1
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Dolbec D, Lehoux M, de Beauville AA, Zahn A, Di Noia JM, Segura M. Unmutated but T cell dependent IgM antibodies targeting Streptococcus suis play an essential role in bacterial clearance. PLoS Pathog 2024; 20:e1011957. [PMID: 38241393 PMCID: PMC10829992 DOI: 10.1371/journal.ppat.1011957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 01/31/2024] [Accepted: 01/08/2024] [Indexed: 01/21/2024] Open
Abstract
Streptococcus suis serotype 2 is an important encapsulated bacterial swine pathogen and zoonotic agent for which no effective vaccine exists. The interaction with B cells and the humoral response against S. suis are poorly understood despite their likely relevance for a potential vaccine. We evaluated germinal center (GC) B cell kinetics, as well as the production and role of S. suis-specific antibodies following infections in a mouse model. We found that mice infected with S. suis developed GC that peaked 13-21 days post-infection. GC further increased and persisted upon periodic reinfection that mimics real life conditions in swine farms. Anti-S. suis IgM and several IgG subclasses were produced, but antibodies against the S. suis capsular polysaccharide (CPS) were largely IgM. Interestingly, depletion of total IgG from the wild-type mice sera had no effect on bacterial killing by opsonophagocytosis in vitro. Somatic hypermutation and isotype switching were dispensable for controlling the infection or anti-CPS IgM production. However, T cell-deficient (Tcrb-/-) mice were unable to control bacteremia, produce optimal anti-CPS IgM titers, or elicit antibodies with opsonophagocytic activity. SAP deficiency, which prevents GC formation but not extrafollicular B cell responses, ablated anti S. suis-IgG production but maintained IgM production and eliminated the infection. In contrast, B cell deficient mice were unable to control bacteremia. Collectively, our results indicate that the antibody response plays a large role in immunity against S. suis, with GC-independent but T cell-dependent germline IgM being the major effective antibody specificities. Our results further highlight the importance IgM, and potentially anti-CPS antibodies, in clearing S. suis infections and provide insight for future development of S. suis vaccines.
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Affiliation(s)
- Dominic Dolbec
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Mélanie Lehoux
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Alexis Asselin de Beauville
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Astrid Zahn
- Institut de Recherches Cliniques de Montréal, Center for Immunity, Inflammation and Infectious Diseases, Quebec, Canada
| | - Javier Marcelo Di Noia
- Institut de Recherches Cliniques de Montréal, Center for Immunity, Inflammation and Infectious Diseases, Quebec, Canada
- Department of Medicine, Faculty of Sciences, University of Montreal, Montreal, Quebec, Canada
| | - Mariela Segura
- Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
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2
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Liedel C, Rieckmann K, Baums CG. A critical review on experimental Streptococcus suis infection in pigs with a focus on clinical monitoring and refinement strategies. BMC Vet Res 2023; 19:188. [PMID: 37798634 PMCID: PMC10552360 DOI: 10.1186/s12917-023-03735-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 09/14/2023] [Indexed: 10/07/2023] Open
Abstract
Streptococcus suis (S. suis) is a major pig pathogen worldwide with zoonotic potential. Though different research groups have contributed to a better understanding of the pathogenesis of S. suis infections in recent years, there are still numerous neglected research topics requiring animal infection trials. Of note, animal experiments are crucial to develop a cross-protective vaccine which is highly needed in the field. Due to the severe clinical signs associated with S. suis pathologies such as meningitis and arthritis, implementation of refinement is very important to reduce pain and distress of experimentally infected pigs. This review highlights the great diversity of clinical signs and courses of disease after experimental S. suis pig infections. We review clinical read out parameters and refinement strategies in experimental S. suis pig infections published between 2000 and 2021. Currently, substantial differences exist in describing clinical monitoring and humane endpoints. Most of the reviewed studies set the body temperature threshold of fever as high as 40.5°C. Monitoring intervals vary mainly between daily, twice a day and three times a day. Only a few studies apply scoring systems. Published scoring systems are inconsistent in their inclusion of parameters such as body temperature, feeding behavior, and respiratory signs. Locomotion and central nervous system signs are more common clinical scoring parameters in different studies by various research groups. As the heterogenicity in clinical monitoring limits the comparability between studies we hope to initiate a discussion with this review leading to an agreement on clinical read out parameters and monitoring intervals among S. suis research groups.
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Affiliation(s)
- Carolin Liedel
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, An den Tierkliniken 29, Leipzig, 04103, Germany
| | - Karoline Rieckmann
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, An den Tierkliniken 29, Leipzig, 04103, Germany
| | - Christoph G Baums
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, An den Tierkliniken 29, Leipzig, 04103, Germany.
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3
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Kuttel MM. Comparative Molecular Modelling of Capsular Polysaccharide Conformations in Streptococcus suis Serotypes 1, 2, 1/2 and 14 Identifies Common Epitopes for Antibody Binding. Front Mol Biosci 2022; 9:830854. [PMID: 35211512 PMCID: PMC8861514 DOI: 10.3389/fmolb.2022.830854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/18/2022] [Indexed: 11/21/2022] Open
Abstract
Streptococcus suis is an encapsulated, commensal, potentially pathogenic bacterium that infects swine globally and causes sporadic life-threatening zoonotic septicemia and meningitis infections in humans. The capsular polysaccharide is a primary virulence factor for S. suis. As S. suis serotype 2 is the most prevalent serotype globally, the serotype 2 CPS is the primary target of current efforts to develop an effective glycoconjugate veterinary vaccine against S. suis. Possible cross-protection with related serotypes would broaden the coverage of a vaccine. The CPS in serotypes 2 and 1/2 differ at a single residue (Gal versus GalNAc), and both are similar to serotypes 1 and 14: all contain a terminal sialic acid on a side chain. However, despite this similarity, there is complex pattern of cross-protection for these serotypes, with varying estimations of the importance of sialic acid in a protective epitope. Further, a pentasaccharide without the terminal sialic acid has been identified as minimal epitope for serotype 2. Here we use molecular simulation to model the molecule conformations of the CPS in serotypes 2, 1/2, 1 and 14, as well as three vaccine candidate oligosaccharides. The common epitopes we identify assist in rationalizing the apparently contradictory immunological data and provide a basis for rational design of S. suis vaccines in the future.
