1
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Sheikh A, Ganguli D, Vickers TJ, Singer BB, Foulke-Abel J, Akhtar M, Khatoon N, Setu B, Basu S, Harro C, Maier N, Beatty WL, Chakraborty S, Bhuiyan TR, Qadri F, Donowitz M, Fleckenstein JM. Host-derived CEACAM-laden vesicles engage enterotoxigenic Escherichia coli for elimination and toxin neutralization. Proc Natl Acad Sci U S A 2024; 121:e2410679121. [PMID: 39264739 PMCID: PMC11420188 DOI: 10.1073/pnas.2410679121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Accepted: 08/10/2024] [Indexed: 09/14/2024] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of diarrheal illnesses annually ranging from mildly symptomatic cases to severe, life-threatening cholera-like diarrhea. Although ETEC are associated with long-term sequelae including malnutrition, the acute diarrheal illness is largely self-limited. Recent studies indicate that in addition to causing diarrhea, the ETEC heat-labile toxin (LT) modulates the expression of many genes in intestinal epithelia, including carcinoembryonic cell adhesion molecules (CEACAMs) which ETEC exploit as receptors, enabling toxin delivery. Here, however, we demonstrate that LT also enhances the expression of CEACAMs on extracellular vesicles (EV) shed by intestinal epithelia and that CEACAM-laden EV increase in abundance during human infections, mitigate pathogen-host interactions, scavenge free ETEC toxins, and accelerate ETEC clearance from the gastrointestinal tract. Collectively, these findings indicate that CEACAMs play a multifaceted role in ETEC pathogen-host interactions, transiently favoring the pathogen, but ultimately contributing to innate responses that extinguish these common infections.
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Affiliation(s)
- Alaullah Sheikh
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Debayan Ganguli
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Tim J. Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Bernhard B. Singer
- Institute of Anatomy, Medical Faculty, University of Duisburg-Essen, 45147Essen, Germany
| | - Jennifer Foulke-Abel
- Division of Gastroenterology & Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - Marjahan Akhtar
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
- Enteric and Respiratory. Infections, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka1212, Bangladesh
| | - Nazia Khatoon
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Bipul Setu
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Supratim Basu
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
| | - Clayton Harro
- Division of Global Disease Epidemiology and Control with the Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD21205
| | - Nicole Maier
- Center for Vaccine Innovation and Access, PATH, Seattle, WA98121
| | - Wandy L. Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO63110
| | - Subhra Chakraborty
- Division of Global Disease Epidemiology and Control with the Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD21205
| | - Taufiqur R. Bhuiyan
- Enteric and Respiratory. Infections, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka1212, Bangladesh
| | - Firdausi Qadri
- Enteric and Respiratory. Infections, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka1212, Bangladesh
| | - Mark Donowitz
- Division of Gastroenterology & Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - James M. Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, MO63110
- Medicine Service, Infectious Disease Section, Veterans Affairs Health Care System, Saint Louis, MO63106
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2
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Berndsen ZT, Akhtar M, Thapa M, Vickers TJ, Schmitz A, Torres JL, Baboo S, Kumar P, Khatoon N, Sheikh A, Hamrick M, Diedrich JK, Martinez-Bartolome S, Garrett PT, Yates JR, Turner JS, Laird RM, Poly F, Porter CK, Copps J, Ellebedy AH, Ward AB, Fleckenstein JM. Repeat modules and N-linked glycans define structure and antigenicity of a critical enterotoxigenic E. coli adhesin. PLoS Pathog 2024; 20:e1012241. [PMID: 39283948 PMCID: PMC11463764 DOI: 10.1371/journal.ppat.1012241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 10/09/2024] [Accepted: 08/12/2024] [Indexed: 09/25/2024] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of cases of infectious diarrhea annually, predominantly in children from low-middle income regions. Notably, in children, as well as volunteers challenged with ETEC, diarrheal severity is significantly increased in blood group A (bgA) individuals. EtpA, is a secreted glycoprotein adhesin that functions as a blood group A lectin to promote critical interactions between ETEC and blood group A glycans on intestinal epithelia for effective bacterial adhesion and toxin delivery. EtpA is highly immunogenic resulting in robust antibody responses following natural infection and experimental challenge of volunteers with ETEC. To understand how EtpA directs ETEC-blood group A interactions and stimulates adaptive immunity, we mutated EtpA, mapped its glycosylation by mass-spectrometry (MS), isolated polyclonal (pAbs) and monoclonal antibodies (mAbs) from vaccinated mice and ETEC-infected volunteers, and determined structures of antibody-EtpA complexes by cryo-electron microscopy. Both bgA and mAbs that inhibited EtpA-bgA interactions and ETEC adhesion, bound to the C-terminal repeat domain highlighting this region as crucial for ETEC pathogen-host interaction. MS analysis uncovered extensive and heterogeneous N-linked glycosylation of EtpA and cryo-EM structures revealed that mAbs directly engage these unique glycan containing epitopes. Finally, electron microscopy-based polyclonal epitope mapping revealed antibodies targeting numerous distinct epitopes on N and C-terminal domains, suggesting that EtpA vaccination generates responses against neutralizing and decoy regions of the molecule. Collectively, we anticipate that these data will inform our general understanding of pathogen-host glycan interactions and adaptive immunity relevant to rational vaccine subunit design.
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Affiliation(s)
- Zachary T. Berndsen
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California, United States of America
| | - Marjahan Akhtar
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Mahima Thapa
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, United States of America
| | - Tim J. Vickers
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Aaron Schmitz
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, United States of America
| | - Jonathan L. Torres
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California, United States of America
| | - Sabyasachi Baboo
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Pardeep Kumar
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Nazia Khatoon
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Alaullah Sheikh
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Melissa Hamrick
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
| | - Jolene K. Diedrich
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Salvador Martinez-Bartolome
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Patrick T. Garrett
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - John R. Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jackson S. Turner
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, United States of America
| | - Renee M. Laird
- Operationally Relevant Infections Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, United States of America
| | - Frédéric Poly
- Operationally Relevant Infections Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, United States of America
| | - Chad K. Porter
- Translational and Clinical Research Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, United States of America
| | - Jeffrey Copps
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California, United States of America
| | - Ali H. Ellebedy
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, United States of America
- Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, St Louis, Missouri, United States of America
- The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California, United States of America
| | - James M. Fleckenstein
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, United States of America
- Operationally Relevant Infections Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, United States of America
- Medicine Service, Infectious Diseases, Veterans Affairs Health Care System, Saint Louis, Missouri, United States of America
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3
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Long KZ, Gunanti IR, Stride C, Sanchez J, Sur D, Manna B, Ramamurthy T, Kanungo S, Nataro JP, Powell H, Roose A, Nasrin D, Sommerfelt H, Levine M, Kotloff K. Identification of Enteric Pathogen Reservoirs and Transmission Pathways Associated with Short Childhood Stature in the Kolkata Indian Site of the Global Enteric Multicenter Study. Nutrients 2024; 16:2733. [PMID: 39203869 PMCID: PMC11357064 DOI: 10.3390/nu16162733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Revised: 08/08/2024] [Accepted: 08/13/2024] [Indexed: 09/03/2024] Open
Abstract
Age-stratified path analyses modeled associations between enteric pathogen reservoirs, transmission pathways and height-for-age z-scores (HAZ) to identify determinants of childhood growth in the Kolkata, India site of the Global Enteric Multicenter Study (GEMS). Models tested direct associations of potential pathogen reservoirs with HAZ at 60-day follow-up in separate moderate and severe diarrhea (MSD) case and control cohorts or indirectly when mediated by enteric infections. In the MSD cohort, rotavirus and typical EPEC (tEPEC) infections among children 0-11 months of age and ST-ETEC infections among children 12-23 months of age were associated with lower HAZ. Handwashing after defecating and before cooking reduced impaired growth through reductions in rotavirus and tEPEC infections. Water storage increased rotavirus and ST-ETEC infection risks, resulting in increased impaired growth, but was reduced with reported child feces disposal. The GII norovirus variant was inversely associated with HAZ among children 12-59 months of age in the control cohort. Reported handwashing before the handling of children reduced GII infections and impaired growth. Boiling water and the disposal of children's feces mediated by stored water were positively associated with HAZ. The targeting of pathogen-specific reservoirs and transmission pathways may more effectively improve childhood linear growth in South Asian urban communities.
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Affiliation(s)
- Kurt Z. Long
- Epidemiology and Public Health, Swiss Tropical and Public Health Institute, 4123 Allschwil, Switzerland
- Faculty of Medicine, University of Basel, Peterplatz 1, 4003 Basel, Switzerland
- The Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, Brisbane 4101, Australia
| | - Inong R. Gunanti
- The Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, Brisbane 4101, Australia
| | - Chris Stride
- The Institute of Work Psychology, University of Sheffield, Sheffield S10 2TN, UK;
| | - Johanna Sanchez
- The Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, Brisbane 4101, Australia
| | - Dipika Sur
- ICMR—National Institute for Research in Bacterial Infections, Kolkata 700010, India
| | - Byomkesh Manna
- ICMR—National Institute for Research in Bacterial Infections, Kolkata 700010, India
| | | | - Suman Kanungo
- ICMR—National Institute for Research in Bacterial Infections, Kolkata 700010, India
| | - James P. Nataro
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
| | - Helen Powell
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Anna Roose
- Department of Medicine Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Dilruba Nasrin
- Department of Medicine Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Halvor Sommerfelt
- Centre for Intervention Science in Maternal and Child Health, Centre for International Health, University of Bergen and the Norwegian Institute of Public Health, NO-5020 Bergen, Norway
| | - Myron Levine
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Medicine Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Karen Kotloff
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Medicine Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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4
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Guitor AK, Katyukhina A, Mokomane M, Lechiile K, Goldfarb DM, Wright GD, McArthur AG, Pernica JM. Minimal Impact on the Resistome of Children in Botswana After Azithromycin Treatment for Acute Severe Diarrheal Disease. J Infect Dis 2024; 230:239-249. [PMID: 39052715 PMCID: PMC11272098 DOI: 10.1093/infdis/jiae049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 02/02/2024] Open
Abstract
BACKGROUND Macrolide antibiotics, including azithromycin, can reduce under 5 years of age mortality rates and treat various infections in children in sub-Saharan Africa. These exposures, however, can select for antibiotic-resistant bacteria in the gut microbiota. METHODS Our previous randomized controlled trial (RCT) of a rapid-test-and-treat strategy for severe acute diarrheal disease in children in Botswana included an intervention (3-day azithromycin dose) group and a control group that received supportive treatment. In this prospective matched cohort study using stools collected at baseline and 60 days after treatment from RCT participants, the collection of antibiotic resistance genes or resistome was compared between groups. RESULTS Certain macrolide resistance genes increased in prevalence by 13%-55% at 60 days, without differences in gene presence between the intervention and control groups. These genes were linked to tetracycline resistance genes and mobile genetic elements. CONCLUSIONS Azithromycin treatment for bacterial diarrhea for young children in Botswana resulted in similar effects on the gut resistome as the supportive treatment and did not provide additional selective pressure for macrolide resistance gene maintenance. The gut microbiota of these children contains diverse macrolide resistance genes that may be transferred within the gut upon repeated exposures to azithromycin or coselected by other antibiotics. CLINICAL TRIALS REGISTRATION NCT02803827.
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Affiliation(s)
- Allison K Guitor
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Anna Katyukhina
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Margaret Mokomane
- School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Gaborone, Botswana
- Botswana National Health Laboratory, Gaborone, Botswana
| | - Kwana Lechiile
- Botswana-University of Pennsylvania Partnership, Gaborone, Botswana
| | - David M Goldfarb
- Botswana-University of Pennsylvania Partnership, Gaborone, Botswana
- Department of Pathology and Laboratory Medicine, British Columbia Children's Hospital, Vancouver, British Columbia, Canada
| | - Gerard D Wright
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Andrew G McArthur
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada
| | - Jeffrey M Pernica
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada
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5
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Sheikh A, Ganguli D, Vickers TJ, Singer B, Foulke-Abel J, Akhtar M, Khatoon N, Setu B, Basu S, Harro C, Maier N, Beatty WL, Chakraborty S, Bhuiyan TR, Qadri F, Donowitz M, Fleckenstein JM. Host-derived CEACAM-laden vesicles engage enterotoxigenic E. coli for elimination and toxin neutralization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.24.604983. [PMID: 39091797 PMCID: PMC11291149 DOI: 10.1101/2024.07.24.604983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of diarrheal illnesses annually ranging from mildly symptomatic cases to severe, life-threatening cholera-like diarrhea. Although ETEC are associated with long-term sequelae including malnutrition, the acute diarrheal illness is largely self-limited. Recent studies indicate that in addition to causing diarrhea, the ETEC heat-labile toxin (LT) modulates the expression of many genes in intestinal epithelia, including carcinoembryonic cell adhesion molecules (CEACAMs) which ETEC exploit as receptors, enabling toxin delivery. Here however, we demonstrate that LT also enhances the expression of CEACAMs on extracellular vesicles (EV) shed by intestinal epithelia and that CEACAM-laden EV increase in abundance during human infections, mitigate pathogen-host interactions, scavenge free ETEC toxins, and accelerate ETEC clearance from the gastrointestinal tract. Collectively, these findings indicate that CEACAMs play a multifaceted role in ETEC pathogen-host interactions, transiently favoring the pathogen, but ultimately contributing to innate responses that extinguish these common infections.
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Affiliation(s)
- Alaullah Sheikh
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Debayan Ganguli
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Tim J. Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Bernhard Singer
- Institute of Anatomy, Medical Faculty, University of Suisberg-Essen, 45147 Essen, Germany
| | - Jennifer Foulke-Abel
- Division of Gastroenterology & Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Marjahan Akhtar
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
- International Centre for Diarrhoeal Disease Research, Bangladesh; Dhaka, Bangladesh
| | - Nazia Khatoon
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Bipul Setu
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Supratim Basu
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
| | - Clayton Harro
- Department of International Health, Division of Global Disease Epidemiology and Control, Johns Hopkins Bloomberg School of Public Health
| | | | - Wandy L. Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Subhra Chakraborty
- Department of International Health, Division of Global Disease Epidemiology and Control, Johns Hopkins Bloomberg School of Public Health
| | - Tafiqur R. Bhuiyan
- International Centre for Diarrhoeal Disease Research, Bangladesh; Dhaka, Bangladesh
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research, Bangladesh; Dhaka, Bangladesh
| | - Mark Donowitz
- Division of Gastroenterology & Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - James M. Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University in Saint Louis, School of Medicine, Saint Louis, Missouri, USA
- Medicine Service, Infectious Disease Section, Veterans Affairs Health Care System, Saint Louis, Missouri, USA
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6
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Berndsen ZT, Akhtar M, Thapa M, Vickers T, Schmitz A, Torres JL, Baboo S, Kumar P, Khatoom N, Sheikh A, Hamrick M, Diedrich JK, Martinez-Bartolome S, Garrett PT, Yates JR, Turner JS, Laird RM, Poly F, Porter CK, Copps J, Ellebedy AH, Ward AB, Fleckenstein JM. Repeat modules and N-linked glycans define structure and antigenicity of a critical enterotoxigenic E. coli adhesin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.593125. [PMID: 38766097 PMCID: PMC11100705 DOI: 10.1101/2024.05.08.593125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of cases of infectious diarrhea annually, predominantly in children from low-middle income regions. Notably, in children, as well as human volunteers challenged with ETEC, diarrheal severity is significantly increased severity in blood group A (bgA) individuals. EtpA, is a secreted glycoprotein adhesin that functions as a blood group A lectin to promote critical interactions between ETEC and blood group A glycans on intestinal epithelia for effective bacterial adhesion and toxin delivery. EtpA is highly immunogenic resulting in robust antibody responses following natural infection and experimental challenge of human volunteers with ETEC. To understand how EtpA directs ETEC-blood group A interactions and stimulates adaptive immunity, we mutated EtpA, mapped its glycosylation by mass-spectrometry (MS), isolated polyclonal (pAbs) and monoclonal antibodies (mAbs) from vaccinated mice and ETEC-infected human volunteers, and determined structures of antibody-EtpA complexes by cryo-electron microscopy. Both bgA and mAbs that inhibited EtpA-bgA interactions and ETEC adhesion, bound to the C-terminal repeat domain highlighting this region as crucial for ETEC pathogen-host interaction. MS analysis uncovered extensive and heterogeneous N-linked glycosylation of EtpA and cryo-EM structures revealed that mAbs directly engage these unique glycan containing epitopes. Finally, electron microscopy-based polyclonal epitope mapping revealed antibodies targeting numerous distinct epitopes on N and C-terminal domains, suggesting that EtpA vaccination generates responses against neutralizing and decoy regions of the molecule. Collectively, we anticipate that these data will inform our general understanding of pathogen-host glycan interactions and adaptive immunity relevant to rational vaccine subunit design.
