD) is a major health concern which can be prevented through vaccination. Conjugate vaccines against serogroups A, C, W and Y and two protein-based vaccines against serogroup B are currently available in the European Union. AREAS COVERED We present epidemiologic data for Italy, Portugal, Greece and Spain using publicly available reports from national reference laboratories and national or regional immunization programs (1999-2019), aiming to confirm risk groups, and describe time trends in overall incidence and serogroup distribution, as well as impact of immunization. Analysis of circulating MenB isolates in terms of the surface factor H binding protein (fHbp) using PubMLST is discussed as fHbp represents an important MenB vaccine antigen. Predictions of potential reactivity of the two available MenB vaccines (MenB-fHbp and 4CMenB) with circulating MenB isolates are also provided as assessed using the recently developed MenDeVAR tool. EXPERT OPINION Understanding dynamics of IMD and continued genomic surveillance are essential for evaluating vaccine effectiveness, but also prompting proactive immunization programs to prevent future outbreaks. Importantly, the successful design of further effective meningococcal vaccines to fight IMD relies on considering the unpredictable epidemiology of the disease and combining lessons learnt from capsule polysaccharide vaccines and protein-based vaccines.
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Affiliation(s)
| | | | | | | | - Ana Maia
- Vaccines Department, Pfizer Portugal, Lisbon, Portugal
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Rivacoba MC, Villena R, Hormazabal JC, Benadof D, Payá E, Valdivieso F, Canals A, Arteta-Acosta C, Santolaya ME. Hypervirulent Strains of Neisseria meningitidis and Clinical Manifestations in Children With Invasive Meningococcal Disease. Pediatr Infect Dis J 2023; Publish Ahead of Print:00006454-990000000-00470. [PMID: 37267065 DOI: 10.1097/inf.0000000000003965] [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] [Indexed: 06/04/2023]
Abstract
BACKGROUND Hypervirulent clonal complex (cc) have been associated with higher incidence and case fatality rate of invasive meningococcal disease (IMD). The aim of this study was to describe the clinical manifestations of the hypervirulent cc of meningococcus in children. METHODS Retrospective study in patients hospitalized by IMD microbiologically confirmed at three children's tertiary health care centers in Santiago, Chile, between 2010 and 2018. Demographic, clinical information and determination of the cc and factor H binding protein (fHbp) alleles were performed. RESULTS In total 93 cases were evaluated, sequence typing was available for 91 cases, and 87 (95.6%) had a cc assigned; 63.7% were MenW and 31.8% MenB. The median age was 9 months, 67% were male and 18.7% had any comorbidity. A 26.4% presented neurological deficit, 25.3% petechiae and 20% diarrhea. Sixty-seven percent were admitted to the pediatric intensive care unit (PICU) and the case fatality rate was 9.9%. Regarding cc and fHbp alleles, ST11, ST41/44 and allele 22 were the most frequently identified, with 63.7%, 19.8% and 72.5%, respectively. We found statistically significant differences between the cc and presence of petechiae, diagnosis of meningococcemia plus meningitis, admission and days in PICU and advanced support. Allele 22 for fHbp was associated with the absence of petechiae, low suspicion of IMD, less diagnosis of meningitis+meningococcemia, PICU admission, advanced support and adrenal insufficiency. CONCLUSION Epidemiological and microbiological surveillance of IMD should integrate clinical and laboratory components, including molecular and genetic characterization, to enrich the dynamic understanding of the clinical evolution of IMD.
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Affiliation(s)
- María Carolina Rivacoba
- From the Infectious Diseases Unit, Hospital de niños Dr. Exequiel González Cortés, Santiago, Chile
| | - Rodolfo Villena
- From the Infectious Diseases Unit, Hospital de niños Dr. Exequiel González Cortés, Santiago, Chile
- Department of Pediatrics, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | | | - Dona Benadof
- Department of Pediatrics, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Microbiology Laboratory, Hospital de niños Dr Roberto Del Río, Santiago, Chile
| | - Ernesto Payá
- From the Infectious Diseases Unit, Hospital de niños Dr. Exequiel González Cortés, Santiago, Chile
- Department of Pediatrics, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Francisca Valdivieso
- Infectious Diseases Unit, Hospital de niños Dr Luis Calvo Mackenna, Santiago, Chile
| | - Andrea Canals
- Academic Direction, Clínica Santa Maria, Santiago, Chile
- Biostatistics Program, School of Public Health, Universidad de Chile, Santiago, Chile
| | - Cindy Arteta-Acosta
- Department of Pediatrics, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Infectious Diseases Unit, Hospital de niños Dr Luis Calvo Mackenna, Santiago, Chile
| | - María Elena Santolaya
- Department of Pediatrics, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Infectious Diseases Unit, Hospital de niños Dr Luis Calvo Mackenna, Santiago, Chile
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Mikucki A, McCluskey NR, Kahler CM. The Host-Pathogen Interactions and Epicellular Lifestyle of Neisseria meningitidis. Front Cell Infect Microbiol 2022; 12:862935. [PMID: 35531336 PMCID: PMC9072670 DOI: 10.3389/fcimb.2022.862935] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/28/2022] [Indexed: 01/17/2023] Open
Abstract
Neisseria meningitidis is a gram-negative diplococcus and a transient commensal of the human nasopharynx. It shares and competes for this niche with a number of other Neisseria species including N. lactamica, N. cinerea and N. mucosa. Unlike these other members of the genus, N. meningitidis may become invasive, crossing the epithelium of the nasopharynx and entering the bloodstream, where it rapidly proliferates causing a syndrome known as Invasive Meningococcal Disease (IMD). IMD progresses rapidly to cause septic shock and meningitis and is often fatal despite aggressive antibiotic therapy. While many of the ways in which meningococci survive in the host environment have been well studied, recent insights into the interactions between N. meningitidis and the epithelial, serum, and endothelial environments have expanded our understanding of how IMD develops. This review seeks to incorporate recent work into the established model of pathogenesis. In particular, we focus on the competition that N. meningitidis faces in the nasopharynx from other Neisseria species, and how the genetic diversity of the meningococcus contributes to the wide range of inflammatory and pathogenic potentials observed among different lineages.
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Affiliation(s)
- August Mikucki
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
| | - Nicolie R. McCluskey
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
- College of Science, Health, Engineering and Education, Telethon Kids Institute, Murdoch University, Perth, WA, Australia
| | - Charlene M. Kahler
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
- *Correspondence: Charlene M. Kahler,
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de Lemos APS, Sacchi CT, Gonçalves CR, Camargo CH, Andrade AL. Genomic surveillance of Neisseria meningitidis serogroup B invasive strains: Diversity of vaccine antigen types, Brazil, 2016-2018. PLoS One 2020; 15:e0243375. [PMID: 33347452 PMCID: PMC7751880 DOI: 10.1371/journal.pone.0243375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 11/19/2020] [Indexed: 11/19/2022] Open
Abstract
Background Neisseria meningitidis serogroup B remains a prominent cause of invasive meningococcal disease (IMD) in Brazil. Because two novel protein-based vaccines against serogroup B are available, the main purpose of this study was to provide data on the diversity and distribution of meningococcal vaccine antigen types circulating in Brazil. Methodology Genetic lineages, vaccine antigen types, and allele types of antimicrobial-associated resistance genes based on whole-genome sequencing of a collection of 145 Neisseria meningitidis serogroup B invasive strains recovered in Brazil from 2016 to 2018 were collected. Results A total of 11 clonal complexes (ccs) were identified among the 145 isolates, four of which were predominant, namely, cc461, cc35, cc32, and cc213, accounting for 72.0% of isolates. The most prevalent fHbp peptides were 24 (subfamily A/variant 2), 47 (subfamily A/variant 3), 1 (subfamily B/variant 1) and 45 (subfamily A/variant 3), which were predominantly associated with cc35, cc461, cc32, and cc213, respectively. The NadA peptide was detected in only 26.2% of the isolates. The most frequent NadA peptide 1 was found almost exclusively in cc32. We found seven NHBA peptides that accounted for 74.5% of isolates, and the newly described peptide 1390 was the most prevalent peptide exclusively associated with cc461. Mutated penA alleles were detected in 56.5% of the isolates, whereas no rpoB and gyrA mutant alleles were found. Conclusion During the study period, changes in the clonal structure of circulating strains were observed, without a predominance of a single hyperinvasive lineage, indicating that an epidemiologic shift has occurred that led to a diversity of vaccine antigen types in recent years in Brazil.
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Affiliation(s)
| | | | | | | | - Ana Lúcia Andrade
- Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Brazil
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Meningococcal Deduced Vaccine Antigen Reactivity (MenDeVAR) Index: a Rapid and Accessible Tool That Exploits Genomic Data in Public Health and Clinical Microbiology Applications. J Clin Microbiol 2020; 59:JCM.02161-20. [PMID: 33055180 PMCID: PMC7771438 DOI: 10.1128/jcm.02161-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/09/2020] [Indexed: 12/24/2022] Open
Abstract
As microbial genomics makes increasingly important contributions to clinical and public health microbiology, the interpretation of whole-genome sequence data by nonspecialists becomes essential. In the absence of capsule-based vaccines, two protein-based vaccines have been used for the prevention of invasive serogroup B meningococcal disease (IMD) since their licensure in 2013 and 2014. These vaccines have different components and different levels of coverage of meningococcal variants. Hence, decisions regarding which vaccine to use in managing serogroup B IMD outbreaks require information about the index case isolate, including (i) the presence of particular vaccine antigen variants, (ii) the expression of vaccine antigens, and (iii) the likely susceptibility of its antigen variants to antibody-dependent bactericidal killing. As microbial genomics makes increasingly important contributions to clinical and public health microbiology, the interpretation of whole-genome sequence data by nonspecialists becomes essential. In the absence of capsule-based vaccines, two protein-based vaccines have been used for the prevention of invasive serogroup B meningococcal disease (IMD) since their licensure in 2013 and 2014. These vaccines have different components and different levels of coverage of meningococcal variants. Hence, decisions regarding which vaccine to use in managing serogroup B IMD outbreaks require information about the index case isolate, including (i) the presence of particular vaccine antigen variants, (ii) the expression of vaccine antigens, and (iii) the likely susceptibility of its antigen variants to antibody-dependent bactericidal killing. To obtain this information requires a multitude of laboratory assays, impractical in real-time clinical settings, where the information is most urgently needed. To facilitate assessment for public health and clinical purposes, we synthesized genomic and experimental data from published sources to develop and implement the Meningococcal Deduced Vaccine Antigen Reactivity (MenDeVAR) Index, which is publicly available on PubMLST (https://pubmlst.org). Using whole-genome sequences or individual gene sequences obtained from IMD isolates or clinical specimens, the MenDeVAR Index provides rapid evidence-based information on the presence and possible immunological cross-reactivity of different meningococcal vaccine antigen variants. The MenDeVAR Index enables practitioners who are not genomics specialists to assess the likely reactivity of vaccines for individual cases, outbreak management, or the assessment of public health vaccine programs. The MenDeVAR Index has been developed in consultation with, but independently of, both the 4CMenB (Bexsero; GSK) and rLP2086 (Trumenba; Pfizer, Inc.) vaccine manufacturers.
