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Bahadori S, Archambault MJ, Sebastiao M, Bourgault S, Giguère D. Convergent Synthesis of a Group B Streptococcus Type III Epitope Toward a Semisynthetic Carbohydrate-Based Vaccine. J Org Chem 2024; 89:13978-13992. [PMID: 39033407 DOI: 10.1021/acs.joc.4c01216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
In this work, we synthesized an hexasaccharide derived from the capsular polysaccharide of group B Streptococcus type III capsular polysaccharide. Our convergent 3 + 3 strategy avoided the use of benzyl protecting groups allowing the installation of an azide anchoring group and providing a high yield for the final deprotection steps. Moreover, the minimal hexasaccharidic epitope was conjugated to CRM197 and BSA via copper-catalyzed azide-alkyne cycloaddition for the preparation of a semisynthetic carbohydrate-based vaccine.
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Affiliation(s)
- Sam Bahadori
- Département de Chimie, Université Laval, 1045 Av. de la Médecine, Québec City, Quebec G1V 0A6, Canada
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Montreal, Quebec H2X 3Y7, Canada
| | - Marie-Jeanne Archambault
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Montreal, Quebec H2X 3Y7, Canada
- Department of Chemistry, Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada
| | - Mathew Sebastiao
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Montreal, Quebec H2X 3Y7, Canada
- Department of Chemistry, Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada
| | - Steve Bourgault
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Montreal, Quebec H2X 3Y7, Canada
- Department of Chemistry, Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada
| | - Denis Giguère
- Département de Chimie, Université Laval, 1045 Av. de la Médecine, Québec City, Quebec G1V 0A6, Canada
- Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Montreal, Quebec H2X 3Y7, Canada
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McBerney R, Dolan JP, Cawood EE, Webb ME, Turnbull WB. Bioorthogonal, Bifunctional Linker for Engineering Synthetic Glycoproteins. JACS AU 2022; 2:2038-2047. [PMID: 36186556 PMCID: PMC9516712 DOI: 10.1021/jacsau.2c00312] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 06/16/2023]
Abstract
Post-translational glycosylation of proteins results in complex mixtures of heterogeneous protein glycoforms. Glycoproteins have many potential applications from fundamental studies of glycobiology to potential therapeutics, but generating homogeneous recombinant glycoproteins using chemical or chemoenzymatic reactions to mimic natural glycoproteins or creating homogeneous synthetic neoglycoproteins is a challenging synthetic task. In this work, we use a site-specific bioorthogonal approach to produce synthetic homogeneous glycoproteins. We develop a bifunctional, bioorthogonal linker that combines oxime ligation and strain-promoted azide-alkyne cycloaddition chemistry to functionalize reducing sugars and glycan derivatives for attachment to proteins. We demonstrate the utility of this minimal length linker by producing neoglycoprotein inhibitors of cholera toxin in which derivatives of the disaccharide lactose and GM1os pentasaccharide are attached to a nonbinding variant of the cholera toxin B-subunit that acts as a size- and valency-matched multivalent scaffold. The resulting neoglycoproteins decorated with GM1 ligands inhibit cholera toxin B-subunit adhesion with a picomolar IC50.
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Abstract
The surface of the Gram-positive opportunistic pathogen Streptococcus agalactiae, or group B Streptococcus (GBS), harbors several carbohydrate and protein antigens with the potential to be effective vaccines. Capsular polysaccharides of all clinically-relevant GBS serotypes coupled to immunogenic proteins of both GBS and non-GBS origin have undergone extensive testing in animals that led to advanced clinical trials in healthy adult women. In addition, GBS proteins either alone or in combination have been tested in animals; a fusion protein construct has recently advanced to human clinical studies. Given our current understanding of the antigenicity and immunogenicity of the wide array of GBS surface antigens, formulations now exist for the generation of viable vaccines against diseases caused by GBS.
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Song JY, Lim JH, Lim S, Yong Z, Seo HS. Progress toward a group B streptococcal vaccine. Hum Vaccin Immunother 2018; 14:2669-2681. [PMID: 29995578 PMCID: PMC6314413 DOI: 10.1080/21645515.2018.1493326] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/18/2018] [Accepted: 06/19/2018] [Indexed: 01/31/2023] Open
Abstract
Streptococcus agalactiae (group B Streptococcus, GBS) is a leading cause of severe invasive disease in neonate, elderly, and immunocompromised patients worldwide. Despite recent advances in the diagnosis and intrapartum antibiotic prophylaxis (IAP) of GBS infections, it remains one of the most common causes of neonatal morbidity and mortality, causing serious infections. Furthermore, recent studies reported an increasing number of GBS infections in pregnant women and elderly. Although IAP is effective, it has several limitations, including increasing antimicrobial resistance and late GBS infection after negative antenatal screening. Maternal immunization is the most promising and effective countermeasure against GBS infection in neonates. However, no vaccine is available to date, but two types of vaccines, protein subunit and capsular polysaccharide conjugate vaccines, were investigated in clinical trials. Here, we provide an overview of the GBS vaccine development status and recent advances in the development of immunoassays to evaluate the GBS vaccine clinical efficacy.
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Affiliation(s)
- Joon Young Song
- Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jae Hyang Lim
- Department of Microbiology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Sangyong Lim
- Biotechnology Division, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea
- Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, Daejeon, Republic of Korea
| | - Zhi Yong
- Biotechnology Division, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea
- Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, Daejeon, Republic of Korea
| | - Ho Seong Seo
- Biotechnology Division, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea
- Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, Daejeon, Republic of Korea
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Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine. Infect Immun 2016; 84:2059-2075. [PMID: 27113360 DOI: 10.1128/iai.00139-16] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/20/2016] [Indexed: 11/20/2022] Open
Abstract
Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections.
