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Kapulu MC, Muthumbi E, Otieno E, Rossi O, Ferruzzi P, Necchi F, Acquaviva A, Martin LB, Orindi B, Mwai K, Kibet H, Mwanzu A, Bigogo GM, Verani JR, Mbae C, Nyundo C, Agoti CN, Nakakana UN, Conti V, Bejon P, Kariuki S, Scott JAG, Micoli F, Podda A. Age-dependent acquisition of IgG antibodies to Shigella serotypes-a retrospective analysis of seroprevalence in Kenyan children with implications for infant vaccination. Front Immunol 2024; 15:1340425. [PMID: 38361949 PMCID: PMC10867106 DOI: 10.3389/fimmu.2024.1340425] [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: 11/20/2023] [Accepted: 01/12/2024] [Indexed: 02/17/2024] Open
Abstract
Background Shigellosis mainly affects children under 5 years of age living in low- and middle-income countries, who are the target population for vaccination. There are, however, limited data available to define the appropriate timing for vaccine administration in this age group. Information on antibody responses following natural infection, proxy for exposure, could help guide vaccination strategies. Methods We undertook a retrospective analysis of antibodies to five of the most prevalent Shigella serotypes among children aged <5 years in Kenya. Serum samples from a cross-sectional serosurvey in three Kenyan sites (Nairobi, Siaya, and Kilifi) were analyzed by standardized ELISA to measure IgG against Shigella sonnei and Shigella flexneri 1b, 2a, 3a, and 6. We identified factors associated with seropositivity to each Shigella serotype, including seropositivity to other Shigella serotypes. Results A total of 474 samples, one for each participant, were analyzed: Nairobi (n = 169), Siaya (n = 185), and Kilifi (n = 120). The median age of the participants was 13.4 months (IQR 7.0-35.6), and the male:female ratio was 1:1. Geometric mean concentrations (GMCs) for each serotype increased with age, mostly in the second year of life. The overall seroprevalence of IgG antibodies increased with age except for S. flexneri 6 which was high across all age subgroups. In the second year of life, there was a statistically significant increase of antibody GMCs against all five serotypes (p = 0.01-0.0001) and a significant increase of seroprevalence for S. flexneri 2a (p = 0.006), S. flexneri 3a (p = 0.006), and S. sonnei (p = 0.05) compared with the second part of the first year of life. Among all possible pairwise comparisons of antibody seropositivity, there was a significant association between S. flexneri 1b and 2a (OR = 6.75, 95% CI 3-14, p < 0.001) and between S. flexneri 1b and 3a (OR = 23.85, 95% CI 11-54, p < 0.001). Conclusion Children living in low- and middle-income settings such as Kenya are exposed to Shigella infection starting from the first year of life and acquire serotype-specific antibodies against multiple serotypes. The data from this study suggest that Shigella vaccination should be targeted to infants, ideally at 6 or at least 9 months of age, to ensure children are protected in the second year of life when exposure significantly increases.
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Affiliation(s)
- Melissa C. Kapulu
- KEMRI-Wellcome Trust Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Esther Muthumbi
- KEMRI-Wellcome Trust Programme, Kilifi, Kenya
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Omar Rossi
- GSK Vaccines Institute for Global Health, Siena, Italy
| | | | | | | | | | | | - Kennedy Mwai
- KEMRI-Wellcome Trust Programme, Kilifi, Kenya
- Epidemiology and Biostatistics Division, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | | | | | - Godfrey M. Bigogo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Jennifer R. Verani
- Division of Global Health Protection, US Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Cecilia Mbae
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | | | | | | | | | - Philip Bejon
- KEMRI-Wellcome Trust Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - J. Anthony G. Scott
- KEMRI-Wellcome Trust Programme, Kilifi, Kenya
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Audino Podda
- GSK Vaccines Institute for Global Health, Siena, Italy
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Shrivastava S, Agnememel AB, Ndungo E, Islam D, Liang Y, Frenck RW, Pasetti MF. Oral immunization with Shigella sonnei WRSs2 and WRSs3 vaccine strains elicits systemic and mucosal antibodies with functional anti-microbial activity. mSphere 2024; 9:e0041923. [PMID: 38132716 PMCID: PMC10826362 DOI: 10.1128/msphere.00419-23] [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: 07/26/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
Shigella causes bacillary dysentery and is responsible for a high burden of disease globally. Several studies have emphasized the value of functional antibody activity to understand Shigella immunity and correlates of protection. The anti-microbial function of local (mucosal) antibodies and their contribution to preventing Shigella infection remain unknown. The goal of this study was to identify the functional humoral immune effectors elicited by two Shigella sonnei live oral vaccine candidates, WRSs2 and WRSs3. Complement-dependent bactericidal [serum bactericidal antibody (SBA)/bactericidal antibody (BA)] and opsonophagocytic killing antibody (OPKA) activity were determined in sera and stool extracts as indicators of systemic and local anti-microbial immunity. High levels of SBA/BA and OPKA were detected in serum as well as in fecal extracts from volunteers who received a single dose of WRSs2 and WRSs3. Functional antibody activity peaked on days 10 and 14 post-vaccination in fecal and serum samples, respectively. Bactericidal and OPKA titers were closely associated. Peak fold rises in functional antibody titers in serum and fecal extracts were also associated. Antibody activity interrogated in IgG and IgA purified from stool fractions identified IgG as the primary driver of mucosal bactericidal and OPKA activity, with minimal functional activity of IgA alone, highlighting an underappreciated role for IgG in bacterial clearance in the mucosa. The combination of IgG and IgA in equal proportions enhanced bactericidal and OPKA titers hinting at a co-operative or synergistic action. Our findings provide insight into the functional anti-microbial capacity of vaccine-induced mucosal IgG and IgA and propose an operative local humoral effector of protective immunity.IMPORTANCEThere is an urgent need for a safe, effective, and affordable vaccine against Shigella. Understanding the immunological underpinning of Shigella infection and the make-up of protective immunity is critical to achieve the best approach to prevent illness caused by this mucosal pathogen. We measured the complement-dependent bactericidal and opsonophagocytic antibody killing in serum and stool extracts from adult volunteers vaccinated with Shigella sonnei live oral vaccine candidates WRSs2 and WRSs3. For the first time, we detected functional antibody responses in stool samples that were correlated with those in sera. Using purified stool IgA and IgG fractions, we found that functional activity was mediated by IgG, with some help from IgA. These findings provide insight into the functional anti-microbial capacity of vaccine-induced mucosal IgG and IgA and support future studies to identify potential markers of protective mucosal immunity.
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Affiliation(s)
- Shikha Shrivastava
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Alain B. Agnememel
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Esther Ndungo
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dilara Islam
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Yuanyuan Liang
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Robert W. Frenck
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Marcela F. Pasetti
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Kelly M, Mandlik A, Charles RC, Verma S, Calderwood SB, Leung DT, Biswas R, Islam K, Kamruzzaman M, Chowdhury F, Khanam F, Vann WF, Khan AI, Bhuiyan TR, Qadri F, Vortherms AR, Kaminski R, Kováč P, Xu P, Ryan ET. Development of Shigella conjugate vaccines targeting Shigella flexneri 2a and S. flexneri 3a using a simple platform-approach conjugation by squaric acid chemistry. Vaccine 2023; 41:4967-4977. [PMID: 37400283 PMCID: PMC10529421 DOI: 10.1016/j.vaccine.2023.06.052] [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: 01/30/2023] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 07/05/2023]
Abstract
There is a need for vaccines effective against shigella infection in young children in resource-limited areas. Protective immunity against shigella infection targets the O-specific polysaccharide (OSP) component of lipopolysaccharide. Inducing immune responses to polysaccharides in young children can be problematic, but high level and durable responses can be induced by presenting polysaccharides conjugated to carrier proteins. An effective shigella vaccine will need to be multivalent, targeting the most common global species and serotypes such as Shigella flexneri 2a, S. flexneri 3a, S. flexneri 6, and S. sonnei. Here we report the development of shigella conjugate vaccines (SCV) targeting S. flexneri 2a (SCV-Sf2a) and 3a (SCV-Sf3a) using squaric acid chemistry to result in single point sun-burst type display of OSP from carrier protein rTTHc, a 52 kDa recombinant protein fragment of the heavy chain of tetanus toxoid. We confirmed structure and demonstrated that these conjugates were recognized by serotype-specific monoclonal antibodies and convalescent sera of humans recovering from shigellosis in Bangladesh, suggesting correct immunological display of OSP. We vaccinated mice and found induction of serotype-specific OSP and LPS IgG responses, as well as rTTHc-specific IgG responses. Vaccination induced serotype-specific bactericidal antibody responses against S. flexneri, and vaccinated animals were protected against keratoconjunctivitis (Sereny test) and intraperitoneal challenge with virulent S. flexneri 2a and 3a, respectively. Our results support further development of this platform conjugation technology in the development of shigella conjugate vaccines for use in resource-limited settings.