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Affiliation(s)
- Zachary T Berndsen
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, USA
| | - Marjahan Akhtar
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Mahima Thapa
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA. Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, St Louis, MO, USA and The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, MO, USA
| | - Tim Vickers
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Aaron Schmitz
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA. Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, St Louis, MO, USA and The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, MO, USA
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, USA
| | - Sabyasachi Baboo
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Pardeep Kumar
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Nazia Khatoom
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Alaullah Sheikh
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Melissa Hamrick
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
| | - Jolene K Diedrich
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Patrick T Garrett
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Jackson S Turner
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA. Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, St Louis, MO, USA and The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, MO, USA
| | - Renee M Laird
- Operationally Relevant Infections Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, USA
| | - Frédéric Poly
- Operationally Relevant Infections Department, Naval Medical Research Command (NMRC), Silver Spring, Maryland, USA
| | - Chad K Porter
- Naval Medical Research Command (NMRC), Silver Spring, Maryland, USA
- Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Jeffrey Copps
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, USA
| | - Ali H Ellebedy
- Department of Pathology and Immunology, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA. Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, St Louis, MO, USA and The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, MO, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, USA
| | - James M Fleckenstein
- Department of Medicine, Division of Infectious Diseases, Washington University in Saint Louis, School of Medicine. Saint Louis, Missouri, USA
- Medicine Service, Infectious Diseases, Veterans Affairs Health Care System, Saint Louis Missouri, USA
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7
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Widjaja NA, Hamida A, Purnomo MT, Satjadibrata A, Sari PP, Handini LS, Novi T, Hanindita MH, Irawan R. Effect of high-calorie formula on weight, height increment, IGF-1 and TLC in growth faltering children: A quasi-experimental study. Heliyon 2024; 10:e28834. [PMID: 38623243 PMCID: PMC11016603 DOI: 10.1016/j.heliyon.2024.e28834] [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] [Received: 05/27/2023] [Revised: 03/15/2024] [Accepted: 03/26/2024] [Indexed: 04/17/2024] Open
Abstract
High-calorie formulas have been used to promote catch-up growth in undernourished children. The level of insulin-like growth factor 1 (IGF-1) is closely related to weight and nutritional intake, whereas low a total lymphocyte count (TLC) is associated with impaired immune system function in undernourished children. This study was conducted to investigate the effect of high-calorie formula as an intervention on weight, height increment, IGF-1 and TLC in children with growth faltering or undernutrition. A quasi-experimental study with pre- and post-design was conducted in the outpatient clinic of a private hospital during October 2021-July 2022 on children with growth failure and underlying infection. For 90 days, subjects were given a high-calorie formula. An enzyme-linked immunosorbent assay was then conducted to measure IGF-1, followed by a complete blood count examination. Subjects were divided into two groups based on age: Group 1 (12-24 months) and Group 2 (>24-60 months). There was a significant increment in body weight and body length/height after intervention but no significant difference between the groups. The increment of body length/height after intervention was greater in Group 1 than Group 2 (p = 0.000) and reduced the incidence of stunted/severely stunted and wasted/severely wasted children (p > 0.05). IGF-1 increased after the intervention but with no significant difference (1.42 ± 8.31 ng/ml; p = 0.144). There was a significant reduction in TLC after the intervention (1194.34 + 4400.34 cells/mm3; p = 0.002) that was reduced in Group 1 and slightly increased in Group 2 (p = 0.003). Being underweight/severely underweight increased the risk of a low TLC by 27.658-fold but this risk was reduced by 25.904-fold after nutritional intervention. High-calorie formula intervention increases body weight and body length/height, reduces the incidence of underweight, stunted and wasted children and improves IGF-1 levels.
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Affiliation(s)
- Nur Aisiyah Widjaja
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
- Child Health, Husada Utama Hospital, Surabaya, Indonesia
| | - Azizah Hamida
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
| | - Marisa Tulus Purnomo
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
| | - Azarina Satjadibrata
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
| | - Putri Permata Sari
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
| | | | - Theresia Novi
- Clinical Pathology, Husada Utama Hospital, Surabaya, Indonesia
| | - Meta Herdiana Hanindita
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
| | - Roedi Irawan
- Child Health Department, Airlangga/Dr.Soetomo General Academic Teaching Hospital, Surabaya, Indonesia
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Pavlinac PB, Platts-Mills JA, Liu J, Atlas HE, Gratz J, Operario D, Rogawski McQuade ET, Ahmed D, Ahmed T, Alam T, Ashorn P, Badji H, Bahl R, Bar-Zeev N, Chisti MJ, Cornick J, Chauhan A, De Costa A, Deb S, Dhingra U, Dube Q, Duggan CP, Freyne B, Gumbi W, Hotwani A, Kabir M, Islam O, Kabir F, Kasumba I, Kibwana U, Kotloff KL, Khan SS, Maiden V, Manji K, Mehta A, Ndeketa L, Praharaj I, Qamar FN, Sazawal S, Simon J, Singa BO, Somji S, Sow SO, Tapia MD, Tigoi C, Toure A, Walson JL, Yousafzai MT, Houpt ER. Azithromycin for Bacterial Watery Diarrhea: A Reanalysis of the AntiBiotics for Children With Severe Diarrhea (ABCD) Trial Incorporating Molecular Diagnostics. J Infect Dis 2024; 229:988-998. [PMID: 37405406 PMCID: PMC11011181 DOI: 10.1093/infdis/jiad252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 05/25/2023] [Accepted: 07/03/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Bacterial pathogens cause substantial diarrhea morbidity and mortality among children living in endemic settings, yet antimicrobial treatment is only recommended for dysentery or suspected cholera. METHODS AntiBiotics for Children with severe Diarrhea was a 7-country, placebo-controlled, double-blind efficacy trial of azithromycin in children 2-23 months of age with watery diarrhea accompanied by dehydration or malnutrition. We tested fecal samples for enteric pathogens utilizing quantitative polymerase chain reaction to identify likely and possible bacterial etiologies and employed pathogen-specific cutoffs based on genomic target quantity in previous case-control diarrhea etiology studies to identify likely and possible bacterial etiologies. RESULTS Among 6692 children, the leading likely etiologies were rotavirus (21.1%), enterotoxigenic Escherichia coli encoding heat-stable toxin (13.3%), Shigella (12.6%), and Cryptosporidium (9.6%). More than one-quarter (1894 [28.3%]) had a likely and 1153 (17.3%) a possible bacterial etiology. Day 3 diarrhea was less common in those randomized to azithromycin versus placebo among children with a likely bacterial etiology (risk difference [RD]likely, -11.6 [95% confidence interval {CI}, -15.6 to -7.6]) and possible bacterial etiology (RDpossible, -8.7 [95% CI, -13.0 to -4.4]) but not in other children (RDunlikely, -0.3% [95% CI, -2.9% to 2.3%]). A similar association was observed for 90-day hospitalization or death (RDlikely, -3.1 [95% CI, -5.3 to -1.0]; RDpossible, -2.3 [95% CI, -4.5 to -.01]; RDunlikely, -0.6 [95% CI, -1.9 to .6]). The magnitude of risk differences was similar among specific likely bacterial etiologies, including Shigella. CONCLUSIONS Acute watery diarrhea confirmed or presumed to be of bacterial etiology may benefit from azithromycin treatment. CLINICAL TRIALS REGISTRATION NCT03130114.
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Affiliation(s)
- Patricia B Pavlinac
- Department of Global Health
- Department of Epidemiology, University of Washington, Seattle, WA, USA
| | - James A Platts-Mills
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Jie Liu
- School of Public Health, Qingdao University, Qingdao, China
| | | | - Jean Gratz
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Darwin Operario
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | | | | | - Tahmeed Ahmed
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Tahmina Alam
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Per Ashorn
- Center for Child, Adolescent, and Maternal Health Research, Faculty of Medicine and Health Technology, Tampere University and Tampere University Hospital, Tampere, Finland
| | - Henry Badji
- Centre pour le Développement des Vaccines, Bamako, Mali
| | - Rajiv Bahl
- Department of Maternal, Newborn, Child, and Adolescent Health and Aging, World Health Organization, Geneva, Switzerland
| | - Naor Bar-Zeev
- International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Mohammod Jobayer Chisti
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Jen Cornick
- Clinical Research Programme, Malawi Liverpool Wellcome Trust, Blantyre, Malawi
| | | | - Ayesha De Costa
- Department of Maternal, Newborn, Child, and Adolescent Health and Aging, World Health Organization, Geneva, Switzerland
| | - Saikat Deb
- Center for Public Health Kinetics, New Delhi, India
| | - Usha Dhingra
- Center for Public Health Kinetics, New Delhi, India
| | - Queen Dube
- Department of Pediatrics, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Christopher P Duggan
- Division of Gastroenterology, Hepatology and Nutrition, Department of Nutrition, Boston Children's Hospital, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Bridget Freyne
- Clinical Research Programme, Malawi Liverpool Wellcome Trust, Blantyre, Malawi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- Department of Women and Children's Health, School of Medicine, University College Dublin, Dublin, Ireland
| | - Wilson Gumbi
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aneeta Hotwani
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Mamun Kabir
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Ohedul Islam
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Furqan Kabir
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Irene Kasumba
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Upendo Kibwana
- Department of Pediatrics and Child Health, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Shaila S Khan
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
| | - Victor Maiden
- Clinical Research Programme, Malawi Liverpool Wellcome Trust, Blantyre, Malawi
| | - Karim Manji
- Department of Pediatrics and Child Health, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Ashka Mehta
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Latif Ndeketa
- Clinical Research Programme, Malawi Liverpool Wellcome Trust, Blantyre, Malawi
| | - Ira Praharaj
- Department of Gastrointestinal Sciences, Christian Medical College, Vellore, India
| | - Farah Naz Qamar
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | | | - Jonathon Simon
- Department of Maternal, Newborn, Child, and Adolescent Health and Aging, World Health Organization, Geneva, Switzerland
| | - Benson O Singa
- Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Sarah Somji
- Department of Pediatrics and Child Health, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Samba O Sow
- Centre pour le Développement des Vaccines, Bamako, Mali
| | - Milagritos D Tapia
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Caroline Tigoi
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aliou Toure
- Centre pour le Développement des Vaccines, Bamako, Mali
| | - Judd L Walson
- Department of Global Health
- Department of Epidemiology, University of Washington, Seattle, WA, USA
- Infectious Diseases, Department of Pediatrics and Medicine, University of Washington, Seattle
| | | | - Eric R Houpt
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
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Conti V, Rossi O, Clarkson KA, Mancini F, Nakakana UN, Sarakinou E, Callegaro A, Ferruzzi P, Acquaviva A, Arora AK, Marchetti E, Necchi F, Frenck RW, Martin LB, Kaminski RW, Podda A, Micoli F. Putative correlates of protection against shigellosis assessing immunomarkers across responses to S. sonnei investigational vaccine. NPJ Vaccines 2024; 9:56. [PMID: 38459072 PMCID: PMC10923941 DOI: 10.1038/s41541-024-00822-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 01/30/2024] [Indexed: 03/10/2024] Open
Abstract
Shigella spp. are a leading bacterial cause of diarrhea. No widely licensed vaccines are available and there is no generally accepted correlate of protection. We tested a S. sonnei Generalized Modules for Membrane Antigen (GMMA)-based vaccine (1790GAHB) in a phase 2b, placebo-controlled, randomized, controlled human infection model study (NCT03527173) enrolling healthy United States adults aged 18-50 years. We report analyses evaluating immune responses to vaccination, with the aim to identify correlates of risk for shigellosis among assessed immunomarkers. We found that 1790GAHB elicited S. sonnei lipopolysaccharide specific α4β7+ immunoglobulin (Ig) G and IgA secreting B cells which are likely homing to the gut, indicating the ability to induce a mucosal in addition to a systemic response, despite parenteral delivery. We were unable to establish or confirm threshold levels that predict vaccine efficacy facilitating the evaluation of vaccine candidates. However, serum anti-lipopolysaccharide IgG and bactericidal activity were identified as potential correlates of risk for shigellosis.
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Affiliation(s)
| | - Omar Rossi
- GSK Vaccines Institute for Global Health, Siena, Italy
| | - Kristen A Clarkson
- Department of Diarrheal Disease Research, Bacterial Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Horizon Therapeutics, Deerfield, IL, USA
| | | | | | | | | | | | | | | | | | | | - Robert W Frenck
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Laura B Martin
- GSK Vaccines Institute for Global Health, Siena, Italy
- US Pharmacopeial Convention, Rockville, MD, USA
| | - Robert W Kaminski
- Department of Diarrheal Disease Research, Bacterial Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Latham BioPharm Group, Cambridge, MA, USA
| | - Audino Podda
- GSK Vaccines Institute for Global Health, Siena, Italy
- Independent Consultant, Siena, Italy
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10
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Baqar S, Bonavia A, Louis Bourgeois A, Campo JJ, Clifford A, Hanevik K, Hasso-Agopsowicz M, Hausdorff W, Kaminski R, MacLennan CA, Mantis N, Martin LB, Omore R, Pasetti M, Pavlinac P, Phalipon A, Poly F, Porter C, Ramasamy MN, Rogawski McQuade ET, Sztein MB, Walker R. The 2022 Vaccines Against Shigella and Enterotoxigenic Escherichia coli (VASE) Conference: Summary of breakout workshops. Vaccine 2024; 42:1445-1453. [PMID: 38036392 PMCID: PMC10953702 DOI: 10.1016/j.vaccine.2023.11.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/25/2023] [Accepted: 11/21/2023] [Indexed: 12/02/2023]
Abstract
The global public health nonprofit organization PATH hosted the third Vaccines Against Shigella and Enterotoxigenic Escherichia coli (VASE) Conference in Washington, DC, from November 29 to December 1, 2022. This international gathering focused on cutting-edge research related to the development of vaccines against neglected diarrheal pathogens including Shigella, enterotoxigenic Escherichia coli (ETEC), Campylobacter, and non-typhoidal Salmonella. In addition to the conference's plenary content, the agenda featured ten breakout workshops on topics of importance to the enteric vaccine field. This unique aspect of VASE Conferences allows focused groups of attendees to engage in in-depth discussions on subjects of interest to the enteric vaccine development community. In 2022, the workshops covered a range of topics. Two focused on the public health value of enteric vaccines, with one examining how to translate evidence into policy and the other on the value proposition of potential combination vaccines against bacterial enteric pathogens. Two more workshops explored new tools for the development and evaluation of vaccines, with the first on integrating antigen/antibody technologies for mucosal vaccine and immunoprophylactic development, and the second on adjuvants specifically for Shigella vaccines for children in low- and middle-income countries. Another pair of workshops covered the status of vaccines against two emerging enteric pathogens, Campylobacter and invasive non-typhoidal Salmonella. The remaining four workshops examined the assessment of vaccine impact on acute and long-term morbidity. These included discussions on the nature and severity of intestinal inflammation; cellular immunity and immunological memory in ETEC and Shigella infections; clinical and microbiologic endpoints for Shigella vaccine efficacy studies in children; and intricacies of protective immunity to enteric pathogens. This article provides a brief summary of the presentations and discussions at each workshop in order to share these sessions with the broader enteric vaccine field.
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Affiliation(s)
| | - Aurelio Bonavia
- Bill & Melinda Gates Medical Research Institute, United States
| | | | | | | | - Kurt Hanevik
- University of Bergen, Norway; Norwegian National Advisory Unit for Tropical Infectious Diseases, Medical Department, Haukeland University Hospital, Norway
| | | | - William Hausdorff
- PATH, United States; Faculty of Medicine, Université Libre de Bruxelles, Belgium
| | | | - Calman A MacLennan
- Enteric and Diarrheal Diseases, Bill & Melinda Gates Foundation, United Kingdom; The Jenner Institute, United Kingdom
| | - Nicholas Mantis
- Wadsworth Center, New York State Department of Health, United States
| | | | - Richard Omore
- Kenya Medical Research Institute Center for Global Health Research, Kenya
| | | | | | | | | | - Chad Porter
- Naval Medical Research Command, United States
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11
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Vannice K, MacLennan CA, Long J, Steele AD. Optimizing Vaccine Trials for Enteric Diseases: The Enterics for Global Health (EFGH) Shigella Surveillance Study. Open Forum Infect Dis 2024; 11:S1-S5. [PMID: 38532964 PMCID: PMC10962720 DOI: 10.1093/ofid/ofad586] [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] [Indexed: 03/28/2024] Open
Abstract
In this introductory article, we describe the rationale for the Enterics for Global Health (EFGH) Shigella surveillance study, which is largely to optimize the design and implementation of pivotal Shigella vaccine trials in the target population of infants and young children living in low- and middle-income countries. Such optimization will ideally lead to a shorter time to vaccine availability in the target population. We also provide a brief description of the articles included in the supplement.