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Nuccitelli A, Rinaudo CD, Maione D. Group B Streptococcus vaccine: state of the art. THERAPEUTIC ADVANCES IN VACCINES 2015; 3:76-90. [PMID: 26288735 DOI: 10.1177/2051013615579869] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Group B Streptococcus (GBS) is cause of neonatal invasive diseases as well as of severe infections in the elderly and immune-compromised patients. Despite significant advances in the prevention and treatment of neonatal disease, sepsis and meningitis caused by GBS still represent a significant public health care concern globally and additional prevention and therapeutic strategies against infection are highly desirable. The introduction of national recommended guidelines in several countries to screen pregnant women for GBS carriage and the use of antibiotics during delivery significantly reduced disease occurring within the first hours of life (early-onset disease), but it has had no effect on the late-onset diseases occurring after the first week and is not feasible in most countries. Availability of an effective vaccine against GBS would provide an effective means of controlling GBS disease. This review provides an overview of the burden of invasive disease caused by GBS in infants and adults, and highlights the strategies for the development of an effective vaccine against GBS infections.
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Affiliation(s)
| | | | - Domenico Maione
- Novartis Vaccines and Diagnostics, via Fiorentina 1, 53100 Siena, Italy
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Nilo A, Morelli L, Passalacqua I, Brogioni B, Allan M, Carboni F, Pezzicoli A, Zerbini F, Maione D, Fabbrini M, Romano MR, Hu QY, Margarit I, Berti F, Adamo R. Anti-Group B Streptococcus Glycan-Conjugate Vaccines Using Pilus Protein GBS80 As Carrier and Antigen: Comparing Lysine and Tyrosine-directed Conjugation. ACS Chem Biol 2015; 10:1737-46. [PMID: 25906283 DOI: 10.1021/acschembio.5b00247] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gram-positive Streptococcus agalactiae or group B Streptococcus (GBS) is a leading cause of invasive infections in pregnant women, newborns, and elderly people. Vaccination of pregnant women represents the best strategy for prevention of neonatal disease, and GBS polysaccharide-based conjugate vaccines are currently under clinical testing. The potential of GBS pilus proteins selected by genome-based reverse vaccinology as protective antigens for anti-streptococcal vaccines has also been demonstrated. Dressing pilus proteins with surface glycan antigens could be an attractive approach to extend vaccine coverage. We have recently developed an efficient method for tyrosine-directed ligation of large glycans to proteins via copper-free azide-alkyne [3 + 2] cycloaddition. This method enables targeting of predetermined sites of the protein, ensuring that protein epitopes are preserved prior to glycan coupling and a higher consistency in glycoconjugate batches. Herein, we compared conjugates of the GBS type II polysaccharide (PSII) and the GBS80 pilus protein obtained by classic lysine random conjugation and by the recently developed tyrosine-directed ligation. PSII conjugated to CRM197, a carrier protein used for vaccines in the market, was used as a control. We found that the constructs made from PSII and GBS80 were able to elicit murine antibodies recognizing individually the glycan and protein epitopes on the bacterial surface. The generated antibodies were efficacious in mediating opsonophagocytic killing of strains expressing exclusively PSII or GBS80 proteins. The two glycoconjugates were also effective in protecting newborn mice against GBS infection following vaccination of the dams. Altogether, these results demonstrated that polysaccharide-conjugated GBS80 pilus protein functions as a carrier comparably to CRM197, while maintaining its properties of protective protein antigen. Glycoconjugation and reverse vaccinology can, therefore, be combined to design vaccines with broad coverage. This approach opens a path to a new generation of vaccines. Tyrosine-ligation allows creation of more homogeneous vaccines, correlation of the immune response to defined connectivity points, and fine-tuning of the conjugation site in glycan-protein conjugates.
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Affiliation(s)
- Alberto Nilo
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Laura Morelli
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Irene Passalacqua
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Barbara Brogioni
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Martin Allan
- Novartis Institutes for BioMedical Research, 100 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Filippo Carboni
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Alfredo Pezzicoli
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Francesca Zerbini
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Domenico Maione
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Monica Fabbrini
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | | | - Qi-Ying Hu
- Novartis Institutes for BioMedical Research, 100 Technology Square, Cambridge, Massachusetts 02139, United States
| | | | - Francesco Berti
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
| | - Roberto Adamo
- Novartis Vaccines & Diagnostics, Via Fiorentina 1, 53100 Siena, Italy
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Cole JN, Henningham A, Gillen CM, Ramachandran V, Walker MJ. Human pathogenic streptococcal proteomics and vaccine development. Proteomics Clin Appl 2012; 2:387-410. [PMID: 21136841 DOI: 10.1002/prca.200780048] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Gram-positive streptococci are non-motile, chain-forming bacteria commonly found in the normal oral and bowel flora of warm-blooded animals. Over the past decade, a proteomic approach combining 2-DE and MS has been used to systematically map the cellular, surface-associated and secreted proteins of human pathogenic streptococcal species. The public availability of complete streptococcal genomic sequences and the amalgamation of proteomic, genomic and bioinformatic technologies have recently facilitated the identification of novel streptococcal vaccine candidate antigens and therapeutic agents. The objective of this review is to examine the constituents of the streptococcal cell wall and secreted proteome, the mechanisms of transport of surface and secreted proteins, and describe the current methodologies employed for the identification of novel surface-displayed proteins and potential vaccine antigens.
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Affiliation(s)
- Jason N Cole
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales, Australia
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9
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Dull PM, McIntosh ED. Meningococcal vaccine development – from glycoconjugates against MenACWY to proteins against MenB – potential for broad protection against meningococcal disease. Vaccine 2012; 30 Suppl 2:B18-25. [DOI: 10.1016/j.vaccine.2012.01.062] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 01/18/2012] [Accepted: 01/19/2012] [Indexed: 12/22/2022]
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Percha B, Newman MEJ, Foxman B. Transmission probabilities and durations of immunity for three pathogenic group B Streptococcus serotypes. INFECTION GENETICS AND EVOLUTION 2011; 11:1407-12. [PMID: 21605704 DOI: 10.1016/j.meegid.2011.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 04/17/2011] [Accepted: 05/07/2011] [Indexed: 11/16/2022]
Abstract
Group B Streptococcus (GBS) remains a major cause of neonatal sepsis and is an emerging cause of invasive bacterial infections. The 9 known serotypes vary in virulence, and there is little cross-immunity. Key parameters for planning an effective vaccination strategy, such as average length of immunity and transmission probabilities by serotype, are unknown. We simulated GBS spread in a population using a computational model with parameters derived from studies of GBS sexual transmission in a college dormitory. Here we provide estimates of the duration of immunity relative to the transmission probabilities for the 3 GBS serotypes most associated with invasive disease: Ia, III, and V. We also place upper limits on the durations of immunity for serotype Ia (570 days), III (1125 days) and V (260 days). Better transmission estimates are required to establish the epidemiological parameters of GBS infection and determine the best vaccination strategies to prevent GBS disease.