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Affiliation(s)
- Meagan Kelly
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
| | - Anjali Mandlik
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
| | - Richelle C Charles
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA; Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Smriti Verma
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
| | - Stephen B Calderwood
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Daniel T Leung
- Division of Infectious Diseases, University of Utah, Salt Lake City, Utah, USA
| | - Rajib Biswas
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Kamrul Islam
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Mohammad Kamruzzaman
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Fahima Chowdhury
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Farhana Khanam
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Willie F Vann
- Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Ashraful Islam Khan
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Taufiqur Rahman Bhuiyan
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Firdausi Qadri
- icddr,b (International Centre for Diarrhoeal Disease Research, Bangladesh), Dhaka, Bangladesh
| | - Anthony R Vortherms
- Department of Diarrheal Disease Research, Bacterial Diseases Branch, Walter Reed Army Institute of Research, Bethesda, MD, USA
| | - Robert Kaminski
- Department of Diarrheal Disease Research, Bacterial Diseases Branch, Walter Reed Army Institute of Research, Bethesda, MD, USA
| | - Pavol Kováč
- NIDDK, LBC, National Institutes of Health, Bethesda, MD, USA
| | - Peng Xu
- NIDDK, LBC, National Institutes of Health, Bethesda, MD, USA
| | - Edward T Ryan
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA; Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
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Ndungo E, Holm JB, Gama S, Buchwald AG, Tennant SM, Laufer MK, Pasetti MF, Rasko DA. Dynamics of the Gut Microbiome in Shigella-Infected Children during the First Two Years of Life. mSystems 2022; 7:e0044222. [PMID: 36121169 PMCID: PMC9600951 DOI: 10.1128/msystems.00442-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/23/2022] [Indexed: 02/02/2023] Open
Abstract
Shigella continues to be a major contributor to diarrheal illness and dysentery in children younger than 5 years of age in low- and middle-income countries. Strategies for the prevention of shigellosis have focused on enhancing adaptive immunity. The interaction between Shigella and intrinsic host factors, such as the microbiome, remains unknown. We hypothesized that Shigella infection would impact the developing microbial community in infancy and, conversely, that changes in the gastrointestinal microbiome may predispose infections. To test this hypothesis, we characterized the gastrointestinal microbiota in a longitudinal birth cohort from Malawi that was monitored for Shigella infection using 16S rRNA amplicon sequencing. Children with at least one Shigella quantitative polymerase chain reaction (qPCR) positive sample during the first 2 years of life (cases) were compared to uninfected controls that were matched for sex and age. Overall, the microbial species diversity, as measured by the Shannon diversity index, increased over time, regardless of case status. At early time points, the microbial community was dominated by Bifidobacterium longum and Escherichia/Shigella. A greater abundance of Prevotella 9 and Bifidobacterium kashiwanohense was observed at 2 years of age. While no single species was associated with susceptibility to Shigella infection, significant increases in Lachnospiraceae NK4A136 and Fusicatenibacter saccharivorans were observed following Shigella infection. Both taxa are in the family Lachnospiraceae, which are known short-chain fatty acid producers that may improve gut health. Our findings identified temporal changes in the gastrointestinal microbiota associated with Shigella infection in Malawian children and highlight the need to further elucidate the microbial communities associated with disease susceptibility and resolution. IMPORTANCE Shigella causes more than 180 million cases of diarrhea globally, mostly in children living in poor regions. Infection can lead to severe health impairments that reduce quality of life. There is increasing evidence that disruptions in the gut microbiome early in life can influence susceptibility to illnesses. A delayed or impaired reconstitution of the microbiota following infection can further impact overall health. Aiming to improve our understanding of the interaction between Shigella and the developing infant microbiome, we investigated changes in the gut microbiome of Shigella-infected and uninfected children over the course of their first 2 years of life. We identified species that may be involved in recovery from Shigella infection and in driving the microbiota back to homeostasis. These findings support future studies into the elucidation of the interaction between the microbiota and enteric pathogens in young children and into the identification of potential targets for prevention or treatment.
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Affiliation(s)
- Esther Ndungo
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Johanna B. Holm
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Syze Gama
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Andrea G. Buchwald
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Sharon M. Tennant
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Miriam K. Laufer
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Marcela F. Pasetti
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - David A. Rasko
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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5
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Mucosal Immune Profiles Associated with Diarrheal Disease Severity in Shigella- and Enteropathogenic Escherichia coli-Infected Children Enrolled in the Global Enteric Multicenter Study. mBio 2022; 13:e0053822. [PMID: 35924851 PMCID: PMC9426439 DOI: 10.1128/mbio.00538-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) and Shigella are etiologic agents of diarrhea in children <5 years old living in resource-poor countries. Repeated bouts of infection lead to lifelong morbidity and even death. The goal of this study was to characterize local mucosal immune responses in Shigella- and EPEC-infected children <5 years of age with moderate to severe diarrhea (MSD) enrolled in the Global Enteric Multicenter Study (GEMS). We hypothesized that infection with each of these pathogens would induce distinct gut mucosal immune profiles indicative of disease etiology and severity. To test this hypothesis, innate and adaptive immune markers were measured in stools from children with diarrhea due to EPEC, Shigella, or other organisms and in children who had no diarrhea. Shigella-positive diarrhea evoked robust proinflammatory and TH1/TH2 cytokine responses compared to diarrhea caused by EPEC or other organisms, with the exception of interleukin 5 (IL-5), which was associated with EPEC infection. The presence of IL-1β, IL-4, IL-16, and tumor necrosis factor beta (TNF-β) was associated with the absence of dysentery. EPEC-positive diarrhea evoked high levels of IL-1β, vascular endothelial growth factor (VEGF), and IL-10. Granulocyte-macrophage colony-stimulating factor (GM-CSF) had opposing roles in disease severity, being associated with absence of diarrhea in EPEC-infected children and with dysenteric Shigella infection. High levels of antigen-specific antibodies were detected in the controls and children with Shigella without dysentery, which suggests a protective role against severe disease. In summary, this study identified distinct local immune responses associated with two clinically relevant diarrheagenic pathogens, Shigella and EPEC, in children and identified protective immune phenotypes that can inform the development of preventive measures.
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Mechanical Forces Govern Interactions of Host Cells with Intracellular Bacterial Pathogens. Microbiol Mol Biol Rev 2022; 86:e0009420. [PMID: 35285720 PMCID: PMC9199418 DOI: 10.1128/mmbr.00094-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To combat infectious diseases, it is important to understand how host cells interact with bacterial pathogens. Signals conveyed from pathogen to host, and vice versa, may be either chemical or mechanical. While the molecular and biochemical basis of host-pathogen interactions has been extensively explored, relatively less is known about mechanical signals and responses in the context of those interactions. Nevertheless, a wide variety of bacterial pathogens appear to have developed mechanisms to alter the cellular biomechanics of their hosts in order to promote their survival and dissemination, and in turn many host responses to infection rely on mechanical alterations in host cells and tissues to limit the spread of infection. In this review, we present recent findings on how mechanical forces generated by host cells can promote or obstruct the dissemination of intracellular bacterial pathogens. In addition, we discuss how in vivo extracellular mechanical signals influence interactions between host cells and intracellular bacterial pathogens. Examples of such signals include shear stresses caused by fluid flow over the surface of cells and variable stiffness of the extracellular matrix on which cells are anchored. We highlight bioengineering-inspired tools and techniques that can be used to measure host cell mechanics during infection. These allow for the interrogation of how mechanical signals can modulate infection alongside biochemical signals. We hope that this review will inspire the microbiology community to embrace those tools in future studies so that host cell biomechanics can be more readily explored in the context of infection studies.
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Clarkson KA, Porter CK, Talaat KR, Kapulu MC, Chen WH, Frenck RW, Bourgeois AL, Kaminski RW, Martin LB. Shigella-Controlled Human Infection Models: Current and Future Perspectives. Curr Top Microbiol Immunol 2022. [PMID: 35616717 PMCID: PMC7616482 DOI: 10.1007/82_2021_248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Shigella-controlled human infection models (CHIMs) are an invaluable tool utilized by the vaccine community to combat one of the leading global causes of infectious diarrhea, which affects infants, children and adults regardless of socioeconomic status. The impact of shigellosis disproportionately affects children in low- and middle-income countries (LMICs) resulting in cognitive and physical stunting, perpetuating a cycle that must be halted. Shigella-CHIMs not only facilitate the early evaluation of enteric countermeasures and up-selection of the most promising products but also provide insight into mechanisms of infection and immunity that are not possible utilizing animal models or in vitro systems. The greater understanding of shigellosis obtained in CHIMs builds and empowers the development of new generation solutions to global health issues which are unattainable in the conventional laboratory and clinical settings. Therefore, refining, mining and expansion of safe and reproducible infection models hold the potential to create effective means to end diarrheal disease and associated co-morbidities associated with Shigella infection.
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Affiliation(s)
- Kristen A Clarkson
- Department of Diarrheal Disease Research, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA
| | - Chad K Porter
- Enteric Disease Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA
| | - Kawsar R Talaat
- Center for Immunization Research, Johns Hopkins Bloomberg School of Public Health, 624 North Broadway Street Hampton House, Baltimore, MD, 21205, USA
| | - Melissa C Kapulu
- Department of Biosciences, KEMRI-Wellcome Trust Research Programme, Kilifi County Hospital, Off Bofa Road, Kilifi, 80108, Kenya
| | - Wilbur H Chen
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, 685 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Robert W Frenck
- Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA
| | - A Louis Bourgeois
- PATH Center for Vaccine Innovation and Access, 455 Massachusetts Avenue NW, Washington, DC, 20001, USA
| | - Robert W Kaminski
- Department of Diarrheal Disease Research, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA
| | - Laura B Martin
- GSK Vaccines Institute for Global Health, Via Fiorentina 1, 53100, Siena, Italy.