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Affiliation(s)
- Kirsten Vannice
- Enterics, Diagnostics, Genomics & Epidemiology, The Bill & Melinda Gates Foundation, Seattle, Washington, USA
| | - Calman Alexander MacLennan
- Enterics, Diagnostics, Genomics & Epidemiology, The Bill & Melinda Gates Foundation, Seattle, Washington, USA
| | - Jessica Long
- Enterics, Diagnostics, Genomics & Epidemiology, The Bill & Melinda Gates Foundation, Seattle, Washington, USA
| | - Andrew Duncan Steele
- Enterics, Diagnostics, Genomics & Epidemiology, The Bill & Melinda Gates Foundation, Seattle, Washington, USA
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12
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Babb C, Badji H, Bhuiyan MTR, Cornick J, Qureshi S, Sonye C, Shapiama Lopez WV, Adnan M, Atlas HE, Begum K, Brennhofer SA, Ceesay BE, Ceesay AK, Cunliffe NA, Garcia Bardales PF, Haque S, Horne B, Hossain MJ, Iqbal J, Islam MT, Islam S, Khanam F, Kotloff KL, Malemia T, Manzanares Villanueva K, Million GM, Munthali V, Ochieng JB, Ogwel B, Paredes Olortegui M, Omore R, Pavlinac PB, Platts-Mills JA, Sears KT, Secka O, Tennant SM, Peñataro Yori P, Yousafzai MT, Jere KC, Kosek MN, Munga S, Ikumapayi UN, Qadri F, Qamar FN, Rogawski McQuade ET. Evaluation of Fecal Inflammatory Biomarkers to Identify Bacterial Diarrhea Episodes: Systematic Review and Protocol for the Enterics for Global Health Shigella Surveillance Study. Open Forum Infect Dis 2024; 11:S65-S75. [PMID: 38532957 PMCID: PMC10962755 DOI: 10.1093/ofid/ofad652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
Background The measurement of fecal inflammatory biomarkers among individuals presenting to care with diarrhea could improve the identification of bacterial diarrheal episodes that would benefit from antibiotic therapy. We reviewed prior literature in this area and describe our proposed methods to evaluate 4 biomarkers in the Enterics for Global Health (EFGH) Shigella surveillance study. Methods We systematically reviewed studies since 1970 from PubMed and Embase that assessed the diagnostic characteristics of inflammatory biomarkers to identify bacterial diarrhea episodes. We extracted sensitivity and specificity and summarized the evidence by biomarker and diarrhea etiology. In EFGH, we propose using commercial enzyme-linked immunosorbent assays to test for myeloperoxidase, calprotectin, lipocalin-2, and hemoglobin in stored whole stool samples collected within 24 hours of enrollment from participants in the Bangladesh, Kenya, Malawi, Pakistan, Peru, and The Gambia sites. We will develop clinical prediction scores that incorporate the inflammatory biomarkers and evaluate their ability to identify Shigella and other bacterial etiologies of diarrhea as determined by quantitative polymerase chain reaction (qPCR). Results Forty-nine studies that assessed fecal leukocytes (n = 39), red blood cells (n = 26), lactoferrin (n = 13), calprotectin (n = 8), and myeloperoxidase (n = 1) were included in the systematic review. Sensitivities were high for identifying Shigella, moderate for identifying any bacteria, and comparable across biomarkers. Specificities varied depending on the outcomes assessed. Prior studies were generally small, identified red and white blood cells by microscopy, and used insensitive gold standard diagnostics, such as conventional bacteriological culture for pathogen detection. Conclusions Our evaluation of inflammatory biomarkers to distinguish diarrhea etiologies as determined by qPCR will provide an important addition to the prior literature, which was likely biased by the limited sensitivity of the gold standard diagnostics used. We will determine whether point-of-care biomarker tests could be a viable strategy to inform treatment decision making and increase appropriate targeting of antibiotic treatment to bacterial diarrhea episodes.
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Affiliation(s)
- Courtney Babb
- Department of Epidemiology, Emory University, Atlanta, Georgia, USA
| | - Henry Badji
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Md Taufiqur Rahman Bhuiyan
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Jennifer Cornick
- Institute of Infection, Veterinary and Ecological Sciences, Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Sonia Qureshi
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Catherine Sonye
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | - Mehreen Adnan
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Hannah E Atlas
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Kehkashan Begum
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Stephanie A Brennhofer
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA
| | - Bubacarr E Ceesay
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Abdoulie K Ceesay
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Nigel A Cunliffe
- Institute of Infection, Veterinary and Ecological Sciences, Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, United Kingdom
| | | | - Shahinur Haque
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Bri’Anna Horne
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - M Jahangir Hossain
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Junaid Iqbal
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Md Taufiqul Islam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Sadia Islam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Farhana Khanam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | | | | | | | - Billy Ogwel
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | - Richard Omore
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Patricia B Pavlinac
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - James A Platts-Mills
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA
| | - Khandra T Sears
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ousman Secka
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Sharon M Tennant
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Pablo Peñataro Yori
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA
| | | | - Khuzwayo C Jere
- Institute of Infection, Veterinary and Ecological Sciences, Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Medical Laboratory Sciences, Kamuzu University of Health Sciences, School of Life Sciences and Health Professions, Blantyre, Malawi
| | - Margaret N Kosek
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, USA
| | - Stephen Munga
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Usman N Ikumapayi
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Firdausi Qadri
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Farah Naz Qamar
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
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Keita AM, Doh S, Juma J, Nasrin D, Traoré A, Onwuchekwa U, Maguire R, Haidara FC, Sow SO, Kotloff KL, Tapia MD. The Enterics for Global Health (EFGH) Shigella Surveillance Study in Mali. Open Forum Infect Dis 2024; 11:S107-S112. [PMID: 38532954 PMCID: PMC10962726 DOI: 10.1093/ofid/ofae003] [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] [Indexed: 03/28/2024] Open
Abstract
Background In 2002, the Centre pour le Développement des Vaccins du Mali (CVD-Mali) was established as a partnership between the Mali Ministry of Health and the University of Maryland, Baltimore. Since its creation, CVD-Mali has been dedicated to describing the epidemiology of infectious diseases, supporting the development of vaccines, and training a team of local researchers. CVD-Mali participated in the Global Enteric Multicenter Study from 2007 to 2010 and the Vaccine Impact on Diarrhea in Africa study from 2015 to 2018, where the importance of Shigella as an enteric pathogen was established. Methods In the Enterics for Global Health (EFGH) Shigella surveillance study, CVD-Mali will conduct Shigella surveillance at 4 health centers serving the population currently participating in a demographic surveillance system and will measure the local incidence of Shigella diarrhea and related outcomes in 6- to 35-month-old children. Antibiotic sensitivity patterns and the costs related to these cases will also be measured. Results We anticipate reporting the number of diarrhea episodes that are positive by stool culture, the antibiotic susceptibility of these isolates, and the management and outcomes of these cases. Conclusions In Mali, the EFGH study will contribute valuable information to understanding the burden of Shigella in this population. These data will inform the evaluation of vaccine candidates.
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Affiliation(s)
- Adama Mamby Keita
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Sanogo Doh
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Jane Juma
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Dilruba Nasrin
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Awa Traoré
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Uma Onwuchekwa
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Rebecca Maguire
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Fadima C Haidara
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Samba O Sow
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Milagritos D Tapia
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
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14
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Atlas HE, Conteh B, Islam MT, Jere KC, Omore R, Sanogo D, Schiaffino F, Yousafzai MT, Ahmed N, Awuor AO, Badji H, Cornick J, Feutz E, Galagan SR, Haidara FC, Horne B, Hossen MI, Hotwani A, Houpt ER, Jallow AF, Karim M, Keita AM, Keita Y, Khanam F, Liu J, Malemia T, Manneh A, McGrath CJ, Nasrin D, Ndalama M, Ochieng JB, Ogwel B, Paredes Olortegui M, Zegarra Paredes LF, Pinedo Vasquez T, Platts-Mills JA, Qudrat-E-Khuda S, Qureshi S, Hasan Rajib MN, Rogawski McQuade ET, Sultana S, Tennant SM, Tickell KD, Witte D, Peñataro Yori P, Cunliffe NA, Hossain MJ, Kosek MN, Kotloff KL, Qadri F, Qamar FN, Tapia MD, Pavlinac PB. Diarrhea Case Surveillance in the Enterics for Global Health Shigella Surveillance Study: Epidemiologic Methods. Open Forum Infect Dis 2024; 11:S6-S16. [PMID: 38532963 PMCID: PMC10962728 DOI: 10.1093/ofid/ofad664] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
Background Shigella is a leading cause of acute watery diarrhea, dysentery, and diarrhea-attributed linear growth faltering, a precursor to stunting and lifelong morbidity. Several promising Shigella vaccines are in development and field efficacy trials will require a consortium of potential vaccine trial sites with up-to-date Shigella diarrhea incidence data. Methods The Enterics for Global Health (EFGH) Shigella surveillance study will employ facility-based enrollment of diarrhea cases aged 6-35 months with 3 months of follow-up to establish incidence rates and document clinical, anthropometric, and financial consequences of Shigella diarrhea at 7 country sites (Mali, Kenya, The Gambia, Malawi, Bangladesh, Pakistan, and Peru). Over a 24-month period between 2022 and 2024, the EFGH study aims to enroll 9800 children (1400 per country site) between 6 and 35 months of age who present to local health facilities with diarrhea. Shigella species (spp.) will be identified and serotyped from rectal swabs by conventional microbiologic methods and quantitative polymerase chain reaction. Shigella spp. isolates will undergo serotyping and antimicrobial susceptibility testing. Incorporating population and healthcare utilization estimates from contemporaneous household sampling in the catchment areas of enrollment facilities, we will estimate Shigella diarrhea incidence rates. Conclusions This multicountry surveillance network will provide key incidence data needed to design Shigella vaccine trials and strengthen readiness for potential trial implementation. Data collected in EFGH will inform policy makers about the relative importance of this vaccine-preventable disease, accelerating the time to vaccine availability and uptake among children in high-burden settings.
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Affiliation(s)
- Hannah E Atlas
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Bakary Conteh
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Md Taufiqul Islam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Khuzwayo C Jere
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- Department of Medical Laboratory Sciences, Kamuzu University of Health Sciences, School of Life Sciences and Health Professions, Blantyre, Malawi
| | - Richard Omore
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Doh Sanogo
- Centre pour le Développement des Vaccins du Mali, Bamako, Mali
| | - Francesca Schiaffino
- Faculty of Veterinary Medicine, Universidad Peruana Cayetano Heredia, Lima, Peru
- Division of Infectious Diseases and International Health University of Virginia, School of Medicine, Charlottesville, Virginia, USA
| | | | - Naveed Ahmed
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Alex O Awuor
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Henry Badji
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Jennifer Cornick
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Erika Feutz
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Sean R Galagan
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | | | - Bri’Anna Horne
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Md Ismail Hossen
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Aneeta Hotwani
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Eric R Houpt
- Division of Infectious Diseases and International Health University of Virginia, School of Medicine, Charlottesville, Virginia, USA
| | - Abdoulie F Jallow
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Mehrab Karim
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | | | - Youssouf Keita
- Centre pour le Développement des Vaccins du Mali, Bamako, Mali
| | - Farhana Khanam
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Jie Liu
- School of Public Health, Qingdao University, Qingdao, China
| | | | - Alhagie Manneh
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Christine J McGrath
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Dilruba Nasrin
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | - Billy Ogwel
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | | | | | - James A Platts-Mills
- Division of Infectious Diseases and International Health University of Virginia, School of Medicine, Charlottesville, Virginia, USA
| | - Syed Qudrat-E-Khuda
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Sonia Qureshi
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Md Nazmul Hasan Rajib
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | | | - Shazia Sultana
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Sharon M Tennant
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kirkby D Tickell
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Desiree Witte
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Pablo Peñataro Yori
- Division of Infectious Diseases and International Health University of Virginia, School of Medicine, Charlottesville, Virginia, USA
| | - Nigel A Cunliffe
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - M Jahangir Hossain
- Medical Research Council Unit The Gambia, London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Margaret N Kosek
- Division of Infectious Diseases and International Health University of Virginia, School of Medicine, Charlottesville, Virginia, USA
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Firdausi Qadri
- Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Farah Naz Qamar
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Milagritos D Tapia
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Patricia B Pavlinac
- Department of Global Health, University of Washington, Seattle, Washington, USA
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15
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Shrivastava S, Agnememel AB, Ndungo E, Islam D, Liang Y, Frenck RW, Pasetti MF. Oral immunization with Shigella sonnei WRSs2 and WRSs3 vaccine strains elicits systemic and mucosal antibodies with functional anti-microbial activity. mSphere 2024; 9:e0041923. [PMID: 38132716 PMCID: PMC10826362 DOI: 10.1128/msphere.00419-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
Shigella causes bacillary dysentery and is responsible for a high burden of disease globally. Several studies have emphasized the value of functional antibody activity to understand Shigella immunity and correlates of protection. The anti-microbial function of local (mucosal) antibodies and their contribution to preventing Shigella infection remain unknown. The goal of this study was to identify the functional humoral immune effectors elicited by two Shigella sonnei live oral vaccine candidates, WRSs2 and WRSs3. Complement-dependent bactericidal [serum bactericidal antibody (SBA)/bactericidal antibody (BA)] and opsonophagocytic killing antibody (OPKA) activity were determined in sera and stool extracts as indicators of systemic and local anti-microbial immunity. High levels of SBA/BA and OPKA were detected in serum as well as in fecal extracts from volunteers who received a single dose of WRSs2 and WRSs3. Functional antibody activity peaked on days 10 and 14 post-vaccination in fecal and serum samples, respectively. Bactericidal and OPKA titers were closely associated. Peak fold rises in functional antibody titers in serum and fecal extracts were also associated. Antibody activity interrogated in IgG and IgA purified from stool fractions identified IgG as the primary driver of mucosal bactericidal and OPKA activity, with minimal functional activity of IgA alone, highlighting an underappreciated role for IgG in bacterial clearance in the mucosa. The combination of IgG and IgA in equal proportions enhanced bactericidal and OPKA titers hinting at a co-operative or synergistic action. Our findings provide insight into the functional anti-microbial capacity of vaccine-induced mucosal IgG and IgA and propose an operative local humoral effector of protective immunity.IMPORTANCEThere is an urgent need for a safe, effective, and affordable vaccine against Shigella. Understanding the immunological underpinning of Shigella infection and the make-up of protective immunity is critical to achieve the best approach to prevent illness caused by this mucosal pathogen. We measured the complement-dependent bactericidal and opsonophagocytic antibody killing in serum and stool extracts from adult volunteers vaccinated with Shigella sonnei live oral vaccine candidates WRSs2 and WRSs3. For the first time, we detected functional antibody responses in stool samples that were correlated with those in sera. Using purified stool IgA and IgG fractions, we found that functional activity was mediated by IgG, with some help from IgA. These findings provide insight into the functional anti-microbial capacity of vaccine-induced mucosal IgG and IgA and support future studies to identify potential markers of protective mucosal immunity.
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Affiliation(s)
- Shikha Shrivastava
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Alain B. Agnememel
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Esther Ndungo
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dilara Islam
- Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Yuanyuan Liang
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Robert W. Frenck
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Marcela F. Pasetti
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
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16
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Bitilinyu-Bangoh JEV, Riesebosch S, Rebel M, Chiwaya P, Verschoor SP, Voskuijl WP, Schallig HDFH. Prevalence of Cryptosporidium and Giardia infections in under-five children with diarrhoea in Blantyre, Malawi. BMC Infect Dis 2024; 24:68. [PMID: 38195415 PMCID: PMC10777657 DOI: 10.1186/s12879-024-08979-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/03/2024] [Indexed: 01/11/2024] Open
Abstract
BACKGROUND Diarrhoeal diseases are common among children in low- and middle-income countries and are major causes of morbidity and mortality. Cryptosporidium and Giardia are considered to be the main parasitic causes of diarrhoea in children. The aim of the present study was to determine the prevalence and associated factors of Cryptosporidium and Giardia infection in children under five years of age presenting at two health centres (Ndirande and Limbe) in Blantyre, Malawi. METHODS This cross-sectional study was performed from February to July 2019 and included 972 children under 5 years of age with diarrhoea. Stool samples were immediately tested after collection at enrolment with a rapid diagnostic test for Cryptosporidium and Giardia infection. Descriptive statistics were used to assess the prevalence of these protozoan parasitic infections, and differences in the basic demographic and anthroponotic variables (between children with diarrhoea and parasite infection, being either Cryptosporidium and Giardia or both versus children with diarrhoea but no RDT confirmed parasite infection) were assessed. Their association with Cryptosporidium and Giardia infection was analysed using simple logistic regressions. RESULTS Of the children recruited, 88 (9.1%) tested positive for Cryptosporidium and 184 (18.9%) for Giardia. Children with only a Giardia infection or a coinfection (of both parasites) were significantly older (mean age 24-26 months) compared to children with only a Cryptosporidium infection (mean age 13 months) or no parasitic infection (mean age 14 months). No significant differences were found with respect to gender, body temperature, stunting or wasting between the different groups of children with moderate to severe diarrhoea. Children attending the Ndirande health centre had almost two times higher odds of testing positive for both infections than those attending Limbe health centre. CONCLUSION Cryptosporidium and Giardia infections are highly prevalent in children < 5 years with moderate to severe diarrhoea attending the Limbe and Ndirande health centres in Blantyre, Malawi.
