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Lu T, Das S, Howlader DR, Picking WD, Picking WL. Shigella Vaccines: The Continuing Unmet Challenge. Int J Mol Sci 2024; 25:4329. [PMID: 38673913 PMCID: PMC11050647 DOI: 10.3390/ijms25084329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
Shigellosis is a severe gastrointestinal disease that annually affects approximately 270 million individuals globally. It has particularly high morbidity and mortality in low-income regions; however, it is not confined to these regions and occurs in high-income nations when conditions allow. The ill effects of shigellosis are at their highest in children ages 2 to 5, with survivors often exhibiting impaired growth due to infection-induced malnutrition. The escalating threat of antibiotic resistance further amplifies shigellosis as a serious public health concern. This review explores Shigella pathology, with a primary focus on the status of Shigella vaccine candidates. These candidates include killed whole-cells, live attenuated organisms, LPS-based, and subunit vaccines. The strengths and weaknesses of each vaccination strategy are considered. The discussion includes potential Shigella immunogens, such as LPS, conserved T3SS proteins, outer membrane proteins, diverse animal models used in Shigella vaccine research, and innovative vaccine development approaches. Additionally, this review addresses ongoing challenges that necessitate action toward advancing effective Shigella prevention and control measures.
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Affiliation(s)
- Ti Lu
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - Sayan Das
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA;
| | - Debaki R. Howlader
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - William D. Picking
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
| | - Wendy L. Picking
- Department of Veterinary Pathobiology and Bond Life Science Center, University of Missouri, Columbia, MO 65201, USA; (D.R.H.); (W.D.P.)
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Chavda VP, Vuppu S, Mishra T, Kamaraj S, Sharma N, Punetha S, Sairam A, Vaghela D, Dargahi N, Apostolopoulos V. Combatting infectious diarrhea: innovations in treatment and vaccination strategies. Expert Rev Vaccines 2024; 23:246-265. [PMID: 38372023 DOI: 10.1080/14760584.2023.2295015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 12/11/2023] [Indexed: 02/20/2024]
Abstract
INTRODUCTION The escalating prevalence of infectious diseases is an important cause of concern in society. Particularly in several developing countries, infectious diarrhea poses a major problem, with a high fatality rate, especially among young children. The condition is divided into four classes, namely, acute diarrhea, invasive diarrhea, acute bloody diarrhea, and chronic diarrhea. Various pathogenic agents, such as bacteria, viruses, protozoans, and helminths, contribute to the onset of this condition. AREAS COVERED The review discusses the scenario of infectious diarrhea, the prevalent types, as well as approaches to management including preventive, therapeutic, and vaccination strategies. The vaccination techniques are extensively discussed including the available vaccines, their advantages as well as limitations. EXPERT OPINION There are several approaches available to develop new-improved vaccines. In addition, route of immunization is important and aerosols/nasal sprays, oral route, skin patches, powders, and liquid jets to minimize needles can be used. Plant-based vaccines, such as rice, might save packing and refrigeration costs by being long-lasting, non-refrigerable, and immunogenic. Future research should utilize predetermined PCR testing intervals and symptom monitoring to identify persistent pathogens after therapy and symptom remission.
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Affiliation(s)
- Vivek P Chavda
- Department of Pharmaceutics and Pharmaceutical Technology, LM College of Pharmacy, Ahmedabad, Gujarat, India
| | - Suneetha Vuppu
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Toshika Mishra
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Sathvika Kamaraj
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Nikita Sharma
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Swati Punetha
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Anand Sairam
- Department of Biotechnology, Science, Innovation, and Society Research Lab 115, Hexagon (SMV), Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Dixa Vaghela
- Pharmacy Section, L.M. College of Pharmacy, Ahmedabad, Gujarat, India
| | - Narges Dargahi
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Vasso Apostolopoulos
- Institute for Health and Sport, Victoria University, Melbourne, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Immunology Program, Sunshine Hospital Campus, Saint Albans, Victoria, Australia
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Hossain MJ, Svennerholm AM, Carlin N, D’Alessandro U, Wierzba TF. A Perspective on the Strategy for Advancing ETVAX ®, An Anti-ETEC Diarrheal Disease Vaccine, into a Field Efficacy Trial in Gambian Children: Rationale, Challenges, Lessons Learned, and Future Directions. Microorganisms 2023; 12:90. [PMID: 38257916 PMCID: PMC10819518 DOI: 10.3390/microorganisms12010090] [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] [Received: 11/15/2023] [Revised: 12/22/2023] [Accepted: 12/23/2023] [Indexed: 01/24/2024] Open
Abstract
For the first time in over 20 years, an Enterotoxigenic Escherichia coli (ETEC) vaccine candidate, ETVAX®, has advanced into a phase 2b field efficacy trial for children 6-18 months of age in a low-income country. ETVAX® is an inactivated whole cell vaccine that has gone through a series of clinical trials to provide a rationale for the design elements of the Phase 2b trial. This trial is now underway in The Gambia and will be a precursor to an upcoming pivotal phase 3 trial. To reach this point, numerous findings were brought together to define factors such as safe and immunogenic doses for children, and the possible benefit of a mucosal adjuvant, double mutant labile toxin (dmLT). Considering the promising but still underexplored potential of inactivated whole cells in oral vaccination, we present a perspective compiling key observations from past ETVAX® trials that informed The Gambian trial design. This report will update the trial's status and explore future directions for ETEC vaccine trials. Our aim is to provide not only an update on the most advanced ETEC vaccine candidate but also to offer insights beneficial for the development of other much-needed oral whole-cell vaccines against enteric and other pathogens.
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Affiliation(s)
- M. Jahangir Hossain
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, Banjul P.O. Box 273, The Gambia
| | - Ann-Mari Svennerholm
- Department of Microbiology and Immunology, Gothenburg University Research Institute (GUVAX), Gothenburg University, 40530 Gothenburg, Sweden
| | - Nils Carlin
- Scandinavian Biopharma, Industrivägen 1, 17148 Solna, Sweden
| | - Umberto D’Alessandro
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, Banjul P.O. Box 273, The Gambia
| | - Thomas F. Wierzba
- Section on Infectious Diseases, Department of Internal Medicine, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
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Toward a Shigella Vaccine: Opportunities and Challenges to Fight an Antimicrobial-Resistant Pathogen. Int J Mol Sci 2023; 24:ijms24054649. [PMID: 36902092 PMCID: PMC10003550 DOI: 10.3390/ijms24054649] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/04/2023] Open
Abstract
Shigellosis causes more than 200,000 deaths worldwide and most of this burden falls on Low- and Middle-Income Countries (LMICs), with a particular incidence in children under 5 years of age. In the last decades, Shigella has become even more worrisome because of the onset of antimicrobial-resistant strains (AMR). Indeed, the WHO has listed Shigella as one of the priority pathogens for the development of new interventions. To date, there are no broadly available vaccines against shigellosis, but several candidates are being evaluated in preclinical and clinical studies, bringing to light very important data and information. With the aim to facilitate the understanding of the state-of-the-art of Shigella vaccine development, here we report what is known about Shigella epidemiology and pathogenesis with a focus on virulence factors and potential antigens for vaccine development. We discuss immunity after natural infection and immunization. In addition, we highlight the main characteristics of the different technologies that have been applied for the development of a vaccine with broad protection against Shigella.
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MacLennan CA, Grow S, Ma LF, Steele AD. The Shigella Vaccines Pipeline. Vaccines (Basel) 2022; 10:vaccines10091376. [PMID: 36146457 PMCID: PMC9504713 DOI: 10.3390/vaccines10091376] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/06/2022] [Accepted: 08/10/2022] [Indexed: 11/22/2022] Open
Abstract
Shigella is the leading cause of global diarrheal deaths that currently lacks a licensed vaccine. Shigellosis drives antimicrobial resistance and leads to economic impact through linear growth faltering. Today, there is a robust pipeline of vaccines in clinical development which are broadly divided into parenteral glycoconjugate vaccines, consisting of O-antigen conjugated to carrier proteins, and oral live attenuated vaccines, which incorporate targeted genetic mutations seeking to optimize the balance between reactogenicity, immunogenicity and ultimately protection. Proof of efficacy has previously been shown with both approaches but for various reasons no vaccine has been licensed to date. In this report, we outline the requirements for a Shigella vaccine and describe the current pipeline in the context of the many candidates that have previously failed or been abandoned. The report refers to papers from individual vaccine developers in this special supplement of Vaccines which is focused on Shigella vaccines. Once readouts of safety and immunogenicity from current trials of lead candidate vaccines among the target population of young children in low- and middle-income countries are available, the likely time to licensure of a first Shigella vaccine will become clearer.