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Cohen D, Meron-Sudai S, Bialik A, Asato V, Ashkenazi S. Detoxified O-Specific Polysaccharide (O-SP)-Protein Conjugates: Emerging Approach in the Shigella Vaccine Development Scene. Vaccines (Basel) 2022; 10:675. [PMID: 35632431 PMCID: PMC9145086 DOI: 10.3390/vaccines10050675] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/08/2022] [Accepted: 04/17/2022] [Indexed: 11/17/2022] Open
Abstract
Shigella is the second most common cause of moderate to severe diarrhea among children worldwide and of diarrheal disease-associated mortality in young children in low-and middle-income countries. In spite of many years of attempts to develop Shigella vaccines, no licensed vaccines are yet available. Injectable conjugate vaccines made of the detoxified lipopolysaccharide (LPS) of S. flexneri 2a, S. sonnei, and S. dysenteriae type 1 covalently bound to protein carriers were developed in the early 1990s by John B. Robbins and Rachel Schneerson at the US National Institutes of Health. This approach was novel for a disease of the gut mucosa, at a time when live, rationally attenuated oral vaccine strains that intended to mimic Shigella infection and induce a protective local immune response were extensively investigated. Of keystone support to Shigella glycoconjugates development were the findings of a strong association between pre-existent serum IgG antibodies to S. sonnei or S. flexneri 2a LPS and a lower risk of infection with the homologous Shigella serotypes among Israeli soldiers serving in field units. In view of these findings and of the successful development of the pioneering Haemophilus influenzae type b conjugate vaccines, it was hypothesized that protective immunity may be conferred by serum IgG antibodies to the O-Specific Polysaccharide (O-SP) following parenteral delivery of the conjugates. S. sonnei and S. flexneri 2a glycoconjugates induced high levels of serum IgG against the homologous LPS in phase I and II studies in healthy volunteers. The protective efficacy of a S. sonnei detoxified LPS-conjugate was further demonstrated in field trials in young adults (74%) and in children older than three years of age (71%), but not in younger ones. The evaluation of the Shigella conjugates confirmed that IgG antibodies to Shigella LPS are correlates of protection and provided solid basis for the development of a new generation of glycoconjugates and other injectable LPS-based vaccines that are currently in advanced stages of clinical evaluation.
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Affiliation(s)
- Dani Cohen
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; (S.M.-S.); (A.B.); (V.A.)
| | - Shiri Meron-Sudai
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; (S.M.-S.); (A.B.); (V.A.)
| | - Anya Bialik
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; (S.M.-S.); (A.B.); (V.A.)
| | - Valeria Asato
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel; (S.M.-S.); (A.B.); (V.A.)
| | - Shai Ashkenazi
- Adelson School of Medicine, Ariel University, Ariel 40700, Israel;
- Schneider Children’s Medical Center, Petach Tikva 49202, Israel
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9
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Ndungo E, Andronescu LR, Buchwald AG, Lemme-Dumit JM, Mawindo P, Kapoor N, Fairman J, Laufer MK, Pasetti MF. Repertoire of Naturally Acquired Maternal Antibodies Transferred to Infants for Protection Against Shigellosis. Front Immunol 2021; 12:725129. [PMID: 34721387 PMCID: PMC8554191 DOI: 10.3389/fimmu.2021.725129] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/27/2021] [Indexed: 11/13/2022] Open
Abstract
Shigella is the second leading cause of diarrheal diseases, accounting for >200,000 infections and >50,000 deaths in children under 5 years of age annually worldwide. The incidence of Shigella-induced diarrhea is relatively low during the first year of life and increases substantially, reaching its peak between 11 to 24 months of age. This epidemiological trend hints at an early protective immunity of maternal origin and an increase in disease incidence when maternally acquired immunity wanes. The magnitude, type, antigenic diversity, and antimicrobial activity of maternal antibodies transferred via placenta that can prevent shigellosis during early infancy are not known. To address this knowledge gap, Shigella-specific antibodies directed against the lipopolysaccharide (LPS) and virulence factors (IpaB, IpaC, IpaD, IpaH, and VirG), and antibody-mediated serum bactericidal (SBA) and opsonophagocytic killing antibody (OPKA) activity were measured in maternal and cord blood sera from a longitudinal cohort of mother-infant pairs living in rural Malawi. Protein-specific (very high levels) and Shigella LPS IgG were detected in maternal and cord blood sera; efficiency of placental transfer was 100% and 60%, respectively, and had preferential IgG subclass distribution (protein-specific IgG1 > LPS-specific IgG2). In contrast, SBA and OPKA activity in cord blood was substantially lower as compared to maternal serum and varied among Shigella serotypes. LPS was identified as the primary target of SBA and OPKA activity. Maternal sera had remarkably elevated Shigella flexneri 2a LPS IgM, indicative of recent exposure. Our study revealed a broad repertoire of maternally acquired antibodies in infants living in a Shigella-endemic region and highlights the abundance of protein-specific antibodies and their likely contribution to disease prevention during the first months of life. These results contribute new knowledge on maternal infant immunity and target antigens that can inform the development of vaccines or therapeutics that can extend protection after maternally transferred immunity wanes.
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Affiliation(s)
- Esther Ndungo
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Liana R. Andronescu
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Andrea G. Buchwald
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jose M. Lemme-Dumit
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Patricia Mawindo
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | | | | | - Miriam K. Laufer
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Marcela F. Pasetti
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States
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10
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Sarker P, Mily A, Ara A, Haque F, Maier N, Wierzba TF, Walker RI, Venkatesan MM, Raqib R. Functional antibodies and innate immune responses to WRSS1, a live oral Shigella sonnei vaccine candidate in Bangladeshi adults and children. J Infect Dis 2021; 224:S829-S839. [PMID: 34374425 PMCID: PMC8687094 DOI: 10.1093/infdis/jiab395] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background We demonstrated in a randomized placebo-controlled trial that WRSS1, a live oral Shigella sonnei vaccine candidate, is safe in Bangladeshi adults and children, and elicits antigen-specific antibodies. Here, we describe functional antibody and innate immune responses to WRSS1. Methods Adults (18–39 years) and children (5–9 years) received 3 doses of 3 × 105 or 3 × 106 colony forming units (CFU) of WRSS1 or placebo, 4 weeks apart; children additionally received 3 × 104 CFU. Blood and stool were collected at baseline and 7 days after each dose. Functional antibodies were measured using serum bactericidal antibody (SBA) assay. Cytokine/chemokine concentrations were measured in lymphocyte cultures. Host defense peptides LL-37, HBD-1, and HD-5 were analyzed in plasma and stool. Results Children showed increased SBA titers over baseline after the third dose of 3 × 106 CFU (P = .048). Significant increases of Th-17 and proinflammatory cytokines (TNF-α, G-CSF, MIP-1β), and reduction of anti-inflammatory and Th2 cytokines (IL-10, IL-13, GM-CSF) were observed in children. Plasma HBD-1 and LL-37 decreased in children after vaccination but were increased/unchanged in adults. Conclusions Functional antibodies and Th1/Th17 cytokine responses in children may serve as important indicators of immunogenicity and protective potential of WRSS1. Clinical Trials Registration: NCT01813071.
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Affiliation(s)
- Protim Sarker
- Infectious Diseases Division, icddr,b, Dhaka, Bangladesh
| | | | - Anjuman Ara
- Infectious Diseases Division, icddr,b, Dhaka, Bangladesh
| | - Farjana Haque
- Infectious Diseases Division, icddr,b, Dhaka, Bangladesh
| | - Nicole Maier
- Center for Vaccine Innovation and Access, PATH, Washington DC, USA
| | - Thomas F Wierzba
- Center for Vaccine Innovation and Access, PATH, Washington DC, USA
| | - Richard I Walker
- Center for Vaccine Innovation and Access, PATH, Washington DC, USA
| | - Malabi M Venkatesan
- Bacterial Diseases Branch, Walter Reed Army Institute of Research (WRAIR), Maryland, USA
| | - Rubhana Raqib
- Infectious Diseases Division, icddr,b, Dhaka, Bangladesh
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11
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Micoli F, Rossi O, Conti V, Launay O, Sciré AS, Aruta MG, Nakakana UN, Marchetti E, Rappuoli R, Saul A, Martin LB, Necchi F, Podda A. Antibodies Elicited by the Shigella sonnei GMMA Vaccine in Adults Trigger Complement-Mediated Serum Bactericidal Activity: Results From a Phase 1 Dose Escalation Trial Followed by a Booster Extension. Front Immunol 2021; 12:671325. [PMID: 34017343 PMCID: PMC8129577 DOI: 10.3389/fimmu.2021.671325] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 04/20/2021] [Indexed: 01/05/2023] Open
Abstract
Shigella is the second most deadly diarrheal disease among children under five years of age, after rotavirus, with high morbidity and mortality in developing countries. Currently, no vaccine is widely available, and the increasing levels of multidrug resistance make Shigella a high priority for vaccine development. The single-component candidate vaccine against Shigella sonnei (1790GAHB), developed using the GMMA technology, contains the O antigen (OAg) portion of lipopolysaccharide (LPS) as active moiety. The vaccine was well tolerated and immunogenic in early-phase clinical trials. In a phase 1 placebo-controlled dose escalation trial in France (NCT02017899), three doses of five different vaccine formulations (0.06/1, 0.3/5, 1.5/25, 3/50, 6/100 µg of OAg/protein) were administered to healthy adults. In the phase 1 extension trial (NCT03089879), conducted 2–3 years following the parent study, primed individuals who had undetectable antibody levels before the primary series received a 1790GAHB booster dose (1.5/25 µg OAg/protein). Controls were unprimed participants immunized with one 1790GAHB dose. The current analysis assessed the functionality of sera collected from both studies using a high-throughput luminescence-based serum bactericidal activity (SBA) assay optimized for testing human sera. Antibodies with complement-mediated bactericidal activity were detected in vaccinees but not in placebo recipients. SBA titers increased with OAg dose, with a persistent response up to six months after the primary vaccination with at least 1.5/25 µg of OAg/protein. The booster dose induced a strong increase of SBA titers in most primed participants. Correlation between SBA titers and anti-S. sonnei LPS serum immunoglobulin G levels was observed. Results suggest that GMMA is a promising OAg delivery system for the generation of functional antibody responses and persistent immunological memory.
