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Puchner KP, Bottazzi ME, Periago V, Grobusch M, Maizels R, McCarthy J, Lee B, Gaspari E, Diemert D, Hotez P. Vaccine value profile for Hookworm. Vaccine 2024; 42:S25-S41. [PMID: 37863671 DOI: 10.1016/j.vaccine.2023.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 04/24/2023] [Accepted: 05/03/2023] [Indexed: 10/22/2023]
Abstract
Hookworm, a parasitic infection, retains a considerable burden of disease, affecting the most underprivileged segments of the general population in endemic countries and remains one of the leading causes of mild to severe anemia in Low and Middle Income Countries (LMICs), particularly in pregnancy and children under 5. Despite repeated large scale Preventive Chemotherapy (PC) interventions since more than 3 decades, there is broad consensus among scholars that elimination targets set in the newly launched NTD roadmap will require additional tools and interventions. Development of a vaccine could constitute a promising expansion of the existing arsenal against hookworm. Therefore, we have evaluated the biological and implementation feasibility of the vaccine development as well as the added value of such a novel tool. Based on pipeline landscaping and the current knowledge on key biological aspects of the pathogen and its interactions with the host, we found biological feasibility of development of a hookworm vaccine to be moderate. Also, our analysis on manufacturing and regulatory issues as well as potential uptake yielded moderate implementation feasibility. Modelling studies suggest a that introduction of a vaccine in parallel with ongoing integrated interventions (PC, WASH, shoe campaigns), could substantially reduce burden of disease in a cost - saving mode. Finally a set of actions are recommended that might impact positively the likelihood of timely development and introduction of a hookworm vaccine.
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Affiliation(s)
| | - Maria Elena Bottazzi
- National School of Tropical Medicine, Baylor College of Medicine, Baylor, TX, USA
| | | | - Martin Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, Amsterdam Infection & Immunity, Amsterdam Public Health, University of Amsterdam, Amsterdam, The Netherlands
| | - Rick Maizels
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - James McCarthy
- The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Bruce Lee
- Public Health Informatics, Computational, and Operations Research, Graduate School of Public Health and Health Policy, City University of New York, New York, NY, USA
| | - Erika Gaspari
- European & Developing Countries Clinical Trials Partnership (EDCTP), The Hague, The Netherlands
| | - David Diemert
- Department of Microbiology, Immunology & Tropical Medicine, George Washington University Medical Center, Washington, DC, USA
| | - Peter Hotez
- National School of Tropical Medicine, Baylor College of Medicine, Baylor, TX, USA
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2
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Zinsou JF, Diemert DJ, Dejon-Agobé JC, Adégbité BR, Honkpehedji YJ, Vodonou KG, Bikangui R, Edoa JR, Massinga Loembe M, Li G, Yazdanbakhsh M, Bottazzi ME, van Leeuwen R, Kremsner PG, Hotez PJ, Bethony JM, Grobusch MP, Adegnika AA. Safety and immunogenicity of the co-administered Na-APR-1 and Na-GST-1 hookworm vaccines in school-aged children in Gabon: a randomised, controlled, observer-blind, phase 1, dose-escalation trial. THE LANCET. INFECTIOUS DISEASES 2024; 24:760-774. [PMID: 38513684 DOI: 10.1016/s1473-3099(24)00104-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/07/2024] [Accepted: 02/08/2024] [Indexed: 03/23/2024]
Abstract
BACKGROUND A human hookworm vaccine is being developed to protect children against iron deficiency and anaemia associated with chronic infection with hookworms. Necator americanus aspartic protease-1 (Na-APR-1) and N americanus glutathione S-transferase-1 (Na-GST-1) are components of the blood digestion pathway critical to hookworm survival in the host. Recombinant Na-GST-1 and catalytically inactive Na-APR-1 (Na-APR-1[M74]) adsorbed to Alhydrogel were safe and immunogenic when delivered separately or co-administered to adults in phase 1 trials in non-endemic and endemic areas. We aimed to investigate the safety and immunogenicity of these antigens in healthy children in a hookworm-endemic area. METHODS This was a randomised, controlled, observer-blind, phase 1, dose-escalation trial, conducted in a clinical research centre, in 60 children aged six to ten years in Lambaréné, a hookworm-endemic region of Gabon. Healthy children (determined by clinical examination and safety laboratory testing) were randomised 4:1 to receive co-administered Na-GST-1 on Alhydrogel plus Na-APR-1(M74) on Alhydrogel and glucopyranosyl lipid A in aqueous formulation (GLA-AF), or co-administered ENGERIX-B hepatitis B vaccine (HBV) and saline placebo, injected into the deltoid of each arm. Allocation to vaccine groups was observer-masked. In each vaccine group, children were randomised 1:1 to receive intramuscular injections into each deltoid on two vaccine schedules, one at months 0, 2, and 4 or at months 0, 2, and 6. 10 μg, 30 μg, and 100 μg of each antigen were administered in the first, second, and third cohorts, respectively. The intention-to-treat population was used for safety analyses; while for immunogenicity analyses, the per-protocol population was used (children who received all scheduled vaccinations). The primary outcome was to evaluate the vaccines' safety and reactogenicity in healthy children aged between six and ten years. The secondary outcome was to measure antigen-specific serum IgG antibody levels at pre-vaccination and post-vaccination timepoints by qualified ELISAs. The trial is registered with ClinicalTrials.gov, NCT02839161, and is completed. FINDINGS Between Jan 23 and Oct 3, 2017, 137 children were screened, of whom 76 were eligible for this trial. 60 children were recruited, and allocated to either 10 μg of the co-administered antigens (n=8 for each injection schedule), 30 μg (n=8 for each schedule), 100 μg (n=8 for each schedule), or HBV and placebo (n=6 for each schedule) in three sequential cohorts. Co-administration of the vaccines was well tolerated; the most frequent solicited adverse events were mild-to-moderate injection-site pain, observed in up to 12 (75%) of 16 participants per vaccine group, and mild headache (12 [25%] of 48) and fever (11 [23%] of 48). No vaccine-related serious adverse events were observed. Significant anti-Na-APR-1(M74) and anti-Na-GST-1 IgG levels were induced in a dose-dependent manner, with peaks seen 14 days after the third vaccinations, regardless of dose (for Na-APR-1[M74], geometric mean levels [GML]=2295·97 arbitrary units [AU] and 726·89 AU, while for Na-GST-1, GMLs=331·2 AU and 21·4 AU for the month 0, 2, and 6 and month 0, 2, and 4 schedules, respectively). The month 0, 2, and 6 schedule induced significantly higher IgG responses to both antigens (p=0·01 and p=0·04 for Na-APR-1[M74] and Na-GST-1, respectively). INTERPRETATION Co-administration of recombinant Na-APR-1(M74) and Na-GST-1 to school-aged Gabonese children was well tolerated and induced significant IgG responses. These results justify further evaluation of this antigen combination in proof-of-concept controlled-infection and efficacy studies in hookworm-endemic areas. FUNDING European Union Seventh Framework Programme.