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4
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Nothaft H, Perez-Muñoz ME, Yang T, Murugan AVM, Miller M, Kolarich D, Plastow GS, Walter J, Szymanski CM. Improving Chicken Responses to Glycoconjugate Vaccination Against Campylobacter jejuni. Front Microbiol 2021; 12:734526. [PMID: 34867850 PMCID: PMC8637857 DOI: 10.3389/fmicb.2021.734526] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/04/2021] [Indexed: 01/03/2023] Open
Abstract
Campylobacter jejuni is a common cause of diarrheal disease worldwide. Human infection typically occurs through the ingestion of contaminated poultry products. We previously demonstrated that an attenuated Escherichia coli live vaccine strain expressing the C. jejuni N-glycan on its surface reduced the Campylobacter load in more than 50% of vaccinated leghorn and broiler birds to undetectable levels (responder birds), whereas the remainder of the animals was still colonized (non-responders). To understand the underlying mechanism, we conducted three vaccination and challenge studies using 135 broiler birds and found a similar responder/non-responder effect. Subsequent genome-wide association studies (GWAS), analyses of bird sex and levels of vaccine-induced IgY responses did not correlate with the responder versus non-responder phenotype. In contrast, antibodies isolated from responder birds displayed a higher Campylobacter-opsonophagocytic activity when compared to antisera from non-responder birds. No differences in the N-glycome of the sera could be detected, although minor changes in IgY glycosylation warrant further investigation. As reported before, the composition of the microbiota, particularly levels of OTU classified as Clostridium spp., Ruminococcaceae and Lachnospiraceae are associated with the response. Transplantation of the cecal microbiota of responder birds into new birds in combination with vaccination resulted in further increases in vaccine-induced antigen-specific IgY responses when compared to birds that did not receive microbiota transplants. Our work suggests that the IgY effector function and microbiota contribute to the efficacy of the E. coli live vaccine, information that could form the basis for the development of improved vaccines targeted at the elimination of C. jejuni from poultry.
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Affiliation(s)
- Harald Nothaft
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Maria Elisa Perez-Muñoz
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Tianfu Yang
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Abarna V M Murugan
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD, Australia
| | | | - Daniel Kolarich
- Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, QLD, Australia.,ARC Centre of Excellence for Nanoscale BioPhotonics, Griffith University, Southport, QLD, Australia
| | - Graham S Plastow
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada.,Livestock Gentec, Edmonton, AB, Canada
| | - Jens Walter
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Christine M Szymanski
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Department of Microbiology and Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
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Sulong P, Anudit N, Nuanualsuwan S, Mariela S, Khantasup K. Application of phage display technology for the production of antibodies against Streptococcus suis serotype 2. PLoS One 2021; 16:e0258931. [PMID: 34699547 PMCID: PMC8547629 DOI: 10.1371/journal.pone.0258931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 10/08/2021] [Indexed: 11/20/2022] Open
Abstract
Streptococcus suis (S. suis) serotype 2 infection is a problem in the swine industry and responsible for most cases of human infection worldwide. Since current multiplex PCR cannot differentiate between serotypes 2 and 1/2, then serotype-specific antibodies (Abs) are required for serotype identification to confirm infection by serotype 2. This study aimed to generate Abs specific to S. suis serotype 2 by phage display from a human heavy chain variable domain (VH) antibody library. For biopanning, whole cells of S. suis serotype 2 were used as the target antigen. With increasing selection stringency, we could select the VH Abs that specifically bound to a S. suis serotype 2 surface antigen, which was identified as the capsular polysaccharide (CPS). From ELISA analysis, the specific phage clone 47B3 VH with the highest binding activity to S. suis serotype 2 was selected and shown to have no cross-reactivity with S. suis serotypes 1/2, 1, and 14 that shared a common epitope with serotype 2 and occasionally cause infections in human. Moreover, no cross-reactivity with other bacteria that can be found in septic blood specimens was also observed. Then, 47B3 VH was successfully expressed as soluble 47B3 VH in E. coli TG1. The soluble 47B3 VH crude extract was further tested for its binding ability in a dose-dependent ELISA assay. The results indicated that the activity of phage clone 47B3 was still retained even when the Ab occurred in the soluble form. A quellung reaction demonstrated that the soluble 47B3 VH Ab could show bioactivity by differentiation between S. suis serotypes 2 and 1/2. Thus, it will be beneficial to use this VH Ab in the diagnosis of disease or discrimination of S. suis serotypes Furthermore, the results described here could motivate the use of phage display VH platform to produce serotyping antibodies.
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Affiliation(s)
- Pattarawadee Sulong
- The Medical Microbiology Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Natsinee Anudit
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Suphachai Nuanualsuwan
- Department of Veterinary Public Health, Faculty of Veterinary Sciences, Chulalongkorn University, Bangkok, Thailand
- Food Risk Hub, Research Unit of Chulalongkorn University, Bangkok, Thailand
| | - Segura Mariela
- Laboratory of Immunology, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Quebec, Canada
| | - Kannika Khantasup
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Food Risk Hub, Research Unit of Chulalongkorn University, Bangkok, Thailand
- Vaccines and Therapeutic Proteins Research Group, the Special Task Force for Activating Research (STAR), Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
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6
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Obradovic MR, Corsaut L, Dolbec D, Gottschalk M, Segura M. Experimental evaluation of protection and immunogenicity of Streptococcus suis bacterin-based vaccines formulated with different commercial adjuvants in weaned piglets. Vet Res 2021; 52:133. [PMID: 34666827 PMCID: PMC8527783 DOI: 10.1186/s13567-021-01004-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 10/01/2021] [Indexed: 12/04/2022] Open
Abstract
Streptococcus suis is an important swine pathogen responsible for economic losses to the swine industry worldwide. There is no effective commercial vaccine against S. suis. The use of autogenous (“bacterin”) vaccines to control S. suis outbreaks is a frequent preventive measure in the field, although scientific data on immunogenicity and reduction in mortality and morbidity are scarce. The goal of our study is to experimentally evaluate the immunogenicity and protective efficacy against homologous challenge in weaned piglets of a S. suis serotype 2 bacterin-based vaccine formulated with six different commercial adjuvants (Alhydrogel®, Emulsigen®-D, Quil-A®, Montanide™ ISA 206 VG, Montanide™ ISA 61 VG, and Montanide™ ISA 201 VG). The vaccine formulated with Montanide™ ISA 61 VG induced a significant increase in anti-S. suis antibodies, including both IgG1 and IgG2 subclasses, protected against mortality and significantly reduced morbidity and severity of clinical signs. Vaccines formulated with Montanide ISA 206 VG or Montanide ISA 201 VG also induced a significant increase in anti-S. suis antibodies and showed partial protection and reduction of clinical signs severity. Vaccines formulated with Alhydrogel®, Emulsigen®-D, or Quil-A® induced a low and IgG1-shifted antibody response and failed to protect vaccinated piglets against a homologous challenge. In conclusion, the type of adjuvant used in the vaccine formulation significantly influenced the immune response and efficacy of the vaccine against a homologous challenge.
