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Koh CC, Gollob KJ, Dutra WO. Balancing the functions of DNA extracellular traps in intracellular parasite infections: implications for host defense, disease pathology and therapy. Cell Death Dis 2023; 14:450. [PMID: 37474501 PMCID: PMC10359321 DOI: 10.1038/s41419-023-05994-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/22/2023] [Accepted: 07/13/2023] [Indexed: 07/22/2023]
Abstract
The release of DNA to the extracellular milieu is a biological process referred to as etosis, which is involved in both physiological and pathological functions. Although the release of DNA extracellular traps (ETs) was initially attributed to innate immune cells such as neutrophils, eosinophils, and macrophages, recent studies have shown that T cells, as well as non-immune cells, are capable of releasing ETs. These structures were described primarily for their potential to trap and kill pathogens, presenting an important strategy of host defense. Intriguingly, these functions have been associated with intracellular pathogens such as the parasites Leishmania sp. and Trypanosoma cruzi, causative agents of leishmaniasis and Chagas disease, respectively. These are two devastating tropical diseases that lead to thousands of deaths every year. In an apparent contradiction, ETs can also induce and amplify inflammation, which may lead to worsening disease pathology. This has prompted the concept of targeting ETs' release as a means of controlling tissue destruction to treat human diseases. What is the best approach to prevent disease severity: inducing ETs to kill pathogens or preventing their release? In this Perspective article, we will discuss the importance of understanding ETs released by different cell types and the need to balance their potentially complementary functions. In addition, we will explore other functions of ETs and their translational applications to benefit individuals infected with intracellular parasites and other pathogens. Ultimately, a better understanding of the role of ETs in disease pathogenesis will provide valuable insights into developing novel therapies for human diseases.
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Affiliation(s)
- Carolina Cattoni Koh
- Morphology Dept, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Kenneth J Gollob
- National Institute for Science & Technology in Tropical Diseases - INCT-DT, Belo Horizonte, MG, Brazil
- Albert Einstein Israelite Hospital, São Paulo, SP, Brazil
| | - Walderez O Dutra
- Morphology Dept, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
- National Institute for Science & Technology in Tropical Diseases - INCT-DT, Belo Horizonte, MG, Brazil.
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2
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Ramponi F, Aerts C, Sartor P, Pinazo MJ, Freilij H, Guzmán CA, Malchiodi E, Sicuri E. Development of vaccines for Chagas disease (CRUZIVAX): stakeholders' preferences and potential impacts on healthcare. GACETA SANITARIA 2022; 37:102275. [PMID: 36563537 DOI: 10.1016/j.gaceta.2022.102275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 10/14/2022] [Indexed: 12/24/2022]
Abstract
A vaccine for Chagas disease does not currently exist. This study aims to inform the development of two vaccines for the prevention and treatment of Trypanosoma cruzi infection, and guide their pre-clinical phase up to clinical phase I. The three main objectives are: 1) to explore patients' and policy makers' preferences on the candidate vaccines in Argentina and Spain; 2) to investigate health-related quality of life of patients affected by Chagas disease; and 3) to assess the potential health provider savings associated with the vaccines, in terms of resource use and health care costs. Discrete choice experiments will be employed to estimate and characterize the theoretical demand for the vaccines and investigate patients' and policy makers' preferences. Health-related quality of life will be assessed using the EQ-5D-3L questionnaire. Resources use and costs associated with Chagas disease will be investigated using information from the databases of the Hospital Clínic of Barcelona.
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Affiliation(s)
- Francesco Ramponi
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Céline Aerts
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Paula Sartor
- Región Sanitaria 5, Ministerio de Salud del Chaco, Juan José Castelli, Chaco, Argentina; Universidad Nacional del Nordeste, Facultad de Ciencias Exactas Naturales y Agrimensura, Corrientes Capital, Argentina
| | | | - Héctor Freilij
- Hospital de Niños Ricardo Gutiérrez, Buenos Aires, Argentina
| | - Carlos A Guzmán
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Emilio Malchiodi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología, and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología, and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Elisa Sicuri
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain; LSE Health, London School of Economics & Political Science, London, United Kingdom.
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Cai CW, O’Shea A, Eickhoff CS, Guo H, Lewis WG, Beverley SM, Hoft DF. Use of Leishmania major parasites expressing a recombinant Trypanosoma cruzi antigen as live vaccines against Chagas disease. Front Microbiol 2022; 13:1059115. [PMID: 36523834 PMCID: PMC9745109 DOI: 10.3389/fmicb.2022.1059115] [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: 09/30/2022] [Accepted: 11/07/2022] [Indexed: 12/03/2022] Open
Abstract
Introduction Trypanosoma cruzi is the protozoan parasite causing Chagas disease, a Neglected Tropical Disease that affects 8 million people and causes 12,000 deaths per year, primarily because of cardiac pathology. Effective vaccination for T. cruzi remains an elusive goal. The use of a live vaccine vector, especially one that mimics the pathogen target, may be superior to the use of recombinant protein or DNA vaccine formulations. Methods We generated recombinant Leishmania major, a related trypanosomatid parasite, as a vaccine vehicle to express the immunogenic T. cruzi trans-sialidase (TS) antigen. The induction of T cell and antibody responses, as well as T. cruzi protective immunity generated by these vaccines were assessed in vivo. Results We demonstrate that mice inoculated with these recombinant TS-expressing L. major parasites mount T cell and antibody responses directed against TS and are protected against future T. cruzi infection. We also show that the partially attenuated dhfr-ts- CC1 L. major strain, previously found to induce protective immunity to virulent L. major infection without causing pathology, can also be engineered to express the TS antigen. This latter recombinant may represent a safe and effective option to explore for ultimate use in humans. Discussion Altogether, these data indicate that L. major can stably express a T. cruzi antigen and induce T. cruzi-specific protective immunity, warranting further investigation of attenuated Leishmania parasites as vaccine.
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Affiliation(s)
- Catherine W. Cai
- Department of Molecular Microbiology & Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States,Division of Infectious Diseases, Allergy and Immunology, Department of Internal Medicine, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Anne O’Shea
- Division of Infectious Diseases, Allergy and Immunology, Department of Internal Medicine, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Christopher S. Eickhoff
- Division of Infectious Diseases, Allergy and Immunology, Department of Internal Medicine, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Hongjie Guo
- Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, Saint Louis, MO, United States
| | - Warren G. Lewis
- Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, Saint Louis, MO, United States
| | - Stephen M. Beverley
- Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, Saint Louis, MO, United States
| | - Daniel F. Hoft
- Department of Molecular Microbiology & Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States,Division of Infectious Diseases, Allergy and Immunology, Department of Internal Medicine, Saint Louis University School of Medicine, Saint Louis, MO, United States,*Correspondence: Daniel F. Hoft,
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4
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Weltz J, Volfovsky A, Laber EB. Reinforcement Learning Methods in Public Health. Clin Ther 2022; 44:139-154. [DOI: 10.1016/j.clinthera.2021.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 02/03/2023]
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5
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Th17 Cells Provide Mucosal Protection against Gastric Trypanosoma cruzi Infection. Infect Immun 2021; 89:e0073820. [PMID: 33941576 DOI: 10.1128/iai.00738-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma cruzi is the intracellular parasite of Chagas disease, a chronic condition characterized by cardiac and gastrointestinal morbidity. Protective immunity requires CD4+ T cells, and Th1 cells and gamma interferon (IFN-γ) are important players in host defense. More recently, Th17 cells and interleukin 17A (IL-17A) have been shown to exert protective functions in systemic T. cruzi infection. However, it remains unclear whether Th17 cells and IL-17A protect in the mucosa, the initial site of parasite invasion in many human cases. We found that IL-17RA knockout (KO) mice are highly susceptible to orogastric infection, indicating an important function for this cytokine in mucosal immunity to T. cruzi. To investigate the specific role of Th17 cells for mucosal immunity, we reconstituted RAG1 KO mice with T. cruzi-specific T cell receptor transgenic Th17 cells prior to orogastric T. cruzi challenges. We found that Th17 cells provided protection against gastric mucosal T. cruzi infection, indicated by significantly lower stomach parasite burdens. In vitro macrophage infection assays revealed that protection by Th17 cells is reduced with IL-17A neutralization or reversed by loss of macrophage NADPH oxidase activity. Consistently with this, mice lacking functional NADPH oxidase were not protected by Th17 cell transfer. These data are the first report that Th17 cells protect against mucosal T. cruzi infection and identify a novel protective mechanism involving the induction of NADPH oxidase activity by IL-17A. These studies provide important insights for Chagas vaccine development and, more broadly, increase our understanding of the diverse roles of Th17 cells in host defense.
