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Pajuelo MJ, Noazin S, Cabrera L, Toledo A, Velagic M, Arias L, Ochoa M, Moulton LH, Saito M, Gilman RH, Chakraborty S. Epidemiology of enterotoxigenic Escherichia coli and impact on the growth of children in the first two years of life in Lima, Peru. Front Public Health 2024; 12:1332319. [PMID: 38584932 PMCID: PMC10995271 DOI: 10.3389/fpubh.2024.1332319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 03/11/2024] [Indexed: 04/09/2024] Open
Abstract
Background Enterotoxigenic E. coli (ETEC) is a leading cause of diarrheal morbidity and mortality in children, although the data on disease burden, epidemiology, and impact on health at the community level are limited. Methods In a longitudinal birth cohort study of 345 children followed until 24 months of age in Lima, Peru, we measured ETEC burden in diarrheal and non-diarrheal samples using quantitative PCR (LT, STh, and STp toxin genes), studied epidemiology and measured anthropometry in children. Results About 70% of children suffered from one or more ETEC diarrhea episodes. Overall, the ETEC incidence rate (IR) was 73 per 100 child-years. ETEC infections began early after birth causing 10% (8.9-11.1) ETEC-attributable diarrheal burden at the population level (PAF) in neonates and most of the infections (58%) were attributed to ST-ETEC [PAF 7.9% (1.9-13.5)] and LT + ST-ETEC (29%) of which all the episodes were associated with diarrhea. ETEC infections increased with age, peaking at 17% PAF (4.6-27.7%; p = 0.026) at 21 to 24 months. ST-ETEC was the most prevalent type (IR 32.1) with frequent serial infections in a child. The common colonization factors in ETEC diarrhea cases were CFA/I, CS12, CS21, CS3, and CS6, while in asymptomatic ETEC cases were CS12, CS6 and CS21. Only few (5.7%) children had repeated infections with the same combination of ETEC toxin(s) and CFs, suggested genotype-specific immunity from each infection. For an average ETEC diarrhea episode of 5 days, reductions of 0.060 weight-for-length z-score (0.007 to 0.114; p = 0.027) and 0.061 weight-for-age z-score (0.015 to 0.108; p = 0.009) were noted in the following 30 days. Conclusion This study showed that ETEC is a significant pathogen in Peruvian children who experience serial infections with multiple age-specific pathotypes, resulting in transitory growth impairment.
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Affiliation(s)
- Monica J. Pajuelo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Sassan Noazin
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | | | - Angie Toledo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mirza Velagic
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Lucero Arias
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mayra Ochoa
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Lawrence H. Moulton
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Mayuko Saito
- Department of Virology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Robert H. Gilman
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Subhra Chakraborty
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
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Chakraborty S, Johura FT, Sultana M, Zhang X, Sadique A, George CM, Monira S, Sack DA, Sack RB, Alam M. Epidemiology of Enterotoxigenic Escherichia coli among Children and Adults Seeking Care at Hospitals in Two Geographically Distinct Rural Areas in Bangladesh. Microorganisms 2024; 12:359. [PMID: 38399763 PMCID: PMC10891752 DOI: 10.3390/microorganisms12020359] [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: 12/21/2023] [Revised: 02/01/2024] [Accepted: 02/03/2024] [Indexed: 02/25/2024] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) infections undeniably continue to have substantial morbidity and mortality in younger children; however, limited data are available on the disease burden of older children and adults and on ETEC epidemiology by geographical location at the subnational level. Facility-based surveillance over the years was established to identify patients with ETEC diarrhea in two geographically distinct areas in rural Bangladesh, Chhatak in the north and Mathbaria in the southern coastal area. ETEC was highly prevalent in both areas, while the proportions, toxin types and colonization factors varied by location, season and age groups. Children < 5 years old and adults between 20 and 60 years old were at the highest risk of ETEC diarrhea which required urgent care. This study underscores the importance of capturing subnational and seasonal variations in ETEC epidemiology. ETEC vaccine developers and public health stakeholders may need to target adults between 20 and 60 years of age in addition to young children as new vaccines currently under development become licensed and introduction begins.
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Affiliation(s)
- Subhra Chakraborty
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
| | - Fatema-Tuz Johura
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
- International Centre for Diarrhoeal Disease Research, Dhaka 1212, Bangladesh; (M.S.); (A.S.); (S.M.); (M.A.)
| | - Marzia Sultana
- International Centre for Diarrhoeal Disease Research, Dhaka 1212, Bangladesh; (M.S.); (A.S.); (S.M.); (M.A.)
| | - Xueyan Zhang
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
| | - Abdus Sadique
- International Centre for Diarrhoeal Disease Research, Dhaka 1212, Bangladesh; (M.S.); (A.S.); (S.M.); (M.A.)
| | - Christine M. George
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
| | - Shirajum Monira
- International Centre for Diarrhoeal Disease Research, Dhaka 1212, Bangladesh; (M.S.); (A.S.); (S.M.); (M.A.)
| | - David A. Sack
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
| | - Richard Bradley Sack
- Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; (F.-T.J.); (X.Z.); (C.M.G.); (D.A.S.); (R.B.S.)
| | - Munirul Alam
- International Centre for Diarrhoeal Disease Research, Dhaka 1212, Bangladesh; (M.S.); (A.S.); (S.M.); (M.A.)
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Zhou S, Yu KOA, Mabrouk MT, Jahagirdar D, Huang WC, Guerra JA, He X, Ortega J, Poole ST, Hall ER, Gomez-Duarte OG, Maciel M, Lovell JF. Antibody induction in mice by liposome-displayed recombinant enterotoxigenic Escherichia coli (ETEC) colonization antigens. Biomed J 2023; 46:100588. [PMID: 36925108 PMCID: PMC10711177 DOI: 10.1016/j.bj.2023.03.001] [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: 06/21/2022] [Revised: 03/03/2023] [Accepted: 03/06/2023] [Indexed: 03/17/2023] Open
Abstract
BACKGROUND Enterotoxigenic Escherichia coli (ETEC) strains cause infectious diarrhea and colonize host intestine epithelia via surface-expressed colonization factors. Colonization factor antigen I (CFA/I), a prevalent ETEC colonization factor, is a vaccine target since antibodies directed to this fimbria can block ETEC adherence and prevent diarrhea. METHODS Two recombinant antigens derived from CFA/I were investigated with a vaccine adjuvant system that displays soluble antigens on the surface of immunogenic liposomes. The first antigen, CfaEB, is a chimeric fusion protein comprising the minor (CfaE) and major (CfaB) subunits of CFA/I. The second, CfaEad, is the adhesin domain of CfaE. RESULTS Owing to their His-tag, recombinant CfaEB and CfaEad, spontaneously bound upon admixture with nanoliposomes containing cobalt-porphyrin phospholipid (CoPoP), as well as a synthetic monophosphoryl lipid A (PHAD) adjuvant. Intramuscular immunization of mice with sub-microgram doses CfaEB or CfaEad admixed with CoPoP/PHAD liposomes elicited serum IgG and intestinal IgA antibodies. The smaller CfaEad antigen benefitted more from liposome display. Serum and intestine antibodies from mice immunized with liposome-displayed CfaEB or CfaEad recognized native CFA/I fimbria as evidenced by immunofluorescence and hemagglutination inhibition assays using the CFA/I-expressing H10407 ETEC strain. CONCLUSION These data show that colonization factor-derived recombinant ETEC antigens exhibit immunogenicity when delivered in immunogenic particle-based formulations.
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Affiliation(s)
- Shiqi Zhou
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA
| | - Karl O A Yu
- Division of Pediatrics Infectious Diseases, Department of Pediatrics, University at Buffalo, Buffalo, NY, USA
| | - Moustafa T Mabrouk
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA
| | | | - Wei-Chiao Huang
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA
| | - Julio A Guerra
- Division of Pediatrics Infectious Diseases, Department of Pediatrics, University at Buffalo, Buffalo, NY, USA
| | - Xuedan He
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA
| | - Joaquin Ortega
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - Steven T Poole
- Naval Medical Research Center, Silver Spring, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Eric R Hall
- Naval Medical Research Center, Silver Spring, MD, USA
| | - Oscar G Gomez-Duarte
- Division of Pediatrics Infectious Diseases, Department of Pediatrics, University at Buffalo, Buffalo, NY, USA
| | - Milton Maciel
- Naval Medical Research Center, Silver Spring, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA; Department of Microbiology and Immunology, Uniformed Services University Health System, Bethesda, MD, USA.
| | - Jonathan F Lovell
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA.
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Khalil I, Anderson JD, Bagamian KH, Baqar S, Giersing B, Hausdorff WP, Marshall C, Porter CK, Walker RI, Bourgeois AL. Vaccine value profile for enterotoxigenic Escherichia coli (ETEC). Vaccine 2023; 41 Suppl 2:S95-S113. [PMID: 37951695 DOI: 10.1016/j.vaccine.2023.02.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 11/28/2022] [Accepted: 02/05/2023] [Indexed: 11/14/2023]
Abstract
Enterotoxigenic Escherichia coli (ETEC) is one of the leading bacterial causes of diarrhoea, especially among children in low-resource settings, and travellers and military personnel from high-income countries. WHO's primary strategic goal for ETEC vaccine development is to develop a safe, effective, and affordable ETEC vaccine that reduces mortality and morbidity due to moderate-to-severe diarrhoeal disease in infants and children under 5 years of age in LMICs, as well as the long-term negative health impact on infant physical and cognitive development resulting from infection with this enteric pathogen. An effective ETEC vaccine will also likely reduce the need for antibiotic treatment and help limit the further emergence of antimicrobial resistance bacterial pathogens. The lead ETEC vaccine candidate, ETVAX, has shown field efficacy in travellers and has moved into field efficacy testing in LMIC infants and children. A Phase 3 efficacy study in LMIC infants is projected to start in 2024 and plans for a Phase 3 trial in travellers are under discussion with the U.S. FDA. Licensing for both travel and LMIC indications is projected to be feasible in the next 5-8 years. Given increasing recognition of its negative impact on child health and development in LMICs and predominance as the leading etiology of travellers' diarrhoea (TD), a standalone vaccine for ETEC is more cost-effective than vaccines targeting other TD pathogens, and a viable commercial market also exists. In contrast, combination of an ETEC vaccine with other vaccines for childhood pathogens in LMICs would maximize protection in a more cost-effective manner than a series of stand-alone vaccines. This 'Vaccine Value Profile' (VVP) for ETEC is intended to provide a high-level, holistic assessment of available data to inform the potential public health, economic and societal value of pipeline vaccines and vaccine-like products. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public private partnerships, and multi-lateral organizations. All contributors have extensive expertise on various elements of the ETEC VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.
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Affiliation(s)
- Ibrahim Khalil
- Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - John D Anderson
- Bagamian Scientific Consulting, LLC, Gainesville, FL 32601, USA; Office of Health Affairs, West Virginia University, Morgantown, WV 26505, USA
| | - Karoun H Bagamian
- Bagamian Scientific Consulting, LLC, Gainesville, FL 32601, USA; Department of Environmental and Global Health, University of Florida, Gainesville, FL 32603, USA
| | - Shahida Baqar
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Birgitte Giersing
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization (WHO), Geneva, Switzerland
| | - William P Hausdorff
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001 USA; Faculty of Medicine, Université Libre de Bruxelles, Brussels 1070, Belgium
| | - Caroline Marshall
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization (WHO), Geneva, Switzerland
| | - Chad K Porter
- Directorate for DoD Infectious Diseases Research, Naval Medical Research Command, Silver Spring, MD 20190, USA
| | - Richard I Walker
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001 USA
| | - A Louis Bourgeois
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001 USA
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5
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Girardi P, Bhuiyan TR, Lundin SB, Harutyunyan S, Neuhauser I, Khanam F, Nagy G, Szijártó V, Henics T, Nagy E, Harandi AM, Qadri F. Anti-Toxin Responses to Natural Enterotoxigenic Escherichia coli (ETEC) Infection in Adults and Children in Bangladesh. Microorganisms 2023; 11:2524. [PMID: 37894182 PMCID: PMC10609113 DOI: 10.3390/microorganisms11102524] [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: 08/29/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/29/2023] Open
Abstract
A sero-epidemiology study was conducted in Dhaka, Bangladesh between January 2020 and February 2021 to assess the immune responses to ETEC infection in adults and children. (1) Background: Enterotoxigenic Escherichia coli infection is a main cause of diarrheal disease in endemic countries. The characterization of the immune responses evoked by natural infection can guide vaccine development efforts. (2) Methods: A total of 617 adult and 480 pediatric diarrheal patients were screened, and 43 adults and 46 children (below 5 years of age) with an acute ETEC infection completed the study. The plasma samples were analyzed for antibody responses against the ETEC toxins. (3) Results: Heat-stable toxin (ST)-positive ETEC is the main cause of ETEC infection in adults, unlike in children in an endemic setting. We detected very low levels of anti-ST antibodies, and no ST-neutralizing activity. However, infection with ETEC strains expressing the heat-labile toxin (LT) induced systemic antibody responses in less than 25% of subjects. The antibody levels against LTA and LTB, as well as cholera toxin (CT), correlated well. The anti-LT antibodies were shown to have LT- and CT- neutralizing activity. The antibody reactivity against linear LT epitopes did not correlate with toxin-neutralizing activity. (4) Conclusions: Unlike LT, ST is a poor antigen and even adults have low anti-ST antibody levels that do not allow for the detection of toxin-neutralizing activity.
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Affiliation(s)
- Petra Girardi
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (T.H.); (E.N.)
| | - Taufiqur Rahman Bhuiyan
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research Bangladesh (ICDDR,B), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh; (T.R.B.); (F.K.); (F.Q.)
| | - Samuel B. Lundin
- Department of Microbiology and Immunology, University of Gothenburg, 405 30 Goteborg, Sweden; (S.B.L.); (A.M.H.)
| | - Shushan Harutyunyan
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (T.H.); (E.N.)
| | - Irene Neuhauser
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (T.H.); (E.N.)
| | - Farhana Khanam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research Bangladesh (ICDDR,B), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh; (T.R.B.); (F.K.); (F.Q.)
| | - Gábor Nagy
- CEBINA GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (G.N.); (V.S.)
| | - Valéria Szijártó
- CEBINA GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (G.N.); (V.S.)
| | - Tamás Henics
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (T.H.); (E.N.)
| | - Eszter Nagy
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (T.H.); (E.N.)
| | - Ali M. Harandi
- Department of Microbiology and Immunology, University of Gothenburg, 405 30 Goteborg, Sweden; (S.B.L.); (A.M.H.)
