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Expression of factor H binding protein in meningococcal strains can vary at least 15-fold and is genetically determined. Proc Natl Acad Sci U S A 2016; 113:2714-9. [PMID: 26888286 DOI: 10.1073/pnas.1521142113] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Factor H binding protein (fHbp) is a lipoprotein of Neisseria meningitidis important for the survival of the bacterium in human blood and a component of two recently licensed vaccines against serogroup B meningococcus (MenB). Based on 866 different amino acid sequences this protein is divided into three variants or two families. Quantification of the protein is done by immunoassays such as ELISA or FACS that are susceptible to the sequence variation and expression level of the protein. Here, selected reaction monitoring mass spectrometry was used for the absolute quantification of fHbp in a large panel of strains representative of the population diversity of MenB. The analysis revealed that the level of fHbp expression can vary at least 15-fold and that variant 1 strains express significantly more protein than variant 2 or variant 3 strains. The susceptibility to complement-mediated killing correlated with the amount of protein expressed by the different meningococcal strains and this could be predicted from the nucleotide sequence of the promoter region. Finally, the absolute quantification allowed the calculation of the number of fHbp molecules per cell and to propose a mechanistic model of the engagement of C1q, the recognition component of the complement cascade.
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Immunization with a 22-kDa outer membrane protein elicits protective immunity to multidrug-resistant Acinetobacter baumannii. Sci Rep 2016; 6:20724. [PMID: 26853590 PMCID: PMC4745112 DOI: 10.1038/srep20724] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 01/11/2016] [Indexed: 11/28/2022] Open
Abstract
A. baumannii infections are becoming more and more serious health issues with rapid emerging of multidrug and extremely drug resistant strains, and therefore, there is an urgent need for the development of nonantibiotic-based intervention strategies. This study aimed at identifying whether an outer membrane protein with molecular weight of about 22 kDa (Omp22) holds the potentials to be an efficient vaccine candidate and combat A. baumannii infection. Omp22 which has a molecule length of 217 amino acids kept more than 95% conservation in totally 851 reported A. baumannii strains. Recombinant Omp22 efficiently elicited high titers of specific IgG in mice. Both active and passive immunizations of Omp22 increased the survival rates of mice, suppressed the bacterial burdens in the organs and peripheral blood, and reduced the levels of serum inflammatory cytokines and chemokines. Opsonophagocytosis assays showed in vitro that Omp22 antiserum had highly efficient bactericidal activities on clonally distinct clinical A. baumannii isolates, which were partly complements-dependent and opsonophagocytic killing effects. Additionally, administration with as high as 500 μg of Omp22 didn’t cause obvious pathological changes in mice. In conclusion, Omp22 is a novel conserved and probably safe antigen for developing effective vaccines or antisera to control A. baumannii infections.
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A phase 3, randomized, active-controlled study to assess the safety and tolerability of meningococcal serogroup B vaccine bivalent rLP2086 in healthy adolescents and young adults. Vaccine 2016; 34:1465-71. [PMID: 26845739 DOI: 10.1016/j.vaccine.2016.01.044] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 01/14/2016] [Accepted: 01/19/2016] [Indexed: 11/22/2022]
Abstract
BACKGROUND Neisseria meningitidis serogroup B (MnB) is an important cause of invasive meningococcal disease (IMD). A MnB vaccine (bivalent rLP2086, Trumenba(®)) consisting of 2 factor H binding protein variants received accelerated approval in the United States for the prevention of IMD caused by MnB in individuals 10-25 years of age. This randomized, active-controlled, observer-blind study further assessed the safety and tolerability of bivalent rLP2086. METHODS Eligible subjects ≥ 10 to < 26 years were randomized (2:1) to receive bivalent rLP2086 at months 0, 2, and 6, or hepatitis A virus vaccine (HAV, Havrix(®)) at months 0 and 6, and saline at month 2. The primary endpoints were serious adverse events (SAEs) throughout the study and medically-attended adverse events (MAEs) within 30 days after vaccination. Additional safety assessments included SAEs at other study intervals and adverse events (AEs) during the vaccination phase. RESULTS Of 5712 subjects randomized, 84.6% (n = 3219) of bivalent rLP2086 recipients and 87.2% (n = 1663) of HAV/saline recipients completed the study. Throughout the study, SAEs were reported for 1.6% and 2.5% of bivalent rLP2086 and HAV/saline recipients, respectively. SAEs related to either vaccine were rare. MAEs occurred in 7.0% and 6.1% of subjects after vaccination 1; 5.5% and 6.1% after vaccination 2; and 5.3% and 5.5% after vaccination 3 in the bivalent rLP2086 and HAV/saline groups, respectively. A greater proportion of subjects reported AEs during the vaccination phase after bivalent rLP2086 compared with HAV/saline recipients; however, when reactogenicity events were excluded, the proportion between groups was similar. CONCLUSION This safety study, the largest randomized, active-controlled trial evaluating a recombinant MnB vaccine, demonstrated that bivalent rLP2086 is safe and tolerable in healthy individuals ≥ 10 to < 26 years of age.
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Immunogenicity, safety, and tolerability of the meningococcal serogroup B bivalent rLP2086 vaccine in adult laboratory workers. Vaccine 2016; 34:809-13. [DOI: 10.1016/j.vaccine.2015.12.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 12/02/2015] [Accepted: 12/08/2015] [Indexed: 11/21/2022]
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105
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Salverda MLM, Meinderts SM, Hamstra HJ, Wagemakers A, Hovius JWR, van der Ark A, Stork M, van der Ley P. Surface display of a borrelial lipoprotein on meningococcal outer membrane vesicles. Vaccine 2016; 34:1025-33. [PMID: 26801064 DOI: 10.1016/j.vaccine.2016.01.019] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 12/09/2015] [Accepted: 01/11/2016] [Indexed: 12/12/2022]
Abstract
Outer Membrane Vesicles (OMVs) are gaining attention as vaccine candidates. The successful expression of heterologous antigens in OMVs, with the OMV functioning both as adjuvant and delivery vehicle, has greatly enhanced their vaccine potential. Since there are indications that surface exposed antigens might induce a superior immune response, targeting of heterologous antigens to the OMV surface is of special interest. Several systems for surface display of heterologous antigens on OMVs have been developed. However, these systems have not been used to display lipidated membrane-associated proteins known as lipoproteins, which are emerging as key targets for protective immunity. We were therefore interested to see whether we could express a foreign lipoprotein on the outer surface of OMVs. When outer surface protein A (OspA), a borrelial surface-exposed lipoprotein, was expressed in meningococci, it was found that although OspA was present in OMVs, it was no longer surface-exposed. Therefore, a set of fusions of OspA to different regions of factor H binding protein (fHbp), a meningococcal surface-exposed lipoprotein, were designed and tested for their surface-exposure. An N-terminal part of fHbp was found to be necessary for the successful surface display of OspA on meningococcal OMVs. When mice were immunized with this set of OMVs, an OspA-specific antibody response was only elicited by OMVs with clearly surface-exposed OspA, strengthening the idea that the exact positioning of an antigen in the OMV affects the immune response. This method for the surface display of heterologous lipoproteins on OMVs is a step forward in the development of OMVs as a vaccine platform.
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Affiliation(s)
- Merijn L M Salverda
- Institute for Translational Vaccinology (InTraVacc), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands.
| | - Sanne M Meinderts
- Institute for Translational Vaccinology (InTraVacc), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Hendrik-Jan Hamstra
- Immunology of Infectious Diseases and Vaccines (IIV), National Institute of Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Alex Wagemakers
- Department of Internal Medicine, Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Joppe W R Hovius
- Department of Internal Medicine, Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Arno van der Ark
- Institute for Translational Vaccinology (InTraVacc), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Michiel Stork
- Institute for Translational Vaccinology (InTraVacc), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Peter van der Ley
- Institute for Translational Vaccinology (InTraVacc), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
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Green LR, Eiden J, Hao L, Jones T, Perez J, McNeil LK, Jansen KU, Anderson AS. Approach to the Discovery, Development, and Evaluation of a Novel Neisseria meningitidis Serogroup B Vaccine. Methods Mol Biol 2016; 1403:445-469. [PMID: 27076147 DOI: 10.1007/978-1-4939-3387-7_25] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this chapter, we describe a research and development pathway to identify and demonstrate the efficacy of a Neisseria meningitidis non-capsular vaccine, the recently licensed N. meningitidis serogroup B (MnB) vaccine, Trumenba(®). While other approaches have been followed in the identification of a MnB vaccine (Pizza et al. Science 287:1816-1820, 2000), the methods described here reflect the distinctive approach and experiences in discovering and developing Trumenba(®). In contrast to the development and licensure of polysaccharide-conjugate vaccines against meningococcal serotypes A, C, W, and Y, the development of a vaccine to produce broadly protective antibodies against meningococcal serogroup B has proved difficult, due to the antigenic mimicry of the serogroup B polysaccharide capsule, which is composed of polysialic acid structures similar to those expressed on human neuronal cells. Early development efforts for these vaccines failed because the MnB polysaccharide structures resemble autoantigens and thus were poorly immunogenic. The development of an MnB vaccine has therefore focused on non-polysaccharide approaches. It was critical to identify MnB cell surface-exposed antigens capable of inducing a protective response against diverse, circulating strains of invasive MnB to ensure global coverage. Once candidate antigens were identified, it was important to characterize antigenic variation and expression levels, and subsequently to assure that antigens were expressed broadly among diverse clinical isolates. Prior to the initiation of clinical trials in humans, candidate vaccine antigens were tested in functional immunogenicity assays and yielded responses that were correlated with protection from meningococcal disease. These functional immunogenicity assays (serum bactericidal assays using human complement, hSBAs) measure the titer of complement-dependent bactericidal antibodies in serum from immunized test animals using diverse clinical MnB isolates as targets. Following optimization of vaccine antigenic components based on hSBA responses in preclinical models, animal toxicology tests were performed. Initial clinical studies (Phase 1 and 2) subsequently provided data to support (1) safety and immunogenicity of the vaccine formulation, and (2) the dose and schedule. Phase 3 clinical trials were carried out in the target populations to provide the clinical confirmation of safety and efficacy required for vaccine licensure.