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Nasser A, Mosadegh M, Azimi T, Shariati A. Molecular mechanisms of Shigella effector proteins: a common pathogen among diarrheic pediatric population. Mol Cell Pediatr 2022; 9:12. [PMID: 35718793 PMCID: PMC9207015 DOI: 10.1186/s40348-022-00145-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 05/06/2022] [Indexed: 12/16/2022] Open
Abstract
Different gastrointestinal pathogens cause diarrhea which is a very common problem in children aged under 5 years. Among bacterial pathogens, Shigella is one of the main causes of diarrhea among children, and it accounts for approximately 11% of all deaths among children aged under 5 years. The case-fatality rates for Shigella among the infants and children aged 1 to 4 years are 13.9% and 9.4%, respectively. Shigella uses unique effector proteins to modulate intracellular pathways. Shigella cannot invade epithelial cells on the apical site; therefore, it needs to pass epithelium through other cells rather than the epithelial cell. After passing epithelium, macrophage swallows Shigella, and the latter should prepare itself to exhibit at least two types of responses: (I) escaping phagocyte and (II) mediating invasion of and injury to the recurrent PMN. The presence of PMN and invitation to a greater degree resulted in gut membrane injuries and greater bacterial penetration. Infiltration of Shigella to the basolateral space mediates (A) cell attachment, (B) cell entry, (C) evasion of autophagy recognition, (D) vacuole formation and and vacuole rapture, (E) intracellular life, (F) Shiga toxin, and (G) immune response. In this review, an attempt is made to explain the role of each factor in Shigella infection.
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Affiliation(s)
- Ahmad Nasser
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehrdad Mosadegh
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Taher Azimi
- Department of Bacteriology & Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - Aref Shariati
- Molecular and medicine research center, Khomein University of Medical Sciences, Khomein, Iran
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Jansen KU, Gruber WC, Simon R, Wassil J, Anderson AS. The impact of human vaccines on bacterial antimicrobial resistance. A review. ENVIRONMENTAL CHEMISTRY LETTERS 2021; 19:4031-4062. [PMID: 34602924 PMCID: PMC8479502 DOI: 10.1007/s10311-021-01274-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 07/09/2021] [Indexed: 05/07/2023]
Abstract
At present, the dramatic rise in antimicrobial resistance (AMR) among important human bacterial pathogens is reaching a state of global crisis threatening a return to the pre-antibiotic era. AMR, already a significant burden on public health and economies, is anticipated to grow even more severe in the coming decades. Several licensed vaccines, targeting both bacterial (Haemophilus influenzae type b, Streptococcus pneumoniae, Salmonella enterica serovar Typhi) and viral (influenza virus, rotavirus) human pathogens, have already proven their anti-AMR benefits by reducing unwarranted antibiotic consumption and antibiotic-resistant bacterial strains and by promoting herd immunity. A number of new investigational vaccines, with a potential to reduce the spread of multidrug-resistant bacterial pathogens, are also in various stages of clinical development. Nevertheless, vaccines as a tool to combat AMR remain underappreciated and unfortunately underutilized. Global mobilization of public health and industry resources is key to maximizing the use of licensed vaccines, and the development of new prophylactic vaccines could have a profound impact on reducing AMR.
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Affiliation(s)
| | | | - Raphael Simon
- Pfizer Vaccine Research and Development, Pearl River, NY USA
| | - James Wassil
- Pfizer Patient and Health Impact, Collegeville, PA USA
- Present Address: Vaxcyte, 353 Hatch Drive, Foster City, CA 94404 USA
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Walker R, Kaminski RW, Porter C, Choy RKM, White JA, Fleckenstein JM, Cassels F, Bourgeois L. Vaccines for Protecting Infants from Bacterial Causes of Diarrheal Disease. Microorganisms 2021; 9:1382. [PMID: 34202102 PMCID: PMC8303436 DOI: 10.3390/microorganisms9071382] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 12/22/2022] Open
Abstract
The global diarrheal disease burden for Shigella, enterotoxigenic Escherichia coli (ETEC), and Campylobacter is estimated to be 88M, 75M, and 75M cases annually, respectively. A vaccine against this target trio of enteric pathogens could address about one-third of diarrhea cases in children. All three of these pathogens contribute to growth stunting and have demonstrated increasing resistance to antimicrobial agents. Several combinations of antigens are now recognized that could be effective for inducing protective immunity against each of the three target pathogens in a single vaccine for oral administration or parenteral injection. The vaccine combinations proposed here would result in a final product consistent with the World Health Organization's (WHO) preferred product characteristics for ETEC and Shigella vaccines, and improve the vaccine prospects for support from Gavi, the Vaccine Alliance, and widespread uptake by low- and middle-income countries' (LMIC) public health stakeholders. Broadly protective antigens will enable multi-pathogen vaccines to be efficiently developed and cost-effective. This review describes how emerging discoveries for each pathogen component of the target trio could be used to make vaccines, which could help reduce a major cause of poor health, reduced cognitive development, lost economic productivity, and poverty in many parts of the world.
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Affiliation(s)
- Richard Walker
- Center for Vaccine Innovation and Access, PATH, Washington, DC 20001, USA;
| | - Robert W. Kaminski
- Department of Diarrheal Disease Research, Walter Reed Institute of Research, Silver Spring, MD 20910, USA;
| | - Chad Porter
- Enteric Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA;
| | - Robert K. M. Choy
- Center for Vaccine Innovation and Access, PATH, San Francisco, CA 94108, USA;
| | - Jessica A. White
- Center for Vaccine Innovation and Access, PATH, Seattle, WA 98121, USA; (J.A.W.); (F.C.)
| | - James M. Fleckenstein
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA;
- Medicine Service, Saint Louis VA Health Care System, St. Louis, MO 63106, USA
| | - Fred Cassels
- Center for Vaccine Innovation and Access, PATH, Seattle, WA 98121, USA; (J.A.W.); (F.C.)
| | - Louis Bourgeois
- Center for Vaccine Innovation and Access, PATH, Washington, DC 20001, USA;
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9
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de Alwis R, Liang L, Taghavian O, Werner E, The HC, Thu TNH, Duong VT, Davies DH, Felgner PL, Baker S. The identification of novel immunogenic antigens as potential Shigella vaccine components. Genome Med 2021; 13:8. [PMID: 33451348 PMCID: PMC7809897 DOI: 10.1186/s13073-020-00824-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 12/18/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Shigella is a major diarrheal pathogen for which there is presently no vaccine. Whole genome sequencing provides the ability to predict and derive novel antigens for use as vaccines. Here, we aimed to identify novel immunogenic Shigella antigens that could serve as Shigella vaccine candidates, either alone, or when conjugated to Shigella O-antigen. METHODS Using a reverse vaccinology approach, where genomic analysis informed the Shigella immunome via an antigen microarray, we aimed to identify novel immunogenic Shigella antigens. A core genome analysis of Shigella species, pathogenic and non-pathogenic Escherichia coli, led to the selection of 234 predicted immunogenic Shigella antigens. These antigens were expressed and probed with acute and convalescent serum from microbiologically confirmed Shigella infections. RESULTS Several Shigella antigens displayed IgG and IgA seroconversion, with no difference in sero-reactivity across by sex or age. IgG sero-reactivity to key Shigella antigens was observed at birth, indicating transplacental antibody transfer. Six antigens (FepA, EmrK, FhuA, MdtA, NlpB, and CjrA) were identified in in vivo testing as capable of producing binding IgG and complement-mediated bactericidal antibody. CONCLUSIONS These findings provide six novel immunogenic Shigella proteins that could serve as candidate vaccine antigens, species-specific carrier proteins, or targeted adjuvants.
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Affiliation(s)
- Ruklanthi de Alwis
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
- Viral Research and Experimental Medicine Centre, SingHealth Duke-NUS Academic Medical Centre, Singapore, Singapore
| | - Li Liang
- Vaccine Research & Development Center, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Omid Taghavian
- Vaccine Research & Development Center, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Emma Werner
- Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Hao Chung The
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Trang Nguyen Hoang Thu
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Vu Thuy Duong
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - D Huw Davies
- Vaccine Research & Development Center, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Philip L Felgner
- Vaccine Research & Development Center, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Stephen Baker
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Level 5, Jeffery Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AW, UK.
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Abstract
Enteric viral and bacterial infections continue to be a leading cause of mortality and morbidity in young children in low-income and middle-income countries, the elderly, and immunocompromised individuals. Vaccines are considered an effective and practical preventive approach against the predominantly fecal-to-oral transmitted gastroenteritis particularly in the resource-limited countries or regions where implementation of sanitation systems and supply of safe drinking water are not quickly achievable. While vaccines are available for a few enteric pathogens including rotavirus and cholera, there are no vaccines licensed for many other enteric viral and bacterial pathogens. Challenges in enteric vaccine development include immunological heterogeneity among pathogen strains or isolates, a lack of animal challenge models to evaluate vaccine candidacy, undefined host immune correlates to protection, and a low protective efficacy among young children in endemic regions. In this article, we briefly updated the progress and challenges in vaccines and vaccine development for the leading enteric viral and bacterial pathogens including rotavirus, human calicivirus, Shigella, enterotoxigenic Escherichia coli (ETEC), cholera, nontyphoidal Salmonella, and Campylobacter, and introduced a novel epitope- and structure-based vaccinology platform known as MEFA (multiepitope fusion antigen) and the application of MEFA for developing broadly protective multivalent vaccines against heterogenous pathogens.