- Vaccine Evaluation Center, BC Children’s Hospital Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Firdausi Qadri
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research Bangladesh (ICDDR,B), 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh; (T.R.B.); (F.K.); (F.Q.)
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6
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Maier N, Grahek SL, Halpern J, Restrepo S, Troncoso F, Shimko J, Torres O, Belkind-Gerson J, Sack DA, Svennerholm AM, Gustafsson B, Sjöstrand B, Carlin N, Bourgeois AL, Porter CK. Efficacy of an Enterotoxigenic Escherichia coli (ETEC) Vaccine on the Incidence and Severity of Traveler's Diarrhea (TD): Evaluation of Alternative Endpoints and a TD Severity Score. Microorganisms 2023; 11:2414. [PMID: 37894071 PMCID: PMC10609384 DOI: 10.3390/microorganisms11102414] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 09/15/2023] [Accepted: 09/20/2023] [Indexed: 10/29/2023] Open
Abstract
The efficacy of an Oral Whole Cell ETEC Vaccine (OEV) against Travelers' Diarrhea (TD) was reexamined using novel outcome and immunologic measures. More specifically, a recently developed disease severity score and alternative clinical endpoints were evaluated as part of an initial validation effort to access the efficacy of a vaccine intervention for the first time in travelers to an ETEC endemic area. A randomized, double-blind, placebo-controlled trial followed travelers to Guatemala or Mexico up to 28 days after arrival in the country following vaccination (two doses two weeks apart) with an ETEC vaccine. Fecal samples were collected upon arrival, departure, and during TD for pathogen identification. Serum was collected in a subset of subjects to determine IgA cholera toxin B subunit (CTB) antibody titers upon their arrival in the country. The ETEC vaccine's efficacy, utilizing a TD severity score and other alternative endpoints, including the relationship between antibody levels and TD risk, was assessed and compared to the per-protocol primary efficacy endpoint. A total of 1435 subjects completed 7-28 days of follow-up and had available data. Vaccine efficacy was higher against more severe (≥5 unformed stools/24 h) ETEC-attributable TD and when accounting for immunologic take (PE ≥ 50%; p < 0.05). The vaccine protected against less severe (3 and 4 unformed stools/24 h) ETEC-attributable TD when accounting for symptom severity or change in activity (PE = 76.3%, p = 0.01). Immunologic take of the vaccine was associated with a reduced risk of infection with ETEC and other enteric pathogens, and with lower TD severity. Clear efficacy was observed among vaccinees with a TD score of ≥4 or ≥5, regardless of immunologic take (PE = 72.0% and 79.0%, respectively, p ≤ 0.03). The vaccine reduced the incidence and severity of ETEC, and this warrants accelerated evaluation of the improved formulation (designated ETVAX), currently undergoing advanced field testing. Subjects with serum IgA titers to CTB had a lower risk of infection with ETEC and Campylobacter jejuni/coli. Furthermore, the TD severity score provided a more robust descriptor of disease severity and should be included as an endpoint in future studies.
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Affiliation(s)
| | - Shannon L. Grahek
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Jane Halpern
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Suzanne Restrepo
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Felipe Troncoso
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Janet Shimko
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Olga Torres
- Laboratorio Diagnostico Molecular, Guatemala City 01009, Guatemala;
| | | | - David A. Sack
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (S.L.G.); (J.H.); (S.R.); (F.T.); (J.S.); (D.A.S.)
| | - Ann-Mari Svennerholm
- Department of Microbiology and Immunology, University of Gothenburg, 405 30 Gothenburg, Sweden;
| | - Björn Gustafsson
- Scandinavian Biopharma Holding AB, 171 48 Stockholm, Sweden (B.S.); (N.C.)
| | - Björn Sjöstrand
- Scandinavian Biopharma Holding AB, 171 48 Stockholm, Sweden (B.S.); (N.C.)
| | - Nils Carlin
- Scandinavian Biopharma Holding AB, 171 48 Stockholm, Sweden (B.S.); (N.C.)
| | | | - Chad K. Porter
- Naval Medical Research Command, Silver Spring, MD 20910, USA;
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Kuhlmann FM, Grigura V, Vickers TJ, Prouty MG, Iannotti LL, Dulience SJL, Fleckenstein JM. Seroprevalence Study of Conserved Enterotoxigenic Escherichia coli Antigens in Globally Diverse Populations. Microorganisms 2023; 11:2221. [PMID: 37764065 PMCID: PMC10536235 DOI: 10.3390/microorganisms11092221] [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: 07/18/2023] [Revised: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 09/29/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) are common causes of infectious diarrhea among young children of low-and middle-income countries (LMICs) and travelers to these regions. Despite their significant contributions to the morbidity and mortality associated with childhood and traveler's diarrhea, no licensed vaccines are available. Current vaccine strategies may benefit from the inclusion of additional conserved antigens, which may contribute to broader coverage and enhanced efficacy, given their key roles in facilitating intestinal colonization and effective enterotoxin delivery. EatA and EtpA are widely conserved in diverse populations of ETEC, but their immunogenicity has only been studied in controlled human infection models and a population of children in Bangladesh. Here, we compared serologic responses to EatA, EtpA and heat-labile toxin in populations from endemic regions including Haitian children and subjects residing in Egypt, Cameroon, and Peru to US children and adults where ETEC infections are sporadic. We observed elevated IgG and IgA responses in individuals from endemic regions to each of the antigens studied. In a cohort of Haitian children, we observed increased immune responses following exposure to each of the profiled antigens. These findings reflect the wide distribution of ETEC infections across multiple endemic regions and support further evaluation of EatA and EtpA as candidate ETEC vaccine antigens.
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Affiliation(s)
- Frederick Matthew Kuhlmann
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine in Saint Louis, Saint Louis, MO 63110, USA; (F.M.K.); (V.G.); (T.J.V.)
| | - Vadim Grigura
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine in Saint Louis, Saint Louis, MO 63110, USA; (F.M.K.); (V.G.); (T.J.V.)
| | - Timothy J. Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine in Saint Louis, Saint Louis, MO 63110, USA; (F.M.K.); (V.G.); (T.J.V.)
| | | | - Lora L. Iannotti
- Institute for Public Health, Brown School, Washington University in Saint Louis, Saint Louis, MO 63110, USA; (L.L.I.); (S.J.L.D.)
| | - Sherlie Jean Louis Dulience
- Institute for Public Health, Brown School, Washington University in Saint Louis, Saint Louis, MO 63110, USA; (L.L.I.); (S.J.L.D.)
| | - James M. Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine in Saint Louis, Saint Louis, MO 63110, USA; (F.M.K.); (V.G.); (T.J.V.)
- Medicine Service, Infectious Diseases, Saint Louis VA Health Care System, St. Louis, MO 63110, USA
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8
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Berzosa M, Delgado-López A, Irache JM, Gamazo C. Optimization of Enterotoxigenic Escherichia coli (ETEC) Outer Membrane Vesicles Production and Isolation Method for Vaccination Purposes. Microorganisms 2023; 11:2088. [PMID: 37630648 PMCID: PMC10458947 DOI: 10.3390/microorganisms11082088] [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: 07/19/2023] [Revised: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 08/27/2023] Open
Abstract
The study addresses Enterotoxigenic Escherichia coli (ETEC), a significant concern in low-income countries. Despite its prevalence, there is no licensed vaccine against ETEC. Bacterial vesicle-based vaccines are promising due to their safety and diverse virulence factors. However, cost-effective production requires enhancing vesicle yield while considering altered properties due to isolation methods. The proposed method involves heat treatment and ultrafiltration to recover vesicles from bacterial cultures. Two vesicle types, collected from heat-treated (HT-OMV) or untreated (NT-OMV) cultures, were compared. Vesicles were isolated via ultrafiltration alone ("complete") or with ultracentrifugation ("sediment"). Preliminary findings suggest complete HT-OMV vesicles are suitable for an ETEC vaccine. They express important proteins (OmpA, OmpX, OmpW) and virulence factors (adhesin TibA). Sized optimally (50-200 nm) for mucosal vaccination, they activate macrophages, inducing marker expression (CD40, MHCII, CD80, CD86) and Th1/Th2 cytokine release (IL-6, MCP-1, TNF-α, IL12p70, IL-10). This study confirms non-toxicity in RAW 264.7 cells and the in vivo ability of complete HT-OMV to generate significant IgG2a/IgG1 serum antibodies. Results suggest promise for a cost-effective ETEC vaccine, requiring further research on in vivo toxicity, pathogen-specific antibody detection, and protective efficacy.
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Affiliation(s)
- Melibea Berzosa
- Department of Microbiology and Parasitology, Navarra Medical Research Institute (IdiSNA), University of Navarra, 31008 Pamplona, Spain
| | - Alberto Delgado-López
- Department of Microbiology and Parasitology, Navarra Medical Research Institute (IdiSNA), University of Navarra, 31008 Pamplona, Spain
| | - Juan Manuel Irache
- Department of Pharmacy and Pharmaceutical Technology, University of Navarra, 31008 Pamplona, Spain
| | - Carlos Gamazo
- Department of Microbiology and Parasitology, Navarra Medical Research Institute (IdiSNA), University of Navarra, 31008 Pamplona, Spain
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Westcott MM, Blevins M, Wierzba TF, Morse AE, White KR, Sanders LA, Sanders JW. The Immunogenicity and Properties of a Whole-Cell ETEC Vaccine Inactivated with Psoralen and UVA Light in Comparison to Formalin. Microorganisms 2023; 11:2040. [PMID: 37630600 PMCID: PMC10458022 DOI: 10.3390/microorganisms11082040] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/26/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
Inactivated whole-cell vaccines present a full repertoire of antigens to the immune system. Formalin treatment, a standard method for microbial inactivation, can modify or destroy protein antigenic epitopes. We tested the hypothesis that photochemical inactivation with psoralen and UVA light (PUVA), which targets nucleic acid, would improve the immunogenicity of an Enterotoxigenic E. coli (ETEC) vaccine relative to a formalin-inactivated counterpart. Exposure of ETEC H10407 to PUVA using the psoralen drug 4'-Aminomethyltrioxsalen hydrochloride (AMT) yielded replication-incompetent bacteria that retained their metabolic activity. CFA/I-mediated mannose-resistant hemagglutination (MRHA) was equivalent for PUVA-inactivated and live ETEC, but was severely reduced for formalin-ETEC, indicating that PUVA preserved fimbrial protein functional integrity. The immunogenicity of PUVA-ETEC and formalin-ETEC was compared in mice ± double mutant heat-labile enterotoxin (dmLT) adjuvant. Two weeks after an intramuscular prime/boost, serum anti-ETEC IgG titers were similar for the two vaccines and were increased by dmLT. However, the IgG responses raised against several conserved ETEC proteins were greater after vaccination with PUVA-ETEC. In addition, PUVA-ETEC generated IgG specific for heat-labile toxin (LT) in the absence of dmLT, which was not a property of formalin-ETEC. These data are consistent with PUVA preserving ETEC protein antigens in their native-like form and justify the further testing of PUVA as a vaccine platform for ETEC using murine challenge models.
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Affiliation(s)
- Marlena M. Westcott
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, 575 Patterson Ave, Winston Salem, NC 27101, USA; (A.E.M.); (K.R.W.)
| | - Maria Blevins
- Infectious Diseases Section, Wake Forest University School of Medicine, Medical Center Blvd, Winston Salem, NC 27157, USA; (M.B.); (T.F.W.); (L.A.S.); (J.W.S.)
| | - Thomas F. Wierzba
- Infectious Diseases Section, Wake Forest University School of Medicine, Medical Center Blvd, Winston Salem, NC 27157, USA; (M.B.); (T.F.W.); (L.A.S.); (J.W.S.)
| | - Alexis E. Morse
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, 575 Patterson Ave, Winston Salem, NC 27101, USA; (A.E.M.); (K.R.W.)
| | - Kinnede R. White
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, 575 Patterson Ave, Winston Salem, NC 27101, USA; (A.E.M.); (K.R.W.)
| | - Leigh Ann Sanders
- Infectious Diseases Section, Wake Forest University School of Medicine, Medical Center Blvd, Winston Salem, NC 27157, USA; (M.B.); (T.F.W.); (L.A.S.); (J.W.S.)
| | - John W. Sanders
- Infectious Diseases Section, Wake Forest University School of Medicine, Medical Center Blvd, Winston Salem, NC 27157, USA; (M.B.); (T.F.W.); (L.A.S.); (J.W.S.)
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10
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Park JY, Cho SH. Production of monoclonal antibody of heat-labile toxin A subunit to identify enterotoxigenic Escherichia coli by epitope mapping using synthetic peptides. Front Immunol 2023; 14:1152910. [PMID: 37275900 PMCID: PMC10232981 DOI: 10.3389/fimmu.2023.1152910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 05/05/2023] [Indexed: 06/07/2023] Open
Abstract
Background Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea through two enterotoxins, a heat-labile toxin and a heat-stable toxin. These toxins alter the cellular signaling pathways, ultimately triggering an increase in chloride secretion and watery diarrhea. Objective For the development of an ETEC vaccine, we attempted to construct a peptide-specific monoclonal antibody library against heat-labile enterotoxin A subunit (LT-A) by epitope mapping using synthetic peptides. Methods Sera produced by five mice immunized with recombinant LT-A protein were examined for specific recognition with synthetic 15-mer and 34-mer peptides of LT-A proteins using enzyme-linked immunosorbent assay. The analysis revealed that the synthetic peptides number 8, 16, 24, 33, 36, 38, and 39 reacted with an anti-LT-A polyclonal antibody. For the possible prediction of LT-A epitopes, each full-length protein sequence was subjected to BCPreds analysis and three-dimensional protein structure analysis. The data showed that three peptides (synthetic peptide numbers: 33, 36, and 38-39) have identical antigenic specificities with LT-A protein, suggesting the usefulness of these linear peptide epitopes. Results Based on these peptides, we produced monoclonal antibodies to improve the specificity of LT-A detection. Monoclonal antibodies produced from two peptides (numbers 33 and 36) showed affinity for an LT-A recombinant antigen. Moreover, peptide epitope prediction analysis showed that the sites of the three peptides were identical to those exhibiting actual antigenicity. Also, it was confirmed that the amino acid sequence that actually showed antigenicity was included in the peptide predicted only by ETEC-LT-A-33. Also, the specificity of the antibody for ETEC-LT-A-33 was validated using bacterial cells, and the neutralizing effect of the antibody was determined by assessing cytokine release in infected HCT-8 cells. Conclusion The monoclonal antibodies produced in this study are useful toolsfor vaccine production against ETEC and can be used to identify peptide antigencandidates.