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Binepal G, Mabanglo MF, Goodreid JD, Leung E, Barghash MM, Wong KS, Lin F, Cossette M, Bansagi J, Song B, Balasco Serrão VH, Pai EF, Batey RA, Gray-Owen SD, Houry WA. Development of Antibiotics That Dysregulate the Neisserial ClpP Protease. ACS Infect Dis 2020; 6:3224-3236. [PMID: 33237740 DOI: 10.1021/acsinfecdis.0c00599] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Evolving antimicrobial resistance has motivated the search for novel targets and alternative therapies. Caseinolytic protease (ClpP) has emerged as an enticing new target since its function is conserved and essential for bacterial fitness, and because its inhibition or dysregulation leads to bacterial cell death. ClpP protease function controls global protein homeostasis and is, therefore, crucial for the maintenance of the bacterial proteome during growth and infection. Previously, acyldepsipeptides (ADEPs) were discovered to dysregulate ClpP, leading to bactericidal activity against both actively growing and dormant Gram-positive pathogens. Unfortunately, these compounds had very low efficacy against Gram-negative bacteria. Hence, we sought to develop non-ADEP ClpP-targeting compounds with activity against Gram-negative species and called these activators of self-compartmentalizing proteases (ACPs). These ACPs bind and dysregulate ClpP in a manner similar to ADEPs, effectively digesting bacteria from the inside out. Here, we performed further ACP derivatization and testing to improve the efficacy and breadth of coverage of selected ACPs against Gram-negative bacteria. We observed that a diverse collection of Neisseria meningitidis and Neisseria gonorrhoeae clinical isolates were exquisitely sensitive to these ACP analogues. Furthermore, based on the ACP-ClpP cocrystal structure solved here, we demonstrate that ACPs could be designed to be species specific. This validates the feasibility of drug-based targeting of ClpP in Gram-negative bacteria.
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Affiliation(s)
- Gursonika Binepal
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Mark F. Mabanglo
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Jordan D. Goodreid
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Elisa Leung
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Marim M. Barghash
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Keith S. Wong
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Funing Lin
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Michele Cossette
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Jazmin Bansagi
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Boxi Song
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Vitor Hugo Balasco Serrão
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Emil F. Pai
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
- Ontario Cancer Institute/Princess Margaret Hospital, Toronto, Ontario M5G 1L7, Canada
| | - Robert A. Batey
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Scott D. Gray-Owen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Walid A. Houry
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5G 1M1, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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Kremer PH, Lees JA, Ferwerda B, Bijlsma MW, MacAlasdair N, van der Ende A, Brouwer MC, Bentley SD, van de Beek D. Diversification in immunogenicity genes caused by selective pressures in invasive meningococci. Microb Genom 2020; 6:mgen000422. [PMID: 32776867 PMCID: PMC7643973 DOI: 10.1099/mgen.0.000422] [Citation(s) in RCA: 2] [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: 02/13/2020] [Accepted: 07/26/2020] [Indexed: 11/21/2022] Open
Abstract
We studied population genomics of 486 Neisseria meningitidis isolates causing meningitis in the Netherlands during the period 1979-2003 and 2006-2013 using whole-genome sequencing to evaluate the impact of a hyperendemic period of serogroup B invasive disease. The majority of serogroup B isolates belonged to ST-41/44 (41 %) and ST-32 complex (16 %). Comparing the time periods, before and after the decline of serogroup B invasive disease, there was a decrease of ST-41/44 complex sequences (P=0.002). We observed the expansion of a sub-lineage within ST-41/44 complex sequences being associated with isolation from the 1979-2003 time period (P=0.014). Isolates belonging to this sub-lineage expansion within ST-41/44 complex were marked by four antigen allele variants. Presence of these allele variants was associated with isolation from the 1979-2003 time period after correction for multiple testing (Wald test, P=0.0043 for FetA 1-5; P=0.0035 for FHbp 14; P=0.012 for PorA 7-2.4 and P=0.0031 for NHBA two peptide allele). These sequences were associated with 4CMenB vaccine coverage (Fisher's exact test, P<0.001). Outside of the sub-lineage expansion, isolates with markedly lower levels of predicted vaccine coverage clustered in phylogenetic groups showing a trend towards isolation in the 2006-2013 time period (P=0.08). In conclusion, we show the emergence and decline of a sub-lineage expansion within ST-41/44 complex isolates concurrent with a hyperendemic period in meningococcal meningitis. The expansion was marked by specific antigen peptide allele combinations. We observed preliminary evidence for decreasing 4CMenB vaccine coverage in the post-hyperendemic period.
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Affiliation(s)
- Philip H.C. Kremer
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscienc, Amsterdam, The Netherlands
| | - John A. Lees
- Parasites and Microbes, Wellcome Sanger Institute, Hixton, Cambridge, UK
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Bart Ferwerda
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscienc, Amsterdam, The Netherlands
| | - Merijn W. Bijlsma
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscienc, Amsterdam, The Netherlands
| | - Neil MacAlasdair
- Parasites and Microbes, Wellcome Sanger Institute, Hixton, Cambridge, UK
| | - Arie van der Ende
- Amsterdam UMC, Department of Medical Microbiology and the Netherlands Reference Laboratory for Bacterial Meningitis, Amsterdam, The Netherlands
| | - Matthijs C. Brouwer
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscienc, Amsterdam, The Netherlands
| | - Stephen D. Bentley
- Parasites and Microbes, Wellcome Sanger Institute, Hixton, Cambridge, UK
| | - Diederik van de Beek
- Amsterdam UMC, University of Amsterdam, Department of Neurology, Amsterdam Neuroscienc, Amsterdam, The Netherlands
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Principato S, Pizza M, Rappuoli R. Meningococcal factor H binding protein as immune evasion factor and vaccine antigen. FEBS Lett 2020; 594:2657-2669. [PMID: 32298465 DOI: 10.1002/1873-3468.13793] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/25/2020] [Accepted: 03/30/2020] [Indexed: 01/15/2023]
Abstract
Factor H binding protein (fHbp) is a key virulence factor of Neisseria meningitidis and a main component of the two licensed vaccines against serogroup B meningococcus (Bexsero and Trumenba). fHbp is a surface-exposed lipoprotein that enables the bacterium to survive in human blood by binding the human complement regulator factor H (fH). When used as vaccine, the protein induces antibodies with potent bactericidal activity. While the fHbp gene is present in the majority of N. meningitidis serogroup B isolates, the expression level varies up to 15 times between different strains and more than 700 different sequence variants have been described. Antigenically, the protein has been divided into three variants or two subfamilies. The 3D structure of fHbp alone, in combination with fH or in complex with bactericidal antibodies, has been key to understanding the molecular details of the protein. In this article, we will review the biochemical and immunological properties of fHbp, and its key role in meningococcal pathogenesis, complement regulation, and immune evasion.
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Bettinger JA, Liberator P, Halperin SA, Vaudry W, Sadarangani M, Hao L, Lambert N, Jansen KU, Anderson AS, Tsang R. Estimated susceptibility of Canadian meningococcal B isolates to a meningococcal serogroup B vaccine (MenB-FHbp). Vaccine 2020; 38:2026-2033. [PMID: 31983586 DOI: 10.1016/j.vaccine.2019.12.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Invasive meningococcal disease caused by Neisseria meningitidis serogroup B (MenB) remains a health risk in Canada and globally. Two MenB vaccines are now approved for use. An understanding of the genotype of Canadian strains and the potential strain coverage conferred by the MenB-FHbp vaccine is needed to inform immunization policies. METHODS Serogroup B Neisseria meningitidis strains responsible for meningococcal disease in Canada from 2006 to 2012 were collected as part of the Canadian Immunization Monitoring Program Active surveillance network. Genotypic analysis was done on MenB isolates from 2006 to 2012 with determination of fHbp surface expression for a subset of isolates: those occurring from 2010 to 2012. RESULTS Two clonal complexes (cc269 and cc41/44) were observed in 68.8% of the 276 isolates. A total of 50 different fHbp peptides were identified among isolates from 2006 to 2012. Surface expression of fHbp was detected on 95% of MenB isolates from 2010 to 2012 and 91% of isolates expressed fHbp at levels that are predicted to be susceptible to the bactericidal immune response elicited by the MenB-FHbp vaccine. Some regional differences were observed, particularly in isolates from British Columbia and Quebec. CONCLUSION The majority of MenB isolates responsible for meningococcal disease in Canada expressed fHbp at levels predicted to be sufficient for complement mediated bactericidal activity in the presence of MenB-FHbp induced serum antibodies.
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Affiliation(s)
- Julie A Bettinger
- Vaccine Evaluation Center, BC Children's Hospital and the University of British Columbia, Vancouver V5Z4H4, Canada.
| | - Paul Liberator
- Vaccine Research and Development, Pfizer, Inc., Pearl River, NY 10965, USA
| | - Scott A Halperin
- Canadian Center for Vaccinology, IWK Health Centre and Dalhousie University, Halifax B3K6R8, Canada
| | - Wendy Vaudry
- Stollery Children's Hospital and University of Alberta, Edmonton T6G1C9, Canada
| | - Manish Sadarangani
- Vaccine Evaluation Center, BC Children's Hospital and the University of British Columbia, Vancouver V5Z4H4, Canada
| | - Li Hao
- Vaccine Research and Development, Pfizer, Inc., Pearl River, NY 10965, USA
| | - Nathaniel Lambert
- Vaccine Research and Development, Pfizer, Inc., Pearl River, NY 10965, USA; Juno Therapeutics, A Celgene Company, Seattle, WA 98102, USA
| | - Kathrin U Jansen
- Vaccine Research and Development, Pfizer, Inc., Pearl River, NY 10965, USA
| | | | - Raymond Tsang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg R3E3R2, Canada
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da Silva RAG, Karlyshev AV, Oldfield NJ, Wooldridge KG, Bayliss CD, Ryan A, Griffin R. Variant Signal Peptides of Vaccine Antigen, FHbp, Impair Processing Affecting Surface Localization and Antibody-Mediated Killing in Most Meningococcal Isolates. Front Microbiol 2019; 10:2847. [PMID: 31921030 PMCID: PMC6930937 DOI: 10.3389/fmicb.2019.02847] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/25/2019] [Indexed: 11/24/2022] Open
Abstract
Meningococcal lipoprotein, Factor H binding protein (FHbp), is the sole antigen of the Trumenba vaccine (Pfizer) and one of four antigens of the Bexsero vaccine (GSK) targeting Neisseria meningitidis serogroup B isolates. Lipidation of FHbp is assumed to occur for all isolates. We show in the majority of a collection of United Kingdom isolates (1742/1895) non-synonymous single nucleotide polymorphisms (SNPs) in the signal peptide (SP) of FHbp. A single SNP, common to all, alters a polar amino acid that abolishes processing: lipidation and SP cleavage. Whilst some of the FHbp precursor is retained in the cytoplasm due to reduced binding to SecA, remarkably some is translocated and further surface-localized by Slam. Thus we show Slam is not lipoprotein-specific. In a panel of isolates tested, the overall reduced surface localization of the precursor FHbp, compared to isolates with an intact SP, corresponded with decreased susceptibility to antibody-mediated killing. Our findings shed new light on the canonical pathway for lipoprotein processing and translocation of important relevance for lipoprotein-based vaccines in development and in particular for Trumenba.