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Affiliation(s)
- Jeannot F Zinsou
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tübingen and German Center for Infection Research, Tübingen, Germany; Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin
| | - David J Diemert
- Department of Medicine, School of Medicine and Health Sciences, The George Washington University, Washington DC, USA; Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington DC, USA.
| | | | - Bayodé R Adégbité
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tübingen and German Center for Infection Research, Tübingen, Germany; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Yabo Josiane Honkpehedji
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin; Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Kafui G Vodonou
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Rodrigue Bikangui
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Jean Ronald Edoa
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | | | - Guangzhao Li
- Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington DC, USA
| | - Maria Yazdanbakhsh
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Maria Elena Bottazzi
- Departments of Pediatrics, Division of Pediatric Tropical Medicine, and Molecular Virology and Microbiology, Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Remko van Leeuwen
- Amsterdam Institute for Global Development (AIGHD), Amsterdam, Netherlands
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tübingen and German Center for Infection Research, Tübingen, Germany
| | - Peter J Hotez
- Departments of Pediatrics, Division of Pediatric Tropical Medicine, and Molecular Virology and Microbiology, Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Jeffrey M Bethony
- Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington DC, USA
| | - Martin P Grobusch
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tübingen and German Center for Infection Research, Tübingen, Germany; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, Netherlands; Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Ayola A Adegnika
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon; Institut für Tropenmedizin, Universität Tübingen and German Center for Infection Research, Tübingen, Germany; Fondation pour la Recherche Scientifique (FORS), Cotonou, Benin; Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
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Allen T, Castellanos ME, Giacomin P, Karunaweera ND, Kupz A, Lol JC, Sharma D, Sikder S, Tedla B, van Eijk L, Vojisavljevic D, Zhao G, Pai S. Next-generation vaccines for tropical infectious diseases. Int J Infect Dis 2024; 143:107014. [PMID: 38499058 DOI: 10.1016/j.ijid.2024.107014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 03/05/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024] Open
Abstract
Tropical infectious diseases inflict an unacceptable burden of disease on humans living in developing countries. Although anti-pathogenic drugs have been widely used, they carry a constant threat of selecting for resistance. Vaccines offer a promising means by which to enhance the global control of tropical infectious diseases; however, these have been difficult to develop, mostly because of the complex nature of the pathogen lifecycles. Here, we present recently developed vaccine candidates for five tropical infectious diseases in the form of a catalog that have either entered clinical trials or have been licensed for use. We deliberate on recently licensed dengue vaccines, provide evidence why combination vaccination could have a synergistic impact on schistosomiasis, critically appraise the value of typhoid conjugate vaccines, and discuss the potential of vaccines in the efforts to eliminate vivax malaria and hookworms.
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Affiliation(s)
- Tammy Allen
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Australia
| | - Maria Eugenia Castellanos
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Australia; Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Paul Giacomin
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | | | - Andreas Kupz
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Juan Carlos Lol
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Dileep Sharma
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia; College of Medicine & Dentistry, James Cook University, Cairns, Australia; School of Health Sciences, College of Health Medicine and Wellbeing, The University of Newcastle, Ourimbah, Australia
| | - Suchandan Sikder
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Bemnet Tedla
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia; Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Liza van Eijk
- Department of Psychology, James Cook University, Townsville, Australia
| | - Danica Vojisavljevic
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Australia; Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Guangzu Zhao
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Saparna Pai
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia.
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Nguema Moure PA, Nzamba Maloum M, Manouana GP, Laclong Lontchi RA, Mbong Ngwese M, Edoa JR, Fréjus Zinsou J, Meulah B, Mahmoudou S, N'noh Dansou EM, Josiane Honkpehedji Y, Romeo Adegbite B, Agnandji ST, Ramharter M, Lell B, Borrmann S, Kremsner PG, Dejon-Agobé JC, Adegnika AA. A randomized assessors-blind clinical trial to evaluate the safety and the efficacy of albendazole alone and in combination with mebendazole or pyrantel for the treatment of Trichuris trichiura infection in school-aged children in Lambaréné and surroundings. Antimicrob Agents Chemother 2024; 68:e0121123. [PMID: 38563751 PMCID: PMC11064543 DOI: 10.1128/aac.01211-23] [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: 09/19/2023] [Accepted: 03/05/2024] [Indexed: 04/04/2024] Open
Abstract
Helminthiasis remains a public health issue in endemic areas. Various drugs have been proposed to improve efficacy against helminths. The study aimed to assess the safety and efficacy of three different anthelmintic combinations to treat Trichuris trichiura infections. We conducted a randomized assessors-blind clinical trial involving children aged 2-17 years with T. trichiura. Participants were randomly assigned to one of three treatment arms. On the first and third days, all participants got albendazole 400 mg, and on the second day, albendazole (arm A), mebendazole 500 mg (arm B), or pyrantel 125 mg/kg (arm C). We assessed treatment efficacy using the cure rate (CR) and egg reduction rate (ERR) at 3 and 6 weeks post-treatment. At 3 weeks post-treatment, ERR and CR were highest in study arm A [ERR = 94%, 95% confidence interval (CI): 92-95; CR = 71%; 95% CI: 58-81] compared to the B and C arms. Decrease in ERR was significant only for arm B versus arm A (P-value <0.001); decrease in ERR was significant for arms B and C (P-value <0.001). No statistical difference was observed in CR when comparing arms A and B (P-value =1.00) and C (P-value =0.27). At 6 weeks, a decrease in ERR was observed in three arms, significant only for arm C, 81% (95% CI: 78-83). A significant increase in egg counts was observed between 3 and 6 weeks post-treatment. All treatments were safe with mild adverse events. Albendazole 400 mg/day (arm A) showed the highest efficacy against trichuriasis. Nonetheless, this treatment regimen was able to cure half of the treated individuals highlighting concerns about controlling the transmission of T. trichiura.CLINICAL TRIALRegistered at ClinicalTrials.gov (NCT04326868).