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Affiliation(s)
- Milan R Obradovic
- Research Group On Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Lorelei Corsaut
- Research Group On Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Dominic Dolbec
- Research Group On Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Marcelo Gottschalk
- Research Group On Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada.
| | - Mariela Segura
- Research Group On Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada.
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7
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Weiße C, Dittmar D, Jakóbczak B, Florian V, Schütze N, Alber G, Klose K, Michalik S, Valentin-Weigand P, Völker U, Baums CG. Immunogenicity and protective efficacy of a Streptococcus suis vaccine composed of six conserved immunogens. Vet Res 2021; 52:112. [PMID: 34433500 PMCID: PMC8390293 DOI: 10.1186/s13567-021-00981-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/20/2021] [Indexed: 01/12/2023] Open
Abstract
A vaccine protecting against different Streptococcus suis serotypes is highly needed in porcine practice to improve animal welfare and reduce the use of antibiotics. We hypothesized that immunogens prominently recognized by convalescence sera but significantly less so by sera of susceptible piglets are putative protective antigens. Accordingly, we investigated immunogenicity and protective efficacy of a multicomponent vaccine including six main conserved immunogens, namely SSU0934, SSU1869, SSU0757, SSU1950, SSU1664 and SSU0187. Flow cytometry confirmed surface expression of all six immunogens in S. suis serotypes 2, 9 and 14. Although prime-booster vaccination after weaning resulted in significantly higher specific IgG levels against all six immunogens compared to the placebo-treated group, no significant differences between bacterial survival in blood from either vaccinated or control animals were recorded for serotype 2, 9 and 14 strains. Furthermore, vaccinated piglets were not protected against morbidity elicited through intranasal challenge with S. suis serotype 14. As ~50% of animals in both groups did not develop disease, we investigated putative other correlates of protection. Induction of reactive oxygen species (ROS) in blood granulocytes was not associated with vaccination but correlated with protection as all piglets with >5% ROS survived the challenge. Based on these findings we discuss that the main immunogens of S. suis might actually not be a priori good candidates for protective antigens. On the contrary, expression of immunogens that evoke antibodies that do not mediate killing of this pathogen might constitute an evolutionary advantage conserved in many different S. suis strains.
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Affiliation(s)
- Christine Weiße
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Denise Dittmar
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | | | | | - Nicole Schütze
- Institute of Immunology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Gottfried Alber
- Institute of Immunology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Kristin Klose
- Institute of Pathology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Stephan Michalik
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Peter Valentin-Weigand
- Department of Infectious Diseases, Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Uwe Völker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Christoph Georg Baums
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany.
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8
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Mayer L, Bornemann N, Lehnert S, de Greeff A, Strutzberg-Minder K, Rieckmann K, Baums CG. Survival patterns of Streptococcus suis serotypes 1 and 14 in porcine blood indicate cross-reactive bactericidal antibodies in naturally infected pigs. Vet Microbiol 2021; 260:109183. [PMID: 34304027 DOI: 10.1016/j.vetmic.2021.109183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
Streptococcus suis serotype (cps) 1 and cps14 have been detected in association with severe diseases such as meningitis and polyarthritis in pigs. Though these two cps are very similar, only cps14 is an important zoonotic agent in Asia and only cps1 is described to be associated with diseases in suckling piglets rather than weaning piglets. The main objective of this study was to assess restriction of survival of cps14 and cps1 in porcine blood by IgG and IgM putatively cross-reacting with these two cps. Furthermore, we differentiate recent European cps1/14 strains by agglutination, cpsK sequencing, MLST and virulence-associated gene profiling. Our data confirmed cps1 of clonal complex 1 as an important pathotype causing polyarthritis in suckling piglets in Europe. The experimental design included also bactericidal assays with blood samples drawn at different ages of piglets naturally infected with different S. suis cps types including cps1 but not cps14. We report survival of a cps1 and a cps14 strain (both of sequence type 1) in blood of suckling piglets with high levels of maternal IgG binding to the bacterial surface. In contrast, killing of cps1 and cps14 was recorded in older piglets due to an increase of IgM as demonstrated by specific cleavage of IgM. Heterologous absorption of antibodies with cps1 or cps14 is sufficient to significantly increase the survival of the other cps. In conclusion, IgM elicited by natural S. suis infection is crucial for killing of S. suis cps1 and cps14 in older weaning piglets and has most likely the potential to cross-react between cps1 and cps14.
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Affiliation(s)
- L Mayer
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - N Bornemann
- IVD Innovative Veterinary Diagnostics (IVD GmbH), Albert-Einstein-Str. 5, 30926, Seelze, Germany
| | - S Lehnert
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - A de Greeff
- Wageningen Bioveterinary Research, part of Wageningen University and Research, Lelystad, the Netherlands
| | - K Strutzberg-Minder
- IVD Innovative Veterinary Diagnostics (IVD GmbH), Albert-Einstein-Str. 5, 30926, Seelze, Germany
| | - K Rieckmann
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - C G Baums
- Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany.
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9
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Zhang S, Sella M, Sianturi J, Priegue P, Shen D, Seeberger PH. Discovery of Oligosaccharide Antigens for Semi-Synthetic Glycoconjugate Vaccine Leads against Streptococcus suis Serotypes 2, 3, 9 and 14*. Angew Chem Int Ed Engl 2021; 60:14679-14692. [PMID: 33852172 PMCID: PMC8252040 DOI: 10.1002/anie.202103990] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Indexed: 01/03/2023]
Abstract
Streptococcus suis bacteria are one of the most serious health problems for pigs and an emerging zoonotic agent in humans working in the swine industry. S. suis bacteria express capsular polysaccharides (CPS) a major bacterial virulence factor that define the serotypes. Oligosaccharides resembling the CPS of S. suis serotypes 2, 3, 9, and 14 have been synthesized, glycans related to serotypes 2 and 9 were placed on glycan array surfaces to screen blood from infected pigs. Lead antigens for the development of semi-synthetic S. suis serotypes 2 and 9 glycoconjugate veterinary vaccines were identified in this way.
