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Da Costa RM, Rooke JL, Wells TJ, Cunningham AF, Henderson IR. Type 5 secretion system antigens as vaccines against Gram-negative bacterial infections. NPJ Vaccines 2024; 9:159. [PMID: 39218947 PMCID: PMC11366766 DOI: 10.1038/s41541-024-00953-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 08/14/2024] [Indexed: 09/04/2024] Open
Abstract
Infections caused by Gram-negative bacteria are leading causes of mortality worldwide. Due to the rise in antibiotic resistant strains, there is a desperate need for alternative strategies to control infections caused by these organisms. One such approach is the prevention of infection through vaccination. While live attenuated and heat-killed bacterial vaccines are effective, they can lead to adverse reactions. Newer vaccine technologies focus on utilizing polysaccharide or protein subunits for safer and more targeted vaccination approaches. One promising avenue in this regard is the use of proteins released by the Type 5 secretion system (T5SS). This system is the most prevalent secretion system in Gram-negative bacteria. These proteins are compelling vaccine candidates due to their demonstrated protective role in current licensed vaccines. Notably, Pertactin, FHA, and NadA are integral components of licensed vaccines designed to prevent infections caused by Bordetella pertussis or Neisseria meningitidis. In this review, we delve into the significance of incorporating T5SS proteins into licensed vaccines, their contributions to virulence, conserved structural motifs, and the protective immune responses elicited by these proteins.
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Affiliation(s)
- Rochelle M Da Costa
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Jessica L Rooke
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Timothy J Wells
- Frazer Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Adam F Cunningham
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Ian R Henderson
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia.
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2
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Pérez Jorge G, Gontijo M, Silva MFE, Goes ICRDS, Jaimes-Florez YP, Coser LDO, Rocha FJS, Giorgio S, Brocchi M. Attenuated mutants of Salmonella enterica Typhimurium mediate melanoma regression via an immune response. Exp Biol Med (Maywood) 2024; 249:10081. [PMID: 38974834 PMCID: PMC11224151 DOI: 10.3389/ebm.2024.10081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Accepted: 05/07/2024] [Indexed: 07/09/2024] Open
Abstract
The lack of effective treatment options for an increasing number of cancer cases highlights the need for new anticancer therapeutic strategies. Immunotherapy mediated by Salmonella enterica Typhimurium is a promising anticancer treatment. Candidate strains for anticancer therapy must be attenuated while retaining their antitumor activity. Here, we investigated the attenuation and antitumor efficacy of two S. enterica Typhimurium mutants, ΔtolRA and ΔihfABpmi, in a murine melanoma model. Results showed high attenuation of ΔtolRA in the Galleria mellonella model, and invasion and survival in tumor cells. However, it showed weak antitumor effects in vitro and in vivo. Contrastingly, lower attenuation of the attenuated ΔihfABpmi strain resulted in regression of tumor mass in all mice, approximately 6 days after the first treatment. The therapeutic response induced by ΔihfABpmi was accompanied with macrophage accumulation of antitumor phenotype (M1) and significant increase in the mRNAs of proinflammatory mediators (TNF-α, IL-6, and iNOS) and an apoptosis inducer (Bax). Our findings indicate that the attenuated ΔihfABpmi exerts its antitumor activity by inducing macrophage infiltration or reprogramming the immunosuppressed tumor microenvironment to an activated state, suggesting that attenuated S. enterica Typhimurium strains based on nucleoid-associated protein genes deletion could be immunotherapeutic against cancer.