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Affiliation(s)
| | - Omar Rossi
- GSK Vaccines Institute for Global Health, Siena, Italy
| | | | - Odile Launay
- Faculté de Médecine Paris Descartes, Université de Paris, Paris, France.,Inserm CIC 1417, F-CRIN I-REIVAC, Paris, France
| | | | | | | | | | - Rino Rappuoli
- GSK Vaccines Institute for Global Health, Siena, Italy
| | - Allan Saul
- GSK Vaccines Institute for Global Health, Siena, Italy
| | | | | | - Audino Podda
- GSK Vaccines Institute for Global Health, Siena, Italy
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12
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Samassa F, Ferrari ML, Husson J, Mikhailova A, Porat Z, Sidaner F, Brunner K, Teo TH, Frigimelica E, Tinevez JY, Sansonetti PJ, Thoulouze MI, Phalipon A. Shigella impairs human T lymphocyte responsiveness by hijacking actin cytoskeleton dynamics and T cell receptor vesicular trafficking. Cell Microbiol 2020; 22:e13166. [PMID: 31957253 PMCID: PMC7187243 DOI: 10.1111/cmi.13166] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/18/2019] [Accepted: 12/18/2019] [Indexed: 12/12/2022]
Abstract
Strategies employed by pathogenic enteric bacteria, such as Shigella, to subvert the host adaptive immunity are not well defined. Impairment of T lymphocyte chemotaxis by blockage of polarised edge formation has been reported upon Shigella infection. However, the functional impact of Shigella on T lymphocytes remains to be determined. Here, we show that Shigella modulates CD4+ T cell F‐actin dynamics and increases cell cortical stiffness. The scanning ability of T lymphocytes when encountering antigen‐presenting cells (APC) is subsequently impaired resulting in decreased cell–cell contacts (or conjugates) between the two cell types, as compared with non‐infected T cells. In addition, the few conjugates established between the invaded T cells and APCs display no polarised delivery and accumulation of the T cell receptor to the contact zone characterising canonical immunological synapses. This is most likely due to the targeting of intracellular vesicular trafficking by the bacterial type III secretion system (T3SS) effectors IpaJ and VirA. The collective impact of these cellular reshapings by Shigella eventually results in T cell activation dampening. Altogether, these results highlight the combined action of T3SS effectors leading to T cell defects upon Shigella infection.
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Affiliation(s)
- Fatoumata Samassa
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Mariana L Ferrari
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Julien Husson
- Laboratoire d'Hydrodynamique (LadHyX), Ecole polytechnique, CNRS, Institut Polytechnique de Paris, Palaiseau, France
| | | | - Ziv Porat
- Flow Cytometry Unit, Life Sciences Core Facility, Weizmann Institute of Sciences, Rehovot, Israel
| | | | - Katja Brunner
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Teck-Hui Teo
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | | | | | - Philippe J Sansonetti
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France.,Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | | | - Armelle Phalipon
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
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13
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Amadou Amani S, Lang ML. Bacteria That Cause Enteric Diseases Stimulate Distinct Humoral Immune Responses. Front Immunol 2020; 11:565648. [PMID: 33042146 PMCID: PMC7524877 DOI: 10.3389/fimmu.2020.565648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/18/2020] [Indexed: 12/12/2022] Open
Abstract
Bacterial enteric pathogens individually and collectively represent a serious global health burden. Humoral immune responses following natural or experimentally-induced infections are broadly appreciated to contribute to pathogen clearance and prevention of disease recurrence. Herein, we have compared observations on humoral immune mechanisms following infection with Citrobacter rodentium, the model for enteropathogenic Escherichia coli, Vibrio cholerae, Shigella species, Salmonella enterica species, and Clostridioides difficile. A comparison of what is known about the humoral immune responses to these pathogens reveals considerable variance in specific features of humoral immunity including establishment of high affinity, IgG class-switched memory B cell and long-lived plasma cell compartments. This article suggests that such variance could be contributory to persistent and recurrent disease.
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14
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Ndungo E, Pasetti MF. Functional antibodies as immunological endpoints to evaluate protective immunity against Shigella. Hum Vaccin Immunother 2019; 16:197-205. [PMID: 31287754 PMCID: PMC7670857 DOI: 10.1080/21645515.2019.1640427] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The development, clinical advancement and licensure of vaccines, and monitoring of vaccine effectiveness could be expedited and simplified by the ability to measure immunological endpoints that can predict a favorable clinical outcome. Antigen-specific and functional antibodies have been described in the context of naturally acquired immunity and vaccination against Shigella, and their presence in serum has been associated with reduced risk of disease in human subjects. The relevance of these antibodies as correlates of protective immunity, their mechanistic contribution to protection (e.g. target antigens, interference with pathogenesis, and participation in microbial clearance), and factors that influence their magnitude and makeup (e.g. host age, health condition, and environment) are important considerations that need to be explored. In addition to facilitating vaccine evaluation, immunological correlates of protection could be useful for identifying groups at risk and advancing immune therapies. Herein we discuss the precedent and value of functional antibodies as immunological endpoints to predict vaccine efficacy and the relevance of functional antibody activity to evaluate protective immunity against shigellosis.
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Affiliation(s)
- Esther Ndungo
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marcela F Pasetti
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
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15
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Su H, Liu Q, Wang S, Curtiss R, Kong Q. Regulated Delayed Shigella flexneri 2a O-antigen Synthesis in Live Recombinant Salmonella enterica Serovar Typhimurium Induces Comparable Levels of Protective Immune Responses with Constitutive Antigen Synthesis System. Am J Cancer Res 2019; 9:3565-3579. [PMID: 31281498 PMCID: PMC6587160 DOI: 10.7150/thno.33046] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/21/2019] [Indexed: 12/02/2022] Open
Abstract
Shigella flexneri (S. flexneri), a leading cause of bacillary dysentery, is a major public health concern particularly affecting children in developing nations. We have constructed a novel attenuated Salmonella vaccine system based on the regulated delayed antigen synthesis (RDAS) and regulated delayed expression of attenuating phenotype (RDEAP) systems for delivering the S. flexneri 2a (Sf2a) O-antigen. Methods: The new Salmonella vaccine platform was constructed through chromosomal integration of the araC PBAD lacI and araC PBAD wbaP cassettes, resulting in a gradual depletion of WbaP enzyme. An expression vector, encoding Sf2a O-antigen biosynthesis under the control of the LacI-repressible Ptrc promoter, was maintained in the Salmonella vaccine strain through antibiotic-independent selection. Mice immunized with the vaccine candidates were evaluated for cell-mediate and humoral immune responses. Results: In the presence of exogenous arabinose, the Salmonella vaccine strain synthesized native Salmonella LPS as a consequence of WbaP expression. Moreover, arabinose supported LacI expression, thereby repressing Sf2a O-antigen production. In the absence of arabinose in vivo, native Salmonella LPS synthesis is repressed whilst the synthesis of the Sf2a O-antigen is induced. Murine immunization with the Salmonella vaccine strain elicited robust Sf2a-specific protective immune responses together with long term immunity. Conclusion: These findings demonstrate the protective efficacy of recombinant Sf2a O-antigen delivered by a Salmonella vaccine platform.
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16
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Cohen D, Meron-Sudai S, Bialik A, Asato V, Goren S, Ariel-Cohen O, Reizis A, Hochberg A, Ashkenazi S. Serum IgG antibodies to Shigella lipopolysaccharide antigens - a correlate of protection against shigellosis. Hum Vaccin Immunother 2019; 15:1401-1408. [PMID: 31070988 DOI: 10.1080/21645515.2019.1606971] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Shigella is a leading cause of diarrhea among children globally and of diarrheal deaths among children under 5 years of age in low- and middle-income countries. To date, no licensed Shigella vaccine exists. We review evidence that serum IgG antibodies to Shigella LPS represent a good correlate of protection against shigellosis; this could support the process of development and evaluation of Shigella vaccine candidates. Case-control and cohort studies conducted among Israeli soldiers serving under field conditions showed significant serotype-specific inverse associations between pre-exposure serum IgG antibodies to Shigella LPS and shigellosis incidence. The same serum IgG fraction showed a dose-response relationship with the protective efficacy attained by vaccine candidates tested in phase III trials of young adults and children aged 1-4 years and in Controlled Human Infection Model studies and exhibited mechanistic protective capabilities. Identifying a threshold level of these antibodies associated with protection can promote the development of an efficacious vaccine for infants and young children.