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Affiliation(s)
- Paul Alvyn Nguema Moure
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Ecole Doctorale Régionale d’Afrique Centrale en Infectiologie Tropicale de Franceville, Franceville, Gabon
| | | | - Gédéon Prince Manouana
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
| | | | | | | | - Jeannot Fréjus Zinsou
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
| | - Brice Meulah
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands
| | | | | | - Yabo Josiane Honkpehedji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands
| | - Bayode Romeo Adegbite
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Dep. of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Division of Infectious Diseases and Tropical Medicine, Department of Medicine 1, Medical University of Vienna, Vienna, Austria
| | - Steffen Borrmann
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Peter G. Kremsner
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | | | - Ayôla Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Ecole Doctorale Régionale d’Afrique Centrale en Infectiologie Tropicale de Franceville, Franceville, Gabon
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Universität Tübingen, Tübingen, Germany
- Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands
- German Center for Infection Research (DZIF), Tübingen, Germany
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5
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Hotez PJ. A Journey in Science: Molecular vaccines for global child health in troubled times of anti-science. Mol Med 2024; 30:37. [PMID: 38491420 PMCID: PMC10943906 DOI: 10.1186/s10020-024-00786-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2024] Open
Abstract
My scientific life in translational medicine runs in two parallel, yet often converging paths. The first, is four-decade-long commitment to develop new vaccines for parasitic and neglected tropical diseases, as well as pandemic threats. This includes a vaccine for human hookworm infection that I began as an MD-PhD student in New York City in the 1980s, and a new low-cost COVID vaccine that reached almost 100 million people in low- and middle-income countries. Alongside this life in scientific research, is one in public engagement for vaccine and neglected disease diplomacy to ensure that people who live in extreme poverty can benefit from access to biomedical innovations. A troubling element has been the daunting task of countering rising antivaccine activism, which threatens to undermine our global vaccine ecosystem. Yet, this activity may turn out to become just as important for saving lives as developing new vaccines.
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Affiliation(s)
- Peter J Hotez
- Texas Children's Hospital Center for Vaccine Development, Departments of Pediatrics and Molecular Virology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, 77030, USA.
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6
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Wong MTJ, Anuar NS, Noordin R, Tye GJ. Generation of IgG antibodies against Strongyloides stercoralis in mice via immunization with recombinant antigens A133 and Ss-IR. Acta Trop 2024; 251:107122. [PMID: 38246399 DOI: 10.1016/j.actatropica.2024.107122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/16/2023] [Accepted: 01/13/2024] [Indexed: 01/23/2024]
Abstract
Strongyloidiasis, caused by the nematode Strongyloides stercoralis, remains a threat to global public health, and a vaccine would be useful to control the disease, especially in developing countries. This study aimed to evaluate the efficacy of recombinant proteins, A133 and Ss-IR, as potential vaccine candidates against strongyloidiasis by investigating the humoral and cellular immune responses in immunized mice. Respective antigens were adjuvanted with Complete Freund's Adjuvant (prime) and Incomplete Freund's Adjuvant (boost) and administered intraperitoneally (prime) and subcutaneously (boost) to female BALB/c mice. For antigen-only doses, only antigens were injected without adjuvants. Altogether, 1 prime dose, 4 booster doses, and 2 antigen-only doses were administered successively. ELISAs were conducted to assess the antibody responses, along with flow cytometry and cytokine ELISA to elucidate the cellular immune responses. Results showed that A133 and Ss-IR induced the production of IgG1 and IgG2a, with A133 generating more robust IgG2a responses than Ss-IR. Flow cytometry findings indicated that effector CD8+T-cells and memory B-cells activity were upregulated significantly for A133 only, whereas cytokine ELISA demonstrated that a Th1/Th2/Th17 mixed cell responses were triggered upon vaccination with either antigen. This preliminary study illustrated the good potential of recombinant A133 and Ss-IR as vaccine candidates against S. stercoralis. It provided information on the probable immune mechanism involved in host defence and the elicitation of protection against S. stercoralis.
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Affiliation(s)
- Matthew Tze Jian Wong
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
| | - Nor Suhada Anuar
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia; Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Gee Jun Tye
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia.
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Oyeyemi OT, Ogundahunsi O, Schunk M, Fatem RG, Shollenberger LM. Neglected tropical disease (NTD) diagnostics: current development and operations to advance control. Pathog Glob Health 2024; 118:1-24. [PMID: 37872790 PMCID: PMC10769148 DOI: 10.1080/20477724.2023.2272095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023] Open
Abstract
Neglected tropical diseases (NTDs) have become important public health threats that require multi-faceted control interventions. As late treatment and management of NTDs contribute significantly to the associated burdens, early diagnosis becomes an important component for surveillance and planning effective interventions. This review identifies common NTDs and highlights the progress in the development of diagnostics for these NTDs. Leveraging existing technologies to improve NTD diagnosis and improving current operational approaches for deployment of developed diagnostics are crucial to achieving the 2030 NTD elimination target. Point-of-care NTD (POC-NTD) diagnostic tools are recommended preferred diagnostic options in resource-constrained areas for mapping risk zones and monitoring treatment efficacy. However, few are currently available commercially. Technical training of remote health care workers on the use of POC-NTD diagnostics, and training of health workers on the psychosocial consequences of these diagnostics are critical in harnessing POC-NTD diagnostic potential. While the COVID-19 pandemic has challenged the possibility of achieving NTD elimination in 2030 due to the disruption of healthcare services and dwindling financial support for NTDs, the possible contribution of NTDs in exacerbating COVID-19 pandemic should motivate NTD health system strengthening.
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Affiliation(s)
- Oyetunde T. Oyeyemi
- Department of Biosciences and Biotechnology, University of Medical Sciences, Ondo, Nigeria
- Department of Biological Sciences, Old Dominion University, Virginia, USA
| | - Olumide Ogundahunsi
- The Central Office for Research and Development (CORD), University of Medical Sciences, Ondo, Nigeria
| | - Mirjam Schunk
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich (LMU) institution, Munich, Germany
| | - Ramzy G. Fatem
- Schistosome Biological Supply Center, Theodor Bilharz Research Institute, Giza, Egypt
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8
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Kim CL, Agampodi S, Marks F, Kim JH, Excler JL. Mitigating the effects of climate change on human health with vaccines and vaccinations. Front Public Health 2023; 11:1252910. [PMID: 37900033 PMCID: PMC10602790 DOI: 10.3389/fpubh.2023.1252910] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 09/04/2023] [Indexed: 10/31/2023] Open
Abstract
Climate change represents an unprecedented threat to humanity and will be the ultimate challenge of the 21st century. As a public health consequence, the World Health Organization estimates an additional 250,000 deaths annually by 2030, with resource-poor countries being predominantly affected. Although climate change's direct and indirect consequences on human health are manifold and far from fully explored, a growing body of evidence demonstrates its potential to exacerbate the frequency and spread of transmissible infectious diseases. Effective, high-impact mitigation measures are critical in combating this global crisis. While vaccines and vaccination are among the most cost-effective public health interventions, they have yet to be established as a major strategy in climate change-related health effect mitigation. In this narrative review, we synthesize the available evidence on the effect of climate change on vaccine-preventable diseases. This review examines the direct effect of climate change on water-related diseases such as cholera and other enteropathogens, helminthic infections and leptospirosis. It also explores the effects of rising temperatures on vector-borne diseases like dengue, chikungunya, and malaria, as well as the impact of temperature and humidity on airborne diseases like influenza and respiratory syncytial virus infection. Recent advances in global vaccine development facilitate the use of vaccines and vaccination as a mitigation strategy in the agenda against climate change consequences. A focused evaluation of vaccine research and development, funding, and distribution related to climate change is required.