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6
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Athie TS, Nascimento GC, Labis da Costa MJ, Sales Silva JD, Reis EA, Martin AP, Godman B, Dias Godói IP. Consumer willingness to pay for a hypothetical Chagas disease vaccine in Brazil: a cross-sectional study and the implications. J Comp Eff Res 2021; 10:659-672. [PMID: 33851872 DOI: 10.2217/cer-2020-0241] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Aim: Chagas disease is a serious public health problem, endemic in 21 countries in Latin America. A future vaccine can contribute to decreasing the number of cases and its complications. Methods: A cross-sectional study was conducted with residents of the northern region of Brazil, on the willingness to pay for a hypothetical vaccine against Chagas disease (effective protection of 80%). Results: We interviewed 619 individuals and seven were excluded from the analysis and the value of willingness to pay was US$23.77 (100.00 BRL). Conclusion: The Northern region of Brazil is one of the largest markets for this vaccine, due to its epidemiological relevance, so economic studies with this vaccine will be important to assist in the assessment of technologies.
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Affiliation(s)
- Thannuse Silva Athie
- Institute of Health & Biological Studies - Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
| | - Gesiane Cavalcante Nascimento
- Institute of Health & Biological Studies - Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
| | - Maria José Labis da Costa
- Institute of Health & Biological Studies - Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
| | - Juliana de Sales Silva
- Institute of Studies in Agricultural & Regional Development - Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
| | - Edna Afonso Reis
- Department of Statistics, Exact Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,Researcher of the Group (CNPq) for Epidemiological, Economic & Pharmacological Studies of Arboviruses (EEPIFARBO), Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
| | - Antony Paul Martin
- Faculty of Health & Life Sciences, Brownlow Hill, Liverpool, L69 3BX, UK.,QC Medica, York, North Yorkshire, YO23 2BD, UK
| | - Brian Godman
- Department of Pharmacoepidemiology, Institute of Pharmacy & Biomedical Sciences, 161 Cathedral Street, Glasgow G4 0RE, UK.,Division of Clinical Pharmacology, Karolinska Institute, Karolinska University Hospital, Stockholm SE-141 86, Sweden.,Department of Public Health & Pharmacy Management, School of Pharmacy, Sefako Health Sciences University, Pretoria, South Africa
| | - Isabella Piassi Dias Godói
- Institute of Health & Biological Studies - Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil.,Researcher of the Group (CNPq) for Epidemiological, Economic & Pharmacological Studies of Arboviruses (EEPIFARBO), Universidade Federal do Sul e Sudeste do Pará, Avenida dos Ipês, s/n, Cidade Universitária, Cidade Jardim, Marabá, Pará, Brazil
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7
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Omolabi KF, Odeniran PO, Olotu FA, S Soliman ME. A Mechanistic Probe into the Dual Inhibition of T. cruzi Glucokinase and Hexokinase in Chagas Disease Treatment - A Stone Killing Two Birds? Chem Biodivers 2021; 18:e2000863. [PMID: 33411971 DOI: 10.1002/cbdv.202000863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 01/07/2021] [Indexed: 01/15/2023]
Abstract
Glucokinase (GLK) and Hexokinase (HK) have been characterized as essential targets in Trypanosoma cruzi (Tc)-mediated infection. A recent study reported the propensity of the concomitant inhibition of TcGLK and TcHK by compounds GLK2-003 and GLK2-004, thereby presenting an efficient approach in Chagas disease treatment. We investigated this possibility using atomic and molecular scaling methods. Sequence alignment of TcGLK and TcHK revealed that both proteins shared approximately 33.3 % homology in their glucose/inhibitor binding sites. The total binding free energies of GLK2-003 and GLK2-004 were favorable in both proteins. PRO92 and THR185 were pivotal to the binding and stabilization of the ligands in TcGLK, likewise their conserved counterparts, PRO163 and THR237 in TcHK. Both compounds also induced a similar pattern of perturbations in both TcGLK and TcHK secondary structure. Findings from this study therefore provide insights into the underlying mechanisms of dual inhibition exhibited by the compounds. These results can pave way to discover and optimize novel dual Tc inhibitors with favorable pharmacokinetics properties eventuating in the mitigation of Chagas disease.
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Affiliation(s)
- Kehinde F Omolabi
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
| | - Paul O Odeniran
- Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, 200001, Nigeria
| | - Fisayo A Olotu
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
| | - Mahmoud E S Soliman
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
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8
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Carta A, Conversano C. On the Use of Markov Models in Pharmacoeconomics: Pros and Cons and Implications for Policy Makers. Front Public Health 2020; 8:569500. [PMID: 33194969 PMCID: PMC7661756 DOI: 10.3389/fpubh.2020.569500] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 10/06/2020] [Indexed: 11/18/2022] Open
Abstract
We present an overview of the main methodological features and the goals of pharmacoeconomic models that are classified in three major categories: regression models, decision trees, and Markov models. In particular, we focus on Markov models and define a semi-Markov model on the cost utility of a vaccine for Dengue fever discussing the key components of the model and the interpretation of its results. Next, we identify some criticalities of the decision rule arising from a possible incorrect interpretation of the model outcomes. Specifically, we focus on the difference between median and mean ICER and on handling the willingness-to-pay thresholds. We also show that the life span of the model and an incorrect hypothesis specification can lead to very different outcomes. Finally, we analyse the limit of Markov model when a large number of states is considered and focus on the implementation of tools that can bypass the lack of memory condition of Markov models. We conclude that decision makers should interpret the results of these models with extreme caution before deciding to fund any health care policy and give some recommendations about the appropriate use of these models.
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Affiliation(s)
- Andrea Carta
- Department of Business and Economics, University of Cagliari, Cagliari, Italy
| | - Claudio Conversano
- Department of Business and Economics, University of Cagliari, Cagliari, Italy
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9
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Villanueva-Lizama LE, Cruz-Chan JV, Versteeg L, Teh-Poot CF, Hoffman K, Kendricks A, Keegan B, Pollet J, Gusovsky F, Hotez PJ, Bottazzi ME, Jones KM. TLR4 agonist protects against Trypanosoma cruzi acute lethal infection by decreasing cardiac parasite burdens. Parasite Immunol 2020; 42:e12769. [PMID: 32592180 DOI: 10.1111/pim.12769] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 01/11/2023]
Abstract
E6020 is a synthetic agonist of Toll-like receptor-4 (TLR4). The purpose of this study was to evaluate the effect of different doses of E6020-SE on Trypanosoma cruzi-specific immune responses and its ability to confer protection against acute lethal infection in mice. Forty female BALB/c were infected with 500 trypomastigotes of T cruzi H1 strain, divided into four groups (n = 10) and treated at 7- and 14-day post-infection (dpi) with different doses of E6020-SE or PBS (control). Survival was followed for 51 days, mice were euthanized and hearts were collected to evaluate parasite burden, inflammation and fibrosis. We found significantly higher survival and lower parasite burdens in mice injected with E6020-SE at all doses compared to the control group. However, E6020-SE treatment did not significantly reduce cardiac inflammation or fibrosis. On the other hand, E6020-SE modulated Th1 and Th2 cytokines, decreasing IFN-γ and IL-4 in a dose-dependent manner after stimulation with parasite antigens. We conclude that E6020-SE alone increased survival by decreasing cardiac parasite burdens in BALB/c mice acutely infected with T cruzi but failed to prevent cardiac damage. Our results suggest that for optimal protection, a vaccine antigen is necessary to balance and orient a protective immune response.