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Affiliation(s)
- Jun-Young Park
- Division of Zoonotic and Vector Borne Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Republic of Korea
- Environmental Diseases Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Seung-Hak Cho
- Division of Zoonotic and Vector Borne Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Republic of Korea
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11
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Stone AE, Rambaran S, Trinh IV, Estrada M, Jarand CW, Williams BS, Murrell AE, Huerter CM, Bai W, Palani S, Nakanishi Y, Laird RM, Poly FM, Reed WF, White JA, Norton EB. Route and antigen shape immunity to dmLT-adjuvanted vaccines to a greater extent than biochemical stress or formulation excipients. Vaccine 2023; 41:1589-1601. [PMID: 36732163 PMCID: PMC10308557 DOI: 10.1016/j.vaccine.2023.01.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 01/06/2023] [Accepted: 01/16/2023] [Indexed: 02/04/2023]
Abstract
A key aspect to vaccine efficacy is formulation stability. Biochemical evaluations provide information on optimal compositions or thermal stability but are routinely validated by ex vivo analysis and not efficacy in animal models. Here we assessed formulations identified to improve or reduce stability of the mucosal adjuvant dmLT being investigated in polio and enterotoxigenic E. coli (ETEC) clinical vaccines. We observed biochemical changes to dmLT protein with formulation or thermal stress, including aggregation or subunit dissociation or alternatively resistance against these changes with specific buffer compositions. However, upon injection or mucosal vaccination with ETEC fimbriae adhesin proteins or inactivated polio virus, experimental findings indicated immunization route and co-administered antigen impacted vaccine immunogenicity more so than dmLT formulation stability (or instability). These results indicate the importance of both biochemical and vaccine-derived immunity assessment in formulation optimization. In addition, these studies have implications for use of dmLT in clinical settings and for delivery in resource poor settings.
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Affiliation(s)
- Addison E Stone
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Saraswatie Rambaran
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Ivy V Trinh
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | | | - Curtis W Jarand
- Department of Physics and Engineering Physics, Tulane University School of Medicine, New Orleans, LA, USA
| | - Blake S Williams
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Amelie E Murrell
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Chelsea M Huerter
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - William Bai
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Surya Palani
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | | | - Renee M Laird
- Henry M. Jackson Foundation for Military Medicine, Bethesda, MD, USA; Enteric Diseases Department, Naval Medical Research Center, Silver Spring, Maryland, USA
| | - Frederic M Poly
- Enteric Diseases Department, Naval Medical Research Center, Silver Spring, Maryland, USA
| | - Wayne F Reed
- Department of Physics and Engineering Physics, Tulane University School of Medicine, New Orleans, LA, USA
| | | | - Elizabeth B Norton
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, LA, USA.
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12
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Detection of Escherichia coli in Food Samples by Magnetosome-based Biosensor. BIOTECHNOL BIOPROC E 2023. [DOI: 10.1007/s12257-022-0235-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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13
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Williams AJ, Warfel KF, Desai P, Li J, Lee JJ, Wong DA, Nguyen PM, Qin Y, Sobol SE, Jewett MC, Chang YF, DeLisa MP. A low-cost recombinant glycoconjugate vaccine confers immunogenicity and protection against enterotoxigenic Escherichia coli infections in mice. Front Mol Biosci 2023; 10:1085887. [PMID: 36936989 PMCID: PMC10018396 DOI: 10.3389/fmolb.2023.1085887] [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: 10/31/2022] [Accepted: 02/14/2023] [Indexed: 03/06/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is the primary etiologic agent of traveler's diarrhea and a major cause of diarrheal disease and death worldwide, especially in infants and young children. Despite significant efforts over the past several decades, an affordable vaccine that appreciably decreases mortality and morbidity associated with ETEC infection among children under the age of 5 years remains an unmet aspirational goal. Here, we describe robust, cost-effective biosynthetic routes that leverage glycoengineered strains of non-pathogenic E. coli or their cell-free extracts for producing conjugate vaccine candidates against two of the most prevalent O serogroups of ETEC, O148 and O78. Specifically, we demonstrate site-specific installation of O-antigen polysaccharides (O-PS) corresponding to these serogroups onto licensed carrier proteins using the oligosaccharyltransferase PglB from Campylobacter jejuni. The resulting conjugates stimulate strong O-PS-specific humoral responses in mice and elicit IgG antibodies that possess bactericidal activity against the cognate pathogens. We also show that one of the prototype conjugates decorated with serogroup O148 O-PS reduces ETEC colonization in mice, providing evidence of vaccine-induced mucosal protection. We anticipate that our bacterial cell-based and cell-free platforms will enable creation of multivalent formulations with the potential for broad ETEC serogroup protection and increased access through low-cost biomanufacturing.
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Affiliation(s)
- Asher J. Williams
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Katherine F. Warfel
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute, Evanston, IL, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, United States
- Center for Synthetic Biology, Northwestern University, Technological Institute, Evanston, IL, United States
| | - Primit Desai
- Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, United States
| | - Jie Li
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Jen-Jie Lee
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Derek A. Wong
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute, Evanston, IL, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, United States
- Center for Synthetic Biology, Northwestern University, Technological Institute, Evanston, IL, United States
| | - Phuong M. Nguyen
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Yufan Qin
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Sarah E. Sobol
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute, Evanston, IL, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, United States
- Center for Synthetic Biology, Northwestern University, Technological Institute, Evanston, IL, United States
| | - Michael C. Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute, Evanston, IL, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, United States
- Center for Synthetic Biology, Northwestern University, Technological Institute, Evanston, IL, United States
- Department of Bioengineering, Stanford University, Stanford, CA, United States
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Matthew P. DeLisa
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
- Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, United States
- Cornell Institute of Biotechnology, Cornell University, Ithaca, NY, United States
- *Correspondence: Matthew P. DeLisa,
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14
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Walker RI, Bourgeois AL. Oral inactivated whole cell vaccine for mucosal immunization: ETVAX case study. Front Immunol 2023; 14:1125102. [PMID: 36936951 PMCID: PMC10018008 DOI: 10.3389/fimmu.2023.1125102] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/03/2023] [Indexed: 03/06/2023] Open
Abstract
Oral immunization is an effective strategy for inducing protective immunity against mucosal enteric pathogens. Although live-attenuated as well as subunit approaches have been explored for vaccination against enteric pathogens, inactivated whole bacterial cells may also be effective in introducing protective immunity. Successfully accomplishing this goal with inactivated whole bacterial cells will require that a complex antigenic repertoire be presented in controlled immunogenic amounts, in a safe and relatively simple and self-contained delivery format. The benefit from immunization with whole cell vaccines can be further enhanced through genetic engineering to over-express selected antigens and also by the use of mucosal adjuvants to direct a more robust immunologic response. These steps are being taken for the development of ETVAX, the most clinically advanced vaccine candidate against the major enteric pathogen, enterotoxigenic Escherichia coli (ETEC) with significant positive impact.
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15
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Choy RKM, Bourgeois AL, Ockenhouse CF, Walker RI, Sheets RL, Flores J. Controlled Human Infection Models To Accelerate Vaccine Development. Clin Microbiol Rev 2022; 35:e0000821. [PMID: 35862754 PMCID: PMC9491212 DOI: 10.1128/cmr.00008-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The timelines for developing vaccines against infectious diseases are lengthy, and often vaccines that reach the stage of large phase 3 field trials fail to provide the desired level of protective efficacy. The application of controlled human challenge models of infection and disease at the appropriate stages of development could accelerate development of candidate vaccines and, in fact, has done so successfully in some limited cases. Human challenge models could potentially be used to gather critical information on pathogenesis, inform strain selection for vaccines, explore cross-protective immunity, identify immune correlates of protection and mechanisms of protection induced by infection or evoked by candidate vaccines, guide decisions on appropriate trial endpoints, and evaluate vaccine efficacy. We prepared this report to motivate fellow scientists to exploit the potential capacity of controlled human challenge experiments to advance vaccine development. In this review, we considered available challenge models for 17 infectious diseases in the context of the public health importance of each disease, the diversity and pathogenesis of the causative organisms, the vaccine candidates under development, and each model's capacity to evaluate them and identify correlates of protective immunity. Our broad assessment indicated that human challenge models have not yet reached their full potential to support the development of vaccines against infectious diseases. On the basis of our review, however, we believe that describing an ideal challenge model is possible, as is further developing existing and future challenge models.
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Affiliation(s)
- Robert K. M. Choy
- PATH, Center for Vaccine Innovation and Access, Seattle, Washington, USA
| | - A. Louis Bourgeois
- PATH, Center for Vaccine Innovation and Access, Seattle, Washington, USA
| | | | - Richard I. Walker
- PATH, Center for Vaccine Innovation and Access, Seattle, Washington, USA
| | | | - Jorge Flores
- PATH, Center for Vaccine Innovation and Access, Seattle, Washington, USA
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16
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Upadhyay I, Lauder KL, Li S, Ptacek G, Zhang W. Intramuscularly Administered Enterotoxigenic Escherichia coli (ETEC) Vaccine Candidate MecVax Prevented H10407 Intestinal Colonization in an Adult Rabbit Colonization Model. Microbiol Spectr 2022; 10:e0147322. [PMID: 35762781 PMCID: PMC9431210 DOI: 10.1128/spectrum.01473-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/14/2022] [Indexed: 11/20/2022] Open
Abstract
Currently, there are no vaccines licensed for enterotoxigenic Escherichia coli (ETEC), a leading cause of children's diarrhea in developing countries and the most common cause of travelers' diarrhea. A vaccine preventing ETEC bacteria from colonization at small intestines and neutralizing enterotoxin toxicity is expected to be effective against ETEC diarrhea. Protein-based multivalent vaccine candidate MecVax was demonstrated recently to induce antibodies neutralizing heat-labile toxin (LT) and heat-stable toxin (STa) enterotoxicity and inhibiting adherence of seven ETEC adhesins (CFA/I, CS1 to CS6) but also to protect against ETEC toxin-mediated clinical diarrhea in a pig challenge model. To further evaluate MecVax preclinical efficacy against ETEC colonization at small intestines, in this study, we intramuscularly immunized adult rabbits with MecVax, challenged rabbits with ETEC strain H10407 (CFA/I, LT, STa), and examined prevention of bacteria intestinal colonization. Data showed that rabbits immunized with MecVax developed antibodies to both ETEC toxins (LT, STa) and seven adhesins (CFA/I, CS1 to CS6) and had over 99.9% reduction of H10407 intestinal colonization, indicating that the broadly immunogenic ETEC vaccine candidate MecVax is protective against ETEC H10407 intestinal colonization. This study also confirmed that parenteral administration of a protein-based vaccine can prevent bacteria intestinal colonization. Protection against ETEC intestinal colonization demonstrated by this rabbit study, in conjugation with protection against ETEC enterotoxin-mediated clinical diarrhea from a previous pig challenge study, suggested that MecVax can potentially be an effective ETEC vaccine and a combined pig and rabbit challenge model can evaluate ETEC vaccine preclinical efficacy. IMPORTANCE An effective ETEC vaccine would prevent hundreds of millions of diarrhea clinical cases and save nearly 100,000 lives annually. MecVax, a protein-based injectable multivalent ETEC vaccine candidate, has been shown for the first time to induce functional antibodies against both ETEC enterotoxins (STa, LT) produced by all ETEC strains and seven ETEC adhesins (CFA/I, CS1 to CS6) expressed by ETEC strains causing a majority of ETEC diarrhea clinical cases and the moderate-to-severe cases. Moreover, MecVax was demonstrated to protect against ETEC STa or LT toxin-mediated diarrhea in a pig model. If it also protects against ETEC intestinal colonization, MecVax can be validated as an effective ETEC vaccine candidate. This adult rabbit colonization model study showed that intramuscular administration of MecVax effectively prevented intestinal colonization by H10407, perhaps the most virulent ETEC strain, affirming MecVax vaccine candidacy and accelerating vaccine development against ETEC children's diarrhea and travelers' diarrhea.
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Affiliation(s)
- Ipshita Upadhyay
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
| | - Kathryn L. Lauder
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
| | - Siqi Li
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
| | - Galen Ptacek
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
| | - Weiping Zhang
- University of Illinois at Urbana-Champaign, Department of Pathobiology, Urbana, Illinois, USA
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17
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Hassanzadeh P, Atyabi F, Dinarvand R. Nanobionics: From plant empowering to the infectious disease treatment. J Control Release 2022; 349:890-901. [PMID: 35901860 DOI: 10.1016/j.jconrel.2022.07.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 10/16/2022]
Abstract
Infectious diseases (ID) are serious threats against the global health and socio-economic conditions. Vaccination usually plays a key role in disease prevention, however, insufficient efficiency or immunogenicity may be quite challenging. Using the advanced vectors for delivery of vaccines with suitable efficiency, safety, and immune-modulatory activity, and tunable characteristics could be helpful, but there are no systematic reviews confirming the capabilities of the vaccine delivery systems for covering various types of pathogens. Furthermore, high rates of the infections, transmission, and fatal ratio and diversity of the pathogens and infection mechanisms may negatively influence vaccine effectiveness. The absence of highly-effective antibiotics against the resistant strains of bacteria and longevity of antibiotic testing have provoked increasing needs towards the application of more accurate and specific theranostic strategies including the nanotechnology-based ones. Nanobionics which is based on the charge storage and transport in the molecular structures, could be of key value in the molecular diagnostic tests and highly-specific electro-analytical methods or devices. Such devices based on the early disease diagnostics might be of critical significance against various types of diseases. This article highlights the significance of nanobionics against ID.
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Affiliation(s)
- Parichehr Hassanzadeh
- Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 13169-43551, Iran; Sasan Hospital, Tehran 14159-83391, Iran.
| | - Fatemeh Atyabi
- Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 13169-43551, Iran
| | - Rassoul Dinarvand
- Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 13169-43551, Iran
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18
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Asmani F, Khavari-Nejad RA, Salmanian AH, Amani J. Immunological evaluation of recombinant chimeric construct from Enterotoxigenic E. coli expressed in hairy roots. Mol Immunol 2022; 147:81-89. [DOI: 10.1016/j.molimm.2022.02.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 01/26/2022] [Accepted: 02/09/2022] [Indexed: 01/05/2023]
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19
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Zhang Y, Tan P, Zhao Y, Ma X. Enterotoxigenic Escherichia coli: intestinal pathogenesis mechanisms and colonization resistance by gut microbiota. Gut Microbes 2022; 14:2055943. [PMID: 35358002 PMCID: PMC8973357 DOI: 10.1080/19490976.2022.2055943] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea in children and travelers in developing countries. ETEC is characterized by the ability to produce major virulence factors including colonization factors (CFs) and enterotoxins, that bind to specific receptors on epithelial cells and induce diarrhea. The gut microbiota is a stable and sophisticated ecosystem that performs a range of beneficial functions for the host, including protection against pathogen colonization. Understanding the pathogenic mechanisms of ETEC and the interaction between the gut microbiota and ETEC represents not only a research need but also an opportunity and challenge to develop precautions for ETEC infection. Herein, this review focuses on recent discoveries about ETEC etiology, pathogenesis and clinical manifestation, and discusses the colonization resistances mediated by gut microbiota, as well as preventative strategies against ETEC with an aim to provide novel insights that can reduce the adverse effect on human health.