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Affiliation(s)
- Genesy Pérez Jorge
- Departamento de Genética, Evolução, Microbiologia e Immunologia, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
- Research Group: Statistics and Mathematical Modeling Applied to Educational Quality, University of Sucre, Sincelejo, Sucre, Colombia
| | - Marco Gontijo
- Departamento de Genética, Evolução, Microbiologia e Immunologia, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Duke Medicine Cir, Durham, NC, United States
| | - Marina Flóro e Silva
- Departamento de Genética, Evolução, Microbiologia e Immunologia, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas—UNICAMP, Campinas, SP, Brazil
| | | | - Yessica Paola Jaimes-Florez
- Departamento de Genética, Evolução, Microbiologia e Immunologia, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
- GIMBIO Group, Department of Microbiology, Faculty of Basic Sciences, Universidad de Pamplona, Pamplona, Colombia
| | - Lilian de Oliveira Coser
- Departamento de Biologia Estrutural e Funcional, Laboratório de Regeneração Nervosa, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
| | - Francisca Janaína Soares Rocha
- Área Acadêmica de Medicina Tropical, Centro de Ciências Médicas, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Selma Giorgio
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas—UNICAMP, Campinas, SP, Brazil
| | - Marcelo Brocchi
- Departamento de Genética, Evolução, Microbiologia e Immunologia, Instituto de Biologia, Universidade Estadual de Campinas—UNICAMP, Campinas, SP, Brazil
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3
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Lu T, Das S, Howlader DR, Picking WD, Picking WL. Shigella Vaccines: The Continuing Unmet Challenge. Int J Mol Sci 2024; 25:4329. [PMID: 38673913 PMCID: PMC11050647 DOI: 10.3390/ijms25084329] [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: 02/27/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
Shigellosis is a severe gastrointestinal disease that annually affects approximately 270 million individuals globally. It has particularly high morbidity and mortality in low-income regions; however, it is not confined to these regions and occurs in high-income nations when conditions allow. The ill effects of shigellosis are at their highest in children ages 2 to 5, with survivors often exhibiting impaired growth due to infection-induced malnutrition. The escalating threat of antibiotic resistance further amplifies shigellosis as a serious public health concern. This review explores Shigella pathology, with a primary focus on the status of Shigella vaccine candidates. These candidates include killed whole-cells, live attenuated organisms, LPS-based, and subunit vaccines. The strengths and weaknesses of each vaccination strategy are considered. The discussion includes potential Shigella immunogens, such as LPS, conserved T3SS proteins, outer membrane proteins, diverse animal models used in Shigella vaccine research, and innovative vaccine development approaches. Additionally, this review addresses ongoing challenges that necessitate action toward advancing effective Shigella prevention and control measures.
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Affiliation(s)
- Ti Lu
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - Sayan Das
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA;
| | - Debaki R. Howlader
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - William D. Picking
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - Wendy L. Picking
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
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4
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Pastor Y, Calvo A, Salvador-Erro J, Gamazo C. Refining Immunogenicity through Intradermal Delivery of Outer Membrane Vesicles against Shigella flexneri in Mice. Int J Mol Sci 2023; 24:16910. [PMID: 38069232 PMCID: PMC10706920 DOI: 10.3390/ijms242316910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/23/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Shigellosis remains a global health concern, especially in low- and middle-income countries. Despite improvements in sanitation, the absence of a licensed vaccine for human use has prompted global health organizations to support the development of a safe and effective multivalent vaccine that is cost-effective and accessible for limited-resource regions. Outer Membrane Vesicles (OMVs) have emerged in recent years as an alternative to live attenuated or whole-inactivated vaccines due to their immunogenicity and self-adjuvating properties. Previous works have demonstrated the safety and protective capacity of OMVs against Shigella flexneri infection in mouse models when administered through mucosal or intradermal routes. However, some immunological properties, such as the cellular response or cross-protection among different Shigella strains, remained unexplored. In this study, we demonstrate that intradermal immunization of OMVs with needle-free devices recruits a high number of immune cells in the dermis, leading to a robust cellular response marked by antigen-specific cytokine release and activation of effector CD4 T cells. Additionally, functional antibodies are generated, neutralizing various Shigella serotypes, suggesting cross-protective capacity. These findings highlight the potential of OMVs as a promising vaccine platform against shigellosis and support intradermal administration as a simple and painless vaccination strategy to address this health challenge.
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Affiliation(s)
| | | | | | - Carlos Gamazo
- Department of Microbiology and Parasitology, Navarra Medical Research Institute (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (Y.P.); (A.C.); (J.S.-E.)