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Affiliation(s)
- Luke R Green
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Joseph Eiden
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Li Hao
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Tom Jones
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - John Perez
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Lisa K McNeil
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Kathrin U Jansen
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA
| | - Annaliesa S Anderson
- Pfizer Vaccine Research and Development Unit, 401 North Middletown Road, Pearl River, NY, USA.
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Wilson MM, Bernstein HD. Surface-Exposed Lipoproteins: An Emerging Secretion Phenomenon in Gram-Negative Bacteria. Trends Microbiol 2015; 24:198-208. [PMID: 26711681 DOI: 10.1016/j.tim.2015.11.006] [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] [Received: 09/28/2015] [Revised: 11/17/2015] [Accepted: 11/23/2015] [Indexed: 01/07/2023]
Abstract
Bacterial lipoproteins are hydrophilic proteins that are anchored to a cell membrane by N-terminally linked fatty acids. It is widely believed that nearly all lipoproteins produced by Gram-negative bacteria are either retained in the inner membrane (IM) or transferred to the inner leaflet of the outer membrane (OM). Lipoproteins that are exposed on the cell surface have also been reported but are generally considered to be rare. Results from a variety of recent studies, however, now suggest that the prevalence of surface-exposed lipoproteins has been underestimated. In this review we describe the evidence that the surface exposure of lipoproteins in Gram-negative bacteria is a widespread phenomenon and discuss possible mechanisms by which these proteins might be transported across the OM.
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Affiliation(s)
- Marlena M Wilson
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Harris D Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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108
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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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Susceptibility of Meningococcal Strains Responsible for Two Serogroup B Outbreaks on U.S. University Campuses to Serum Bactericidal Activity Elicited by the MenB-4C Vaccine. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:1227-34. [PMID: 26424832 DOI: 10.1128/cvi.00474-15] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/28/2015] [Indexed: 12/12/2022]
Abstract
In 2013 and 2014, two U.S. universities had meningococcal serogroup B outbreaks (a total of 14 cases) caused by strains from two different clonal complexes. To control the outbreaks, students were immunized with a serogroup B meningococcal vaccine (Novartis) that was not yet licensed in the United States. The vaccine (referred to as MenB-4C) contains four components capable of eliciting bactericidal activity. Both outbreak strains had high expression levels of two of the vaccine antigens (subfamily B factor H binding protein [FHbp] and neisserial heparin binding antigen [NHba]); the university B outbreak strain also had moderate expression of a third antigen, NadA. We investigated the bactericidal activity of sera from mice immunized with FHbp, NHba, or NadA and sera from MenB-4C-immunized infant macaques and an adult human. The postimmunization bactericidal activity of the macaque or human serum against isolates from university B with FHbp identification (ID) 1 that exactly matched the vaccine FHbp sequence variant was 8- to 21-fold higher than that against isolates from university A with FHbp ID 276 (96% identity to the vaccine antigen). Based on the bactericidal activity of mouse antisera to FHbp, NadA, or NHba and macaque or human postimmunization serum that had been depleted of anti-FHbp antibody, the bactericidal activity against both outbreak strains largely or entirely resulted from antibodies to FHbp. Thus, despite the high level of strain expression of FHbp from a subfamily that matched the vaccine antigen, there can be large differences in anti-FHbp bactericidal activity induced by MenB-4C vaccination. Further, strains with moderate to high NadA and/or NHba expression can be resistant to anti-NadA or anti-NHba bactericidal activity elicited by MenB-4C vaccination.
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110
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Leng CH, Liu SJ, Chen HW, Chong P. Recombinant bacterial lipoproteins as vaccine candidates. Expert Rev Vaccines 2015; 14:1623-32. [PMID: 26420467 DOI: 10.1586/14760584.2015.1091732] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recombinant bacterial lipoproteins (RLP) with built-in immuno-stimulating properties for novel subunit vaccine development are reviewed. This platform technology offers the following advantages: easily converts antigens into highly immunogenic RLP using a fusion sequence containing lipobox; the lipid moiety of RLP is recognized as the danger signals in the immune system through the Toll-like receptor 2, so both innate and adaptive immune responses can be induced by RLP; serves as an efficient and cost-effective bioprocess for producing RLP in Escherichia coli and the feasibility and safety of this core platform technology has been successfully demonstrated in animal model studies including meningococcal group B subunit vaccine, dengue subunit vaccine, novel subunit vaccine against Clostridium difficile-associated diseases and HPV-based immunotherapeutic vaccines.
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Affiliation(s)
- Chih-Hsiang Leng
- a Vaccine R&D Center, National Health Research Institutes, Zhunan Town, Miaoli 350, Taiwan
| | - Shih-Jen Liu
- a Vaccine R&D Center, National Health Research Institutes, Zhunan Town, Miaoli 350, Taiwan
| | - Hsin-Wei Chen
- a Vaccine R&D Center, National Health Research Institutes, Zhunan Town, Miaoli 350, Taiwan
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Gasparini R, Panatto D, Bragazzi NL, Lai PL, Bechini A, Levi M, Durando P, Amicizia D. How the Knowledge of Interactions between Meningococcus and the Human Immune System Has Been Used to Prepare Effective Neisseria meningitidis Vaccines. J Immunol Res 2015; 2015:189153. [PMID: 26351643 PMCID: PMC4553322 DOI: 10.1155/2015/189153] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 06/09/2015] [Indexed: 01/17/2023] Open
Abstract
In the last decades, tremendous advancement in dissecting the mechanisms of pathogenicity of Neisseria meningitidis at a molecular level has been achieved, exploiting converging approaches of different disciplines, ranging from pathology to microbiology, immunology, and omics sciences (such as genomics and proteomics). Here, we review the molecular biology of the infectious agent and, in particular, its interactions with the immune system, focusing on both the innate and the adaptive responses. Meningococci exploit different mechanisms and complex machineries in order to subvert the immune system and to avoid being killed. Capsular polysaccharide and lipooligosaccharide glycan composition, in particular, play a major role in circumventing immune response. The understanding of these mechanisms has opened new horizons in the field of vaccinology. Nowadays different licensed meningococcal vaccines are available and used: conjugate meningococcal C vaccines, tetravalent conjugate vaccines, an affordable conjugate vaccine against the N. menigitidis serogroup A, and universal vaccines based on multiple antigens each one with a different and peculiar function against meningococcal group B strains.
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Affiliation(s)
- R. Gasparini
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - D. Panatto
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - N. L. Bragazzi
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - P. L. Lai
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - A. Bechini
- Department of Health Sciences, University of Florence, Viale G.B. Morgagni 48, 50134 Florence, Italy
| | - M. Levi
- Department of Health Sciences, University of Florence, Viale G.B. Morgagni 48, 50134 Florence, Italy
| | - P. Durando
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - D. Amicizia
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
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112
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Meningococcal Antigen Typing System Development and Application to the Evaluation of Effectiveness of Meningococcal B Vaccine and Possible Use for Other Purposes. J Immunol Res 2015; 2015:353461. [PMID: 26351645 PMCID: PMC4553328 DOI: 10.1155/2015/353461] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/16/2015] [Accepted: 02/17/2015] [Indexed: 01/22/2023] Open
Abstract
Development of the 4-component meningococcal serogroup B vaccine (4CMenB) has required new assays for the reliable evaluation of the expression and cross-reactivity of those specific antigen variants that are predicted to be targeted by bactericidal antibodies elicited by the vaccine in different isolates. Existing laboratory techniques, such as multilocus sequence typing, are poorly suited to this purpose, since they do not provide information on the contribution of single vaccine components and therefore cannot be applied to estimate the potential coverage of the multicomponent vaccine. The hSBA, the only correlate of protection against invasive meningococcal disease accepted thus far, cannot conveniently be used to test large number of strains. To overcome these issues, the meningococcal antigen typing system (MATS) has been specifically developed in order to predict 4CMenB coverage of individual meningococcus serogroup B strains. To date, MATS has proved advantageous for several reasons, including its ability to assess both qualitative and quantitative aspects of surface antigens of single strains in a highly reproducible, rapid, and resource-saving manner, while its shortcomings include a possible underestimation of 4CMenB coverage and the use of pooled sera to calculate the positive bactericidal threshold. This paper provides an overview of MATS development and its field application.