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Affiliation(s)
- Liliana E Villanueva-Lizama
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA.,Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, México
| | - Julio V Cruz-Chan
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA.,Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, México
| | - Leroy Versteeg
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA.,Cell Biology and Immunology Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Christian F Teh-Poot
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, México
| | - Kristyn Hoffman
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA
| | - April Kendricks
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA
| | - Brian Keegan
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA
| | - Jeroen Pollet
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA
| | | | - Peter J Hotez
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, 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 at Texas A&M University, College Station, TX, USA
| | - Maria Elena Bottazzi
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA.,Department of Biology, Baylor University, Waco, TX, USA
| | - Kathryn M Jones
- Department of Pediatrics and National School of Tropical Medicine, Texas Children's Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, TX, USA
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10
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Dumonteil E, Herrera C, Tu W, Goff K, Fahlberg M, Haupt E, Kaur A, Marx PA, Ortega-Lopez J, Hotez PJ, Bottazzi ME. Safety and immunogenicity of a recombinant vaccine against Trypanosoma cruzi in Rhesus macaques. Vaccine 2020; 38:4584-4591. [PMID: 32417142 DOI: 10.1016/j.vaccine.2020.05.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 04/21/2020] [Accepted: 05/05/2020] [Indexed: 11/30/2022]
Abstract
Chagas disease, caused by the protozoan parasite Trypanosoma cruzi is one of the most important neglected parasitic diseases in the Americas. Vaccines represent an attractive complementary strategy for the control of T. cruzi infection and pre-clinical studies in mice demonstrated that trypomastigote surface antigen (TSA-1) and the flagellar calcium-binding (Tc24) parasite antigens are promising candidates for vaccine development. We performed here the first evaluation of the safety and immunogenicity of two recombinant vaccine antigens (named TSA1-C4 and Tc24-C4) in naïve non-human primates. Three rhesus macaques received 3 doses of each recombinant protein, formulated with E6020 (Eisai Co., Ltd.), a novel Toll-like receptor-4 agonist, in a stable emulsion. All parameters from blood chemistry and blood cell counts were stable over the course of the study and unaffected by the vaccine. A specific IgG response against both antigens was detectable after the first vaccine dose, and increased with the second dose. After three vaccine doses, stimulation of PBMCs with a peptide pool derived from TSA1-C4 resulted in the induction of TSA1-C4-specific TNFα-, IL-2- and IFNγ-producing CD4+ in one or two animals while stimulation with a peptide pool derived from Tc24-C4 only activated IFNγ-producing CD4+T cells in one animal. In two animals there was also activation of TSA1-C4-specific IL2-producing CD8+ T cells. This is the first report of the immunogenicity of T. cruzi-derived recombinant antigens formulated as an emulsion with a TLR4 agonist in a non-human primate model. Our results strongly support the need for further evaluation of the preventive efficacy of this type of vaccine in non-human primates and explore the effect of the vaccine in a therapeutic model of naturally-infected Chagasic non-human primates, which would strengthen the rationale for the clinical development as a human vaccine against Chagas disease.
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Affiliation(s)
- Eric Dumonteil
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, and Vector-Borne and Infectious Disease Research Center, Tulane University, New Orleans, LA, USA.
| | - Claudia Herrera
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, and Vector-Borne and Infectious Disease Research Center, Tulane University, New Orleans, LA, USA
| | - Weihong Tu
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, and Vector-Borne and Infectious Disease Research Center, Tulane University, New Orleans, LA, USA
| | - Kelly Goff
- Division of Microbiology, Tulane National Primate Research Center, Tulane University, Covington, LA, USA
| | - Marissa Fahlberg
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, USA
| | - Erin Haupt
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, USA
| | - Amitinder Kaur
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, USA
| | - Preston A Marx
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, and Vector-Borne and Infectious Disease Research Center, Tulane University, New Orleans, LA, USA; Division of Microbiology, Tulane National Primate Research Center, Tulane University, Covington, LA, USA
| | - Jaime Ortega-Lopez
- Departmento de Biotecnología y Bioingeniería, CINVESTAV, Mexico, D.F., Mexico
| | - Peter J Hotez
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Maria Elena Bottazzi
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
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11
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Bivona AE, Alberti AS, Cerny N, Trinitario SN, Malchiodi EL. Chagas disease vaccine design: the search for an efficient Trypanosoma cruzi immune-mediated control. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165658. [PMID: 31904415 DOI: 10.1016/j.bbadis.2019.165658] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 12/20/2019] [Indexed: 12/21/2022]
Abstract
Chagas disease is currently endemic to 21 Latin-American countries and has also become a global concern because of globalization and mass migration of chronically infected individuals. Prophylactic and therapeutic vaccination might contribute to control the infection and the pathology, as complement of other strategies such as vector control and chemotherapy. Ideal prophylactic vaccine would produce sterilizing immunity; however, a reduction of the parasite burden would prevent progression from Trypanosoma cruzi infection to Chagas disease. A therapeutic vaccine for Chagas disease may improve or even replace the treatment with current drugs which have several side effects and require long term treatment that frequently leads to therapeutic withdrawal. Here, we will review some aspects about sub-unit vaccines, the rationale behind the selection of the immunogen, the role of adjuvants, the advantages and limitations of DNA-based vaccines and the idea of therapeutic vaccines. One of the main limitations to advance vaccine development against Chagas disease is the high number of variables that must be considered and the lack of uniform criteria among research laboratories. To make possible comparisons, much of this review will be focused on experiments that kept many variables constant including antigen mass/doses, type of eukaryotic plasmid, DNA-delivery system, mice strain and sex, lethal and sublethal model of infection, and similar immunogenicity and efficacy assessments.
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Affiliation(s)
- Augusto E Bivona
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Andrés Sánchez Alberti
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Natacha Cerny
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Sebastián N Trinitario
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Emilio L Malchiodi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina.
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12
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Paes MC, Saraiva FMS, Nogueira NP, Vieira CSD, Dias FA, Rossini A, Coelho VL, Pane A, Sang F, Alcocer M. Gene expression profiling of Trypanosoma cruzi in the presence of heme points to glycosomal metabolic adaptation of epimastigotes inside the vector. PLoS Negl Trop Dis 2020; 14:e0007945. [PMID: 31895927 PMCID: PMC6959606 DOI: 10.1371/journal.pntd.0007945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 01/14/2020] [Accepted: 11/22/2019] [Indexed: 11/18/2022] Open
Abstract
Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi, and is transmitted by triatomine insects during its blood meal. Proliferative epimastigotes forms thrive inside the insects in the presence of heme (iron protoporphyrin IX), an abundant product of blood digestion, however little is known about the metabolic outcome of this signaling molecule in the parasite. Trypanosomatids exhibit unusual gene transcription employing a polycistronic transcription mechanism through trans-splicing that regulates its life cycle. Using the Deep Seq transcriptome sequencing we characterized the heme induced transcriptome of epimastigotes and determined that most of the upregulated genes were related to glucose metabolism inside the glycosomes. These results were supported by the upregulation of glycosomal isoforms of PEPCK and fumarate reductase of heme-treated parasites, implying that the fermentation process was favored. Moreover, the downregulation of mitochondrial gene enzymes in the presence of heme also supported the hypothesis that heme shifts the parasite glycosomal glucose metabolism towards aerobic fermentation. These results are examples of the environmental metabolic plasticity inside the vector supporting ATP production, promoting epimastigotes proliferation and survival.
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Affiliation(s)
- Marcia C. Paes
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
- * E-mail: (MCP); (MA)
| | - Francis M. S. Saraiva
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
| | - Natália P. Nogueira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
| | - Carolina S. D. Vieira
- Laboratório de Interação Tripanossomatídeos e Vetores—Departamento de Bioquímica, IBRAG–UERJ–Rio de Janeiro, Brazil
| | - Felipe A. Dias
- Instituto Nacional de Ciência e Tecnologia—Entomologia Molecular (INCT-EM)–Brazil
- Laboratório de Bioquímica de Artrópodes Hematófagos, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Rossini
- Laboratório de Toxicologia e Biologia Molecular, Departamento de Bioquímica, IBRAG- UERJ- Rio de Janeiro, Brazil
| | - Vitor Lima Coelho
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Attilio Pane
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fei Sang
- Deep Seq, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Marcos Alcocer
- School of Biosciences, University of Nottingham, United Kingdom
- * E-mail: (MCP); (MA)
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13
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Rios LE, Vázquez-Chagoyán JC, Pacheco AO, Zago MP, Garg NJ. Immunity and vaccine development efforts against Trypanosoma cruzi. Acta Trop 2019; 200:105168. [PMID: 31513763 PMCID: PMC7409534 DOI: 10.1016/j.actatropica.2019.105168] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 08/27/2019] [Accepted: 09/07/2019] [Indexed: 12/28/2022]
Abstract
Trypanosoma cruzi (T. cruzi) is the causative agent for Chagas disease (CD). There is a critical lack of methods for prevention of infection or treatment of acute infection and chronic disease. Studies in experimental models have suggested that the protective immunity against T. cruzi infection requires the elicitation of Th1 cytokines, lytic antibodies and the concerted activities of macrophages, T helper cells, and cytotoxic T lymphocytes (CTLs). In this review, we summarize the research efforts in vaccine development to date and the challenges faced in achieving an efficient prophylactic or therapeutic vaccine against human CD.
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Affiliation(s)
- Lizette E Rios
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555-1070, USA
| | - Juan Carlos Vázquez-Chagoyán
- Centro de Investigación y Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Toluca, México
| | - Antonio Ortega Pacheco
- Departamento de Salud Animal y Medicina Preventiva, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México
| | - M Paola Zago
- Instituto de Patología Experimental, Universidad Nacional de Salta - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Salta, Argentina
| | - Nisha J Garg
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555-1070, USA; Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX.