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5
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A Pentavalent Shigella flexneri LPS-Based Vaccine Candidate Is Safe and Immunogenic in Animal Models. Vaccines (Basel) 2023; 11:vaccines11020345. [PMID: 36851223 PMCID: PMC9966156 DOI: 10.3390/vaccines11020345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/19/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
A multivalent vaccine is much needed to achieve protection against predominant Shigella serotypes. Recently, we demonstrated the clinical applicability and immunogenic potential of tri-acylated S. flexneri 2a lipopolysaccharide (Ac3-S-LPS). Using a similar approach, we designed a pentavalent LPS candidate vaccine against S. flexneri 1b, 2a, 3a, 6, and Y (PLVF). In this study, we performed molecular and antigenic characterization of the vaccine candidate and its preclinical evaluation. There were no signs of acute toxicity after subcutaneous administration of PLVF in rabbits at a proposed human dose of 125 μg. No pyrogenic reactions and adverse effects associated with chronic toxicity after repeated administration of PLVF were revealed either. The immunization of mice with PLVF led to ≥16-fold increase in S. flexneri 1b-, 2a-, 3a-, 6-, and Y-specific antibodies. In a serum bactericidal antibody (SBA) assay, we registered 54%, 66%, 35%, 60%, and 60% killing of S. flexneri 1b, 2a, 3a, 6, and Y, respectively. In the guinea pig keratoconjunctivitis model, the efficacy was 50% to 75% against challenge with all five S. flexneri serotypes. These studies demonstrate that PLVF is safe, immunogenic over a wide range of doses, and provides protection against challenge with homologous S. flexneri strains, thus confirming the validity of pentavalent design of the combined vaccine.
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Pokharel P, Dhakal S, Dozois CM. The Diversity of Escherichia coli Pathotypes and Vaccination Strategies against This Versatile Bacterial Pathogen. Microorganisms 2023; 11:344. [PMID: 36838308 PMCID: PMC9965155 DOI: 10.3390/microorganisms11020344] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/03/2023] Open
Abstract
Escherichia coli (E. coli) is a gram-negative bacillus and resident of the normal intestinal microbiota. However, some E. coli strains can cause diseases in humans, other mammals and birds ranging from intestinal infections, for example, diarrhea and dysentery, to extraintestinal infections, such as urinary tract infections, respiratory tract infections, meningitis, and sepsis. In terms of morbidity and mortality, pathogenic E. coli has a great impact on public health, with an economic cost of several billion dollars annually worldwide. Antibiotics are not usually used as first-line treatment for diarrheal illness caused by E. coli and in the case of bloody diarrhea, antibiotics are avoided due to the increased risk of hemolytic uremic syndrome. On the other hand, extraintestinal infections are treated with various antibiotics depending on the site of infection and susceptibility testing. Several alarming papers concerning the rising antibiotic resistance rates in E. coli strains have been published. The silent pandemic of multidrug-resistant bacteria including pathogenic E. coli that have become more difficult to treat favored prophylactic approaches such as E. coli vaccines. This review provides an overview of the pathogenesis of different pathotypes of E. coli, the virulence factors involved and updates on the major aspects of vaccine development against different E. coli pathotypes.
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Affiliation(s)
- Pravil Pokharel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Sabin Dhakal
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Charles M. Dozois
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
- Pasteur Network, Laval, QC H7V 1B7, Canada
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7
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Lieberman LA. Outer membrane vesicles: A bacterial-derived vaccination system. Front Microbiol 2022; 13:1029146. [PMID: 36620013 PMCID: PMC9811673 DOI: 10.3389/fmicb.2022.1029146] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 12/01/2022] [Indexed: 12/24/2022] Open
Abstract
Outer membrane vesicles (OMVs) are non-living spherical nanostructures that derive from the cell envelope of Gram-negative bacteria. OMVs are important in bacterial pathogenesis, cell-to-cell communication, horizontal gene transfer, quorum sensing, and in maintaining bacterial fitness. These structures can be modified to express antigens of interest using glycoengineering and genetic or chemical modification. The resulting OMVs can be used to immunize individuals against the expressed homo- or heterologous antigens. Additionally, cargo can be loaded into OMVs and they could be used as a drug delivery system. OMVs are inherently immunogenic due to proteins and glycans found on Gram negative bacterial outer membranes. This review focuses on OMV manipulation to increase vesiculation and decrease antigenicity, their utility as vaccines, and novel engineering approaches to extend their application.