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113
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GASPARINI R, AMICIZIA D, LAI P, PANATTO D. Meningococcal B vaccination strategies and their practical application in Italy. JOURNAL OF PREVENTIVE MEDICINE AND HYGIENE 2015; 56:E133-9. [PMID: 26788734 PMCID: PMC4755122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 08/31/2015] [Indexed: 10/31/2022]
Abstract
Immunisation against meningococcal meningitis has a long history, which has passed through several phases: the studies by Flexner, extraction of the polysaccharide capsule, the development of monovalent and multivalent conjugate vaccines, the outer membrane vesicle vaccines up to the development of effective and safe vaccines for meningococcal B invasive disease through the application of the techniques of molecular biology and reverse vaccinology. The new available vaccines are Bexsero® and Trumenba®. Bexsero ® has been approved and is available in Europe, the USA, Canada, Australia and Chile, and is currently under review in Brazil for the prevention of MenB invasive disease in subjects ≥ 2 months. Trumemba® is currently approved only in the USA, for use in adolescents and young adults. At present, the greatest obstacle to the extensive use of these vaccines in industrialised countries is the high cost and the need administer multiple doses in infants. However, in some European countries and in some Italian Regions, strategies (free and active call) to fight the disease through vaccination (Bexsero®) are already in place.
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Affiliation(s)
- R. GASPARINI
- Correspondence: Roberto Gasparini, Department of Health Sciences, Genoa University, via Pastore, 1, 16132 Genova, Italy - Tel. +39 010 3538527 - Fax +39 010 3538541 - E-mail:
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Perrett KP, McVernon J, Richmond PC, Marshall H, Nissen M, August A, Percell S, Toneatto D, Nolan T. Immune responses to a recombinant, four-component, meningococcal serogroup B vaccine (4CMenB) in adolescents: a phase III, randomized, multicentre, lot-to-lot consistency study. Vaccine 2015; 33:5217-24. [PMID: 26232542 DOI: 10.1016/j.vaccine.2015.06.103] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 06/26/2015] [Accepted: 06/27/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND For decades, a broadly effective vaccine against serogroup B Neisseria meningitidis (MenB) has remained elusive. Recently, a four-component recombinant vaccine (4CMenB) has been developed and is now approved in Europe, Canada, Australia and some Latin American countries. This phase III, randomized study evaluated the lot consistency, early immune responses and the safety profile of 4CMenB in 11 to 17-year-old adolescents in Australia and Canada (NCT01423084). METHODS In total, 344 adolescents received two doses of one of 2 lots of 4CMenB, 1-month apart. Immunogenicity was assessed before, 2-weeks and 1-month following the second vaccination. Serum bactericidal activity using human complement (hSBA) was measured against three reference strains 44/76-SL, 5/99 and NZ98/254, selected to express one of the vaccine antigens; Neisseria adhesin A (NadA), factor H binding protein (fHbp) and porin A (PorA) containing outer membrane vesicle (OMV), respectively. Responses to the Neisseria heparin binding antigen (NHBA) were assessed with enzyme linked immunosorbent assay (ELISA). Local and systemic reactions were recorded for 7 days following each vaccination; unsolicited adverse events were monitored throughout the study. RESULTS Immunological equivalence of the two lots of 4CMenB was established at 1-month. At baseline, ≤7% of participants had hSBA titers ≥5 to all three reference strains. Two weeks following the second dose of 4CMenB, all participants had hSBA titers ≥5 against fHbp and NadA compared with 84-96% against the PorA reference strains. At 1-month, corresponding proportions were 99%, 100% and 70-79%, respectively. Both lots were generally well tolerated and had similar adverse event profiles. CONCLUSIONS Two doses of 4CMenB had an acceptable safety profile and induced a robust immune response in adolescents. Peak antibody responses were observed at 14 days following vaccination. While a substantial non-uniform antigen-dependent early decline in antibody titers was seen thereafter, a significant percentage of participants continued to maintain protective hSBA titers at 1-month.
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Affiliation(s)
- Kirsten P Perrett
- Vaccine and Immunisation Research Group (VIRGo), Murdoch Childrens Research Institute and Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Jodie McVernon
- Vaccine and Immunisation Research Group (VIRGo), Murdoch Childrens Research Institute and Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Peter C Richmond
- School of Paediatrics and Child Health, University of Western Australia, Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, Princess Margaret Hospital for Children, Perth, Australia
| | - Helen Marshall
- Vaccinology and Immunology Research Trials Unit (VIRTU), Women's and Children's Hospital, School of Paediatrics and Reproductive Health and Robinson Research Institute, The University of Adelaide, Adelaide, Australia
| | - Michael Nissen
- Queensland Paediatric Infectious Diseases Laboratory (Qpid), Queensland Children's Medical Research Institute, Royal Children's Hospital, University of Queensland, Brisbane, Australia
| | - Allison August
- Novartis Vaccines and Diagnostics Inc., Cambridge, MA, USA
| | - Sandra Percell
- Novartis Vaccines and Diagnostics Inc., Cambridge, MA, USA
| | | | - Terry Nolan
- Vaccine and Immunisation Research Group (VIRGo), Murdoch Childrens Research Institute and Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia.
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Law DKS, Lefebvre B, Gilca R, Deng S, Zhou J, De Wals P, Tsang RSW. Characterization of invasive Neisseria meningitidis strains from Québec, Canada, during a period of increased serogroup B disease, 2009-2013: phenotyping and genotyping with special emphasis on the non-carbohydrate protein vaccine targets. BMC Microbiol 2015; 15:143. [PMID: 26204985 PMCID: PMC4514445 DOI: 10.1186/s12866-015-0469-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/19/2015] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The epidemiology of invasive meningococcal disease (IMD) in Québec, Canada, has been dominated in the past decade by a clone of serogroup B (MenB) Neisseria meningitidis defined by multi-locus sequence typing (MLST) as sequence type (ST)-269. With the licensure of a new MenB vaccine Bexsero (4CMenB) in Canada, this study characterized invasive N. meningitidis recovered in Québec from 2009 to 2013, with an objective to examine the diversity of the 4CMenB vaccine antigens. Isolates were serogrouped by antisera and genogrouped by PCR, and further typed by whole cell ELISA for serotype and serosubtype antigens. Clonal analysis was done by MLST. Isolates were genotyped by analysis of their 4CMenB vaccine antigen genes of PorA, factor H binding protein (fHbp), Neisserial Heparin Binding Antigen (NHBA), and Neisseria Adhesin A (NadA). RESULTS Of the 263 IMD isolates analysed, 229, 16, 10, 7, and 1 belonged to MenB, MenY, MenW, MenC, and MenX, respectively. Of the 229 MenB, 159 (69.4 %) were typed as ST-269 clonal complex (CC); and they possessed a restricted number of three fHbp and five nhba gene alleles. Nine N. meningitidis isolates (eight MenB and one MenY) were found to possess at least one gene that encoded for an antigen that matched exactly with protein variants in the 4CMenB vaccine. Two MenB expressed PorA antigen P1.4 and possessed the nhba gene for peptide 2; four other MenB were predicted to have NHBA peptide 2; another two MenB were predicted to encode fHbp peptide 1.1; and a single MenY was found to have nadA gene for NadA peptide 8. In addition, another 172 isolates were found to possess genes for variant 1 fHbp peptides other than peptide 1.1 or NadA variant 1-2/3 peptides other than peptide 8; and therefore, may potentially be covered by 4CMenB. CONCLUSION The most prevalent clone of N. meningitidis in Quebec was ST-269 CC; and 96 % of the isolates in this CC were predicted to be covered by 4CMenB vaccine. Extensive genetic diversity was found in the other IMD isolates in Québec which might suggest a lower coverage by the vaccine when compared to the ST-269 MenB.
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Affiliation(s)
- Dennis K S Law
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, R3E 3R2, Winnipeg, MB, Canada.
| | - Brigitte Lefebvre
- Laboratoire de santé publique du Québec, Institut national de santé publique du Québec, 20045 chemin Sante-Marie, Ste-Anne-de-Bellevue, H9X 3R5, Québec, Canada.
| | - Rodica Gilca
- Institut national de santé publique du Québec, Centre de Recherche du CHUL-CHUQ, Québec, Canada.
- Département de Médecine Sociale et Préventive de I'Université Laval, Québec, Canada.
| | - Saul Deng
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, R3E 3R2, Winnipeg, MB, Canada.
| | - Jianwei Zhou
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, R3E 3R2, Winnipeg, MB, Canada.
| | - Philippe De Wals
- Institut national de santé publique du Québec, Centre de Recherche du CHUL-CHUQ, Québec, Canada.