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Affiliation(s)
- Shuo Zhang
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Mauro Sella
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Julinton Sianturi
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Patricia Priegue
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Dacheng Shen
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
- Present address: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Peter H Seeberger
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
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Zhang S, Sella M, Sianturi J, Priegue P, Shen D, Seeberger PH. Discovery of Oligosaccharide Antigens for Semi‐Synthetic Glycoconjugate Vaccine Leads against
Streptococcus suis
Serotypes 2, 3, 9 and 14**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103990] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Shuo Zhang
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
- Institute of Chemistry and Biochemistry Freie Universität Berlin Arnimallee 22 14195 Berlin Germany
| | - Mauro Sella
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
| | - Julinton Sianturi
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
| | - Patricia Priegue
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
- Institute of Chemistry and Biochemistry Freie Universität Berlin Arnimallee 22 14195 Berlin Germany
| | - Dacheng Shen
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
- Present address: Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
| | - Peter H. Seeberger
- Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
- Institute of Chemistry and Biochemistry Freie Universität Berlin Arnimallee 22 14195 Berlin Germany
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11
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Obradovic MR, Segura M, Segalés J, Gottschalk M. Review of the speculative role of co-infections in Streptococcus suis-associated diseases in pigs. Vet Res 2021; 52:49. [PMID: 33743838 PMCID: PMC7980725 DOI: 10.1186/s13567-021-00918-w] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 02/25/2021] [Indexed: 12/21/2022] Open
Abstract
Streptococcus suis is one of the most important bacterial swine pathogens affecting post-weaned piglets, causing mainly meningitis, arthritis and sudden death. It not only results in severe economic losses but also raises concerns over animal welfare and antimicrobial resistance and remains an important zoonotic agent in some countries. The definition and diagnosis of S. suis-associated diseases can be complex. Should S. suis be considered a primary or secondary pathogen? The situation is further complicated when referring to respiratory disease, since the pathogen has historically been considered as a secondary pathogen within the porcine respiratory disease complex (PRDC). Is S. suis a respiratory or strictly systemic pathogen? S. suis is a normal inhabitant of the upper respiratory tract, and the presence of potentially virulent strains alone does not guarantee the appearance of clinical signs. Within this unclear context, it has been largely proposed that co-infection with some viral and bacterial pathogens can significantly influence the severity of S. suis-associated diseases and may be the key to understanding how the infection behaves in the field. In this review, we critically addressed studies reporting an epidemiological link (mixed infections or presence of more than one pathogen at the same time), as well as in vitro and in vivo studies of co-infection of S. suis with other pathogens and discussed their limitations and possibilities for improvement and proposed recommendations for future studies.
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Affiliation(s)
- Milan R Obradovic
- Groupe de Recherche Sur Les Maladies Infectieuses en Production Animale (GREMIP), Centre de Recherche en Infectiologie Porcine et Aviaire (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Mariela Segura
- Groupe de Recherche Sur Les Maladies Infectieuses en Production Animale (GREMIP), Centre de Recherche en Infectiologie Porcine et Aviaire (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Joaquim Segalés
- UAB, CReSA (IRTA-UAB), Campus de la UAB, 08193, Bellaterra (Cerdanyola del Vallès), Spain.,Departament de Sanitat I Anatomia Animals, Facultat de Veterinària, UAB, 08193, Bellaterra (Cerdanyola del Vallès), Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), 08193, Bellaterra, Barcelona, Spain
| | - Marcelo Gottschalk
- Groupe de Recherche Sur Les Maladies Infectieuses en Production Animale (GREMIP), Centre de Recherche en Infectiologie Porcine et Aviaire (CRIPA), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte, Saint-Hyacinthe, QC, J2S 2M2, Canada.
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12
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Adjuvants for swine vaccines: Mechanisms of actions and adjuvant effects. Vaccine 2020; 38:6659-6681. [DOI: 10.1016/j.vaccine.2020.08.054] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 02/07/2023]
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13
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Comparative Study of Immunogenic Properties of Purified Capsular Polysaccharides from Streptococcus suis Serotypes 3, 7, 8, and 9: the Serotype 3 Polysaccharide Induces an Opsonizing IgG Response. Infect Immun 2020; 88:IAI.00377-20. [PMID: 32747605 PMCID: PMC7504959 DOI: 10.1128/iai.00377-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 07/30/2020] [Indexed: 12/17/2022] Open
Abstract
Streptococcus suis is an encapsulated bacterium and one of the most important swine pathogens and a zoonotic agent for which no effective vaccine exists. Bacterial capsular polysaccharides (CPSs) are poorly immunogenic, but anti-CPS antibodies are essential to the host defense against encapsulated bacteria. In addition to the previously known serotypes 2 and 14, which are nonimmunogenic, we have recently purified and described the CPS structures for serotypes 1, 1/2, 3, 7, 8, and 9. Streptococcus suis is an encapsulated bacterium and one of the most important swine pathogens and a zoonotic agent for which no effective vaccine exists. Bacterial capsular polysaccharides (CPSs) are poorly immunogenic, but anti-CPS antibodies are essential to the host defense against encapsulated bacteria. In addition to the previously known serotypes 2 and 14, which are nonimmunogenic, we have recently purified and described the CPS structures for serotypes 1, 1/2, 3, 7, 8, and 9. Here, we aimed to elucidate how these new structurally diverse CPSs interact with the immune system to generate anti-CPS antibody responses. CPS-stimulated dendritic cells produced significant levels of C–C motif chemokine ligand 3 (CCL3), partially via Toll-like receptor 2 (TLR2)- and myeloid differentiation factor 88-dependent pathways, and CCL2, via TLR-independent mechanisms. Mice immunized with purified serotype 3 CPS adjuvanted with TiterMax Gold produced an opsonizing IgG response, whereas other CPSs or adjuvants were negative. Mice hyperimmunized with heat-killed S. suis serotypes 3 and 9 both produced anti-CPS type 1 IgGs, whereas serotypes 7 and 8 remained negative. Also, mice infected with sublethal doses of S. suis serotype 3 produced primary anti-CPS IgM and IgG responses, of which only IgM were boosted after a secondary infection. In contrast, mice sublethally infected with S. suis serotype 9 produced weak anti-CPS IgM and IgG responses following a secondary infection. This study provides important information on the divergent evolution of CPS serotypes with highly different structural and/or biochemical properties within S. suis and their interaction with the immune system.