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Affiliation(s)
- Cara Lynn Kim
- International Vaccine Institute, Seoul, Republic of Korea
| | - Suneth Agampodi
- International Vaccine Institute, Seoul, Republic of Korea
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Florian Marks
- International Vaccine Institute, Seoul, Republic of Korea
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
- Madagascar Institute for Vaccine Research, University of Antananarivo, Antananarivo, Madagascar
- Heidelberg Institute of Global Health, University of Heidelberg, Heidelberg, Germany
| | - Jerome H. Kim
- International Vaccine Institute, Seoul, Republic of Korea
- College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
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Easland E, Biendl S, Keiser J. Development of a hookworm egg hatching assay to determine the ovicidal effects of anthelminthics. Parasit Vectors 2023; 16:157. [PMID: 37143169 PMCID: PMC10161531 DOI: 10.1186/s13071-023-05771-8] [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: 02/16/2023] [Accepted: 04/09/2023] [Indexed: 05/06/2023] Open
Abstract
BACKGROUND Few anthelminthics are currently available, manifesting the urgent need for new treatment options. In vitro profiling of current anthelminthics against larval and adult stage helminths displayed varying effects on closely related worm species and between life stages of the same species. Conversely, limited research has been performed on the egg stage of human hookworms, and the effects of investigational compounds on the egg stage are not routinely assessed. METHODS We profiled the development and hatching of Heligmosomoides polygyrus, Ancylostoma duodenale and Necator americanus eggs isolated from rodent faeces in liquid media with various nutrient levels, osmolar concentrations, and acidities in dependence on incubation temperature and light exposure. Incubation conditions were optimised to allow the study of drug effect on immature and embryonated eggs. We analysed concentration-effect relationships of commercially available anthelminthics over 72 h. RESULTS Rapid embryonation and hatching were observed at room temperature with and without light exposure without nutrient supplementation in a wide range of acidities. Hookworms hatched optimally at room temperature in PBS achieving > 75% hatching over 34 h. Developmental delays were seen when eggs were stored at 4 °C with no effect on viability. Similar delays were also seen with increased osmolar concentrations resulting in decreased viability. Benzimidazole anthelminthics effectively reduced the viability and prevented hatching of hookworm eggs, with albendazole and thiabendazole eliciting particularly potent effects at EC50 values below 1 µM. Macrolide anthelminthics as well as emodepside, oxantel pamoate, and pyrantel pamoate were inactive while monepantel, levamisole, and tribendimidine displayed varied potencies among the hookworm species. CONCLUSION The presented egg-hatching assay will complement ongoing anthelminthic drug discovery and allow a full characterisation of drug activity against all life stages. In the development and application of the egg-hatching assay, good accordance was observed between the three hookworm species evaluated. Marketed anthelminthics show differences of drug action compared to larval and adult stages highlighting the importance of profiling drug activity against all life stages.
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Affiliation(s)
- Erin Easland
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, 4003, Basel, Switzerland
| | - Stefan Biendl
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, 4003, Basel, Switzerland
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland.
- University of Basel, 4003, Basel, Switzerland.
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Wong MTJ, Anuar NS, Noordin R, Tye GJ. Soil-transmitted helminthic vaccines: Where are we now? Acta Trop 2023; 239:106796. [PMID: 36586174 DOI: 10.1016/j.actatropica.2022.106796] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/11/2022] [Accepted: 12/13/2022] [Indexed: 12/30/2022]
Abstract
It has been tested and proven that vaccination is still the best strategy to combat infectious diseases. However, to date, there are still no vaccines against human soil-transmitted helminthic diseases, despite their high prevalence globally, particularly in developing countries and rural areas with tropical climates and poor sanitation. The development of vaccines against helminths is riddled with obstacles. Helminths have a complex life cycle, multiple stages within the same host with stage-specific antigen expression, and the ability to regulate host immune reactions to evade the immune response. These elements contribute to the main challenge of helminthic vaccines: the identification of effective vaccine candidates. Therefore, this article reviews the current progress and potential future direction of soil-transmitted helminthic vaccines, particularly against Trichuris trichiura, Ascaris lumbricoides, Strongyloides stercoralis, Necator americanus and Ancylostoma duodenale. The study design employed was a systematic review, using qualitative meta-summary synthesis. Preclinical studies and clinical trials on the development of protein subunit vaccines against the five soil-transmitted helminths were searched on PubMed and Scopus. Effectiveness was indicated by a reduction in worm burden or larval output, an increase in specific IgG levels, or an increase in cytokine production. Our findings show that only the hookworm vaccine against N. americanus is in the clinical trial phase, while the rest is still in exploratory research and pre-clinical development phase.
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Affiliation(s)
- Matthew Tze Jian Wong
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia
| | - Nor Suhada Anuar
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia
| | - Gee Jun Tye
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia.
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11
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Yang Y, Zhou J, Wu F, Tong D, Chen X, Jiang S, Duan Y, Yao C, Wang T, Du A, Gasser RB, Ma G. Haem transporter HRG-1 is essential in the barber's pole worm and an intervention target candidate. PLoS Pathog 2023; 19:e1011129. [PMID: 36716341 PMCID: PMC9910794 DOI: 10.1371/journal.ppat.1011129] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 02/09/2023] [Accepted: 01/18/2023] [Indexed: 02/01/2023] Open
Abstract
Parasitic roundworms (nematodes) have lost genes involved in the de novo biosynthesis of haem, but have evolved the capacity to acquire and utilise exogenous haem from host animals. However, very little is known about the processes or mechanisms underlying haem acquisition and utilisation in parasites. Here, we reveal that HRG-1 is a conserved and unique haem transporter in a broad range of parasitic nematodes of socioeconomic importance, which enables haem uptake via intestinal cells, facilitates cellular haem utilisation through the endo-lysosomal system, and exhibits a conspicuous distribution at the basal laminae covering the alimentary tract, muscles and gonads. The broader tissue expression pattern of HRG-1 in Haemonchus contortus (barber's pole worm) compared with its orthologues in the free-living nematode Caenorhabditis elegans indicates critical involvement of this unique haem transporter in haem homeostasis in tissues and organs of the parasitic nematode. RNAi-mediated gene knockdown of hrg-1 resulted in sick and lethal phenotypes of infective larvae of H. contortus, which could only be rescued by supplementation of exogenous haem in the early developmental stage. Notably, the RNAi-treated infective larvae could not establish infection or survive in the mammalian host, suggesting an indispensable role of this haem transporter in the survival of this parasite. This study provides new insights into the haem biology of a parasitic nematode, demonstrates that haem acquisition by HRG-1 is essential for H. contortus survival and infection, and suggests that HRG-1 could be an intervention target candidate in a range of parasitic nematodes.