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14
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Michel-Todó L, Reche PA, Bigey P, Pinazo MJ, Gascón J, Alonso-Padilla J. In silico Design of an Epitope-Based Vaccine Ensemble for Chagas Disease. Front Immunol 2019; 10:2698. [PMID: 31824493 PMCID: PMC6882931 DOI: 10.3389/fimmu.2019.02698] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 11/01/2019] [Indexed: 01/21/2023] Open
Abstract
Trypanosoma cruzi infection causes Chagas disease, which affects 7 million people worldwide. Two drugs are available to treat it: benznidazole and nifurtimox. Although both are efficacious against the acute stage of the disease, this is usually asymptomatic and goes undiagnosed and untreated. Diagnosis is achieved at the chronic stage, when life-threatening heart and/or gut tissue disruptions occur in ~30% of those chronically infected. By then, the drugs' efficacy is reduced, but not their associated high toxicity. Given current deficiencies in diagnosis and treatment, a vaccine to prevent infection and/or the development of symptoms would be a breakthrough in the management of the disease. Current vaccine candidates are mostly based on the delivery of single antigens or a few different antigens. Nevertheless, due to the high biological complexity of the parasite, targeting as many antigens as possible would be desirable. In this regard, an epitope-based vaccine design could be a well-suited approach. With this aim, we have gone through publicly available databases to identify T. cruzi epitopes from several antigens. By means of a computer-aided strategy, we have prioritized a set of epitopes based on sequence conservation criteria, projected population coverage of Latin American population, and biological features of their antigens of origin. Fruit of this analysis, we provide a selection of CD8+ T cell, CD4+ T cell, and B cell epitopes that have <70% identity to human or human microbiome protein sequences and represent the basis toward the development of an epitope-based vaccine against T. cruzi.
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Affiliation(s)
- Lucas Michel-Todó
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic, University of Barcelona, Barcelona, Spain
| | - Pedro Antonio Reche
- Laboratory of Immunomedicine, Faculty of Medicine, University Complutense of Madrid, Madrid, Spain
| | - Pascal Bigey
- Université de Paris, UTCBS, CNRS, INSERM, Paris, France.,PSL University, ChimieParisTech, Paris, France
| | - Maria-Jesus Pinazo
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic, University of Barcelona, Barcelona, Spain
| | - Joaquim Gascón
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic, University of Barcelona, Barcelona, Spain
| | - Julio Alonso-Padilla
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic, University of Barcelona, Barcelona, Spain
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15
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Bartsch SM, Bottazzi ME, Asti L, Strych U, Meymandi S, Falcón-Lezama JA, Randall S, Hotez PJ, Lee BY. Economic value of a therapeutic Chagas vaccine for indeterminate and Chagasic cardiomyopathy patients. Vaccine 2019; 37:3704-3714. [PMID: 31104883 DOI: 10.1016/j.vaccine.2019.05.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 05/06/2019] [Accepted: 05/09/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Therapeutic vaccines to prevent Chagas disease progression to cardiomyopathy are under development because the only available medications (benznidazole and nifurtimox) are limited by their efficacy, long treatment course, and side effects. Better understanding the potential clinical and economic value of such vaccines can help guide development and implementation. METHODS We developed a computational Chagas Markov model to evaluate the clinical and economic value of a therapeutic vaccine given in conjunction with benznidazole in indeterminate and chronic Chagas patients. Scenarios explored the vaccine's impact on reducing drug treatment dosage, duration, and adverse events, and risk of disease progression. RESULTS When administering standard-of-care benznidazole to 1000 indeterminate patients, 148 discontinued treatment and 219 progressed to chronic disease, resulting in 119 Chagas-related deaths and 2293 DALYs, costing $18.9 million in lifetime societal costs. Compared to benznidazole-only, therapeutic vaccination administered with benznidazole (25-75% reduction in standard dose and duration), resulted in 37-111 more patients (of 1000) completing treatment, preventing 11-219 patients from progressing, 6-120 deaths, and 108-2229 DALYs (5-100% progression risk reduction), saving ≤$16,171 per patient. When vaccinating determinate Kuschnir class 1 Chagas patients, 10-197 fewer patients further progressed compared to benznidazole-only, averting 11-228 deaths and 144-3037 DALYs (5-100% progression risk reduction), saving ≤$34,059 per person. When vaccinating Kuschnir class 2 patients, 13-279 fewer progressed (279 with benznidazole-only), averting 13-692 deaths and 283-10,785 DALYs (5-100% progression risk reduction), saving ≤$89,759. Therapeutic vaccination was dominant (saved costs and provided health benefits) with ≥ 5% progression risk reduction, except when only reducing drug treatment regimen and adverse events, but remained cost-effective when costing <$200. CONCLUSIONS Our study helps outline the thresholds at which a therapeutic Chagas vaccine may be cost-effective (e.g., <5% reduction in preventing cardiac progression, 25% reduction in benznidazole treatment doses and duration) and cost-saving (e.g., ≥5% and 25%, respectively).
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Affiliation(s)
- Sarah M Bartsch
- Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center (GOPC), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Maria Elena Bottazzi
- National School of Tropical Medicine and Departments of Pediatrics and Molecular Virology & Microbiology, Baylor College of Medicine, One Baylor Plaza, BCM113 Houston, TX 77030, USA
| | - Lindsey Asti
- Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center (GOPC), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Ulrich Strych
- National School of Tropical Medicine and Departments of Pediatrics and Molecular Virology & Microbiology, Baylor College of Medicine, One Baylor Plaza, BCM113 Houston, TX 77030, USA
| | - Sheba Meymandi
- Center of Excellence for Chagas Disease at Olive View-UCLA Medical Center, 14445 Olive View Drive, Sylmar, CA 91342, USA
| | - Jorge Abelardo Falcón-Lezama
- Carlos Slim Foundation, Lago Zurich 245, Piso 20. Ampliación Granada, Del. Miguel Hidalgo, C.P. 11529 Ciudad de México, Mexico
| | - Samuel Randall
- Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center (GOPC), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Peter J Hotez
- National School of Tropical Medicine and Departments of Pediatrics and Molecular Virology & Microbiology, Baylor College of Medicine, One Baylor Plaza, BCM113 Houston, TX 77030, USA
| | - Bruce Y Lee
- Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center (GOPC), Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA.
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16
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de la Cruz JJ, Villanueva-Lizama L, Dzul-Huchim V, Ramírez-Sierra MJ, Martinez-Vega P, Rosado-Vallado M, Ortega-Lopez J, Flores-Pucheta CI, Gillespie P, Zhan B, Bottazzi ME, Hotez PJ, Dumonteil E. Production of recombinant TSA-1 and evaluation of its potential for the immuno-therapeutic control of Trypanosoma cruzi infection in mice. Hum Vaccin Immunother 2018; 15:210-219. [PMID: 30192702 PMCID: PMC6363145 DOI: 10.1080/21645515.2018.1520581] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A therapeutic vaccine for human Chagas disease (American trypanosomiasis caused by Trypanosoma cruzi) is under development based on the success of vaccinating mice with DNA constructs expressing the antigens Tc24 and Tc-TSA-1. However, because DNA and nucleic acid vaccines produce less than optimal responses in humans, our strategy relies on administering a recombinant protein-based vaccine, together with adjuvants that promote Th1-type immunity. Here we describe a process for the purification and refolding of recombinant TSA-1 expressed in Escherichia coli. The overall yield (20–25%) and endotoxin level of the purified recombinant TSA-1 (rTSA-1) is suitable for pilot scale production of the antigen for use in phase 1 clinical trials. Mice infected with T. cruzi were treated with rTSA-1, either alone or with Toll-like receptor 4 (TLR-4) agonist adjuvants including monophosphoryl lipid A (MPLA), glucopyranosyl lipid A (GLA, IDRI), and E6020 (EISEI, Inc). TSA-1 with the TLR-4 agonists was effective at reducing parasitemia relative to rTSA-1 alone, although it was difficult to discern a therapeutic effect compared to treatment with TLR-4 agonists alone. However, rTSA-1 with a 10 ug dose of MPLA optimized reductions in cardiac tissue inflammation, which were significantly reduced compared to MPLA alone. It also elicited the lowest parasite burden and the highest levels of TSA-1-specific IFN-gamma levels and IFN-gamma/IL-4 ratios. These results warrant the further evaluation of rTSA-1 in combination with rTc24 in order to maximize the therapeutic effect of vaccine-linked chemotherapy in both mice and non-human primates before advancing to clinical development.