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14
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Field Study on the Immunological Response and Protective Effect of a Licensed Autogenous Vaccine to Control Streptococcus suis Infections in Post-Weaned Piglets. Vaccines (Basel) 2020; 8:vaccines8030384. [PMID: 32674276 PMCID: PMC7565864 DOI: 10.3390/vaccines8030384] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/17/2020] [Accepted: 07/03/2020] [Indexed: 01/02/2023] Open
Abstract
Streptococcus suis is one of the most important bacterial pathogens in weaned piglets and responsible for serious economic losses to the swine industry. Currently, mostly autogenous vaccines composed of killed bacteria (bacterins) are available. However, immunological and protective data from field studies are missing. We report for the first time a comparative field study on the immunological response induced by an autogenous vaccine applied to either piglets or sows in a farm with recurrent S. suis problems. (I) Piglets from non-vaccinated sows received an autogenous bacterin during the first week and at three weeks of age. (II) Sows received the vaccine at five and three weeks pre-farrowing and piglets were non-vaccinated. Levels, isotype profile and opsonophagocytosis capacity of the serum antibodies induced by vaccination were evaluated. Vaccination of piglets failed to induce an active immune response. Vaccination of sows induced a significant increase in anti-S. suis antibodies, mainly composed of IgG1. However, isotype switching was modulated by the S. suis serotype included in the vaccine formulation. Despite this antibody increase in vaccinated sows, transfer of maternal immunity to piglets was not different from the control group (i.e., piglets from non-vaccinated sows). Notably, levels of maternal antibodies in piglets were already very high with marked opsonophagocytosis capacity at one week of age, independently of the vaccination program. However, their levels decreased by three weeks of age, indicating possible absence of antibodies in the post-weaning high-risk period. These observations correlated with lack of clinical protection in the farm. Overall, a piglet or a sow vaccination program herein mostly failed to induce lasting protection in nursery piglets. An improvement of vaccine formulation or an optimized program may be required.
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15
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Wenzel CQ, Mills DC, Dobruchowska JM, Vlach J, Nothaft H, Nation P, Azadi P, Melville SB, Carlson RW, Feldman MF, Szymanski CM. An atypical lipoteichoic acid from Clostridium perfringens elicits a broadly cross-reactive and protective immune response. J Biol Chem 2020; 295:9513-9530. [PMID: 32424044 DOI: 10.1074/jbc.ra119.009978] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 05/02/2020] [Indexed: 12/14/2022] Open
Abstract
Clostridium perfringens is a leading cause of food-poisoning and causes avian necrotic enteritis, posing a significant problem to both the poultry industry and human health. No effective vaccine against C. perfringens is currently available. Using an antiserum screen of mutants generated from a C. perfringens transposon-mutant library, here we identified an immunoreactive antigen that was lost in a putative glycosyltransferase mutant, suggesting that this antigen is likely a glycoconjugate. Following injection of formalin-fixed whole cells of C. perfringens HN13 (a laboratory strain) and JGS4143 (chicken isolate) intramuscularly into chickens, the HN13-derived antiserum was cross-reactive in immunoblots with all tested 32 field isolates, whereas only 5 of 32 isolates were recognized by JGS4143-derived antiserum. The immunoreactive antigens from both HN13 and JGS4143 were isolated, and structural analysis by MALDI-TOF-MS, GC-MS, and 2D NMR revealed that both were atypical lipoteichoic acids (LTAs) with poly-(β1→4)-ManNAc backbones substituted with phosphoethanolamine. However, although the ManNAc residues in JGS4143 LTA were phosphoethanolamine-modified, a few of these residues were instead modified with phosphoglycerol in the HN13 LTA. The JGS4143 LTA also had a terminal ribose and ManNAc instead of ManN in the core region, suggesting that these differences may contribute to the broadly cross-reactive response elicited by HN13. In a passive-protection chicken experiment, oral challenge with C. perfringens JGS4143 lead to 22% survival, whereas co-gavage with JGS4143 and α-HN13 antiserum resulted in 89% survival. This serum also induced bacterial killing in opsonophagocytosis assays, suggesting that HN13 LTA is an attractive target for future vaccine-development studies.
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Affiliation(s)
- Cory Q Wenzel
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,VaxAlta Inc., Edmonton, Alberta, Canada.,Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Dominic C Mills
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | | | - Jiri Vlach
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Harald Nothaft
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,VaxAlta Inc., Edmonton, Alberta, Canada.,Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Patrick Nation
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Stephen B Melville
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Russell W Carlson
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Mario F Feldman
- VaxAlta Inc., Edmonton, Alberta, Canada.,Department of Molecular Microbiology, Washington University of Medicine, St. Louis, Missouri, USA
| | - Christine M Szymanski
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada .,VaxAlta Inc., Edmonton, Alberta, Canada.,Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
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16
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Rieckmann K, Pendzialek SM, Vahlenkamp T, Baums CG. A critical review speculating on the protective efficacies of autogenous Streptococcus suis bacterins as used in Europe. Porcine Health Manag 2020; 6:12. [PMID: 32391166 PMCID: PMC7201539 DOI: 10.1186/s40813-020-00150-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/20/2020] [Indexed: 11/10/2022] Open
Abstract
Background Streptococcus (S.) suis is a major porcine pathogen causing high morbidity worldwide. This includes well-managed herds with high hygiene standards. In Europe, no licensed vaccine is available. As practitioners are obliged to reduce the use of antibiotics, autogenous S. suis vaccines have become very popular in Europe. Main body Autogenous vaccines (AV) are generally neither tested for safety, immunogenicity nor protective efficacy, which leads to substantial uncertainties regarding control of disease and return on investment. Here, S. suis publications are reviewed that include important data on epidemiology, pathologies and bacterin vaccination relevant for the use of AV in the field. Differences between herds such as the porcine reproductive and respiratory syndrome virus infection status and the impact of specific S. suis pathotypes are probably highly relevant for the outcome of immunoprophylaxis using autogenous S. suis bacterins. Thus, a profound diagnosis of the herd status is crucial for management of expectations and successful implementation of AV as a tool to control S. suis disease. Induction of opsonizing antibodies is an in vitro correlate of protective immunity elicited by S. suis bacterins. However, opsonophagocytosis assays are difficult to include in the portfolio of diagnostic services. Conclusion Autogenous S. suis bacterins are associated with limitations and risks of failure, which can partly be managed through improvement of diagnostics.