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8
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Zhang X, Sang S, Guan Q, Tao H, Wang Y, Liu C. Oral Administration of a Shigella 2aT32-Based Vaccine Expressing UreB-HspA Fusion Antigen With and Without Parenteral rUreB-HspA Boost Confers Protection Against Helicobacter pylori in Mice Model. Front Immunol 2022; 13:894206. [PMID: 35769459 PMCID: PMC9234132 DOI: 10.3389/fimmu.2022.894206] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Helicobacter pylori (H. pylori) is a gram-negative pathogen classified as a class I carcinogen. The H. pylori urease B subunit (UreB) and heat shock protein A (HspA) are two important vaccine candidate antigens. In this study, we evaluated the immunogenicity and immunoprotective effect of the attenuated Shigella vector vaccine SH02 expressing the UreB-HspA fusion protein of H. pylori in a mouse model. Oral SH02 with or without subcutaneous injection of rUreB-HspA induced antigen-specific serum IgG, mucosal sIgA, and T cells immune response. Subcutaneous injection of the candidate antigen rUreB-HspA enhanced the level of serum antigen-specific IgG antibodies (p < 0.0001) and the levels of IgG1/IgG2a/IgG2b subtypes. In addition, injection boost also increased the proportion of spleen antigen-specific CD4+CD154+ T cells (p < 0.001), and the proportion of CD4+CD154+ T cells that secrete IFN-γ and IL-17A. Following the H. pylori challenge, the levels of H. pylori colonization in the two experimental groups (Groups A and B) significantly reduced compared with the control group (p < 0.001), indicating that the candidate vaccine yielded a preventive effect of anti-H.pylori infection. Compared with the non-subcutaneous booster injection group (Group A), the subcutaneous booster injection group (Group B) exhibited less gastric inflammation, but there was no significant difference in the level of colonization (p > 0.05). These results lay a foundation for the development of a vaccine against H. pylori and the optimization of immunization methods and procedures to prevent H. pylori infection.
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Affiliation(s)
- Xin Zhang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
- Department of Pharmacy, Medical Supplies Center, Chinese People's Liberation Army General Hospital, Beijing, China
| | - Shuli Sang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
| | - Qing Guan
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
| | - Haoxia Tao
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
| | - Yanchun Wang
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
- *Correspondence: Chunjie Liu, ; Yanchun Wang,
| | - Chunjie Liu
- State Key Laboratory of Pathogen and Biosecurity, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China
- *Correspondence: Chunjie Liu, ; Yanchun Wang,
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9
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Roles of the Tol/Pal System in Bacterial Pathogenesis and Its Application to Antibacterial Therapy. Vaccines (Basel) 2022; 10:vaccines10030422. [PMID: 35335056 PMCID: PMC8953051 DOI: 10.3390/vaccines10030422] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 01/27/2023] Open
Abstract
The Tol/Pal system (also written as “The Tol-Pal system”) is a set of protein complexes produced by most Gram-negative bacteria. It comprises the inner membrane-associated and the outer membrane-anchored subunits composed of the TolA, TolQ, and TolR proteins and the TolB and Pal proteins, respectively. Although the Tol/Pal system was first defined as bacterial proteins involved in colicin uptake of Escherichia coli, its global roles have been characterized in several studies as mentioned in this article. Pathogenesis of many Gram-negative pathogens is sustained by the Tol/Pal system. It is also essential for cell growth and fitness in some pathogens. Therefore, the Tol/Pal system is proposed as a potential target for antimicrobial chemotherapy. Although the tol/pal mutants are low in virulence, they still have the ability to stimulate the immune system. The Pal protein is highly immunogenic and induces both adaptive and innate immune responses. Therefore, the tol/pal mutant strains and Pal proteins also have potential vaccine properties. For these reasons, the Tol/Pal system represents a promising research target in the development of antibacterial therapeutic strategies for refractory infections caused by multi-drug-resistant (MDR), Gram-negative pathogens. In this paper, we summarize studies on the Tol/Pal system associated with bacterial pathogenesis and vaccine development.