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Affiliation(s)
- Dani Cohen
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Shiri Meron-Sudai
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Anya Bialik
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Valeria Asato
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Sophy Goren
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Ortal Ariel-Cohen
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Arava Reizis
- a School of Public Health, Sackler Faculty of Medicine , Tel Aviv University , Tel Aviv Israel
| | - Amit Hochberg
- b Newborn and Neonatal Care Department , Hillel Yaffe Medical Center , Hadera , Israel
| | - Shai Ashkenazi
- c Adelson School of Medicine , Ariel University, and Schneider Children's Medical Center , Israel
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17
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Brunner K, Samassa F, Sansonetti PJ, Phalipon A. Shigella-mediated immunosuppression in the human gut: subversion extends from innate to adaptive immune responses. Hum Vaccin Immunother 2019; 15:1317-1325. [PMID: 30964713 PMCID: PMC6663138 DOI: 10.1080/21645515.2019.1594132] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 02/13/2019] [Accepted: 02/27/2019] [Indexed: 02/07/2023] Open
Abstract
The enteropathogen, Shigella, is highly virulent and remarkably adjusted to the intestinal environment of its almost exclusive human host. Key for Shigella pathogenicity is the injection of virulence effectors into the host cell via its type three secretion system (T3SS), initiating disease onset and progression by the vast diversity of the secreted T3SS effectors and their respective cellular targets. The multifaceted modulation of host signaling pathways exerted by Shigella T3SS effectors, which include the subversion of host innate immune defenses and the promotion of intracellular bacterial survival and dissemination, have been extensively reviewed in the recent past. This review focuses on the human species specificity of Shigella by discussing some possible evasion mechanisms towards the human, but not non-human or rodent gut innate defense barrier, leading to the lack of a relevant animal infection model. In addition, subversion mechanisms of the adaptive immune response are highlighted summarizing research advances of the recent years. In particular, the new paradigm of Shigella pathogenicity constituted of invasion-independent T3SS effector-mediated targeting of activated, human lymphocytes is discussed. Along with consequences on vaccine development, these findings offer new directions for future research endeavors towards a better understanding of immunity to Shigella infection.
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Affiliation(s)
- Katja Brunner
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
| | - Fatoumata Samassa
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
| | - Philippe J. Sansonetti
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
- Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | - Armelle Phalipon
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
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18
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Raqib R, Sarker P, Zaman K, Alam NH, Wierzba TF, Maier N, Talukder K, Baqui AH, Suvarnapunya AE, Qadri F, Walker RI, Fix A, Venkatesan MM. A phase I trial of WRSS1, a Shigella sonnei live oral vaccine in Bangladeshi adults and children. Hum Vaccin Immunother 2019; 15:1326-1337. [PMID: 30794051 DOI: 10.1080/21645515.2019.1575165] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Shigella sonnei live vaccine candidate, WRSS1, which was previously evaluated in US, Israeli and Thai volunteers, was administered orally to Bangladeshi adults and children to assess its safety, clinical tolerability and immunogenicity. In a randomized, placebo-controlled, dose-escalation, age-descending study, 39 adults (18-39 years) and 64 children (5-9 years) were enrolled. Each adult cohort (n = 13) received one dose of 3x104, or three doses of 3 × 105 or 3 × 106 colony forming unit (CFU) of WRSS1 (n = 10) or placebo (n = 3). Each child cohort (n = 16) received one dose of 3x103, or three doses of 3x104, 3x105, or 3 × 106 CFU WRSS1 (n = 12) or placebo (n = 4). WRSS1 elicited mostly mild and transient reactogenicity events in adults and children. In the 3 × 106 dose group, 50% of the adults shed the vaccine; no shedding was seen in children. At the highest dose, 100% of adults and 40% of children responded with a ≥ 4-fold increase of S. sonnei LPS-specific IgA antibody in lymphocyte supernatant (ALS). At the same dose, 63% of adults and 70% of children seroconverted with IgA to LPS, while in placebo, 33% of adults and 18% of children seroconverted. Both the vaccinees and placebos responded with fecal IgA to LPS, indicating persistent exposure to Shigella infections. In conclusion, WRSS1 was found safe up to 106 CFU dose and immunogenic in adults and children in Bangladesh. These data indicate that live, oral Shigella vaccine candidates, including WRSS1 can potentially be evaluated in toddlers and infants (<2 years of age), who comprise the target population in an endemic environment.
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Affiliation(s)
- Rubhana Raqib
- a Infectious Diseases Division , icddr,b , Dhaka , Bangladesh
| | - Protim Sarker
- a Infectious Diseases Division , icddr,b , Dhaka , Bangladesh
| | - K Zaman
- a Infectious Diseases Division , icddr,b , Dhaka , Bangladesh
| | - Nur Haque Alam
- b Nutrition and Clinical Services Division , icddr,b , Dhaka , Bangladesh
| | - Thomas F Wierzba
- c Center for Vaccine Innovation and Access , PATH , Washington , DC , USA
| | - Nicole Maier
- c Center for Vaccine Innovation and Access , PATH , Washington , DC , USA
| | - Kaisar Talukder
- d Laboratory Sciences and Services Division , icddr,b , Dhaka , Bangladesh
| | - Abdullah Hel Baqui
- e Johns Hopkins Bloomberg School of Public Health , Johns Hopkins University , Baltimore , MD , USA
| | - Akamol E Suvarnapunya
- f Bacterial Diseases Branch , Walter Reed Army Institute of Research , Silver Spring , MD , USA
| | - Firdausi Qadri
- a Infectious Diseases Division , icddr,b , Dhaka , Bangladesh
| | - Richard I Walker
- c Center for Vaccine Innovation and Access , PATH , Washington , DC , USA
| | - Alan Fix
- c Center for Vaccine Innovation and Access , PATH , Washington , DC , USA
| | - Malabi M Venkatesan
- f Bacterial Diseases Branch , Walter Reed Army Institute of Research , Silver Spring , MD , USA
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19
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Ledov VA, Golovina ME, Markina AA, Knirel YA, L'vov VL, Kovalchuk AL, Aparin PG. Highly homogenous tri-acylated S-LPS acts as a novel clinically applicable vaccine against Shigella flexneri 2a infection. Vaccine 2019; 37:1062-1072. [PMID: 30670300 DOI: 10.1016/j.vaccine.2018.12.067] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 12/08/2018] [Accepted: 12/30/2018] [Indexed: 12/24/2022]
Abstract
Shigellosis, a major cause of diarrhea worldwide, exhibits high morbidity and mortality in children. Specificity of Shigella immunity is determined by the structure of the main protective O-antigen polysaccharide component incorporated into the lipopolysaccharide (LPS) molecule. Endotoxicity, however, precludes LPS clinical use. Thus, there is still no vaccine against the most prevalent shigellosis species (serotype S. flexneri 2a), despite ongoing efforts focused on inducing serotype-specific immunity. As LPS is highly heterogenous, we hypothesized that more homogenous pools of LPS might be less toxic. We developed a method to generate a homogenous S. flexneri 2a LPS subfraction, Ac3-S-LPS, containing long chain O-specific polysaccharide (S-LPS) and mainly tri-acylated lipid A, with no penta- and hexa-acylated, and rare tetra-acylated lipid A. Ac3-S-LPS had dramatically reduced pyrogenicity and protected guinea pigs from shigellosis. In volunteers, 50 µg of injected Ac3-S-LPS vaccine was safe, with low pyrogenicity, no severe and few minor adverse events, and did not induce pro-inflammatory cytokines. In spite of the profound lipid A modification, the vaccine induced a prevalence of IgG and IgA antibodies. Thus, we have developed the first safe immunogenic LPS-based vaccine candidate for human administration. Homogenous underacetylated LPSs may also be useful for treating other LPS-driven human diseases. Clinical trial registry: http://grls.rosminzdrav.ru/.
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Affiliation(s)
- Vladimir A Ledov
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Marina E Golovina
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Anna A Markina
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Yuriy A Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47, Leninsky Prospect, Moscow 117913, Russia
| | - Vyacheslav L L'vov
- Laboratory of Preparative Biochemistry, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Alexander L Kovalchuk
- The Virology and Cellular Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, United States
| | - Petr G Aparin
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia.
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20
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Ndungo E, Randall A, Hazen TH, Kania DA, Trappl-Kimmons K, Liang X, Barry EM, Kotloff KL, Chakraborty S, Mani S, Rasko DA, Pasetti MF. A Novel Shigella Proteome Microarray Discriminates Targets of Human Antibody Reactivity following Oral Vaccination and Experimental Challenge. mSphere 2018; 3:e00260-18. [PMID: 30068560 PMCID: PMC6070737 DOI: 10.1128/msphere.00260-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022] Open
Abstract
Shigella spp. are a major cause of diarrhea and dysentery in children under 5 years old in the developing world. The development of an effective vaccine remains a public health priority, necessitating improved understanding of immune responses to Shigella and identification of protective antigens. We report the development of a core Shigella proteome microarray consisting of 2,133 antigen targets common to all Shigella species. We evaluated the microarray with serum samples from volunteers immunized with either an inactivated whole-cell S. flexneri serotype 2a (Sf2aWC) vaccine or a live attenuated S. flexneri 2a vaccine strain (CVD 1204) or challenged with wild-type S. flexneri 2a (Sf2a challenge). Baseline reactivities to most antigens were detected postintervention in all three groups. Similar immune profiles were observed after CVD 1204 vaccination and Sf2a challenge. Antigens with the largest increases in mean reactivity postintervention were members of the type three secretion system (T3SS), some of which are regarded as promising vaccine targets: these are the invasion plasmid antigens (Ipas) IpaB, IpaC, and IpaD. In addition, new immunogenic targets (IpaA, IpaH, and SepA) were identified. Importantly, immunoreactivities to antigens in the microarray correlated well with antibody titers determined by enzyme-linked immunosorbent assay (ELISA), validating the use of the microarray platform. Finally, our analysis uncovered an immune signature consisting of three conserved proteins (IpaA, IpaB, and IpaC) that was predictive of protection against shigellosis. In conclusion, the Shigella proteome microarray is a robust platform for interrogating serological reactivity to multiple antigens at once and identifying novel targets for the development of broadly protective vaccines.IMPORTANCE Each year, more than 180 million cases of severe diarrhea caused by Shigella occur globally. Those affected (mostly children in poor regions) experience long-term sequelae that severely impair quality of life. Without a licensed vaccine, the burden of disease represents a daunting challenge. An improved understanding of immune responses to Shigella is necessary to support ongoing efforts to identify a safe and effective vaccine. We developed a microarray containing >2,000 proteins common to all Shigella species. Using sera from human adults who received a killed whole-cell or live attenuated vaccine or were experimentally challenged with virulent organisms, we identified new immune-reactive antigens and defined a T3SS protein signature associated with clinical protection.