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Affiliation(s)
- Yucheng Zhang
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Peng Tan
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Ying Zhao
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Xi Ma
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China,CONTACT Xi Ma State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
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20
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Soltan MA, Behairy MY, Abdelkader MS, Albogami S, Fayad E, Eid RA, Darwish KM, Elhady SS, Lotfy AM, Alaa Eldeen M. In silico Designing of an Epitope-Based Vaccine Against Common E. coli Pathotypes. Front Med (Lausanne) 2022; 9:829467. [PMID: 35308494 PMCID: PMC8931290 DOI: 10.3389/fmed.2022.829467] [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: 12/05/2021] [Accepted: 01/21/2022] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli (E. coli) is a Gram-negative bacterium that belongs to the family Enterobacteriaceae. While E. coli can stay as an innocuous resident in the digestive tract, it can cause a group of symptoms ranging from diarrhea to live threatening complications. Due to the increased rate of antibiotic resistance worldwide, the development of an effective vaccine against E. coli pathotypes is a major health priority. In this study, a reverse vaccinology approach along with immunoinformatics has been applied for the detection of potential antigens to develop an effective vaccine. Based on our screening of 5,155 proteins, we identified lipopolysaccharide assembly protein (LptD) and outer membrane protein assembly factor (BamA) as vaccine candidates for the current study. The conservancy of these proteins in the main E. coli pathotypes was assessed through BLASTp to make sure that the designed vaccine will be protective against major E. coli pathotypes. The multitope vaccine was constructed using cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and B cell lymphocyte (BCL) epitopes with suitable linkers and adjuvant. Following that, it was analyzed computationally where it was found to be antigenic, soluble, stable, and non-allergen. Additionally, the adopted docking study, as well as all-atom molecular dynamics simulation, illustrated the promising predicted affinity and free binding energy of this constructed vaccine against the human Toll-like receptor-4 (hTLR-4) dimeric state. In this regard, wet lab studies are required to prove the efficacy of the potential vaccine construct that demonstrated promising results through computational validation.
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Affiliation(s)
- Mohamed A. Soltan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Sinai University, Ismailia, Egypt
| | - Mohammed Y. Behairy
- Department of Microbiology and Immunology, Faculty of Pharmacy, University of Sadat City, Sadat City, Egypt
| | - Mennatallah S. Abdelkader
- Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
| | - Sarah Albogami
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Eman Fayad
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Refaat A. Eid
- Department of Pathology, College of Medicine, King Khalid University, Abha, Saudi Arabia
| | - Khaled M. Darwish
- Department of Medicinal Chemistry, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
| | - Sameh S. Elhady
- Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ahmed M. Lotfy
- Department of Pharmacology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Muhammad Alaa Eldeen
- Division of Cell Biology, Histology and Genetics, Department of Zoology, Faculty of Science, Zagazig University, Zagazig, Egypt
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21
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Connor S, Velagic M, Zhang X, Johura FT, Chowdhury G, Mukhopadhyay AK, Dutta S, Alam M, Sack DA, Wierzba TF, Chakraborty S. Evaluation of a simple, rapid and field-adapted diagnostic assay for enterotoxigenic E. coli and Shigella. PLoS Negl Trop Dis 2022; 16:e0010192. [PMID: 35130310 PMCID: PMC8853640 DOI: 10.1371/journal.pntd.0010192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 02/17/2022] [Accepted: 01/21/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding the global burden of enterotoxigenic E. coli (ETEC) and Shigella diarrhea as well as estimating the cost effectiveness of vaccines to control these two significant pathogens have been hindered by the lack of a diagnostic test that is rapid, simple, sensitive, and can be applied to the endemic countries. We previously developed a simple and rapid assay, Rapid Loop mediated isothermal amplification based Diagnostic Test (RLDT) for the detection of ETEC and Shigella spp. (Shigella). In this study, the RLDT assay was evaluated in comparison with quantitative PCR (qPCR), culture and conventional PCR for the detection of ETEC and Shigella. This validation was performed using previously collected stool samples from endemic countries, from the travelers to the endemic countries, as well as samples from a controlled human infection model study of ETEC. The performance of RLDT from dried stool spots was also validated. RLDT resulted in excellent sensitivity and specificity compared to qPCR (99% and 99.2% respectively) ranging from 92.3 to 100% for the individual toxin genes of ETEC and 100% for Shigella. Culture was less sensitive compared to RLDT. No significant differences were noted in the performance of RLDT using samples from various sources or stool samples from moderate to severe diarrhea or asymptomatic infections. RLDT performed equally well in detection of ETEC and Shigella from the dried stool samples on filter papers. This study established that RLDT is sufficiently sensitive and specific to be used as a simple and rapid diagnostic assay to detect ETEC and Shigella in endemic countries to determine disease burden of these pathogens in the national and subnational levels. This information will be important to guide public health and policy makers to prioritize resources for accelerating the development and introduction of effective preventative and/or treatment interventions against these enteric infections. Enterotoxigenic E. coli (ETEC) and Shigella spp (Shigella) causes significant global morbidity and mortality, especially in low-and middle-income countries (LMICs). Since culture methods to detect Shigella are not sensitive, and the methods used to detect ETEC have not been feasible outside of specialized, well-equipped laboratories, the true burden of these pathogens at national and sub-national levels are mostly not available. Morbidity and mortality estimates, for these two pathogens are crucial to assess their relative public health importance in LMICs. We developed a simple and rapid diagnostic assay called the RLDT (Rapid Loop-mediated isothermal amplification based Diagnostic Test) for detection of ETEC and Shigella. In this study we evaluated RLDT compared to other currently available assays using previously collected stool samples. Our data showed that the RLDT assay exhibited high sensitivity and specificity for detection of ETEC and Shigella, with its result available within 50 minutes. The sensitivity of RLDT was higher than culture for these pathogens. We conclude that RLDT could be used as a rapid and simple diagnostic test to determine the burden of ETEC and Shigella in LMICs as well as in clinical vaccine trials of these pathogens.
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Affiliation(s)
- Sean Connor
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Mirza Velagic
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Xueyan Zhang
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Fatema-Tuz Johura
- icddr,b, Formerly International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Goutam Chowdhury
- ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | | | - Shanta Dutta
- ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Munirul Alam
- icddr,b, Formerly International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - David A. Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Thomas F. Wierzba
- Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
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22
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Debes AK, Xiao S, Liu J, Shaffer A, Scalzo P, Guenou E, Beyala L, Pascal GA, Chebe AN, Tchio-Nighie H, Sonia NS, Ram M, Sack DA, Ateudjieu J. Characterization of Enteric Disease in Children by Use of a Low-Cost Specimen Preservation Method. J Clin Microbiol 2021; 59:e0170321. [PMID: 34524885 PMCID: PMC8601215 DOI: 10.1128/jcm.01703-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/08/2021] [Indexed: 11/20/2022] Open
Abstract
Diarrhea is a leading cause of death in children under five. Molecular methods exist for the rapid detection of enteric pathogens; however, the logistical costs of storing stool specimens limit applicability. We sought to demonstrate that dried specimens preserved using filter paper can be used to identify diarrheal diseases causing significant morbidity among children in resource-constrained countries. A substudy was nested into cholera surveillance in Cameroon. Enrollment criteria included enrollment between 1 August 2016 and 1 October 2018, age of <18 years, availability of a stool specimen, and having three or more loose stools within 24 h with the presence of dehydration and/or blood. A total of 7,227 persons were enrolled, of whom 2,746 met enrollment criteria and 337 were included in this analysis using the enteric TaqMan array card. Bacterial pathogens were compared to severity of diarrhea, age, and sex, among other variables. One hundred seven were positive for enterotoxigenic Escherichia coli, of which 40.2% (n = 43) had heat-labile enterotoxin (LT) and the heat-stable enterotoxin STh, 19.6% (n = 21) had LT and the heat-stable enterotoxin STp, and 49.5% (n = 53) had LT only. Major colonization factors (CFs) were present in 43.9% of enterotoxigenic E. coli (ETEC)-positive patients. Ninety-six were positive for Shigella, of whom 14 (14.6%) reported dysentery. Model-derived quantitative cutoffs identified 116 (34.4%) with one highly diarrhea-associated pathogen and 16 (4.7%) with two or more. Shigella and rotavirus were most strongly associated with diarrhea in children with mixed infections. Dried-filter-paper-preserved specimens eliminate the need for frozen stool specimens and will facilitate enteric surveillance and contribute to the understanding of disease burden, which is needed to guide vaccine development and introduction. This study confirms rotavirus, Shigella, and ETEC as major contributors to pediatric diarrheal disease in two regions of Cameroon.
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Affiliation(s)
- Amanda K. Debes
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Shaoming Xiao
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Jie Liu
- University of Virginia, Charlottesville, Virginia, USA
| | - Allison Shaffer
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Paul Scalzo
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | - Landry Beyala
- Meilleur Accès aux Soins de Santé, Yaoundé, Cameroon
| | | | | | | | | | - Malathi Ram
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - David A. Sack
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Jerome Ateudjieu
- Meilleur Accès aux Soins de Santé, Yaoundé, Cameroon
- Department of Public Health, Faculty of Medicine and Pharmaceutical Sciences, University of Dschang, Dschang, Cameroon
- Clinical Research Unit, Division of Health Operations Research, Ministry of Public Health, Yaoundé, Cameroon
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Moon J, Barry EM. Sequence variations in the ETEC CS6 operon affect transcript and protein expression. Virulence 2021; 12:2659-2669. [PMID: 34672874 PMCID: PMC8923064 DOI: 10.1080/21505594.2021.1981000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrheal disease in developing nations where it accounts for a significant disease burden in children between the ages of 0 to 59 months. It is also the number one bacterial causative agent of traveler’s diarrhea. ETEC infects hosts through the fecal-oral route and utilizes colonization factors (CF) to adhere within the small intestine. Over 25 CFs have been identified; 7 are considered major CFs and a vaccine targeting these is predicted to provide protection against up to 66% of ETEC associated disease. Coli Surface Antigen 6 (CS6) is a major CF and is associated with disease-causing ETEC isolates. Analysis of the CS6 operon sequence led to the identification of two regions of variability among clinical isolates which we predicted exert effects on CS6 transcript and protein expression. A total of 7 recombinant E. coli strains were engineered to encode the CS6 operon in wild-type, hybrid, and mutant configurations. Western blot analysis and RT-qPCR provided evidence to support the importance of an intergenic hairpin structure on CS6 expression. Our results reveal the significance of CS6 sequence selection regarding ETEC vaccine development and present novel information regarding CS6 sequence variation in WT ETEC strains.
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Affiliation(s)
- Jonathan Moon
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Eileen M Barry
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, USA
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24
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Sarker MHR, Moriyama M, Rahman MM, Das SK, Uzzaman MN, Das J, Uddin A, Banu S, Khan SH, Shahid ASMSB, Shahunja KM, Chisti MJ, Faruque ASG, Ahmed T. Characteristics of Rotavirus, ETEC, and Vibrio Cholerae Among Under 2-year Children Attending an Urban Diarrheal Disease Hospital in Bangladesh. J Prim Care Community Health 2021; 12:21501327211049118. [PMID: 34632833 PMCID: PMC8512248 DOI: 10.1177/21501327211049118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Information on comparative clinical and host characteristics of under-2
children with watery diarrhea caused by rotavirus, Enterotoxigenic
Escherichia coli (ETEC), and Vibrio cholerae
as single pathogens is lacking. We sought to investigate the
sociodemographic, clinical, and host characteristics of under-2 children
hospitalized due to these pathogens. Methodology We conducted a hospital-based case-control study using the icddr,b Diarrheal
Diseases Surveillance System. Children of either sex, <2 years with
diarrhea, who attended the hospital during 2014 to 2018, constituted the
study population. Stool specimens having a single pathogen like rotavirus,
ETEC, or Vibrio cholerae constituted the cases and stool
specimens having no detectable common enteropathogens comprised the
controls. Multinomial logistic regression analysis was done where control
was the reference group. Results A total of 14 889 patients were enrolled, 6939 of whom were under-2 children,
and 5245 (76%) constituted our study population. Among them 48% (n = 2532),
3% (n = 148) and 1% (n = 49) had rotavirus, ETEC, and Vibrio
cholera, respectively. A control group (diarrhea without these
3 or Shigella, Salmonella,
Aeromonas) accounted for 48% (n = 2516). In multinomial
regression model, children with rotavirus (adjusted odds ratio [aOR], 1.36;
95% confidence interval [95% CI], 1.19-1.55) less often presented with
dehydrating diarrhea compared to those with ETEC (aOR, 1.54; 95% CI,
1.05-2.26) and cholera (aOR, 2.25; 95% CI, 1.11-4.57). Rotavirus diarrhea
was associated (aOR, 1.25; 95% CI, 1.07-1.46) with those who received
antimicrobials prior to hospital admission and protectively associated with
drinking tap water (aOR, 0.84; 95% CI, 0.73-0.95); however, ETEC diarrhea
had protective association (aOR, 0.62; 95% CI, 0.43-0.92) with children who
received antimicrobials prior to hospital admission and was associated with
drinking tap water (aOR, 1.78; 95% CI, 1.19-2.66). Use of intravenous fluid
was associated with cholera (aOR, 10.36; 95% CI, 4.85-22.16) and had
protective association with rotavirus episodes (aOR, 0.64; 95% CI,
0.45-0.91). Conclusions Clinical presentations and host characteristics of rotavirus, ETEC, and
Vibrio cholerae diarrhea differed from each other and
the information may be helpful for clinicians for better understanding and
proper management of these children.