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Affiliation(s)
- Joseph E V Bitilinyu-Bangoh
- Department of Medical Microbiology and Infection Prevention, Laboratory for Experimental Parasitology, Amsterdam University Medical Centre, Amsterdam Institute for Infection and Immunity, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Department of Paediatrics and Child Health, Kamuzu University for Health Sciences, Blantyre, Malawi
- Public Health Institute of Malawi, Lilongwe, Malawi
| | - Samra Riesebosch
- Department of Medical Microbiology and Infection Prevention, Laboratory for Experimental Parasitology, Amsterdam University Medical Centre, Amsterdam Institute for Infection and Immunity, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Department Experimental Immunology, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Marije Rebel
- Department of Medical Microbiology and Infection Prevention, Laboratory for Experimental Parasitology, Amsterdam University Medical Centre, Amsterdam Institute for Infection and Immunity, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Paul Chiwaya
- Department of Paediatrics and Child Health, Kamuzu University for Health Sciences, Blantyre, Malawi
- University of Malawi, Zomba, Malawi
| | - Sjoerd P Verschoor
- Amsterdam University Medical Centre, Amsterdam Institute for Global Child Health, Emma Children's Hospital, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Training Institute Global Health and Tropical Medicine (OIGT), Utrecht, The Netherlands
| | - Wieger P Voskuijl
- Amsterdam University Medical Centre, Amsterdam Institute for Global Child Health, Emma Children's Hospital, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Amsterdam Institute for Global Health and Development, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Department of Paediatrics and Child Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Henk D F H Schallig
- Department of Medical Microbiology and Infection Prevention, Laboratory for Experimental Parasitology, Amsterdam University Medical Centre, Amsterdam Institute for Infection and Immunity, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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17
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Hausdorff WP, Anderson JD, Bourgeois AL, Clifford A, Fleming JA, Muhib F, Pecenka C, Puett C, Riddle MS, Scheele S, Bagamian KH. Reassessing potential economic value and health impact of effective Shigella vaccines. Bull World Health Organ 2024; 102:65-74. [PMID: 38164339 PMCID: PMC10753284 DOI: 10.2471/blt.23.290163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/22/2023] [Accepted: 10/20/2023] [Indexed: 01/03/2024] Open
Abstract
The gram-negative bacterium Shigella is a leading cause of diarrheal morbidity and mortality in children in low- and middle-income countries. Several promising vaccine candidates are in late stages of clinical development against this increasingly antibiotic-resistant pathogen. However, considering the increasingly crowded and costly paediatric immunization schedule, and likely advent of other important new vaccines, it is unclear whether introduction of a Shigella vaccine would represent a high priority for international agencies or health ministries in low- and middle-income countries. To determine whether there is a compelling public health value proposition for a Shigella vaccine, we used the World Health Organization's Full Value of Vaccine Assessment analytic framework and formulated five broad scientific, policy, economic and commercial-related propositions regarding the development of a Shigella vaccine. We also explored the current regulatory, clinical, policy and commercial challenges to a Shigella-containing combination vaccine development and adoption. Through a series of literature reviews, expert consultations, social science field studies and model-based analyses, we addressed each of these propositions. As described in a series of separate publications that are synthesized here, we concluded that the economic and public health value of a Shigella vaccine may be greater than previously recognized, particularly if it is found to also be effective against less severe forms of diarrheal disease and childhood stunting. The decision by pharmaceutical companies to develop a standalone vaccine or a multipathogen combination will be a key factor in determining its relative prioritization by various stakeholders in low- and middle-income countries.
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Affiliation(s)
- William P Hausdorff
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Avenue NW, Washington, D.C.20001, United States of America (USA)
| | | | - A Louis Bourgeois
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Avenue NW, Washington, D.C.20001, United States of America (USA)
| | - Allison Clifford
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Avenue NW, Washington, D.C.20001, United States of America (USA)
| | | | - Farzana Muhib
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Avenue NW, Washington, D.C.20001, United States of America (USA)
| | | | - Chloe Puett
- Stony Brook University, Stony Brook, New York, USA
| | | | - Suzanne Scheele
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Avenue NW, Washington, D.C.20001, United States of America (USA)
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18
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Mwape K, Bosomprah S, Chibesa K, Silwamba S, Luchen CC, Sukwa N, Mubanga C, Phiri B, Chibuye M, Liswaniso F, Somwe P, Chilyabanyama O, Chisenga CC, Muyoyeta M, Simuyandi M, Barnard TG, Chilengi R. Prevalence of Diarrhoeagenic Escherichia coli among Children Aged between 0-36 Months in Peri-Urban Areas of Lusaka. Microorganisms 2023; 11:2790. [PMID: 38004801 PMCID: PMC10673189 DOI: 10.3390/microorganisms11112790] [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: 09/15/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/26/2023] Open
Abstract
Diarrhoea is a major contributor to childhood morbidity and mortality in developing countries, with diarrhoeagenic Escherichia coli being among the top aetiological agents. We sought to investigate the burden and describe the diarrhoeagenic E. coli pathotypes causing diarrhoea among children in peri-urban areas of Lusaka, Zambia. This was a facility-based surveillance study conducted over an 8-month period from 2020 to 2021. Stool samples were collected from children aged 0-3 years presenting with diarrhoea at five peri-urban health facilities in Lusaka. Stool samples were tested for diarrhoeagenic E. coli using the Novodiag bacterial GE+® panel, a platform utilising real-time PCR and microarray technology to detect bacterial pathogens. Of the 590 samples tested, diarrhoeagenic E. coli were detected in 471 (76.1%). The top three pathogens were enteropathogenic E. coli 45.4% (n = 268), enteroaggregative E. coli 39.5% (n = 233), and enterotoxigenic E. coli 29.7% (n = 176). Our results revealed that 50.1% of the diarrhoeagenic E. coli positive samples comprised multiple pathotypes of varying virulence gene combinations. Our study demonstrates a high prevalence of diarrhoeagenic E. coli in childhood diarrhoea and the early exposure (<12 months) of children to enteric pathogens. This calls for the early implementation of preventive interventions for paediatric diarrhoea.
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Affiliation(s)
- Kapambwe Mwape
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Water and Health Research Center, Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa;
- Department of Basic Medical Sciences, Michael Chilufya Sata School of Medicine, Copperbelt University, Ndola P.O. Box 71191, Zambia
| | - Samuel Bosomprah
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Department of Biostatistics, School of Public Health, University of Ghana, Accra P.O. Box LG13, Ghana
| | - Kennedy Chibesa
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Next Generation Sequencing Unit and Division of Virology, Faculty of Health Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
| | - Suwilanji Silwamba
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Department of Biomedical Sciences, School of Health Sciences, University of Zambia, Lusaka P.O. Box 50110, Zambia
| | - Charlie Chaluma Luchen
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Amsterdam Institute of Infection and Immunity, Amsterdam University Medical Centers, 1105 AZ Amsterdam, The Netherlands
- Department of Global Health, Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Nsofwa Sukwa
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Cynthia Mubanga
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Division of Medical Microbiology, Department of Pathology, Stellenbosch University & National Health Laboratory Service, Tygerberg Hospital Francie van Zijl Drive, P.O. Box 241, Cape Town 8000, South Africa
| | - Bernard Phiri
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Mwelwa Chibuye
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
- Amsterdam Institute of Infection and Immunity, Amsterdam University Medical Centers, 1105 AZ Amsterdam, The Netherlands
- Department of Global Health, Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Fraser Liswaniso
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Paul Somwe
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Obvious Chilyabanyama
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Caroline Cleopatra Chisenga
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Monde Muyoyeta
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Michelo Simuyandi
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
| | - Tobias George Barnard
- Water and Health Research Center, Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa;
| | - Roma Chilengi
- Enteric Disease and Vaccine Research Unit, Center for Infectious Disease Research in Zambia, Lusaka P.O. Box 34681, Zambia; (K.M.); (S.S.); (N.S.); (M.C.); (R.C.)
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Rinanda T, Riani C, Artarini A, Sasongko L. Correlation between gut microbiota composition, enteric infections and linear growth impairment: a case-control study in childhood stunting in Pidie, Aceh, Indonesia. Gut Pathog 2023; 15:54. [PMID: 37946290 PMCID: PMC10636988 DOI: 10.1186/s13099-023-00581-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Gut microbiota is pivotal in maintaining children's health and well-being. The ingestion of enteric pathogens and dysbiosis lead to Environmental Enteric Dysfunction (EED), which is essential in stunting pathogenesis. The roles of gut microbiome and enteric infections have not been explored comprehensively in relation to childhood stunting in Indonesia. This study aimed to determine the correlation between gut microbiota composition, enteric infections, and growth biomarker, Insulin-like Growth Factor 1 (IGF-1), in stunted children from Pidie, Aceh, Indonesia. METHODS This study was a case-control study involving 42 subjects aged 24 to 59 months, comprising 21 stunted children for the case and 21 normal children for the control group. The IGF-1 serum level was quantified using ELISA. The gut microbiome profiling was conducted using 16S rDNA amplicon sequencing. The expression of enteric pathogens virulence genes was determined using quantitative PCR (qPCR) assay. The correlations of observed variables were analysed using suitable statistical analyses. RESULTS The result showed that the IGF-1 sera levels in stunted were lower than those in normal children (p ≤ 0.001). The abundance of Firmicutes (50%) was higher than Bacteroidetes (34%) in stunted children. The gut microbiome profile of stunted children showed enriched genera such as Blautia, Dorea, Collinsella, Streptococcus, Clostridium sensu stricto 13, Asteroleplasma and Anaerostipes. Meanwhile the depleted genera comprised Prevotella, Lactococcus, Butyrivibrio, Muribaculaceae, Alloprevotella, Akkermansia, Enterococcus, Terrisporobacter and Turicibacter. The abundance of water biological contaminants such as Aeromonas, Stappiaceae, and Synechococcus was also higher in stunted children compared to normal children. The virulence genes expression of Enteroaggregative Escherichia coli (aaiC), Enterotoxigenic E. coli (estA), Enteropathogenic E. coli (eaeA), Shigella/Enteroinvasive E. coli (ipaH3) and Salmonella enterica (ompC) in stunted was higher than in normal children (p ≤ 0.001), which negatively correlated to height and level of IGF-1. CONCLUSION The present study showed the distinctive gut microbiome profile of stunted and normal children from Pidie, Aceh, Indonesia. The gut microbiota of stunted children revealed dysbiosis, comprised several pro-inflammatory, metabolic abnormalities and high-fat/low-fiber diet-related taxa, and expressed virulence genes of enteric pathogens. These findings provide evidence that it is imperative to restore dysbiosis and preserve the balance of gut microbiota to support linear growth in children.
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Affiliation(s)
- Tristia Rinanda
- Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, West Java, Indonesia
- Department of Microbiology, Faculty of Medicine, Universitas Syiah Kuala, Darussalam, Banda Aceh, 23111, Aceh, Indonesia
| | - Catur Riani
- Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, West Java, Indonesia
| | - Anita Artarini
- Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, West Java, Indonesia
| | - Lucy Sasongko
- Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, West Java, Indonesia.
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20
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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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21
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Hausdorff WP, Anderson JD, Bagamian KH, Bourgeois AL, Mills M, Sawe F, Scheele S, Talaat K, Giersing BK. Vaccine value profile for Shigella. Vaccine 2023; 41 Suppl 2:S76-S94. [PMID: 37827969 DOI: 10.1016/j.vaccine.2022.12.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 10/14/2022] [Accepted: 12/16/2022] [Indexed: 10/14/2023]
Abstract
Shigella is the leading bacterial cause of diarrhoea and the second leading cause of diarrhoeal mortality among all ages. It also exhibits increasing levels of antibiotic resistance. The greatest burden is among children under five in low- and middle-income countries (LMICs). As such, a priority strategic goal of the World Health Organization (WHO) is the development of a safe, effective and affordable vaccine to reduce morbidity and mortality from Shigella-attributable dysentery and diarrhea, including long term outcomes associated with chronic inflammation and growth faltering, in children under 5 years of age in LMICs. In addition, a safe and effective Shigella vaccine is of potential interest to travellers and military both to prevent acute disease and rarer, long-term sequelae. An effective Shigella vaccine is also anticipated to reduce antibiotic use and thereby help diminish further emergence of enteric pathogens resistant to antimicrobials. The most advanced vaccine candidates are multivalent, parenteral formulations in Phase 2 and Phase 3 clinical studies. They rely on O-antigen-polysaccharide protein conjugate technologies or, alternatively, outer membrane vesicles expressing penta-acylated lipopolysaccharide that has been detoxified. Other parenteral and oral formulations, many delivering a broader array of Shigella antigens, are at earlier stages of clinical development. These formulations are being assessed in alignment with the WHO Preferred Product Characteristics, which call for a 1 to 2 dose primary immunization series given during the first 12 months of life, ideally starting at 6 months of age. This 'Vaccine Value Profile' (VVP) for Shigella is intended to provide a high-level, holistic assessment of the information and data that are currently available 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, government agencies and multi-lateral organizations. All contributors have extensive expertise on various elements of the Shigella 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)
- William P Hausdorff
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Ave NW, Washington, DC 20001, USA; Faculty of Medicine, Université de Bruxelles, Brussels 1070, Belgium.
| | - John D Anderson
- Office of Health Affairs, West Virginia University, Morgantown, WV 26505, USA; Bagamian Scientific Consulting, LLC, Gainesville, FL 32601, 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
| | - A Louis Bourgeois
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Ave NW, Washington, DC 20001, USA
| | - Melody Mills
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892 USA
| | - Frederick Sawe
- Kenya Medical Research Institute/U.S. Army Medical Research Directorate-Africa/Kenya-Henry Jackson Foundation MRI, Kericho, Kenya
| | - Suzanne Scheele
- Center for Vaccine Innovation and Access, PATH, 455 Massachusetts Ave NW, Washington, DC 20001, USA
| | - Kawsar Talaat
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Birgitte K Giersing
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization (WHO), Geneva, Switzerland
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22
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Brennhofer SA, Platts-Mills JA, Lewnard JA, Liu J, Houpt ER, Rogawski McQuade ET. Burden of diarrhea and antibiotic use among children in low-resource settings preventable by Shigella vaccination: A simulation study. PLoS Med 2023; 20:e1004271. [PMID: 37992134 PMCID: PMC10707565 DOI: 10.1371/journal.pmed.1004271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 12/08/2023] [Accepted: 11/01/2023] [Indexed: 11/24/2023] Open
Abstract
BACKGROUND Shigella is a leading cause of diarrhea and dysentery in children in low-resource settings, which is frequently treated with antibiotics. The primary goal of a Shigella vaccine would be to reduce mortality and morbidity associated with Shigella diarrhea. However, ancillary benefits could include reducing antibiotic use and antibiotic exposures for bystander pathogens carried at the time of treatment, specifically for fluoroquinolones and macrolides (F/M), which are the recommended drug classes to treat dysentery. The aim of the study was to quantify the reduction in Shigella attributable diarrhea, all diarrhea, and antibiotic use in the first 2 years of life that could be prevented by a Shigella vaccine. METHODS AND FINDINGS We used data from the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study, a birth cohort study that followed 1,715 children with twice weekly surveillance for enteric infections, illnesses, and antibiotic use for the first 2 years of life from November 2009 to February 2014 at 8 sites. We estimated the impact of 2 one-dose (6 or 9 months) and 3 two-dose (6 and 9 months, 9 and 12 months, and 12 and 15 months) Shigella vaccines on diarrheal episodes, overall antibiotic use, and F/M use. Further, we considered additional protection through indirect and boosting effects. We used Monte Carlo simulations to estimate the absolute and relative reductions in the incidence of diarrhea and antibiotic use comparing each vaccination scenario to no vaccination. We analyzed 9,392 diarrhea episodes and 15,697 antibiotic courses among 1,715 children in the MAL-ED birth cohort study. There were 273.8 diarrhea episodes, 30.6 shigellosis episodes, and 457.6 antibiotic courses per 100 child-years. A Shigella vaccine with a mean vaccine efficacy of 60% against severe disease given at 9 and 12 months prevented 10.6 (95% CI [9.5, 11.5]) Shigella diarrhea episodes of any severity per 100 child-years (relative 34.5% reduction), 3.0 (95% CI [2.5, 3.5]) F/M courses for Shigella treatment per 100 child-years (relative 35.8% reduction), and 5.6 (95% CI [5.0, 6.3]) antibiotic courses of any drug class for Shigella treatment per 100 child-years (relative 34.5% reduction). This translated to a relative 3.8% reduction in all diarrhea, a relative 2.8% reduction in all F/M courses, a relative 3.1% reduction in F/M exposures to bystander pathogens, and a relative 0.9% reduction in all antibiotic courses. These results reflect Shigella incidence and antibiotic use patterns at the 8 MAL-ED sites and may not be generalizable to all low-resource settings. CONCLUSIONS Our simulation results suggest that a Shigella vaccine meeting WHO targets for efficacy could prevent about a third of Shigella diarrhea episodes, antibiotic use to treat shigellosis, and bystander exposures due to shigellosis treatment. However, the reductions in overall diarrhea episodes and antibiotic use are expected to be modest (<5%).