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Affiliation(s)
- Yi Yang
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jingru Zhou
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Fei Wu
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Danni Tong
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xueqiu Chen
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Shengjun Jiang
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yu Duan
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chaoqun Yao
- Department of Biomedical Sciences and One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, St. Kitts, West Indies
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Aifang Du
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- * E-mail: (AD); (RBG); (GM)
| | - Robin B. Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
- * E-mail: (AD); (RBG); (GM)
| | - Guangxu Ma
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
- * E-mail: (AD); (RBG); (GM)
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12
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Hotez PJ. Malnutrition vaccines for an imminent global food catastrophe. Trends Pharmacol Sci 2022; 43:994-997. [PMID: 36100482 PMCID: PMC9463047 DOI: 10.1016/j.tips.2022.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/15/2022] [Accepted: 08/17/2022] [Indexed: 01/13/2023]
Abstract
Together with climate change, both the geopolitical events in Ukraine and social disruptions in supply chains from the COVID-19 pandemic could produce global food shortages or even mass starvation events. Promising new interventions include vaccines to prevent infectious causes of malnutrition or infections disproportionately causing death among the malnourished.
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Affiliation(s)
- Peter J. Hotez
- Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA,Department of Biology, Baylor University, Waco, TX, USA,James A. Baker III Institute for Public Policy, Rice University, Houston, TX, USA,Hagler Institute for Advanced Study, and the Scrowcroft Institute of International Affairs, at Texas A&M University, College Station, TX, USA,Correspondence:
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13
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Safety and immunogenicity of the Na-APR-1 hookworm vaccine in infection-naïve adults. Vaccine 2022; 40:6084-6092. [PMID: 36114129 PMCID: PMC9549940 DOI: 10.1016/j.vaccine.2022.09.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 06/03/2022] [Accepted: 09/05/2022] [Indexed: 11/20/2022]
Abstract
Background The Necator americanus hemoglobinase, aspartic protease-1 (Na-APR-1), facilitates the ability of adult hookworms to parasitize the intestine of their human hosts. A recombinant version of APR-1 protected laboratory animals against hookworm infection by inducing neutralizing antibodies that block the protein’s enzymatic activity and thereby impair blood feeding. A catalytically inactive version of the wild-type hemoglobinase (Na-APR-1(M74)) was expressed by infiltrating Nicotiana benthamiana tobacco plants with an Agrobacterium tumefaciens strain engineered to express the vaccine antigen, which was adjuvanted with aluminum hydroxide adjuvant (Alhydrogel). Methods An open-label dose-escalation Phase 1 clinical trial was conducted in 40 healthy, hookworm-naïve adult volunteers in the United States. Participants received 30 or 100 µg of recombinant Na-APR-1(M74) with Alhydrogel or with Alhydrogel co-administered with one of two doses (2.5 or 5.0 µg) of an aqueous formulation of Glucopyranosyl Lipid A (GLA-AF). Intramuscular injections of study vaccine were administered on days 0, 56, and 112. Results Na-APR-1(M74)/Alhydrogel was well-tolerated; the most frequent adverse events were mild or moderate injection site tenderness and pain, and mild or moderate nausea and headache. No serious adverse events or adverse events of special interest related to vaccination were observed. Significantly higher levels of antigen-specific IgG antibodies were induced in those who received 100 µg Na-APR-1(M74) than those who received 30 µg of antigen. Adding GLA-AF to Na-APR-1(M74)/Alhydrogel resulted in higher levels of IgG against Na-APR-1(M74) in both the 30 and 100 µg Na-APR-1(M74) groups in comparison to the non-GLA formulations at the same antigen dose. Conclusions Vaccination of hookworm-naïve adults with recombinant Na-APR-1(M74) was well-tolerated, safe, and induced significant IgG responses against the vaccine antigen Na-APR-1(M74). Given these favorable results, clinical trials of this product were initiated in hookworm-endemic areas of Gabon and Brazil.
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14
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Zhan B, Bottazzi ME, Hotez PJ, Lustigman S. Advancing a Human Onchocerciasis Vaccine From Antigen Discovery to Efficacy Studies Against Natural Infection of Cattle With Onchocerca ochengi. Front Cell Infect Microbiol 2022; 12:869039. [PMID: 35444961 PMCID: PMC9015098 DOI: 10.3389/fcimb.2022.869039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/07/2022] [Indexed: 11/19/2022] Open
Abstract
Human onchocerciasis is a devastating neglected tropical disease caused by infection of the filarial nematode Onchocerca volvulus. The infection can cause irreversible visual impairment or blindness and stigmatizing dermatitis. More than 32 million people were estimated to be infected with O. volvulus in Africa, and 385,000 suffered from blindness. Even though the implementation of mass drug administration (MDA) with ivermectin has reduced the global prevalence of onchocerciasis, O. volvulus infection remains challenging to control because MDA with ivermectin cannot be implemented in endemic areas co-endemic with loiasis due to the risk of severe adverse events. There is also emerging drug resistance to ivermectin that further complicates the elimination of onchocerciasis. Thus, the development of a vaccine that would induce protective immunity and reduce infection burden is essential. Efforts to develop prophylactic and/or therapeutic vaccines for onchocerciasis have been explored since the late 1980s by many researchers and entities, and here we summarize the recent advances made in the development of vaccines against the infection of O. volvulus and onchocerciasis.
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Affiliation(s)
- Bin Zhan
- Texas Children’s Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, United States
| | - Maria Elena Bottazzi
- Texas Children’s Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, United States
| | - Peter J. Hotez
- Texas Children’s Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, United States
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, United States
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15
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Recombinant Expression and Antibacterial Properties of BmTXKS2 Venom Peptide in Fusion with GST. Int J Pept Res Ther 2022. [DOI: 10.1007/s10989-022-10374-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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The yin and yang of human soil-transmitted helminth infections. Int J Parasitol 2021; 51:1243-1253. [PMID: 34774540 PMCID: PMC9145206 DOI: 10.1016/j.ijpara.2021.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 12/22/2022]
Abstract
The major soil-transmitted helminths that infect humans are the roundworms, whipworms and hookworms. Soil-transmitted helminth infections rank among the most important neglected tropical diseases in terms of morbidity, and almost one billion people are still infected with at least one species. While anthelmintic drugs are available, they do not offer long term protection against reinfection, precipitating the need for vaccines that provide long-term immunologic defense. Vaccine discovery and development is in advanced clinical development for hookworm infection, with a bivalent human hookworm vaccine in clinical trials in Brazil and Africa, but is in its infancy for both roundworm (ascariasis) and whipworm (trichuriasis) infections. One of the greatest hurdles to developing soil-transmitted helminth vaccines is the potent immunoregulatory properties of these helminths, creating a barrier to the induction of meaningful long-term protective immunity. While challenging for vaccinologists, this phenomenon presents unique opportunities to develop an entirely new class of anti-inflammatory drugs that capitalise on these immunomodulatory strategies. Epidemiologic studies and clinical trials employing experimental soil-transmitted helminth challenge models, when coupled with findings from animal models, show that at least some soil-transmitted helminth-derived molecules can protect against the onset of autoimmune, allergic and metabolic disorders, and several natural products with the desired bioactivity have been isolated and tested in pre-clinical settings. The yin and yang of soil-transmitted helminth infections reflect both the urgency for effective vaccines and the potential for new immunoregulatory molecules from parasite products.