- Département de Médecine Sociale et Préventive de I'Université Laval, Québec, Canada.
| | - Raymond S W Tsang
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, R3E 3R2, Winnipeg, MB, Canada.
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Rojas E, Hoyos J, Oldfield NJ, Lee P, Flint M, Jones CH, Ala’Aldeen DAA, Jansen KU, Anderson AS. Optimization of Molecular Approaches to Genogroup Neisseria meningitidis Carriage Isolates and Implications for Monitoring the Impact of New Serogroup B Vaccines. PLoS One 2015; 10:e0132140. [PMID: 26147212 PMCID: PMC4493136 DOI: 10.1371/journal.pone.0132140] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 06/10/2015] [Indexed: 01/14/2023] Open
Abstract
The reservoir for Neisseria meningitidis (Nm) is the human oropharynx. Implementation of Nm serogroup C (NmC) glycoconjugate vaccines directly reduced NmC carriage. Prophylactic vaccines are now available to prevent disease caused by the five major Nm disease causing serogroups (ABCWY). Nm serogroup B (NmB) vaccines are composed of antigens that are conserved across Nm serogroups and therefore have the potential to impact all Nm carriage. To assess the effect of these vaccines on carriage, standardized approaches to identify and group Nm are required. Real-time PCR (rt-PCR) capsule grouping assays that were internally controlled to confirm Nm species were developed for eight serogroups associated with carriage (A, B, C, E, W, X, Y and Z). The grouping scheme was validated using diverse bacterial species associated with carriage and then used to evaluate a collection of diverse Nm carriage isolates (n=234). A scheme that also included porA and ctrA probes was able to speciate the isolates, while ctrA also provided insights on the integrity of the polysaccharide loci. Isolates were typed for the Nm vaccine antigen factor H binding protein (fHbp), and were found to represent the known diversity of this antigen. The porA rt-PCR yielded positive results with all 234 of the Nm carriage isolates. Genogrouping assays classified 76.5% (179/234) of these isolates to a group, categorized 53 as nongenogroupable (NGG) and two as mixed results. Thirty seven NGG isolates evidenced a disrupted capsular polysaccharide operon judged by a ctrA negative result. Only 28.6% (67/234) of the isolates were serogrouped by slide agglutination (SASG), highlighting the reduced capability of carriage strains to express capsular polysaccharide. These rt-PCR assays provide a comprehensive means to identify and genogroup N. meningitidis in carriage studies used to guide vaccination strategies and to assess the impact of novel fHbp containing vaccines on meningococcal carriage.
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Affiliation(s)
- Eduardo Rojas
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | - Johanna Hoyos
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | - Neil J. Oldfield
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Philip Lee
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | - Mike Flint
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | - C. Hal Jones
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | | | - Kathrin U. Jansen
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
| | - Annaliesa S. Anderson
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, United States of America
- * E-mail:
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117
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Zaheer R, Klima CL, McAllister TA. Expeditious screening of candidate proteins for microbial vaccines. J Microbiol Methods 2015; 116:53-9. [PMID: 26149626 DOI: 10.1016/j.mimet.2015.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 06/26/2015] [Accepted: 06/27/2015] [Indexed: 11/18/2022]
Abstract
Advancements in high-throughput "omics" technologies have revolutionized the way vaccine candidates are identified. Now every surface expressed protein that an organism produces can be identified in silico and possibly made available for the rapid development of recombinant/subunit vaccines. However, evaluating the antigenicity of a large number of candidate proteins is an immense challenge, typically requiring cloning of several hundred candidates followed by immunogenicity screening. Here we report the development of a rapid, high-throughput method for screening candidate proteins for vaccines. This method involves utilizing a coupled, cell-free transcription-translation system to screen tagged proteins that are captured at the C-termini using appropriate ligand coated wells in 96 well ELISA plates. The template DNA for the cell-free expression is generated by two sequential PCRs and includes gene coding sequences, promoter, terminator, other necessary cis-acting elements and appropriate tag sequences. The process generates expressible candidate proteins containing two different peptide tags at the N- and the C-termini of the protein molecules. Proteins are screened in parallel for their quantity and immunoreactivity with N-terminal tag antibodies and antisera raised against the pathogen of interest, respectively. Normalization against the total detectable bound protein in the control wells allows for the identification of highly immunoreactive candidates. For this study we selected 30 representatives of >300 potential candidate proteins from Mannheimia haemolytica, a bacterial agent of pneumonia in feedlot cattle for expression with N-terminal Strep-II and C-terminal His(x6)-tag and evaluated their relative immunoreactivities using Strep-tactin-HRP and rabbit antisera generated against M. haemolytica. Using this system we were able to swiftly and quantitatively analyze and rank the suitability of proteins to identify potentially viable vaccine candidates, with the majority of the high ranking candidates being associated with virulence and pathogenicity. The system is adaptable to any bacterial target and presents an alternative to conventional laborious cloning, expression and screening procedures.
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Affiliation(s)
- Rahat Zaheer
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada
| | - Cassidy L Klima
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada
| | - Tim A McAllister
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1 Canada.
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Abstract
Two licensed serogroup B meningococcal vaccines contain factor H binding protein (FHbp). The antigen specifically binds human FH, which downregulates complement. In wild-type mice whose mouse FH does not bind to FHbp vaccines, the serum anti-FHbp antibody response inhibited binding of human FH to FHbp. The inhibition was important for eliciting broad anti-FHbp serum bactericidal activity. In human FH transgenic mice and some nonhuman primates, FHbp was able to form a complex with FH and FHbp vaccination elicited anti-FHbp antibodies that did not inhibit FH binding. To investigate the human anti-FHbp repertoire, we cloned immunoglobulin heavy- and light-chain-variable-region genes of individual B cells from three adults immunized with FHbp vaccines and generated 10 sequence-distinct native anti-FHbp antibody fragments (Fabs). All 10 Fabs bound to live meningococci; only 1 slightly inhibited binding of human FH, while 4 enhanced FH binding. Affinity-purified anti-FHbp antibody from serum of a fourth immunized adult also enhanced binding of human FH to live meningococcal bacteria. Despite the bound FH, the affinity-purified serum anti-FHbp antibodies elicited human complement-mediated bactericidal activity that was amplified by the alternative pathway. The lack of FH inhibition by the human anti-FHbp Fabs and serum antibodies suggests that binding of human FH to the vaccine antigen skews the anti-FHbp antibody repertoire to epitopes outside the FH-binding site. Mutant FHbp vaccines with decreased FH binding may represent a means to redirect the human antibody repertoire to epitopes within the FH binding site, which can inhibit FH binding and, potentially, increase safety and protective activity. Two meningococcal vaccines contain factor H binding protein (FHbp). Immunized mice whose mouse factor H (FH) does not bind to FHbp develop serum anti-FHbp antibodies that block binding of human FH to the bacteria. With less bound FH, the bacteria become more susceptible to complement killing. To investigate human responses, we isolated 10 recombinant anti-FHbp antibody fragments (Fabs) from immune cells of three immunized adults. One slightly inhibited binding of FH to the bacteria, and four enhanced FH binding. Purified serum anti-FHbp antibodies from a fourth immunized adult also enhanced FH binding. Although bound FH would be expected to block the alternative pathway, the human anti-FHbp antibodies retained bactericidal activity and the ability to activate the alternative pathway. Mutant FHbp vaccines with decreased binding to human FH may redirect the human antibody repertoire to epitopes within the FH binding site that inhibit FH binding, which are expected to increase protective activity.
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119
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A Mutant Library Approach to Identify Improved Meningococcal Factor H Binding Protein Vaccine Antigens. PLoS One 2015; 10:e0128185. [PMID: 26057742 PMCID: PMC4461315 DOI: 10.1371/journal.pone.0128185] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 04/23/2015] [Indexed: 01/14/2023] Open
Abstract
Factor H binding protein (FHbp) is a virulence factor used by meningococci to evade the host complement system. FHbp elicits bactericidal antibodies in humans and is part of two recently licensed vaccines. Using human complement Factor H (FH) transgenic mice, we previously showed that binding of FH decreased the protective antibody responses to FHbp vaccination. Therefore, in the present study we devised a library-based method to identify mutant FHbp antigens with very low binding of FH. Using an FHbp sequence variant in one of the two licensed vaccines, we displayed an error-prone PCR mutant FHbp library on the surface of Escherichia coli. We used fluorescence-activated cell sorting to isolate FHbp mutants with very low binding of human FH and preserved binding of control anti-FHbp monoclonal antibodies. We sequenced the gene encoding FHbp from selected clones and introduced the mutations into a soluble FHbp construct. Using this approach, we identified several new mutant FHbp vaccine antigens that had very low binding of FH as measured by ELISA and surface plasmon resonance. The new mutant FHbp antigens elicited protective antibody responses in human FH transgenic mice that were up to 20-fold higher than those elicited by the wild-type FHbp antigen. This approach offers the potential to discover mutant antigens that might not be predictable even with protein structural information and potentially can be applied to other microbial vaccine antigens that bind host proteins.