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Affiliation(s)
- Ronni A G da Silva
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Andrey V Karlyshev
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston upon Thames, United Kingdom
| | - Neil J Oldfield
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Karl G Wooldridge
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Christopher D Bayliss
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Ali Ryan
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston upon Thames, United Kingdom
| | - Ruth Griffin
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
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Rodrigues CMC, Chan H, Vipond C, Jolley K, Harrison OB, Wheeler J, Whiting G, Feavers IM, Maiden MCJ. Typing complex meningococcal vaccines to understand diversity and population structure of key vaccine antigens. Wellcome Open Res 2019; 3:151. [PMID: 30687793 DOI: 10.12688/wellcomeopenres.14859.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2018] [Indexed: 11/20/2022] Open
Abstract
Background: Protein-conjugate capsular polysaccharide vaccines can potentially control invasive meningococcal disease (IMD) caused by five (A, C, W, X, Y) of the six IMD-associated serogroups. Concerns raised by immunological similarity of the serogroup B capsule to human neural cell carbohydrates, meant that 'serogroup B substitute' vaccines target more variable subcapsular protein antigens. A successful approach using outer membrane vesicles (OMVs) as major vaccine components had limited strain coverage. In 4CMenB (Bexsero ®), recombinant proteins have been added to ameliorate this problem. Methods: Scalable, portable, genomic techniques were used to investigate the Bexsero ® OMV protein diversity in meningococcal populations. Shotgun proteomics identified 461 proteins in the OMV, defining a complex proteome. Amino acid sequences for the 24 proteins most likely to be involved in cross-protective immune responses were catalogued within the PubMLST.org/neisseria database using a novel OMV peptide Typing (OMVT) scheme. Results: Among these proteins there was variation in the extent of diversity and association with meningococcal lineages, identified as clonal complexes (ccs), ranging from the most conserved peptides (FbpA, NEISp0578, and putative periplasmic protein, NEISp1063) to the most diverse (TbpA, NEISp1690). There were 1752 unique OMVTs identified amongst 2492/3506 isolates examined by whole-genome sequencing (WGS). These OMVTs were grouped into clusters (sharing ≥18 identical OMVT peptides), with 45.3% of isolates assigned to one of 27 OMVT clusters. OMVTs and OMVT clusters were strongly associated with cc, genogroup, and Bexsero ® antigen variants, demonstrating that combinations of OMV proteins exist in discrete, non-overlapping combinations associated with genogroup and Bexsero ® Antigen Sequence Type. This highly structured population of IMD-associated meningococci is consistent with strain structure models invoking host immune and/or metabolic selection. Conclusions: The OMVT scheme facilitates region-specific WGS investigation of meningococcal diversity and is an open-access, portable tool with applications for vaccine development, especially in the choice of antigen combinations, assessment and implementation.
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Affiliation(s)
| | - Hannah Chan
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Caroline Vipond
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Keith Jolley
- Department of Zoology, University of Oxford, Oxford, OX1 3SY, UK
| | - Odile B Harrison
- Department of Zoology, University of Oxford, Oxford, OX1 3SY, UK
| | - Jun Wheeler
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Gail Whiting
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Ian M Feavers
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
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13
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Rodrigues CMC, Chan H, Vipond C, Jolley K, Harrison OB, Wheeler J, Whiting G, Feavers IM, Maiden MCJ. Typing complex meningococcal vaccines to understand diversity and population structure of key vaccine antigens. Wellcome Open Res 2019; 3:151. [PMID: 30687793 PMCID: PMC6338130 DOI: 10.12688/wellcomeopenres.14859.2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2019] [Indexed: 01/09/2023] Open
Abstract
Background: Protein-conjugate capsular polysaccharide vaccines can potentially control invasive meningococcal disease (IMD) caused by five (A, C, W, X, Y) of the six IMD-associated serogroups. Concerns raised by immunological similarity of the serogroup B capsule to human neural cell carbohydrates, meant that ‘serogroup B substitute’ vaccines target more variable subcapsular protein antigens. A successful approach using outer membrane vesicles (OMVs) as major vaccine components had limited strain coverage. In 4CMenB (Bexsero
®), recombinant proteins have been added to ameliorate this problem. Methods: Scalable, portable, genomic techniques were used to investigate the Bexsero
® OMV protein diversity in meningococcal populations. Shotgun proteomics identified 461 proteins in the OMV, defining a complex proteome. Amino acid sequences for the 24 proteins most likely to be involved in cross-protective immune responses were catalogued within the
PubMLST.org/neisseria database using a novel OMV peptide Typing (OMVT) scheme. Results: Among these proteins there was variation in the extent of diversity and association with meningococcal lineages, identified as clonal complexes (ccs), ranging from the most conserved peptides (FbpA, NEISp0578, and putative periplasmic protein, NEISp1063) to the most diverse (TbpA, NEISp1690). There were 1752 unique OMVTs identified amongst 2492/3506 isolates examined by whole-genome sequencing (WGS). These OMVTs were grouped into clusters (sharing ≥18 identical OMVT peptides), with 45.3% of isolates assigned to one of 27 OMVT clusters. OMVTs and OMVT clusters were strongly associated with cc, genogroup, and Bexsero
® antigen variants, demonstrating that combinations of OMV proteins exist in discrete, non-overlapping combinations associated with genogroup and Bexsero
® Antigen Sequence Type. This highly structured population of IMD-associated meningococci is consistent with strain structure models invoking host immune and/or metabolic selection. Conclusions:The OMVT scheme facilitates region-specific WGS investigation of meningococcal diversity and is an open-access, portable tool with applications for vaccine development, especially in the choice of antigen combinations, assessment and implementation.
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Affiliation(s)
| | - Hannah Chan
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Caroline Vipond
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Keith Jolley
- Department of Zoology, University of Oxford, Oxford, OX1 3SY, UK
| | - Odile B Harrison
- Department of Zoology, University of Oxford, Oxford, OX1 3SY, UK
| | - Jun Wheeler
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Gail Whiting
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
| | - Ian M Feavers
- Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK
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Bogaerts B, Winand R, Fu Q, Van Braekel J, Ceyssens PJ, Mattheus W, Bertrand S, De Keersmaecker SCJ, Roosens NHC, Vanneste K. Validation of a Bioinformatics Workflow for Routine Analysis of Whole-Genome Sequencing Data and Related Challenges for Pathogen Typing in a European National Reference Center: Neisseria meningitidis as a Proof-of-Concept. Front Microbiol 2019; 10:362. [PMID: 30894839 PMCID: PMC6414443 DOI: 10.3389/fmicb.2019.00362] [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: 10/11/2018] [Accepted: 02/12/2019] [Indexed: 12/22/2022] Open
Abstract
Despite being a well-established research method, the use of whole-genome sequencing (WGS) for routine molecular typing and pathogen characterization remains a substantial challenge due to the required bioinformatics resources and/or expertise. Moreover, many national reference laboratories and centers, as well as other laboratories working under a quality system, require extensive validation to demonstrate that employed methods are "fit-for-purpose" and provide high-quality results. A harmonized framework with guidelines for the validation of WGS workflows does currently, however, not exist yet, despite several recent case studies highlighting the urgent need thereof. We present a validation strategy focusing specifically on the exhaustive characterization of the bioinformatics analysis of a WGS workflow designed to replace conventionally employed molecular typing methods for microbial isolates in a representative small-scale laboratory, using the pathogen Neisseria meningitidis as a proof-of-concept. We adapted several classically employed performance metrics specifically toward three different bioinformatics assays: resistance gene characterization (based on the ARG-ANNOT, ResFinder, CARD, and NDARO databases), several commonly employed typing schemas (including, among others, core genome multilocus sequence typing), and serogroup determination. We analyzed a core validation dataset of 67 well-characterized samples typed by means of classical genotypic and/or phenotypic methods that were sequenced in-house, allowing to evaluate repeatability, reproducibility, accuracy, precision, sensitivity, and specificity of the different bioinformatics assays. We also analyzed an extended validation dataset composed of publicly available WGS data for 64 samples by comparing results of the different bioinformatics assays against results obtained from commonly used bioinformatics tools. We demonstrate high performance, with values for all performance metrics >87%, >97%, and >90% for the resistance gene characterization, sequence typing, and serogroup determination assays, respectively, for both validation datasets. Our WGS workflow has been made publicly available as a "push-button" pipeline for Illumina data at https://galaxy.sciensano.be to showcase its implementation for non-profit and/or academic usage. Our validation strategy can be adapted to other WGS workflows for other pathogens of interest and demonstrates the added value and feasibility of employing WGS with the aim of being integrated into routine use in an applied public health setting.
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Affiliation(s)
- Bert Bogaerts
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
| | - Raf Winand
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
| | - Qiang Fu
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
| | - Julien Van Braekel
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
| | | | | | | | | | - Nancy H C Roosens
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
| | - Kevin Vanneste
- Transversal Activities in Applied Genomics, Sciensano, Brussels, Belgium
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Rodrigues CMC, Lucidarme J, Borrow R, Smith A, Cameron JC, Moxon ER, Maiden MCJ. Genomic Surveillance of 4CMenB Vaccine Antigenic Variants among Disease-Causing Neisseria meningitidis Isolates, United Kingdom, 2010-2016. Emerg Infect Dis 2019; 24:673-682. [PMID: 29553330 PMCID: PMC5875271 DOI: 10.3201/eid2404.171480] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In September 2015, 4CMenB meningococcal vaccine was introduced into the United Kingdom infant immunization program without phase 3 trial information. Understanding the effect of this program requires enhanced surveillance of invasive meningococcal disease (IMD) Neisseria meningitidis isolates and comparison with prevaccination isolates. Bexsero Antigen Sequence Types (BASTs) were used to analyze whole-genome sequences of 3,073 prevaccine IMD N. meningitidis isolates obtained during 2010−2016. Isolates exhibited 803 BASTs among 31 clonal complexes. Frequencies of antigen peptide variants were factor H binding protein 1, 13.4%; Neisserial heparin-binding antigen 2, 13.8%; Neisseria adhesin A 8, 0.8%; and Porin A-VR2:P1.4,10.9%. In 2015−16, serogroup B isolates showed the highest proportion (35.7%) of exact matches to >1 Bexsero components. Serogroup W isolates showed the highest proportion (93.9%) of putatively cross-reactive variants of Bexsero antigens. Results highlighted the likely role of cross-reactive antigens. BAST surveillance of meningococcal whole-genome sequence data is rapid, scalable, and portable and enables international comparisons of isolates.
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16
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Maiden MCJ. The Impact of Nucleotide Sequence Analysis on Meningococcal Vaccine Development and Assessment. Front Immunol 2019; 9:3151. [PMID: 30697213 PMCID: PMC6340965 DOI: 10.3389/fimmu.2018.03151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/20/2018] [Indexed: 12/21/2022] Open
Abstract
Since it became available as a routine tool in biology, the determination and analysis of nucleotide sequences has been applied to the design of vaccines and the investigation of their effectiveness. As vaccination is primarily concerned with the interaction of biological molecules with the immune system, the utility of sequence data is not immediately obvious and, indeed, nucleotide sequence data are most effective when used to complement more conventional immunological approaches. Here, the impact of sequencing on the field of vaccinology will be illustrated with reference to the development and implementation of vaccines against Neisseria meningitidis (the meningococcus) over the 30-year period from the late-1980s to the late-2010s. Nucleotide sequence-based studies have been important in the fight against this aggressive pathogen largely because of its high genetic and antigenic diversity, properties that were only fully appreciated because of sequence-based studies. Five aspects will be considered, the use of sequence data to: (i) discover vaccine antigens; (ii) assess the diversity and distribution of vaccine antigens; (iii) determine the evolutionary and population biology of the organism and their implications for immunization; and (iv) develop molecular approaches to investigate pre- and post-vaccine pathogen populations to assess vaccine impact. One of the great advantages of nucleotide sequence data has been its scalability, which has meant that increasingly large data sets have been available, which has proved invaluable in the investigation of an organism as diverse and enigmatic as the meningococcus.