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Affiliation(s)
- Bethany Percha
- School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
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Johri AK, Paoletti LC, Glaser P, Dua M, Sharma PK, Grandi G, Rappuoli R. Group B Streptococcus: global incidence and vaccine development. Nat Rev Microbiol 2006; 4:932-42. [PMID: 17088932 PMCID: PMC2742968 DOI: 10.1038/nrmicro1552] [Citation(s) in RCA: 222] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An ongoing public health challenge is to develop vaccines that are effective against infectious diseases that have global relevance. Vaccines against serotypes of group B Streptococcus (GBS) that are prevalent in the United States and Europe are not optimally efficacious against serotypes common to other parts of the world. New technologies and innovative approaches are being used to identify GBS antigens that overcome serotype-specificity and that could form the basis of a globally effective vaccine against this opportunistic pathogen. This Review highlights efforts towards this goal and describes a template that can be followed to develop vaccines against other bacterial pathogens.
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Affiliation(s)
- Atul Kumar Johri
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
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Manning SD, Wood S, Kasha K, Martin D, Rioux S, Brodeur B, Davies HD. Naturally occurring antibodies for the group B streptococcal surface immunogenic protein (Sip) in pregnant women and newborn babies. Vaccine 2006; 24:6905-12. [PMID: 16844270 DOI: 10.1016/j.vaccine.2006.06.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 06/05/2006] [Accepted: 06/14/2006] [Indexed: 11/15/2022]
Abstract
Sip is a surface-exposed protein of GBS, which causes severe neonatal disease. Because Sip elicits a protective immune response in mice, we assessed whether pregnant women and newborns have Sip antibodies. Sera were collected from 644 pregnant women and 176 of their healthy newborns, and 10 newborns with GBS disease and their mothers. Using ELISA, most (99%) women and newborns (97%) had serum Sip antibodies, as did most newborns followed through 6 months. This suggests that naturally occurring Sip antibodies cross the placenta and persist into infancy, which underscores the need to study Sip further as a potential vaccine candidate.
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Abstract
Glycoconjugate vaccines, in which a cell surface carbohydrate from a micro-organism is covalently attached to an appropriate carrier protein are proving to be the most effective means to generate protective immune responses to prevent a wide range of diseases. The technology appears to be generic and applicable to a wide range of pathogens, as long as antibodies against surface carbohydrates help protect against infection. Three such vaccines, against Haemophilus influenzae type b, Neisseria meningitidis Group C and seven serotypes of Streptococcus pneumoniae, have already been licensed and many others are in development. This article discusses the rationale for the development and use of glycoconjugate vaccines, the mechanisms by which they elicit T cell-dependent immune responses and the implications of this for vaccine development, the role of physicochemical methods in the characterisation and quality control of these vaccines, and the novel products which are under development.
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Affiliation(s)
- Christopher Jones
- Laboratory for Molecular Structure, National Institute for Biological Standards and Control, Herts, UK.
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Sood RK, Fattom A. Capsular polysaccharide-protein conjugate vaccines and intravenous immunoglobulins. Expert Opin Investig Drugs 2005; 7:333-47. [PMID: 15991976 DOI: 10.1517/13543784.7.3.333] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Capsular polysaccharides (CPs), present on the surface of most pathogenic bacteria, have been recognised as virulence factors. Antibodies specific to these polysaccharides can mediate the killing of these bacteria by phagocytes in the presence of complement. The conjugation of polysaccharides to carrier proteins enhances their immunogenicity and renders the immune response T-cell dependent. The currently licensed capsular polysaccharide vaccines and polysaccharide-protein conjugate vaccines under development for the prevention of bacterial infections will be discussed in this review. Use of these vaccines for active vaccination and for the vaccination of healthy plasma donors to produce hyperimmune iv. immunoglobulins for the passive immunisation of appropriate patient populations is also discussed.
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Affiliation(s)
- R K Sood
- Walter Karakawa Microbial Pathogenesis Laboratory, Nabi, 12280 Wilkins Avenue, Rockville, MD 20852, USA
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Gan L, Xin X, Geng M, Ding J. Immunogenic comparison of two coupling methods of marine polysaccharide to bovine serum albumin. Biol Pharm Bull 2004; 27:1532-6. [PMID: 15467190 DOI: 10.1248/bpb.27.1532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two conjugates of marine polysaccharide (MPS) and bovine serum albumin (BSA) were prepared using two methods, periodate oxidation and reductive amination, with the intent of enhancing its immunogenicity. Sera samples from Balb/c mice immunized with the products named MPS-BSAp and MPS-BSAr respectively were evaluated by enzyme-linked-immunosorbent assay (ELISA). The results showed that mice immunized with MPS-BSAp produced antibodies not against MPS but rather against MPS-BSAp, while the mice immunized with MPS-BSAr produced high titer antibodies only specific for MPS. The difference was attributed to the fact that the epitopes of MPS had been changed in the coupling process by periodate oxidation. A mouse immunized with MPS-BSAr was chosen to prepare monoclonal antibodies (mAbs) specific for polysaccharide MPS. A hybridoma cell line that secreted monoclonal antibody recognizing specifically polysaccharide MPS was established.