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Affiliation(s)
- Mohammad Habibur Rahman Sarker
- Hiroshima University, Hiroshima,
Japan
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | | | | | | | - Md Nazim Uzzaman
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Jui Das
- The University of Queensland, Brisbane,
Australia
| | - Aftab Uddin
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Shakila Banu
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Soroar Hossain Khan
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Abu SMSB Shahid
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | | | - Mohammod Jobayer Chisti
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
- Mohammod Jobayer Chisti, Nutrition and
Clinical Services Division (NCSD), 68, Shaheed Tajuddin Ahmed Sarani Mohakhali,
Dhaka 1212, Bangladesh.
| | - Abu S. G. Faruque
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Tahmeed Ahmed
- International Centre for Diarrhoeal
Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
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25
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Percentage Destabilization Effect of Some West African Medicinal Plants on the Outer Membrane of Various Bacteria Involved in Infectious Diarrhea. BIOMED RESEARCH INTERNATIONAL 2021; 2021:4134713. [PMID: 34540993 PMCID: PMC8445716 DOI: 10.1155/2021/4134713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 08/12/2021] [Indexed: 12/02/2022]
Abstract
Previous work stated that Khaya senegalensis, Anacardium ouest L., Pterocarpus erinaceus, Diospyros mespiliformis, Ocimum gratissimum, Manihot esculenta, Vernonia amygdalina Delile, and Daniellia oliveri have a great potential for the fight against infectious diarrhea. However, data on their antibacterial activity on strains of bacteria responsible for infectious diarrhea are not available. This study is aimed at elucidating the mechanism of action of the antibacterial effect of these plants on some bacterial strains responsible for diarrheal infections. The design of the study included first evaluating the degree of sensitivity of Salmonella typhimurium 14028, Escherichia coli ATCC 25922, Shigella spp., and Salmonella spp. strains to aqueous and hydroethanolic extracts of each plant, followed by the determination of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibiotic power (Pa). This screening was completed with the evaluation of the possible mode of action of the extracts by testing the membrane permeability of these bacterial strains. The data collected indicate that the bacterial strains tested were sensitive to the extracts to varying degrees, except Cassia sieberiana DC and Pseudocedrela kotschyi extracts. For the active extracts, inhibition diameters ranged from 18.33 mm to 7 mm. With the exception of Escherichia coli, all strains were sensitive to the aqueous and hydroethanolic extracts of Anacardium occidentale. MICs vary between 3.37 and 25 mg/ml. Membrane permeability test data show that all active extracts affect the bacterial strains tested by attacking the stability of their outer membrane. For all active extracts, the high percentage of membrane destabilization of the bacteria is significantly (p < 0.05) better than that of cefixime used as a reference. Thus, it appears that these extracts can destroy Gram-negative bacteria and increase the fluidity and permeability of their cytoplasmic membrane. The knowledge of the mechanism of action of these extracts is an interesting contribution to the fundamental knowledge on the alternative that medicinal plants represent to antibiotics. These extracts can be used in the management of infectious diarrhea.
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26
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Pan C, Yue H, Zhu L, Ma GH, Wang HL. Prophylactic vaccine delivery systems against epidemic infectious diseases. Adv Drug Deliv Rev 2021; 176:113867. [PMID: 34280513 PMCID: PMC8285224 DOI: 10.1016/j.addr.2021.113867] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/20/2021] [Accepted: 07/11/2021] [Indexed: 01/04/2023]
Abstract
Prophylactic vaccines have evolved from traditional whole-cell vaccines to safer subunit vaccines. However, subunit vaccines still face problems, such as poor immunogenicity and low efficiency, while traditional adjuvants are usually unable to meet specific response needs. Advanced delivery vectors are important to overcome these barriers; they have favorable safety and effectiveness, tunable properties, precise location, and immunomodulatory capabilities. Nevertheless, there has been no systematic summary of the delivery systems to cover a wide range of infectious pathogens. We herein summarized and compared the delivery systems for major or epidemic infectious diseases caused by bacteria, viruses, fungi, and parasites. We also included the newly licensed vaccines (e.g., COVID-19 vaccines) and those close to licensure. Furthermore, we highlighted advanced delivery systems with high efficiency, cross-protection, or long-term protection against epidemic pathogens, and we put forward prospects and thoughts on the development of future prophylactic vaccines.
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Affiliation(s)
- Chao Pan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, Beijing 100071, PR China
| | - Hua Yue
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Li Zhu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, Beijing 100071, PR China
| | - Guang-Hui Ma
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Heng-Liang Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, Beijing 100071, PR China.
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27
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Khalil I, Walker R, Porter CK, Muhib F, Chilengi R, Cravioto A, Guerrant R, Svennerholm AM, Qadri F, Baqar S, Kosek M, Kang G, Lanata C, Armah G, Wierzba T, Hasso-Agopsowicz M, Giersing B, Louis Bourgeois A. Enterotoxigenic Escherichia coli (ETEC) vaccines: Priority activities to enable product development, licensure, and global access. Vaccine 2021; 39:4266-4277. [PMID: 33965254 PMCID: PMC8273896 DOI: 10.1016/j.vaccine.2021.04.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/06/2021] [Accepted: 04/09/2021] [Indexed: 02/08/2023]
Abstract
Diarrhoeal disease attributable to enterotoxigenic Escherichia coli (ETEC) causes substantial morbidity and mortality predominantly in paediatric populations in low- and middle-income countries. In addition to acute illness, there is an increasing appreciation of the long-term consequences of enteric infections, including ETEC, on childhood growth and development. Provision of potable water and sanitation and appropriate clinical care for acute illness are critical to reduce the ETEC burden. However, these interventions are not always practical and may not achieve equitable and sustainable coverage. Vaccination may be the most cost-effective and equitable means of primary prevention; however, additional data are needed to accelerate the investment and guide the decision-making process for ETEC vaccines. First, to understand and quantify the ETEC disease burden, additional data are needed on the association between ETEC infection and physical and cognitive stunting as well as delayed educational attainment. Furthermore, the role of inappropriate or inadequate antibiotic treatment of ETEC-attributable diarrhoea may contribute to the development of antimicrobial resistance (AMR) and needs further elucidation. An ETEC vaccine that mitigates acute diarrhoeal illness and minimizes the longer-term disease manifestations could have significant public health impact and be a cost-effective countermeasure. Herein we review the ETEC vaccine pipeline, led by candidates compatible with the general parameters of the Preferred Product Characteristics (PPC) recently developed by the World Health Organization. Additionally, we have developed an ETEC Vaccine Development Strategy to provide a framework to underpin priority activities for researchers, funders and vaccine manufacturers, with the goal of addressing globally unmet data needs in the areas of research, product development, and policy, as well as commercialization and delivery. The strategy also aims to guide prioritization and co-ordination of the priority activities needed to minimize the timeline to licensure and use of ETEC vaccines, especially in in low- and middle-income countries, where they are most urgently needed.
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Affiliation(s)
| | | | | | | | - Roma Chilengi
- Centre for Infectious Disease Research in Zambia, Zambia
| | | | | | | | | | - Shahida Baqar
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, USA
| | | | | | | | - George Armah
- Noguchi Memorial Institute for Medical Research, Ghana
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Pig vaccination strategies based on enterotoxigenic Escherichia coli toxins. Braz J Microbiol 2021; 52:2499-2509. [PMID: 34244980 PMCID: PMC8270777 DOI: 10.1007/s42770-021-00567-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 06/29/2021] [Indexed: 11/16/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) are responsible for diarrhea in humans as well as in farm animals. ETEC infections in newborn, suckling, and especially in post-weaning piglets are associated with reduced growth rate, morbidity, and mortality. ETEC express virulence factors as adhesin and enterotoxins that play a central role in the pathogenic process. Adhesins associated with pigs are of diverse type being either fimbrial or non-fimbrial. Enterotoxins belong to two groups: heat-labile (LT) and heat-stable (ST). Heterogeneity of ETEC strains encompass expression of various fimbriae (F4, F5, F6, F18, and F41) and enterotoxins (LT, STa, STb, and EAST1). In the late years, attempts to immunize animals against neonatal and post-weaning diarrhea were focused on the development of anti-adhesin strategies as this is the initial step of ETEC pathogenesis. Although those vaccines demonstrated some protection against ETEC infections, as enterotoxins are pivotal to the virulence of ETEC, a new generation of vaccinal molecules, which include adhesin and one or more enterotoxins, were recently tested. Some of these newly developed chimeric fusion proteins are intended to control as well human diarrhea as enterotoxins are more or less common with the ones found in pigs. As these could not be tested in the natural host (human), either a mouse or pig model was substituted to evaluate the protection efficacy. For the advancement of pig vaccine, mice were sometimes used for preliminary testing. This review summarizes advances in the anti-enterotoxin immunization strategies considered in the last 10 years.
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29
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Mondal I, Bhakat D, Chowdhury G, Manna A, Samanta S, Deb AK, Mukhopadhyay AK, Chatterjee NS. Distribution of virulence factors and its relatedness towards the antimicrobial response of enterotoxigenic Escherichia coli strains isolated from patients in Kolkata, India. J Appl Microbiol 2021; 132:675-686. [PMID: 34242448 DOI: 10.1111/jam.15206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 06/11/2021] [Accepted: 06/29/2021] [Indexed: 12/14/2022]
Abstract
AIM Enterotoxigenic Escherichia coli (ETEC) is one of the most widely recognized diarrhoeal pathogens in developing countries. The advancement of ETEC vaccine development depends on the antigenic determinants of the ETEC isolates from a particular geographical region. So, the aim here was to comprehend the distribution of virulence determinants of the clinical ETEC strains of this region. Additionally, an attempt was made to find any correlation with the antimicrobial response pattern. METHODS AND RESULTS Multiplex PCR was employed to identify virulence determinants followed by confirmatory singleplex PCR. For observation of antibiotic response, the Kirby-Bauer method was used. Out of 379 strains, 46% of strains harboured both the enterotoxins ST and LT, whereas 15% were LT only. Among the major colonization factors (CFs), CS6 (41%) was the most prevalent followed by CFA/I (35%) and CFA/III was the lowest (3%). Among the minor CFs, CS21 (25%) was most prevalent, while CS15 showed the lowest (3%) presence. Among the non-classical virulence factors, EatA (69%) was predominant. ETEC strains harbouring CS6 showed resistance towards the commonly used drug Ciprofloxacin (70%). CONCLUSION CS6 and elt+est toxin genes co-occurred covering 51% of the isolates. CS21 was found in most strains with est genes (43%). EatA was found to occur frequently when ST was present alone or with LT. CS6-harbouring strains showed an independent correlation to antimicrobial resistance. SIGNIFICANCE AND IMPACT OF THE STUDY This study would aid in identifying the commonly circulating ETEC isolates of Kolkata, India, and their prevalent virulence determinants. Knowledge of antibiotic resistance patterns would also help in the appropriate use of antibiotics. Furthermore, the study would aid in identifying the multivalent antigens suitable for region-specific ETEC vaccines with maximum coverage.
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Affiliation(s)
- Indranil Mondal
- Division of Biochemistry, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Debjyoti Bhakat
- Division of Biochemistry, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Goutam Chowdhury
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asis Manna
- Infectious Diseases and Beliaghata General Hospital, Kolkata, India
| | - Sandip Samanta
- Dr. B.C.Roy Post Graduate Institute of Pediatric Sciences, Kolkata, India
| | - Alok Kumar Deb
- Division of Epidemiology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asish Kumar Mukhopadhyay
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
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Hwang SB, Chelliah R, Kang JE, Rubab M, Banan-MwineDaliri E, Elahi F, Oh DH. Role of Recent Therapeutic Applications and the Infection Strategies of Shiga Toxin-Producing Escherichia coli. Front Cell Infect Microbiol 2021; 11:614963. [PMID: 34268129 PMCID: PMC8276698 DOI: 10.3389/fcimb.2021.614963] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 05/07/2021] [Indexed: 12/17/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a global foodborne bacterial pathogen that is often accountable for colon disorder or distress. STEC commonly induces severe diarrhea in hosts but can cause critical illnesses due to the Shiga toxin virulence factors. To date, there have been a significant number of STEC serotypes have been evolved. STECs vary from nausea and hemorrhoid (HC) to possible lethal hemolytic-based uremic syndrome (HUS), thrombotic thrombocytopenic purpura (TTP). Inflammation-based STEC is usually a foodborne illness with Shiga toxins (Stx 1 and 2) thought to be pathogenesis. The STEC's pathogenicity depends significantly on developing one or more Shiga toxins, which can constrain host cell protein synthesis leading to cytotoxicity. In managing STEC infections, antimicrobial agents are generally avoided, as bacterial damage and discharge of accumulated toxins are thought the body. It has also been documented that certain antibiotics improve toxin production and the development of these species. Many different groups have attempted various therapies, including toxin-focused antibodies, toxin-based polymers, synbiotic agents, and secondary metabolites remedies. Besides, in recent years, antibiotics' efficacy in treating STEC infections has been reassessed with some encouraging methods. Nevertheless, the primary role of synbiotic effectiveness (probiotic and prebiotic) against pathogenic STEC and other enteropathogens is less recognized. Additional studies are required to understand the mechanisms of action of probiotic bacteria and yeast against STEC infection. Because of the consensus contraindication of antimicrobials for these bacterial pathogens, the examination was focused on alternative remedy strategies for STEC infections. The rise of novel STEC serotypes and approaches employed in its treatment are highlighted.
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Affiliation(s)
- Su-bin Hwang
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
| | - Ramachandran Chelliah
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
| | - Ji Eun Kang
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
| | - Momna Rubab
- School of Food and Agricultural Sciences, University of Management and Technology, Lahore, Pakistan
| | - Eric Banan-MwineDaliri
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
| | - Fazle Elahi
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
| | - Deog-Hwan Oh
- Department of Food Science and Biotechnology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon, South Korea
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31
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Escherichia coli Strains Producing Selected Bacteriocins Inhibit Porcine Enterotoxigenic Escherichia coli (ETEC) under both In Vitro and In Vivo Conditions. Appl Environ Microbiol 2021; 87:e0312120. [PMID: 33962981 DOI: 10.1128/aem.03121-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) and Shiga toxin-producing E. coli (STEC) strains are the causative agents of severe foodborne diseases in both humans and animals. In this study, porcine pathogenic E. coli strains (n = 277) as well as porcine commensal strains (n = 188) were tested for their susceptibilities to 34 bacteriocin monoproducers to identify the most suitable bacteriocin types inhibiting porcine pathogens. Under in vitro conditions, the set of pathogenic E. coli strains was found to be significantly more susceptible to the majority of tested bacteriocins than commensal E. coli. Based on the production of bacteriocins with specific activity against pathogens, three potentially probiotic commensal E. coli strains of human origin were selected. These strains were found to be able to outcompete ETEC strains expressing F4 or F18 fimbriae in liquid culture and also decreased the severity and duration of diarrhea in piglets during experimental ETEC infection as well as pathogen numbers on the last day of in vivo experimentation. While the extents of the probiotic effect were different for each strain, the cocktail of all three strains showed the most pronounced beneficial effects, suggesting synergy between the tested E. coli strains. IMPORTANCE Increasing levels of antibiotic resistance among bacteria also increase the need for alternatives to conventional antibiotic treatment. Pathogenic Escherichia coli represents a major diarrheic infectious agent of piglets in their postweaning period; however, available measures to control these infections are limited. This study describes three novel E. coli strains producing antimicrobial compounds (bacteriocins) that actively inhibit a majority of toxigenic E. coli strains. The beneficial effect of three potentially probiotic E. coli strains was demonstrated under both in vitro and in vivo conditions. The novel probiotic candidates may be used as prophylaxis during piglets' postweaning period to overcome common infections caused by E. coli.