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Kesanopoulos K, Bratcher HB, Hong E, Xirogianni A, Papandreou A, Taha MK, Maiden MCJ, Tzanakaki G. Characterization of meningococcal carriage isolates from Greece by whole genome sequencing: Implications for 4CMenB vaccine implementation. PLoS One 2018; 13:e0209919. [PMID: 30592763 PMCID: PMC6310245 DOI: 10.1371/journal.pone.0209919] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 12/13/2018] [Indexed: 12/21/2022] Open
Abstract
Herd protection, resulting from the interruption of transmission and asymptomatic carriage, is an important element of the effectiveness of vaccines against the meningococcus. Whilst this has been well established for conjugate polysaccharide vaccines directed against the meningococcal capsule, two uncertainties surround the potential herd protection provided by the novel protein-based vaccines that are used in place of serogroup B (MenB) polysaccharide vaccines (i) the strain coverage of such vaccines against carried meningococci, which are highly diverse; and (ii) the generation of a protective immune response in the mucosa. These considerations are essential for realistic estimates of cost-effectiveness of new MenB vaccines. Here the first of these questions is addressed by the whole genome sequence (WGS) analysis of meningococci isolated from healthy military recruits and university students in Greece. The study included a total of 71 MenB isolates obtained from 1420 oropharyngeal single swab samples collected from military recruits and university students on voluntary basis, aged 18-26 years. In addition to WGS analysis to identify genetic lineage and vaccine antigen genes, including the Bexsero Antigen Sequence Type (BAST), the isolates were examined with the serological Meningococcal antigen Typing System (MATS) assay. Comparison of these data demonstrated that the carried meningococcal population was highly diverse with 38% of the carriage isolates showed expression of antigens matching those included in the 4CMenB vaccine. Our data may suggest a limited potential herd immunity to be expected and be driven by an impact on a subset of carriage isolates.
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Affiliation(s)
- Konstantinos Kesanopoulos
- National Meningitis Reference Laboratory (NMRL), Dept of Public Health, National School of Public Health, Athens, Greece
| | - Holly B. Bratcher
- Department of Zoology, Peter Medawar Building, University of Oxford, Oxford, United Kingdom
| | - Eva Hong
- Institute Pasteur, Invasive Bacterial Infections Unit, Paris, France
| | - Athanasia Xirogianni
- National Meningitis Reference Laboratory (NMRL), Dept of Public Health, National School of Public Health, Athens, Greece
| | - Anastasia Papandreou
- National Meningitis Reference Laboratory (NMRL), Dept of Public Health, National School of Public Health, Athens, Greece
| | | | - Martin C. J. Maiden
- Department of Zoology, Peter Medawar Building, University of Oxford, Oxford, United Kingdom
| | - Georgina Tzanakaki
- National Meningitis Reference Laboratory (NMRL), Dept of Public Health, National School of Public Health, Athens, Greece
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Invasive meningococcal disease in Shanghai, China from 1950 to 2016: implications for serogroup B vaccine implementation. Sci Rep 2018; 8:12334. [PMID: 30120257 PMCID: PMC6098053 DOI: 10.1038/s41598-018-30048-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 07/23/2018] [Indexed: 11/24/2022] Open
Abstract
Serogroup B invasive meningococcal disease (IMD) is increasing in China, but little is known about the causative meningococci. Here, IMD and carriage isolates in Shanghai characterised and the applicability of different vaccines assessed. Seven IMD epidemic periods have been observed in Shanghai since 1950, with 460 isolates collected including 169 from IMD and 291 from carriage. Analyses were divided according to the period of meningococcal polysaccharide vaccine (MPV) introduction: (i) pre-MPV-A, 1965–1980; (ii) post-MPV-A, 1981–2008; and (iii) post-MPV-A + C, 2009–2016. Over this period, IMD incidence decreased from 55.4/100,000 to 0.71 then to 0.02, corresponding to successive changes in meningococcal type from serogroup A ST-5 complex (MenA:cc5) to MenC:cc4821, and finally MenB:cc4821. MenB IMD became predominant (63.2%) in the post-MPV-A + C period, and 50% of cases were caused by cc4821, with the highest incidence in infants (0.45/100,000) and a case-fatality rate of 9.5%. IMD was positively correlated with population carriage rates. Using the Bexsero Antigen Sequence Type (BAST) system, fewer than 25% of MenB isolates in the post-MPV-A + C period contained exact or predicted cross reactive matches to the vaccines Bexsero, Trumenba, or an outer membrane vesicle (OMV)-based vaccine, NonaMen. A unique IMD epidemiology was seen in China, changing periodically from epidemic to hyperepidemic and low-level endemic disease. At the time of writing, MenB IMD dominated IMD in Shanghai, with isolates potentially beyond coverage with licenced OMV- and protein-based MenB vaccines.
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Andreae CA, Sessions RB, Virji M, Hill DJ. Bioinformatic analysis of meningococcal Msf and Opc to inform vaccine antigen design. PLoS One 2018; 13:e0193940. [PMID: 29547646 PMCID: PMC5856348 DOI: 10.1371/journal.pone.0193940] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/21/2018] [Indexed: 11/19/2022] Open
Abstract
Neisseria meningitidis is an antigenically and genetically variable Gram-negative bacterium and a causative agent of meningococcal meningitis and septicaemia. Meningococci encode many outer membrane proteins, including Opa, Opc, Msf, fHbp and NadA, identified as being involved in colonisation of the host and evasion of the immune response. Although vaccines are available for the prevention of some types of meningococcal disease, none currently offer universal protection. We have used sequences within the Neisseria PubMLST database to determine the variability of msf and opc in 6,500 isolates. In-silico analysis revealed that although opc is highly conserved, it is not present in all isolates, with most isolates in clonal complex ST-11 lacking a functional opc. In comparison, msf is found in all meningococcal isolates, and displays diversity in the N-terminal domain. We identified 20 distinct Msf sequence variants (Msf SV), associated with differences in number of residues within the putative Vn binding motifs. Moreover, we showed distinct correlations with certain Msf SVs and isolates associated with either hyperinvasive lineages or those clonal complexes associated with a carriage state. We have demonstrated differences in Vn binding between three Msf SVs and generated a cross reactive Msf polyclonal antibody. Our study has highlighted the importance of using large datasets to inform vaccine development and provide further information on the antigenic diversity exhibited by N. meningitidis.
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Affiliation(s)
- Clio A. Andreae
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | | | - Mumtaz Virji
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Darryl. J. Hill
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- * E-mail:
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Abstract
There is an urgent need to develop vaccines against pathogenic bacteria. However, this is often hindered by antigenic diversity and difficulties encountered manufacturing membrane proteins. Here we show how to use structure-based design to develop chimeric antigens (ChAs) for subunit vaccines. ChAs are generated against serogroup B Neisseria meningitidis (MenB), the predominant cause of meningococcal disease in wealthy countries. MenB ChAs exploit factor H binding protein (fHbp) as a molecular scaffold to display the immunogenic VR2 epitope from the integral membrane protein PorA. Structural analyses demonstrate fHbp is correctly folded and the PorA VR2 epitope adopts an immunogenic conformation. In mice, immunisation with ChAs generates fHbp and PorA antibodies that recognise the antigens expressed by clinical MenB isolates; these antibody responses correlate with protection against meningococcal disease. Application of ChAs is therefore a potentially powerful approach to develop multivalent subunit vaccines, which can be tailored to circumvent pathogen diversity. Factor H binding protein (fHbp) and PorA are components of experimental serogroup B N. meningitidis vaccines. Here the authors graft the VR2 loop of PorA onto an fHBp-based scaffold to demonstrate proof-of-principle of a chimeric antigen strategy and vaccination against meningococcal disease.
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Neisseria cinerea Expresses a Functional Factor H Binding Protein Which Is Recognized by Immune Responses Elicited by Meningococcal Vaccines. Infect Immun 2017; 85:IAI.00305-17. [PMID: 28739825 PMCID: PMC5607398 DOI: 10.1128/iai.00305-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 07/07/2017] [Indexed: 12/12/2022] Open
Abstract
Neisseria meningitidis is a major cause of bacterial meningitis and sepsis worldwide. Capsular polysaccharide vaccines are available against meningococcal serogroups A, C, W, and Y. More recently two protein-based vaccines, Bexsero and Trumenba, against meningococcal serogroup B strains have been licensed; both vaccines contain meningococcal factor H binding protein (fHbp). fHbp is a surface-exposed lipoprotein that binds the negative complement regulator complement factor H (CFH), thereby inhibiting the alternative pathway of complement activation. Recent analysis of available genomes has indicated that some commensal Neisseria species also contain genes that potentially encode fHbp, although the functions of these genes and how immunization with fHbp-containing vaccines could affect the commensal flora have yet to be established. Here, we show that the commensal species Neisseria cinerea expresses functional fHbp on its surface and that it is responsible for recruitment of CFH by the bacterium. N. cinerea fHbp binds CFH with affinity similar to that of meningococcal fHbp and promotes survival of N. cinerea in human serum. We examined the potential impact of fHbp-containing vaccines on N. cinerea We found that immunization with Bexsero elicits serum bactericidal activity against N. cinerea, which is primarily directed against fHbp. The shared function of fHbp in N. cinerea and N. meningitidis and cross-reactive responses elicited by Bexsero suggest that the introduction of fHbp-containing vaccines has the potential to affect carriage of N. cinerea and other commensal species.
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Patel S, Mathivanan N, Goyal A. Bacterial adhesins, the pathogenic weapons to trick host defense arsenal. Biomed Pharmacother 2017; 93:763-771. [DOI: 10.1016/j.biopha.2017.06.102] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 06/23/2017] [Accepted: 06/29/2017] [Indexed: 12/18/2022] Open
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Fantappiè L, Irene C, De Santis M, Armini A, Gagliardi A, Tomasi M, Parri M, Cafardi V, Bonomi S, Ganfini L, Zerbini F, Zanella I, Carnemolla C, Bini L, Grandi A, Grandi G. Some Gram-negative Lipoproteins Keep Their Surface Topology When Transplanted from One Species to Another and Deliver Foreign Polypeptides to the Bacterial Surface. Mol Cell Proteomics 2017; 16:1348-1364. [PMID: 28483926 PMCID: PMC5500766 DOI: 10.1074/mcp.m116.065094] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 05/05/2017] [Indexed: 11/29/2022] Open
Abstract
In Gram-negative bacteria, outer membrane-associated lipoproteins can either face the periplasm or protrude out of the bacterial surface. The mechanisms involved in lipoprotein transport through the outer membrane are not fully elucidated. Some lipoproteins reach the surface by using species-specific transport machinery. By contrast, a still poorly characterized group of lipoproteins appears to always cross the outer membrane, even when transplanted from one organism to another. To investigate such lipoproteins, we tested the expression and compartmentalization in E. coli of three surface-exposed lipoproteins, two from Neisseria meningitidis (Nm-fHbp and NHBA) and one from Aggregatibacter actinomycetemcomitans (Aa-fHbp). We found that all three lipoproteins were lipidated and compartmentalized in the E. coli outer membrane and in outer membrane vesicles. Furthermore, fluorescent antibody cell sorting analysis, proteolytic surface shaving, and confocal microscopy revealed that all three proteins were also exposed on the surface of the outer membrane. Removal or substitution of the first four amino acids following the lipidated cysteine residue and extensive deletions of the C-terminal regions in Nm-fHbp did not prevent the protein from reaching the surface of the outer membrane. Heterologous polypeptides, fused to the C termini of Nm-fHbp and NHBA, were efficiently transported to the E. coli cell surface and compartmentalized in outer membrane vesicles, demonstrating that these lipoproteins can be exploited in biotechnological applications requiring Gram-negative bacterial surface display of foreign polypeptides.