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Affiliation(s)
- Stephanie A. Brennhofer
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virginia, United States of America
| | - James A. Platts-Mills
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virginia, United States of America
| | - Joseph A. Lewnard
- Division of Epidemiology, School of Public Health, University of California, Berkeley, California, United States of America
| | - Jie Liu
- School of Public Health, Qingdao University, Qingdao, Shandong, People’s Republic of China
| | - Eric R. Houpt
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, Virginia, United States of America
| | - Elizabeth T. Rogawski McQuade
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
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Khan SM, Bajwa MR, Lahar RY, Witola WH. Combination of inhibitors for two glycolytic enzymes portrays high synergistic efficacy against Cryptosporidium parvum. Antimicrob Agents Chemother 2023; 67:e0056923. [PMID: 37655889 PMCID: PMC10583678 DOI: 10.1128/aac.00569-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 06/22/2023] [Indexed: 09/02/2023] Open
Abstract
Cryptosporidium is an intracellular protozoan parasite that causes serious enteric disease in humans and in a wide range of animals worldwide. Despite its high prevalence, no effective therapeutic drugs are available against life-threatening cryptosporidiosis in at-risk populations including malnourished children, immunocompromised patients, and neonatal calves. Thus, new efficacious drugs are urgently needed to treat all susceptible populations with cryptosporidiosis. Unlike other apicomplexans, Cryptosporidium parvum lacks the tricarboxylic acid cycle and the oxidative phosphorylation steps, making it solely dependent on glycolysis for metabolic energy production. We have previously reported that individual inhibitors of two unique glycolytic enzymes, the plant-like pyruvate kinase (CpPyK) and the bacterial-type lactate dehydrogenase (CpLDH), are effective against C. parvum, both in vitro and in vivo. Herein, we have derived combinations of CpPyK and CpLDH inhibitors with strong synergistic effects against the growth and survival of C. parvum, both in vitro and in an infection mouse model. In infected immunocompromised mice, compound combinations of NSC303244 + NSC158011 and NSC252172 + NSC158011 depicted enhanced efficacy against C. parvum reproduction and ameliorated intestinal lesions of cryptosporidiosis at doses fourfold lower than the total effective doses of individual compounds. Importantly, unlike individual compounds, NSC303244 + NSC158011 combination was effective in clearing the infection completely without relapse in immunocompromised mice. Collectively, our study has unveiled compound combinations that simultaneously block two essential catalytic steps for metabolic energy production in C. parvum to achieve improved efficacy against the parasite. These combinations are, therefore, lead compounds for the development of a new generation of efficacious anti-cryptosporidial drugs.
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Affiliation(s)
- Shahbaz M. Khan
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Muhammad Rashid Bajwa
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Rachael Y. Lahar
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - William H. Witola
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
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Das R, Palit P, Haque MA, Levine MM, Kotloff KL, Nasrin D, Hossain MJ, Sur D, Ahmed T, Breiman RF, Freeman MC, Faruque ASG. Symptomatic and asymptomatic enteric protozoan parasitic infection and their association with subsequent growth parameters in under five children in South Asia and sub-Saharan Africa. PLoS Negl Trop Dis 2023; 17:e0011687. [PMID: 37816031 PMCID: PMC10588856 DOI: 10.1371/journal.pntd.0011687] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 10/20/2023] [Accepted: 09/27/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Entamoeba histolytica, Giardia, and Cryptosporidium are common intestinal protozoan parasites that contribute to a high burden of childhood morbidity and mortality. Our study quantified the association between intestinal protozoan parasites and child anthropometric outcomes among children under-5. METHODS We analyzed data from 7,800 children enrolled in the Global Enteric Multicenter Study (GEMS) across seven study sites that were positive for intestinal protozoan parasites between December 2007 and March 2011. Parasites were assessed using stool immunoassays (ELISA). We applied multiple linear regression to test the association between any or concurrent parasite and child anthropometric outcomes: length/height-for-age (HAZ), weight-for-age (WAZ), and weight-for-length/height (WHZ) z-score after 60 days of enrollment. Models were stratified by diarrheal symptoms, driven by the study design, and adjusted for potential covariates. FINDINGS During the follow-up at day 60 after enrollment, child anthropometric outcomes, among the asymptomatic children showed, negative associations between Giardia with HAZ [β: -0.13; 95% CI: -0.17, -0.09; p<0.001] and WAZ [β -0.07; 95% CI: -0.11, -0.04; p<0.001], but not WHZ [β: -0.02; 95% CI:-0.06, 0.02; p = 0.36]; Cryptosporidium with WAZ [β: -0.15; 95% CI: -0.22, -0.09; p<0.001] and WHZ [β: -0.18; 95%CI: -0.25, -0.12; p<0.001], but not with HAZ [β: -0.03; 95% CI: -0.09, 0.04; p = 0.40]. For symptomatic children, no associations were found between Giardia and anthropometry; negative associations were found between Cryptosporidium with HAZ [β: -0.17; 95% CI: -0.23, -0.11; p<0.001], WAZ [β: -0.25; 95% CI: -0.31, -0.19; p<0.001] and WHZ [β: -0.23; 95% CI: -0.30, -0.17; p<0.001]. Among the asymptomatic 24-59 months children, Giardia had a negative association with HAZ [β: -0.09; 95% CI: -0.15, -0.04; p = 0.001]. No significant associations were found between E. histolytica with child growth. CONCLUSIONS While some studies have found that Giardia is not associated with (or protective against) acute diarrhea, our findings suggest that it is associated with growth shortfall. This observation underscores the need for preventive strategies targeting enteric protozoan parasites among young children, to reduce the burden of childhood malnutrition.
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Affiliation(s)
- Rina Das
- Nutrition Research Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Parag Palit
- Nutrition Research Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
- University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Md. Ahshanul Haque
- Nutrition Research Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Myron M. Levine
- University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Karen L. Kotloff
- University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Dilruba Nasrin
- University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - M. Jahangir Hossain
- Medical Research Council Unit, London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Dipika Sur
- National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India
| | - Tahmeed Ahmed
- Nutrition Research Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
- James P. Grant School of Public Health, BRAC University, Dhaka, Bangladesh
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
| | - Robert F. Breiman
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Matthew C. Freeman
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - A. S. G. Faruque
- Nutrition Research Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
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Hollifield IE, Motyka NI, Fernando KA, Bitoun JP. Heat-Labile Enterotoxin Decreases Macrophage Phagocytosis of Enterotoxigenic Escherichia coli. Microorganisms 2023; 11:2121. [PMID: 37630681 PMCID: PMC10459231 DOI: 10.3390/microorganisms11082121] [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: 06/30/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Enterotoxigenic E. coli (ETEC) are endemic in low-resource settings and cause robust secretory diarrheal disease in children less than five years of age. ETEC cause secretory diarrhea by producing the heat-stable (ST) and/or heat-labile (LT) enterotoxins. Recent studies have shown that ETEC can be carried asymptomatically in children and adults, but how ETEC subvert mucosal immunity to establish intestinal residency remains unclear. Macrophages are innate immune cells that can be exploited by enteric pathogens to evade mucosal immunity, so we interrogated the ability of ETEC and other E. coli pathovars to survive within macrophages. Using gentamicin protection assays, we show that ETEC H10407 is phagocytosed more readily than other ETEC and non-ETEC isolates. Furthermore, we demonstrate that ETEC H10407, at high bacterial burdens, causes nitrite accumulation in macrophages, which is indicative of a proinflammatory macrophage nitric oxide killing response. However, at low bacterial burdens, ETEC H10407 remains viable within macrophages for an extended period without nitrite accumulation. We demonstrate that LT, but not ST, intoxication decreases the number of ETEC phagocytosed by macrophages. Furthermore, we now show that macrophages exposed simultaneously to LPS and LT produce IL-33, which is a cytokine implicated in promoting macrophage alternative activation, iron recycling, and intestinal repair. Lastly, iron restriction using deferoxamine induces IL-33 receptor (IL-33R) expression and allows ETEC to escape macrophages. Altogether, these data demonstrate that LT provides ETEC with the ability to decrease the perceived ETEC burden and suppresses the initiation of inflammation. Furthermore, these data suggest that host IL-33/IL-33R signaling may augment pathways that promote iron restriction to facilitate ETEC escape from macrophages. These data could help explain novel mechanisms of immune subversion that may contribute to asymptomatic ETEC carriage.
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Affiliation(s)
| | | | | | - Jacob P. Bitoun
- Department of Microbiology and Immunology, Tulane University School of Medicine, 1430 Tulane Avenue, #8638, New Orleans, LA 70112, USA; (I.E.H.); (N.I.M.); (K.A.F.)
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26
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Anderson JD, Bagamian KH, Pecenka CJ, Muhib F, Puett CA, Hausdorff WP, Scheele S. Potential impact and cost-effectiveness of Shigella vaccination in 102 low-income and middle-income countries in children aged 5 years or younger: a modelling study. Lancet Glob Health 2023; 11:e880-e891. [PMID: 37202023 PMCID: PMC10206199 DOI: 10.1016/s2214-109x(23)00192-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 03/31/2023] [Accepted: 04/04/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND Vaccine impact and cost-effectiveness models have mostly focused on acute burden. Shigella-attributable moderate-to-severe diarrhoea has been shown to be associated with childhood linear growth faltering. Evidence also links less severe diarrhoea to linear growth faltering. As Shigella vaccines are in late stages of clinical development, we aimed to estimate the potential impact and cost-effectiveness of vaccination against Shigella burden that includes stunting and the acute burden attributable to less severe diarrhoea and moderate-to-severe diarrhoea. METHODS We used a simulation model to estimate Shigella burden and potential vaccination in children aged 5 years or younger from 102 low-income to middle-income countries from 2025 to 2044. Our model included stunting associated with Shigella-related moderate-to-severe diarrhoea and less severe diarrhoea and we explored vaccination impact on health and economic outcomes. FINDINGS We estimate 109 million (95% uncertainty interval [UI] 39-204) Shigella-attributable stunting cases and 1·4 million (0·8-2·1) deaths in unvaccinated children over 20 years. We project that Shigella vaccination could avert 43 million (13-92) stunting cases and 590 000 (297 000-983 000) deaths over 20 years. The overall mean incremental cost-effectiveness ratio (ICER) was US$849 (95% uncertainty interval 423-1575; median $790 [IQR 635-1005]) per disability-adjusted life-year averted. Vaccination was most cost-effective in the WHO African region and in low-income countries. Including the burden of Shigella-related less severe diarrhoea improved mean ICERs by 47-48% for these groups and substantially improved ICERs for other regions. INTERPRETATION Our model suggests that Shigella vaccination would be a cost-effective intervention, with a substantial impact in specific countries and regions. Other regions could potentially benefit upon the inclusion of the burden of Shigella-related stunting and less severe diarrhoea in the analysis. FUNDING Bill & Melinda Gates Foundation and Wellcome Trust.
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Affiliation(s)
- John D Anderson
- Bagamian Scientific Consulting, Gainesville, FL, USA; Health Affairs Institute, West Virginia University, Morgantown, WV, USA.
| | - Karoun H Bagamian
- Bagamian Scientific Consulting, Gainesville, FL, USA; Department of Environmental and Global Health, University of Florida, Gainesville, FL, USA
| | - Clint J Pecenka
- Center for Vaccine Innovation and Access, PATH, Seattle, WA, USA
| | - Farzana Muhib
- Center for Vaccine Innovation and Access, PATH, Washington, DC, USA
| | - Chloe A Puett
- Stony Brook University, Department of Family, Population & Preventative Medicine, Program in Public Health, Stony Brook, NY, USA
| | - William P Hausdorff
- Center for Vaccine Innovation and Access, PATH, Washington, DC, USA; Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Suzanne Scheele
- Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
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Puett C, Anderson JD, Bagamian KH, Muhib F, Scheele S, Hausdorff WP, Pecenka C. Projecting the long-term economic benefits of reducing Shigella-attributable linear growth faltering with a potential vaccine: a modelling study. Lancet Glob Health 2023; 11:e892-e902. [PMID: 37202024 PMCID: PMC10205973 DOI: 10.1016/s2214-109x(23)00050-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 12/25/2022] [Accepted: 01/17/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND Linear growth is an important outcome of child development with implications for economic productivity. Enteric infections, particularly Shigella, have been linked to linear growth faltering (LGF). However, benefits from potential reductions in LGF are rarely included in economic analyses of enteric infections. We aimed to quantify the economic benefits of vaccination related to reduced Shigella-attributable disease and associated LGF compared with the net costs of a vaccine programme. METHODS In this benefit-cost analysis, we modelled productivity benefits in 102 low-income and middle-income countries that had recent stunting estimates available, at least one Shigella-attributable death annually, and available economic data, particularly on gross national income and growth rate projections. We modelled benefits strictly related to linear growth improvements and no other benefits associated with reducing diarrhoeal burden. The effect size in each country was calculated as shifts in height-for-age Z score (HAZ), representing population average changes for preventing Shigella-attributable less-severe diarrhoea and moderate-to-severe diarrhoea separately for children younger than 5 years. Benefits data were calculated per country and combined with estimated net costs of the vaccine programme in the form of benefit-cost ratios (BCRs); BCRs above parity, or $1 in benefits per $1 in costs (with a 10% margin representing borderline results: 1·10:1), were considered cost-beneficial. Countries were aggregated for analysis by WHO region, World Bank income category, and eligibility for support from Gavi, the Vaccine Alliance. FINDINGS In the base-case scenario, all regions exhibited cost-beneficial results, with the South-East Asia region and Gavi-eligible countries exhibiting the highest BCRs (21·67 for the South-East Asia region and 14·45 for Gavi-eligible countries), and the Eastern Mediterranean region yielding the lowest BCRs (2·90). All regions exhibited cost-beneficial results from vaccination, except in more conservative scenarios (eg, those assuming early retirement ages and higher discount rates). Our findings were sensitive to assumed returns for increased height, assumptions about vaccine efficacy against linear growth detriments, the anticipated shift in HAZ, and discount rate. Incorporating the productivity benefits of LGF reduction into existing cost-effectiveness estimates resulted in longer-term cost-savings in nearly all regions. INTERPRETATION LGF is a secondary outcome of Shigella infection and reduction in LGF is not often quantified as a health or economic benefit of vaccination. However, even under conservative assumptions, a Shigella vaccine only moderately effective against LGF could pay for itself from productivity gains alone in some regions. We recommend that LGF be considered in future models assessing the economic and health impacts of interventions preventing enteric infections. Further research is needed on vaccine efficacy against LGF to inform such models. FUNDING Bill & Melinda Gates Foundation, Wellcome Trust.
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Affiliation(s)
- Chloe Puett
- Department of Family, Population & Preventive Medicine, Program in Public Health, Health Sciences Center, Stony Brook University, Stony Brook, NY, USA.
| | | | - Karoun H Bagamian
- Bagamian Scientific Consulting, Gainesville, FL, USA; Department of Environmental and Global Health, University of Florida, Gainesville, FL, USA
| | | | | | - William P Hausdorff
- PATH, Washington, DC, USA; Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
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Riddle MS, Louis Bourgeois A, Clifford A, Jeon S, Giersing BK, Jit M, Tufet Bayona M, Ovitt J, Hausdorff WP. Challenges and opportunities in developing a Shigella-containing combination vaccine for children in low- and middle-income countries: Report of an expert convening. Vaccine 2023; 41:2634-2644. [PMID: 36932030 DOI: 10.1016/j.vaccine.2023.03.003] [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: 11/12/2022] [Revised: 02/28/2023] [Accepted: 03/02/2023] [Indexed: 03/17/2023]
Abstract
The gram-negative bacterium Shigella is an enteric pathogen responsible for significant morbidity and mortality due primarily to severe diarrhea and dysentery, mainly among children younger than five years of age living in low- and middle-income countries (LMICs). Long considered a priority target for vaccine development, recent scientific advances have led to a number of promising Shigella vaccine candidates now entering advanced stages of clinical testing. Yet, there is no guarantee that even a highly efficacious Shigella vaccine will be recommended, prioritized, purchased, and widely adopted-especially if it requires additional doses in the immunization schedule and/or visits within the immunization program. This uncertainty is due to a variety of factors, including continuing declines in Shigella-specific and overall diarrheal disease mortality rates, the increasing complexity and cost of infant immunization programs in LMICs, and the recent availability of other high-priority vaccines. Since combining a Shigella vaccine with an existing infant vaccine would conceivably increase its attractiveness, there is a need to systematically consider the challenges determining the public health value, clinical development, manufacturing, licensure, policy recommendations, and financing for a Shigella-containing combination vaccine. The international non-governmental health organization PATH convened an independent panel of 34 subject matter experts across academic, industry, philanthropic, and global health sectors to discuss hypothetical combinations of a notional parenteral Shigella vaccine with three existing vaccines in order to begin exploring the challenges associated with their development. The resulting insights and recommendations from this meeting contribute to PATH's broader effort to evaluate the public health value of potential Shigella vaccines. They may also help guide future combination vaccine development efforts more broadly.