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Affiliation(s)
- Juan Jose de la Cruz
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - Liliana Villanueva-Lizama
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - Victor Dzul-Huchim
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - María-Jesus Ramírez-Sierra
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - Pedro Martinez-Vega
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - Miguel Rosado-Vallado
- a Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi , Universidad Autónoma de Yucatán , Mérida , Yucatán , México
| | - Jaime Ortega-Lopez
- b Departamento de Biotecnología y Bioingeniería , CINVESTAV-IPN , Ciudad de México , México
| | | | - Portia Gillespie
- c Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and Molecular Virology and Microbiology , National School of Tropical Medicine, Baylor College of Medicine , Houston , TX , USA
| | - Bin Zhan
- c Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and Molecular Virology and Microbiology , National School of Tropical Medicine, Baylor College of Medicine , Houston , TX , USA
| | - Maria Elena Bottazzi
- c Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and Molecular Virology and Microbiology , National School of Tropical Medicine, Baylor College of Medicine , Houston , TX , USA
| | - Peter J Hotez
- c Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and Molecular Virology and Microbiology , National School of Tropical Medicine, Baylor College of Medicine , Houston , TX , USA
| | - Eric Dumonteil
- d Department of Tropical Medicine , Vector-Borne and Infectious Disease Research Center, School of Public Health and Tropical Medicine, Tulane University , New Orleans , LA , USA
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17
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Vaccine-Linked Chemotherapy Improves Benznidazole Efficacy for Acute Chagas Disease. Infect Immun 2018; 86:IAI.00876-17. [PMID: 29311242 DOI: 10.1128/iai.00876-17] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 01/02/2018] [Indexed: 12/14/2022] Open
Abstract
Chagas disease affects 6 to 7 million people worldwide, resulting in significant disease burdens and health care costs in countries of endemicity. Chemotherapeutic treatment is restricted to two parasiticidal drugs, benznidazole and nifurtimox. Both drugs are highly effective during acute disease but are only minimally effective during chronic disease and fraught with significant adverse clinical effects. In experimental models, vaccines can be used to induce parasite-specific balanced TH1/TH2 immune responses that effectively reduce parasite burdens and associated inflammation while minimizing adverse effects. The objective of this study was to determine the feasibility of vaccine-linked chemotherapy for reducing the amount of benznidazole required to significantly reduce blood and tissue parasite burdens. In this study, we were able to achieve a 4-fold reduction in the amount of benznidazole required to significantly reduce blood and tissue parasite burdens by combining the low-dose benznidazole with a recombinant vaccine candidate, Tc24 C4, formulated with a synthetic Toll-like 4 receptor agonist, E6020, in a squalene oil-in-water emulsion. Additionally, vaccination induced a robust parasite-specific balanced TH1/TH2 immune response. We concluded that vaccine-linked chemotherapy is a feasible option for advancement to clinical use for improving the tolerability and efficacy of benznidazole.
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18
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Bontempi I, Fleitas P, Poato A, Vicco M, Rodeles L, Prochetto E, Cabrera G, Beluzzo B, Arias D, Racca A, Guerrero S, Marcipar I. Trans-sialidase overcomes many antigens to be used as a vaccine candidate against Trypanosoma cruzi. Immunotherapy 2018; 9:555-565. [PMID: 28595515 DOI: 10.2217/imt-2017-0009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
AIM The development of vaccines against Trypanosoma cruzi remains in an exploratory stage. Despite several antigen candidates have been evaluated, a comparison among the performance of the immunogens cannot be carried out because the available reports differ in formulations and infection model. In this work, we compared the protective capacity of seven T. cruzi antigens in the same model of five new antigens and two well-established candidates. Materials & methods: We evaluated highly immunogenic proteins that contain tandem repeats (FRA [flagelar repetitive protein], Tc3, Tc6); enzymes involved in metabolic pathways critical for parasite survival (cytosolic tryparedoxin peroxidase and tryparedoxin peroxidase); and enzymes involved in parasite invasion (trans-sialidase [TS] and cruzipain). All these antigens were formulated with Freund's adjuvant and protection against the parasite infection was assessed in BALB/c mice. RESULTS Tc3, cytosolic tryparedoxin peroxidase, cruzipain and TS showed the best outcome after infection in survival level and parasitemia. According to these data, these groups were also assessed using the ISCOMATRIX™ adjuvant which is being used in clinical trials. CONCLUSION Taken together, our results showed that the TS overcomes the performance of other antigens when the same model is employed, confirming that TS is a promising antigen that could be used as a vaccine against T. cruzi.
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Affiliation(s)
- Ivan Bontempi
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Pedro Fleitas
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Alexia Poato
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Miguel Vicco
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina.,Facultad de Ciencias Médicas, Universidad Nacional del Litoral, Argentina
| | - Luz Rodeles
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina.,Facultad de Ciencias Médicas, Universidad Nacional del Litoral, Argentina
| | - Estefania Prochetto
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Gabriel Cabrera
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Bruno Beluzzo
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Diego Arias
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Argentina
| | - Andrea Racca
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
| | - Sergio Guerrero
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Argentina
| | - Iván Marcipar
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Argentina
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19
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Lee BY, Bartsch SM, Skrip L, Hertenstein DL, Avelis CM, Ndeffo-Mbah M, Tilchin C, Dumonteil EO, Galvani A. Are the London Declaration's 2020 goals sufficient to control Chagas disease?: Modeling scenarios for the Yucatan Peninsula. PLoS Negl Trop Dis 2018; 12:e0006337. [PMID: 29554086 PMCID: PMC5875875 DOI: 10.1371/journal.pntd.0006337] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 03/29/2018] [Accepted: 02/22/2018] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND The 2020 Sustainable Development goals call for 100% certified interruption or control of the three main forms of Chagas disease transmission in Latin America. However, how much will achieving these goals to varying degrees control Chagas disease; what is the potential impact of missing these goals and if they are achieved, what may be left? METHODS We developed a compartmental simulation model that represents the triatomine, human host, and non-human host populations and vector-borne, congenital, and transfusional T. cruzi transmission between them in the domestic and peridomestic settings to evaluate the impact of limiting transmission in a 2,000 person virtual village in Yucatan, Mexico. RESULTS Interruption of domestic vectorial transmission had the largest impact on T. cruzi transmission and prevalence in all populations. Most of the gains were achieved within the first few years. Controlling vectorial transmission resulted in a 46.1-83.0% relative reduction in the number of new acute Chagas cases for a 50-100% interruption in domestic vector-host contact. Only controlling congenital transmission led to a 2.4-8.1% (30-100% interruption) relative reduction in the total number of new acute cases and reducing only transfusional transmission led to a 0.1-0.3% (30-100% reduction). Stopping all three forms of transmission resulted in 0.5 total transmission events over five years (compared to 5.0 with no interruption); interrupting all forms by 30% resulted in 3.4 events over five years per 2,000 persons. CONCLUSIONS While reducing domestic vectorial, congenital, and transfusional transmission can successfully reduce transmission to humans (up to 82% in one year), achieving the 2020 goals would still result in 0.5 new acute cases per 2,000 over five years. Even if the goals are missed, major gains can be achieved within the first few years. Interrupting transmission should be combined with other efforts such as a vaccine or improved access to care, especially for the population of already infected individuals.