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Affiliation(s)
- Hyesuk Seo
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
| | - Qiangde Duan
- University of Yangzhou, Institute of Comparative Medicine, Yangzhou, PR China
| | - Weiping Zhang
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA,CONTACT Weiping Zhang, University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
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11
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Kazi A, Hisyam Ismail CMK, Anthony AA, Chuah C, Leow CH, Lim BH, Banga Singh KK, Leow CY. Designing and evaluation of an antibody-targeted chimeric recombinant vaccine encoding Shigella flexneri outer membrane antigens. INFECTION GENETICS AND EVOLUTION 2020; 80:104176. [PMID: 31923724 DOI: 10.1016/j.meegid.2020.104176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 01/03/2020] [Accepted: 01/05/2020] [Indexed: 11/16/2022]
Abstract
Shigellosis is one of the most common diseases found in the developing countries, especially those countries that are prone flood. The causative agent for this disease is the Shigella species. This organism is one of the third most common enteropathogens responsible for childhood diarrhea. Since Shigella can survive gastric acidity and is an intracellular pathogen, it becomes difficult to treat. Also, uncontrolled use of antibiotics has led to development of resistant strains which poses a threat to public health. Therefore, there is a need for long term control of Shigella infection which can be achieved by designing a proper and effective vaccine. In this study, emphasis was made on designing a candidate that could elicit both B-cell and T-cell immune response. Hence B- and T-cell epitopes of outer membrane channel protein (OM) and putative lipoprotein (PL) from S. flexneri 2a were computationally predicted using immunoinformatics approach and a chimeric construct (chimeric-OP) containing the immunogenic epitopes selected from OM and PL was designed, cloned and expressed in E. coli system. The immunogenicity of the recombinant chimeric-OP was assessed using Shigella antigen infected rabbit antibody. The result showed that the chimeric-OP was a synthetic peptide candidate suitable for the development of vaccine and immunodiagnostics against Shigella infection.
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Affiliation(s)
- Ada Kazi
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Kelantan, Malaysia
| | | | - Amy Amilda Anthony
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Candy Chuah
- School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Chiuan Herng Leow
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang, Malaysia
| | - Boon Huat Lim
- School of Health Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | | | - Chiuan Yee Leow
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Kelantan, Malaysia.
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12
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Hosangadi D, Smith PG, Kaslow DC, Giersing BK. WHO consultation on ETEC and Shigella burden of disease, Geneva, 6–7th April 2017: Meeting report. Vaccine 2019; 37:7381-7390. [DOI: 10.1016/j.vaccine.2017.10.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 10/03/2017] [Indexed: 10/18/2022]
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13
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Das S, Mohakud NK, Suar M, Sahu BR. Vaccine development for enteric bacterial pathogens: Where do we stand? Pathog Dis 2019; 76:5040763. [PMID: 30052916 DOI: 10.1093/femspd/fty057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 06/19/2018] [Indexed: 01/06/2023] Open
Abstract
Gut infections triggered by pathogenic bacteria lead to most frequently occurring diarrhea in humans accounting for million deaths annually. Currently, only a few licensed vaccines are available against these pathogens for mostly travelers moving to diarrheal endemic areas. Besides commercialized vaccines, there are many formulations that are either under clinical or pre-clinical stages of development and despite several efforts to improve safety, immunogenicity and efficacy, none of them can confer long-term protective immunity, for which repeated booster doses are always recommended. Further in many countries, financial, social and political constraints have jeopardized vaccine development program against these pathogens that enforce us to gather knowledge on safety, tolerability, immunogenicity and protective efficacy regarding the same. In this review, we analyze safety and efficacy issues of vaccines against five major gut bacteria causing enteric infections. The article also simultaneously describes several barriers for vaccine development and further discusses possible strategies to enhance immunogenicity and efficacy.
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Affiliation(s)
- Susmita Das
- Infection Biology Lab, KIIT School of Biotechnology, Campus XI, Bhubaneswar 751024, India
| | - Nirmal K Mohakud
- Department of Pediatrics, Kalinga Institute of Medical Sciences, Patia, Bhubaneswar 751024, India
| | - Mrutyunjay Suar
- Infection Biology Lab, KIIT School of Biotechnology, Campus XI, Bhubaneswar 751024, India
| | - Bikash R Sahu
- Infection Biology Lab, KIIT School of Biotechnology, Campus XI, Bhubaneswar 751024, India
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14
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Kim MJ, Moon YH, Kim H, Rho S, Shin YK, Song M, Walker R, Czerkinsky C, Kim DW, Kim JO. Cross-Protective Shigella Whole-Cell Vaccine With a Truncated O-Polysaccharide Chain. Front Microbiol 2018; 9:2609. [PMID: 30429838 PMCID: PMC6220597 DOI: 10.3389/fmicb.2018.02609] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/12/2018] [Indexed: 11/13/2022] Open
Abstract
Shigella is a highly prevalent bacterium causing acute diarrhea and dysentery in developing countries. Shigella infections are treated with antibiotics but Shigellae are increasingly resistant to these drugs. Vaccination can be a countermeasure against emerging antibiotic-resistant shigellosis. Because of the structural variability in Shigellae O-antigen polysaccharides (Oag), cross-protective Shigella vaccines cannot be derived from single serotype-specific Oag. We created an attenuated Shigella flexneri 2a strain with one rather than multiple Oag units by disrupting the Oag polymerase gene (Δwzy), which broadened protective immunogenicity by exposing conserved surface proteins. Inactivated Δwzy mutant cells combined with Escherichia coli double mutant LT(R192G/L211A) as adjuvant, induced potent antibody responses to outer membrane protein PSSP-1, and type III secretion system proteins IpaB and IpaC. Intranasal immunization with the vaccine preparation elicited cross-protective immunity against S. flexneri 2a, S. flexneri 3a, S. flexneri 6, and Shigella sonnei in a mouse pneumonia model. Thus, S. flexneri 2a Δwzy represents a promising candidate strain for a universal Shigella vaccine.
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Affiliation(s)
- Min Jung Kim
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea.,Laboratory of Molecular Pathology and Cancer Genomics, College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Young-Hye Moon
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
| | - Heejoo Kim
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
| | - Semi Rho
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
| | - Young Kee Shin
- Laboratory of Molecular Pathology and Cancer Genomics, College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Manki Song
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
| | | | - Cecil Czerkinsky
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea.,Institut de Pharmacologie Moléculaire & Cellulaire CNRS-INSERM-University of Nice Sophia Antipolis, Valbonne, France
| | - Dong Wook Kim
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
| | - Jae-Ouk Kim
- Clinical Research Lab, International Vaccine Institute, Seoul National University Research Park, Seoul, South Korea
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15
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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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16
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Farhani I, Nezafat N, Mahmoodi S. Designing a Novel Multi-epitope Peptide Vaccine Against Pathogenic Shigella spp. Based Immunoinformatics Approaches. Int J Pept Res Ther 2018. [DOI: 10.1007/s10989-018-9698-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Assembly, Biochemical Characterization, Immunogenicity, Adjuvanticity, and Efficacy of Shigella Artificial Invaplex. mSphere 2018; 3:mSphere00583-17. [PMID: 29600284 PMCID: PMC5874444 DOI: 10.1128/msphere.00583-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/02/2018] [Indexed: 11/20/2022] Open
Abstract
The native Invaplex (InvaplexNAT) vaccine and adjuvant is an ion exchange-purified product derived from the water extract of virulent Shigella species. The key component of InvaplexNAT is a high-molecular-mass complex (HMMC) consisting of the Shigella lipopolysaccharide (LPS) and the invasin proteins IpaB and IpaC. To improve product purity and immunogenicity, artificial Invaplex (InvaplexAR) was developed using recombinant IpaB and IpaC proteins and purified Shigella LPS to assemble an HMMC consisting of all three components. Characterization of InvaplexAR by various methods demonstrated similar characteristics as the previously reported HMMC in InvaplexNAT. The well-defined InvaplexAR vaccine consistently contained greater quantities of IpaB, IpaC, and LPS than InvaplexNAT. InvaplexAR and InvaplexNAT immunogenicities were compared in mouse and guinea pig dose escalation studies. In both models, immunization induced antibody responses specific for InvaplexNAT and LPS while InvaplexAR induced markedly higher anti-IpaB and -IpaC serum IgG and IgA endpoint titers. In the murine model, homologous protection was achieved with 10-fold less InvaplexAR than InvaplexNAT and mice receiving InvaplexAR lost significantly less weight than mice receiving the same amount of InvaplexNAT. Moreover, mice immunized with InvaplexAR were protected from challenge with both homologous and heterologous Shigella serotypes. Guinea pigs receiving approximately 5-fold less InvaplexAR compared to cohorts immunized with InvaplexNAT were protected from ocular challenge. Furthermore, adjuvanticity previously attributed to InvaplexNAT was retained with InvaplexAR. The second-generation Shigella Invaplex vaccine, InvaplexAR, offers significant advantages over InvaplexNAT in reproducibility, flexible yet defined composition, immunogenicity, and protective efficacy. IMPORTANCEShigella species are bacteria that cause severe diarrheal disease worldwide, primarily in young children. Treatment of shigellosis includes oral fluids and antibiotics, but the high burden of disease, increasing prevalence of antibiotic resistance, and long-term health consequences clearly warrant the development of an effective vaccine. One Shigella vaccine under development is termed the invasin complex or Invaplex and is designed to drive an immune response to specific antigens of the bacteria in an effort to protect an individual from infection. The work presented here describes the production and evaluation of a new generation of Invaplex. The improved vaccine stimulates the production of antibodies in immunized mice and guinea pigs and protects these animals from Shigella infection. The next step in the product's development will be to test the safety and immune response induced in humans immunized with Invaplex.