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Affiliation(s)
- Mark S Riddle
- University of Nevada, Reno School of Medicine, Reno, NV 89557, USA.
| | - A Louis Bourgeois
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001, USA
| | - Allison Clifford
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001, USA
| | - Suhi Jeon
- EuBiologics Co., Ltd. 8F, Seongdo Building, 207, Dosan-daero, Sinsa-dong, Gangnam-gu, Seoul, Republic of Korea
| | - Birgitte K Giersing
- World Health Organization, Immunization, Vaccines and Biologicals Department, 1211 Geneva, Switzerland
| | - Mark Jit
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Marta Tufet Bayona
- Gavi, The Vaccine Alliance, Chemin du Pommier 40, 1218 Le Grand-Saconnex, Geneva, Switzerland
| | - Jared Ovitt
- University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - William P Hausdorff
- PATH, Center for Vaccine Innovation and Access, 455 Massachusetts Ave NW, Washington, DC 20001, USA; Université Libre de Bruxelles, Faculty of Medicine, Brussels, Belgium
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Libby TE, Delawalla MLM, Al-Shimari F, MacLennan CA, Vannice KS, Pavlinac PB. Consequences of Shigella infection in young children: a systematic review. Int J Infect Dis 2023; 129:78-95. [PMID: 36736579 PMCID: PMC10017352 DOI: 10.1016/j.ijid.2023.01.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 01/07/2023] [Accepted: 01/24/2023] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVES We conducted a systematic review of the longitudinal consequences of Shigella infection in children to inform the value proposition for an effective vaccine. METHODS We searched PubMed and Embase for studies published from January 01, 1980 to December 12, 2022 and conducted in low- and middle-income countries that included longitudinal follow-up after Shigella detection among children aged <5 years, irrespective of language. We collected data on all outcomes subsequent to Shigella detection, except mortality. RESULTS Of 2627 papers identified, 52 met inclusion criteria. The median sample size of children aged <5 years was 66 (range 5-2172). Data were collected in 20 countries; 56% (n = 29) of the publications included Bangladesh. The most common outcomes related to diarrhea (n = 20), linear growth (n = 14), and the mean total cost of a Shigella episode (n = 4; range: $ 6.22-31.10). Among children with Shigella diarrhea, 2.9-61.1% developed persistent diarrhea (≥14 days); the persistence was significantly more likely among children who were malnourished, had bloody stool, or had multidrug-resistant Shigella. Cumulative Shigella infections over the first 2 years of life contributed to the greatest loss in length-for-age z-score. CONCLUSION We identified evidence that Shigella is associated with persistent diarrhea, linear growth faltering, and economic impact to the family.
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Affiliation(s)
- Tanya E Libby
- Department of Epidemiology, University of Washington, Seattle, Washington, USA.
| | | | - Fatima Al-Shimari
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | | | | | - Patricia B Pavlinac
- Department of Global Health, University of Washington, Seattle, Washington, USA
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Oriá RB, Freitas RS, Roque CR, Nascimento JCR, Silva AP, Malva JO, Guerrant RL, Vitek MP. ApoE Mimetic Peptides to Improve the Vicious Cycle of Malnutrition and Enteric Infections by Targeting the Intestinal and Blood-Brain Barriers. Pharmaceutics 2023; 15:pharmaceutics15041086. [PMID: 37111572 PMCID: PMC10141726 DOI: 10.3390/pharmaceutics15041086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/21/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Apolipoprotein E (apoE) mimetic peptides are engineered fragments of the native apoE protein’s LDL-receptor binding site that improve the outcomes following a brain injury and intestinal inflammation in a variety of models. The vicious cycle of enteric infections and malnutrition is closely related to environmental-driven enteric dysfunction early in life, and such chronic inflammatory conditions may blunt the developmental trajectories of children with worrisome and often irreversible physical and cognitive faltering. This window of time for microbiota maturation and brain plasticity is key to protecting cognitive domains, brain health, and achieving optimal/full developmental potential. This review summarizes the potential role of promising apoE mimetic peptides to improve the function of the gut-brain axis, including targeting the blood-brain barrier in children afflicted with malnutrition and enteric infections.
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Affiliation(s)
- Reinaldo B. Oriá
- Laboratory of Tissue Healing, Ontogeny and Nutrition, Department of Morphology, School of Medicine, Institute of Biomedicine, Federal University of Ceara, Fortaleza 60430-270, Brazil
- Correspondence: ; Tel.: +55-85-3366-8239
| | - Raul S. Freitas
- Laboratory of Tissue Healing, Ontogeny and Nutrition, Department of Morphology, School of Medicine, Institute of Biomedicine, Federal University of Ceara, Fortaleza 60430-270, Brazil
| | - Cássia R. Roque
- Laboratory of Tissue Healing, Ontogeny and Nutrition, Department of Morphology, School of Medicine, Institute of Biomedicine, Federal University of Ceara, Fortaleza 60430-270, Brazil
| | - José Carlos R. Nascimento
- Laboratory of Tissue Healing, Ontogeny and Nutrition, Department of Morphology, School of Medicine, Institute of Biomedicine, Federal University of Ceara, Fortaleza 60430-270, Brazil
- Institute of Health Sciences, Medicine, University of International Integration of Afro-Brazilian Lusofonia, Redenção 62790-970, Brazil
| | - Ana Paula Silva
- Institute of Pharmacology and Experimental Therapeutics and Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine and Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal
| | - João O. Malva
- Institute of Pharmacology and Experimental Therapeutics and Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine and Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal
| | - Richard L. Guerrant
- Division of Infectious Diseases and International Health, Department of Medicine, School of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - Michael P. Vitek
- Division of Neurology, Duke University Medical Center, Durham, NC 27710, USA
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Badr HS, Colston JM, Nguyen NLH, Chen YT, Burnett E, Ali SA, Rayamajhi A, Satter SM, Van Trang N, Eibach D, Krumkamp R, May J, Adegnika AA, Manouana GP, Kremsner PG, Chilengi R, Hatyoka L, Debes AK, Ateudjieu J, Faruque ASG, Hossain MJ, Kanungo S, Kotloff KL, Mandomando I, Nisar MI, Omore R, Sow SO, Zaidi AKM, Lambrecht N, Adu B, Page N, Platts-Mills JA, Mavacala Freitas C, Pelkonen T, Ashorn P, Maleta K, Ahmed T, Bessong P, Bhutta ZA, Mason C, Mduma E, Olortegui MP, Peñataro Yori P, Lima AAM, Kang G, Humphrey J, Ntozini R, Prendergast AJ, Okada K, Wongboot W, Langeland N, Moyo SJ, Gaensbauer J, Melgar M, Freeman M, Chard AN, Thongpaseuth V, Houpt E, Zaitchik BF, Kosek MN. Spatiotemporal variation in risk of Shigella infection in childhood: a global risk mapping and prediction model using individual participant data. Lancet Glob Health 2023; 11:e373-e384. [PMID: 36796984 PMCID: PMC10020138 DOI: 10.1016/s2214-109x(22)00549-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/18/2022] [Accepted: 12/14/2022] [Indexed: 02/16/2023]
Abstract
BACKGROUND Diarrhoeal disease is a leading cause of childhood illness and death globally, and Shigella is a major aetiological contributor for which a vaccine might soon be available. The primary objective of this study was to model the spatiotemporal variation in paediatric Shigella infection and map its predicted prevalence across low-income and middle-income countries (LMICs). METHODS Individual participant data for Shigella positivity in stool samples were sourced from multiple LMIC-based studies of children aged 59 months or younger. Covariates included household-level and participant-level factors ascertained by study investigators and environmental and hydrometeorological variables extracted from various data products at georeferenced child locations. Multivariate models were fitted and prevalence predictions obtained by syndrome and age stratum. FINDINGS 20 studies from 23 countries (including locations in Central America and South America, sub-Saharan Africa, and south and southeast Asia) contributed 66 563 sample results. Age, symptom status, and study design contributed most to model performance followed by temperature, wind speed, relative humidity, and soil moisture. Probability of Shigella infection exceeded 20% when both precipitation and soil moisture were above average and had a 43% peak in uncomplicated diarrhoea cases at 33°C temperatures, above which it decreased. Compared with unimproved sanitation, improved sanitation decreased the odds of Shigella infection by 19% (odds ratio [OR]=0·81 [95% CI 0·76-0·86]) and open defecation decreased them by 18% (OR=0·82 [0·76-0·88]). INTERPRETATION The distribution of Shigella is more sensitive to climatological factors, such as temperature, than previously recognised. Conditions in much of sub-Saharan Africa are particularly propitious for Shigella transmission, although hotspots also occur in South America and Central America, the Ganges-Brahmaputra Delta, and the island of New Guinea. These findings can inform prioritisation of populations for future vaccine trials and campaigns. FUNDING NASA, National Institutes of Health-The National Institute of Allergy and Infectious Diseases, and Bill & Melinda Gates Foundation.
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Affiliation(s)
- Hamada S Badr
- Department of Earth and Planetary Sciences, Johns Hopkins Krieger School of Arts and Sciences, Baltimore, MA, USA
| | - Josh M Colston
- Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | | | - Yen Ting Chen
- Department of Emergency Medicine, Chi-Mei Medical Center, Tainan, Taiwan
| | - Eleanor Burnett
- Division of Viral Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Syed Asad Ali
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Ajit Rayamajhi
- Department of Pediatrics, National Academy of Medical Sciences, Kanti Children's Hospital, Kathmandu, Nepal
| | - Syed M Satter
- Programme for Emerging Infections, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | | | - Daniel Eibach
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine (BNITM), Hamburg, Germany
| | - Ralf Krumkamp
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine (BNITM), Hamburg, Germany
| | - Jürgen May
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine (BNITM), Hamburg, Germany
| | - Ayola Akim Adegnika
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Tübingen, Germany
| | | | | | - Roma Chilengi
- Centre for Infectious Disease Research in Zambia, Lusaka, Zambia
| | - Luiza Hatyoka
- Enteric diseases and Vaccines Unit, Centre for Infectious Disease Research in Zambia, Lusaka, Zambia
| | - Amanda K Debes
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jerome Ateudjieu
- Faculty of Medicine and Pharmaceutical Sciences, University of Dschang, Dschang, Cameroon; Department of Health Research, M A SANTE (Meileur Acces aux Soins en Santé), Yaoundé, Cameroon; Division of Health Operations Research, Cameroon Ministry of Public Health, Yaoundé, Cameroon
| | - Abu S G Faruque
- Centre for Nutrition & Food Security, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - M Jahangir Hossain
- Medical Research Council Unit, The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Suman Kanungo
- National Institute of Cholera and Enteric Diseases, Kolkota, India
| | - Karen L Kotloff
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - M Imran Nisar
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Richard Omore
- Kenya Medical Research Institute, Center for Global Health Research, Kisumu, Nyanza, Kenya
| | - Samba O Sow
- Centre pour le Développement des Vaccins, Mali, Bamako, Mali
| | - Anita K M Zaidi
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Nathalie Lambrecht
- Institute of Public Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany; Research Department 2, Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, Potsdam, Germany
| | - Bright Adu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Nicola Page
- Centre for Enteric Diseases, National Institute for Communicable Diseases, Pretoria, South Africa
| | - James A Platts-Mills
- Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | | | - Tuula Pelkonen
- New Children's Hospital, Pediatric Research Center and Helsinki University Hospital, Helsinki, Finland
| | - Per Ashorn
- Centre for Child, Adolescent, and Maternal Health Research, Faculty of Medicine and Health Technology, Tampere University and Tampere University Hospital, Tampere, Finland
| | - Kenneth Maleta
- College of Medicine, University of Malawi, Blantyre, Malawi
| | - Tahmeed Ahmed
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Pascal Bessong
- HIV/AIDS & Global Health Research Programme, University of Venda, Thohoyandou, Limpopo, South Africa
| | - Zulfiqar A Bhutta
- Center of Excellence in Women and Child Health, Aga Khan University, Karachi, Pakistan
| | - Carl Mason
- Department of Enteric Diseases, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | | | | | - Pablo Peñataro Yori
- Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Aldo A M Lima
- Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - Gagandeep Kang
- Department of Gastrointestinal Sciences, Christian Medical College, Vellore, India
| | - Jean Humphrey
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Robert Ntozini
- Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | | | - Kazuhisa Okada
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Warawan Wongboot
- Department of Medical Sciences, National Institute of Health, Nonthaburi, Thailand
| | - Nina Langeland
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Sabrina J Moyo
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - James Gaensbauer
- Center for Global Health, Department of Epidemiology, Colorado School of Public Health, Aurora, CO, USA
| | - Mario Melgar
- Pediatric Infectious Diseases, Hospital Roosevelt, Guatemala City, Guatemala
| | - Matthew Freeman
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, 30322, GA, USA
| | - Anna N Chard
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, 30322, GA, USA
| | - Vonethalom Thongpaseuth
- Laboratory and Treatment Unit, Center for Malariology, Parasitology, and Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Eric Houpt
- Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Benjamin F Zaitchik
- Department of Earth and Planetary Sciences, Johns Hopkins Krieger School of Arts and Sciences, Baltimore, MA, USA.
| | - Margaret N Kosek
- Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA
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Toward a Shigella Vaccine: Opportunities and Challenges to Fight an Antimicrobial-Resistant Pathogen. Int J Mol Sci 2023; 24:ijms24054649. [PMID: 36902092 PMCID: PMC10003550 DOI: 10.3390/ijms24054649] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/04/2023] Open
Abstract
Shigellosis causes more than 200,000 deaths worldwide and most of this burden falls on Low- and Middle-Income Countries (LMICs), with a particular incidence in children under 5 years of age. In the last decades, Shigella has become even more worrisome because of the onset of antimicrobial-resistant strains (AMR). Indeed, the WHO has listed Shigella as one of the priority pathogens for the development of new interventions. To date, there are no broadly available vaccines against shigellosis, but several candidates are being evaluated in preclinical and clinical studies, bringing to light very important data and information. With the aim to facilitate the understanding of the state-of-the-art of Shigella vaccine development, here we report what is known about Shigella epidemiology and pathogenesis with a focus on virulence factors and potential antigens for vaccine development. We discuss immunity after natural infection and immunization. In addition, we highlight the main characteristics of the different technologies that have been applied for the development of a vaccine with broad protection against Shigella.
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Sheikh A, Fleckenstein JM. Interactions of pathogenic Escherichia coli with CEACAMs. Front Immunol 2023; 14:1120331. [PMID: 36865539 PMCID: PMC9971599 DOI: 10.3389/fimmu.2023.1120331] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/30/2023] [Indexed: 02/16/2023] Open
Abstract
The pathogenic Escherichia coli can be parsed into specific variants (pathovars) depending on their phenotypic behavior and/or expression of specific virulence factors. These pathogens are built around chromosomally-encoded core attributes and through acquisition of specific virulence genes that direct their interaction with the host. Engagement of E. coli pathovars with CEACAMs is determined both by core elements common to all E. coli as well as extrachromosomally-encoded pathovar-specific virulence traits, which target amino terminal immunoglobulin variable-like (IgV) regions of CEACAMs. Emerging data suggests that engagement of CEACAMs does not unilaterally benefit the pathogen and that these interactions may also provide an avenue for pathogen elimination.