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17
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Mouwenda YD, Betouke Ongwe ME, Sonnet F, Stam KA, Labuda LA, De Vries S, Grobusch MP, Zinsou FJ, Honkpehedji YJ, Dejon Agobe JC, Diemert DJ, van Leeuwen R, Bottazzi ME, Hotez PJ, Kremsner PG, Bethony JM, Jochems SP, Adegnika AA, Massinga Loembe M, Yazdanbakhsh M. Characterization of T cell responses to co-administered hookworm vaccine candidates Na-GST-1 and Na-APR-1 in healthy adults in Gabon. PLoS Negl Trop Dis 2021; 15:e0009732. [PMID: 34597297 PMCID: PMC8486127 DOI: 10.1371/journal.pntd.0009732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 08/14/2021] [Indexed: 12/23/2022] Open
Abstract
Two hookworm vaccine candidates, Na-GST-1 and Na-APR-1, formulated with Glucopyranosyl Lipid A (GLA-AF) adjuvant, have been shown to be safe, well tolerated, and to induce antibody responses in a Phase 1 clinical trial (Clinicaltrials.gov NCT02126462) conducted in Gabon. Here, we characterized T cell responses in 24 Gabonese volunteers randomized to get vaccinated three times with Na-GST-1 and Na-APR-1 at doses of 30μg (n = 8) or 100μg (n = 10) and as control Hepatitis B (n = 6). Blood was collected pre- and post-vaccination on days 0, 28, and 180 as well as 2-weeks after each vaccine dose on days 14, 42, and 194 for PBMCs isolation. PBMCs were stimulated with recombinant Na-GST-1 or Na-APR-1, before (days 0, 28 and 180) and two weeks after (days 14, 42 and 194) each vaccination and used to characterize T cell responses by flow and mass cytometry. A significant increase in Na-GST-1 -specific CD4+ T cells producing IL-2 and TNF, correlated with specific IgG antibody levels, after the third vaccination (day 194) was observed. In contrast, no increase in Na-APR-1 specific T cell responses were induced by the vaccine. Mass cytometry revealed that, Na-GST-1 cytokine producing CD4+ T cells were CD161+ memory cells expressing CTLA-4 and CD40-L. Blocking CTLA-4 enhanced the cytokine response to Na-GST-1. In Gabonese volunteers, hookworm vaccine candidate, Na-GST-1, induces detectable CD4+ T cell responses that correlate with specific antibody levels. As these CD4+ T cells express CTLA-4, and blocking this inhibitory molecules resulted in enhanced cytokine production, the question arises whether this pathway can be targeted to enhance vaccine immunogenicity. Two hookworm vaccine candidate (Na-GST-1 and Na-APR-1) have been tested in Gabonese and found to be safe and to induce antibody response. We aimed to study the cellular immune responses among vaccinated and unvaccinated volunteers. We found that Na-GST-1 induced CD4+ T cell responses (IL-2, TNF) among the vaccinated volunteers that received the high vaccine dose (100 ug). Furthermore Na-GST-1 specific memory T cells were found to express the inhibitory molecule CTLA-4. These responses was not observed in those who received the low dose of the Na-GST-1 vaccine, or those who received Na-APR-1 or HBV. By blocking CTLA-4, we observed an increase in TNF production. Our data suggest that an intervention involving blockage of the CTLA-4 molecule in the vaccinated could be beneficial in endemic settings where vaccine responses have been shown to be lower compared to non-endemic settings.
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Affiliation(s)
- Yoanne D. Mouwenda
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- * E-mail:
| | - Madeleine E. Betouke Ongwe
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Centre National de la Recherche Scientifique et Technologique (IRET- CENAREST), Libreville, Gabon
| | - Friederike Sonnet
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Koen A. Stam
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Lucja A. Labuda
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Sophie De Vries
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, (AMC), University of Amsterdam, Amsterdam, the Netherlands
| | - Martin P. Grobusch
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, (AMC), University of Amsterdam, Amsterdam, the Netherlands
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Frejus J. Zinsou
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Yabo J. Honkpehedji
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - Jean-Claude Dejon Agobe
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, (AMC), University of Amsterdam, Amsterdam, the Netherlands
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
| | - David J. Diemert
- Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia, United States of America
| | - Remko van Leeuwen
- Amsterdam Institute for Global Development (AIGHD), Amsterdam, The Netherlands
| | - Maria E. Bottazzi
- Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Peter J. Hotez
- Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Peter G. Kremsner
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research, Tübingen, Germany
| | - Jeffrey M. Bethony
- Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia, United States of America
| | - Simon P. Jochems
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Ayola A. Adegnika
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research, Tübingen, Germany
| | | | - Maria Yazdanbakhsh
- Department of Parasitology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
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Shalash AO, Becker L, Yang J, Giacomin P, Pearson M, Hussein WM, Loukas A, Skwarczynski M, Toth I. Oral Peptide Vaccine against Hookworm Infection: Correlation of Antibody Titers with Protective Efficacy. Vaccines (Basel) 2021; 9:vaccines9091034. [PMID: 34579271 PMCID: PMC8472562 DOI: 10.3390/vaccines9091034] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 11/29/2022] Open
Abstract
Approximately 0.4 billion individuals worldwide are infected with hookworm. An effective vaccine is needed to not only improve the health of those affected and at high risk, but also to improve economic growth in disease-endemic areas. An ideal anti-hookworm therapeutic strategy for mass administration is a stable and orally administered vaccine. Oral vaccines are advantageous as they negate the need for trained medical staff for administration and do not require strict sterility conditions. Vaccination, therefore, can be carried out at a significantly reduced cost. One of the most promising current antigenic targets for hookworm vaccine development is the aspartic protease digestive enzyme (APR-1). Antibody-mediated neutralization of APR-1 deprives the worm of nourishment, leading to reduced worm burdens in vaccinated hosts. Previously, we demonstrated that, when incorporated into vaccine delivery systems, the APR-1-derived p3 epitope (TSLIAGPKAQVEAIQKYIGAEL) was able to greatly reduce worm burdens (≥90%) in BALB/c mice; however, multiple, large doses of the vaccine were required. Here, we investigated a variety of p3-antigen conjugates to optimize antigen delivery and establish immune response/protective efficacy relationships. We synthesized, purified, and characterized four p3 peptide-based vaccine candidates with: (a) lipidic (lipid core peptide (LCP)); (b) classical polymeric (polymethylacrylate (PMA)); and (c) novel polymeric (polyleucine in a branched or linear arrangement, BL10 or LL10, respectively) groups as self-adjuvanting moieties. BL10 and LL10 induced the highest serum anti-p3 and anti-APR-1 IgG titers. Upon challenge with rodent hookworms, the highest significant reduction in worm burden was observed in mice immunized with LL10. APR-1-specific serum IgG titers correlated with worm burden reduction. Thus, we provide the first vaccine-triggered immune response-protection relationship for hookworm infection.