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Affiliation(s)
- Esther Ndungo
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Arlo Randall
- Antigen Discovery, Inc., Irvine, California, USA
| | - Tracy H Hazen
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dane A Kania
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Xiaowu Liang
- Antigen Discovery, Inc., Irvine, California, USA
| | - Eileen M Barry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | - David A Rasko
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Marcela F Pasetti
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
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21
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Sultana S, Sarker SA, Brüssow H. What happened toKoch's postulates in diarrhoea? Environ Microbiol 2017; 19:2926-2934. [DOI: 10.1111/1462-2920.13787] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 04/28/2017] [Indexed: 01/18/2023]
Affiliation(s)
- Shamima Sultana
- Clinical Sciences DepartmentInternational Center for Diarrhoeal Disease ResearchDhaka Bangladesh
| | - Shafiqul A. Sarker
- Clinical Sciences DepartmentInternational Center for Diarrhoeal Disease ResearchDhaka Bangladesh
| | - Harald Brüssow
- Department of Gut Ecology, Host‐Microbe Interaction GroupNestlé Research CenterLausanne Switzerland
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22
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Functional and Antigen-Specific Serum Antibody Levels as Correlates of Protection against Shigellosis in a Controlled Human Challenge Study. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00412-16. [PMID: 27927680 PMCID: PMC5299116 DOI: 10.1128/cvi.00412-16] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/29/2016] [Indexed: 11/29/2022]
Abstract
Shigella is an important cause of diarrheal disease in young children living in developing countries. No approved vaccines are available, and the development of vaccine candidates has been hindered by the lack of firm immunological correlates of protection, among other reasons. To address this gap in knowledge, we established quantitative assays to measure Shigella-specific serum bactericidal antibody (SBA) and opsonophagocytic killing antibody (OPKA) activities and investigated their potential association with protection against disease in humans. SBA, OPKA, and Ipa-, VirG (IscA)-, and Shigella flexneri 2a lipopolysaccharide-specific serum IgG titers were determined in adult volunteers who received Shigella vaccine candidate EcSf2a-2 and in unvaccinated controls, all of whom were challenged with virulent Shigella flexneri 2a. Prechallenge antibody titers were compared with disease severity after challenge. SBA and OPKA, as well as IpaB- and VirG-specific IgG, significantly correlated with reduced illness. SBA and OPKA assays were also used to evaluate the immunogenicity of leading live attenuated vaccine candidates Shigella CVD 1204 and CVD 1208S in humans. A single oral immunization with CVD 1204 or CVD 1208S resulted in SBA seroconversion rates of 71% and 47% and OPKA seroconversion rates of 57% and 35%, respectively. Higher functional antibody responses were induced by CVD 1204, which is consistent with its lower attenuation. This is the first demonstration of SBA, OPKA, and IpaB- and VirG-specific IgG levels as potential serological correlates of protection against shigellosis in humans. These results warrant further studies to establish their capacity to predict protective immunity and vaccine efficacy.
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23
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The Orchestra and Its Maestro: Shigella's Fine-Tuning of the Inflammasome Platforms. Curr Top Microbiol Immunol 2016; 397:91-115. [PMID: 27460806 DOI: 10.1007/978-3-319-41171-2_5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Shigella spp. are the causative agents of bacillary dysentery, leading to extensive mortality and morbidity worldwide. These facultative intracellular bacteria invade the epithelium of the colon and the rectum, inducing a severe inflammatory response from which the symptoms of the disease originate. Shigella are human pathogens able to manipulate and subvert the innate immune system surveillance. Shigella dampens inflammasome activation in epithelial cells. In infected macrophages, inflammasome activation and IL-1β and IL-18 release lead to massive neutrophil recruitment and greatly contribute to inflammation. Here, we describe how Shigella hijacks and finely tunes inflammasome activation in the different cell populations involved in pathogenesis: epithelial cells, macrophages, neutrophils, DCs, and B and T lymphocytes. Shigella emerges as a "sly" pathogen that switches on/off the inflammasome mechanisms in order to optimize the interaction with the host and establish a successful infection.
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24
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Abstract
Many preclinical studies in critical care medicine and related disciplines rely on hypothesis-driven research in mice. The underlying premise posits that mice sufficiently emulate numerous pathophysiologic alterations produced by trauma/sepsis and can serve as an experimental platform for answering clinically relevant questions. Recently, the lay press severely criticized the translational relevance of mouse models in critical care medicine. A series of provocative editorials were elicited by a highly publicized research report in the Proceedings of the National Academy of Sciences (PNAS; February 2013), which identified an unrecognized gene expression profile mismatch between human and murine leukocytes following burn/trauma/endotoxemia. Based on their data, the authors concluded that mouse models of trauma/inflammation are unsuitable for studying corresponding human conditions. We believe this conclusion was not justified. In conjunction with resulting negative commentary in the popular press, it can seriously jeopardize future basic research in critical care medicine. We will address some limitations of that PNAS report to provide a framework for discussing its conclusions and attempt to present a balanced summary of strengths/weaknesses of use of mouse models. While many investigators agree that animal research is a central component for improved patient outcomes, it is important to acknowledge known limitations in clinical translation from mouse to man. The scientific community is responsible to discuss valid limitations without overinterpretation. Hopefully, a balanced view of the strengths/weaknesses of using animals for trauma/endotoxemia/critical care research will not result in hasty discount of the clear need for using animals to advance treatment of critically ill patients.
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25
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Nothelfer K, Arena ET, Pinaud L, Neunlist M, Mozeleski B, Belotserkovsky I, Parsot C, Dinadayala P, Burger-Kentischer A, Raqib R, Sansonetti PJ, Phalipon A. B lymphocytes undergo TLR2-dependent apoptosis upon Shigella infection. ACTA ACUST UNITED AC 2014; 211:1215-29. [PMID: 24863068 PMCID: PMC4042640 DOI: 10.1084/jem.20130914] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Shigella flexneri interacts with B cells and induces apoptosis via IpaD binding to TLR2. Antibody-mediated immunity to Shigella, the causative agent of bacillary dysentery, requires several episodes of infection to get primed and is short-lasting, suggesting that the B cell response is functionally impaired. We show that upon ex vivo infection of human colonic tissue, invasive S. flexneri interacts with and occasionally invades B lymphocytes. The induction of a type three secretion apparatus (T3SA)–dependent B cell death is observed in the human CL-01 B cell line in vitro, as well as in mouse B lymphocytes in vivo. In addition to cell death occurring in Shigella-invaded CL-01 B lymphocytes, we provide evidence that the T3SA needle tip protein IpaD can induce cell death in noninvaded cells. IpaD binds to and induces B cell apoptosis via TLR2, a signaling receptor thus far considered to result in activation of B lymphocytes. The presence of bacterial co-signals is required to sensitize B cells to apoptosis and to up-regulate tlr2, thus enhancing IpaD binding. Apoptotic B lymphocytes in contact with Shigella-IpaD are detected in rectal biopsies of infected individuals. This study therefore adds direct B lymphocyte targeting to the diversity of mechanisms used by Shigella to dampen the host immune response.
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Affiliation(s)
- Katharina Nothelfer
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France
| | - Ellen T Arena
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France
| | - Laurie Pinaud
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur UPMC, 75013 Paris, France
| | - Michel Neunlist
- INSERM U913, Institut des Maladies de l'Appareil Digestif du Centre Hospitalier Universitaire de Nantes, 44093 Nantes, France
| | - Brian Mozeleski
- Institut Pasteur, INSERM U1041, Unité de Régulation Immunitaire et Vaccinologie, 75015 Paris, France Institut Pasteur, INSERM U1041, Unité de Régulation Immunitaire et Vaccinologie, 75015 Paris, France
| | - Ilia Belotserkovsky
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France
| | - Claude Parsot
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France
| | | | - Anke Burger-Kentischer
- Molekulare Biotechnologie, Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB, 70569 Stuttgart, Germany
| | - Rubhana Raqib
- Laboratory Sciences Division, International Centre for Diarrhoeal Diseases Research, Bangladesh (ICDDR,B), Dhaka 1000, Bangladesh
| | - Philippe J Sansonetti
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France Chaire de Microbiologie et Maladies Infectieuses, Collège de France, 75005 Paris, France
| | - Armelle Phalipon
- Institut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, FranceInstitut Pasteur, INSERM U786, Unité de Pathogénie Microbienne Moléculaire, 75015 Paris, France
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26
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Abstract
Renewed awareness of the substantial morbidity and mortality that Shigella infection causes among young children in developing countries, combined with technological innovations in vaccinology, has led to the development of novel vaccine strategies in the past 5 years. Along with advancement of classic vaccines in clinical trials and new sophisticated measurements of immunological responses, much new data has been produced, lending promise to the potential for production of safe and effective Shigella vaccines. Herein, we review the latest progress in Shigella vaccine development within the framework of persistent obstacles.