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32
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Rogawski McQuade ET, Liu J, Kang G, Kosek MN, Lima AAM, Bessong PO, Samie A, Haque R, Mduma ER, Shrestha S, Leite JP, Bodhidatta L, Iqbal N, Page N, Kiwelu I, Bhutta Z, Ahmed T, Houpt ER, Platts-Mills JA. Protection From Natural Immunity Against Enteric Infections and Etiology-Specific Diarrhea in a Longitudinal Birth Cohort. J Infect Dis 2021; 222:1858-1868. [PMID: 31984416 PMCID: PMC7653087 DOI: 10.1093/infdis/jiaa031] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/22/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The degree of protection conferred by natural immunity is unknown for many enteropathogens, but it is important to support the development of enteric vaccines. METHODS We used the Andersen-Gill extension of the Cox model to estimate the effects of previous infections on the incidence of subsequent subclinical infections and diarrhea in children under 2 using quantitative molecular diagnostics in the MAL-ED cohort. We used cross-pathogen negative control associations to correct bias due to confounding by unmeasured heterogeneity of exposure and susceptibility. RESULTS Prior rotavirus infection was associated with a 50% lower hazard (calibrated hazard ratio [cHR], 0.50; 95% confidence interval [CI], 0.41-0.62) of subsequent rotavirus diarrhea. Strong protection was evident against Cryptosporidium diarrhea (cHR, 0.32; 95% CI, 0.20-0.51). There was also protection due to prior infections for norovirus GII (cHR against diarrhea, 0.67; 95% CI, 0.49-0.91), astrovirus (cHR, 0.62; 95% CI, 0.48-0.81), and Shigella (cHR, 0.79; 95% CI, 0.65-0.95). Minimal protection was observed for other bacteria, adenovirus 40/41, and sapovirus. CONCLUSIONS Natural immunity was generally stronger for the enteric viruses than bacteria, potentially due to less antigenic diversity. Vaccines against major causes of diarrhea may be feasible but likely need to be more immunogenic than natural infection.
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Affiliation(s)
- Elizabeth T Rogawski McQuade
- Department of Public Health Sciences, University of Virginia, Charlottesville, Virgina, USA.,Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virgina, USA
| | - Jie Liu
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virgina, USA
| | | | - Margaret N Kosek
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virgina, USA.,Asociación Benéfica PRISMA, Iquitos, Peru
| | | | | | | | - Rashidul Haque
- International Centre for Diarrheal Disease Research, Dhaka, Bangladesh
| | | | | | | | - Ladaporn Bodhidatta
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | | | - Nicola Page
- National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Ireen Kiwelu
- Kilimanjaro Clinical Research Institute, Moshi, Tanzania
| | | | - Tahmeed Ahmed
- International Centre for Diarrheal Disease Research, Dhaka, Bangladesh
| | - Eric R Houpt
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virgina, USA
| | - James A Platts-Mills
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virgina, USA
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33
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Mottram L, Lundgren A, Svennerholm AM, Leach S. A Systems Biology Approach Identifies B Cell Maturation Antigen (BCMA) as a Biomarker Reflecting Oral Vaccine Induced IgA Antibody Responses in Humans. Front Immunol 2021; 12:647873. [PMID: 33828557 PMCID: PMC8019727 DOI: 10.3389/fimmu.2021.647873] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 02/19/2021] [Indexed: 12/11/2022] Open
Abstract
Vaccines against enteric diseases could improve global health. Despite this, only a few oral vaccines are currently available for human use. One way to facilitate such vaccine development could be to identify a practical and relatively low cost biomarker assay to assess oral vaccine induced primary and memory IgA immune responses in humans. Such an IgA biomarker assay could complement antigen-specific immune response measurements, enabling more oral vaccine candidates to be tested, whilst also reducing the work and costs associated with early oral vaccine development. With this in mind, we take a holistic systems biology approach to compare the transcriptional signatures of peripheral blood mononuclear cells isolated from volunteers, who following two oral priming doses with the oral cholera vaccine Dukoral®, had either strong or no vaccine specific IgA responses. Using this bioinformatical method, we identify TNFRSF17, a gene encoding the B cell maturation antigen (BCMA), as a candidate biomarker of oral vaccine induced IgA immune responses. We then assess the ability of BCMA to reflect oral vaccine induced primary and memory IgA responses using an ELISA BCMA assay on a larger number of samples collected in clinical trials with Dukoral® and the oral enterotoxigenic Escherichia coli vaccine candidate ETVAX. We find significant correlations between levels of BCMA and vaccine antigen-specific IgA in antibodies in lymphocyte secretion (ALS) specimens, as well as with proportions of circulating plasmablasts detected by flow cytometry. Importantly, our results suggest that levels of BCMA detected early after primary mucosal vaccination may be a biomarker for induction of long-lived vaccine specific memory B cell responses, which are otherwise difficult to measure in clinical vaccine trials. In addition, we find that ALS-BCMA responses in individuals vaccinated with ETVAX plus the adjuvant double mutant heat-labile toxin (dmLT) are significantly higher than in subjects given ETVAX only. We therefore propose that as ALS-BCMA responses may reflect the total vaccine induced IgA responses to oral vaccination, this BCMA ELISA assay could also be used to estimate the total adjuvant effect on vaccine induced-antibody responses, independently of antigen specificity, further supporting the usefulness of the assay.
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Affiliation(s)
- Lynda Mottram
- Gothenburg University Vaccine Research Institute (GUVAX), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anna Lundgren
- Gothenburg University Vaccine Research Institute (GUVAX), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ann-Mari Svennerholm
- Gothenburg University Vaccine Research Institute (GUVAX), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Susannah Leach
- Gothenburg University Vaccine Research Institute (GUVAX), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Clinical Pharmacology, Sahlgrenska University Hospital, Gothenburg, Sweden
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34
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Northrup GR, Qian L, Bruxvoort K, Marx FM, Whittles LK, Lewnard JA. Inference of Naturally Acquired Immunity Using a Self-matched Negative-Control Design. Epidemiology 2021; 32:168-178. [PMID: 33337670 PMCID: PMC7850593 DOI: 10.1097/ede.0000000000001305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 11/17/2020] [Indexed: 11/25/2022]
Abstract
Host adaptive immune responses may protect against infection or disease when a pathogen is repeatedly encountered. The hazard ratio of infection or disease, given previous infection, is typically sought to estimate the strength of protective immunity. However, variation in individual exposure or susceptibility to infection may introduce frailty bias, whereby a tendency for infections to recur among individuals with greater risk confounds the causal association between previous infection and susceptibility. We introduce a self-matched "case-only" inference method to control for unmeasured individual heterogeneity, making use of negative-control endpoints not attributable to the pathogen of interest. To control for confounding, this method compares event times for endpoints due to the pathogen of interest and negative-control endpoints during counterfactual risk periods, defined according to individuals' infection history. We derive a standard Mantel-Haenszel (matched) odds ratio conveying the effect of prior infection on time to recurrence. We compare performance of this approach to several proportional hazards modeling frameworks and estimate statistical power of the proposed strategy under various conditions. In an example application, we use the proposed method to reestimate naturally acquired protection against rotavirus gastroenteritis using data from previously published cohort studies. This self-matched negative-control design may present a flexible alternative to existing approaches for analyzing naturally acquired immunity, as well as other exposures affecting the distribution of recurrent event times.
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Affiliation(s)
- Graham R. Northrup
- From the Center for Computational Biology, College of Engineering, University of California, Berkeley, Berkeley, CA
| | - Lei Qian
- Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA
| | - Katia Bruxvoort
- Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA
| | - Florian M. Marx
- Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Desmond Tutu Tuberculosis Centre, Stellenbosch University, Cape Town, South Africa
- DST-NRF South African Centre of Excellence and Epidemiological Modelling and Analysis, Stellenbosch University, Stellenbosch, South Africa
| | - Lilith K. Whittles
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
- NIHR Health Protection Research Unit in Modelling Methodology, School of Public Health, Imperial College London, London, United Kingdom
| | - Joseph A. Lewnard
- From the Center for Computational Biology, College of Engineering, University of California, Berkeley, Berkeley, CA
- Division of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, CA
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA
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35
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Establishment and Validation of Pathogenic CS17 + and CS19 + Enterotoxigenic Escherichia coli Challenge Models in the New World Primate Aotus nancymaae. Infect Immun 2021; 89:IAI.00479-20. [PMID: 33288648 DOI: 10.1128/iai.00479-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/23/2020] [Indexed: 11/20/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a common cause of diarrheal illness in the military, travelers, and children living in low- to middle-income countries. Increased antibiotic resistance, the absence of a licensed vaccine, and the lack of broadly practical therapeutics perpetuate the significant health and financial burden resulting from ETEC infection. A critical step in the evaluation of vaccines and therapeutics is preclinical screening in a relevant animal disease model that closely replicates human disease. We previously developed a diarrheal model of class 5a colonization factor (CF) CFA/I-expressing ETEC in the New World owl monkey species Aotus nancymaae using ETEC strain H10407. In order to broaden the use of the model, we report here on the development of A. nancymaae models of ETEC expressing the class 5b CFs CS17 and CS19 with strains LSN03-016011/A and WS0115A, respectively. For both models, we observed diarrheal attack rates of ≥80% after oral inoculation with 5 × 1011 CFU of bacteria. These models will aid in assessing the efficacy of future ETEC vaccine candidates and therapeutics.
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36
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Brubaker J, Zhang X, Bourgeois AL, Harro C, Sack DA, Chakraborty S. Intestinal and systemic inflammation induced by symptomatic and asymptomatic enterotoxigenic E. coli infection and impact on intestinal colonization and ETEC specific immune responses in an experimental human challenge model. Gut Microbes 2021; 13:1-13. [PMID: 33645430 PMCID: PMC7919917 DOI: 10.1080/19490976.2021.1891852] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 02/02/2021] [Accepted: 02/08/2021] [Indexed: 02/07/2023] Open
Abstract
Recent studies have gained a better appreciation of the potential impacts of enteric infections beyond symptomatic diarrhea. It is recognized that infections by several enteropathogens could be associated with growth deficits in children and intestinal and systemic inflammation may play an important underlying role. With enterotoxigenic E. coli (ETEC) being one of the leading causes of diarrhea among children in the developing world and important contributor to stunting, a better understanding of the impact of ETEC infection beyond diarrhea is timely and greatly needed. To address this, we evaluated if ETEC infection induces intestinal and systemic inflammation and its impact on colonization and immune responses to ETEC vaccine-specific antigens in a dose descending experimental human challenge model using ETEC strain H10407. This study demonstrates that the concentrations of myeloperoxidase (MPO) in stool and intestinal fatty acid-binding protein (an indicator of compromised intestinal epithelial integrity) in serum, significantly increased following ETEC infection in both diarrhea and asymptomatic cases and the magnitudes and kinetics of MPO are dose and clinical outcome dependent. Cytokines IL-17A and IFN-γ were significantly increased in serum post-ETEC challenge. In addition, higher pre-challenge concentrations of cytokines IL-10 and GM-CSF were associated with protection from ETEC diarrhea. Interestingly, higher MPO concentrations were associated with higher intestinal colonization of ETEC and lower seroconversions of colonization factor I antigen, but the reverse was noted for seroconversions to heat-labile toxin B-subunit. Together this study has important implications for understanding the acute and long-term negative health outcomes associated with ETEC infection.
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Affiliation(s)
- Jessica Brubaker
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Xueyan Zhang
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - A. Louis Bourgeois
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
- PATH, Center for Vaccine Innovation and Access, Washington, DC, 20001, USA
| | - Clayton Harro
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - David A Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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37
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Teh AYH, Cavacini L, Hu Y, Kumru OS, Xiong J, Bolick DT, Joshi SB, Grünwald-Gruber C, Altmann F, Klempner M, Guerrant RL, Volkin DB, Wang Y, Ma JKC. Investigation of a monoclonal antibody against enterotoxigenic Escherichia coli, expressed as secretory IgA1 and IgA2 in plants. Gut Microbes 2021; 13:1-14. [PMID: 33439092 PMCID: PMC7833773 DOI: 10.1080/19490976.2020.1859813] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/09/2020] [Accepted: 11/23/2020] [Indexed: 02/04/2023] Open
Abstract
Passive immunization with antibodies is a promising approach against enterotoxigenic Escherichia coli diarrhea, a prevalent disease in LMICs. The objective of this study was to investigate expression of a monoclonal anti-ETEC CfaE secretory IgA antibody in N. benthamiana plants, with a view to facilitating access to ETEC passive immunotherapy. SIgA1 and SIgA2 forms of mAb 68-81 were produced by co-expressing the light and engineered heavy chains with J chain and secretory component in N. benthamiana. Antibody expression and assembly were compared with CHO-derived antibodies by SDS-PAGE, western blotting, size-exclusion chromatography and LC-MS peptide mapping. N-linked glycosylation was assessed by rapid fluorescence/mass spectrometry and LC-ESI-MS. Susceptibility to gastric digestion was assessed in an in vitro model. Antibody function was compared for antigen binding, a Caco-2 cell-based ETEC adhesion assay, an ETEC hemagglutination inhibition assay and a murine in vivo challenge study. SIgA1 assembly appeared superior to SIgA2 in plants. Both sub-classes exhibited resistance to degradation by simulated gastric fluid, comparable to CHO-produced 68-61 SIgA1. The plant expressed SIgAs had more homogeneous N-glycosylation than CHO-derived SIgAs, but no alteration of in vitro functional activity was observed, including antibodies expressed in a plant line engineered for mammalian-like N glycosylation. The plant-derived SIgA2 mAb demonstrated protection against diarrhea in a murine infection model. Although antibody yield and purification need to be optimized, anti-ETEC SIgA antibodies produced in a low-cost plant platform are functionally equivalent to CHO antibodies, and provide promise for passive immunotherapy in LMICs.