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120
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Molecular Engineering of Ghfp, the Gonococcal Orthologue of Neisseria meningitidis Factor H Binding Protein. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:769-77. [PMID: 25947148 DOI: 10.1128/cvi.00794-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 04/28/2015] [Indexed: 11/20/2022]
Abstract
Knowledge of the sequences and structures of proteins produced by microbial pathogens is continuously increasing. Besides offering the possibility of unraveling the mechanisms of pathogenesis at the molecular level, structural information provides new tools for vaccine development, such as the opportunity to improve viral and bacterial vaccine candidates by rational design. Structure-based rational design of antigens can optimize the epitope repertoire in terms of accessibility, stability, and variability. In the present study, we used epitope mapping information on the well-characterized antigen of Neisseria meningitidis factor H binding protein (fHbp) to engineer its gonococcal homologue, Ghfp. Meningococcal fHbp is typically classified in three distinct antigenic variants. We introduced epitopes of fHbp variant 1 onto the surface of Ghfp, which is naturally able to protect against meningococcal strains expressing fHbp of variants 2 and 3. Heterologous epitopes were successfully transplanted, as engineered Ghfp induced functional antibodies against all three fHbp variants. These results confirm that structural vaccinology represents a successful strategy for modulating immune responses, and it is a powerful tool for investigating the extension and localization of immunodominant epitopes.
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121
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Bradley DT, Bourke TW, Fairley DJ, Borrow R, Shields MD, Zipfel PF, Hughes AE. Susceptibility to invasive meningococcal disease: polymorphism of complement system genes and Neisseria meningitidis factor H binding protein. PLoS One 2015; 10:e0120757. [PMID: 25798599 PMCID: PMC4370764 DOI: 10.1371/journal.pone.0120757] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/05/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Neisseria meningitidis can cause severe infection in humans. Polymorphism of Complement Factor H (CFH) is associated with altered risk of invasive meningococcal disease (IMD). We aimed to find whether polymorphism of other complement genes altered risk and whether variation of N. meningitidis factor H binding protein (fHBP) affected the risk association. METHODS We undertook a case-control study with 309 European cases and 5,200 1958 Birth Cohort and National Blood Service cohort controls. We used additive model logistic regression, accepting P<0.05 as significant after correction for multiple testing. The effects of fHBP subfamily on the age at infection and severity of disease was tested using the independent samples median test and Student's T test. The effect of CFH polymorphism on the N. meningitidis fHBP subfamily was investigated by logistic regression and Chi squared test. RESULTS Rs12085435 A in C8B was associated with odds ratio (OR) of IMD (0.35 [95% CI 0.19-0.67]; P = 0.03 after correction). A CFH haplotype tagged by rs3753396 G was associated with IMD (OR 0.56 [95% CI 0.42-0.76], P = 1.6x10⁻⁴). There was no bacterial load (CtrA cycle threshold) difference associated with carriage of this haplotype. Host CFH haplotype and meningococcal fHBP subfamily were not associated. Individuals infected with meningococci expressing subfamily A fHBP were younger than those with subfamily B fHBP meningococci (median 1 vs 2 years; P = 0.025). DISCUSSION The protective CFH haplotype alters odds of IMD without affecting bacterial load for affected heterozygotes. CFH haplotype did not affect the likelihood of infecting meningococci having either fHBP subfamily. The association between C8B rs12085435 and IMD requires independent replication. The CFH association is of interest because it is independent of known functional polymorphisms in CFH. As fHBP-containing vaccines are now in use, relationships between CFH polymorphism and vaccine effectiveness and side-effects may become important.
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Affiliation(s)
- Declan T. Bradley
- Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast, United Kingdom
- Public Health Agency, Belfast, United Kingdom
- * E-mail:
| | - Thomas W. Bourke
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast, United Kingdom
| | - Derek J. Fairley
- Regional Virus Laboratory, Belfast Health and Social Care Trust, Belfast, United Kingdom
| | - Raymond Borrow
- Vaccine Evaluation Unit, Public Health England, Manchester, United Kingdom
- Inflammation Sciences Research Group, School of Translational Medicine, University of Manchester, Manchester, United Kingdom
| | - Michael D. Shields
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast, United Kingdom
| | - Peter F. Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology—Hans Knöll Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | - Anne E. Hughes
- Formerly of Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast, United Kingdom
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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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123
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Brendish NJ, Read RC. Neisseria meningitidisserogroup B bivalent factor H binding protein vaccine. Expert Rev Vaccines 2015; 14:493-503. [DOI: 10.1586/14760584.2015.1015997] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Granoff DM, Costa I, Konar M, Giuntini S, Van Rompay KKA, Beernink PT. Binding of Complement Factor H (FH) Decreases Protective Anti-FH Binding Protein Antibody Responses of Infant Rhesus Macaques Immunized With a Meningococcal Serogroup B Vaccine. J Infect Dis 2015; 212:784-92. [PMID: 25676468 DOI: 10.1093/infdis/jiv081] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/05/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The meningococcal vaccine antigen, factor H (FH)-binding protein (FHbp), binds human complement FH. In human FH transgenic mice, binding decreased protective antibody responses. METHODS To investigate the effect of primate FH binding, we immunized rhesus macaques with a 4-component serogroup B vaccine (4CMenB). Serum FH in 6 animals bound strongly to FHbp (FHbp-FH(high)) and, in 6 animals, bound weakly to FHbp (FHbp-FH(low)). RESULTS There were no significant differences between the respective serum bactericidal responses of the 2 groups against meningococcal strains susceptible to antibody to the NadA or PorA vaccine antigens. In contrast, anti-FHbp bactericidal titers were 2-fold lower in FHbp-FH(high) macaques against a strain with an exact FHbp match to the vaccine (P = .08) and were ≥4-fold lower against 4 mutants with other FHbp sequence variants (P ≤ .005, compared with FHbp-FH(low) macaques). Unexpectedly, postimmunization sera from all 12 macaques enhanced FH binding to meningococci. In contrast, serum anti-FHbp antibodies elicited by 4CMenB in mice whose mouse FH did not bind to the vaccine antigen inhibited FH binding. CONCLUSIONS Binding of FH to FHbp decreases protective anti-FHbp antibody responses of macaques to 4CMenB. Even low levels of FH binding skew the antibody repertoire to FHbp epitopes outside of the FH-binding site, which enhance FH binding.
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Affiliation(s)
- Dan M Granoff
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute
| | - Isabella Costa
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute
| | - Monica Konar
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute
| | - Serena Giuntini
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute
| | - Koen K A Van Rompay
- California National Primate Research Center, University of California-Davis, California
| | - Peter T Beernink
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute
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A native outer membrane vesicle vaccine confers protection against meningococcal colonization in human CEACAM1 transgenic mice. Vaccine 2015; 33:1317-1323. [PMID: 25662856 DOI: 10.1016/j.vaccine.2015.01.057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 12/30/2014] [Accepted: 01/22/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND The effect of protein-based meningococcal vaccines on prevention of nasopharyngeal colonization has been difficult to investigate experimentally because a reliable animal colonization model did not exist. METHODS Human CEACAM1 transgenic mice, which can be colonized by meningococci, were immunized IP with one of two meningococcal native outer membrane vesicle (NOMV) vaccines prepared from mutants with attenuated endotoxin (lpxL1 knockout) and over-expressed sub-family B Factor H-binding proteins (FHbp). Animals were challenged intranasally two weeks after the third dose with wild-type strain H44/76, or were treated IP with anti-NOMV serum before and during the bacterial challenge. RESULTS The NOMV-1 vaccine, prepared from the serogroup B H44/76 mutant, elicited ∼40-fold higher serum bactericidal antibody titers against the wild-type H44/76 challenge strain than the NOMV-2 vaccine prepared from a heterologous serogroup W mutant strain with different PorA and FHbp amino acid sequence variants. Compared to aluminum hydroxide-immunized control mice, the efficacy for prevention of any H44/76 colonization was 93% (95% confidence interval, 52-99, P<0.0001) for the NOMV-1 vaccine, and 19% (-3-36, P=0.23) for NOMV-2. NOMV-2-vaccinated mice had a 5.6-fold decrease in geometric mean CFU of bacteria per animal in tracheal washes compared to control mice (P=0.007). The efficacy of passive administration of serum from NOMV-1-vaccinated mice to immunologically naïve mice against colonization was 44% (17-61; P=0.002). CONCLUSIONS Both NOMV vaccines protected against meningococcal colonization but there was greater protection by the NOMV-1 vaccine with antigens matched with the challenge strain. Meningococcal vaccines that target protein antigens have potential to decrease colonization.