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18
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Pastor Y, Camacho A, Gil AG, Ramos R, Ceráin ALD, Peñuelas I, Irache JM, Gamazo C. Effective protection of mice against Shigella flexneri with a new self-adjuvant multicomponent vaccine. J Med Microbiol 2017; 66:946-958. [PMID: 28721849 DOI: 10.1099/jmm.0.000527] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PURPOSE The aim of this study was to develop an immunogenic protective product against Shigella flexneri by employing a simple and safe heat treatment-based strategy. METHODOLOGY The physicochemical characteristics of naturally produced (OMV) and heat-induced (HT) outer-membrane vesicles from S. flexneri were examined, including a comparison of the protein content of the products. Toxicological and biodistribution studies, and a preliminary experiment to examine the protective effectiveness of HT in a murine model of S. flexneri infection, were also included. RESULTS This method simultaneously achieves complete bacterial inactivation and the production of the HT vaccine product, leading to a safe working process. The obtained HT complex presented a similar morphology (electron microscopy) and chemical composition to the classical OMV, although it was enriched in some immunogens, such as lipoproteins, OmpA or OmpC, among others. The HT formulation was not toxic and biodistribution studies performed in mice demonstrated that the vaccine product remained in the small intestine after nasal administration. Finally, a single dose of HT administered nasally was able to protect mice against S. flexneri 2a. CONCLUSION The convenient and safe manufacturing process, and the preliminary biological evaluation, support the use of the self-adjuvanted HT complex as a new vaccine candidate to face shigellosis. Further development is required, such as additional immune analyses, to evaluate whether this new subunit vaccine can be useful in achieving full protection against Shigella.
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Affiliation(s)
- Yadira Pastor
- Department of Microbiology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
| | - Ana Camacho
- Department of Microbiology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
| | - Ana Gloria Gil
- Department of Toxicology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
| | - Rocío Ramos
- Department of Nuclear Medicine, Clínica Universidad de Navarra, Institute of Tropical Health, University of Navarra 31008, Pamplona, Spain
| | - Adela López de Ceráin
- Department of Toxicology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
| | - Iván Peñuelas
- Department of Nuclear Medicine, Clínica Universidad de Navarra, Institute of Tropical Health, University of Navarra 31008, Pamplona, Spain
| | - Juan M Irache
- Department of Pharmaceutical Technology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
| | - Carlos Gamazo
- Department of Microbiology, Institute of Tropical Health, University of Navarra, 31008 Pamplona, Spain
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19
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Circulating Gut-Homing (α4β7+) Plasmablast Responses against Shigella Surface Protein Antigens among Hospitalized Patients with Diarrhea. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2016; 23:610-7. [PMID: 27193041 DOI: 10.1128/cvi.00205-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 05/09/2016] [Indexed: 11/20/2022]
Abstract
Developing countries are burdened with Shigella diarrhea. Understanding mucosal immune responses associated with natural Shigella infection is important to identify potential correlates of protection and, as such, to design effective vaccines. We performed a comparative analysis of circulating mucosal plasmablasts producing specific antibodies against highly conserved invasive plasmid antigens (IpaC, IpaD20, and IpaD120) and two recently identified surface protein antigens, pan-Shigella surface protein antigen 1 (PSSP1) and PSSP2, common to all virulent Shigella strains. We examined blood and stool specimens from 37 diarrheal patients admitted to the Infectious Diseases & Beliaghata General Hospital, Kolkata, India. The etiological agent of diarrhea was investigated in stool specimens by microbiological methods and real-time PCR. Gut-homing (α4β7 (+)) antibody-secreting cells (ASCs) were isolated from patient blood by means of combined magnetic cell sorting and two-color enzyme-linked immunosorbent spot (ELISPOT) assay. Overall, 57% (21 of 37) and 65% (24 of 37) of the patients were positive for Shigella infection by microbiological and real-time PCR assays, respectively. The frequency of α4β7 (+) IgG ASC responders against Ipas was higher than that observed against PSSP1 or PSSP2, regardless of the Shigella serotype isolated from these patients. Thus, α4β7 (+) ASC responses to Ipas may be considered an indirect marker of Shigella infection. The apparent weakness of ASC responses to PSSP1 is consistent with the lack of cross-protection induced by natural Shigella infection. The finding that ASC responses to IpaD develop in patients with recent-onset shigellosis indicates that such responses may not be protective or may wane too rapidly and/or be of insufficient magnitude.
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20
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Nag D, Koley H, Sinha R, Mukherjee P, Sarkar C, Withey JH, Gachhui R. Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae. Scand J Immunol 2016; 83:92-101. [PMID: 26478541 DOI: 10.1111/sji.12394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/06/2015] [Indexed: 02/03/2023]
Abstract
An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future.
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Affiliation(s)
- D Nag
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - H Koley
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - R Sinha
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - P Mukherjee
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - C Sarkar
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - J H Withey
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - R Gachhui
- Department of Life Science and Technology, Jadavpur University, Kolkata, India
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21
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Mani S, Wierzba T, Walker RI. Status of vaccine research and development for Shigella. Vaccine 2016; 34:2887-2894. [DOI: 10.1016/j.vaccine.2016.02.075] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 02/10/2016] [Indexed: 12/21/2022]
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22
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Chakraborty S, Harro C, DeNearing B, Bream J, Bauers N, Dally L, Flores J, Van de Verg L, Sack DA, Walker R. Evaluation of the Safety, Tolerability, and Immunogenicity of an Oral, Inactivated Whole-Cell Shigella flexneri 2a Vaccine in Healthy Adult Subjects. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2016; 23:315-25. [PMID: 26865592 PMCID: PMC4820506 DOI: 10.1128/cvi.00608-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/02/2016] [Indexed: 11/20/2022]
Abstract
Shigella causes high morbidity and mortality worldwide, but there is no licensed vaccine for shigellosis yet. We evaluated the safety and immunogenicity of a formalin-inactivated whole-cell Shigella flexneri2a vaccine, Sf2aWC, given orally to adult volunteers. In a double-blind, placebo-controlled trial, 82 subjects were randomized to receive three doses of vaccine in dose escalation (2.6 ± 0.8 × 10(8), × 10(9), × 10(10), and × 10(11)vaccine particles/ml). Vaccine safety was actively monitored, and antigen-specific systemic and mucosal immune responses were determined in serum, antibody in lymphocyte supernatant (ALS), and fecal samples. Cytokines were measured in the serum. Sf2aWC was well tolerated and generally safe at all four dose levels. The vaccine resulted in a dose-dependent immune response. At the highest dose, the vaccine induced robust responses to lipopolysaccharide (LPS) in both serum and ALS samples. The highest magnitude and frequency of responses occurred after the first dose in almost all samples but was delayed for IgG in serum. Fifty percent of the vaccinees had a >4-fold increase in anti-LPS fecal antibody titers. Responses to invasion plasmid antigens (Ipa) were low. The levels of interleukin-17 (IL-17), IL-2, gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and IL-10 were increased, and IL-8 was decreased immediately after first dose, but these changes were very transient. This phase I trial demonstrated that the Sf2aWC vaccine, a relatively simple vaccine concept, was safe and immunogenic. The vaccine elicited immune responses which were comparable to those induced by a live, attenuated Shigella vaccine that was protective in prior human challenge studies.