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Shigella Outer Membrane Vesicles as Promising Targets for Vaccination. Int J Mol Sci 2022; 23:ijms23020994. [PMID: 35055181 PMCID: PMC8781765 DOI: 10.3390/ijms23020994] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 12/17/2022] Open
Abstract
The clinical symptoms of shigellosis, a gastrointestinal infection caused by Shigella spp. range from watery diarrhea to fulminant dysentery. Endemic infections, particularly among children in developing countries, represent the majority of clinical cases. The situation is aggravated due to the high mortality rate of shigellosis, the rapid dissemination of multi-resistant Shigella strains and the induction of only serotype-specific immunity. Thus, infection prevention due to vaccination, encompassing as many of the circulating serotypes as possible, has become a topic of interest. However, vaccines have turned out to be ineffective so far. Outer membrane vesicles (OMVs) are promising novel targets for vaccination. OMVs are constitutively secreted by Gram-negative bacteria including Shigella during growth. They are composed of soluble luminal portions and an insoluble membrane and can contain toxins, bioactive periplasmic and cytoplasmic (lipo-) proteins, (phospho-) lipids, nucleic acids and/or lipopolysaccharides. Thus, OMVs play an important role in bacterial cell–cell communication, growth, survival and pathogenesis. Furthermore, they modulate the secretion and transport of biomolecules, the stress response, antibiotic resistance and immune responses of the host. Thus, OMVs serve as novel secretion machinery. Here, we discuss the current literature and highlight the properties of OMVs as potent vaccine candidates because of their immunomodulatory, antigenic and adjuvant properties.
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11
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Marchant P, Carreño A, Vivanco E, Silva A, Nevermann J, Otero C, Araya E, Gil F, Calderón IL, Fuentes JA. "One for All": Functional Transfer of OMV-Mediated Polymyxin B Resistance From Salmonella enterica sv. Typhi Δ tolR and Δ degS to Susceptible Bacteria. Front Microbiol 2021; 12:672467. [PMID: 34025627 PMCID: PMC8131662 DOI: 10.3389/fmicb.2021.672467] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/12/2021] [Indexed: 12/22/2022] Open
Abstract
The appearance of multi-resistant strains has contributed to reintroducing polymyxin as the last-line therapy. Although polymyxin resistance is based on bacterial envelope changes, other resistance mechanisms are being reported. Outer membrane vesicles (OMVs) are nanosized proteoliposomes secreted from the outer membrane of Gram-negative bacteria. In some bacteria, OMVs have shown to provide resistance to diverse antimicrobial agents either by sequestering and/or expelling the harmful agent from the bacterial envelope. Nevertheless, the participation of OMVs in polymyxin resistance has not yet been explored in S. Typhi, and neither OMVs derived from hypervesiculating mutants. In this work, we explored whether OMVs produced by the hypervesiculating strains Salmonella Typhi ΔrfaE (LPS synthesis), ΔtolR (bacterial envelope) and ΔdegS (misfolded proteins and σ E activation) exhibit protective properties against polymyxin B. We found that the OMVs extracted from S. Typhi ΔtolR and ΔdegS protect S. Typhi WT from polymyxin B in a concentration-depending manner. By contrast, the protective effect exerted by OMVs from S. Typhi WT and S. Typhi ΔrfaE is much lower. This effect is achieved by the sequestration of polymyxin B, as assessed by the more positive Zeta potential of OMVs with polymyxin B and the diminished antibiotic's availability when coincubated with OMVs. We also found that S. Typhi ΔtolR exhibited an increased MIC of polymyxin B. Finally, we determined that S. Typhi ΔtolR and S. Typhi ΔdegS, at a lesser level, can functionally and transiently transfer the OMV-mediated polymyxin B resistance to susceptible bacteria in cocultures. This work shows that mutants in genes related to OMVs biogenesis can release vesicles with improved abilities to protect bacteria against membrane-active agents. Since mutations affecting OMV biogenesis can involve the bacterial envelope, mutants with increased resistance to membrane-acting agents that, in turn, produce protective OMVs with a high vesiculation rate (e.g., S. Typhi ΔtolR) can arise. Such mutants can functionally transfer the resistance to surrounding bacteria via OMVs, diminishing the effective concentration of the antimicrobial agent and potentially favoring the selection of spontaneous resistant strains in the environment. This phenomenon might be considered the source for the emergence of polymyxin resistance in an entire bacterial community.