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Binding of complement factor H to PorB3 and NspA enhances resistance of Neisseria meningitidis to anti-factor H binding protein bactericidal activity. Infect Immun 2015; 83:1536-45. [PMID: 25644002 DOI: 10.1128/iai.02984-14] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Among 25 serogroup B Neisseria meningitidis clinical isolates, we identified four (16%) with high factor H binding protein (FHbp) expression that were resistant to complement-mediated bactericidal activity of sera from mice immunized with recombinant FHbp vaccines. Two of the four isolates had evidence of human FH-dependent complement downregulation independent of FHbp. Since alternative complement pathway recruitment is critical for anti-FHbp bactericidal activity, we hypothesized that in these two isolates binding of FH to ligands other than FHbp contributes to anti-FHbp bactericidal resistance. Knocking out NspA, a known meningococcal FH ligand, converted both resistant isolates to anti-FHbp susceptible isolates. The addition of a nonbactericidal anti-NspA monoclonal antibody to the bactericidal reaction also increased anti-FHbp bactericidal activity. To identify a role for FH ligands other than NspA or FHbp in resistance, we created double NspA/FHbp knockout mutants. Mutants from both resistant isolates bound 10-fold more recombinant human FH domains 6 and 7 fused to Fc than double knockout mutants prepared from two sensitive meningococcal isolates. In light of recent studies showing functional FH-PorB2 interactions, we hypothesized that PorB3 from the resistant isolates recruited FH. Allelic exchange of porB3 from a resistant isolate to a sensitive isolate increased resistance of the sensitive isolate to anti-FHbp bactericidal activity (and vice versa). Thus, some PorB3 variants functionally bind human FH, which in the presence of NspA enhances anti-FHbp resistance. Combining anti-NspA antibodies with anti-FHbp antibodies can overcome resistance. Meningococcal vaccines that target both NspA and FHbp are likely to confer greater protection than either antigen alone.
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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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128
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Pizza M, Rappuoli R. Neisseria meningitidis: pathogenesis and immunity. Curr Opin Microbiol 2014; 23:68-72. [PMID: 25461575 DOI: 10.1016/j.mib.2014.11.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/08/2014] [Accepted: 11/10/2014] [Indexed: 12/20/2022]
Abstract
The recent advances in cellular microbiology, genomics, and immunology has opened new horizons in the understanding of meningococcal pathogenesis and in the definition of new prophylactic intervention. It is now clear that Neissera meningitidis has evolved a number of surface structures to mediate interaction with host cells and a number of mechanisms to subvert the immune system and escape complement-mediated killing. In this review we report the more recent findings on meningococcal adhesion and on the bacteria-complement interaction highlighting the redundancy of these mechanisms. An effective vaccine against meningococcus B, based on multiple antigens with different function, has been recently licensed. The antibodies induced by the 4CMenB vaccine could mediate bacterial killing by activating directly the classical complement pathway or, indirectly, by preventing binding of fH on the bacterial surface and interfering with colonization.
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129
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Zlotnick GW, Jones TR, Liberator P, Hao L, Harris S, McNeil LK, Zhu D, Perez J, Eiden J, Jansen KU, Anderson AS. The discovery and development of a novel vaccine to protect against Neisseria meningitidis Serogroup B Disease. Hum Vaccin Immunother 2014; 11:5-13. [PMID: 25483509 DOI: 10.4161/hv.34293] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Vaccines have had a major impact on the reduction of many diseases globally. Vaccines targeted against invasive meningococcal disease (IMD) due to serogroups A, C, W, and Y are used to prevent these diseases. Until recently no vaccine had been identified that could confer broad protection against Neisseria meningitidis serogroup B (MnB). MnB causes IMD in the very young, adolescents and young adults and thus represents a significant unmet medical need. In this brief review, we describe the discovery and development of a vaccine that has the potential for broad protection against this devastating disease.
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130
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Heterogeneity in rhesus macaque complement factor H binding to meningococcal factor H binding protein (FHbp) informs selection of primates to assess immunogenicity of FHbp-based vaccines. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:1505-11. [PMID: 25185576 DOI: 10.1128/cvi.00517-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neisseria meningitidis causes disease only in humans. An important mechanism underlying this host specificity is the ability of the organism to resist complement by recruiting the complement downregulator factor H (FH) to the bacterial surface. In previous studies, binding of FH to one of the major meningococcal FH ligands, factor H binding protein (FHbp), was reported to be specific for human FH. Here we report that sera from 23 of 73 rhesus macaques (32%) tested had high FH binding to FHbp. Similar to human FH, binding of macaque FH to the meningococcal cell surface inhibited the complement alternative pathway by decreasing deposition of C3b. FH contains 20 domains (or short consensus repeats), with domains 6 and 7 being responsible for binding of human FH to FHbp. DNA sequence analyses of FH domains 6 and 7 from macaques with high or low FH binding showed a polymorphism at residue 352 in domain 6, with Tyr being associated with high binding and His with low binding. A recombinant macaque FH 6,7/Fc fragment with Tyr352 showed higher binding to FHbp than the corresponding fragment with His352. In previous studies in human FH transgenic mice, binding of FH to FHbp vaccines decreased protective antibody responses, and mutant FHbp vaccines with decreased FH binding elicited serum antibodies with greater protective activity. Thus, macaques with high FH binding to FHbp represent an attractive nonhuman primate model to investigate further the effects of FH binding on the immunogenicity of FHbp vaccines.
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131
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A randomized, phase 1/2 trial of the safety, tolerability, and immunogenicity of bivalent rLP2086 meningococcal B vaccine in healthy infants. Vaccine 2014; 32:5206-11. [DOI: 10.1016/j.vaccine.2014.07.049] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/03/2014] [Accepted: 07/15/2014] [Indexed: 11/22/2022]
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132
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Human factor H (FH) impairs protective meningococcal anti-FHbp antibody responses and the antibodies enhance FH binding. mBio 2014; 5:e01625-14. [PMID: 25161192 PMCID: PMC4173785 DOI: 10.1128/mbio.01625-14] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED The meningococcal 4CMenB vaccine (Bexsero; Novartis) contains four antigens that can elicit serum bactericidal activity, one of which is factor H (FH)-binding protein (FHbp). FHbp specifically binds human complement FH. When humans are immunized, FHbp is expected to form a complex with FH, which could affect immunogenicity and safety. Wild-type mice (whose FH does not bind to FHbp) and human FH transgenic mice were immunized with three doses of 4CMenB, and their responses were compared. There were no significant differences between the serum bactericidal responses of transgenic and wild-type mice to strains with all of the antigens mismatched for 4CMenB except PorA or NadA. In contrast, against a strain mismatched for all of the antigens except FHbp, the transgenic mice had 15-fold weaker serum bactericidal antibody responses (P = 0.0006). Binding of FH downregulates complement. One explanation for the lower anti-FHbp serum bactericidal activity in the transgenic mice is that their postimmunization serum samples enhanced the binding of FH to FHbp, whereas the serum samples from the wild-type mice inhibited FH binding. Control antiserum from transgenic mice immunized with a low-FH-binding mutant FHbp (R41S) vaccine inhibited FH binding. Two 4CMenB-vaccinated transgenic mice developed serum IgM autoantibodies to human FH. Thus, human FH impairs protective serum anti-FHbp antibody responses, in part by skewing the antibody repertoire to FHbp epitopes outside the FH binding site. FHbp vaccines that bind FH may elicit FH autoantibodies. Mutant FHbp antigens with low FH binding could improve protection and, potentially, vaccine safety in humans. IMPORTANCE Two serogroup B meningococcal vaccines contain a novel antigen called factor H (FH)-binding protein (FHbp). FHbp specifically binds human FH, a plasma protein that downregulates complement. One vaccine (4CMenB; Novartis) is licensed in Europe, Canada, and Australia. When humans are immunized, FHbp can complex with FH. We compared the immunogenicity of 4CMenB vaccine in wild-type mice, whose own FH does not bind to FHbp, and human FH transgenic mice. Transgenic mice had respective antibody responses similar to those of wild-type mice to 4CMenB antigens that do not bind FH. However, the protective antibody responses of the transgenic mice to FHbp were impaired, largely because the antibodies did not inhibit but rather enhanced the binding of FH to FHbp. Two transgenic mice developed serum IgM autoantibodies to FH. Mutant FHbp antigens with low FH binding likely will elicit greater protection in humans than FHbp vaccines that bind FH and have a lower risk of FH autoantibodies.
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133
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Agarwal S, Vasudhev S, DeOliveira RB, Ram S. Inhibition of the classical pathway of complement by meningococcal capsular polysaccharides. THE JOURNAL OF IMMUNOLOGY 2014; 193:1855-63. [PMID: 25015832 DOI: 10.4049/jimmunol.1303177] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Almost all invasive Neisseria meningitidis isolates express capsular polysaccharide. Ab is required for complement-dependent killing of meningococci. Although alternative pathway evasion has received considerable attention, little is known about classical pathway (CP) inhibition by meningococci, which forms the basis of this study. We engineered capsulated and unencapsulated isogenic mutant strains of groups A, B, C, W, and Y meningococci to express similar amounts of the same factor H-binding protein (fHbp; a key component of group B meningococcal vaccines) molecule. Despite similar anti-fHbp mAb binding, significantly less C4b was deposited on all five encapsulated mutants compared with their unencapsulated counterparts (p < 0.01) when purified C1 and C4 were used to deposit C4b. Reduced C4b deposition was the result of capsule-mediated inhibition of C1q engagement by Ab. C4b deposition correlated linearly with C1q engagement by anti-fHbp. Whereas B, C, W, and Y capsules limited CP-mediated killing by anti-fHbp, the unencapsulated group A mutant paradoxically was more resistant than its encapsulated counterpart. Strains varied considerably in their susceptibility to anti-fHbp and complement despite similar Ab binding, which may have implications for the activity of fHbp-based vaccines. Capsule also limited C4b deposition by anti-porin A mAbs. Capsule expression decreased binding of an anti-lipooligosaccharide IgM mAb (∼ 1.2- to 2-fold reduction in fluorescence). Akin to observations with IgG, capsule also decreased IgM-mediated C4b deposition when IgM binding to the mutant strain pairs was normalized. In conclusion, we show that capsular polysaccharide, a critical meningococcal virulence factor, inhibits the CP of complement.