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Affiliation(s)
- Laura Fantappiè
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Carmela Irene
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Micaela De Santis
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Alessandro Armini
- §Functional Proteomics Lab., Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Assunta Gagliardi
- §Functional Proteomics Lab., Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Michele Tomasi
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Matteo Parri
- ¶Toscana Life Sciences Scientific Park, Via Fiorentina, 1 53100, Siena, Italy
| | - Valeria Cafardi
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Serena Bonomi
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Luisa Ganfini
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Francesca Zerbini
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Ilaria Zanella
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy
| | - Chiara Carnemolla
- §Functional Proteomics Lab., Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Luca Bini
- §Functional Proteomics Lab., Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Alberto Grandi
- ¶Toscana Life Sciences Scientific Park, Via Fiorentina, 1 53100, Siena, Italy
| | - Guido Grandi
- From the ‡Synthetic and Structural Vaccinology Unit, CIBIO, University of Trento, Via Sommarive, 9, 38123 Povo, Trento, Italy;
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Toneatto D, Pizza M, Masignani V, Rappuoli R. Emerging experience with meningococcal serogroup B protein vaccines. Expert Rev Vaccines 2017; 16:433-451. [PMID: 28375029 DOI: 10.1080/14760584.2017.1308828] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The successful development of two broadly protective vaccines targeting Neisseria meningitidis serogroup B (MenB); 4CMenB and rLP2086, is the most significant recent advance in meningococcal disease prevention. Areas covered: Here we review the principles underlying the development of each vaccine and the novel methods used to estimate vaccine coverage. We update clinical and post-licensure experience with 4CMenB and rLP2086. Expert commentary: The immunogenicity and acceptable safety profile of 4CMenB and rLP2086 has been demonstrated in clinical trials. Continuing uncertainties exist around the appropriate age groups to be immunized, the degree and duration of efficacy, and the impact on nasopharyngeal carriage which has implications for strategies to interrupt transmission and maximize herd protection effects. Universal vaccination programs such as those undertaken in Quebec and the United Kingdom are providing important information on these issues. The potential for MenB vaccines to prevent infection by other serogroups appears promising, and the impact of MenB vaccines on other pathogenic neisserial species with similar surface proteins warrants further investigation.
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Shi F, Zhang A, Zhu B, Gao Y, Xu L, Li Y, Yin Z, Li J, Xie N, Shao Z. Prevalence of factor H Binding Protein sub-variants among Neisseria meningitidis in China. Vaccine 2017; 35:2343-2350. [PMID: 28351732 DOI: 10.1016/j.vaccine.2017.03.057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 01/21/2023]
Abstract
OBJECTIVE To study the prevalence of the fHbp genes in Neisseria meningitidis (N. meningitidis) isolates for further evaluation and development of serogroup B meningococcal vaccines in China. METHODS A panel of 1012 N. meningitidis strains was selected from the national culture collection from 1956 to 2016, according to the years of isolation, locations, and strain sources. These were tested by FHbp variant typing. Multi-locus sequence typing (MLST) was performed on 822 of these samples, including 242 strains from clinical strains and 580 carrier-derived strains. Analysis based on sequence types, serogroups, and FHbp variations were used to summarize the prevalence and characteristics of N. meningitidis. RESULTS There were 8 serogroups of N. meningitidis as well as a collection of nongroupable strains in this study. 1008 of 1012 N. meningitidis strains tested were positive for the fHbp gene. Serogroup A N. meningitidis (MenA) strains belonging to ST-1 and ST-5 clonal complexes harbored genes only encoding variant 1 (v1) FHbp. All MenW strains encoded v2 FHbp. 61.9% of clinical MenB strains were positive for v2 FHbp vs. 32.1% that were positive for v1. Among fHbp-positive carrier-derived MenB strains, v2 FHbp accounted for 90.8%. 79.7% of clinical MenC strains were positive for v1 FHbp and 20.3% were positive for v2 FHbp. Among carrier-derived MenC strains, v2 FHbp predominated. The number of major serogroups of N. meningitidis analyzed by MLST was 822, and the encoded FHbp showed CC- or ST-specific characteristics. CONCLUSION fHbp genes were detected in almost all N. meningitidis strains in this study. Therefore, it is possible that a vaccine against MenB or meningococci irrespective of serogroups, which includes FHbp, could be developed. Meningococcal vaccine development for China is a complex issue and these findings warrant further attention with respect to vaccine development.
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Affiliation(s)
- Fenglin Shi
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Aiyu Zhang
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Bingqing Zhu
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, People's Republic of China
| | - Yuan Gao
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Li Xu
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Yixing Li
- Department of National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Zundong Yin
- Department of National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Junhong Li
- Department of National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Na Xie
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China; School of Public Health, Xinjiang Medical University, Urumqi, Xinjiang, People's Republic of China; Center for Disease Control and Prevention of Xinjiang Uygur Autonomous Region, Urumqi, Xinjiang, People's Republic of China
| | - Zhujun Shao
- National Institute for Communicable Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, People's Republic of China.
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26
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Ganesh K, Allam M, Wolter N, Bratcher HB, Harrison OB, Lucidarme J, Borrow R, de Gouveia L, Meiring S, Birkhead M, Maiden MCJ, von Gottberg A, du Plessis M. Molecular characterization of invasive capsule null Neisseria meningitidis in South Africa. BMC Microbiol 2017; 17:40. [PMID: 28222677 PMCID: PMC5320719 DOI: 10.1186/s12866-017-0942-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 01/31/2017] [Indexed: 12/15/2022] Open
Abstract
Background The meningococcal capsule is an important virulence determinant. Unencapsulated meningococci lacking capsule biosynthesis genes and containing the capsule null locus (cnl) are predominantly non-pathogenic. Rare cases of invasive meningococcal disease caused by cnl isolates belonging to sequence types (ST) and clonal complexes (cc) ST-845 (cc845), ST-198 (cc198), ST-192 (cc192) and ST-53 (cc53) have been documented. The clinical significance of these isolates however remains unclear. We identified four invasive cnl meningococci through laboratory-based surveillance in South Africa from 2003 through 2013, which we aimed to characterize using whole genome data. Results One isolate [NG: P1.7-2,30: F1-2: ST-53 (cc53)] contained cnl allele 12, and caused empyema in an adult male with bronchiectasis from tuberculosis, diabetes mellitus and a smoking history. Three isolates were NG: P1.18-11,42-2: FΔ: ST-192 (cc192) and contained cnl allele 2. One patient was an adolescent male with meningitis. The remaining two isolates were from recurrent disease episodes (8 months apart) in a male child with deficiency of the sixth complement component, and with the exception of two single nucleotide polymorphisms, contained identical core genomes. The ST-53 (cc53) isolate possessed alleles for NHBA peptide 191 and fHbp variant 2; whilst the ST-192 (cc192) isolates contained NHBA peptide 704 and fHbp variant 3. All four isolates lacked nadA. Comparison of the South African genomes to 61 additional cnl genomes on the PubMLST Neisseria database (http://pubmlst.org/neisseria/), determined that most putative virulence genes could be found in both invasive and carriage phenotypes. Conclusions Although rare, invasive disease by cnl meningococci may be associated with host immunodeficiency and such patients may benefit from protein-based meningococcal vaccines. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-0942-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karistha Ganesh
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa. .,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Mushal Allam
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Nicole Wolter
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | | | - Jay Lucidarme
- Meningococcal Reference Unit, Public Health England, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary, Manchester, UK
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary, Manchester, UK
| | - Linda de Gouveia
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Susan Meiring
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Monica Birkhead
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | | | - Anne von Gottberg
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Mignon du Plessis
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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27
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Watkins ER, Maiden MC, Gupta S. Metabolic competition as a driver of bacterial population structure. Future Microbiol 2016; 11:1339-1357. [PMID: 27660887 DOI: 10.2217/fmb-2016-0079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Understanding the processes whereby diversity arises and is maintained in pathogen populations is pivotal for designing disease control interventions. A particular problem is the maintenance of strain structure in bacterial pathogen populations despite frequent genetic exchange. Although several theoretical frameworks have been put forward to explain this widespread phenomenon, few have focused on the role of genes encoding metabolic functions, despite an increasing recognition of their importance in pathogenesis and transmission. In this article, we review the literature for evidence of metabolic niches within the host and discuss theoretical frameworks which examine ecological interactions between metabolic genes. We contend that metabolic competition is an important phenomenon which contributes to the maintenance of population structure and diversity of many bacterial pathogens.
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Affiliation(s)
- Eleanor R Watkins
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - Martin Cj Maiden
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - Sunetra Gupta
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
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28
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Brehony C, Rodrigues CMC, Borrow R, Smith A, Cunney R, Moxon ER, Maiden MCJ. Distribution of Bexsero® Antigen Sequence Types (BASTs) in invasive meningococcal disease isolates: Implications for immunisation. Vaccine 2016; 34:4690-4697. [PMID: 27521232 PMCID: PMC5012890 DOI: 10.1016/j.vaccine.2016.08.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/01/2016] [Accepted: 08/03/2016] [Indexed: 01/19/2023]
Abstract
Serogroup B is the only major disease-associated capsular group of Neisseria meningitidis for which no protein-polysaccharide conjugate vaccine is available. This has led to the development of multi-component protein-based vaccines that target serogroup B invasive meningococcal disease (IMD), including Bexsero®, which was implemented for UK infants in 2015, and Trumenba®. Given the diversity of meningococcal protein antigens, post-implementation surveillance of IMD isolates, including characterisation of vaccine antigens, is essential for assessing the effectiveness of such vaccines. Whole genome sequencing (WGS), as realised in the Meningitis Research Foundation Meningococcus Genome Library (MRF-MGL), provides a rapid, comprehensive, and cost-effective approach to this. To facilitate the surveillance of the antigen targets included in Bexsero® (fHbp, PorA, NHBA and NadA) for protective immunity, a Bexsero® Antigen Sequence Type (BAST) scheme, based on deduced peptide sequence variants, was implemented in the PubMLST.org/neisseria database, which includes the MRF-MGL and other isolate collections. This scheme enabled the characterisation of vaccine antigen variants and here the invasive meningococci isolated in Great Britain and Ireland in the epidemiological years 2010/11 to 2013/14 are analysed. Many unique BASTs (647) were present, but nine of these accounted for 39% (775/1966) of isolates, with some temporal and geographic differences in BAST distribution. BASTs were strongly associated with other characteristics, such as serogroup and clonal complex (cc), and a significant increase in BAST-2 was associated with increased prevalence of serogroup W clonal complex 11 meningococci. Potential coverage was assessed by the examination of the antigen peptide sequences present in the vaccine and epidemiological dataset. There were 22.8-30.8% exact peptide matches to Bexsero® components and predicted coverage of 66.1%, based on genotype-phenotype modelling for 63.7% of serogroup B isolates from 2010/14 in UK and Ireland. While there are many caveats to this estimate, it lies within the range of other published estimates.
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Affiliation(s)
- Carina Brehony
- Department of Zoology, University of Oxford, South Parks Road, Oxford, United Kingdom.
| | | | - Ray Borrow
- Public Health England, Meningococcal Reference Unit, Manchester Royal Infirmary, Manchester, United Kingdom.
| | - Andrew Smith
- Scottish Haemophilus, Legionella, Meningococcus and Pneumococcus Reference Laboratory, Glasgow Royal Infirmary, Glasgow, United Kingdom; College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom.
| | - Robert Cunney
- Irish Meningitis and Meningococcal Reference Laboratory, Temple Street Children's University Hospital, Dublin, Ireland.
| | - E Richard Moxon
- Department of Paediatrics, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
| | - Martin C J Maiden
- Department of Zoology, University of Oxford, South Parks Road, Oxford, United Kingdom.