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Affiliation(s)
- Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Clayton Harro
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Barbara DeNearing
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Jay Bream
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | - Len Dally
- The EMMES Corporation, Rockville, Maryland, USA
| | | | | | - David A Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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23
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Moor K, Wotzka SY, Toska A, Diard M, Hapfelmeier S, Slack E. Peracetic Acid Treatment Generates Potent Inactivated Oral Vaccines from a Broad Range of Culturable Bacterial Species. Front Immunol 2016; 7:34. [PMID: 26904024 PMCID: PMC4749699 DOI: 10.3389/fimmu.2016.00034] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 01/24/2016] [Indexed: 12/28/2022] Open
Abstract
Our mucosal surfaces are the main sites of non-vector-borne pathogen entry, as well as the main interface with our commensal microbiota. We are still only beginning to understand how mucosal adaptive immunity interacts with commensal and pathogenic microbes to influence factors such as infectivity, phenotypic diversity, and within-host evolution. This is in part due to difficulties in generating specific mucosal adaptive immune responses without disrupting the mucosal microbial ecosystem itself. Here, we present a very simple tool to generate inactivated mucosal vaccines from a broad range of culturable bacteria. Oral gavage of 1010 peracetic acid-inactivated bacteria induces high-titer-specific intestinal IgA in the absence of any measurable inflammation or species invasion. As a proof of principle, we demonstrate that this technique is sufficient to provide fully protective immunity in the murine model of invasive non-typhoidal Salmonellosis, even in the face of severe innate immune deficiency.
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Affiliation(s)
- Kathrin Moor
- Institute for Microbiology, ETH Zürich , Zürich , Switzerland
| | - Sandra Y Wotzka
- Institute for Microbiology, ETH Zürich , Zürich , Switzerland
| | - Albulena Toska
- Institute for Microbiology, ETH Zürich , Zürich , Switzerland
| | - Médéric Diard
- Institute for Microbiology, ETH Zürich , Zürich , Switzerland
| | | | - Emma Slack
- Institute for Microbiology, ETH Zürich , Zürich , Switzerland
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24
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O'Ryan M, Vidal R, del Canto F, Carlos Salazar J, Montero D. Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part II: Vaccines for Shigella, Salmonella, enterotoxigenic E. coli (ETEC) enterohemorragic E. coli (EHEC) and Campylobacter jejuni. Hum Vaccin Immunother 2015; 11:601-19. [PMID: 25715096 DOI: 10.1080/21645515.2015.1011578] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
In Part II we discuss the following bacterial pathogens: Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic) and Campylobacter jejuni. In contrast to the enteric viruses and Vibrio cholerae discussed in Part I of this series, for the bacterial pathogens described here there is only one licensed vaccine, developed primarily for Vibrio cholerae and which provides moderate protection against enterotoxigenic E. coli (ETEC) (Dukoral(®)), as well as a few additional candidates in advanced stages of development for ETEC and one candidate for Shigella spp. Numerous vaccine candidates in earlier stages of development are discussed.
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Key Words
- CFU, colony-forming units
- CFs, colonization factors
- CT, cholera toxin
- CT-B cholera toxin B subunit
- Campylobacter
- CtdB, cytolethal distending toxin subunit B
- E. coli
- EHEC
- EPEC, enteropathogenic E. coli
- ETEC
- ETEC, enterotoxigenic E. coli
- GEMS, Global enterics multicenter study
- HUS, hemolytic uremic syndrome
- IM, intramuscular
- IgA, immunoglobulin A
- IgG, immunoglobulin G
- IgM, immunoglobulin M
- LEE, locus of enterocyte effacement
- LPS, lipopolysaccharide
- LT, heat labile toxin
- LT-B
- OMV, outer membrane vesicles
- ST, heat stable toxin
- STEC
- STEC, shigatoxin producing E. coli
- STh, human heat stable toxin
- STp, porcine heat stable toxin
- Salmonella
- Shigella
- Stx, shigatoxin
- TTSS, type III secretion system
- V. cholera
- WHO, World Health Organization
- acute diarrhea
- dmLT, double mutant heat labile toxin
- enteric pathogens
- enterohemorrhagic E. coli
- gastroenteritis
- heat labile toxin B subunit
- norovirus
- rEPA, recombinant exoprotein A of Pseudomonas aeruginosa
- rotavirus
- vaccines
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Affiliation(s)
- Miguel O'Ryan
- a Microbiology and Mycology Program; Institute of Biomedical Sciences; Faculty of Medicine; Universidad de Chile; Santiago, Chile
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25
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Hatz CFR, Bally B, Rohrer S, Steffen R, Kramme S, Siegrist CA, Wacker M, Alaimo C, Fonck VG. Safety and immunogenicity of a candidate bioconjugate vaccine against Shigella dysenteriae type 1 administered to healthy adults: A single blind, partially randomized Phase I study. Vaccine 2015; 33:4594-601. [PMID: 26162850 DOI: 10.1016/j.vaccine.2015.06.102] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 06/01/2015] [Accepted: 06/26/2015] [Indexed: 11/18/2022]
Abstract
BACKGROUND Shigellae cause severe disease in endemic countries, especially in children. Several efficacy trials have been conducted with candidate vaccines against Shigellae, but the lack of protection, the safety concerns, or manufacturing challenges hindered successful market approval. Conjugated vaccines have been shown to be safe and effective for different pathogens (i.e., Neisseria meningitidis, Shigella pneumonia, Haemophilus influenzae). The bio-conjugation technology, exploited here for the Shigella dysenteriae candidate vaccine, offers a novel and potentially simpler way to develop and produce vaccines against one of the major causes of morbidity and mortality in developing countries. METHODS A novel S. dysenteriae bioconjugate vaccine (GVXN SD133) made of the polysaccharide component of the Shigella O1 lipopolysaccharide, conjugated to the exotoxin protein A of Pseudomonas aeruginosa (EPA), was evaluated for immunogenicity and safety in healthy adults in a single blind, partially randomized Phase I study. Forty subjects (10 in each dose group; 2 μg or 10 μg with or without aluminium adjuvant) received two injections 60 days apart and were followed-up for 150 days. RESULTS Both doses and formulations were well tolerated; the safety and reactogenicity profiles were consistent with that of other conjugated vaccines, adjuvanted or not, independent of the dose and the number of injections. The GVXN SD133 vaccine elicited statistically significant O1 specific humoral responses at all time points in all vaccination groups. Between-group comparisons did not show statistically significant differences in geometric mean titers of immunoglobulin G and A at any post-vaccination time point. CONCLUSIONS This study demonstrated that the GVXN SD133 vaccine has a satisfactory safety profile. It elicited a significant humoral response to Shigella O1 polysaccharides at all doses tested. The protein carrier also elicited functional antibodies, showing the technology's advantages in preserving both sugar and conjugated protein epitopes. This trial is registered at ClinicalTrials.gov (NCT01069471).
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Affiliation(s)
- Christoph F R Hatz
- Epidemiology, Biostatistics and Prevention Institute (formerly Social and Preventive Medicine (ISPM), University of Zurich, Hirschengraben 84, Zurich 8001, Switzerland; Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland
| | - Bettina Bally
- Epidemiology, Biostatistics and Prevention Institute (formerly Social and Preventive Medicine (ISPM), University of Zurich, Hirschengraben 84, Zurich 8001, Switzerland
| | - Susanne Rohrer
- GlycoVaxyn AG, Grabenstrasse 3, Schlieren 8952, Switzerland
| | - Robert Steffen
- Epidemiology, Biostatistics and Prevention Institute (formerly Social and Preventive Medicine (ISPM), University of Zurich, Hirschengraben 84, Zurich 8001, Switzerland
| | - Stefanie Kramme
- Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland
| | - Claire-Anne Siegrist
- Center for Vaccinology, University of Geneva, CMU, 1 Michel-Servet, Geneva 4, Geneva 1211, Switzerland
| | - Michael Wacker
- GlycoVaxyn AG, Grabenstrasse 3, Schlieren 8952, Switzerland
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Nag D, Sinha R, Mitra S, Barman S, Takeda Y, Shinoda S, Chakrabarti MK, Koley H. Heat killed multi-serotype Shigella immunogens induced humoral immunity and protection against heterologous challenge in rabbit model. Immunobiology 2015. [PMID: 26210044 DOI: 10.1016/j.imbio.2015.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently we have shown the homologous protective efficacy of heat killed multi-serotype Shigella (HKMS) immunogens in a guinea pig colitis model. In our present study, we have advanced our research by immunizing rabbits with a reduced number of oral doses and evaluating the host's adaptive immune responses. The duration of immunogenicity and subsequently protective efficacy was determined against wild type heterologous Shigella strains in a rabbit luminal model. After three successive oral immunizations with HKMS immunogens, serum and lymphocyte supernatant antibody titer against the heterologous shigellae were reciprocally increased and remained at an elevated level up to 180 days. Serogroup and serotype specific O-antigen of lipopolysaccharide and immunogenic proteins of heterologous challenge strains were detected by immunoblot assay. Up-regulation of IL-12p35, IFN-γ and IL-10 mRNA expression was detected in immunized rabbit peripheral blood mononuclear cells (PBMC) after stimulation with HKMS in vitro. HKMS-specific plasma cell response was confirmed by production of a relatively higher level of HKMS-specific IgG in immunized PBMC supernatant compared to control group. Furthermore, the immunized groups of rabbits exhibited complete protection against wild type heterologous shigellae challenge. Thus HKMS immunogens induced humoral and Th1-mediated adaptive immunity and provided complete protection in a rabbit model. These immunogens could be a broad spectrum non-living vaccine candidate for human use in the near future.