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Affiliation(s)
- Pedro Marchant
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Alexander Carreño
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Eduardo Vivanco
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Andrés Silva
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Jan Nevermann
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Carolina Otero
- Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile
| | - Eyleen Araya
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Santiago, Chile
| | - Fernando Gil
- Microbiota-Host Interactions and Clostridia Research Group, Universidad Andres Bello, Santiago, Chile.,ANID-Millennium Science Initiative Program-Millennium Nucleus in the Biology of the Intestinal Microbiota, Santiago, Chile
| | - Iván L Calderón
- Laboratorio de RNAs Bacterianos, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Juan A Fuentes
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
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12
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Bazhenova A, Gao F, Bolgiano B, Harding SE. Glycoconjugate vaccines against Salmonella enterica serovars and Shigella species: existing and emerging methods for their analysis. Biophys Rev 2021; 13:221-246. [PMID: 33868505 PMCID: PMC8035613 DOI: 10.1007/s12551-021-00791-z] [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: 11/12/2020] [Accepted: 02/25/2021] [Indexed: 12/26/2022] Open
Abstract
The global spread of enteric disease, the increasingly limited options for antimicrobial treatment and the need for effective eradication programs have resulted in an increased demand for glycoconjugate enteric vaccines, made with carbohydrate-based membrane components of the pathogen, and their precise characterisation. A set of physico-chemical and immunological tests are employed for complete vaccine characterisation and to ensure their consistency, potency, safety and stability, following the relevant World Health Organization and Pharmacopoeia guidelines. Variable requirements for analytical methods are linked to conjugate structure, carrier protein nature and size and O-acetyl content of polysaccharide. We investigated a key stability-indicating method which measures the percent free saccharide of Salmonella enterica subspecies enterica serovar Typhi capsular polysaccharide, by detergent precipitation, depolymerisation and HPAEC-PAD quantitation. Together with modern computational approaches, a more precise design of glycoconjugates is possible, allowing for improvements in solubility, structural conformation and stability, and immunogenicity of antigens, which may be applicable to a broad spectrum of vaccines. More validation experiments are required to establish the most effective and suitable methods for glycoconjugate analysis to bring uniformity to the existing protocols, although the need for product-specific approaches will apply, especially for the more complex vaccines. An overview of current and emerging analytical approaches for the characterisation of vaccines against Salmonella Typhi and Shigella species is described in this paper. This study should aid the development and licensing of new glycoconjugate vaccines aimed at the prevention of enteric diseases.
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Affiliation(s)
- Aleksandra Bazhenova
- School of Biosciences, University of Nottingham, Sutton Bonington, Loughborough, LE12 5RD UK
| | - Fang Gao
- Division of Bacteriology, National Institute for Biological Standards and Control (NIBSC), Blanche Lane, South Mimms, Potters Bar, EN6 3QG UK
| | - Barbara Bolgiano
- Division of Bacteriology, National Institute for Biological Standards and Control (NIBSC), Blanche Lane, South Mimms, Potters Bar, EN6 3QG UK
| | - Stephen E. Harding
- School of Biosciences, University of Nottingham, Sutton Bonington, Loughborough, LE12 5RD UK
- Museum of Cultural History, University of Oslo, Postboks 6762 St. Olavs plass, 0130 Oslo, Norway
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13
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Szczepaniak J, Press C, Kleanthous C. The multifarious roles of Tol-Pal in Gram-negative bacteria. FEMS Microbiol Rev 2021; 44:490-506. [PMID: 32472934 PMCID: PMC7391070 DOI: 10.1093/femsre/fuaa018] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/28/2020] [Indexed: 12/15/2022] Open
Abstract
In the 1960s several groups reported the isolation and preliminary genetic mapping of
Escherichia coli strains tolerant towards the
action of colicins. These pioneering studies kick-started two new fields in bacteriology;
one centred on how bacteriocins like colicins exploit the Tol (or more commonly Tol-Pal)
system to kill bacteria, the other on the physiological role of this cell
envelope-spanning assembly. The following half century has seen significant advances in
the first of these fields whereas the second has remained elusive, until recently. Here,
we review work that begins to shed light on Tol-Pal function in Gram-negative bacteria.
What emerges from these studies is that Tol-Pal is an energised system with fundamental,
interlinked roles in cell division – coordinating the re-structuring of peptidoglycan at
division sites and stabilising the connection between the outer membrane and underlying
cell wall. This latter role is achieved by Tol-Pal exploiting the proton motive force to
catalyse the accumulation of the outer membrane peptidoglycan associated lipoprotein Pal
at division sites while simultaneously mobilising Pal molecules from around the cell.