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Affiliation(s)
- Sarika Agarwal
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester MA 01605
| | - Shreekant Vasudhev
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester MA 01605
| | - Rosane B DeOliveira
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester MA 01605
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester MA 01605
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134
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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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135
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Pan X, Yang Y, Zhang JR. Molecular basis of host specificity in human pathogenic bacteria. Emerg Microbes Infect 2014; 3:e23. [PMID: 26038515 PMCID: PMC3974339 DOI: 10.1038/emi.2014.23] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 01/15/2014] [Accepted: 01/19/2014] [Indexed: 01/08/2023]
Abstract
Pathogenic bacteria display various levels of host specificity or tropism. While many bacteria can infect a wide range of hosts, certain bacteria have strict host selectivity for humans as obligate human pathogens. Understanding the genetic and molecular basis of host specificity in pathogenic bacteria is important for understanding pathogenic mechanisms, developing better animal models and designing new strategies and therapeutics for the control of microbial diseases. The molecular mechanisms of bacterial host specificity are much less understood than those of viral pathogens, in part due to the complexity of the molecular composition and cellular structure of bacterial cells. However, important progress has been made in identifying and characterizing molecular determinants of bacterial host specificity in the last two decades. It is now clear that the host specificity of bacterial pathogens is determined by multiple molecular interactions between the pathogens and their hosts. Furthermore, certain basic principles regarding the host specificity of bacterial pathogens have emerged from the existing literature. This review focuses on selected human pathogenic bacteria and our current understanding of their host specificity.
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Affiliation(s)
- Xiaolei Pan
- Center for Infectious Disease Research, School of Medicine, Tsinghua University , Beijing 10084, China
| | - Yang Yang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University , Beijing 10084, China
| | - Jing-Ren Zhang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University , Beijing 10084, China
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136
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Holst J, Comanducci M, Bambini S, Muzzi A, Comandi S, Oksnes J, DeTora L, Pizza M, Rappuoli R, Caugant DA. Variability of genes encoding surface proteins used as vaccine antigens in meningococcal endemic and epidemic strain panels from Norway. Vaccine 2014; 32:2722-31. [PMID: 24631075 DOI: 10.1016/j.vaccine.2014.02.068] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 02/05/2014] [Accepted: 02/25/2014] [Indexed: 01/10/2023]
Abstract
Surface-expressed protein antigens such as factor H-binding protein (fHbp), Neisserial adhesin A (NadA), Neisserial heparin-binding antigen (NHBA) and Porin protein A (PorA); all express sequence variability that can affect their function as protective immunogens when used in meningococcal serogroup B vaccines like the recently-approved 4CMenB (Bexsero(®)). We assessed the sequence variation of genes coding for these proteins and two additional proteins ("fusion partners" to fHbp and NHBA) in pathogenic isolates from a recent low incidence period (endemic situation; 2005-2006) in Norway. Findings among strains from this panel were contrasted to what was found among isolates from a historic outbreak (epidemic situation; 1985-1990). Multilocus sequence typing revealed 14 clonal complexes (cc) among the 66 endemic strains, while cc32 vastly predominated in the 38-strain epidemic panel. Serogroup B isolates accounted for 50/66 among endemic strains and 28/38 among epidemic strains. Potential strain-coverage ("sequence match") for the 4CMenB vaccine was identified among the majority (>70%) of the endemic serogroup B isolates and all of the epidemic serogroup B isolates evaluated. Further information about the degree of expression, surface availability and the true cross-reactivity for the vaccine antigens will be needed to fully characterize the clinical strain-coverage of 4CMenB in various geographic and epidemiological situations.
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Affiliation(s)
- Johan Holst
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway.
| | | | | | | | - Sara Comandi
- Novartis Vaccines and Diagnostics, Siena, Italy.
| | - Jan Oksnes
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway
| | - Lisa DeTora
- Novartis Vaccines and Diagnostics, Cambridge, USA.
| | | | | | - Dominique A Caugant
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway; Section for International Health, Faculty of Medicine, University of Oslo, Oslo, Norway
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137
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Williams JN, Weynants V, Poolman JT, Heckels JE, Christodoulides M. Immuno-proteomic analysis of human immune responses to experimental Neisseria meningitidis outer membrane vesicle vaccines identifies potential cross-reactive antigens. Vaccine 2014; 32:1280-6. [DOI: 10.1016/j.vaccine.2013.12.070] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 11/25/2013] [Accepted: 12/19/2013] [Indexed: 11/26/2022]
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138
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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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139
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Gasparini R, Amicizia D, Domnich A, Lai PL, Panatto D. Neisseria meningitidis B vaccines: recent advances and possible immunization policies. Expert Rev Vaccines 2014; 13:345-64. [PMID: 24476428 DOI: 10.1586/14760584.2014.880341] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Since the development of the first-generation vaccines based on outer membrane vesicles (OMV), which were able to contain strain-specific epidemics, but were not suitable for universal use, enormous steps forward in the prevention of Neisseria meningitidis B have been made. The first multicomponent vaccine, Bexsero(®), has recently been authorized for use; other vaccines, bivalent rLP2086 and next-generation OMV vaccines, are under development. The new vaccines may substantially contribute to reducing invasive bacterial infections as they could cover most Neisseria meningitidis B strains. Moreover, other potentially effective serogroup B vaccine candidates are being studied in preclinical settings. It is therefore appropriate to review what has recently been achieved in the prevention of disease caused by serogroup B.
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140
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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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141
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Bai X, Borrow R. Genetic shifts ofNeisseria meningitidisserogroup B antigens and the quest for a broadly cross-protective vaccine. Expert Rev Vaccines 2014; 9:1203-17. [DOI: 10.1586/erv.10.116] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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142
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Anderson AS, Jansen KU, Eiden J. New frontiers in meningococcal vaccines. Expert Rev Vaccines 2014; 10:617-34. [DOI: 10.1586/erv.11.50] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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143
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Martin NG, Snape MD. A multicomponent serogroup B meningococcal vaccine is licensed for use in Europe: what do we know, and what are we yet to learn? Expert Rev Vaccines 2014; 12:837-58. [DOI: 10.1586/14760584.2013.814862] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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144
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Gorringe AR. CanNeisseria lactamicaantigens provide an effective vaccine to prevent meningococcal disease? Expert Rev Vaccines 2014; 4:373-9. [PMID: 16026250 DOI: 10.1586/14760584.4.3.373] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Neisseria lactamica is a commensal organism that is closely related to Neisseria meningitidis, the causative agent of meningococcal disease. N. lactamica has many antigens in common with N. meningitidis, but it lacks a polysaccharide capsule and the serosubtyping antigen PorA. Carriage studies have demonstrated that N. lactamica is carried in the nasopharynx of young children at a time when meningococcal carriage is rare. However, natural immunity to meningococcal disease develops during this period and carriage of commensal Neisseria is implicated in the development of this immunity. Recent studies have characterized the antigens which may be responsible for inducing a crossreactive antibody response and have demonstrated that N. lactamica-based vaccines can protect in experimental models of meningococcal disease. The potential for these vaccines to be effective in preventing meningococcal disease is discussed.
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Affiliation(s)
- Andrew R Gorringe
- Centre for Emergency Preparedness and Response, Health Protection Agency, Porton Down, Salisbury, SP4 0JG, UK.