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29
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Gandhi A, Balmer P, York LJ. Characteristics of a new meningococcal serogroup B vaccine, bivalent rLP2086 (MenB-FHbp; Trumenba®). Postgrad Med 2016; 128:548-56. [PMID: 27467048 DOI: 10.1080/00325481.2016.1203238] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Neisseria meningitidis is a common cause of bacterial meningitis, often leading to permanent sequelae or death. N. meningitidis is classified into serogroups based on the composition of the bacterial capsular polysaccharide; the 6 major disease-causing serogroups are designated A, B, C, W, X, and Y. Four of the 6 disease-causing serogroups (A, C, Y, and W) can be effectively prevented with available quadrivalent capsular polysaccharide protein conjugate vaccines; however, capsular polysaccharide conjugate vaccines are not effective against meningococcal serogroup B (MnB). There is no vaccine available for serogroup X. The public health need for an effective serogroup B vaccine is evident, as MnB is the most common cause of meningococcal disease in the United States and is responsible for almost half of all cases in persons aged 17 to 22 years. In fact, serogroup B meningococci were responsible for the recent meningococcal disease outbreaks on college campuses. However, development of a suitable serogroup B vaccine has been challenging, as serogroup B polysaccharide-based vaccines were found to be poorly immunogenic. Vaccine development for MnB focused on identifying potential outer membrane protein targets that elicit broadly protective immune responses across strains from the vast number of proteins that exist on the bacterial surface. Human factor H binding protein (fHBP; also known as LP2086), a conserved surface-exposed bacterial lipoprotein, was identified as a promising vaccine candidate. Two recombinant protein-based serogroup B vaccines that contain fHBP have been successfully developed and licensed in the United States under an accelerated approval process: bivalent rLP2086 (MenB-FHbp; Trumenba®) and 4CMenB (MenB-4 C; Bexsero®). This review will focus on bivalent rLP2086 only, including vaccine components, mechanism of action, and potential coverage across serogroup B strains in the United States.
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Affiliation(s)
- Ashesh Gandhi
- a United States Medical and Scientific Affairs , Pfizer Vaccines , Collegeville , PA , USA
| | - Paul Balmer
- b Global Medical and Scientific Affairs , Pfizer Vaccines , Collegeville , PA , USA
| | - Laura J York
- b Global Medical and Scientific Affairs , Pfizer Vaccines , Collegeville , PA , USA
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30
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Brehony C, Hill DM, Lucidarme J, Borrow R, Maiden MC. Meningococcal vaccine antigen diversity in global databases. ACTA ACUST UNITED AC 2016; 20:30084. [PMID: 26676305 DOI: 10.2807/1560-7917.es.2015.20.49.30084] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 07/09/2015] [Indexed: 11/20/2022]
Abstract
The lack of an anti-capsular vaccine against serogroup B meningococcal disease has necessitated the exploration of alternative vaccine candidates, mostly proteins exhibiting varying degrees of antigenic variation. Analysis of variants of antigen-encoding genes is facilitated by publicly accessible online sequence repositories, such as the Neisseria PubMLST database and the associated Meningitis Research Foundation Meningococcus Genome Library (MRF-MGL). We investigated six proposed meningococcal vaccine formulations by deducing the prevalence of their components in the isolates represented in these repositories. Despite high diversity, a limited number of antigenic variants of each of the vaccine antigens were prevalent, with strong associations of particular variant combinations with given serogroups and genotypes. In the MRF-MGL and globally, the highest levels of identical sequences were observed with multicomponent/multivariant vaccines. Our analyses further demonstrated that certain combinations of antigen variants were prevalent over periods of decades in widely differing locations, indicating that vaccine formulations containing a judicious choice of antigen variants have potential for long-term protection across geographic regions. The data further indicated that formulations with multiple variants would be especially relevant at times of low disease incidence, as relative diversity was higher. Continued surveillance is required to monitor the changing prevalence of these vaccine antigens.
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Affiliation(s)
- Carina Brehony
- Department of Zoology, University of Oxford, South Parks Road, Oxford, United Kingdom
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31
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Cagliani R, Forni D, Filippi G, Mozzi A, De Gioia L, Pontremoli C, Pozzoli U, Bresolin N, Clerici M, Sironi M. The mammalian complement system as an epitome of host-pathogen genetic conflicts. Mol Ecol 2016; 25:1324-39. [PMID: 26836579 DOI: 10.1111/mec.13558] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/29/2015] [Accepted: 01/27/2016] [Indexed: 12/11/2022]
Abstract
The complement system is an innate immunity effector mechanism; its action is antagonized by a wide array of pathogens and complement evasion determines the virulence of several infections. We investigated the evolutionary history of the complement system and of bacterial-encoded complement-interacting proteins. Complement components targeted by several pathogens evolved under strong selective pressure in primates, with selection acting on residues at the contact interface with microbial/viral proteins. Positively selected sites in CFH and C4BPA account for the human specificity of gonococcal infection. Bacterial interactors, evolved adaptively as well, with selected sites located at interaction surfaces with primate complement proteins. These results epitomize the expectation under a genetic conflict scenario whereby the host's and the pathogen's genes evolve within binding avoidance-binding seeking dynamics. In silico mutagenesis and protein-protein docking analyses supported this by showing that positively selected sites, both in the host's and in the pathogen's interacting partner, modulate binding.
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Affiliation(s)
- Rachele Cagliani
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Diego Forni
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Giulia Filippi
- Department of Biotechnology and Biosciences, University of Milan-Bicocca, 20126, Milan, Italy
| | - Alessandra Mozzi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Luca De Gioia
- Department of Biotechnology and Biosciences, University of Milan-Bicocca, 20126, Milan, Italy
| | - Chiara Pontremoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Uberto Pozzoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Nereo Bresolin
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy.,Dino Ferrari Centre, Department of Physiopathology and Transplantation, University of Milan, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, 20122, Milan, Italy
| | - Mario Clerici
- Department of Physiopathology and Transplantation, University of Milan, 20090, Milan, Italy.,Don C. Gnocchi Foundation ONLUS, IRCCS, 20148, Milan, Italy
| | - Manuela Sironi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
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32
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Clark SA, Lekshmi A, Lucidarme J, Hao L, Tsao H, Lee-Jones L, Jansen KU, Newbold LS, Anderson AS, Borrow R. Differences between culture & non-culture confirmed invasive meningococci with a focus on factor H-binding protein distribution. J Infect 2016; 73:63-70. [PMID: 27025206 DOI: 10.1016/j.jinf.2016.03.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 02/24/2016] [Accepted: 03/17/2016] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To compare the distribution of capsular groups and factor H-binding protein (fHBP) variants among meningococcal isolates and non-culture clinical specimens and to assess the representativeness of group B isolates amongst group B cases as a whole. METHODS A PCR sequencing assay was used to characterise fHBP from non-culture cases confirmed from January 2011 to December 2013. These were compared to genotypic data derived from whole genome analysis of isolates received during the same period. RESULTS Group W and Y strains were more common among isolates than non-culture strains. The distribution of fHBP variants among group B non-culture cases generally reflected that seen in the corresponding isolates. Nonetheless, the non-culture subset contained a greater proportion of fHBP variant 15/B44, associated with the ST-269 cluster sublineage. CONCLUSIONS Differences in capsular group and fHBP distribution among culture and non-culture cases may be indicative of variation in strain viability, diagnostic practice, disease severity and/or clinical presentation. Future analyses combining clinical case information with laboratory data may help to further explore these differences. Group B isolates provide a good representation of group B disease in E&W and, therefore, can reliably be used in fHBP strain coverage predictions of recently-licensed vaccines.
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Affiliation(s)
- Stephen A Clark
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building II, Manchester Royal Infirmary, Manchester M13 9WZ, United Kingdom.
| | - Aiswarya Lekshmi
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building II, Manchester Royal Infirmary, Manchester M13 9WZ, United Kingdom.
| | - Jay Lucidarme
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building II, Manchester Royal Infirmary, Manchester M13 9WZ, United Kingdom.
| | - Li Hao
- Pfizer Vaccine Research, 401 N. Middletown Rd., Pearl River, NY 10965, United States.
| | - How Tsao
- Pfizer Vaccine Research, 401 N. Middletown Rd., Pearl River, NY 10965, United States.
| | - Lisa Lee-Jones
- Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester M1 5GD, United Kingdom.
| | - Kathrin U Jansen
- Pfizer Vaccine Research, 401 N. Middletown Rd., Pearl River, NY 10965, United States.
| | - Lynne S Newbold
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building II, Manchester Royal Infirmary, Manchester M13 9WZ, United Kingdom.
| | - Annaliesa S Anderson
- Pfizer Vaccine Research, 401 N. Middletown Rd., Pearl River, NY 10965, United States.
| | - Ray Borrow
- Vaccine Evaluation Unit, Public Health England, Clinical Sciences Building II, Manchester Royal Infirmary, Manchester M13 9WZ, United Kingdom.
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33
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Konar M, Pajon R, Beernink PT. A meningococcal vaccine antigen engineered to increase thermal stability and stabilize protective epitopes. Proc Natl Acad Sci U S A 2015; 112:14823-8. [PMID: 26627237 PMCID: PMC4672778 DOI: 10.1073/pnas.1507829112] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Factor H binding protein (FHbp) is part of two vaccines recently licensed for prevention of sepsis and meningitis caused by serogroup B meningococci. FHbp is classified in three phylogenic variant groups that have limited antigenic cross-reactivity, and FHbp variants in one of the groups have low thermal stability. In the present study, we replaced two amino acid residues, R130 and D133, in a stable FHbp variant with their counterparts (L and G) from a less stable variant. The single and double mutants decreased thermal stability of the amino- (N-) terminal domain compared with the wild-type protein as measured by scanning calorimetry. We introduced the converse substitutions, L130R and G133D, in a less stable wild-type FHbp variant, which increased the transition midpoint (Tm) for the N-terminal domain by 8 and 12 °C; together the substitutions increased the Tm by 21 °C. We determined the crystal structure of the double mutant FHbp to 1.6 Å resolution, which showed that R130 and D133 mediated multiple electrostatic interactions. Monoclonal antibodies specific for FHbp epitopes in the N-terminal domain had higher binding affinity for the recombinant double mutant by surface plasmon resonance and to the mutant expressed on meningococci by flow cytometry. The double mutant also had decreased binding of human complement Factor H, which in previous studies increased the protective antibody responses. The stabilized mutant FHbp thus has the potential to stabilize protective epitopes and increase the protective antibody responses to recombinant FHbp vaccines or native outer membrane vesicle vaccines with overexpressed FHbp.
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Affiliation(s)
- Monica Konar
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, University of California San Francisco Benioff Children's Hospital Oakland, Oakland, CA 94609
| | - Rolando Pajon
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, University of California San Francisco Benioff Children's Hospital Oakland, Oakland, CA 94609
| | - Peter T Beernink
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, University of California San Francisco Benioff Children's Hospital Oakland, Oakland, CA 94609
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34
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Araya P, Fernández J, Del Canto F, Seoane M, Ibarz-Pavón AB, Barra G, Pidal P, Díaz J, Hormazábal JC, Valenzuela MT. Neisseria meningitidis ST-11 clonal complex, Chile 2012. Emerg Infect Dis 2015; 21:339-41. [PMID: 25625322 PMCID: PMC4313638 DOI: 10.3201/eid2102.140746] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Serogroup W Neisseria meningitidis was the main cause of invasive meningococcal disease in Chile during 2012. The case-fatality rate for this disease was higher than in previous years. Genotyping of meningococci isolated from case-patients identified the hypervirulent lineage W:P1.5,2:ST-11, which contained allele 22 of the fHbp gene.
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35
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Foley J. Mini-review: Strategies for Variation and Evolution of Bacterial Antigens. Comput Struct Biotechnol J 2015; 13:407-16. [PMID: 26288700 PMCID: PMC4534519 DOI: 10.1016/j.csbj.2015.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 07/18/2015] [Accepted: 07/19/2015] [Indexed: 12/29/2022] Open
Abstract
Across the eubacteria, antigenic variation has emerged as a strategy to evade host immunity. However, phenotypic variation in some of these antigens also allows the bacteria to exploit variable host niches as well. The specific mechanisms are not shared-derived characters although there is considerable convergent evolution and numerous commonalities reflecting considerations of natural selection and biochemical restraints. Unlike in viruses, mechanisms of antigenic variation in most bacteria involve larger DNA movement such as gene conversion or DNA rearrangement, although some antigens vary due to point mutations or modified transcriptional regulation. The convergent evolution that promotes antigenic variation integrates various evolutionary forces: these include mutations underlying variant production; drift which could remove alleles especially early in infection or during life history phases in arthropod vectors (when the bacterial population size goes through a bottleneck); selection not only for any particular variant but also for the mechanism for the production of variants (i.e., selection for mutability); and overcoming negative selection against variant production. This review highlights the complexities of drivers of antigenic variation, in particular extending evaluation beyond the commonly cited theory of immune evasion. A deeper understanding of the diversity of purpose and mechanisms of antigenic variation in bacteria will contribute to greater insight into bacterial pathogenesis, ecology and coevolution with hosts.