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Affiliation(s)
- Dhrubajyoti Nag
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Ritam Sinha
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Soma Mitra
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Soumik Barman
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Yoshifumi Takeda
- Collaborative Research Centre of Okayama University for Infectious Diseases, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sumio Shinoda
- Collaborative Research Centre of Okayama University for Infectious Diseases, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - M K Chakrabarti
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Hemanta Koley
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India.
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Walker RI. An assessment of enterotoxigenic Escherichia coli and Shigella vaccine candidates for infants and children. Vaccine 2014; 33:954-65. [PMID: 25482842 DOI: 10.1016/j.vaccine.2014.11.049] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 11/25/2014] [Accepted: 11/27/2014] [Indexed: 02/06/2023]
Abstract
Despite improvements to water quality, sanitation, and the implementation of current prevention and treatment interventions, diarrhea remains a major cause of illness and death, especially among children less than five years of age in the developing world. Rotavirus vaccines have already begun making a real impact on diarrhea, but several more enteric vaccines will be necessary to achieve broader reductions of illness and death. Among the many causes of diarrheal disease, enterotoxigenic Escherichia coli (ETEC) and Shigella are the two most important bacterial pathogens for which there are no currently licensed vaccines. Vaccines against these two pathogens could greatly reduce the impact of disease caused by these infections. This review describes the approaches to ETEC and Shigella vaccines that are currently under development, including a range of both cellular and subunit approaches for each pathogen. In addition, the review discusses strategies for maximizing the potential benefit of these vaccines, which includes the feasibility of co-administration, consolidation, and combination of vaccine candidates, as well as issues related to effective administration of enteric vaccines to infants. Recent impact studies indicate that ETEC and Shigella vaccines could significantly benefit global public health. Either vaccine, particularly if they could be combined together or with another enteric vaccine, would be an extremely valuable tool for saving lives and promoting the health of infants and children in the developing world, as well as potentially providing protection to travelers and military personnel visiting endemic areas.
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Affiliation(s)
- Richard I Walker
- PATH, 455 Massachusetts Avenue NW, Suite 1000, Washington, DC 20001, USA.
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29
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Böhles N, Böhles N, Busch K, Busch K, Hensel M, Hensel M. Vaccines against human diarrheal pathogens: current status and perspectives. Hum Vaccin Immunother 2014; 10:1522-35. [PMID: 24861668 PMCID: PMC5396248 DOI: 10.4161/hv.29241] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 05/08/2014] [Accepted: 05/15/2014] [Indexed: 12/16/2022] Open
Abstract
Worldwide, nearly 1.7 billion people per year contract diarrheal infectious diseases (DID) and almost 760 000 of infections are fatal. DID are a major problem in developing countries where poor sanitation prevails and food and water may become contaminated by fecal shedding. Diarrhea is caused by pathogens such as bacteria, protozoans and viruses. Important diarrheal pathogens are Vibrio cholerae, Shigella spp. and rotavirus, which can be prevented with vaccines for several years. The focus of this review is on currently available vaccines against these three pathogens, and on development of new vaccines. Currently, various types of vaccines based on traditional (killed, live attenuated, toxoid or conjugate vaccines) and reverse vaccinology (DNA/mRNA, vector, recombinant subunit, plant vaccines) are in development or already available. Development of new vaccines demands high levels of knowledge, experience, budget, and time, yet promising new vaccines often fail in preclinical and clinical studies. Efficacy of vaccination also depends on the route of delivery, and mucosal immunization in particular is of special interest for preventing DID. Furthermore, adjuvants, delivery systems and other vaccine components are essential for an adequate immune response. These aspects will be discussed in relation to the improvement of existing and development of new vaccines against DID.
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Affiliation(s)
| | | | | | | | - Michael Hensel
- Abt. Mikrobiologie; Universität Osnabrück; Osnabrück, Germany
| | - Michael Hensel
- Abt. Mikrobiologie; Universität Osnabrück; Osnabrück, Germany
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Zaidi MB, Estrada-García T. Shigella: A Highly Virulent and Elusive Pathogen. CURRENT TROPICAL MEDICINE REPORTS 2014; 1:81-87. [PMID: 25110633 DOI: 10.1007/s40475-014-0019-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Despite a significant decrease in Shigella-related mortality, shigellosis continues to carry a significant burden of disease worldwide, particularly in Asia and Africa. Shigella is a highly virulent pathogen comprised of four major species with numerous subtypes. Shigella dysenteriae and Shigella flexneri infections are predominant in resource-limited settings. Clinical presentations range from mild watery diarrhea to severe dysentery with systemic complications such as electrolyte imbalance, seizures and hemolytic uremic syndrome. S. dysenteriae subtype 1, the producer of Shiga toxin, causes the most severe illness and highest mortality. Susceptible strains of Shigella may be effectively treated with inexpensive oral antibiotics such as ampicillin or trimethoprim-sulfamethoxazole. Unfortunately, multidrug resistant strains have emerged that have rendered most antibiotics, including fluoroquinolones and extended-spectrum cephalosporins, ineffective. Management and prevention of shigellosis represents a major public health challenge. The development of an effective vaccine is urgently needed to decrease its global impact.
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Affiliation(s)
- Mussaret Bano Zaidi
- Microbiology Research Laboratory, Hospital General O'Horan, Av. Itzaes x Jacinto Canek, C.P. 97000 Mérida, Mexico. Phone and fax: +52-(999) 923-8673, ; Infectious Diseases Research Unit, Hospital Regional de Alta Especialidad de la Península de Yucatán, Km. 8.5 Carr. Merida-Cholul S/N, Col. Maya, C.P. 97134, Merida, Mexico
| | - Teresa Estrada-García
- Department of Molecular Biomedicine, CINVESTAV-IPN, Av. Instituto Politecnico Nacional 2508, San Pedro Zacatenco, C.P. 07360, Mexico City, Mexico. ,
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Abstract
Several live-attenuated Shigella vaccines, with well-defined mutations in specific genes, have shown great promise in eliciting significant immune responses when given orally to volunteers. These responses have been measured by evaluating antibody-secreting cells, serum antibody levels and fecal immunoglobulin A to bacterial lipopolysaccharide and to individual bacterial invasion plasmid antigens. In this review, data collected from volunteer trials with live Shigella vaccines from three different research groups are described. The attenuating features of the bacterial strains, as well as the immune response following the use of different dosing regimens, are also described. The responses obtained with each vaccine strain are compared with data obtained from challenge trials using wild-type Shigella strains. Although the exact correlates of protection have not been found, some consensus may be derived as to what may constitute a protective immune response. Future directions in the field of live Shigella vaccines are also discussed.
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Affiliation(s)
- Malabi M Venkatesan
- Division of Bacterial and Rickettsial Diseases, Walter Reed Army Institute of Research, 503 Robert Forney Drive, Room 3s12, Silver Spring, MD 20910, USA.
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Development and preclinical evaluation of a trivalent, formalin-inactivated Shigella whole-cell vaccine. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:366-82. [PMID: 24403527 DOI: 10.1128/cvi.00683-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Studies were undertaken to manufacture a multivalent Shigella inactivated whole-cell vaccine that is safe, effective, and inexpensive. By using several formalin concentrations, temperatures, and incubation periods, an optimized set of inactivation conditions was established for Shigella flexneri 2a, S. sonnei, and S. flexneri 3a to produce inactivated whole cells expressing a full repertoire of Ipa proteins and lipopolysaccharide (LPS). The inactivation conditions selected were treatment with 0.2% formalin (S. flexneri 2a and 3a) or 0.6% formalin (S. sonnei) for 48 h at 25°C. Vaccine formulations prepared under different inactivation conditions, in different doses (10E5, 10E7, and 10E9 cells), and with or without the inclusion of double-mutant heat-labile toxin (dmLT) were evaluated in mice. Two intranasal immunizations with ≥10E7 inactivated whole cells resulted in high levels of anti-Invaplex and moderate levels of LPS-specific IgG and IgA in serum and in lung and intestinal wash samples. Addition of dmLT to the vaccine formulations did not significantly enhance humoral immunogenicity. Minimal humoral responses for IpaB, IpaC, or IpaD were detected after immunization with inactivated whole Shigella cells regardless of the vaccine inactivation conditions. In guinea pigs, monovalent formulations of S. flexneri 2a of 3a or S. sonnei consisting of 10E8, 10E9, or 10E10 cells were protective in a keratoconjunctivitis assay. A trivalent formulation provided protection against all three serotypes (S. flexneri 2a, P = 0.018; S. flexneri 3a, P = 0.04; S. sonnei, P < 0.0001). The inactivated Shigella whole-cell vaccine approach incorporates an uncomplicated manufacturing process that is compatible with multivalency and the future development of a broadly protective Shigella vaccine.