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Affiliation(s)
- Ahmed O. Shalash
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (A.O.S.); (J.Y.); (W.M.H.); (I.T.)
| | - Luke Becker
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia; (L.B.); (P.G.); (M.P.); (A.L.)
| | - Jieru Yang
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (A.O.S.); (J.Y.); (W.M.H.); (I.T.)
| | - Paul Giacomin
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia; (L.B.); (P.G.); (M.P.); (A.L.)
| | - Mark Pearson
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia; (L.B.); (P.G.); (M.P.); (A.L.)
| | - Waleed M. Hussein
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (A.O.S.); (J.Y.); (W.M.H.); (I.T.)
| | - Alex Loukas
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia; (L.B.); (P.G.); (M.P.); (A.L.)
| | - Mariusz Skwarczynski
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (A.O.S.); (J.Y.); (W.M.H.); (I.T.)
- Correspondence:
| | - Istvan Toth
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (A.O.S.); (J.Y.); (W.M.H.); (I.T.)
- School of Pharmacy, The University of Queensland, Woolloongabba, QLD 4102, Australia
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19
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Perera DJ, Ndao M. Promising Technologies in the Field of Helminth Vaccines. Front Immunol 2021; 12:711650. [PMID: 34489961 PMCID: PMC8418310 DOI: 10.3389/fimmu.2021.711650] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 07/26/2021] [Indexed: 12/18/2022] Open
Abstract
Helminths contribute a larger global burden of disease than both malaria and tuberculosis. These eukaryotes have caused human infections since before our earliest recorded history (i.e.: earlier than 1200 B.C. for Schistosoma spp.). Despite the prevalence and importance of these infections, helminths are considered a neglected tropical disease for which there are no vaccines approved for human use. Similar to other parasites, helminths are complex organisms which employ a plethora of features such as: complex life cycles, chronic infections, and antigenic mimicry to name a few, making them difficult to target by conventional vaccine strategies. With novel vaccine strategies such as viral vectors and genetic elements, numerous constructs are being defined for a wide range of helminth parasites; however, it has yet to be discussed which of these approaches may be the most effective. With human trials being conducted, and a pipeline of potential anti-helminthic antigens, greater understanding of helminth vaccine-induced immunity is necessary for the development of potent vaccine platforms and their optimal design. This review outlines the conventional and the most promising approaches in clinical and preclinical helminth vaccinology.
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Affiliation(s)
- Dilhan J Perera
- Division of Experimental Medicine, McGill University, Montreal, QC, Canada.,Program of Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Momar Ndao
- Division of Experimental Medicine, McGill University, Montreal, QC, Canada.,Program of Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada.,National Reference Centre for Parasitology, Research Institute of McGill University Health Centre, Montreal, QC, Canada
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20
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Pritchard DI, Diemert D, Bottazzi ME, Hawdon JM, Correa-Oliveira R, Bethony JM. Controlled Infection of Humans with the Hookworm Parasite Necator americanus to Accelerate Vaccine Development : The Human Hookworm Vaccination/Challenge Model (HVCM). Curr Top Microbiol Immunol 2021. [PMID: 34328562 DOI: 10.1007/82_2021_237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In this chapter, we describe the scientific, technical, clinical and regulatory aspects of establishing a controlled human hookworm infection (CHHI) model in non-endemic and endemic geographical regions, to facilitate a pathway towards accelerated vaccine development. The success achieved in establishing the CHHI platform specifically allows the Human Hookworm Vaccine Initiative (HHVI) to accelerate its progress by establishing a human hookworm vaccination/challenge model (HVCM) in a hookworm endemic area of Brazil. The HVCM will permit the rapid and robust determination of clinical efficacy in adults, allowing for early selection of the most efficacious human hookworm vaccine (HHV) candidate(s) to advance into later-stage pivotal paediatric clinical trials and reduce the overall number of participants required to assess efficacy (Diemert et al. 2018).
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Affiliation(s)
- David I Pritchard
- Parasite Immunology, University of Nottingham, Nottingham, UK.
- HIC-Vac, London, UK.
| | - David Diemert
- Department of Medicine, The George Washington University, Washington, DC, USA
| | - Maria Elena Bottazzi
- Department of Pediatrics, Section of Pediatric Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - John M Hawdon
- Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC, USA
| | | | - Jeffrey M Bethony
- Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC, USA
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21
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Koopman JPR, Driciru E, Roestenberg M. Controlled human infection models to evaluate schistosomiasis and hookworm vaccines: where are we now? Expert Rev Vaccines 2021; 20:1369-1371. [PMID: 34225549 DOI: 10.1080/14760584.2021.1951244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jan Pieter R Koopman
- Department of Parasitology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Emmanuella Driciru
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene & Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Meta Roestenberg
- Department of Parasitology and Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands
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22
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Alabi A, Hussain M, Hoogerwerf MA, Mengome CN, Egesa M, Driciru E, Wammes LJ, Kruize YCM, Sartono E, Adegnika AA, Kremsner PG, Yazdanbakhsh M, Agnandji ST. Establishing a controlled hookworm human infection (CHHI) model for Africa: A report from the stakeholders meeting held in Lambaréné, Gabon, November 10-11, 2019. Arch Public Health 2021; 79:120. [PMID: 34225793 PMCID: PMC8256403 DOI: 10.1186/s13690-021-00650-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 06/21/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Hookworm is a major contributor to worldwide disease burden with over 230 million people infected. It has been identified as one of the Neglected Tropical Diseases that can be controlled and even eliminated through mass drug administration and other effective interventions. Mathematical models have shown that hookworm can only be eliminated via a vaccine. Controlled Hookworm Human Infection (CHHI) models can facilitate rapid development of vaccines and drugs. METHODS As a first step towards the establishment of CHHI in Africa, we held a stakeholders meeting in Lamberene, Gabon from 10 to 11 November 2019. RESULTS Discussions revolved around the roles of the different regulatory institutions concerned; the need to strengthen existing regulatory capacity and the role of legislation; creating Gabon-specific ethical guidelines to govern Controlled Human Infection (CHI) studies; development of a study protocol; consideration of cultural and social peculiarities; the need for regular joint review meetings between interested parties throughout the process of protocol implementation; and participant compensation. Moreover, operational considerations concerning the introduction of CHHI in Gabon include the use of the local strain of hookworm for the challenge infections, capacity building for the local production of challenge material, and the establishment of adequate quality assurance procedures. CONCLUSION The workshop addressed several of the anticipated hurdles to the successful implementation of CHHI in Gabon. It is our aim that this report will stimulate interest in the implementation of this model in the sub-Saharan African setting.