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27
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Abstract
The Gram-negative enteroinvasive bacterium Shigella flexneri is responsible for the endemic form of bacillary dysentery, an acute rectocolitis in humans. S. flexneri uses a type III secretion system to inject effector proteins into host cells, thus diverting cellular functions to its own benefit. Protective immunity to reinfection requires several rounds of infection to be elicited and is short-lasting, suggesting that S. flexneri interferes with the priming of specific immunity. Considering the key role played by T-lymphocyte trafficking in priming of adaptive immunity, we investigated the impact of S. flexneri on T-cell dynamics in vivo. By using two-photon microscopy to visualize bacterium-T-cell cross-talks in the lymph nodes, where the adaptive immunity is initiated, we provide evidence that S. flexneri, via its type III secretion system, impairs the migration pattern of CD4(+) T cells independently of cognate recognition of bacterial antigens. We show that bacterial invasion of CD4(+) T lymphocytes occurs in vivo, and results in cell migration arrest. In the absence of invasion, CD4(+) T-cell migration parameters are also dramatically altered. Signals resulting from S. flexneri interactions with subcapsular sinus macrophages and dendritic cells, and recruitment of polymorphonuclear cells are likely to contribute to this phenomenon. These findings indicate that S. flexneri targets T lymphocytes in vivo and highlight the role of type III effector secretion in modulating host adaptive immune responses.
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28
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Broadly protective Shigella vaccine based on type III secretion apparatus proteins. Infect Immun 2011; 80:1222-31. [PMID: 22202122 DOI: 10.1128/iai.06174-11] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Shigella spp. are food- and waterborne pathogens that cause severe diarrheal and dysenteric disease associated with high morbidity and mortality. Individuals most often affected are children under 5 years of age in the developing world. The existence of multiple Shigella serotypes and the heterogenic distribution of pathogenic strains, as well as emerging antibiotic resistance, require the development of a broadly protective vaccine. All Shigella spp. utilize a type III secretion system (TTSS) to initiate infection. The type III secretion apparatus (TTSA) is the molecular needle and syringe that form the energized conduit between the bacterial cytoplasm and the host cell to transport effector proteins that manipulate cellular processes to benefit the pathogen. IpaB and IpaD form a tip complex atop the TTSA needle and are required for pathogenesis. Because they are common to all virulent Shigella spp., they are ideal candidate antigens for a subunit-based, broad-spectrum vaccine. We examined the immunogenicity and protective efficacy of IpaB and IpaD, alone or combined, coadministered with a double mutant heat-labile toxin (dmLT) from Escherichia coli, used as a mucosal adjuvant, in a mouse model of intranasal immunization and pulmonary challenge. Robust systemic and mucosal antibody- and T cell-mediated immunities were induced against both proteins, particularly IpaB. Mice immunized in the presence of dmLT with IpaB alone or IpaB combined with IpaD were fully protected against lethal pulmonary infection with Shigella flexneri and Shigella sonnei. We provide the first demonstration that the Shigella TTSAs IpaB and IpaD are promising antigens for the development of a cross-protective Shigella vaccine.
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29
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Abstract
CD8(+) T lymphocytes often play a primary role in adaptive immunity to cytosolic microbial pathogens. Surprisingly, CD8(+) T cells are not required for protective immunity to the enteric pathogen Shigella flexneri, despite the ability of Shigella to actively secrete proteins into the host cytoplasm, a location from which antigenic peptides are processed for presentation to CD8(+) T cells. To determine why CD8(+) T cells fail to play a role in adaptive immunity to S. flexneri, we investigated whether antigen-specific CD8(+) T cells are primed during infection but are unable to confer protection or, alternatively, whether T cells fail to be primed. To test whether Shigella is capable of stimulating an antigen-specific CD8(+) T-cell response, we created an S. flexneri strain that constitutively secretes a viral CD8(+) T-cell epitope via the Shigella type III secretion system and characterized the CD8(+) T-cell response to this strain both in mice and in cultured cells. Surprisingly, no T cells specific for the viral epitope were stimulated in mice infected with this strain, and cells infected with the recombinant strain were not targeted by epitope-specific T cells. Additionally, we found that the usually robust T-cell response to antigens artificially introduced into the cytoplasm of cultured cells was significantly reduced when the antigen-presenting cell was infected with Shigella. Collectively, these results suggest that antigen-specific CD8(+) T cells are not primed during S. flexneri infection and, as a result, afford little protection to the host during primary or subsequent infection.
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30
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Rahman KM, Arifeen SE, Zaman K, Rahman M, Raqib R, Yunus M, Begum N, Islam MS, Sohel BM, Rahman M, Venkatesan M, Hale TL, Isenbarger DW, Sansonetti PJ, Black RE, Baqui AH. Safety, dose, immunogenicity, and transmissibility of an oral live attenuated Shigella flexneri 2a vaccine candidate (SC602) among healthy adults and school children in Matlab, Bangladesh. Vaccine 2010; 29:1347-54. [PMID: 21040694 DOI: 10.1016/j.vaccine.2010.10.035] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 09/10/2010] [Accepted: 10/13/2010] [Indexed: 11/30/2022]
Abstract
In double-blind trials in Bangladesh, 88 adults, and 79 children (8-10 years) were randomized to receive either a single oral dose of 1 × 10(4), 1 × 10(5) or 1 × 10(6)CFU of SC602 (a live, attenuated Shigella flexneri 2a strain vaccine) or placebo. In the adult outpatient 1 × 10(6) CFU group, severe joint pain and body aches were reported by one and two vaccinees respectively. In the adult inpatient trial, SC602 was isolated from 3 volunteers, pre-vaccination antibody titers were high, and fourfold increases in serum IgG anti-LPS responses were observed in 2 of 5 subjects of the 1 × 10(6)CFU group. None of the volunteers developed diarrhea. Overall, SC602 was found to be associated with minimal vaccine shedding, minimal reactogenicity, no transmission risk, and low immune stimulation.
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31
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Kaminski RW, Oaks EV. Inactivated and subunit vaccines to prevent shigellosis. Expert Rev Vaccines 2010; 8:1693-704. [PMID: 19943764 DOI: 10.1586/erv.09.127] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Shigellosis remains a formidable disease globally, with children of the developing world bearing the greatest number of infections. The need for an affordable, safe and efficacious vaccine has persisted for decades. Vaccines to prevent shigellosis can be divided into living and nonliving approaches. Several nonliving Shigella vaccines are currently at different stages of development and show substantial promise. Outlined here is an overview of multiple nonliving vaccine technologies, highlighting their current status and recent advances in testing. In addition, gaps in the knowledge base regarding immune mechanisms of protection are explored.
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Affiliation(s)
- Robert W Kaminski
- Division of Bacterial and Rickettsial Diseases, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
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32
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Levine MM, Kotloff KL, Barry EM, Pasetti MF, Sztein MB. Clinical trials of Shigella vaccines: two steps forward and one step back on a long, hard road. Nat Rev Microbiol 2007; 5:540-53. [PMID: 17558427 PMCID: PMC3771495 DOI: 10.1038/nrmicro1662] [Citation(s) in RCA: 266] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
More than 50 years of research has yielded numerous Shigella vaccine candidates that have exemplified both the promise of vaccine-induced prevention of shigellosis and the impediments to developing a safe and effective vaccine for widespread use, a goal that has yet to be attained. This Review discusses the most advanced strategies for Shigella vaccine development, the immune responses that are elicited following disease or vaccination, the factors that have accelerated or impeded Shigella vaccine development and our ideas for the way forward.
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MESH Headings
- Antibodies, Bacterial/blood
- Child, Preschool
- Clinical Trials as Topic
- Dysentery, Bacillary/epidemiology
- Dysentery, Bacillary/immunology
- Dysentery, Bacillary/microbiology
- Dysentery, Bacillary/prevention & control
- Humans
- Immunity, Cellular
- Infant
- Shigella/classification
- Shigella/immunology
- Shigella Vaccines/administration & dosage
- Shigella Vaccines/adverse effects
- Shigella Vaccines/immunology
- Vaccination
- Vaccines, Attenuated/administration & dosage
- Vaccines, Attenuated/adverse effects
- Vaccines, Attenuated/immunology
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Affiliation(s)
- Myron M Levine
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
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33
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Phalipon A, Sansonetti PJ. Shigella’
s ways of manipulating the host intestinal innate and adaptive immune system: a tool box for survival? Immunol Cell Biol 2007; 85:119-29. [PMID: 17213832 DOI: 10.1038/sj.icb7100025] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Shigella, a Gram-negative invasive enteropathogenic bacterium, causes the rupture, invasion and inflammatory destruction of the human colonic epithelium. This complex and aggressive process accounts for the symptoms of bacillary dysentery. The so-called invasive phenotype of Shigella is linked to expression of a type III secretory system (TTSS) injecting effector proteins into the epithelial cell membrane and cytoplasm, thereby inducing local but massive changes in the cell cytoskeleton that lead to bacterial internalization into non-phagocytic intestinal epithelial cells. The invasive phenotype also accounts for the potent pro-inflammatory capacity of the microorganism. Recent evidence indicates that a large part of the mucosal inflammation is initiated by intracellular sensing of bacterial peptidoglycan by cytosolic leucine-rich receptors of the NOD family, particularly NOD1, in epithelial cells. This causes activation of the nuclear factor kappa B and c-JunNH(2)-terminal-kinase pathways, with interleukin-8 appearing as a major chemokine mediating the inflammatory burst that is dominated by massive infiltration of the mucosa by polymorphonuclear leukocytes. Not unexpectedly, this inflammatory response, which is likely to be very harmful for the invading microbe, is regulated by the bacterium itself. A group of proteins encoded by Shigella, which are injected into target cells by the TTSS, has been recently recognized as a family of potent regulators of the innate immune response. These enzymes target key cellular functions that are essential in triggering the inflammatory response, and more generally defense responses of the intestinal mucosa. This review focuses on the mechanisms employed by Shigella to manipulate the host innate response in order to escape early bacterial killing, thus ensuring establishment of its infectious process. The escape strategies, the possible direct effect of Shigella on B and T lymphocytes, their impact on the development of adaptive immunity, and how they may help explain the limited protection induced by natural infection are discussed.