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Affiliation(s)
- Karoline Rieckmann
- 1Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, University Leipzig, An den Tierkliniken 29, 04103 Leipzig, Germany
| | - Sophia-Mareike Pendzialek
- 1Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, University Leipzig, An den Tierkliniken 29, 04103 Leipzig, Germany
| | - Thomas Vahlenkamp
- 2Institute of Virology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, University Leipzig, Leipzig, Germany
| | - Christoph G Baums
- 1Institute of Bacteriology and Mycology, Centre for Infectious Diseases, Faculty of Veterinary Medicine, University Leipzig, An den Tierkliniken 29, 04103 Leipzig, Germany
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17
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Budde I, Litschko C, Führing JI, Gerardy-Schahn R, Schubert M, Fiebig T. An enzyme-based protocol for cell-free synthesis of nature-identical capsular oligosaccharides from Actinobacillus pleuropneumoniae serotype 1. J Biol Chem 2020; 295:5771-5784. [PMID: 32152227 PMCID: PMC7186170 DOI: 10.1074/jbc.ra120.012961] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/09/2020] [Indexed: 11/06/2022] Open
Abstract
Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.
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Affiliation(s)
- Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany.
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18
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Dumesnil A, Martelet L, Grenier D, Auger JP, Harel J, Nadeau E, Gottschalk M. Enolase and dipeptidyl peptidase IV protein sub-unit vaccines are not protective against a lethal Streptococcus suis serotype 2 challenge in a mouse model of infection. BMC Vet Res 2019; 15:448. [PMID: 31823789 PMCID: PMC6905021 DOI: 10.1186/s12917-019-2196-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 11/26/2019] [Indexed: 02/02/2023] Open
Abstract
Background Streptococcus suis is a major swine pathogen causing arthritis, meningitis and sudden death in post-weaning piglets and is also a zoonotic agent. S. suis comprises 35 different serotypes of which the serotype 2 is the most prevalent in both pigs and humans. In the absence of commercial vaccines, bacterins (mostly autogenous), are used in the field, with controversial results. In the past years, the focus has turned towards the development of sub-unit vaccine candidates. However, published results are sometimes contradictory regarding the protective effect of a same candidate. Moreover, the adjuvant used may significantly influence the protective capacity of a given antigen. This study focused on two protective candidates, the dipeptidyl peptidase IV (DPPIV) and the enolase (SsEno). Both proteins are involved in S. suis pathogenesis, and while contradictory protection results have been obtained with SsEno in the past, no data on the protective capacity of DPPIV was available. Results Results showed that among all the field strains tested, 86 and 88% were positive for the expression of the SsEno and DPPIV proteins, respectively, suggesting that they are widely expressed by strains of different serotypes. However, no protection was obtained after two vaccine doses in a CD-1 mouse model of infection, regardless of the use of four different adjuvants. Even though no protection was obtained, significant amounts of antibodies were produced against both antigens, and this regardless of the adjuvant used. Conclusions Taken together, these results demonstrate that S. suis DPPIV and SsEno are probably not good vaccine candidates, at least not in the conditions evaluated in this study. Further studies in the natural host (pig) should still be carried out. Moreover, this work highlights the importance of confirming results obtained by different research groups.
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Affiliation(s)
- Audrey Dumesnil
- Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St.,, Saint-Hyacinthe, QC, J2S 2M2, Canada.,Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada
| | - Léa Martelet
- Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St.,, Saint-Hyacinthe, QC, J2S 2M2, Canada.,Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada
| | - Daniel Grenier
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada.,Oral Ecology Research Group (GREB), Faculty of Dentistry, Laval University, Quebec City, Quebec, Canada
| | - Jean-Philippe Auger
- Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St.,, Saint-Hyacinthe, QC, J2S 2M2, Canada.,Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada
| | - Josée Harel
- Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St.,, Saint-Hyacinthe, QC, J2S 2M2, Canada.,Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada
| | - Eric Nadeau
- Prevtec Microbia Inc. 3395 Casavant W. Blvd, Saint-Hyacinthe, QC, J2S 0B8, Canada
| | - Marcelo Gottschalk
- Groupe de recherche sur les maladies infectieuses en production animale (GREMIP), Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St.,, Saint-Hyacinthe, QC, J2S 2M2, Canada. .,Swine and Poultry Infectious Diseases Research Center (CRIPA), Montreal, Quebec, Canada.
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19
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Clonal expansion of a virulent Streptococcus suis serotype 9 lineage distinguishable from carriage subpopulations. Sci Rep 2019; 9:15429. [PMID: 31659179 PMCID: PMC6817849 DOI: 10.1038/s41598-019-51576-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 09/25/2019] [Indexed: 12/25/2022] Open
Abstract
Streptococcus suis is a porcine pathogen, causing severe invasive infections. S. suis serotype 9 is increasingly causing disease in Dutch and Chinese pig herds, but it is unknown whether all serotype 9 isolates are equally virulent and markers that can identify virulent strains are not available. Therefore, discrimination between virulent isolates and carriage isolates typically not associated with disease, is currently not possible. We collected tonsillar S. suis isolates from 6 herds not previously diagnosed with S. suis infections, and clinical S. suis isolates of previously diseased pigs. We confirmed the virulence of a virulent type strain and one representative clinical isolate, and the lack of virulence of two carriage isolates, in a pig infection model. Phylogenetic analysis of whole genome sequences of 124 isolates resulted in 10 groups, of which two were almost uniquely populated by clinical isolates. The population structure of S. suis serotype 9 appears highly diverse. However, analysis of the capsule loci sequences showed variation in a single region which fully correlated with a virulent genotype. Transmission electron microscopy suggested differences in capsule thickness between carriage and clinical genotypes. In conclusion, we found that that the S. suis serotype 9 population in the Netherlands is diverse. A distinct virulence-associated lineage was identified and could be discriminated based on the capsule locus sequence. Whilst the difference in virulence cannot be directly attributed to the DNA sequence, the correlation of capsule locus sequence with virulence could be used in the development of diagnostic tests to identify potential virulent S. suis serotype 9 in pigs.