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Affiliation(s)
- Bruce Y. Lee
- Public Health Computational and Operations Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- * E-mail:
| | - Sarah M. Bartsch
- Public Health Computational and Operations Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Laura Skrip
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT, United States of America
| | - Daniel L. Hertenstein
- Public Health Computational and Operations Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Cameron M. Avelis
- Public Health Computational and Operations Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Martial Ndeffo-Mbah
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT, United States of America
| | - Carla Tilchin
- Public Health Computational and Operations Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
- Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Eric O. Dumonteil
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, United States of America
| | - Alison Galvani
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT, United States of America
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20
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Lenk EJ, Redekop WK, Luyendijk M, Fitzpatrick C, Niessen L, Stolk WA, Tediosi F, Rijnsburger AJ, Bakker R, Hontelez JAC, Richardus JH, Jacobson J, Le Rutte EA, de Vlas SJ, Severens JL. Socioeconomic benefit to individuals of achieving 2020 targets for four neglected tropical diseases controlled/eliminated by innovative and intensified disease management: Human African trypanosomiasis, leprosy, visceral leishmaniasis, Chagas disease. PLoS Negl Trop Dis 2018; 12:e0006250. [PMID: 29534061 PMCID: PMC5849290 DOI: 10.1371/journal.pntd.0006250] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 01/18/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The control or elimination of neglected tropical diseases (NTDs) has targets defined by the WHO for 2020, reinforced by the 2012 London Declaration. We estimated the economic impact to individuals of meeting these targets for human African trypanosomiasis, leprosy, visceral leishmaniasis and Chagas disease, NTDs controlled or eliminated by innovative and intensified disease management (IDM). METHODS A systematic literature review identified information on productivity loss and out-of-pocket payments (OPPs) related to these NTDs, which were combined with projections of the number of people suffering from each NTD, country and year for 2011-2020 and 2021-2030. The ideal scenario in which the WHO's 2020 targets are met was compared with a counterfactual scenario that assumed the situation of 1990 stayed unaltered. Economic benefit equaled the difference between the two scenarios. Values are reported in 2005 US$, purchasing power parity-adjusted, discounted at 3% per annum from 2010. Probabilistic sensitivity analyses were used to quantify the degree of uncertainty around the base-case impact estimate. RESULTS The total global productivity gained for the four IDM-NTDs was I$ 23.1 (I$ 15.9 -I$ 34.0) billion in 2011-2020 and I$ 35.9 (I$ 25.0 -I$ 51.9) billion in 2021-2030 (2.5th and 97.5th percentiles in brackets), corresponding to US$ 10.7 billion (US$ 7.4 -US$ 15.7) and US$ 16.6 billion (US$ 11.6 -US$ 24.0). Reduction in OPPs was I$ 14 billion (US$ 6.7 billion) and I$ 18 billion (US$ 10.4 billion) for the same periods. CONCLUSIONS We faced important limitations to our work, such as finding no OPPs for leprosy. We had to combine limited data from various sources, heterogeneous background, and of variable quality. Nevertheless, based on conservative assumptions and subsequent uncertainty analyses, we estimate that the benefits of achieving the targets are considerable. Under plausible scenarios, the economic benefits far exceed the necessary investments by endemic country governments and their development partners. Given the higher frequency of NTDs among the poorest households, these investments represent good value for money in the effort to improve well-being, distribute the world's prosperity more equitably and reduce inequity.
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Affiliation(s)
- Edeltraud J. Lenk
- Erasmus School of Health Policy & Management, Erasmus University Rotterdam, Rotterdam, The Netherlands
| | - William K. Redekop
- Erasmus School of Health Policy & Management, Erasmus University Rotterdam, Rotterdam, The Netherlands
| | - Marianne Luyendijk
- Erasmus School of Health Policy & Management, Erasmus University Rotterdam, Rotterdam, The Netherlands
| | - Christopher Fitzpatrick
- Department of control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Louis Niessen
- Centre for Applied Health Research and Delivery, Department of International Public Health, Liverpool School of Tropical Medicine and University of Liverpool, Liverpool, United Kingdom
| | - Wilma A. Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Fabrizio Tediosi
- Swiss Tropical and Public Health Institute, University of Basel, Basel, Switzerland
| | | | - Roel Bakker
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jan A. C. Hontelez
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jan H. Richardus
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Julie Jacobson
- Global Health Program, Bill & Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Epke A. Le Rutte
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sake J. de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Johan L. Severens
- Erasmus School of Health Policy & Management, Erasmus University Rotterdam, Rotterdam, The Netherlands
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21
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Biter AB, Weltje S, Hudspeth EM, Seid CA, McAtee CP, Chen WH, Pollet JB, Strych U, Hotez PJ, Bottazzi ME. Characterization and Stability of Trypanosoma cruzi 24-C4 (Tc24-C4), a Candidate Antigen for a Therapeutic Vaccine Against Chagas Disease. J Pharm Sci 2017; 107:1468-1473. [PMID: 29274820 DOI: 10.1016/j.xphs.2017.12.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 11/20/2017] [Accepted: 12/12/2017] [Indexed: 12/19/2022]
Abstract
Chagas disease due to chronic infection with Trypanosoma cruzi is a neglected cause of heart disease, affecting approximately 6-10 million individuals in Latin America and elsewhere. T. cruzi Tc24, a calcium-binding protein in the flagellar pocket of the parasite, is a candidate antigen for an injectable therapeutic vaccine as an alternative or a complement to chemotherapy. Previously, we reported that a genetically engineered construct from which all cysteine residues had been eliminated (Tc24-C4) yields a recombinant protein with reduced aggregation and improved analytical purity in comparison to the wild-type form, without compromising antigenicity and immunogenicity. We now report that the established process for producing Escherichia coli-expressed Tc24-C4 protein is robust and reproducibly yields protein lots with consistent analytical characteristics, freeze-thaw, accelerated, and long-term stability profiles. The data indicate that, like most proteins, Tc24-C4 should be stable at -80°C, but also at 4°C and room temperature for at least 30 days, and up to 7-15 days at 37°C. Thus, the production process for recombinant Tc24-C4 is suitable for Current Good Manufacturing Practice production and clinical testing, based on process robustness, analytical characteristics, and stability profile.
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Affiliation(s)
- Amadeo B Biter
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Sarah Weltje
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Elissa M Hudspeth
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Christopher A Seid
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - C Patrick McAtee
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Wen-Hsiang Chen
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Jeroen B Pollet
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Ulrich Strych
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030
| | - Peter J Hotez
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030; Department of Biology, Baylor University, Waco, Texas 76706
| | - Maria Elena Bottazzi
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas 77030; Texas Children's Hospital Center for Vaccine Development, Houston, Texas 77030; Department of Biology, Baylor University, Waco, Texas 76706.
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Nogueira NP, Saraiva FMS, Oliveira MP, Mendonça APM, Inacio JDF, Almeida-Amaral EE, Menna-Barreto RF, Laranja GAT, Torres EJL, Oliveira MF, Paes MC. Heme modulates Trypanosoma cruzi bioenergetics inducing mitochondrial ROS production. Free Radic Biol Med 2017; 108:183-191. [PMID: 28363600 DOI: 10.1016/j.freeradbiomed.2017.03.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 03/20/2017] [Accepted: 03/25/2017] [Indexed: 12/27/2022]
Abstract
Trypanosoma cruzi is the causative agent of Chagas disease and has a single mitochondrion, an organelle responsible for ATP production and the main site for the formation of reactive oxygen species (ROS). T. cruzi is an obligate intracellular parasite with a complex life cycle that alternates between vertebrate and invertebrate hosts, therefore the development of survival strategies and morphogenetic adaptations to deal with the various environments is mandatory. Over the years our group has been studying the vector-parasite interactions using heme as a physiological oxidant molecule that triggered epimastigote proliferation however, the source of ROS induced by heme remained unknown. In the present study we demonstrate the involvement of heme in the parasite mitochondrial metabolism, decreasing oxygen consumption leading to increased mitochondrial ROS and membrane potential. First, we incubated epimastigotes with carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP), an uncoupler of oxidative phosphorylation, which led to decreased ROS formation and parasite proliferation, even in the presence of heme, correlating mitochondrial ROS and T. cruzi survival. This hypothesis was confirmed after the mitochondria-targeted antioxidant ((2-(2,2,6,6 Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl) triphenylphosphonium chloride (MitoTEMPO) decreased both heme-induced ROS and epimastigote proliferation. Furthermore, heme increased the percentage of tetramethylrhodamine methyl ester (TMRM) positive parasites tremendously-indicating the hyperpolarization and increase of potential of the mitochondrial membrane (ΔΨm). Assessing the mitochondrial functional metabolism, we observed that in comparison to untreated parasites, heme-treated epimastigotes decreased their oxygen consumption, and increased the complex II-III activity. These changes allowed the electron flow into the electron transport system, even though the complex IV (cytochrome c oxidase) activity decreased significantly, showing that heme-induced mitochondrial ROS appears to be a consequence of the enhanced mitochondrial physiological modulation. Finally, the parasites that were submitted to high concentrations of heme presented no alterations in the ultrastructure. Consequently, our results suggest that heme released by the insect vector after the blood meal, modify epimastigote mitochondrial physiology to increase ROS as a metabolic mechanism to maintain epimastigote survival and proliferation.