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Barman S, Koley H, Ramamurthy T, Chakrabarti MK, Shinoda S, Nair GB, Takeda Y. Protective immunity by oral immunization with heat-killedShigellastrains in a guinea pig colitis model. Microbiol Immunol 2013; 57:762-71. [DOI: 10.1111/1348-0421.12095] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 08/28/2013] [Accepted: 08/31/2013] [Indexed: 01/29/2023]
Affiliation(s)
- Soumik Barman
- National Institute of Cholera and Enteric Diseases; P-33, C.I.T. Road, Scheme XM
| | - Hemanta Koley
- National Institute of Cholera and Enteric Diseases; P-33, C.I.T. Road, Scheme XM
| | | | | | - Sumio Shinoda
- Collaborative Research Center of Okayama University for Infectious Diseases in India; 67 Dr. S. C. Banerjee Road, ID Hospital Campus, Beliaghata Kolkata 700 010
| | - Gopinath Balakrish Nair
- Translational Health Science and Technology Institute; Plot No. 496, Phase-III, Udyog Vihar Gurgaon Haryana 122 016 India
| | - Yoshifumi Takeda
- Collaborative Research Center of Okayama University for Infectious Diseases in India; 67 Dr. S. C. Banerjee Road, ID Hospital Campus, Beliaghata Kolkata 700 010
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34
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Ashkenazi S, Cohen D. An update on vaccines against Shigella. THERAPEUTIC ADVANCES IN VACCINES 2013; 1:113-23. [PMID: 24757519 PMCID: PMC3967666 DOI: 10.1177/2051013613500428] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Despite intensive research efforts for more than 60 years, utilizing diverse vaccine strategies, a safe and efficacious vaccine against shigellosis is not available yet. We are currently witnessing innovative approaches based on elucidation of the virulence mechanisms of Shigella, understanding the immune response to the pathogen and progress in molecular technology for developing Shigella vaccines. It is hoped that these will lead to a licensed effective Shigella vaccine to protect humans against the significant worldwide morbidity and mortality caused by this microorganism.
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Affiliation(s)
- Shai Ashkenazi
- Department of Pediatrics A, Schneider Children's Medical Center, 14 Kaplan Street, Petach Tikva 49202, Israel
| | - Dani Cohen
- School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Israel
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35
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Camacho AI, Irache JM, Gamazo C. Recent progress towards development of a Shigella vaccine. Expert Rev Vaccines 2013; 12:43-55. [PMID: 23256738 DOI: 10.1586/erv.12.135] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The burden of dysentery due to shigellosis among children in the developing world is still a major concern. A safe and efficacious vaccine against this disease is a priority, since no licensed vaccine is available. This review provides an update of vaccine achievements focusing on subunit vaccine strategies and the forthcoming strategies surrounding this approach. In particular, this review explores several aspects of the pathogenesis of shigellosis and the elicited immune response as being the basis of vaccine requirements. The use of appropriate Shigella antigens, together with the right adjuvants, may offer safety, efficacy and more convenient delivery methods for massive worldwide vaccination campaigns.
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Heine SJ, Diaz-McNair J, Martinez-Becerra FJ, Choudhari SP, Clements JD, Picking WL, Pasetti MF. Evaluation of immunogenicity and protective efficacy of orally delivered Shigella type III secretion system proteins IpaB and IpaD. Vaccine 2013; 31:2919-29. [PMID: 23644075 DOI: 10.1016/j.vaccine.2013.04.045] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/17/2013] [Accepted: 04/19/2013] [Indexed: 10/26/2022]
Abstract
Shigella spp. are food- and water-borne pathogens that cause shigellosis, a severe diarrheal and dysenteric disease that is associated with a high morbidity and mortality in resource-poor countries. No licensed vaccine is available to prevent shigellosis. We have recently demonstrated that Shigella invasion plasmid antigens (Ipas), IpaB and IpaD, which are components of the bacterial type III secretion system (TTSS), can prevent infection in a mouse model of intranasal immunization and lethal pulmonary challenge. Because they are conserved across Shigella spp. and highly immunogenic, these proteins are excellent candidates for a cross-protective vaccine. Ideally, such a vaccine could be administered to humans orally to induce mucosal and systemic immunity. In this study, we investigated the immunogenicity and protective efficacy of Shigella IpaB and IpaD administered orally with a double mutant of the Escherichia coli heat labile toxin (dmLT) as a mucosal adjuvant. We characterized the immune responses induced by oral vs. intranasal immunization and the protective efficacy using a mouse pulmonary infection model. Serum IgG and fecal IgA against IpaB were induced after oral immunization. These responses, however, were lower than those obtained after intranasal immunization despite a 100-fold dosage increase. The level of protection induced by oral immunization with IpaB and IpaD was 40%, while intranasal immunization resulted in 90% protective efficacy. IpaB- and IpaD-specific IgA antibody-secreting cells in the lungs and spleen and T-cell-derived IL-2, IL-5, IL-17 and IL-10 were associated with protection. These results demonstrate the immunogenicity of orally administered IpaB and IpaD and support further studies in humans.
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Affiliation(s)
- Shannon J Heine
- Center for Vaccine Development and Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States
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37
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Camacho A, Souza-Rebouças J, Irache J, Gamazo C. Towards a non-living vaccine against Shigella flexneri: From the inactivation procedure to protection studies. Methods 2013; 60:264-8. [DOI: 10.1016/j.ymeth.2012.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 09/22/2012] [Indexed: 11/27/2022] Open
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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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39
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Infections intestinales aiguës : vaccins actuels et futurs. Presse Med 2013; 42:93-101. [DOI: 10.1016/j.lpm.2012.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 10/04/2012] [Indexed: 01/06/2023] Open
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40
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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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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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Barnoy S, Jeong KI, Helm RF, Suvarnapunya AE, Ranallo RT, Tzipori S, Venkatesan MM. Characterization of WRSs2 and WRSs3, new second-generation virG(icsA)-based Shigella sonnei vaccine candidates with the potential for reduced reactogenicity. Vaccine 2009; 28:1642-54. [PMID: 19932216 DOI: 10.1016/j.vaccine.2009.11.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 09/02/2009] [Accepted: 11/03/2009] [Indexed: 11/28/2022]
Abstract
Live, attenuated Shigella vaccine candidates, such as Shigella sonnei strain WRSS1, Shigella flexneri 2a strain SC602, and Shigella dysenteriae 1 strain WRSd1, are attenuated principally by the loss of the VirG(IcsA) protein. These candidates have proven to be safe and immunogenic in volunteer trials and in one study, efficacious against shigellosis. One drawback of these candidate vaccines has been the reactogenic symptoms of fever and diarrhea experienced by the volunteers, that increased in a dose-dependent manner. New, second-generation virG(icsA)-based S. sonnei vaccine candidates, WRSs2 and WRSs3, are expected to be less reactogenic while retaining the ability to generate protective levels of immunogenicity seen with WRSS1. Besides the loss of VirG(IcsA), WRSs2 and WRSs3 also lack plasmid-encoded enterotoxin ShET2-1 and its paralog ShET2-2. WRSs3 further lacks MsbB2 that reduces the endotoxicity of the lipid A portion of the bacterial LPS. Studies in cell cultures and in gnotobiotic piglets demonstrate that WRSs2 and WRSs3 have the potential to cause less diarrhea due to loss of ShET2-1 and ShET2-2 as well as alleviate febrile symptoms by loss of MsbB2. In guinea pigs, WRSs2 and WRSs3 were as safe, immunogenic and efficacious as WRSS1.
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Affiliation(s)
- S Barnoy
- Division of Bacterial & Rickettsial Diseases, Walter Reed Army Institute of Research 503, Robert Grant Avenue, Silver Spring, MD 208914, United States
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The efficacy and immunogenicity of a live transconjugant hybrid strain of Shigella dysenteriae type 1 in two animal models. World J Microbiol Biotechnol 2008. [DOI: 10.1007/s11274-008-9937-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
PURPOSE OF REVIEW Shigellosis, a major form of bacillary dysentery, is caused by infection with Shigella organisms. In poor countries, Shigella-caused dysentery is endemic and causes an estimated 163 million illness episodes annually and more than one million deaths. Although several strategies have been used to develop vaccines targeting shigellosis, none has been licensed for use outside China. Owing to the wide range of Shigella serotypes and subtypes, there is a need for a multivalent vaccine representing prevalent species and serotypes. RECENT FINDINGS Vaccine development has been limited by the lack of a suitable animal model for vaccine testing. This review discusses the most advanced strategies for Shigella vaccine development including live attenuated, conjugate, broad spectrum, and proteosome-based vaccines and describes current animal models under study. SUMMARY The greatest barrier to the use of vaccine against shigellosis in developing areas is poor immune responses to oral vaccines in children who have minimal maternal antibodies. Clinical studies of promising shigellosis vaccine candidates are urgently needed after confirmation of safety, immunogenicity, and protection in volunteer challenge models.