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MESH Headings
- Animals
- Antibodies, Bacterial/genetics
- Antibodies, Bacterial/immunology
- Antibodies, Bacterial/metabolism
- Antibodies, Bacterial/therapeutic use
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/metabolism
- Antibodies, Monoclonal/therapeutic use
- Antibody Affinity
- Bacterial Adhesion/drug effects
- Caco-2 Cells
- Enterotoxigenic Escherichia coli/immunology
- Escherichia coli Infections/microbiology
- Escherichia coli Infections/therapy
- Gastric Acid/metabolism
- Glycosylation
- Humans
- Immunoglobulin A, Secretory/genetics
- Immunoglobulin A, Secretory/immunology
- Immunoglobulin A, Secretory/metabolism
- Immunoglobulin A, Secretory/therapeutic use
- Immunotherapy
- Mice
- Plants, Genetically Modified
- Nicotiana/genetics
- Nicotiana/metabolism
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Affiliation(s)
- Audrey Y-H Teh
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George’s University of London, London, UK
| | - Lisa Cavacini
- MassBiologics of the University of Massachusetts Medical School, Boston, MA, USA
| | - Yue Hu
- Vaccine Analytics and Formulation Center, Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Ozan S. Kumru
- Vaccine Analytics and Formulation Center, Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Jian Xiong
- Vaccine Analytics and Formulation Center, Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - David T. Bolick
- Division of Infectious Disease and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Sangeeta B. Joshi
- Vaccine Analytics and Formulation Center, Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Clemens Grünwald-Gruber
- Department for Chemistry, Division of Biochemistry, Universität Für Bodenkultur Wien, Vienna, Austria
| | - Friedrich Altmann
- Department for Chemistry, Division of Biochemistry, Universität Für Bodenkultur Wien, Vienna, Austria
| | - Mark Klempner
- MassBiologics of the University of Massachusetts Medical School, Boston, MA, USA
| | - Richard L. Guerrant
- Division of Infectious Disease and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - David B. Volkin
- Vaccine Analytics and Formulation Center, Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Yang Wang
- MassBiologics of the University of Massachusetts Medical School, Boston, MA, USA
| | - Julian K-C. Ma
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George’s University of London, London, UK
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Harutyunyan S, Neuhauser I, Mayer A, Aichinger M, Szijártó V, Nagy G, Nagy E, Girardi P, Malinoski FJ, Henics T. Characterization of ShigETEC, a Novel Live Attenuated Combined Vaccine against Shigellae and ETEC. Vaccines (Basel) 2020; 8:vaccines8040689. [PMID: 33207794 PMCID: PMC7712393 DOI: 10.3390/vaccines8040689] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 11/16/2022] Open
Abstract
Background: Shigella spp. and enterotoxigenic Escherichia coli (ETEC) remain the two leading bacterial causes of diarrheal diseases worldwide. Attempts to develop preventive vaccines against Shigella and ETEC have not yet been successful. The major challenge for a broad Shigella vaccine is the serotype-specific immune response to the otherwise protective LPS O-antigen. ETEC vaccines mainly rely on the heat-labile enterotoxin (LT), while heat-stable toxin (ST) has also been shown to be an important virulence factor. Methods: We constructed a combined Shigella and ETEC vaccine (ShigETEC) based on a live attenuated Shigella strain rendered rough and non-invasive with heterologous expression of two ETEC antigens, LTB and a detoxified version of ST (STN12S). This new vaccine strain was characterized and tested for immunogenicity in relevant animal models. Results: Immunization with ShigETEC resulted in serotype independent protection in the mouse lung shigellosis model and induced high titer IgG and IgA antibodies against bacterial lysates, and anti-ETEC toxin antibodies with neutralizing capacity. Conclusions: ShigETEC is a promising oral vaccine candidate against Shigella and ETEC infections and currently in Phase 1 testing.
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Affiliation(s)
- Shushan Harutyunyan
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Irene Neuhauser
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Alexandra Mayer
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Michael Aichinger
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Valéria Szijártó
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Gábor Nagy
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
- CEBINA GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria
| | - Eszter Nagy
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
- CEBINA GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria
| | - Petra Girardi
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Frank J. Malinoski
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
| | - Tamás Henics
- Eveliqure Biotechnologies GmbH, Karl-Farkas-Gasse 22, 1030 Vienna, Austria; (S.H.); (I.N.); (A.M.); (M.A.); (V.S.); (G.N.); (E.N.); (P.G.); (F.J.M.)
- Correspondence: ; Tel.: +43-1-909-2208-3313
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Cross-Reactivity, Epitope Mapping, and Potency of Monoclonal Antibodies to Class 5 Fimbrial Tip Adhesins of Enterotoxigenic Escherichia coli. Infect Immun 2020; 88:IAI.00246-20. [PMID: 32839190 PMCID: PMC7573445 DOI: 10.1128/iai.00246-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/08/2020] [Indexed: 12/26/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a leading diarrheagenic bacterial pathogen among travelers and children in resource-limited regions. Adherence to host intestinal cells mediated by ETEC fimbriae is believed to be a critical first step in ETEC pathogenesis. These fimbriae are categorized into related classes based on sequence similarity, with members of the class 5 fimbrial family being the best characterized. The eight related members of the ETEC class 5 fimbrial family are subdivided into three subclasses (5a, 5b, and 5c) that share similar structural arrangements, including a fimbrial tip adhesin. Enterotoxigenic Escherichia coli (ETEC) is a leading diarrheagenic bacterial pathogen among travelers and children in resource-limited regions. Adherence to host intestinal cells mediated by ETEC fimbriae is believed to be a critical first step in ETEC pathogenesis. These fimbriae are categorized into related classes based on sequence similarity, with members of the class 5 fimbrial family being the best characterized. The eight related members of the ETEC class 5 fimbrial family are subdivided into three subclasses (5a, 5b, and 5c) that share similar structural arrangements, including a fimbrial tip adhesin. However, sequence variability among the class 5 adhesins may hinder the generation of cross-protective antibodies. To better understand functional epitopes of the class 5 adhesins and their ability to induce intraclass antibody responses, we produced 28 antiadhesin monoclonal antibodies (MAbs) to representative adhesins CfaE, CsbD, and CotD, respectively. We determined the MAb cross-reactivities, localized the epitopes, and measured functional activities as potency in inhibition of hemagglutination induced by class 5 fimbria-bearing ETEC. The MAbs’ reactivities to a panel of class 5 adhesins in enzyme-linked immunosorbent assays (ELISAs) revealed several reactivity patterns, including individual adhesin specificity, intrasubclass specificity, intersubclass specificity, and class-wide cross-reactivity, suggesting that some conserved epitopes, including two conserved arginines, are shared by the class 5 adhesins. However, the cross-reactive MAbs had functional activities limited to strains expressing colonization factor antigen I (CFA/I), coli surface antigen 17 (CS17), or CS1, suggesting that the breadth of functional activities of the MAbs was more restricted than the repertoire of cross-reactivities measured by ELISA. The results imply that multivalent adhesin-based ETEC vaccines or prophylactics need more than one active component to reach broad protection.
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Wierzba TF. Implications and measurement of herd protection (indirect effects) for enteric vaccine development. Vaccine 2020; 37:4775-4777. [PMID: 31358237 DOI: 10.1016/j.vaccine.2019.02.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/10/2019] [Accepted: 02/25/2019] [Indexed: 12/11/2022]
Abstract
Diarrhea remains one of the top five causes of disease and death among young children in developing nations. Fortunately, scientists are making progress developing vaccines against enterotoxigenic E. coli (ETEC) and Shigella, two of the leading diarrhea pathogens. As vaccine developers start to consider field efficacy trials of these vaccines, they should be aware of the importance of evaluating not only vaccine direct effects on the immunized, but also the herd effects that vaccination can afford to the unimmunized in a community. In a workshop held at the conference titled "Vaccines against Shigella and ETEC (VASE)", we described to participants what herd effects are and we presented on methods used in cholera and rotavirus studies that could be useful for future ETEC and Shigella vaccine trials conducted in low and middle-income nations. We also presented evidence on the effects of vaccine herd effects for estimates of vaccine cost-effectiveness.
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Affiliation(s)
- Thomas F Wierzba
- Wake Forest School of Medicine, Department of Internal Medicine, Section on Infectious Diseases, 1 Medical Center Blvd., Winston Salem, VA 27157-1024, United States; PATH, Enteric Vaccines Initiative, 455 Massachusetts Ave NW, Washington, DC 20001-2785, United States.
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Preclinical optimization of an enterotoxigenic Escherichia coli adjuvanted subunit vaccine using response surface design of experiments. NPJ Vaccines 2020; 5:83. [PMID: 32983577 PMCID: PMC7486917 DOI: 10.1038/s41541-020-00228-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 08/10/2020] [Indexed: 12/19/2022] Open
Abstract
Enterotoxigenic E. coli (ETEC) is a leading cause of moderate-to-severe diarrhoea. ETEC colonizes the intestine through fimbrial tip adhesin colonization factors and produces heat-stable and/or heat-labile (LT) toxins, stimulating fluid and electrolyte release leading to watery diarrhoea. We reported that a vaccine containing recombinant colonization factor antigen (CfaEB) targeting fimbrial tip adhesin of the colonization factor antigen I (CFA/I) and an attenuated LT toxoid (dmLT) elicited mucosal and systemic immune responses against both targets. Additionally, the toll-like receptor 4 ligand second-generation lipid adjuvant (TLR4-SLA) induced a potent mucosal response, dependent on adjuvant formulation. However, a combination of vaccine components at their respective individual optimal doses may not achieve the optimal immune profile. We studied a subunit ETEC vaccine prototype in mice using a response surface design of experiments (DoE), consisting of 64 vaccine dose-combinations of CfaEB, dmLT and SLA in four formulations (aqueous, aluminium oxyhydroxide, squalene-in-water stable nanoemulsion [SE] or liposomes containing the saponin Quillaja saponaria-21 [LSQ]). Nine readouts focusing on antibody functionality and plasma cell response were selected to profile the immune response of parenterally administered ETEC vaccine prototype. The data were integrated in a model to identify the optimal dosage of each vaccine component and best formulation. Compared to maximal doses used in mouse models (10 µg CfaEB, 1 µg dmLT and 5 µg SLA), a reduction in the vaccine components up to 37%, 60% and 88% for CfaEB, dmLT and SLA, respectively, maintained or even maximized immune responses, with SE and LSQ the best formulations. The DoE approach can help determine the best vaccine composition with a limited number of experiments and may accelerate development of multi-antigen/component ETEC vaccines.
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Abstract
Enterotoxigenic Escherichia coli (ETEC) is a well-established cause of traveller's diarrhoea and occasional domestic foodborne illness outbreaks in the USA. Although ETEC are not detected by conventional stool culture methods used in clinical laboratories, syndromic culture-independent diagnostic tests (CIDTs) capable of detecting ETEC have become increasingly prevalent in the last decade. This study describes the epidemiology of ETEC infections reported to the Minnesota Department of Health (MDH) during 2016–2017. ETEC-positive stool specimens were submitted to MDH to confirm the presence of ETEC DNA by polymerase chain reaction (PCR). Cases were interviewed to ascertain illness and exposures. Contemporaneous Salmonella cases were used as a comparison group in a case-case comparison analysis of risk factors. Of 222 ETEC-positive specimens received by MDH, 108 (49%) were concordant by PCR. ETEC was the sixth most frequently reported bacterial enteric pathogen among a subset of CIDT-positive specimens. Sixty-nine (64%) laboratory-confirmed cases had an additional pathogen codetected with ETEC, including enteroaggregative E. coli (n = 40) and enteropathogenic E. coli (n = 39). Although travel is a risk factor for ETEC infection, only 43% of cases travelled internationally, providing evidence for ETEC as an underestimated source of domestically acquired enteric illness in the USA.
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Oishi W, Kato I, Hijikata N, Ushijima K, Ito R, Funamizu N, Nishimura O, Sano D. Inactivation kinetics modeling of Escherichia coli in concentrated urine for implementing predictive environmental microbiology in sanitation safety planning. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 268:110672. [PMID: 32383646 DOI: 10.1016/j.jenvman.2020.110672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/27/2020] [Accepted: 04/27/2020] [Indexed: 06/11/2023]
Abstract
Urine concentration (condensation) leads to the inactivation of pathogens in urine owing to a hyperosmotic environment. This study proposed an inactivation kinetic model of Escherichia coli (E. coli), a surrogate of human bacterial pathogens, in concentrated synthetic urine. The model parameters were obtained under an assumption that the inactivation rate of E. coli followed a binomial distribution, which made it possible to accurately simulate the time-course decay of E. coli in synthetic urine. The inactivation rate constant values obtained in concentrated urine samples, ammonium buffer solutions and carbonate buffer solutions indicated that the osmotic pressure was a relatively predominant cause for the inactivation of E. coli. The appropriate storage time was estimated using the approach of quantitative microbial risk assessment, which indicated that the 5-fold concentrated urine could be safely collected after 1-day storage when urea was hydrolyzed, whereas 91-hour storage was required for non-concentrated urine. The occupational risk was not negligible even with 6-month storage at 20 °C when urea was not hydrolyzed, which suggested that the urine storage styles should be clarified more minutely. The present study highlights the importance of "predictive environmental microbiology," which deals with inactivation kinetic models of microorganisms under varied environmental conditions to fully implement the hazard analysis and critical control point (HACCP) approach for the safe use of human excreta in agriculture.
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Affiliation(s)
- Wakana Oishi
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan
| | - Ikuo Kato
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan
| | - Nowaki Hijikata
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Kita-ku, Sapporo, Hokkaido, 060-8628, Japan
| | - Ken Ushijima
- Building Research Department, Hokkaido Research Organization, 3-1-20, Midorigaoka-higashi 1, Asahikawa, Hokkaido, 078-8801, Japan
| | - Ryusei Ito
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Kita-ku, Sapporo, Hokkaido, 060-8628, Japan
| | - Naoyuki Funamizu
- Muroran Institute of Technology, Mizumoto-cho, Muroran, Hokkaido, 050-8585, Japan
| | - Osamu Nishimura
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan
| | - Daisuke Sano
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan; Department of Frontier Sciences for Advanced Environment, Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan.