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Affiliation(s)
- Li Gan
- Department of Pharmacology, Marine Drug and Food Institute, Ocean University of China, Qingdao, PR China
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Paoletti LC, Kasper DL. Glycoconjugate vaccines to prevent group B streptococcal infections. Expert Opin Biol Ther 2003; 3:975-84. [PMID: 12943456 DOI: 10.1517/14712598.3.6.975] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Group B Streptococcus (GBS) is an opportunistic pathogen of humans. At-risk populations include neonates born to colonised mothers, peripartum women, diabetics, and the elderly with underlying illnesses. Vaccines to prevent GBS disease have been developed by coupling purified capsular polysaccharide (CPS) antigen of GBS with an immunogenic protein carrier. Glycoconjugate vaccines against all nine currently identified GBS serotypes have been synthesised and shown to be immunogenic in mice, rabbits and baboons in preclinical trials. Healthy adults have safely received conjugate vaccines prepared with GBS types Ia, Ib, II, III, and V CPSs in Phase I and II clinical trials. These vaccines elicited CPS-specific antibody that opsonised GBS for in vitro killing by human peripheral blood leukocytes in the presence of complement. Results from these preclinical and clinical studies strongly suggest that GBS conjugate vaccines will be effective in preventing diseases caused by GBS.
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Affiliation(s)
- Lawrence C Paoletti
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 181 Longwood Avenue, Boston, Massachusetts 02115, USA.
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Martin D, Rioux S, Gagnon E, Boyer M, Hamel J, Charland N, Brodeur BR. Protection from group B streptococcal infection in neonatal mice by maternal immunization with recombinant Sip protein. Infect Immun 2002; 70:4897-901. [PMID: 12183534 PMCID: PMC128249 DOI: 10.1128/iai.70.9.4897-4901.2002] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The protective potential of antibodies directed against group B streptococcus (GBS) Sip surface protein was determined by using the mouse neonatal infection model. Rabbit Sip-specific antibodies administered passively to pregnant mice protected their pups against a GBS lethal challenge. In addition, active immunization with purified recombinant Sip protein of female CD-1 mice induced the production of specific antibodies that also confer protection to the newborn pups against GBS strains of serotypes Ia/c, Ib, II, III, and V. These data confirm that Sip-specific antibodies can cross the placenta and conferred protective immunity against GBS infections.
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Affiliation(s)
- Denis Martin
- Unité de Recherche en Vaccinologie, Centre Hospitalier Universitaire de Québec et Université Laval, Ste-Foy, Canada.
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Davies HD, Raj S, Adair C, Robinson J, McGeer A. Population-based active surveillance for neonatal group B streptococcal infections in Alberta, Canada: implications for vaccine formulation. Pediatr Infect Dis J 2001; 20:879-84. [PMID: 11734768 DOI: 10.1097/00006454-200109000-00011] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Knowledge of circulating serotypes of group B Streptococcus (GBS) is important for formulation of vaccines. There are no Canadian data on the serotype distribution of neonatal GBS isolates. METHODS Using a retrospective laboratory and health record survey between 1993 and 1994 (before introduction of Canadian prevention guidelines) and prospective active laboratory-based surveillance from 1995 to 1999 of all laboratories in Alberta, we identified 168 cases of invasive neonatal GBS infections including stillbirths among 262,398 total births; 118 of 123 (96%) isolates from 1995 to 1999 were serotyped, and the corresponding neonatal health records were reviewed. RESULTS The average annual incidence was 0.64 of 1000 total births/year. Of these 95 (57%) had early onset disease (EOD), 15 (9%) were still births and 58 (34%) had late onset disease (LOD). Eighty-one percent of EOD cases were caused by serotypes Ia, Ia/c, Ia/c/R, III, III/R and V, V/R, whereas 81% of LOD cases were caused by serotypes III and III/R. GBS serotypes containing the C protein along with serotypes III and V as a group constituted 91% (107 of 118) of all GBS cases in our population. The most common clinical presentation was bacteremia without focus (74%) followed by meningitis (14%) and pneumonia (12%). During 1995 to 1999, in addition to 13 stillbirths, there were 6 of 64 (9%) neonatal deaths among EOD cases and 1 of 46 (2%) neonatal death among LOD cases. CONCLUSIONS In this population-based study stillbirths account for a proportion of cases that are not routinely counted and represent a group for which intrapartum antibiotics would likely not be effective, but potentially preventable by vaccination. Inclusion of serotypes Ia, III and V in a conjugate vaccine or serotypes III and V conjugated with the C protein in a GBS vaccine could theoretically provide protection against the majority of GBS invasive disease in Alberta neonates.
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Affiliation(s)
- H D Davies
- Departments of Microbiology and Infectious Disease, Pediatrics, and Community Health, Child Health Research Unit, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.
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Abstract
The potency of clinical group B streptococcal (GBS) capsular polysaccharide-protein conjugate vaccines has been assessed with use of a mouse maternal vaccination-neonatal pup challenge model of GBS disease. Two of the three conjugated GBS vaccines bottled as liquid preparations showed a potency reduction from 100% to < or = 50% in 3 years; whereas all six vaccines bottled as lyophilized preparations with sucrose excipient exhibited no loss of potency during the same span of time. A reconstituted GBS conjugate vaccine remained potent and antigenically intact after 31 days' storage at 2-8 degrees C. These data suggest that lyophilization in the presence of sucrose extends the potency of GBS conjugate vaccines.
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Affiliation(s)
- L C Paoletti
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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21
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Paoletti LJ, Bradford J, Paoletti LC. A serotype VIII strain among colonizing group B streptococcal isolates in Boston, Massachusetts. J Clin Microbiol 1999; 37:3759-60. [PMID: 10523595 PMCID: PMC85754 DOI: 10.1128/jcm.37.11.3759-3760.1999] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Maternal colonization with group B Streptococcus (GBS) is a risk factor for neonatal GBS disease. Whereas serotypes Ia, Ib, II, III, and V are prevalent in the United States, types VI and VIII predominate in Japan. Recently, a serotype VIII strain was detected among 114 clinical GBS isolates from a Boston, Mass., hospital.
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Affiliation(s)
- L J Paoletti
- Clinical Microbiology Department, Channing Laboratory, Boston Massachusetts 02115, USA.