These studies begin to explain the diverse phenotypic outcomes of tol-pal
mutations, point to other cell envelope roles Tol-Pal may have and raise many new
questions.
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Affiliation(s)
- Joanna Szczepaniak
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
| | - Cara Press
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
| | - Colin Kleanthous
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford OX1 3QU, UK
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14
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Multilamellar and Multivesicular Outer Membrane Vesicles Produced by a Buttiauxella agrestis tolB Mutant. Appl Environ Microbiol 2020; 86:AEM.01131-20. [PMID: 32801184 DOI: 10.1128/aem.01131-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/13/2020] [Indexed: 12/14/2022] Open
Abstract
Outer membrane vesicles (OMVs) are naturally released from Gram-negative bacteria and play important roles in various biological functions. Released vesicles are not uniform in shape, size, or characteristics, and little is known about this diversity of OMVs. Here, we show that deletion of tolB, which encodes a part of the Tol-Pal system, leads to the production of multiple types of vesicles and increases overall vesicle production in the high-vesicle-forming Buttiauxella agrestis type strain JCM 1090. The ΔtolB mutant produced small OMVs and multilamellar/multivesicular OMVs (M-OMVs) as well as vesicles with a striking similarity to the wild type. M-OMVs, previously undescribed, contained triple-lamellar membrane vesicles and multiple vesicle-incorporating vesicles. Ultracentrifugation enabled the separation and purification of each type of OMV released from the ΔtolB mutant, and visualization by quick-freeze deep-etch and replica electron microscopy indicated that M-OMVs are composed of several lamellar membranes. Visualization of intracellular compartments of ΔtolB mutant cells showed that vesicles were accumulated in the broad periplasm, which is probably due to the low linkage between the outer and inner membranes attributed to the Tol-Pal defect. The outer membrane was invaginating inward by wrapping a vesicle, and the precursor of M-OMVs existed in the cell. Thus, we demonstrated a novel type of bacterial OMV and showed that unconventional processes enable the B. agrestis ΔtolB mutant to form unique vesicles.IMPORTANCE Membrane vesicle (MV) formation has been recognized as a common mechanism in prokaryotes, and MVs play critical roles in intercellular interaction. However, a broad range of MV types and their multiple production processes make it difficult to gain a comprehensive understanding of MVs. In this work, using vesicle separation and electron microscopic analyses, we demonstrated that diverse types of outer membrane vesicles (OMVs) were released from an engineered strain, Buttiauxella agrestis JCM 1090T ΔtolB mutant. We also discovered a previously undiscovered type of vesicle, multilamellar/multivesicular outer membrane vesicles (M-OMVs), which were released by this mutant using unconventional processes. These findings have facilitated considerable progress in understanding MV diversity and expanding the utility of MVs in biotechnological applications.
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15
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Piccini G, Montomoli E. Pathogenic signature of invasive non-typhoidal Salmonella in Africa: implications for vaccine development. Hum Vaccin Immunother 2020; 16:2056-2071. [PMID: 32692622 PMCID: PMC7553687 DOI: 10.1080/21645515.2020.1785791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Invasive non-typhoidal Salmonella (iNTS) infections are a leading cause of bacteremia in Sub-Saharan Africa (sSA), thereby representing a major public health threat. Salmonella Typhimurium clade ST313 and Salmonella Enteriditis lineages associated with Western and Central/Eastern Africa are among the iNTS serovars which are of the greatest concern due to their case-fatality rate, especially in children and in the immunocompromised population. Identification of pathogen-associated features and host susceptibility factors that increase the risk for invasive non-typhoidal salmonellosis would be instrumental for the design of targeted prevention strategies, which are urgently needed given the increasing spread of multidrug-resistant iNTS in Africa. This review summarizes current knowledge of bacterial traits and host immune responses associated with iNTS infections in sSA, then discusses how this knowledge can guide vaccine development while providing a summary of vaccine candidates in preclinical and early clinical development.