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Affiliation(s)
- Natália P Nogueira
- Laboratório de Interação de Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular (INCT-EM), Brazil
| | - Francis M S Saraiva
- Laboratório de Interação de Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, RJ, Brazil
| | - Matheus P Oliveira
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
| | - Ana Paula M Mendonça
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
| | - Job D F Inacio
- Laboratório de Bioquímica de Tripanossomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, RJ, Brazil
| | - Elmo E Almeida-Amaral
- Laboratório de Bioquímica de Tripanossomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, RJ, Brazil
| | - Rubem F Menna-Barreto
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, RJ, Brazil
| | - Gustavo A T Laranja
- Laboratório de Interação de Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, RJ, Brazil
| | - Eduardo J Lopes Torres
- Laboratório de Helmintologia Romero Lascasas Porto, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, RJ, Brazil
| | - Marcus F Oliveira
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
| | - Marcia C Paes
- Laboratório de Interação de Tripanossomatídeos e Vetores, Departamento de Bioquímica, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular (INCT-EM), Brazil
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Bradley BD, Jung T, Tandon-Verma A, Khoury B, Chan TCY, Cheng YL. Operations research in global health: a scoping review with a focus on the themes of health equity and impact. Health Res Policy Syst 2017; 15:32. [PMID: 28420381 PMCID: PMC5395767 DOI: 10.1186/s12961-017-0187-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/06/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Operations research (OR) is a discipline that uses advanced analytical methods (e.g. simulation, optimisation, decision analysis) to better understand complex systems and aid in decision-making. Herein, we present a scoping review of the use of OR to analyse issues in global health, with an emphasis on health equity and research impact. A systematic search of five databases was designed to identify relevant published literature. A global overview of 1099 studies highlights the geographic distribution of OR and common OR methods used. From this collection of literature, a narrative description of the use of OR across four main application areas of global health - health systems and operations, clinical medicine, public health and health innovation - is also presented. The theme of health equity is then explored in detail through a subset of 44 studies. Health equity is a critical element of global health that cuts across all four application areas, and is an issue particularly amenable to analysis through OR. Finally, we present seven select cases of OR analyses that have been implemented or have influenced decision-making in global health policy or practice. Based on these cases, we identify three key drivers for success in bridging the gap between OR and global health policy, namely international collaboration with stakeholders, use of contextually appropriate data, and varied communication outlets for research findings. Such cases, however, represent a very small proportion of the literature found. CONCLUSION Poor availability of representative and quality data, and a lack of collaboration between those who develop OR models and stakeholders in the contexts where OR analyses are intended to serve, were found to be common challenges for effective OR modelling in global health.
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Affiliation(s)
- Beverly D Bradley
- Centre for Global Engineering, University of Toronto, Toronto, ON, Canada. .,Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St, Toronto, ON, M5S 3E5, Canada.
| | - Tiffany Jung
- Centre for Global Engineering, University of Toronto, Toronto, ON, Canada.,Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St, Toronto, ON, M5S 3E5, Canada
| | - Ananya Tandon-Verma
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON, Canada
| | - Bassem Khoury
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON, Canada
| | - Timothy C Y Chan
- Centre for Global Engineering, University of Toronto, Toronto, ON, Canada.,Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON, Canada.,Centre for Healthcare Engineering, University of Toronto, Toronto, ON, Canada
| | - Yu-Ling Cheng
- Centre for Global Engineering, University of Toronto, Toronto, ON, Canada.,Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St, Toronto, ON, M5S 3E5, Canada
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24
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Lee BY, Mueller LE, Tilchin CG. A systems approach to vaccine decision making. Vaccine 2016; 35 Suppl 1:A36-A42. [PMID: 28017430 DOI: 10.1016/j.vaccine.2016.11.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 11/04/2016] [Accepted: 11/05/2016] [Indexed: 12/14/2022]
Abstract
Vaccines reside in a complex multiscale system that includes biological, clinical, behavioral, social, operational, environmental, and economical relationships. Not accounting for these systems when making decisions about vaccines can result in changes that have little effect rather than solutions, lead to unsustainable solutions, miss indirect (e.g., secondary, tertiary, and beyond) effects, cause unintended consequences, and lead to wasted time, effort, and resources. Mathematical and computational modeling can help better understand and address complex systems by representing all or most of the components, relationships, and processes. Such models can serve as "virtual laboratories" to examine how a system operates and test the effects of different changes within the system. Here are ten lessons learned from using computational models to bring more of a systems approach to vaccine decision making: (i) traditional single measure approaches may overlook opportunities; (ii) there is complex interplay among many vaccine, population, and disease characteristics; (iii) accounting for perspective can identify synergies; (iv) the distribution system should not be overlooked; (v) target population choice can have secondary and tertiary effects; (vi) potentially overlooked characteristics can be important; (vii) characteristics of one vaccine can affect other vaccines; (viii) the broader impact of vaccines is complex; (ix) vaccine administration extends beyond the provider level; and (x) the value of vaccines is dynamic.
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Affiliation(s)
- Bruce Y Lee
- Public Health Computational and Operations Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States.
| | - Leslie E Mueller
- Public Health Computational and Operations Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Carla G Tilchin
- Public Health Computational and Operations Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
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25
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Status of vaccine research and development of vaccines for Chagas disease. Vaccine 2016; 34:2996-3000. [DOI: 10.1016/j.vaccine.2016.03.074] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 03/09/2016] [Indexed: 12/12/2022]
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26
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Cucunubá ZM, Okuwoga O, Basáñez MG, Nouvellet P. Increased mortality attributed to Chagas disease: a systematic review and meta-analysis. Parasit Vectors 2016; 9:42. [PMID: 26813568 PMCID: PMC4728795 DOI: 10.1186/s13071-016-1315-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 01/11/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The clinical outcomes associated with Chagas disease remain poorly understood. In addition to the burden of morbidity, the burden of mortality due to Trypanosoma cruzi infection can be substantial, yet its quantification has eluded rigorous scrutiny. This is partly due to considerable heterogeneity between studies, which can influence the resulting estimates. There is a pressing need for accurate estimates of mortality due to Chagas disease that can be used to improve mathematical modelling, burden of disease evaluations, and cost-effectiveness studies. METHODS A systematic literature review was conducted to select observational studies comparing mortality in populations with and without a diagnosis of Chagas disease using the PubMed, MEDLINE, EMBASE, Web of Science and LILACS databases, without restrictions on language or date of publication. The primary outcome of interest was mortality (as all-cause mortality, sudden cardiac death, heart transplant or cardiovascular deaths). Data were analysed using a random-effects model to obtain the relative risk (RR) of mortality, the attributable risk percent (ARP), and the annual mortality rates (AMR). The statistic I(2) (proportion of variance in the meta-analysis due to study heterogeneity) was calculated. Sensitivity analyses and publication bias test were also conducted. RESULTS Twenty five studies were selected for quantitative analysis, providing data on 10,638 patients, 53,346 patient-years of follow-up, and 2739 events. Pooled estimates revealed that Chagas disease patients have significantly higher AMR compared with non-Chagas disease patients (0.18 versus 0.10; RR = 1.74, 95% CI 1.49-2.03). Substantial heterogeneity was found among studies (I(2) = 67.3%). The ARP above background mortality was 42.5%. Through a sub-analysis patients were classified by clinical group (severe, moderate, asymptomatic). While RR did not differ significantly between clinical groups, important differences in AMR were found: AMR = 0.43 in Chagas vs. 0.29 in non-Chagas patients (RR = 1.40, 95% CI 1.21-1.62) in the severe group; AMR = 0.16 (Chagas) vs. 0.08 (non-Chagas) (RR = 2.10, 95% CI 1.52-2.91) in the moderate group, and AMR = 0.02 vs. 0.01 (RR = 1.42, 95% CI 1.14-1.77) in the asymptomatic group. Meta-regression showed no evidence of study-level covariates on the effect size. Publication bias was not statistically significant (Egger's test p=0.08). CONCLUSIONS The results indicate a statistically significant excess of mortality due to Chagas disease that is shared among both symptomatic and asymptomatic populations.
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Affiliation(s)
- Zulma M Cucunubá
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, Norfolk Place, London, W2 1PG, United Kingdom. .,Grupo de Parasitología - RED CHAGAS, Instituto Nacional de Salud, Bogotá, Colombia.
| | - Omolade Okuwoga
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, Norfolk Place, London, W2 1PG, United Kingdom.
| | - María-Gloria Basáñez
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, Norfolk Place, London, W2 1PG, United Kingdom.
| | - Pierre Nouvellet
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, Norfolk Place, London, W2 1PG, United Kingdom. .,Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, UK.