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Wessels MR, Paoletti LC, Guttormsen HK, Michon F, D'Ambra AJ, Kasper DL. Structural properties of group B streptococcal type III polysaccharide conjugate vaccines that influence immunogenicity and efficacy. Infect Immun 1998; 66:2186-92. [PMID: 9573106 PMCID: PMC108180 DOI: 10.1128/iai.66.5.2186-2192.1998] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/1997] [Accepted: 02/18/1998] [Indexed: 02/07/2023] Open
Abstract
In this study, we tested the hypothesis that the immunogenicity and protective efficacy of polysaccharide-protein conjugate vaccines are influenced by three variables: (i) molecular size of the conjugate, (ii) molecular size of the polysaccharide used for conjugation, and (iii) extent of polysaccharide-to-protein cross-linking. Type III group B Streptococcus capsular polysaccharide was linked by reductive amination at multiple sites to tetanus toxoid to create a polysaccharide-protein conjugate (III-TT). A single lot of III-TT was fractionated into small, medium, and large Mr pools. Whereas all three conferred protection in a maternal immunization-neonatal challenge model in mice, the smallest Mr conjugate evoked less polysaccharide-specific immunoglobulin G (IgG) than the two larger Mr conjugates. To test whether the molecular size of the polysaccharide used for conjugation also affected the immunogenicity of the conjugate, vaccines were synthesized using capsular polysaccharides with Mrs of 38,000, 105,000, and 349,000. Polysaccharide-specific IgG responses in mice increased with the Mr of the polysaccharides, and protective efficacy was lower for the smallest polysaccharide conjugate compared to the other two vaccines. Immunogenicity testing of a series of vaccines prepared with different degrees of polysaccharide-to-protein cross-linking demonstrated higher polysaccharide-specific antibody responses as the extent of cross-linking increased. However, opsonic activity was greatest in mouse antiserum raised to a moderately cross-linked conjugate, suggesting that some antibodies evoked by highly cross-linked conjugates were directed to a nonprotective epitope. We conclude that conjugate size, polysaccharide size, and degree of polysaccharide-protein cross-linking influence the immunogenicity and protective efficacy of III-TT conjugate vaccines.
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Affiliation(s)
- M R Wessels
- Channing Laboratory, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA.
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23
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Kling DE, Gravekamp C, Madoff LC, Michel JL. Characterization of two distinct opsonic and protective epitopes within the alpha C protein of the group B Streptococcus. Infect Immun 1997; 65:1462-7. [PMID: 9119488 PMCID: PMC175154 DOI: 10.1128/iai.65.4.1462-1467.1997] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Group B Streptococcus (GBS) is a major cause of neonatal sepsis, meningitis in early infancy, postpartum endometritis, and serious invasive infections in adults in the United States. We previously cloned, sequenced, and characterized the alpha antigen gene, bca, and showed that the alpha C protein of GBS is a trypsin-resistant, surface-associated polypeptide that contains a signal sequence, a unique N terminus, nine identical tandem repeats, and a C-terminal membrane anchor structure. Polyclonal antiserum raised to the recombinant alpha C protein and an opsonic monoclonal antibody, 4G8, raised to the native protein from GBS have been shown to be protective in a mouse model. The binding site of 4G8 has now been localized to the tandem repeat region of the alpha C protein. To determine whether the N terminus of the alpha C protein contains additional opsonic and/or protective epitopes, the sequence corresponding to the alpha C protein N terminus was subcloned into a pET vector, the expressed peptide from Escherichia coli was purified by Ni2+ affinity chromatography, and rabbit polyclonal antibodies were raised to the purified recombinant peptide. Antibodies to the alpha C protein N terminus were shown to be opsonic by an in vitro opsonophagocytosis assay. In addition, 69% of newborn mouse pups from mothers passively immunized with the antiserum to the recombinant N-terminal polypeptide of the alpha C protein were protected against lethal challenge with GBS A909. These data indicate that at least two distinct regions of the alpha C protein, the N terminus and the tandem repeat region, contain opsonic and protective epitopes.
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Affiliation(s)
- D E Kling
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, USA
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24
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Kasper DL, Paoletti LC, Wessels MR, Guttormsen HK, Carey VJ, Jennings HJ, Baker CJ. Immune response to type III group B streptococcal polysaccharide-tetanus toxoid conjugate vaccine. J Clin Invest 1996; 98:2308-14. [PMID: 8941648 PMCID: PMC507681 DOI: 10.1172/jci119042] [Citation(s) in RCA: 166] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Group B Streptococcus (GBS) is an important perinatal pathogen. Because transplacentally acquired maternal antibodies to the GBS capsular polysaccharides (CPS) confer protection, prevention of infant disease may be possible after immunization of women. Unfortunately, the purified CPS of GBS are only variably immunogenic in adults; therefore to enhance immunogenicity we have designed and developed a CPS-protein conjugate vaccine. The lability of a conformationally dependent epitope on the III CPS containing a critical sialic acid residue was important to consider in vaccine design. 100 women were randomized to receive GBS type III CPS-tetanus toxoid conjugate (III-TT) vaccine at one of three doses; unconjugated GBS type III CPS; or saline. Serum samples were obtained before immunization and 2, 4, 8, and 26 wk thereafter, and specific antibody to type III CPS was measured. Vaccines were well tolerated. In sera from recipients of the highest dose of III-TT, CPS-specific IgG levels rose from a geometric mean of 0.09 microg/ml before immunization to 4.53 microg/ml 8 wk later, whereas levels in recipients of unconjugated type III CPS rose from 0.21 microg/ml to 1.41 microg/ml. Lower doses resulted in lower antibody levels. A > or = 4-fold rise in antibody concentration was achieved in 90% of recipients of III-TT compared with 50% of those that received III CPS (P = 0.0015). Antibodies evoked by the conjugate vaccine recognized a conformationally dependent epitope of the III-CPS, promoted opsonophagocytosis and killing of GBS, and, after maternal immunization, protected neonatal mice from lethal challenge with type III GBS. We conclude that directed coupling of type III GBS polysaccharide to a carrier protein yielded a conjugate vaccine with preserved expression of a highly labile conformational epitope involving sialic acid and enhanced immunogenicity compared with uncoupled CPS.