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Affiliation(s)
- Janet Foley
- 1320 Tupper Hall, Veterinary Medicine and Epidemiology, UC Davis, Davis, CA 95616, United States
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Seib KL, Scarselli M, Comanducci M, Toneatto D, Masignani V. Neisseria meningitidis factor H-binding protein fHbp: a key virulence factor and vaccine antigen. Expert Rev Vaccines 2015; 14:841-59. [PMID: 25704037 DOI: 10.1586/14760584.2015.1016915] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Neisseria meningitidis is a leading cause of meningitis and sepsis worldwide. The first broad-spectrum multicomponent vaccine against serogroup B meningococcus (MenB), 4CMenB (Bexsero(®)), was approved by the EMA in 2013, for prevention of MenB disease in all age groups, and by the US FDA in January 2015 for use in adolescents. A second protein-based MenB vaccine has also been approved in the USA for adolescents (rLP2086, Trumenba(®)). Both vaccines contain the lipoprotein factor H-binding protein (fHbp). Preclinical studies demonstrated that fHbp elicits a robust bactericidal antibody response that correlates with the amount of fHbp expressed on the bacterial surface. fHbp is able to selectively bind human factor H, the key regulator of the alternative complement pathway, and this has important implications both for meningococcal pathogenesis and for vaccine design. Here, we review the functional and structural properties of fHbp, the strategies that led to the design of the two fHbp-based vaccines and the data generated during clinical studies.
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Affiliation(s)
- Kate L Seib
- Institute for Glycomics, Griffith University, Southport, Queensland, 4215, Australia
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Caesar JJE, Lavender H, Ward PN, Exley RM, Eaton J, Chittock E, Malik TH, Goiecoechea De Jorge E, Pickering MC, Tang CM, Lea SM. Competition between antagonistic complement factors for a single protein on N. meningitidis rules disease susceptibility. eLife 2014; 3. [PMID: 25534642 PMCID: PMC4273445 DOI: 10.7554/elife.04008] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 11/25/2014] [Indexed: 11/13/2022] Open
Abstract
Genome-wide association studies have found variation within the complement factor H gene family links to host susceptibility to meningococcal disease caused by infection with Neisseria meningitidis (Davila et al., 2010). Mechanistic insights have been challenging since variation within this locus is complex and biological roles of the factor H-related proteins, unlike factor H, are incompletely understood. N. meningitidis subverts immune responses by hijacking a host-immune regulator, complement factor H (CFH), to the bacterial surface (Schneider et al., 2006; Madico et al., 2007; Schneider et al., 2009). We demonstrate that complement factor-H related 3 (CFHR3) promotes immune activation by acting as an antagonist of CFH. Conserved sequences between CFH and CFHR3 mean that the bacterium cannot sufficiently distinguish between these two serum proteins to allow it to hijack the regulator alone. The level of protection from complement attack achieved by circulating N. meningitidis therefore depends on the relative levels of CFH and CFHR3 in serum. These data may explain the association between genetic variation in both CFH and CFHR3 and susceptibility to meningococcal disease.
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Affiliation(s)
- Joseph J E Caesar
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Hayley Lavender
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Philip N Ward
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Rachel M Exley
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Jack Eaton
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Emily Chittock
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Talat H Malik
- Centre for Complement and Inflammation Research, Department of Medicine, Imperial College, London, United Kingdom
| | - Elena Goiecoechea De Jorge
- Centre for Complement and Inflammation Research, Department of Medicine, Imperial College, London, United Kingdom
| | - Matthew C Pickering
- Centre for Complement and Inflammation Research, Department of Medicine, Imperial College, London, United Kingdom
| | - Christoph M Tang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Susan M Lea
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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Bratcher HB, Corton C, Jolley KA, Parkhill J, Maiden MCJ. A gene-by-gene population genomics platform: de novo assembly, annotation and genealogical analysis of 108 representative Neisseria meningitidis genomes. BMC Genomics 2014; 15:1138. [PMID: 25523208 PMCID: PMC4377854 DOI: 10.1186/1471-2164-15-1138] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/04/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Highly parallel, 'second generation' sequencing technologies have rapidly expanded the number of bacterial whole genome sequences available for study, permitting the emergence of the discipline of population genomics. Most of these data are publically available as unassembled short-read sequence files that require extensive processing before they can be used for analysis. The provision of data in a uniform format, which can be easily assessed for quality, linked to provenance and phenotype and used for analysis, is therefore necessary. RESULTS The performance of de novo short-read assembly followed by automatic annotation using the pubMLST.org Neisseria database was assessed and evaluated for 108 diverse, representative, and well-characterised Neisseria meningitidis isolates. High-quality sequences were obtained for >99% of known meningococcal genes among the de novo assembled genomes and four resequenced genomes and less than 1% of reassembled genes had sequence discrepancies or misassembled sequences. A core genome of 1600 loci, present in at least 95% of the population, was determined using the Genome Comparator tool. Genealogical relationships compatible with, but at a higher resolution than, those identified by multilocus sequence typing were obtained with core genome comparisons and ribosomal protein gene analysis which revealed a genomic structure for a number of previously described phenotypes. This unified system for cataloguing Neisseria genetic variation in the genome was implemented and used for multiple analyses and the data are publically available in the PubMLST Neisseria database. CONCLUSIONS The de novo assembly, combined with automated gene-by-gene annotation, generates high quality draft genomes in which the majority of protein-encoding genes are present with high accuracy. The approach catalogues diversity efficiently, permits analyses of a single genome or multiple genome comparisons, and is a practical approach to interpreting WGS data for large bacterial population samples. The method generates novel insights into the biology of the meningococcus and improves our understanding of the whole population structure, not just disease causing lineages.
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Boan P, Metasan N, Tempone S, Harnett G, Speers DJ, Keil AD. Neisseria meningitidis porA, fetA and fHbp gene distribution in Western Australia 2000 to 2011. BMC Infect Dis 2014; 14:686. [PMID: 25495685 PMCID: PMC4266217 DOI: 10.1186/s12879-014-0686-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 12/05/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND PorA, fetA and fHbp are three antigen encoding genes useful for meningococcal typing and FHbp is an important component of meningococcal B vaccines. METHODS We performed sequence analysis of meningococcal porA, fetA and fHbp genes on 128 isolates from Western Australia, relating results to age, gender, race and geographic region. RESULTS We found predominantly PorA subtypes P1.22,14-16 (n = 23) and P1.7-2,4 (n = 19); FetA subtypes F1-5 (n = 41), F3-6 (n = 11), F5-1 (n = 10), F5-2 (n = 9), F5-5 (n = 8), F3-3 (n = 8); and FHbp variant groups 1 (n = 65) and 2 (n = 44). PorA P1.22,14-16 and FHbp variant group 2 were associated with younger age and aboriginality. CONCLUSIONS FHbp modular groups of the bivalent recombinant FHbp vaccine and the multicomponent 4CMenB vaccine make up 8.3% and 47.7% respectively of the examined serogroup B isolates from 2000-2011, however to estimate vaccine efficacy requires an account of all vaccine antigens and their levels of expression.
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Affiliation(s)
- Peter Boan
- Department of Microbiology, PathWest Laboratory Medicine WA, Princess Margaret Hospital for Children, Roberts Road, Subiaco 6008, Australia.
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Role of factor H binding protein in Neisseria meningitidis virulence and its potential as a vaccine candidate to broadly protect against meningococcal disease. Microbiol Mol Biol Rev 2014; 77:234-52. [PMID: 23699256 DOI: 10.1128/mmbr.00056-12] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Neisseria meningitidis is a Gram-negative microorganism that exists exclusively in humans and can cause devastating invasive disease. Although capsular polysaccharide-based vaccines against serogroups A, C, Y, and W135 are widely available, the pathway to a broadly protective vaccine against serogroup B has been more complex. The last 11 years has seen the discovery and development of the N. meningitidis serogroup B (MnB) outer membrane protein factor H binding protein (fHBP) as a vaccine component. Since the initial discovery of fHBP, a tremendous amount of work has accumulated on the diversity, structure, and regulation of this important protein. fHBP has proved to be a virulence factor for N. meningitidis and a target for functional bactericidal antibodies. fHBP is critical for survival of meningococci in the human host, as it is responsible for the primary interaction with human factor H (fH). Binding of hfH by the meningococcus serves to downregulate the host alternative complement pathway and helps the organism evade host innate immunity. Preclinical studies have shown that an fHBP-based vaccine can elicit serum bactericidal antibodies capable of killing MnB, and the vaccine has shown very encouraging results in human clinical trials. This report reviews our current knowledge of fHBP. In particular, we discuss the recent advances in our understanding of fHBP, its importance to N. meningitidis, and its potential role as a vaccine for preventing MnB disease.
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Andrews SM, Pollard AJ. A vaccine against serogroup B Neisseria meningitidis: dealing with uncertainty. THE LANCET. INFECTIOUS DISEASES 2014; 14:426-34. [PMID: 24679664 DOI: 10.1016/s1473-3099(13)70341-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neisseria meningitidis is an important cause of invasive bacterial infection in children worldwide. Although serogroup C meningococcal disease has all but disappeared in the past decade as a direct result of immunisation programmes in Europe, Canada, and Australia, meningitis and septicaemia caused by serogroup B meningococci remain uncontrolled. A vaccine (4CMenB) has now been licensed for use in the European Union, comprising three immunogenic antigens (identified with use of reverse vaccinology) combined with bacterial outer-membrane vesicles. The vaccine has the potential to reduce mortality and morbidity associated with serogroup B meningococci infections, but uncertainty remains about the breadth of protection the vaccine might induce against the diverse serogroup B meningococci strains that cause disease. We discuss drawbacks in the techniques used to estimate coverage and potential efficacy of the vaccine, and their effects on estimates of cost-effectiveness, both with and without herd immunity. For parents, and clinicians treating individual patients, the predicted benefits of vaccination outweigh existing uncertainties if any cases can be prevented, but future use of the vaccine must be followed by rigorous post-implementation surveillance to reassess its value to health systems with directly recorded epidemiological data.
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Affiliation(s)
- Sophie M Andrews
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK
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Clark SA, Lucidarme J, Newbold LS, Borrow R. Genotypic analysis of meningococcal factor h-binding protein from non-culture clinical specimens. PLoS One 2014; 9:e89921. [PMID: 24587125 PMCID: PMC3933679 DOI: 10.1371/journal.pone.0089921] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/29/2014] [Indexed: 12/03/2022] Open
Abstract
Factor H-Binding Protein (fHbp) is an outer membrane protein antigen included in two novel meningococcal group B vaccines and, as such, is an important typing target. Approximately 50% of meningococcal disease cases in England and Wales are confirmed using real-time PCR on non-culture clinical specimens only. Protocols for typing fHbp from this subset of cases have not yet been established. Here we present a nested PCR-based assay designed to amplify and sequence fHbp from non-culture clinical specimens. From analytical sensitivity experiments carried out using diluted DNA extracts, an estimated analytical sensitivity limit of 6 fg/µL of DNA (<3 genome copies/µL) was calculated. The sensitivity of the assay was shown to be comparable to the ctrA-directed real-time PCR assay currently used to confirm invasive disease diagnoses from submitted clinical specimens. A panel of 96 diverse, patient-matched clinical specimen/isolate pairs from invasive disease cases was used to illustrate the breadth of strain coverage for the assay. All fHbp alleles sequenced from the isolates matched those derived from previous whole genome analyses. The first-round PCR primer binding sites are highly conserved, however an exceptional second-round PCR primer site mismatch in one validation isolate prevented amplification. In this case, amplification from the corresponding clinical specimen was achieved, suggesting that the use of a nested PCR procedure may compensate for any minor mismatches in round-two primer sites. The assay was successful at typing 91/96 (94.8%) of the non-culture clinical specimens in this study and exhibits sufficient sensitivity to type fHbp from the vast majority of non-culture clinical specimens received by the Meningococcal Reference Unit, Public Health England.