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Affiliation(s)
- Mi-Na Kweon
- Mucosal Immunology Section, Laboratory Science Division, International Vaccine Institute, Kwanak-Gu, Seoul, Korea.
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45
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Petri WA, Miller M, Binder HJ, Levine MM, Dillingham R, Guerrant RL. Enteric infections, diarrhea, and their impact on function and development. J Clin Invest 2008; 118:1277-90. [PMID: 18382740 DOI: 10.1172/jci34005] [Citation(s) in RCA: 281] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Enteric infections, with or without overt diarrhea, have profound effects on intestinal absorption, nutrition, and childhood development as well as on global mortality. Oral rehydration therapy has reduced the number of deaths from dehydration caused by infection with an enteric pathogen, but it has not changed the morbidity caused by such infections. This Review focuses on the interactions between enteric pathogens and human genetic determinants that alter intestinal function and inflammation and profoundly impair human health and development. We also discuss specific implications for novel approaches to interventions that are now opened by our rapidly growing molecular understanding.
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Affiliation(s)
- William A Petri
- Center for Global Health, Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA
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46
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Riddle MS, Tribble DR. Reaching a consensus on management practices and vaccine development targets for mitigation of infectious diarrhoea among deployed US military forces. J Eval Clin Pract 2008; 14:266-74. [PMID: 18284518 DOI: 10.1111/j.1365-2753.2007.00848.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
RATIONALE, AIMS AND OBJECTIVES This study is part of a research effort to identify and quantify factors related to the cost-effectiveness of a vaccine acquisition strategy to reduce the burden of infectious diarrhoea on US military personnel deployed overseas. Where evidence is lacking in the scientific literature, or considerable uncertainty exists, it is often necessary to develop best estimates with ranges of certainty. To this end, a modified 'Delphi' survey technique to obtain the best estimates for uncertain parameters including clinical care-seeking behaviour for acute diarrhoea, routine diarrhoea management in a deployed setting, and vaccine development time frames and costs were developed from a diverse panel of experts. METHODS The study was conducted in three survey iterations. During each iteration, participants were contacted and given 2-3 weeks to complete a web-based survey designed to ascertain estimates, ranges of variability, and level of certainty for these estimates. RESULTS In all, 25 of 43 solicited experts agreed to participate in the study. These included three (12%) experts who identified themselves primarily as being currently involved in Vaccine Industry, six (24%) Academic/Military Diarrheal Vaccine Development, five (20%) Military Product Acquisition, five (20%) Military Preventive Medicine, two (8%) Tropical/Travel Medicine and four (16%) Military Clinical Infectious Disease. Management practices in deployed military populations (for both provider and self-treatment) were consistent with recently published literature. Similar target time frames for vaccine licensure were established for Enterotoxigenic E. coli, Campylobacter, Shigella and Norovirus of around 9-11 years. Targets for vaccine efficacy appear to be lower than currently licensed travel vaccines (60-80%), and there was consensus on more conservative adverse event rates. CONCLUSIONS These data should prove useful to researchers and policy makers working in the area of vaccine acquisition for the US military and provide continued information on the gap in optimal travellers' diarrhoea management practices in a deployed setting.
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Affiliation(s)
- Mark S Riddle
- Infections Diseases Clinical Research Program, Preventive Medicine and Biometrics Department, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
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47
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Abstract
The need for minimally invasive delivery methods is urgent. As the number of registered vaccines increases, so does the number of injections. The use of sharps can be unsafe and needle immunisation is less suitable for mass immunisations during emergencies such as pandemics or bioterrorist attacks. The approach of combining vaccines has limitations due to high development costs, risk of pharmaceutical or immunological interference and economic risks. Advancements in the development of alternatives to injection with syringes and needles are discussed in this paper, and include: mucosal vaccination, injection without needles and vaccine delivery via the skin.
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Affiliation(s)
- Gideon Kersten
- Netherlands Vaccine Institute, Research and Development Department, PO Box 457, 3720 Al Bilthoven, The Netherlands.
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48
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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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49
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Walker RI, Steele D, Aguado T. Analysis of strategies to successfully vaccinate infants in developing countries against enterotoxigenic E. coli (ETEC) disease. Vaccine 2006; 25:2545-66. [PMID: 17224212 DOI: 10.1016/j.vaccine.2006.12.028] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Accepted: 12/12/2006] [Indexed: 12/30/2022]
Abstract
Enterotoxigenic Escherichia coli (ETEC) is the most common bacterial cause of diarrhoea in the world, annually affecting up to 400,000,000 children under 5 years of age living in developing countries (DCs). Although ETEC possesses numerous antigens, the relatively conserved colonization factor (CF) antigens and the heat labile enterotoxin (LT) have been associated with protection and most vaccine candidates have exploited these antigens. A safe and effective vaccine against ETEC is a feasible goal as supported by the acquisition of protective immunity. The success of an ETEC vaccine targeting infants and children in DCs will depend on a combination of maximally antigenic vaccine preparations and regimens for their delivery which will produce optimal immune responses to these antigens. Vaccine candidates having a high priority for accelerated development and clinical testing for eventual use in infants would include inactivated ETEC or Shigella hybrids expressing ETEC antigens as well as attenuated ETEC strains which express the major CF antigens and LT toxin B-subunit, as well as attenuated Shigella, Vibrio cholerae and Salmonella typhi hybrids engineered to deliver antigens of ETEC. Candidates for an ETEC vaccine would have to meet the minimal requirement of providing at least 50% protection against severe disease in DCs during the first 2 years of life. The critical roadblock to achieving this goal has not been the science as much as the lack of a sufficiently funded and focused effort to bring it to realization. However, a Product Development Partnership to overcome this hurdle could accelerate the time lines towards when control of ETEC disease in DCs is substantially closer.
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Affiliation(s)
- Richard I Walker
- Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20851-1448, USA.
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50
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Oaks EV, Turbyfill KR. Development and evaluation of a Shigella flexneri 2a and S. sonnei bivalent invasin complex (Invaplex) vaccine. Vaccine 2005; 24:2290-301. [PMID: 16364513 DOI: 10.1016/j.vaccine.2005.11.040] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2005] [Revised: 10/24/2005] [Accepted: 11/18/2005] [Indexed: 11/19/2022]
Abstract
Over 160 million cases of shigellosis occur annually worldwide, with the two most prevalent species being Shigella flexneri and S. sonnei. Protective immunity against Shigella infection is primarily directed at the lipopolysaccharide (LPS) of the homologous serotype, so it may be necessary to combine monovalent vaccines for multiple Shigella serotypes to construct a multivalent vaccine against predominant serotypes. Recently, we described a subcellular vaccine isolated from virulent S. flexneri, consisting of proteins (including the invasins IpaB and IpaC) and LPS, that protected mice and guinea pigs from homologous challenge. In the present study, a bivalent Invaplex vaccine consisting of S. flexneri 2a and S. sonnei Invaplex was used to intranasally immunize mice and guinea pigs to determine the bivalent vaccine's immunogenicity and protective capacity against challenge with either strain. Mice and guinea pigs immunized with the bivalent S. flexneri 2a/S. sonnei Invaplex vaccine produced serum IgA and IgG antibodies to S. flexneri LPS, S. sonnei LPS, the homologous Invaplex and the water extract antigens (invasins) as determined by ELISA. The immune responses in animals immunized with the bivalent vaccine were similar to responses in animals immunized with the monovalent Invaplex vaccines. Mice and guinea pigs immunized with the bivalent vaccine were protected from a lethal lung challenge (mice, P<0.001) or severe keratoconjunctivitis (guinea pigs, P< or = 0.002) after challenge with either S. flexneri 2a or S. sonnei. Animals immunized with monovalent Invaplex vaccines were protected (P<0.001) against the homologous agent at levels comparable to the bivalent vaccine. After challenge, immunized animals demonstrated boosts in antibody titers to LPS, water extract antigens and Invaplex. These studies indicate that the subcellular Invaplex vaccine will be readily adaptable to a multivalent vaccine approach for shigellosis.
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Affiliation(s)
- Edwin V Oaks
- Walter Reed Army Institute of Research, Silver Spring, MD 20910-7510, USA.
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