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Affiliation(s)
- D L Kasper
- Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
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25
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Lachenauer CS, Madoff LC. A protective surface protein from type V group B streptococci shares N-terminal sequence homology with the alpha C protein. Infect Immun 1996; 64:4255-60. [PMID: 8926097 PMCID: PMC174365 DOI: 10.1128/iai.64.10.4255-4260.1996] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Infection by group B streptococci (GBS) is an important cause of bacterial disease in neonates, pregnant women, and nonpregnant adults. Historically, serotypes Ia, Ib, II, and III have been most prevalent among disease cases; recently, type V strains have emerged as important strains in the United States and elsewhere. In addition to type-specific capsular polysaccharides, many GBS strains possess surface proteins which demonstrate a laddering pattern on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and resistance to trypsin digestion. These include the alpha C protein, the R proteins, and protein Rib. Some of these proteins elicit protective antibodies in animals. We demonstrate a trypsin-resistant laddering protein purified from a type V GBS strain by mutanolysin extraction and column chromatography. This protein contains a major 90-kDa band and a series of smaller bands spaced approximately 10 kDa apart on SDS-PAGE. Cross-reactivity of the type V protein with the alpha C protein and with R1 was demonstrated on Western blot (immunoblot). N-terminal sequence analysis of the protein revealed residue identity with 17 of 18 residues at corresponding positions on the alpha protein. Western blot of SDS extracts of 41 clinical type V isolates with rabbit antiserum to the protein demonstrated a homologous protein in 25 isolates (61%); two additional strains exhibited a heterologous pattern which was also demonstrated with 4G8, a monoclonal antibody directed to the alpha C protein repeat region. Rabbit antiserum raised to the type V protein conferred protection in neonatal mice against a type V strain bearing a homologous protein. These data support the hypothesis that there exists a family of trypsin-resistant, laddering GBS surface proteins which may play a role in immunity to GBS infection.
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Affiliation(s)
- C S Lachenauer
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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26
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Hordnes K, Tynning T, Kvam AI, Jonsson R, Haneberg B. Colonization in the rectum and uterine cervix with group B streptococci may induce specific antibody responses in cervical secretions of pregnant women. Infect Immun 1996; 64:1643-52. [PMID: 8613373 PMCID: PMC173974 DOI: 10.1128/iai.64.5.1643-1652.1996] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have studied the relationships between genital or rectal carriage of group B streptococci (GBS) with the levels of systemic and mucosal antibodies to GBS in 200 women at about week 17 of pregnancy. Secretions from the uterine cervix were collected with absorbent cylindrical wicks for quantification of antibody levels with whole cell enzyme-linked immunosorbent assay. GBS were cultured from the cervix (with or without concomitant rectal colonization) of 13.5%, from the rectum (with or without concomitant cervical colonization) of 12%, and from both culture sites of 8.5% of the women. Serotypes Ia, II, and III were predominant. Compared with culture-negative women, the group of women colonized rectally had markedly elevated levels of both immunoglobulin A (IgA) and IgG antibodies to GBS in cervical secretions and also had a moderate but significant elevation of IgA antibodies in sera. Women colonized only in the cervix had increases of specific IgA and IgG antibodies in cervical secretions, but their serum antibody levels were not elevated. In cervical secretions, the increase in antibody levels in the groups of colonized women was most pronounced for the IgG isotype, indicating a mucosal immune response involving IgG as well as IgA. A close correlation was found among the levels of antibodies to each of the three GBS serotypes tested. Evidence for such cross-reacting antibodies to different serotypes of GBS, as well as to group A streptococci, was also obtained from absorption experiments. Altogether, our results show that undiluted secretions for antibody determination can be easily collected from the uterine cervix with absorbent wicks and demonstrate that colonization of GBS in the rectum and the uterine cervix may induce a systemic as well as a pronounced local immune response in the female genital tract. The findings may have implications for the development of a mucosal vaccine against GBS disease.
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Affiliation(s)
- K Hordnes
- Department of Obstetrics and Gynecology, University of Bergen, Norway.
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27
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28
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Kogan G, Uhrín D, Brisson JR, Paoletti LC, Blodgett AE, Kasper DL, Jennings HJ. Structural and immunochemical characterization of the type VIII group B Streptococcus capsular polysaccharide. J Biol Chem 1996; 271:8786-90. [PMID: 8621515 DOI: 10.1074/jbc.271.15.8786] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The type VIII capsular polysaccharide has been isolated and purified from a newly described strain of group B Streptococcus which is a leading cause of sepsis and neonatal meningitis in Japan. The polysaccharide contains D-glucose, D-galactose, L-rhamnose, and sialic acid in the molar ratio 1:1:1:1. By means of high resolution 1H nuclear magnetic resonance (1H NMR), 13C NMR, and homo- and heterocorrelated NMR, the repeating unit structure of the type VIII polysaccharide was delineated as the following, [formula: see text] Enzymatic studies established this polysaccharide as the first from which sialic acid, linked to a branched beta-D-galactopyranosyl residue, is known to be removed by bacterial neuraminidase.
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Affiliation(s)
- G Kogan
- Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada
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29
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Paoletti LC, Kennedy RC, Chanh TC, Kasper DL. Immunogenicity of group B Streptococcus type III polysaccharide-tetanus toxoid vaccine in baboons. Infect Immun 1996; 64:677-9. [PMID: 8550227 PMCID: PMC173821 DOI: 10.1128/iai.64.2.677-679.1996] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Maternal vaccination has been proposed as a rational approach for the prevention of neonatal group B streptococcal (GBS) disease. In this study, baboons were used as a nonhuman primate model to evaluate the immunogenicity of a GBS type III glycoconjugate vaccine. Type III-specific immunoglobulin G with opsonic activity was induced after vaccination with type III polysaccharide coupled to tetanus toxoid administered with an aluminum adjuvant. This suggests that baboons could be used in evaluating maternal transfer of GBS-specific antibodies by vaccination during pregnancy.