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You HS, Lee SH, Kang SS, Hyun SH. OmpA of Klebsiella pneumoniae ATCC 13883 induces pyroptosis in HEp-2 cells, leading to cell-cycle arrest and apoptosis. Microbes Infect 2020; 22:432-440. [PMID: 32569734 DOI: 10.1016/j.micinf.2020.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 06/08/2020] [Accepted: 06/08/2020] [Indexed: 01/23/2023]
Abstract
Klebsiella pneumoniae is an opportunistic pathogenic bacterium that commonly causes pneumonia in elderly people. OmpA, a toxin that is highly expressed in the outer membrane of the bacterium, is one of the primary factors implicated in the pulmonary pathogenesis of K. pneumoniae. To evaluate the associated pyroptosis mechanism of infection, the ompA gene was cloned, and the protein was expressed, extracted, and used to treat human larynx epithelial cells. We observed that OmpA induces reactive oxygen species production and cell-cycle arrest in the G2/M phase in host cells, leading to subsequent apoptosis. Moreover, OmpA was found to induce IL-1β and IL-18 production in host cells, resulting in caspase-1 activation, which simultaneously stimulated pyroptosis, thus leading to the death of the host cells. We next sought to examine differential gene expression via RNA sequencing to better elucidate the mechanisms associated with these cellular changes, and found that genes associated with these pathways were more highly expressed in OmpA-treated cells than in K. pneumoniae-infected cells. Thus, cell-cycle arrest, apoptosis, and pyroptosis may serve as the primary defenses employed by host cells against OmpA. These results provide novel insights into the host defense against K. pneumoniae infection.
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Affiliation(s)
- Hee Sang You
- Department of Biomedical Laboratory Science, Eulji University, School of Medicine, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea; Department of Senior Healthcare, BK21 Plus Program, Graduate School, Eulji University, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea
| | - Song Hee Lee
- Department of Biomedical Laboratory Science, Eulji University, School of Medicine, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea; Department of Senior Healthcare, BK21 Plus Program, Graduate School, Eulji University, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea
| | - Sang Sun Kang
- Department of Biology Education, Chungbuk National University, Chungdae-ro 1, Seowon-gu, Cheongju, Chungbuk, 28644, Republic of Korea
| | - Sung Hee Hyun
- Department of Biomedical Laboratory Science, Eulji University, School of Medicine, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea; Department of Senior Healthcare, BK21 Plus Program, Graduate School, Eulji University, 77, Gyeryong-ro, 771 beon-gil, Jung-gu, Daejeon, 34824, Republic of Korea.
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U-Omp19 from Brucella abortus increases dmLT immunogenicity and improves protection against Escherichia coli heat-labile toxin (LT) oral challenge. Vaccine 2020; 38:5027-5035. [PMID: 32536545 PMCID: PMC7327514 DOI: 10.1016/j.vaccine.2020.05.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 05/13/2020] [Accepted: 05/15/2020] [Indexed: 01/18/2023]
Abstract
Oral co-administration of dmLT with U-Omp19 increases dmLT immunogenicity. U-Omp19 oral co-delivery with dmLT induces anti-LT antibody responses. U-Omp19 co-administered with dmLT protects against oral challenge with LT. U-Omp19 can allow antigen dose sparing by oral route. U-Omp19 can be used as adjuvant in an oral vaccine formulation against ETEC.
Acute diarrhea disease caused by bacterial infections is a major global health problem. Enterotoxigenic Escherichia coli (ETEC) is one of the top causes of diarrhea-associated morbidity and mortality in young children and travelers to low-income countries. There are currently no licensed vaccines for ETEC. Induction of immunity at the site of entry of the bacteria is key to prevent infection. Current approaches to ETEC vaccines include a less toxic mutant form of E. coli heat-labile toxin (double-mutant heat-labile enterotoxin -dmLT-) with both antigenic and immunostimulatory properties. U-Omp19 is a protease inhibitor from Brucella spp. with immunostimulatory properties that has been used as oral adjuvant. In this work, we use U-Omp19 as adjuvant in an oral vaccine formulation against ETEC containing dmLT in outbred and inbred mice. To evaluate antigen dose sparing by U-Omp19 three different immunization protocols with three different doses of dmLT were evaluated. We demonstrated that U-Omp19 co-delivery increases anti-LT IgA in feces using a mid-dose of dmLT following a prime-boost protocol (after one or two boosts). Oral immunization with U-Omp19 induced protection against LT challenge when co-formulated with dmLT in CD-1 and BALB/c mice. Indeed, there was a significant increase in anti-LT IgG and IgA avidity after a single oral administration of dmLT plus U-Omp19 in comparison with dmLT delivered alone. Interestingly, sera from dmLT plus U-Omp19 vaccinated mice significantly neutralize LT effect on intestine inflammation in vivo compared with sera from the group immunized with dmLT alone. These results demonstrate the adjuvant capacity of U-Omp19 to increase dmLT immunogenicity by the oral route and support its use in an oral subunit vaccine formulation against ETEC.
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Thibau A, Dichter AA, Vaca DJ, Linke D, Goldman A, Kempf VAJ. Immunogenicity of trimeric autotransporter adhesins and their potential as vaccine targets. Med Microbiol Immunol 2020; 209:243-263. [PMID: 31788746 PMCID: PMC7247748 DOI: 10.1007/s00430-019-00649-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/19/2019] [Indexed: 12/15/2022]
Abstract
The current problem of increasing antibiotic resistance and the resurgence of numerous infections indicate the need for novel vaccination strategies more than ever. In vaccine development, the search for and the selection of adequate vaccine antigens is the first important step. In recent years, bacterial outer membrane proteins have become of major interest, as they are the main proteins interacting with the extracellular environment. Trimeric autotransporter adhesins (TAAs) are important virulence factors in many Gram-negative bacteria, are localised on the bacterial surface, and mediate the first adherence to host cells in the course of infection. One example is the Neisseria adhesin A (NadA), which is currently used as a subunit in a licensed vaccine against Neisseria meningitidis. Other TAAs that seem promising vaccine candidates are the Acinetobacter trimeric autotransporter (Ata), the Haemophilus influenzae adhesin (Hia), and TAAs of the genus Bartonella. Here, we review the suitability of various TAAs as vaccine candidates.
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Affiliation(s)
- Arno Thibau
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe-University, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Alexander A. Dichter
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe-University, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Diana J. Vaca
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe-University, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Adrian Goldman
- Astbury Centre for Structural Molecular Biology, School of Biomedical Sciences, University of Leeds, Leeds, UK
- Molecular and Integrative Biosciences Program, University of Helsinki, Helsinki, Finland
| | - Volkhard A. J. Kempf
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe-University, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
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Ugboko HU, Nwinyi OC, Oranusi SU, Oyewale JO. Childhood diarrhoeal diseases in developing countries. Heliyon 2020; 6:e03690. [PMID: 32322707 PMCID: PMC7160433 DOI: 10.1016/j.heliyon.2020.e03690] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/03/2019] [Accepted: 03/25/2020] [Indexed: 12/27/2022] Open
Abstract
Diarrhoeal diseases collectively constitute a serious public health challenge globally, especially as the leading cause of death in children (after respiratory diseases). Childhood diarrhoea affecting children under the age of five accounts for approximately 63% of the global burden. Accurate and timely detection of the aetiology of these diseases is very crucial; but conventional methods, apart from being laborious and time-consuming, often fail to identify difficult-to-culture pathogens. The aetiological agent of an average of up to 40% of cases of diarrhoea cannot be identified. This review gives an overview of the recent trends in the epidemiology and treatment of diarrhoea and aims at highlighting the potentials of metagenomics technique as a diagnostic method for enteric infections.
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Affiliation(s)
- Harriet U Ugboko
- Microbiology Research Unit, Department of Biological Sciences, Covenant University, Canaanland, KM 10, Idiroko Road, P.M.B, 1023, Ota, Ogun State, Nigeria
| | - Obinna C Nwinyi
- Microbiology Research Unit, Department of Biological Sciences, Covenant University, Canaanland, KM 10, Idiroko Road, P.M.B, 1023, Ota, Ogun State, Nigeria
| | - Solomon U Oranusi
- Microbiology Research Unit, Department of Biological Sciences, Covenant University, Canaanland, KM 10, Idiroko Road, P.M.B, 1023, Ota, Ogun State, Nigeria
| | - John O Oyewale
- Microbiology Research Unit, Department of Biological Sciences, Covenant University, Canaanland, KM 10, Idiroko Road, P.M.B, 1023, Ota, Ogun State, Nigeria
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Johnstone SL, Moore DP, Klugman KP, Madhi SA, Groome MJ. Epidemiology of invasive bacterial infections in pneumococcal conjugate vaccine-vaccinated and -unvaccinated children under 5 years of age in Soweto, South Africa: a cohort study from a high-HIV burden setting. Paediatr Int Child Health 2020; 40:50-57. [PMID: 31156062 DOI: 10.1080/20469047.2019.1623572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Background: There are limited data on paediatric invasive bacterial infections (IBI) and the impact of pneumococcal conjugate vaccine (PCV) on the spectrum of IBI pathogens, specifically in African countries with a high prevalence of HIV infection.Aim: To describe the epidemiology of IBI in a cohort of children <5 years of age in Soweto, South Africa.Methods: A cohort of children enrolled into a PCV9 efficacy trial conducted from 1998 until 2005 was used for secondary data analysis. Surveillance data were collected from admission wards at Chris Hani Baragwanath Academic Hospital. The incidence of IBI was calculated using person-time, stratified by age group, gender, PCV9 vaccination status and HIV infection status. Risk factors for IBI were investigated using binomial logistic regression.Results: A total of 395 cases of laboratory-confirmed IBI were identified. HIV infection and not receiving PCV9 vaccination were risk factors for IBI hospitalisation. PCV9 vaccination was associated with reductions in IBI hospitalisation (IRR 0.76, p = 0.006) solely owing to reductions in the incidence of Streptococcus pneumoniae (IRR 0.56, p < 0.001). PCV9 vaccination had no effect on the incidence of Haemophilus influenza type b or Salmonella species IBI. There was an increase in Klebsiella species IBI (IRR 3.50, p = 0.019) and a trend towards a higher incidence of Staphylococcus aureus IBI (IRR 1.90, p = 0.099) in PCV9-vaccinated children.Conclusions: PCV9 vaccination was effective in reducing the incidence of IBI hospitalisation in children through reductions in the incidence of S. pneumoniae. The results show that trends in other IBI causative pathogens (specifically S. aureus and Klebsiella species) should be monitored in the era of PCV vaccination.Abbreviations: ART, antiretroviral therapy; CI, confidence interval; Hib, Haemophilus influenza type b; HIV, human immunodeficiency virus; HIV+PCV-, HIV-infected, placebo-vaccinated group; HIV+PCV+, HIV-infected, PCV9-vaccinated group; HIV-PCV-, HIV-uninfected, placebo-vaccinated group; HIV+PCV+, HIV-infected, PCV9-vaccinated group; IBI, invasive bacterial infection; IPD, invasive pneumococcal disease; IRR, incidence rate ratio; IQR, interquartile range; OR, odds ratio; PCV, pneumococcal conjugate vaccine; PCV7, 7-valent pneumococcal conjugate vaccine; PCV9, 9-valent pneumococcal conjugate vaccine; PY, person-years; RCT, randomised control trial.
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Affiliation(s)
- Siobhan L Johnstone
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - David P Moore
- Department of Paediatrics and Child Health, Chris Hani Baragwanath Academic Hospital and University of the Witwatersrand, Johannesburg, South Africa
| | - Keith P Klugman
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Shabir A Madhi
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Michelle J Groome
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
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49
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Booster vaccination with a fractional dose of an oral cholera vaccine induces comparable vaccine-specific antibody avidity as a full dose: A randomised clinical trial. Vaccine 2020; 38:655-662. [DOI: 10.1016/j.vaccine.2019.10.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 01/06/2023]
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Kuhlmann FM, Martin J, Hazen TH, Vickers TJ, Pashos M, Okhuysen PC, Gómez-Duarte OG, Cebelinski E, Boxrud D, del Canto F, Vidal R, Qadri F, Mitreva M, Rasko DA, Fleckenstein JM. Conservation and global distribution of non-canonical antigens in Enterotoxigenic Escherichia coli. PLoS Negl Trop Dis 2019; 13:e0007825. [PMID: 31756188 PMCID: PMC6897418 DOI: 10.1371/journal.pntd.0007825] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 12/06/2019] [Accepted: 10/02/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Enterotoxigenic Escherichia coli (ETEC) cause significant diarrheal morbidity and mortality in children of resource-limited regions, warranting development of effective vaccine strategies. Genetic diversity of the ETEC pathovar has impeded development of broadly protective vaccines centered on the classical canonical antigens, the colonization factors and heat-labile toxin. Two non-canonical ETEC antigens, the EtpA adhesin, and the EatA mucinase are immunogenic in humans and protective in animal models. To foster rational vaccine design that complements existing strategies, we examined the distribution and molecular conservation of these antigens in a diverse population of ETEC isolates. METHODS Geographically diverse ETEC isolates (n = 1159) were interrogated by PCR, immunoblotting, and/or whole genome sequencing (n = 46) to examine antigen conservation. The most divergent proteins were purified and their core functions assessed in vitro. RESULTS EatA and EtpA or their coding sequences were present in 57.0% and 51.5% of the ETEC isolates overall, respectively; and were globally dispersed without significant regional differences in antigen distribution. These antigens also exhibited >93% amino acid sequence identity with even the most divergent proteins retaining the core adhesin and mucinase activity assigned to the prototype molecules. CONCLUSIONS EtpA and EatA are well-conserved molecules in the ETEC pathovar, suggesting that they serve important roles in virulence and that they could be exploited for rational vaccine design.
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Affiliation(s)
- F. Matthew Kuhlmann
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
| | - John Martin
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Tracy H. Hazen
- Department of Microbiology and Immunology and Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Tim J. Vickers
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Madeline Pashos
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Pablo C. Okhuysen
- The Department of Infectious Diseases, Infection Control and Employee Health, University of Texas M.D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Oscar G. Gómez-Duarte
- Department of Pediatrics, Division of Infectious Diseases, University at Buffalo, The State University of New York, Buffalo, New York, United States of America
| | | | - Dave Boxrud
- Minnesota Department of Health, St. Paul, Minnesota, United States of America
| | - Felipe del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Roberto Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Instituto Milenio de Inmunonología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Firdausi Qadri
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Makedonka Mitreva
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - David A. Rasko
- Department of Microbiology and Immunology and Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - James M. Fleckenstein
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Medicine Service, Veterans Affairs Medical Center, St. Louis, Missouri, United States of America
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