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Affiliation(s)
- Alaullah Sheikh
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - James M. Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States
- Infectious Diseases, Medicine Service, Veterans Affairs Saint Louis Health Care System, Saint Louis, MO, United States
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Heat-Stable Enterotoxin Secretions Assessed via ICP-MS Reveal Iron-Mediated Regulation of Virulence in CFA/I- and CS6-Expressing ETEC Isolates. Cells 2023; 12:cells12040567. [PMID: 36831233 PMCID: PMC9954033 DOI: 10.3390/cells12040567] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/11/2023] [Accepted: 02/03/2023] [Indexed: 02/12/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) are a significant cause of childhood diarrhea in low-resource settings. ETEC are defined by the production of heat-stable enterotoxin (ST) and/or heat-labile enterotoxin (LT), which alter intracellular cyclic nucleotide signaling and cause the secretion of water and electrolytes into the intestinal lumen. ETEC take cues from chemicals (e.g., glycans, bile salts, and solutes) that may be liberated following enterotoxin activity to recognize entrance into the host. ETEC then alter the expression of surface adhesins called colonization factors (CFs) to attach to the intestinal epithelium, proliferate, and cause disease. Here, we used an in vivo model of oral ST intoxication to determine its impact on luminal ion concentrations via ICP-MS. We also used functional assays, including Western blots, qPCR, and toxin activity assays, to assess the impact of luminal ion flux on CF and toxin expression. Finally, we assessed ETEC strains with CFs CFA/I or CS6 in a streptomycin mouse model of ETEC colonization. ST causes rapid and significant increases in luminal chloride but significant decreases in luminal magnesium and iron. We confirmed that increased sodium chloride suppresses CFA/I production in ETEC H10407 but does not affect CS6 production in ETEC 214-4. CFA/I production in ETEC H10407 is increased when magnesium becomes limiting, although it does not affect CS6 production in ETEC 214-4. Iron restriction via deferoxamine induces CFA/I expression in ETEC H10407 but not CS6 expression in ETEC 214-4. We demonstrate that ST production is suppressed via iron restriction in H10407, 214-4, and over 50 other ETEC clinical isolates. Lastly, we demonstrate that the iron restriction of mice using oral deferoxamine pre-treatment extends the duration of ETEC H10407 (CFA/I+) fecal shedding while accelerating ETEC 214-4 (CS6+) fecal shedding. Combined, these data suggest that enterotoxins modulate luminal ion flux to influence ETEC virulence including toxin and CF production.
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Caravedo MA, White AC. Treatment of cryptosporidiosis: nitazoxanide yes, but we can do better. Expert Rev Anti Infect Ther 2023; 21:167-173. [PMID: 36533398 DOI: 10.1080/14787210.2023.2160704] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Cryptosporidiosis was initially recognized as an important cause of diarrhea in AIDS patients. It has been underdiagnosed in other populations. Recent studies have highlighted the importance of Cryptosporidium as a cause of diarrhea and malnutrition in young children in resource-poor countries and an emerging pathogen in organ-transplant recipients. AREAS COVERED Nitazoxanide is FDA approved for treatment of cryptosporidiosis in immunocompetent people. However, it is less effective in HIV and transplant patients and malnourished children. In transplant recipients, there is emerging data on antiparasitic combinations for cryptosporidiosis, including combinations of nitazoxanide, azithromycin, and in one case rifaximin. High-throughput phenotypic screens have identified some potential treatments. Among them, clofazimine was no better than placebo in a trial in AIDS patients. There have also been efforts to develop drug versus specific parasite targets. However, in part due to safety issues, none of these compounds have advanced into clinical trials. EXPERT OPINION Development of new and more efficacious therapies for cryptosporidium is imperative. Current approve therapy is far from optimal and lacks efficacy in high-risk populations, such as, patients living with HIV. Additionally, there is limited data on patients with other types of immunosuppression (Transplanted, autoimmune conditions, etc).
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Affiliation(s)
- Maria A Caravedo
- Infectious Disease Division Department of Internal Medicine University of Texas Medical Branch, Galveston, Texas, USA
| | - A Clinton White
- Infectious Disease Division Department of Internal Medicine University of Texas Medical Branch, Galveston, Texas, USA
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Khan SM, Witola WH. Past, current, and potential treatments for cryptosporidiosis in humans and farm animals: A comprehensive review. Front Cell Infect Microbiol 2023; 13:1115522. [PMID: 36761902 PMCID: PMC9902888 DOI: 10.3389/fcimb.2023.1115522] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 01/09/2023] [Indexed: 01/25/2023] Open
Abstract
The intracellular protozoan parasite of the genus Cryptosporidium is among the leading causes of waterborne diarrheal disease outbreaks throughout the world. The parasite is transmitted by ingestion of infective oocysts that are highly stable in the environment and resistant to almost all conventional disinfection methods and water treatments. Control of the parasite infection is exceedingly difficult due to the excretion of large numbers of oocysts in the feces of infected individuals that contaminate the environment and serve as a source of infection for susceptible hosts including humans and animals. Drug development against the parasite is challenging owing to its limited genetic tractability, absence of conventional drug targets, unique intracellular location within the host, and the paucity of robust cell culture platforms for continuous parasite propagation. Despite the high prevalence of the parasite, the only US Food and Drug Administration (FDA)-approved treatment of Cryptosporidium infections is nitazoxanide, which has shown moderate efficacy in immunocompetent patients. More importantly, no effective therapeutic drugs are available for treating severe, potentially life-threatening cryptosporidiosis in immunodeficient patients, young children, and neonatal livestock. Thus, safe, inexpensive, and efficacious drugs are urgently required to reduce the ever-increasing global cryptosporidiosis burden especially in low-resource countries. Several compounds have been tested for both in vitro and in vivo efficacy against the disease. However, to date, only a few experimental compounds have been subjected to clinical trials in natural hosts, and among those none have proven efficacious. This review provides an overview of the past and present anti-Cryptosporidium pharmacotherapy in humans and agricultural animals. Herein, we also highlight the progress made in the field over the last few years and discuss the different strategies employed for discovery and development of effective prospective treatments for cryptosporidiosis.
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Ahmed SM, Brintz BJ, Pavlinac PB, Shahrin L, Huq S, Levine AC, Nelson EJ, Platts-Mills JA, Kotloff KL, Leung DT. Derivation and external validation of clinical prediction rules identifying children at risk of linear growth faltering. eLife 2023; 12:78491. [PMID: 36607225 PMCID: PMC9833824 DOI: 10.7554/elife.78491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 12/29/2022] [Indexed: 01/07/2023] Open
Abstract
Background Nearly 150 million children under-5 years of age were stunted in 2020. We aimed to develop a clinical prediction rule (CPR) to identify children likely to experience additional stunting following acute diarrhea, to enable targeted approaches to prevent this irreversible outcome. Methods We used clinical and demographic data from the Global Enteric Multicenter Study (GEMS) to build predictive models of linear growth faltering (decrease of ≥0.5 or ≥1.0 in height-for-age z-score [HAZ] at 60-day follow-up) in children ≤59 months presenting with moderate-to-severe diarrhea, and community controls, in Africa and Asia. We screened variables using random forests, and assessed predictive performance with random forest regression and logistic regression using fivefold cross-validation. We used the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study to (1) re-derive, and (2) externally validate our GEMS-derived CPR. Results Of 7639 children in GEMS, 1744 (22.8%) experienced severe growth faltering (≥0.5 decrease in HAZ). In MAL-ED, we analyzed 5683 diarrhea episodes from 1322 children, of which 961 (16.9%) episodes experienced severe growth faltering. Top predictors of growth faltering in GEMS were: age, HAZ at enrollment, respiratory rate, temperature, and number of people living in the household. The maximum area under the curve (AUC) was 0.75 (95% confidence interval [CI]: 0.75, 0.75) with 20 predictors, while 2 predictors yielded an AUC of 0.71 (95% CI: 0.71, 0.72). Results were similar in the MAL-ED re-derivation. A 2-variable CPR derived from children 0-23 months in GEMS had an AUC = 0.63 (95% CI: 0.62, 0.65), and AUC = 0.68 (95% CI: 0.63, 0.74) when externally validated in MAL-ED. Conclusions Our findings indicate that use of prediction rules could help identify children at risk of poor outcomes after an episode of diarrheal illness. They may also be generalizable to all children, regardless of diarrhea status. Funding This work was supported by the National Institutes of Health under Ruth L. Kirschstein National Research Service Award NIH T32AI055434 and by the National Institute of Allergy and Infectious Diseases (R01AI135114).
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Affiliation(s)
- Sharia M Ahmed
- Division of Infectious Diseases, University of Utah School of MedicineSalt lake CityUnited States
| | - Ben J Brintz
- Division of Epidemiology, University of Utah School of MedicineSalt Lake CityUnited States
| | - Patricia B Pavlinac
- Department of Global Health, Global Center for Integrated Health of Women, Adolescents and Children (Global WACh), University of WashingtonSeattleUnited States
| | - Lubaba Shahrin
- International Centre for Diarrhoeal Disease ResearchDhakaBangladesh
| | - Sayeeda Huq
- International Centre for Diarrhoeal Disease ResearchDhakaBangladesh
| | - Adam C Levine
- Department of Emergency Medicine, Warren Alpert Medical School of Brown UniversityProvidenceUnited States
| | - Eric J Nelson
- Department of Pediatrics and Environmental and Global Health, Emerging Pathogens Institute, University of FloridaGainesvilleUnited States
| | - James A Platts-Mills
- Division of Infectious Diseases and International Health, University of VirginiaCharlottesvilleUnited States
| | - Karen L Kotloff
- Department of Pediatrics, Center for Vaccine Development, University of Maryland School of MedicineBaltimoreUnited States
| | - Daniel T Leung
- Division of Infectious Diseases, University of Utah School of MedicineSalt lake CityUnited States,Division of Microbiology & Immunology, University of Utah School of MedicineSalt Lake CityUnited States
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Sheikh A, Tumala B, Vickers TJ, Martin JC, Rosa BA, Sabui S, Basu S, Simoes RD, Mitreva M, Storer C, Tyksen E, Head RD, Beatty W, Said HM, Fleckenstein JM. Enterotoxigenic Escherichia coli heat-labile toxin drives enteropathic changes in small intestinal epithelia. Nat Commun 2022; 13:6886. [PMID: 36371425 PMCID: PMC9653437 DOI: 10.1038/s41467-022-34687-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 11/01/2022] [Indexed: 11/14/2022] Open
Abstract
Enterotoxigenic E. coli (ETEC) produce heat-labile (LT) and/or heat-stable (ST) enterotoxins, and commonly cause diarrhea in resource-poor regions. ETEC have been linked repeatedly to sequelae in children including enteropathy, malnutrition, and growth impairment. Although cellular actions of ETEC enterotoxins leading to diarrhea are well-established, their contributions to sequelae remain unclear. LT increases cellular cAMP to activate protein kinase A (PKA) that phosphorylates ion channels driving intestinal export of salt and water resulting in diarrhea. As PKA also modulates transcription of many genes, we interrogated transcriptional profiles of LT-treated intestinal epithelia. Here we show that LT significantly alters intestinal epithelial gene expression directing biogenesis of the brush border, the major site for nutrient absorption, suppresses transcription factors HNF4 and SMAD4 critical to enterocyte differentiation, and profoundly disrupts microvillus architecture and essential nutrient transport. In addition, ETEC-challenged neonatal mice exhibit substantial brush border derangement that is prevented by maternal vaccination with LT. Finally, mice repeatedly challenged with toxigenic ETEC exhibit impaired growth recapitulating the multiplicative impact of recurring ETEC infections in children. These findings highlight impacts of ETEC enterotoxins beyond acute diarrheal illness and may inform approaches to prevent major sequelae of these common infections including malnutrition that impact millions of children.
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Affiliation(s)
- Alaullah Sheikh
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Brunda Tumala
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Tim J Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - John C Martin
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Subrata Sabui
- Departments of Medicine and Physiology/Biophysics, School of Medicine, University of California-Irvine, Irvine, CA, 92697, USA
- Department of Research, VA Medical Center, Long Beach, CA, 90822, USA
| | - Supratim Basu
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Rita D Simoes
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Chad Storer
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Erik Tyksen
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Richard D Head
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Wandy Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Hamid M Said
- Departments of Medicine and Physiology/Biophysics, School of Medicine, University of California-Irvine, Irvine, CA, 92697, USA
- Department of Research, VA Medical Center, Long Beach, CA, 90822, USA
| | - James M Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Infectious Diseases, Medicine Service, Veterans Affairs Saint Louis Health Care System, Saint Louis, MO, 63106, USA.
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MacLennan CA, Steele AD. Frontiers in Shigella Vaccine Development. Vaccines (Basel) 2022; 10:vaccines10091536. [PMID: 36146614 PMCID: PMC9503259 DOI: 10.3390/vaccines10091536] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 08/11/2022] [Indexed: 01/15/2023] Open
Abstract
In recent years, there has been a resurgence of interest in the development of vaccines against Shigella driven by the growing awareness of the impact of this pathogen on global health [...]
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Could a Shigella vaccine impact long-term health outcomes?: Summary report of an expert meeting to inform a Shigella vaccine public health value proposition, March 24 and 29, 2021. Vaccine X 2022; 12:100218. [PMID: 36237199 PMCID: PMC9551074 DOI: 10.1016/j.jvacx.2022.100218] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/03/2022] [Accepted: 09/19/2022] [Indexed: 12/03/2022] Open
Abstract
Shigellosis is a leading cause of diarrhea and dysentery in young children from low to middle-income countries and adults experiencing traveler’s diarrhea worldwide. In addition to acute illness, infection by Shigella bacteria is associated with stunted growth among children, which has been linked to detrimental long-term health, developmental, and economic outcomes. On March 24 and 29, 2021, PATH convened an expert panel to discuss the potential impact of Shigella vaccines on these long-term outcomes. Based on current empirical evidence, this discussion focused on whether Shigella vaccines could potentially alleviate the long-term burden associated with Shigella infections. Also, the experts provided recommendations about how to best model the burden, health and vaccine impact, and economic consequences of Shigella infections. This international multidisciplinary panel included 13 scientists, physicians, and economists from multiple relevant specialties. According to the panel, while the relationship between Shigella infections and childhood growth deficits is complex, this relationship likely exists. Vaccine probe studies are the crucial next step to determine whether vaccination could ameliorate Shigella infection-related long-term impacts. Infants should be vaccinated during their first year of life to maximize their protection from severe acute health outcomes and ideally reduce stunting risk and subsequent negative long-term developmental and health impacts. With vaccine schedule crowding, targeted or combination vaccination approaches would likely increase vaccine uptake in high-burden areas. Shigella impact and economic assessment models should include a wider range of linear growth outcomes. Also, these models should produce a spectrum of results—ones addressing immediate benefits for usual health care decision-makers and others that include broader health impacts, providing a more comprehensive picture of vaccination benefits. While many of the underlying mechanisms of this relationship need better characterization, the remaining gaps can be best addressed by collecting data post-vaccine introduction or through large trials.
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MacLennan CA, Grow S, Ma LF, Steele AD. The Shigella Vaccines Pipeline. Vaccines (Basel) 2022; 10:vaccines10091376. [PMID: 36146457 PMCID: PMC9504713 DOI: 10.3390/vaccines10091376] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/06/2022] [Accepted: 08/10/2022] [Indexed: 11/22/2022] Open
Abstract
Shigella is the leading cause of global diarrheal deaths that currently lacks a licensed vaccine. Shigellosis drives antimicrobial resistance and leads to economic impact through linear growth faltering. Today, there is a robust pipeline of vaccines in clinical development which are broadly divided into parenteral glycoconjugate vaccines, consisting of O-antigen conjugated to carrier proteins, and oral live attenuated vaccines, which incorporate targeted genetic mutations seeking to optimize the balance between reactogenicity, immunogenicity and ultimately protection. Proof of efficacy has previously been shown with both approaches but for various reasons no vaccine has been licensed to date. In this report, we outline the requirements for a Shigella vaccine and describe the current pipeline in the context of the many candidates that have previously failed or been abandoned. The report refers to papers from individual vaccine developers in this special supplement of Vaccines which is focused on Shigella vaccines. Once readouts of safety and immunogenicity from current trials of lead candidate vaccines among the target population of young children in low- and middle-income countries are available, the likely time to licensure of a first Shigella vaccine will become clearer.
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Imdad A, Chen FF, François M, Tanner-Smith E, Smith A, Tsistinas OJ, Das JK, Bhutta ZA. Protocol for a systematic review on routine use of antibiotics for infants less than 6 months of age with growth failure/faltering. BMJ Open 2022; 12:e057241. [PMID: 35772832 PMCID: PMC9247651 DOI: 10.1136/bmjopen-2021-057241] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 06/13/2022] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION Antibiotics have been used as an adjunct in treating children with severe acute malnutrition 6-59 months of age; however, the data for infants less than 6 months are scarce. The WHO recently started guideline development for preventing and treating wasting, including growth failure/faltering in infants less than 6 months. This systematic review commissioned by WHO aims to synthesise evidence from current literature on the effectiveness of antibiotics for infants less than 6 months of age with growth failure/faltering. METHODS AND ANALYSIS We will conduct a systematic review and meta-analysis for studies that assessed the effect of antibiotics in the treatment of infants with growth faltering. We will search multiple electronic databases. We will include randomised control trials and non-randomised studies with a control arm. The study population is infants less than 6 months of age with growth failure. The intervention group will be infants who received no antibiotics or antibiotics other than recommended in 2013 guidelines by WHO to treat severe acute malnutrition in children. The comparison group will be infants who received antibiotics according to the 2013 guideline by WHO. We will consider the following outcomes: mortality, clinical deterioration, antimicrobial resistance, recovery from comorbidity, adverse events, markers of intestinal inflammation, markers of systemic inflammation, hospital-acquired infections, non-response. We will use the meta-analysis to pool the studies where applicable. We will use the Grading of Recommendations Assessment, Development, and Evaluation approach to reporting the overall evidence quality for an outcome. ETHICS AND DISSEMINATION This is a systematic review and will not involve contact with a human subject. The findings of this review will be published in a peer-review journal and will guide the WHO's recommendation for the use of antibiotics in infants less than 6 months of age with growth failure. PROSPERO REGISTRATION NUMBER CRD42021277073.