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Affiliation(s)
- L C Paoletti
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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30
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Kogan G, Brisson JR, Kasper DL, von Hunolstein C, Orefici G, Jennings HJ. Structural elucidation of the novel type VII group B Streptococcus capsular polysaccharide by high resolution NMR spectroscopy. Carbohydr Res 1995; 277:1-9. [PMID: 8548782 DOI: 10.1016/0008-6215(95)00195-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The type VII capsular polysaccharide isolated from the newly discovered group B Streptococcus (GBS) strain contains D-glucose, D-galactose, N-acetyl-D-glucosamine and N-acetylneuraminic acid in the molar ratio 2:2:1:1. High-resolution one- and two-dimensional (1D and 2D) 1H and 13C NMR spectroscopy of the native and desialylated polysaccharides showed the type VII GBS capsular polysaccharide to contain the following branched hexasaccharide repeating unit: [formula: see text] Despite extensive structural similarity with the previously described GBS polysaccharides, the type VII polysaccharide showed no cross-reaction with the heterologous antisera.
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Affiliation(s)
- G Kogan
- Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
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31
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Hordnes K, Digranes A, Haugen IL, Helland DE, Ulstein M, Jonsson R, Haneberg B. Systemic and mucosal antibody responses to group B streptococci following immunization of the colonic-rectal mucosa. J Reprod Immunol 1995; 28:247-62. [PMID: 7473434 DOI: 10.1016/0165-0378(95)00925-b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The cervico-vaginal mucosa is poorly designed for inducing a mucosal immune response, but it can effect such a response evoked at other mucosal sites. This study was undertaken to determine whether colonic-rectal immunization with group B streptococci (GBS) might induce a local cervico-vaginal immune response. Mice were immunized with either fragmented GBS rectally, whole GBS rectally, or whole GBS subcutaneously. Cholera toxin (CT) was used as an adjuvant for the rectal immunizations. Following colonic-rectal immunization with whole GBS, the mean anti-GBS IgA antibody level in vaginal secretions was 735 kU/ml, with individual values reaching 3480 kU/ml. Corresponding levels of IgA antibodies never exceeded 10 kU/ml in serum and intestinal secretions, or 90 kU/g in feces. In vaginal secretions IgA antibodies to GBS also constituted a much larger fraction of total IgA than in serum, intestinal secretions and feces. Immunizations with fragmented GBS produced much lower IgA responses. Anti-GBS IgA response at the inductive site in the colon-rectum was not significant, as opposed to a strong anti-CT IgA response. Except in serum, the anti-GBS IgG responses to colonic-rectal immunizations were generally low, or absent. The results may provide a basis for the development of mucosal vaccines against GBS-infection.
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Affiliation(s)
- K Hordnes
- Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway
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32
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Schuchat A. Group B streptococcal disease in newborns: a global perspective on prevention. Biomed Pharmacother 1995; 49:19-25. [PMID: 7749075 DOI: 10.1016/0753-3322(96)82573-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Group B Streptococcus (GBS) is an important cause of neonatal sepsis in many areas. Although incidence data are available for a minority of countries, the magnitude of illness due to this bacterium appears to vary substantially. Disease may vary due to the prevalence of asymptomatic GBS colonization, the virulence of circulating strains, the frequency of predisposing conditions such as low birth weight, or differences in obstetric practices. Approaches to prevention of neonatal GBS disease include administering antibiotics to high risk mothers intrapartum, use of intrapartum vaginal disinfectants, development of GBS vaccines, and nonspecific approaches. Determinants of prevention policies in a given area depend on the incidence of disease, the structure of health care delivery, cost-effectiveness, and cultural attitudes. Much GBS disease among newborns is now preventable, yet data on incidence are needed to guide selection of appropriate approaches to disease prevention.
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Affiliation(s)
- A Schuchat
- Childhood and Respiratory Diseases Branch, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
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33
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Abstract
It is now generally accepted that maturational immaturity of lung defense system(s) exists in the young infant and child which, together with other maturational deficiencies of immunologic systems, contribute to their undue susceptibility to infections, many of which are associated with pulmonary infections. The alveolar macrophage (AM), of central importance to lung defense, has been studied extensively in the neonatal rabbit by our group and in the human, by others. Collectively, the results indicate small numbers of morphologically and functionally immature AMs prior to birth followed by a dramatic increase within the first 24 hr. This increase coincides with the large release from type II cells of surfactant, which not only may be involved in the functional maturation of developing AMs but also, if present in large quantities, may lead to decreased activity of these cells. There is also an age-related increase in chemotactic and microbicidal activity of AMs during maturation. Deficiencies in bone marrow pools, complement and cytokines (IFN-gamma, TNF-alpha) as well as IgG isotype switching are known to occur in the neonate which may contribute to increased susceptibility to infection and which are amenable to immune interventions.
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Affiliation(s)
- J A Bellanti
- Department of Pediatrics and Microbiology/Immunology, Georgetown University Medical Center, Washington, D.C. 20007, USA
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Diaz Romero J, Outschoorn IM. Current status of meningococcal group B vaccine candidates: capsular or noncapsular? Clin Microbiol Rev 1994; 7:559-75. [PMID: 7834605 PMCID: PMC358341 DOI: 10.1128/cmr.7.4.559] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Meningococcal meningitis is a severe, life-threatening infection for which no adequate vaccine exists. Current vaccines, based on the group-specific capsular polysaccharides, provide short-term protection in adults against serogroups A and C but are ineffective in infants and do not induce protection against group B strains, the predominant cause of infection in western countries, because the purified serogroup B polysaccharide fails to elicit human bactericidal antibodies. Because of the poor immunogenicity of group B capsular polysaccharide, different noncapsular antigens have been considered for inclusion in a vaccine against this serogroup: outer membrane proteins, lipooligosaccharides, iron-regulated proteins, Lip, pili, CtrA, and the immunoglobulin A proteases. Alternatively, attempts to increase the immunogenicity of the capsular polysaccharide have been made by using noncovalent complexes with outer membrane proteins, chemical modifications, and structural analogs. Here, we review the strategies employed for the development of a vaccine for Neisseria meningitidis serogroup B; the difficulties associated with the different approaches are discussed.