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Affiliation(s)
- Ayodele Alabi
- Centre de Recherches Médicales de Lambaréné, BP242, Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Mosarrof Hussain
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Marie-Astrid Hoogerwerf
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Moses Egesa
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene & Tropical Medicine Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
- Uganda Virus Research Institute, P.O. Box 49, Entebbe, Uganda
| | - Emmanuella Driciru
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene & Tropical Medicine Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | - Linda J. Wammes
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Yvonne C. M. Kruize
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Erliyani Sartono
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Ayola Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, BP242, Lambaréné, Gabon
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
- Fondation pour la Recherche Scientifique, 72 BP45 Cotonou, Bénin
| | - Peter G. Kremsner
- Centre de Recherches Médicales de Lambaréné, BP242, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Maria Yazdanbakhsh
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Selidji Todagbe Agnandji
- Centre de Recherches Médicales de Lambaréné, BP242, Lambaréné, Gabon
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
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23
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Zakzuk J, Lozano A, Caraballo L. Allergological Importance of Invertebrate Glutathione Transferases in Tropical Environments. FRONTIERS IN ALLERGY 2021; 2:695262. [PMID: 35387058 PMCID: PMC8974725 DOI: 10.3389/falgy.2021.695262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/19/2021] [Indexed: 11/19/2022] Open
Abstract
Glutathione-S transferases (GSTs) are part of a ubiquitous family of dimeric proteins that participate in detoxification reactions. It has been demonstrated that various GSTs induce allergic reactions in humans: those originating from house dust mites (HDM), cockroaches, and helminths being the best characterized. Evaluation of their allergenic activity suggests that they have a clinical impact. GST allergens belong to different classes: mu (Blo t 8, Der p 8, Der f 8, and Tyr p 8), sigma (Bla g 5 and Asc s 13), or delta (Per a 5). Also, IgE-binding molecules belonging to the pi-class have been discovered in helminths, but they are not officially recognized as allergens. In this review, we describe some aspects of the biology of GST, analyze their allergenic activity, and explore the structural aspects and clinical impact of their cross-reactivity.
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24
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Hayon J, Weatherhead J, Hotez PJ, Bottazzi ME, Zhan B. Advances in vaccine development for human trichuriasis. Parasitology 2021; 148:1-12. [PMID: 33757603 DOI: 10.1017/s0031182021000500] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Trichuriasis known as whipworm infection caused by Trichuris trichiura, is a highly prevalent soil-transmitted helminthiasis in low- and middle-income countries located in tropical and subtropical areas and affecting approximately 360 million people. Children typically harbour the largest burden of T. trichiura and they are usually co-infected with other soil-transmitted helminth (STH), including Ascaris lumbricoides and hookworm. The consequences of trichuriasis, such as malnutrition and physical and cognitive growth restriction, lead to a massive health burden in endemic regions. Despite the implementation of mass drug administration of anthelminthic treatment to school-age children, T. trichiura infection remains challenging to control due to the low efficacy of current drugs as well as high rates of post-treatment re-infection. Thus, the development of a vaccine that would induce protective immunity and reduce infection rate or community faecal egg output is essential. Hurdles for human whipworm vaccine development include the lack of suitable vaccine antigen targets and animal models for human T. trichiura infection. Instead, rodent whipworm T. muris infected mouse models serve as a major surrogate for testing immunogenicity and efficacy of vaccine candidates. In this review, we summarize recent advances in animal models for T. trichiura antigen discovery and testing of vaccine candidates, while providing an overall view of the current status of T. trichiura vaccine development.
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Affiliation(s)
- Jesica Hayon
- Department of Medicine, Section of Infectious Diseases, Baylor College of Medicine, Houston, TX, USA
| | - Jill Weatherhead
- Department of Medicine, Section of Infectious Diseases, Baylor College of Medicine, Houston, TX, USA
- Department of Pediatrics, Section of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Peter J Hotez
- Department of Pediatrics, Section of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX77030, USA
| | - Maria Elena Bottazzi
- Department of Pediatrics, Section of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX77030, USA
| | - Bin Zhan
- Department of Pediatrics, Section of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
- Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX77030, USA
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25
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Mondal R, Lahiri D, Deb S, Bandyopadhyay D, Shome G, Sarkar S, Paria SR, Thakurta TG, Singla P, Biswas SC. COVID-19: Are we dealing with a multisystem vasculopathy in disguise of a viral infection? J Thromb Thrombolysis 2020; 50:567-579. [PMID: 32627126 PMCID: PMC7335630 DOI: 10.1007/s11239-020-02210-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
After the emergence of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in the last two decades, the world is facing its new challenge in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic with unprecedented global response. With the expanding domain of presentations in COVID-19 patients, the full range of manifestations is yet to unfold. The classical clinical symptoms for SARS-CoV-2 affected patients are dry cough, high fever, dyspnoea, lethal pneumonia whereas many patients have also been found to be associated with a few additional signs and clinical manifestations of isolated vasculopathy. Albeit a deep and profound knowledge has been gained on the clinical features and management of COVID-19, less clear association has been provided on SARS-CoV-2 mediated direct or indirect vasculopathy and its possible correlation with disease prognosis. The accumulative evidences suggest that novel coronavirus, apart from its primary respiratory confinement, may also invade vascular endothelial cells of several systems including cerebral, cardio-pulmonary as well as renal microvasculature, modulating multiple visceral perfusion indices. Here we analyse the phylogenetic perspective of SARS-CoV-2 along with other strains of β-coronaviridae from a standpoint of vasculopathic derangements. Based on the existing case reports, literature and open data bases, we also analyse the differential pattern of vasculopathy related changes in COVID-19 positive patients. Besides, we debate the need of modulation in clinical approach from a hemodynamical point of view, as a measure towards reducing disease transmission, morbidity and mortality in SARS-CoV-2 affected patients.
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Affiliation(s)
- Ritwick Mondal
- Institute of Post Graduate Medical Education and Research, SSKM Hospital, 52/1A, S.N. Pandit Street, Kolkata, 700025, India
| | - Durjoy Lahiri
- Institute of Post Graduate Medical Education and Research, SSKM Hospital, 52/1A, S.N. Pandit Street, Kolkata, 700025, India.
| | - Shramana Deb
- S.N. Pradhan Centre for Neuroscience, University of Calcutta, Kolkata, India
| | - Deebya Bandyopadhyay
- Institute of Post Graduate Medical Education and Research, SSKM Hospital, 52/1A, S.N. Pandit Street, Kolkata, 700025, India
| | - Gourav Shome
- Department of Microbiology, University of Calcutta, Kolkata, India
| | - Sukanya Sarkar
- CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Sudeb R Paria
- Institute of Post Graduate Medical Education and Research, SSKM Hospital, 52/1A, S.N. Pandit Street, Kolkata, 700025, India
| | | | - Pratibha Singla
- Gian Sagar Medical College and Hospital, Patiala, Punjab, India
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