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Affiliation(s)
- Aamer Imdad
- Division of Pediatric Gastroenterology, Department of Pediatrics, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Fanny F Chen
- College of Medicine, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Melissa François
- College of Medicine, SUNY Upstate Medical University, Syracuse, New York, USA
| | | | - Abigail Smith
- Health Science Library, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Olivia J Tsistinas
- Health Science Library, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Jai K Das
- Division of Women and Child Health, Aga Khan University, Karachi, Pakistan
| | - Zulfiqar Ahmed Bhutta
- Division of Women and Child Health, The Aga Khan University, Karachi, Sindh, Pakistan
- SickKids, Toronto, Ontario, Canada
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Johansen ØH, Abdissa A, Zangenberg M, Mekonnen Z, Eshetu B, Sharew B, Moyo S, Sommerfelt H, Langeland N, Robertson LJ, Hanevik K. A comparison of risk factors for cryptosporidiosis and non-cryptosporidiosis diarrhoea: A case-case-control study in Ethiopian children. PLoS Negl Trop Dis 2022; 16:e0010508. [PMID: 35666717 PMCID: PMC9203008 DOI: 10.1371/journal.pntd.0010508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 06/16/2022] [Accepted: 05/17/2022] [Indexed: 11/18/2022] Open
Abstract
Background
Cryptosporidiosis is a major cause of diarrhoea in young children in low-and-middle-income countries. New interventions should be informed by evidence pertaining to risk factors and their relative importance. Inconsistencies in the literature may to some extent be explained by choice of methodology, furthermore, most previous risk factor studies compared cryptosporidiosis cases to diarrhoea cases of other aetiologies rather than with controls without diarrhoea.
Methodology/Principal findings
We investigated a broad set of factors in under-2-year-olds presenting with diarrhoea to a hospital and a health center in southwestern Ethiopia. We applied quantitative cut-offs to distinguish between cryptosporidiosis and incidental Cryptosporidium infection or carriage, a hierarchical causal framework to minimize confounding and overadjustment, and a case-case-control design, to describe risk factors for both cryptosporidiosis and non-cryptosporidiosis diarrhoea. Moderate and severe acute malnutrition were strongly associated with both cryptosporidiosis and non-cryptosporidiosis diarrhoea. Previous healthcare attendance and low maternal education were only associated with cryptosporidiosis, whereas unsafe child stool disposal, prematurity and early cessation of exclusive breastfeeding were significantly associated with non-cryptosporidiosis diarrhoea only. By estimation of population attributable fractions, socioeconomic factors—specifically low maternal education—and public tap water use, were apparently more important risk factors for cryptosporidiosis than for non-cryptosporidiosis diarrhoea.
Conclusions/Significance
Nutritional management of moderate acute malnutrition may be an effective intervention against cryptosporidiosis, particularly if combined with targeted therapy for cryptosporidiosis which, again, may mitigate nutritional insult. Focused caregiver education in healthcare settings and follow-up of children with acute malnutrition may prevent or improve outcomes of future episodes of cryptosporidiosis.
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Affiliation(s)
- Øystein Haarklau Johansen
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Microbiology, Vestfold Hospital Trust, Tønsberg, Norway
- * E-mail:
| | - Alemseged Abdissa
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Mike Zangenberg
- Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Department of Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
| | - Zeleke Mekonnen
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Beza Eshetu
- Department of Paediatrics, Jimma Medical Centre, Jimma University, Jimma, Ethiopia
| | - Bizuwarek Sharew
- School of Medical Laboratory Sciences, Jimma University, Jimma, Ethiopia
| | - Sabrina Moyo
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Halvor Sommerfelt
- Centre for Intervention Science in Maternal and Child Health, Centre for International Health, University of Bergen, Bergen, Norway
- Cluster for Global Health, Division for Health Services, Norwegian Institute of Public Health, Oslo, Norway
| | - Nina Langeland
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Lucy J. Robertson
- Parasitology, Department of Paraclinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Kurt Hanevik
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway
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Pernica JM, Arscott-Mills T, Steenhoff AP, Mokomane M, Moorad B, Bapabi M, Lechiile K, Mangwegape O, Batisani B, Mawoko N, Muthoga C, Vanniyasingam T, Ewusie J, Lowe A, Bonsu JM, Gezmu AM, Smieja M, Mazhani L, Stordal K, Thabane L, Kelly MS, Goldfarb DM. Optimising the management of childhood acute diarrhoeal disease using a rapid test-and- treat strategy and/or Lactobacillus reuteri DSM 17938: a multicentre, randomised, controlled, factorial trial in Botswana. BMJ Glob Health 2022; 7:bmjgh-2021-007826. [PMID: 35418412 PMCID: PMC9014020 DOI: 10.1136/bmjgh-2021-007826] [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] [Received: 10/27/2021] [Accepted: 03/14/2022] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION The study aim was to determine if rapid enteric diagnostics followed by the provision of targeted antibiotic therapy ('test-and-treat') and/or Lactobacillus reuteri DSM 17938 would improve outcomes in children hospitalised in Botswana with acute gastroenteritis. METHODS This was a multicentre, randomised, factorial, controlled, trial. Children aged 2-60 months admitted for acute non-bloody diarrhoea to four hospitals in southern Botswana were eligible. Participants were assigned to treatment groups by web-based block randomisation. Test-and-treat results were not blinded, but participants and research staff were blinded to L. reuteri/placebo assignment; this was dosed as 1×108 cfu/mL by mouth daily and continued for 60 days. The primary outcome was 60-day age-standardised height (HAZ) adjusted for baseline HAZ. All analyses were by intention to treat. The trial was registered at Clinicaltrials.gov. RESULTS Recruitment began on 12 June 2016 and continued until 24 October 2018. There were 66 participants randomised to the test-and-treat plus L. reuteri group, 68 randomised to the test-and-treat plus placebo group, 69 to the standard care plus L. reuteri group and 69 to the standard care plus placebo group. There was no demonstrable impact of the test-and-treat intervention (mean increase of 0.01 SD, 95% CI -0.14 to 0.16 SD) or the L. reuteri intervention (mean decrease of 0.07 SD, 95% CI -0.22 to 0.08 SD) on adjusted HAZ at 60 days. CONCLUSIONS In children hospitalised for acute gastroenteritis in Botswana, neither a test-and-treat algorithm targeting enteropathogens, nor a 60-day course of L. reuteri DSM 17938, were found to markedly impact linear growth or other important outcomes. We cannot exclude the possibility that test-and-treat will improve the care of children with significant enteropathogens (such as Shigella) in their stool. TRIAL REGISTRATION NUMBER NCT02803827.
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Affiliation(s)
- Jeffrey M Pernica
- Department of Pediatrics, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada .,Department of Health Research Methods, Evidence, and Impact, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada
| | - Tonya Arscott-Mills
- Botswana-UPenn Partnership, Gaborone, Botswana.,The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Global Health Center, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Andrew P Steenhoff
- Global Health Center, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Margaret Mokomane
- Department of Microbiology, University of Botswana, Gaborone, South-East District, Botswana
| | | | | | | | | | | | | | - Charles Muthoga
- Botswana-UPenn Partnership, Gaborone, Botswana.,Botswana-Harvard AIDS Institute Partnership, Gaborone, Gaborone, Botswana
| | - Thuvaraha Vanniyasingam
- Department of Health Research Methods, Evidence, and Impact, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada
| | - Joycelyne Ewusie
- Department of Health Research Methods, Evidence, and Impact, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada.,The Research Institute-Biostatistics Unit, St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Amy Lowe
- Department of Global Health, McMaster University, Hamilton, Ontario, Canada
| | - Janice M Bonsu
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Alemayehu M Gezmu
- Department of Pediatrics and Adolescent Health, University of Botswana, Gaborone, Botswana
| | - Marek Smieja
- Department of Health Research Methods, Evidence, and Impact, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada
| | - Loeto Mazhani
- Department of Pediatrics and Adolescent Health, University of Botswana, Gaborone, Botswana
| | - Ketil Stordal
- Pediatric Research Institute, University of Oslo Faculty of Medicine, Oslo, Norway
| | - Lehana Thabane
- Department of Pediatrics, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada.,Department of Health Research Methods, Evidence, and Impact, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada.,The Research Institute-Biostatistics Unit, St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada.,University of Johannesburg Faculty of Health Sciences, Johannesburg, South Africa
| | - Matthew S Kelly
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
| | - David M Goldfarb
- Department of Pathology and Laboratory Medicine, The University of British Columbia Faculty of Medicine, Vancouver, British Columbia, Canada
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45
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Abstract
PURPOSE OF REVIEW This review describes recent findings about the burden of bacterial diarrhoea and its potential complications, newer diagnostics, the emerging threat of multidrug resistance, and the promise of vaccines in development. RECENT FINDINGS Introduction of rotavirus vaccines in over 110 countries has changed the landscape of diarrheal pathogens. In upper middle and high-income countries, the incidence of rotavirus-specific and all-cause gastroenteritis has declined substantially, and norovirus has become the major pathogen in many settings. Bacterial pathogens cause approximately 10-15% of episodes, most often Shigella, nontyphoidal Salmonella (NTS) Campylobacter and Shiga toxin-producing Escherichia coli (STEC). In lower income countries, bacterial pathogens remain a major cause of medically attended diarrhoea with Shigella, Campylobacter and enterotoxigenic Escherichia coli (ETEC) predominating. Multidrug-resistant strains of Shigella, NTS and, Campylobacter have emerged globally requiring judicious use of antibiotics according to current guidance. SUMMARY Management of bacterial diarrhoea includes standard fluid and electrolyte therapy, vigilance for potential complications, and use of antibiotics for children who have moderate-severe illness due to pathogens for which efficacy has been demonstrated, or for those at high risk for severe disease. The threat of multiply resistant strains provides impetus for preventive strategies such as development of vaccines.
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Affiliation(s)
- Karen L Kotloff
- Division of Infectious Disease and Tropical Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
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46
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Pavlinac PB, Rogawski McQuade ET, Platts-Mills JA, Kotloff KL, Deal C, Giersing BK, Isbrucker RA, Kang G, Ma LF, MacLennan CA, Patriarca P, Steele D, Vannice KS. Pivotal Shigella Vaccine Efficacy Trials-Study Design Considerations from a Shigella Vaccine Trial Design Working Group. Vaccines (Basel) 2022; 10:489. [PMID: 35455238 PMCID: PMC9032541 DOI: 10.3390/vaccines10040489] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 01/27/2023] Open
Abstract
Vaccine candidates for Shigella are approaching phase 3 clinical trials in the target population of young children living in low- and middle-income countries. Key study design decisions will need to be made to maximize the success of such trials and minimize the time to licensure and implementation. We convened an ad hoc working group to identify the key aspects of trial design that would meet the regulatory requirements to achieve the desired indication of prevention of moderate or severe shigellosis due to strains included in the vaccine. The proposed primary endpoint of pivotal Shigella vaccine trials is the efficacy of the vaccine against the first episode of acute moderate or severe diarrhea caused by the Shigella strains contained within the vaccine. Moderate or severe shigellosis could be defined by a modified Vesikari score with dysentery and molecular detection of vaccine-preventable Shigella strains. This report summarizes the rationale and current data behind these considerations, which will evolve as new data become available and after further review and consultation by global regulators and policymakers.
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Affiliation(s)
- Patricia B. Pavlinac
- Departments of Global Health and Epidemiology, University of Washington, Seattle, WA 98105, USA
| | | | - James A. Platts-Mills
- Department of Medicine, Infectious Diseases and International Health, University of Virginia, Charlottesville, VA 22908, USA;
| | - Karen L. Kotloff
- Department of Pediatrics, Medicine, Epidemiology, and Public Health, University of Maryland, Baltimore, MD 21201, USA;
| | - Carolyn Deal
- Enteric and Sexually Transmitted Infections Branch, National Institutes of Health, Rockvile, MD 20892, USA;
| | - Birgitte K. Giersing
- Immunization, Vaccines, and Biologicals Department, World Health Organization, 1211 Geneva, Switzerland; (B.K.G.); (R.A.I.)
| | - Richard A. Isbrucker
- Immunization, Vaccines, and Biologicals Department, World Health Organization, 1211 Geneva, Switzerland; (B.K.G.); (R.A.I.)
| | - Gagandeep Kang
- Department of Gastrointestinal Sciences, Christian Medical College, Vellore 632004, Tamil Nadu, India;
| | - Lyou-Fu Ma
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Calman A. MacLennan
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Peter Patriarca
- Bill & Melinda Gates Medical Research Institute, Cambridge, MA 02139, USA;
| | - Duncan Steele
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
| | - Kirsten S. Vannice
- Enteric and Diarrheal Diseases Program Strategy Team, Bill & Melinda Gates Foundation, Seattle, WA 98102, USA; (L.-F.M.); (C.A.M.); (D.S.); (K.S.V.)
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47
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Enterotoxigenic Escherichia coli enterotoxins regulate epithelial to immune relay of IL-33 and IL-1Ra cytokines. Infect Immun 2022; 90:e0063721. [PMID: 35191758 DOI: 10.1128/iai.00637-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) remain a major cause of diarrheal mortality and morbidity in children in low-resource settings. Few studies have explored the consequences of simultaneous intoxication with heat-stable (ST) and heat-labile (LT) enterotoxins despite the increased prevalence of wild ETEC isolates expressing both toxins. We therefore used a combination of tissue culture and murine models to explore the impact of simultaneous ST+LT intoxication of epithelial and myeloid cell responses. We report that LT induces sustained IL-33 and IL-1Ra responses in T84 intestinal epithelial cells via cAMP-production and protein kinase A activation. We demonstrate that combined ST+LT intoxication hastens epithelial transcriptional responses induced more slowly by LT alone. ST- and LT-mediated luminal fluid accumulation in vivo correlates with significant increases in IL-33 and IL-1Ra in small intestinal mucosal scrapings. Additionally, IL-33 receptor (IL-33R)-deficient mice are less susceptible to ST-mediated secretion. In the immune compartment, IL-33 is sensed by myeloid cells, and LT suppresses IL-33-induced TNFα secretion from macrophages but amplifies IL-33-mediated induction of IL-6 from bone marrow-derived dendritic cells. In conclusion, our studies suggest that enterotoxin-induced IL-33 and IL-1Ra modulate intestinal inflammation and IL-1 receptor signaling in the intestinal mucosa in response to ETEC enterotoxins.
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48
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Khan SM, Zhang X, Witola WH. Cryptosporidium parvum Pyruvate Kinase Inhibitors With in vivo Anti-cryptosporidial Efficacy. Front Microbiol 2022; 12:800293. [PMID: 35046922 PMCID: PMC8761912 DOI: 10.3389/fmicb.2021.800293] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/09/2021] [Indexed: 11/13/2022] Open
Abstract
Cryptosporidium parvum is a highly prevalent protozoan parasite that causes a diarrheal disease in humans and animals worldwide. Thus far, the moderately effective nitazoxanide is the only drug approved by the United States Food and Drug Administration for treating cryptosporidiosis in immunocompetent humans. However, no effective drug exists for the severe disease seen in young children, immunocompromised individuals and neonatal livestock. C. parvum lacks the Krebs cycle and the oxidative phosphorylation steps, making it dependent solely on glycolysis for metabolic energy production. Within its glycolytic pathway, C. parvum possesses two unique enzymes, the bacterial-type lactate dehydrogenase (CpLDH) and the plant-like pyruvate kinase (CpPyK), that catalyze two sequential steps for generation of essential metabolic energy. We have previously reported that inhibitors of CpLDH are effective against C. parvum, both in vitro and in vivo. Herein, we developed an in vitro assay for the enzymatic activity of recombinant CpPyK protein and used it to screen a chemical compound library for inhibitors of CpPyK’s activity. The identified inhibitors were tested (at non-toxic concentrations) for efficacy against C. parvum using in vitro assays, and an in vivo mouse infection model. We identified six CpPyK inhibitors that blocked in vitro growth and proliferation of C. parvum at low micromolar concentrations (EC50 values ranging from 10.29 to 86.01 μM) that were non-toxic to host cells. Among those six compounds, two (NSC252172 and NSC234945) were found to be highly efficacious against cryptosporidiosis in immunocompromised mice at a dose of 10 mg/kg body weight, with very significant reduction in parasite load and amelioration of intestinal pathologies. Together, these findings have unveiled inhibitors for an essential molecular target in C. parvum and demonstrated their efficacy against the parasite in vitro and in vivo. These inhibitors are, therefore, potential lead-compounds for developing efficacious treatments for cryptosporidiosis.
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Affiliation(s)
- Shahbaz M Khan
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Xuejin Zhang
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - William H Witola
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
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