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Affiliation(s)
- J Diaz Romero
- Unidad de Respuesta Immune, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
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35
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Paoletti LC, Wessels MR, Rodewald AK, Shroff AA, Jennings HJ, Kasper DL. Neonatal mouse protection against infection with multiple group B streptococcal (GBS) serotypes by maternal immunization with a tetravalent GBS polysaccharide-tetanus toxoid conjugate vaccine. Infect Immun 1994; 62:3236-43. [PMID: 8039893 PMCID: PMC302951 DOI: 10.1128/iai.62.8.3236-3243.1994] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Most cases of neonatal sepsis and meningitis caused by group B streptococci (GBS) are attributable to one of four major capsular serotypes: Ia, Ib, II, or III. Because resistance to infection with GBS has been correlated with the presence of serum antibodies to the type-specific capsular polysaccharides in both experimental animals and human neonates, efforts have been made to elicit protective immunity with GBS capsular polysaccharide vaccines. However, the GBS capsular polysaccharides alone are not highly immunogenic in either animals or human volunteers. Therefore, we and other investigators have attempted to enhance immunogenicity by coupling individual capsular polysaccharides to a carrier protein. Here we report the synthesis and immunogenicity in rabbits of a GBS type Ib polysaccharide-tetanus toxoid vaccine prepared by the direct, covalent attachment of tetanus toxoid to a selected number of sialic acid residues on the type-specific polysaccharide. In addition, the Ib polysaccharide-tetanus toxoid conjugate vaccine was combined with similar tetanus toxoid conjugates of GBS type Ia, II, and III polysaccharides to form a tetravalent GBS conjugate vaccine. Protective efficacy of the GBS tetravalent conjugate vaccine was demonstrated in a mouse maternal immunization-neonatal challenge model of GBS infection. The results support testing in human subjects of a multivalent GBS conjugate vaccine of this design, with the eventual goal of protecting newborns against GBS infection.
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Affiliation(s)
- L C Paoletti
- Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts
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36
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Madoff LC, Paoletti LC, Tai JY, Kasper DL. Maternal immunization of mice with group B streptococcal type III polysaccharide-beta C protein conjugate elicits protective antibody to multiple serotypes. J Clin Invest 1994; 94:286-92. [PMID: 7518832 PMCID: PMC296308 DOI: 10.1172/jci117319] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Group B streptococcal infection is a major cause of neonatal mortality. Antibody to the capsular polysaccharide protects against invasive neonatal disease, but immunization with capsular polysaccharides fails to elicit protective antibody in many recipients. Conjugation of the polysaccharide to tetanus toxoid has been shown to increase immune response to the polysaccharide. In animal models, C proteins of group B streptococci are also protective determinants. We examined the ability of the beta C protein to serve in the dual role of carrier for the polysaccharide and protective immunogen. Type III polysaccharide was covalently coupled to beta C protein by reductive amination. Immunization of rabbits with the polysaccharide-protein conjugate elicited high titers of antibody to both components, and the serum induced opsonophagocytic killing of type III, Ia/C, and Ib/C strains of group B streptococci. Female mice were immunized with the conjugate vaccine and then bred; 93% of neonatal pups born to these dams vaccinated with conjugate survived type III group B streptococcal challenge and 76% survived type Ia/C challenge, compared with 3% and 8% survival, respectively, in controls (P < 0.001). The beta C protein acted as an effective carrier for the type III polysaccharide while simultaneously induced protective immunity against beta C protein--containing strains of group B streptococci.
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Affiliation(s)
- L C Madoff
- Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts 02115
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37
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Affiliation(s)
- C J Baker
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030
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Wessels MR, Paoletti LC, Rodewald AK, Michon F, DiFabio J, Jennings HJ, Kasper DL. Stimulation of protective antibodies against type Ia and Ib group B streptococci by a type Ia polysaccharide-tetanus toxoid conjugate vaccine. Infect Immun 1993; 61:4760-6. [PMID: 8406875 PMCID: PMC281231 DOI: 10.1128/iai.61.11.4760-4766.1993] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Antisera elicited by type Ia group B streptococci (GBS) contain antibodies that react with both type Ia and type Ib strains. Previous studies suggested that antibodies elicited by type Ia organisms recognized a carbohydrate antigen or epitope common to Ia and Ib strains. We now report the synthesis and immunogenicity testing of a type Ia polysaccharide-tetanus toxoid (Ia-TT) conjugate vaccine. Ia-TT elicited type Ia polysaccharide-specific immunoglobulin G antibodies in all three of the rabbits inoculated. In competitive enzyme-linked immunosorbent assay, these antibodies reacted with high affinity to type Ia polysaccharide and with lower affinity to the structurally related GBS type Ib polysaccharide. Despite the lower binding affinity of the Ia-TT-induced antibodies for the type Ib polysaccharide, Ia-TT antiserum opsonized not only type Ia GBS but also type Ib GBS for killing by human blood leukocytes. Ia-TT antiserum was also evaluated in a mouse model designed to test the efficacy of maternal antibodies in protecting neonates against GBS infection. Pups born to dams that had received Ia-TT antiserum were protected against lethal challenge with either type Ia or Ib GBS. These studies using a polysaccharide-protein conjugate as an immunogen support the view that the carbohydrate immunodeterminant recognized on Ib strains by Ia antisera is a common epitope contained within the structurally related Ia and Ib capsular polysaccharides. Although antibodies elicited by Ia-TT had protective activity against both Ia and Ib strains, these antibodies reacted with lower affinity to Ib than to Ia polysaccharide.
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Affiliation(s)
- M R Wessels
- Division of Infectious Diseases, Beth Israel Hospital, Boston, Massachusetts
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39
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