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20
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Biosynthesis and regulation mechanisms of the Pasteurella multocida capsule. Res Vet Sci 2019; 127:82-90. [PMID: 31678457 DOI: 10.1016/j.rvsc.2019.10.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 09/05/2019] [Accepted: 10/21/2019] [Indexed: 12/27/2022]
Abstract
Pasteurella multocida possesses a polysaccharide capsule composed of a viscous surface layer that acts as a critical structural component and virulence factor. Capsular polysaccharides are structurally similar to vertebrate glycosaminoglycans, providing an immunological mechanism for bacterial molecular mimicry, resistance to phagocytosis, and immune evasion during the infection process. In recent years, a series of important research advances have been made in understanding the biosynthesis and regulatory aspects of the P. multocida capsule. This review systematically examines the serogroups, polysaccharide composition and structures, biosynthetic loci and functions, biosynthesis pathways, and expression regulation mechanisms of the P. multocida capsule, supplying a theoretical basis for the molecular pathogenesis of the P. multocida capsule and the future development of capsular polysaccharide vaccines.
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21
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Characterization and Protective Activity of Monoclonal Antibodies Directed against Streptococcus suis Serotype 2 Capsular Polysaccharide Obtained Using a Glycoconjugate. Pathogens 2019; 8:pathogens8030139. [PMID: 31500262 PMCID: PMC6789524 DOI: 10.3390/pathogens8030139] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 08/29/2019] [Accepted: 09/03/2019] [Indexed: 02/06/2023] Open
Abstract
Streptococcus suis serotype 2 is an encapsulated bacterium and an important swine pathogen. Opsonizing antibody responses targeting capsular polysaccharides (CPSs) are protective against extracellular pathogens. To elucidate the protective activity of monoclonal antibodies (mAbs) directed against S. suis serotype 2 CPS, mice were immunized with a serotype 2 CPS-glycoconjugate and three hybridomas were isolated; of which, two were murine IgMs and the other a murine IgG1. Whereas the IgMs (mAbs 9E7 and 13C8) showed different reactivity levels with S. suis serotypes 1, 1/2, 2 and 14, the IgG1 (mAb 16H11) was shown to be serotype 2-specific. All mAbs targeted the sialylated chain of the CPSs. Using an opsonophagocytosis assay, the IgMs were opsonizing towards the S. suis serotypes to which they cross-react, while the IgG1 failed to induce bacterial elimination. In a model of mouse passive immunization followed by a lethal challenge with S. suis serotype 2, the IgG1 and IgM cross-reacting only with serotype 14 (mAb 13C8) failed to protect, while the IgM cross-reacting with serotypes 1, 1/2, and 14 (mAb 9E7) was shown to be protective by limiting bacteremia. These new mAbs show promise as new S. suis diagnostic tools, as well as potential for therapeutic applications.
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22
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Understanding the virulence of Streptococcus suis : A veterinary, medical, and economic challenge. Med Mal Infect 2018; 48:159-166. [DOI: 10.1016/j.medmal.2017.10.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 11/09/2016] [Accepted: 10/02/2017] [Indexed: 12/17/2022]
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23
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Auger JP, Chuzeville S, Roy D, Mathieu-Denoncourt A, Xu J, Grenier D, Gottschalk M. The bias of experimental design, including strain background, in the determination of critical Streptococcus suis serotype 2 virulence factors. PLoS One 2017; 12:e0181920. [PMID: 28753679 PMCID: PMC5533308 DOI: 10.1371/journal.pone.0181920] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 06/30/2017] [Indexed: 12/17/2022] Open
Abstract
Streptococcus suis serotype 2 is an important porcine bacterial pathogen and emerging zoonotic agent mainly responsible for sudden death, septic shock, and meningitis. However, serotype 2 strains are genotypically and phenotypically heterogeneous. Though a multitude of virulence factors have been described for S. suis serotype 2, the lack of a clear definition regarding which ones are truly “critical” has created inconsistencies that have only recently been highlighted. Herein, the involvement of two factors previously described as being critical for S. suis serotype 2 virulence, whether the dipeptidyl peptidase IV and autolysin, were evaluated with regards to different ascribed functions using prototype strains belonging to important sequence types. Results demonstrate a lack of reproducibility with previously published data. In fact, the role of the dipeptidyl peptidase IV and autolysin as critical virulence factors could not be confirmed. Though certain in vitro functions may be ascribed to these factors, their roles are not unique for S. suis, probably due to compensation by other factors. As such, variations and discrepancies in experimental design, including in vitro assays, cell lines, and animal models, are an important source of differences between results. Moreover, the use of different sequence types in this study demonstrates that the role attributed to a virulence factor may vary according to the S. suis serotype 2 strain background. Consequently, it is necessary to establish standard experimental designs according to the experiment and purpose in order to facilitate comparison between laboratories. Alongside, studies should include strains of diverse origins in order to prevent erroneous and biased conclusions that could affect future studies.
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Affiliation(s)
- Jean-Philippe Auger
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Sarah Chuzeville
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - David Roy
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Annabelle Mathieu-Denoncourt
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Jianguo Xu
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Daniel Grenier
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Oral Ecology Research Group (GREB), Faculty of Dentistry, Laval University, Quebec City, Quebec, Canada
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- Research Group on Infectious Diseases in Production Animals (GREMIP), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
- * E-mail:
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Calzas C, Taillardet M, Fourati IS, Roy D, Gottschalk M, Soudeyns H, Defrance T, Segura M. Evaluation of the Immunomodulatory Properties of Streptococcus suis and Group B Streptococcus Capsular Polysaccharides on the Humoral Response. Pathogens 2017; 6:pathogens6020016. [PMID: 28425925 PMCID: PMC5488650 DOI: 10.3390/pathogens6020016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/15/2017] [Accepted: 04/17/2017] [Indexed: 12/02/2022] Open
Abstract
Streptococcus suis and group B Streptococcus (GBS) are encapsulated streptococci causing septicemia and meningitis. Antibodies (Abs) against capsular polysaccharides (CPSs) have a crucial protective role, but the structure/composition of the CPS, including the presence of sialic acid, may interfere with the generation of anti-CPS Ab responses. We investigated the features of the CPS-specific Ab response directed against S. suis serotypes 2 and 14 and GBS serotypes III and V after infection or immunization with purified native or desialylated CPSs in mice. Whereas S. suis-infected mice developed a very low/undetectable CPS-specific IgM response, significant anti-CPS IgM titers were measured in GBS-infected animals (especially for type III GBS). No isotype switching was detected in S. suis- or GBS-infected mice. While the expression of sialic acid was essential for the immunogenicity of purified GBS type III CPS, this sugar was not responsible for the inability of purified S. suis types 2, 14 and GBS type V CPSs to induce a specific Ab response. Thus, other biochemical criteria unrelated to the presence of sialic acid may be responsible for the inaptitude of the host immune system to mount an effective response against certain S. suis and GBS CPS types.