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145
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Advances towards the prevention of meningococcal B disease: A multidimensional story. J Infect 2014; 68 Suppl 1:S76-82. [DOI: 10.1016/j.jinf.2013.09.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2013] [Indexed: 11/18/2022]
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146
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Nonfunctional variant 3 factor H binding proteins as meningococcal vaccine candidates. Infect Immun 2013; 82:1157-63. [PMID: 24379280 DOI: 10.1128/iai.01183-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neisseria meningitidis is a human-specific pathogen and leading cause of meningitis and septicemia. Factor H binding protein (fHbp), a virulence factor which protects N. meningitidis from innate immunity by binding the human complement regulator factor H (fH) with high affinity, is also a key antigen in vaccines being developed to prevent meningococcal disease. fHbp can be divided into three variant groups (V1, V2, and V3) that elicit limited immunological cross-reactivity. The interaction of fH with fHbp could impair the immunogenicity of this antigen by hindering access to the antigenic epitopes in fHbp, providing the rationale for the development of nonfunctional fHbps as vaccine candidates. Here, we characterized the two nonfunctional V3 fHbps, fHbp(T286A) and fHbp(E313A), which each contains a single amino acid substitution that leads to a marked reduction in affinity for fH without affecting the folding of the proteins. The immunogenicity of the nonfunctional fHbps was assessed in transgenic mice expressing a single chimeric fH containing domains of human fH involved in binding to fHbp. No differences in anti-V3 fHbp antibody titers were elicited by the wild-type V3 fHbp, V3 fHbp(T286A), and V3 fHbp(E313A), demonstrating that the nonfunctional fHbps retain their immunogenicity. Furthermore, the nonfunctional V3 fHbps elicit serum bactericidal activity that is equivalent to or higher than that observed with the wild-type protein. Our findings provide the basis for the rational design of next-generation vaccines containing nonfunctional V3 fHbps.
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147
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Faleri A, Santini L, Brier S, Pansegrau W, Lo Surdo P, Scarselli M, Buricchi F, Volpini G, Genovese A, van der Veen S, Lea S, Tang CM, Savino S, Pizza M, Finco O, Norais N, Masignani V. Two cross-reactive monoclonal antibodies recognize overlapping epitopes on Neisseria meningitidis factor H binding protein but have different functional properties. FASEB J 2013; 28:1644-53. [PMID: 24371123 DOI: 10.1096/fj.13-239012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Factor H binding protein (fHbp) is one of the main antigens of the 4-component meningococcus B (4CMenB) multicomponent vaccine against disease caused by serogroup B Neisseria meningitidis (MenB). fHbp binds the complement down-regulating protein human factor H (hfH), thus resulting in immune evasion. fHbp exists in 3 variant groups with limited cross-protective responses. Previous studies have described the generation of monoclonal antibodies (mAbs) targeting variant-specific regions of fHbp. Here we report for the first time the functional characterization of two mAbs that recognize a wide panel of fHbp variants and subvariants on the MenB surface and that are able to inhibit fHbp binding to hfH. The antigenic regions targeted by the two mAbs were accurately mapped by hydrogen-deuterium exchange mass spectrometry (HDX-MS), revealing partially overlapping epitopes on the N terminus of fHbp. Furthermore, while none of the mAbs had bactericidal activity on its own, a synergistic effect was observed for each of them when tested by the human complement serum bactericidal activity (hSBA) assay in combination with a second nonbactericidal mAb. The bases underlying fHbp variant cross-reactivity, as well as inhibition of hfH binding and cooperativity effect observed for the two mAbs, are discussed in light of the mapped epitopes.
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Affiliation(s)
- Agnese Faleri
- 1Research Center, Novartis Vaccines and Diagnostics Srl, Via Fiorentina 1, 53100 Siena, Italy.
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Panatto D, Amicizia D, Lai PL, Cristina ML, Domnich A, Gasparini R. New versus old meningococcal group B vaccines: how the new ones may benefit infants & toddlers. Indian J Med Res 2013; 138:835-46. [PMID: 24521624 PMCID: PMC3978970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Invasive disease caused by Neisseria meningitidis is associated with high mortality and high disability rates and mainly affects children under one year of age. Vaccination is the best way to prevent meningococcal disease, especially in infants and toddlers. The introduction of massive meningococcal serogroup C vaccination has drastically reduced the incidence of disease caused by this serogroup, and serogroup B has now become the main causative agent in several industrialized countries. The first serogroup B vaccines, which were used for more than two decades, were based on outer membrane vesicles and proved to be protective only against specific epidemic strains in Cuba, Norway, Brazil and New Zealand. Moreover, these often elicited a scant immune response in young children. Innovative genomics-based reverse vaccinology subsequently enabled researchers to identify genes encoding for surface proteins that are able to elicit a strong immune response against several B strains. This important discovery led to the development and recent approval in Europe of the four-component meningococcal serogroup B (4CMenB) vaccine. Large clinical trials have shown high immunogenicity and tolerability and acceptable safety levels of 4CMenB in infants and toddlers. This vaccine is expected to cover a large number of circulating invasive strains and may also be efficacious against other serogroups. Young children are particularly vulnerable to the devastating consequences of meningococcal disease. Given the high performance of 4CMenB and its non-interference with routine vaccinations, this age-group will be the first to benefit from the introduction of this vaccine.
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Affiliation(s)
- D. Panatto
- Department of Health Sciences, University of Genoa, Genoa, Italy,Reprint requests: Dr D. Panatto, Department of Health Sciences, University of Genoa, via Pastore 1-16132, Genoa, Italy e-mail:
| | - D. Amicizia
- Department of Health Sciences, University of Genoa, Genoa, Italy
| | - PL. Lai
- Department of Health Sciences, University of Genoa, Genoa, Italy
| | - ML. Cristina
- Department of Health Sciences, University of Genoa, Genoa, Italy
| | - A. Domnich
- Department of Health Sciences, University of Genoa, Genoa, Italy
| | - R. Gasparini
- Department of Health Sciences, University of Genoa, Genoa, Italy
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149
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Newcombe J, Mendum TA, Ren CP, McFadden J. Identification of the immunoproteome of the meningococcus by cell surface immunoprecipitation and MS. MICROBIOLOGY-SGM 2013; 160:429-438. [PMID: 24275101 DOI: 10.1099/mic.0.071829-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Most healthy adults are protected from meningococcal disease by the presence of naturally acquired anti-meningococcal antibodies; however, the identity of the target antigens of this protective immunity remains unclear, particularly for protection against serogroup B disease. To identify the protein targets of natural protective immunity we developed an immunoprecipitation and proteomics approach to define the immunoproteome of the meningococcus. Sera from 10 healthy individuals showing serum bactericidal activity against both a meningococcal C strain (L91543) and the B strain MC58, together with commercially available pooled human sera, were used as probe antisera. Immunoprecipitation was performed with each serum sample and live cells from both meningococcal strains. Immunoprecipitated proteins were identified by MS. Analysis of the immunoproteome from each serum demonstrated both pan-reactive antigens that were recognized by most sera as well as subject-specific antigens. Most antigens were found in both meningococcal strains, but a few were strain-specific. Many of the immunoprecipitated proteins have been characterized previously as surface antigens, including adhesins and proteases, several of which have been recognized as vaccine candidate antigens, e.g. factor H-binding protein, NadA and neisserial heparin-binding antigen. The data demonstrate clearly the presence of meningococcal antibodies in healthy individuals with no history of meningococcal infection and a wide diversity of immune responses. The identification of the immunoreactive proteins of the meningococcus provides a basis for understanding the role of each antigen in the natural immunity associated with carriage and may help to design vaccination strategies.
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Affiliation(s)
- Jane Newcombe
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Tom A Mendum
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Chuan-Peng Ren
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Johnjoe McFadden
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK
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150
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Carter NJ. Multicomponent meningococcal serogroup B vaccine (4CMenB; Bexsero(®)): a review of its use in primary and booster vaccination. BioDrugs 2013; 27:263-74. [PMID: 23575646 DOI: 10.1007/s40259-013-0029-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Multicomponent meningococcal serogroup B vaccine (4CMenB; Bexsero(®)) is a unique vaccine containing four main immunogenic components: three recombinant proteins combined with outer membrane vesicles derived from meningococcal NZ98/254 strain. After three doses of 4CMenB (administered at 2, 3, and 4 months or 2, 4, and 6 months of age) in vaccine-naive infants, the majority of infants had seroprotective human complement serum bactericidal assay (hSBA) antibody titers against the meningococcal serogroup B test strains selected to be specific for the vaccine antigens in randomized, open-label or observer-blind, multicenter, phase IIb or III trials. In extensions to the phase III trial, two doses of 4CMenB administered between 12 and 15 months of age in vaccine-naive infants, and a single booster dose of 4CMenB administered at 12 months of age in vaccine-experienced infants, also elicited robust immunogenic responses. In a phase IIb/III trial, the majority of adolescents (aged 11-17 years) achieved seroprotective hSBA antibody titers against meningococcal serogroup B test strains after two doses of 4CMenB, and a third dose did not appear to add any extra protection. In adults who were potentially at an increased risk of occupational exposure to meningococcal isolates, seroprotection rates were high after one dose of 4CMenB and increased further after two or three doses in a small noncomparative, two-center, phase II trial. The reactogenicity of 4CMenB was generally acceptable in clinical trials. However, the vaccine was associated with more solicited systemic adverse events (particularly fever) in infants when coadministered with routine infant vaccines than when these vaccines were administered alone. In conclusion, 4CMenB effectively elicited immune responses against meningococcal serogroup B test strains selected to be specific for the vaccine antigens in infants, adolescents, and adults.
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Affiliation(s)
- Natalie J Carter
- Adis, 41 Centorian Drive, Private Bag 65901, Mairangi Bay, North Shore, 0754, Auckland, New Zealand.
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