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Affiliation(s)
- Armelle Phalipon
- Unité de Pathogénie Microbienne Moléculaire, INSERM U786, Institut Pasteur 25, Rue du Dr Roux, Paris, France.
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34
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Jennison AV, Roberts F, Verma NK. Construction of a multivalent vaccine strain ofShigella flexneriand evaluation of serotype-specific immunity. ACTA ACUST UNITED AC 2006; 46:444-51. [PMID: 16553820 DOI: 10.1111/j.1574-695x.2006.00062.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Shigella flexneri causes more fatalities by shigellosis than any other Shigella species. There are 13 different serotypes of S. flexneri and their distribution varies between endemic geographical regions. The immune response against S. flexneri is serotype-specific, so current immunization strategies have required the administration of multiple vaccine strains to provide protection against multiple serotypes. In this study, we report the construction of a multivalent S. flexneri vaccine strain, SFL1425, expressing the O-antigen structure specific for serotypes 2a and 5a. This combination of type antigens has not previously been reported for S. flexneri. The multivalent vaccine strain, SFL1425 was able to induce a specific immune response against both serotypes 2a and 5a in a mouse pulmonary model.
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MESH Headings
- Animals
- Antibodies, Bacterial/blood
- Blotting, Southern
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Dysentery, Bacillary/immunology
- Dysentery, Bacillary/microbiology
- Dysentery, Bacillary/prevention & control
- Enzyme-Linked Immunosorbent Assay
- Female
- Mice
- Mice, Inbred BALB C
- O Antigens/genetics
- O Antigens/immunology
- Polymerase Chain Reaction
- Shigella Vaccines/genetics
- Shigella Vaccines/immunology
- Shigella Vaccines/pharmacology
- Shigella flexneri/genetics
- Shigella flexneri/immunology
- Species Specificity
- Vaccines, Attenuated/genetics
- Vaccines, Attenuated/immunology
- Vaccines, Attenuated/pharmacology
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Affiliation(s)
- Amy V Jennison
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, Australia
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35
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Jennison AV, Verma NK. Shigella flexneri infection: pathogenesis and vaccine development. FEMS Microbiol Rev 2004; 28:43-58. [PMID: 14975529 DOI: 10.1016/j.femsre.2003.07.002] [Citation(s) in RCA: 172] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2003] [Revised: 07/25/2003] [Accepted: 07/30/2003] [Indexed: 02/08/2023] Open
Abstract
Shigella flexneri is a gram-negative bacterium which causes the most communicable of bacterial dysenteries, shigellosis. Shigellosis causes 1.1 million deaths and over 164 million cases each year, with the majority of cases occurring in the children of developing nations. The pathogenesis of S. flexneri is based on the bacteria's ability to invade and replicate within the colonic epithelium, which results in severe inflammation and epithelial destruction. The molecular mechanisms used by S. flexneri to cross the epithelial barrier, evade the host's immune response and enter epithelial cells have been studied extensively in both in vitro and in vivo models. Consequently, numerous virulence factors essential to bacterial invasion, intercellular spread and the induction of inflammation have been identified in S. flexneri. The inflammation produced by the host has been implicated in both the destruction of the colonic epithelium and in controlling and containing the Shigella infection. The host's humoral response to S. flexneri also appears to be important in protecting the host, whilst the role of the cellular immune response remains unclear. The host's immune response to shigellosis is serotype-specific and protective against reinfection by the same serotype, making vaccination a possibility. Since the 1940s vaccines for S. flexneri have been developed with little success, however, the growing understanding of S. flexneri's pathogenesis and the host's immune response is assisting in the generation of more refined vaccine strategies. Current research encompasses a variety of vaccine types, which despite disparity in their efficacy and safety in humans represent promising progress in S. flexneri vaccine development.
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Affiliation(s)
- Amy V Jennison
- Faculty of Science, School of Biochemistry and Molecular Biology, The Australian National University, Canberra, ACT 0200, Australia
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Raqib R, Roy SK, Rahman MJ, Azim T, Ameer SS, Chisti J, Andersson J. Effect of zinc supplementation on immune and inflammatory responses in pediatric patients with shigellosis. Am J Clin Nutr 2004; 79:444-50. [PMID: 14985220 DOI: 10.1093/ajcn/79.3.444] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Several studies showed benefits of long-term zinc supplementation on the incidence, severity, and duration of diarrhea and on the incidence of respiratory infections. Prolonged zinc supplementation also improves cell-mediated immunity in severely malnourished children. OBJECTIVE We studied the effect of short-term zinc supplementation on intrinsic and specific immune and inflammatory responses in moderately malnourished children with acute shigellosis. DESIGN A randomized, double-blind, placebo-controlled trial was conducted in Shigella-infected children aged 12-59 mo. Elemental zinc (20 mg) and a multivitamin containing vitamins A and D, thiamine, riboflavin, nicotinamide, and calcium at twice the recommended dietary allowance were given daily for 2 wk to the zinc group (n = 28), whereas the multivitamin alone was given to the control group (n = 28). Standard antibiotic therapy was given to all patients. RESULTS Serum zinc concentrations increased in both groups during convalescence; however, zinc supplementation showed a significant effect. The lymphocyte proliferation response in the zinc group increased relative to that in the control group (P = 0.002), but no significant effects were seen on concentrations of cytokines (interleukin 2 and interferon gamma) released from mitogen-stimulated mononuclear cells or on concentrations of cytokines (interleukin 2, interferon gamma, and interleukin 1beta) in feces. Among the antigen [lipopolysaccharide and invasion plasmid-encoded antigen (Ipa)]-specific antibodies, plasma Ipa-specific immunoglobulin G responses at day 30 were significantly higher in the zinc group than in the control group. However, the 2 groups did not differ significantly in the other antigen-specific responses in plasma and stool. CONCLUSION A 14-d course of zinc supplementation during acute shigellosis increases the lymphocyte proliferation response and the Ipa-specific immunoglobulin G response.
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Affiliation(s)
- Rubhana Raqib
- International Centre for Diarrhoeal Diseases Research, Bangladesh (ICDDR,B): Centre for Health and Population Research, Dhaka, Bangladesh.
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Lan R, Stevenson G, Reeves PR. Comparison of two major forms of the Shigella virulence plasmid pINV: positive selection is a major force driving the divergence. Infect Immun 2003; 71:6298-306. [PMID: 14573649 PMCID: PMC219609 DOI: 10.1128/iai.71.11.6298-6306.2003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
All Shigella and enteroinvasive Escherichia coli (EIEC) strains carry a 230-kb virulence plasmid (pINV) which is essential for their invasiveness. There are two sequence forms, pINV A and pINV B, of the plasmid (R. Lan, B. Lumb, D. Ryan, and P. R. Reeves, Infect. Immun. 69:6303-6309, 2001), and the recently sequenced pINV plasmid from Shigella flexneri serotype 5 is a pINV B form. In this study we sequenced the majority of the coding region of the pINV A form from S. flexneri serotype 6 other than insertion sequence or related sequences and compared it with the pINV B form. More than half of the genes sequenced appear to be under positive selection based on their low ratio of synonymous to nonsynonymous substitutions. This high proportion of selected differences indicates that the two pINV forms have functional differences, and comparative studies of pathogenicity in different Shigella-EIEC strains could be informative. There are also genes absent in the S. flexneri serotype 6 plasmid, including the sepA gene encoding serine protease, the major secreted protein of S. flexneri serotype 2a, and the stbAB genes, which encode one of the two partition systems found in S. flexneri serotype 5. The incompatibility of the two pINV forms appears to be due to either small differences in the mvpAT postsegregational killing system or the presence of an unknown system in pINVA.
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Affiliation(s)
- Ruiting Lan
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney, Australia
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Raqib R, Moly PK, Sarker P, Qadri F, Alam NH, Mathan M, Andersson J. Persistence of mucosal mast cells and eosinophils in Shigella-infected children. Infect Immun 2003; 71:2684-92. [PMID: 12704143 PMCID: PMC153256 DOI: 10.1128/iai.71.5.2684-2692.2003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cells of the innate immune system and their mediators were studied at the single-cell level in the rectums of pediatric and adult patients with Shigella infection to better understand why children are at higher risk for severe infection. Adult patients had increased infiltration of mucosal mast cells (MMC) at the acute stage (3 to 5 days after the onset of diarrhea) and eosinophils in early convalescence (14 to 16 days after onset). Increased expression of stem cell factor and prostaglandin H synthase-1 (PGHS-1) was associated with increased tryptase-K(i)67-double-positive MMC in the acute stage and increased apoptosis of MMC, which led to a rapid decline in early convalescence. The eosinophils demonstrated increased expression of major basic protein (MBP), eotaxin, and CCR3, as well as increased necrotic death. The neutrophils showed enhanced alpha-defensin and lactoferrin expression in the acute phase. In contrast to adults, the pediatric patients demonstrated delayed accumulation of mast cells and eosinophils, while alpha-defensin expression persisted during convalescence. In contrast, neutrophil counts and lactoferrin expression were reduced in children compared to adults. The results suggest that children with shigellosis have a persistent activation of the innate immune response in the convalescent phase, indicating delayed elimination of Shigella antigens compared to adults.
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Affiliation(s)
- Rubhana Raqib
- International Centre for Diarrhoeal Diseases Research, Bangladesh, Dhaka, Bangladesh.
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