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Affiliation(s)
- Stephen A. Clark
- Manchester Medical Microbiology Partnership, Public Health England, Clinical Sciences Buildings, Manchester Royal Infirmary, Manchester, United Kingdom
- * E-mail:
| | - Jay Lucidarme
- Manchester Medical Microbiology Partnership, Public Health England, Clinical Sciences Buildings, Manchester Royal Infirmary, Manchester, United Kingdom
| | - Lynne S. Newbold
- Manchester Medical Microbiology Partnership, Public Health England, Clinical Sciences Buildings, Manchester Royal Infirmary, Manchester, United Kingdom
| | - Ray Borrow
- Manchester Medical Microbiology Partnership, Public Health England, Clinical Sciences Buildings, Manchester Royal Infirmary, Manchester, United Kingdom
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Panatto D, Amicizia D, Lai PL, Gasparini R. Neisseria meningitidisB vaccines. Expert Rev Vaccines 2014; 10:1337-51. [DOI: 10.1586/erv.11.103] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Barra GN, Araya PA, Fernandez JO, Gabastou JM, Hormazábal JC, Seoane M, Pidal PC, Valenzuela MT, Ibarz-Pavón AB. Molecular characterization of invasive Neisseria meningitidis strains isolated in Chile during 2010-2011. PLoS One 2013; 8:e66006. [PMID: 23776590 PMCID: PMC3679051 DOI: 10.1371/journal.pone.0066006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 05/01/2013] [Indexed: 11/18/2022] Open
Abstract
Background With the upcoming licensure of Outer Membrane Protein-based vaccines against meningococcal disease, data on disease incidence and molecular characteristic of circulating N. meningitidis strains in Latin American countries is needed. Chile is, to date, one of the few countries in the region that has performed this type of work in a comprehensive collection of disease-associated strains from two consecutive years, 2010–2011. Methods A total of 119 N. meningitidis strains isolated from patients with invasive disease in Chile in 2010–2011 were characterized by the National Reference Laboratory. Serogroup determination, MLST and porA typing were performed. Results Serogroup B was predominant in both study years, but W135 experienced a noticeable increase in 2011 compared to 2010. ST-11 complex, ST-41/44 complex ST-32 complex were the most prevalent among the isolates, and were strongly associated with serogroups W135 (ST-11 Complex) and B (ST-41/44 and ST-32 complexes). Likewise, the major porA types detected were strongly associated with these three clonal complexes: P1.5,2 was found exclusively among W135:ST-11 isolates, whereas P1.7, 2–3 was only detected in C:ST-11. ST-41/44 isolates mainly had P1.10-8, and ST-32 complex were associated with a P1.18-8 porA. Conclusions Our data show disease-associated N. meningitidis circulating in Chile are similar to those found in other parts of the world. The increase on W135:ST-11 isolates observed in 2011 foretold the unusual epidemiological situation experienced in the country in 2012, and MLST data show that this strain is indistinguishable from the one linked to the global Hajj 2000-related outbreak that occurred in 2001. Finally, this work demonstrates the importance of maintaining a strong national surveillance program integrating clinical, epidemiological and laboratory data and incorporating gold standard diagnostic and characterization techniques that allow the data to be compared all over the world.
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Affiliation(s)
- Gisselle N. Barra
- Sub-Department of Molecular Genetics, Institute of Public Health, Santiago, Chile
| | - Pamela A. Araya
- Section of Bacteriology, Institute of Public Health, Santiago, Chile
| | - Jorge O. Fernandez
- Sub-Department of Molecular Genetics, Institute of Public Health, Santiago, Chile
- * E-mail: (ABIP); (JF)
| | - Jean-Marc Gabastou
- Pan American Health Organization, Washington, D.C., United States of America
| | | | - Mabel Seoane
- Section of Bacteriology, Institute of Public Health, Santiago, Chile
| | - Paola C. Pidal
- Biomedical laboratory department, Institute of Public Health, Santiago, Chile
| | - Maria T. Valenzuela
- Biomedical laboratory department, Institute of Public Health, Santiago, Chile
| | - Ana Belén Ibarz-Pavón
- Pan American Health Organization, Washington, D.C., United States of America
- * E-mail: (ABIP); (JF)
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Delany I, Rappuoli R, Seib KL. Vaccines, reverse vaccinology, and bacterial pathogenesis. Cold Spring Harb Perspect Med 2013; 3:a012476. [PMID: 23637311 DOI: 10.1101/cshperspect.a012476] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Advances in genomics and innovative strategies such as reverse vaccinology have changed the concepts and approaches to vaccine candidate selection and design. Genome mining and blind selection of novel antigens provide a novel route to investigate the mechanisms that underpin pathogenesis. The resulting lists of novel candidates are revealing new aspects of pathogenesis of target organisms, which in turn drives the rational design of optimal vaccine antigens. Here we use the discovery, characterization, and exploitation of fHbp, a vaccine candidate and key virulence factor of meningococcus, as an illustrative case in point. Applying genomic approaches to study both the pathogen and host will ultimately increase our fundamental understanding of pathogen biology, mechanisms responsible for the development of protective immunity, and guide next-generation vaccine design.
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Affiliation(s)
- Isabel Delany
- Novartis Vaccines and Diagnostics, 53100 Siena, Italy
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Su YC, Hallström BM, Bernhard S, Singh B, Riesbeck K. Impact of sequence diversity in the Moraxella catarrhalis UspA2/UspA2H head domain on vitronectin binding and antigenic variation. Microbes Infect 2013; 15:375-87. [DOI: 10.1016/j.micinf.2013.02.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 01/15/2013] [Accepted: 02/11/2013] [Indexed: 12/31/2022]
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Donati C, Rappuoli R. Reverse vaccinology in the 21st century: improvements over the original design. Ann N Y Acad Sci 2013; 1285:115-32. [PMID: 23527566 DOI: 10.1111/nyas.12046] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Reverse vaccinology (RV), the first application of genomic technologies in vaccine research, represented a major revolution in the process of discovering novel vaccines. By determining their entire antigenic repertoire, researchers could identify protective targets and design efficacious vaccines for pathogens where conventional approaches had failed. Bexsero, the first vaccine developed using RV, has recently received positive opinion from the European Medicines Agency. The use of RV initiated a cascade of changes that affected the entire vaccine development process, shifting the focus from the identification of a list of vaccine candidates to the definition of a set of high throughput screens to reduce the need for costly and labor intensive tests in animal models. It is now clear that a deep understanding of the epidemiology of vaccine candidates, and their regulation and role in host-pathogen interactions, must become an integral component of the screening workflow. Far from being outdated by technological advancements, RV still represents a paradigm of how high-throughput technologies and scientific insight can be integrated into biotechnology research.
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ZnuD, a potential candidate for a simple and universal Neisseria meningitidis vaccine. Infect Immun 2013; 81:1915-27. [PMID: 23509142 DOI: 10.1128/iai.01312-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neisseria meningitidis serogroup B (MenB) is a major cause of bacterial sepsis and meningitis, with the highest disease burden in young children. Available vaccines are based on outer membrane vesicles (OMVs) obtained from wild-type strains. However, particularly in toddlers and infants, they confer protection mostly against strains expressing the homologous protein PorA, a major and variable outer membrane protein. In the quest for alternative vaccine antigens able to provide broad MenB strain coverage in younger populations, but potentially also across all age groups, ZnuD, a protein expressed under zinc-limiting conditions, may be considered a promising candidate. Here, we have investigated the potential value of ZnuD and show that it is a conserved antigen expressed by all MenB strains tested except for some strains of clonal complex ST-8. In mice and guinea pigs immunized with ZnuD-expressing OMVs, antibodies were elicited that were able to trigger complement-mediated killing of all the MenB strains and serogroup A, C, and Y strains tested when grown under conditions of zinc limitation. ZnuD is also expressed during infection, since anti-ZnuD antibodies were detected in sera from patients. In conclusion, we confirm the potential of ZnuD-bearing OMVs as a component of an effective MenB vaccine.
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Sorhouet-Pereira C, Efron A, Gagetti P, Faccone D, Regueira M, Corso A, Gabastou JM, Ibarz-Pavón AB. Phenotypic and genotypic characteristics of Neisseria meningitidis disease-causing strains in Argentina, 2010. PLoS One 2013; 8:e58065. [PMID: 23483970 PMCID: PMC3587574 DOI: 10.1371/journal.pone.0058065] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 01/29/2013] [Indexed: 11/19/2022] Open
Abstract
Phenotypic and genotypic characterization of 133 isolates of Neisseria meningitidis obtained from meningococcal disease cases in Argentina during 2010 were performed by the National Reference Laboratory as part of a project coordinated by the PAHO within the SIREVA II network. Serogroup, serotype, serosubtype and MLST characterization were performed. Minimum Inhibitory Concentration to penicillin, ampicillin, ceftriaxone, rifampin, chloramphenicol, tetracycline and ciprofloxacin were determined and interpreted according to CLSI guidelines. Almost 49% of isolates were W135, and two serotype:serosubtype combinations, W135:2a:P1.5,2:ST-11 and W135:2a:P1.2:ST-11 accounted for 78% of all W135 isolates. Serogroup B accounted for 42.1% of isolates, and was both phenotypically and genotypically diverse. Serogroup C isolates represented 5.3% of the dataset, and one isolate belonging to the ST-198 complex was non-groupable. Isolates belonged mainly to the ST-11 complex (48%) and to a lesser extent to the ST-865 (18%), ST-32 (9,8%) and the ST-35 complexes (9%). Intermediate resistance to penicillin and ampicillin was detected in 35.4% and 33.1% of isolates respectively. Two W135:2a:P1.5,2:ST-11:ST-11 isolates presented resistance to ciprofloxacin associated with a mutation in the QRDR of gyrA gene Thr91-Ile. These data show serogroup W135 was the first cause of disease in Argentina in 2010, and was strongly associated with the W135:2a:P1.5,2:ST-11 epidemic clone. Serogroup B was the second cause of disease and isolates belonging to this serogroup were phenotypically and genotypically diverse. The presence of isolates with intermediate resistance to penicillin and the presence of fluorquinolone-resistant isolates highlight the necessity and importance of maintaining and strengthening National Surveillance Programs.
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Affiliation(s)
- Cecilia Sorhouet-Pereira
- Clinical Bacteriology Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | - Adriana Efron
- Clinical Bacteriology Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | - Paula Gagetti
- Antimicrobial Resistance Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | - Diego Faccone
- Antimicrobial Resistance Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | - Mabel Regueira
- Clinical Bacteriology Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | - Alejandra Corso
- Antimicrobial Resistance Service, Department of Bacteriology, National Institute for Infectious Diseases (ANLIS-INEI), ‘Dr Carlos G. Malbrán’, Ministry of Health, Buenos Aires, Argentina
| | | | - Jean-Marc Gabastou
- Pan American Health Organization, Washington, DC, United States of America
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50
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Abstract
Meningococcal meningitis and septicaemia remain a serious global health threat. This review focuses on the epidemiology of meningococcal disease following the recent implementation of effective vaccines and the potential utility of a vaccine against serogroup B meningococcus.
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Affiliation(s)
- Simon Nadel
- Department of Paediatric Intensive Care, St Marys Hospital, Praed Street, London, UK.
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