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Affiliation(s)
| | - Emanuele Montomoli
- VisMederi srl , Siena, Italy.,Department of Molecular and Developmental Medicine, University of Siena , Siena, Italy
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16
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Pastor Y, Ting I, Martínez AL, Irache JM, Gamazo C. Intranasal delivery system of bacterial antigen using thermosensitive hydrogels based on a Pluronic-Gantrez conjugate. Int J Pharm 2020; 579:119154. [PMID: 32081801 DOI: 10.1016/j.ijpharm.2020.119154] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/12/2020] [Accepted: 02/15/2020] [Indexed: 02/07/2023]
Abstract
Thermosensitive hydrogels have been studied as feasible needle-avoidance alternative to vaccine delivery. In this work, we report the development of a new thermal-sensitive hydrogel for intranasal vaccine delivery. This delivery system was formulated with a combination of the polymer Gantrez® AN119 and the surfactant Pluronic® F127 (PF127), with a high biocompatibility, biodegradability and immunoadjuvant properties. Shigella flexneri outer membrane vesicles were used as the antigen model. A stable and easy-to-produce thermosensitive hydrogel which allowed the incorporation of the OMV-antigenic complex was successfully synthetized. A rapid gel formation was achieved at body temperature, which prolonged the OMV-antigens residence time in the nasal cavity of BALB/c mice when compared to intranasal delivery of free-OMVs. In addition, the bacterial antigens showed a fast release profile from the hydrogel in vitro, with a peak at 30 min of incubation at 37 °C. Hydrogels appeared to be non-cytotoxic in the human epithelial HeLa cell line and nose epithelium as well, as indicated by the absence of histopathological features. Immunohistochemical studies revealed that after intranasal administration the OMVs reached the nasal associated lymphoid tissue. These results support the use of here described thermosensitive hydrogels as a potential platform for intranasal vaccination.
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Affiliation(s)
- Yadira Pastor
- Department of Microbiology and Parasitology, Institute of Tropical Health University of Navarra, 31008 Pamplona, Spain
| | - Isaiah Ting
- Department of Microbiology and Parasitology, Institute of Tropical Health University of Navarra, 31008 Pamplona, Spain
| | - Ana Luisa Martínez
- Department of Technology and Pharmaceutical Chemistry, University of Navarra, Spain
| | - Juan Manuel Irache
- Department of Technology and Pharmaceutical Chemistry, University of Navarra, Spain
| | - Carlos Gamazo
- Department of Microbiology and Parasitology, Institute of Tropical Health University of Navarra, 31008 Pamplona, Spain.
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Dissolving Microneedles for Intradermal Vaccination against Shigellosis. Vaccines (Basel) 2019; 7:vaccines7040159. [PMID: 31653077 PMCID: PMC6963400 DOI: 10.3390/vaccines7040159] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/22/2019] [Accepted: 10/22/2019] [Indexed: 12/22/2022] Open
Abstract
Intradermal (ID) immunization is of increasing interest due to the easy accessibility and excellent immunogenic properties of the skin. Among ID immunization methods, dissolving microneedles (MNs) have appeared as an alternative to traditional hypodermic immunization, offering many advantages, such as being an easily administered method, with no need for health personnel, painless, and avoiding the use of needles and sharp wastage. In this study, an affordable and easy-to-produce MNs method was developed based on aqueous blends of 30% w/w poly (methyl vinyl ether-co-maleic anhydride). As an antigen model, a subunit vaccine candidate based on outer membrane vesicles from Shigella flexneri was used. Both unloaded and antigen-loaded MNs were synthetized and characterized. The MNs were successfully validated in an in vitro Parafilm M® skin model and in a pig skin ex vivo model. Biodistribution studies were performed in BALB/c mice using 99mTcO4− radiolabeled samples. Results indicated that the vesicle vaccine was successfully released from the MNs and targeted gastrointestinal tract after 6 h post-administration. In vivo immunization and protection studies were performed in BALB/c mice. Mice were intradermally immunized through ear skin with one single dose of 200 μg antigenic complex, eliciting the production of specific systemic IgG and mucosal IgA. Moreover, MNs were able to protect mice from an experimental infection with 1×106 CFU/mouse of S. flexneri four weeks after immunization. This work demonstrates for the first time the potential of outer membrane vesicle-loaded dissolving MNs for ID vaccination against enteropathogens like Shigella.
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