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Affiliation(s)
- Cynthia Calzas
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
| | - Morgan Taillardet
- CIRI, INSERM, U1111, CNRS UMR5308, University of Lyon 1, 21 Avenue Tony Garnier, 69007 Lyon, France.
| | - Insaf Salem Fourati
- Department of Microbiology, Infectiology and Immunology, Faculty of Medicine, University of Montreal, C.P. 6128, Succ. Centre-ville, Montreal, QC H3C 3J7, Canada.
| | - David Roy
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
| | - Hugo Soudeyns
- Department of Microbiology, Infectiology and Immunology, Faculty of Medicine, University of Montreal, C.P. 6128, Succ. Centre-ville, Montreal, QC H3C 3J7, Canada.
| | - Thierry Defrance
- CIRI, INSERM, U1111, CNRS UMR5308, University of Lyon 1, 21 Avenue Tony Garnier, 69007 Lyon, France.
| | - Mariela Segura
- Swine and Poultry Infectious Diseases Research Center (CRIPA), Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
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25
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Porcine Dendritic Cells as an In Vitro Model to Assess the Immunological Behaviour of Streptococcus suis Subunit Vaccine Formulations and the Polarizing Effect of Adjuvants. Pathogens 2017; 6:pathogens6010013. [PMID: 28327531 PMCID: PMC5371901 DOI: 10.3390/pathogens6010013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/10/2017] [Accepted: 03/18/2017] [Indexed: 01/03/2023] Open
Abstract
An in vitro porcine bone marrow-derived dendritic cell (DC) culture was developed as a model for evaluating immune polarization induced by adjuvants when administered with immunogens that may become vaccine candidates if appropriately formulated. The swine pathogen Streptococcus suis was chosen as a prototype to evaluate proposed S. suis vaccine candidates in combination with the adjuvants Poly I:C, Quil A ®, Alhydrogel ®, TiterMax Gold ® and Stimune ®. The toll-like receptor ligand Poly I:C and the saponin Quil A ® polarized swine DC cytokines towards a type 1 phenotype, with preferential production of IL-12 and TNF-α. The water-in-oil adjuvants TiterMax Gold ® and Stimune ® favoured a type 2 profile as suggested by a marked IL-6 release. In contrast, Alhydrogel ® induced a type 1/type 2 mixed cytokine profile. The antigen type differently modified the magnitude of the adjuvant effect, but overall polarization was preserved. This is the first comparative report on swine DC immune activation by different adjuvants. Although further swine immunization studies would be required to better characterize the induced responses, the herein proposed in vitro model is a promising approach that helps assessing behaviour of the vaccine formulation rapidly at the pre-screening stage and will certainly reduce numbers of animals used while advancing vaccinology science.
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Hsueh KJ, Cheng LT, Lee JW, Chung YC, Chung WB, Chu CY. Immunization with Streptococcus suis bacterin plus recombinant Sao protein in sows conveys passive immunity to their piglets. BMC Vet Res 2017; 13:15. [PMID: 28061775 PMCID: PMC5219745 DOI: 10.1186/s12917-016-0937-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 12/22/2016] [Indexed: 11/24/2022] Open
Abstract
Background Streptococcus suis (S. suis) causes arthritis, meningitis, septicemia, and sudden death in pigs and is also an zoonotic agent for humans. The present study demonstrated that immunization with recombinant Sao-L (surface antigen one-L, rSao-L) protein from a strain of S. suis serotype 2 in pigs was able to increase cross-serotype protection against S. suis serotype 1 and 2 challenge. Since weaning piglets are more susceptible to S. suis infections due to the stresses associated with weaning, prepartum immunization in sows may convey passive immunity to piglets and provide protection. Results Pregnant sows were immunized with a vaccine containing inactivated S. suis serotype 2 plus rSao as the antigens. Blood samples were collected from their piglets after birth for analysis of antigen-specific antibody titers and levels of various cytokines. Results demonstrated that the titers of S. suis and rSao-specific antibodies were significantly (p < 0.05) higher in the vaccinated piglets in comparison with that of piglets in the control group. The serum levels of interferon (IFN)-γ, interleukin (IL)-4, IL-6, and IL-12 were significantly (p < 0.05) increased in piglets born from vaccinated sows when compared to piglets from unvaccinated sows. In addition, piglets were challenged by heterologous and homologous S. suis. All piglets from unvaccinated sows developed severe symptoms of bacteremia, fever, anorexia, depression, and arthritis. On the other hand, piglets from vaccinated sows had significantly (p < 0.05) reduced clinical symptoms and lesion score (by 75 and 81%). Conclusions Our results revealed that immunizing pregnant sows with the vaccine containing inactivated S. suis bacterin plus rSao as the antigens is able to enhance passive immunity against heterologous and homologous S. suis challenge in their piglets.
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Affiliation(s)
- Kai-Jen Hsueh
- Department of Veterinary medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.,Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuehfu Road, Neipu, Pingtung, 91201, Taiwan
| | - Li-Ting Cheng
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuehfu Road, Neipu, Pingtung, 91201, Taiwan
| | - Jai-Wei Lee
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Yao-Chi Chung
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuehfu Road, Neipu, Pingtung, 91201, Taiwan
| | - Wen-Bin Chung
- Department of Veterinary medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Chun-Yen Chu
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, 1, Shuehfu Road, Neipu, Pingtung, 91201, Taiwan.
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