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27
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Hollingsworth TD, Adams ER, Anderson RM, Atkins K, Bartsch S, Basáñez MG, Behrend M, Blok DJ, Chapman LAC, Coffeng L, Courtenay O, Crump RE, de Vlas SJ, Dobson A, Dyson L, Farkas H, Galvani AP, Gambhir M, Gurarie D, Irvine MA, Jervis S, Keeling MJ, Kelly-Hope L, King C, Lee BY, Le Rutte EA, Lietman TM, Ndeffo-Mbah M, Medley GF, Michael E, Pandey A, Peterson JK, Pinsent A, Porco TC, Richardus JH, Reimer L, Rock KS, Singh BK, Stolk W, Swaminathan S, Torr SJ, Townsend J, Truscott J, Walker M, Zoueva A. Quantitative analyses and modelling to support achievement of the 2020 goals for nine neglected tropical diseases. Parasit Vectors 2015; 8:630. [PMID: 26652272 PMCID: PMC4674954 DOI: 10.1186/s13071-015-1235-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 12/01/2015] [Indexed: 12/30/2022] Open
Abstract
Quantitative analysis and mathematical models are useful tools in informing strategies to control or eliminate disease. Currently, there is an urgent need to develop these tools to inform policy to achieve the 2020 goals for neglected tropical diseases (NTDs). In this paper we give an overview of a collection of novel model-based analyses which aim to address key questions on the dynamics of transmission and control of nine NTDs: Chagas disease, visceral leishmaniasis, human African trypanosomiasis, leprosy, soil-transmitted helminths, schistosomiasis, lymphatic filariasis, onchocerciasis and trachoma. Several common themes resonate throughout these analyses, including: the importance of epidemiological setting on the success of interventions; targeting groups who are at highest risk of infection or re-infection; and reaching populations who are not accessing interventions and may act as a reservoir for infection,. The results also highlight the challenge of maintaining elimination 'as a public health problem' when true elimination is not reached. The models elucidate the factors that may be contributing most to persistence of disease and discuss the requirements for eventually achieving true elimination, if that is possible. Overall this collection presents new analyses to inform current control initiatives. These papers form a base from which further development of the models and more rigorous validation against a variety of datasets can help to give more detailed advice. At the moment, the models' predictions are being considered as the world prepares for a final push towards control or elimination of neglected tropical diseases by 2020.
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Affiliation(s)
| | - Emily R Adams
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | | | - Katherine Atkins
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Sarah Bartsch
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | | | | | - David J Blok
- Erasmus University Medical Center, 3015 CE, Rotterdam, Netherlands
| | | | - Luc Coffeng
- Erasmus University Medical Center, 3015 CE, Rotterdam, Netherlands
| | | | - Ron E Crump
- University of Warwick, Coventry, CV4 7AL, UK
| | - Sake J de Vlas
- Erasmus University Medical Center, 3015 CE, Rotterdam, Netherlands
| | - Andy Dobson
- Princeton University, New Jersey, NJ, 08544, USA
| | | | | | | | | | - David Gurarie
- Case Western Reserve University, Cleveland, OH, 44106, USA
| | | | | | | | | | - Charles King
- Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Bruce Y Lee
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Epke A Le Rutte
- Erasmus University Medical Center, 3015 CE, Rotterdam, Netherlands
| | - Thomas M Lietman
- University of California, San Francisco, San Francisco, CA, 94143, USA
| | | | - Graham F Medley
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Edwin Michael
- University of Notre Dame, South Bend, IN, 47556, USA
| | | | | | - Amy Pinsent
- Monash University, Melbourne, VIC, 3800, Australia
| | - Travis C Porco
- University of California, San Francisco, San Francisco, CA, 94143, USA
| | | | - Lisa Reimer
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Kat S Rock
- University of Warwick, Coventry, CV4 7AL, UK
| | | | - Wilma Stolk
- Erasmus University Medical Center, 3015 CE, Rotterdam, Netherlands
| | | | - Steve J Torr
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
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Tanowitz HB, Machado FS, Spray DC, Friedman JM, Weiss OS, Lora JN, Nagajyothi J, Moraes DN, Garg NJ, Nunes MCP, Ribeiro ALP. Developments in the management of Chagas cardiomyopathy. Expert Rev Cardiovasc Ther 2015; 13:1393-409. [PMID: 26496376 DOI: 10.1586/14779072.2015.1103648] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Over 100 years have elapsed since the discovery of Chagas disease and there is still much to learn regarding pathogenesis and treatment. Although there are antiparasitic drugs available, such as benznidazole and nifurtimox, they are not totally reliable and often toxic. A recently released negative clinical trial with benznidazole in patients with chronic Chagas cardiomyopathy further reinforces the concerns regarding its effectiveness. New drugs and new delivery systems, including those based on nanotechnology, are being sought. Although vaccine development is still in its infancy, the reality of a therapeutic vaccine remains a challenge. New ECG methods may help to recognize patients prone to developing malignant ventricular arrhythmias. The management of heart failure, stroke and arrhythmias also remains a challenge. Although animal experiments have suggested that stem cell based therapy may be therapeutic in the management of heart failure in Chagas cardiomyopathy, clinical trials have not been promising.
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Affiliation(s)
- Herbert B Tanowitz
- a Department of Pathology , Albert Einstein College of Medicine , Bronx , NY , USA.,b Department of Medicine , Albert Einstein College of Medicine , Bronx , NY , USA
| | - Fabiana S Machado
- c Department of Biochemistry and Immunology, Institute of Biological Science , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.,d Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medical School , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - David C Spray
- b Department of Medicine , Albert Einstein College of Medicine , Bronx , NY , USA.,e Dominick P. Purpura Department of Neuroscience , Albert Einstein College of Medicine , Bronx , NY , USA
| | - Joel M Friedman
- f Department of Physiology & Biophysics , Albert Einstein College of Medicine , Bronx , NY , USA
| | - Oren S Weiss
- a Department of Pathology , Albert Einstein College of Medicine , Bronx , NY , USA
| | - Jose N Lora
- a Department of Pathology , Albert Einstein College of Medicine , Bronx , NY , USA
| | - Jyothi Nagajyothi
- g Public Health Research Institute, New Jersey Medical School , Rutgers University , Newark , NJ , USA
| | - Diego N Moraes
- d Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medical School , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.,h Department of Internal Medicine and University Hospital , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Nisha Jain Garg
- i Department of Microbiology & Immunology and Institute for Human Infections and Immunity , University of Texas Medical Branch , Galveston , TX , USA
| | - Maria Carmo P Nunes
- d Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medical School , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.,h Department of Internal Medicine and University Hospital , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Antonio Luiz P Ribeiro
- d Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medical School , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.,h Department of Internal Medicine and University Hospital , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
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Peterson JK, Bartsch SM, Lee BY, Dobson AP. Broad patterns in domestic vector-borne Trypanosoma cruzi transmission dynamics: synanthropic animals and vector control. Parasit Vectors 2015; 8:537. [PMID: 26489493 PMCID: PMC4618875 DOI: 10.1186/s13071-015-1146-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/05/2015] [Indexed: 12/22/2022] Open
Abstract
Background Chagas disease (caused by Trypanosoma cruzi) is the most important neglected tropical disease (NTD) in Latin America, infecting an estimated 5.7 million people in the 21 countries where it is endemic. It is one of the NTDs targeted for control and elimination by the 2020 London Declaration goals, with the first goal being to interrupt intra-domiciliary vector-borne T. cruzi transmission. A key question in domestic T. cruzi transmission is the role that synanthropic animals play in T. cruzi transmission to humans. Here, we ask, (1) do synanthropic animals need to be targeted in Chagas disease prevention policies?, and (2) how does the presence of animals affect the efficacy of vector control? Methods We developed a simple mathematical model to simulate domestic vector-borne T.cruzi transmission and to specifically examine the interaction between the presence of synanthropic animals and effects of vector control. We used the model to explore how the interactions between triatomine bugs, humans and animals impact the number and proportion of T. cruzi-infected bugs and humans. We then examined how T. cruzi dynamics change when control measures targeting vector abundance are introduced into the system. Results We found that the presence of synanthropic animals slows the speed of T. cruzi transmission to humans, and increases the sensitivity of T. cruzi transmission dynamics to vector control measures at comparable triatomine carrying capacities. However, T. cruzi transmission is amplified when triatomine carrying capacity increases with the abundance of syntathoropic hosts. Conclusions Our results suggest that in domestic T. cruzi transmission scenarios where no vector control measures are in place, a reduction in synanthropic animals may slow T. cruzi transmission to humans, but it would not completely eliminate transmission. To reach the 2020 goal of interrupting intra-domiciliary T. cruzi transmission, it is critical to target vector populations. Additionally, where vector control measures are in place, synanthropic animals may be beneficial.
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Affiliation(s)
- Jennifer K Peterson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
| | - Sarah M Bartsch
- Public Health Computational and Operations Research (PHICOR), John Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Bruce Y Lee
- Public Health Computational and Operations Research (PHICOR), John Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Andrew P Dobson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
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Martinez-Campos V, Martinez-Vega P, Ramirez-Sierra MJ, Rosado-Vallado M, Seid CA, Hudspeth EM, Wei J, Liu Z, Kwityn C, Hammond M, Ortega-López J, Zhan B, Hotez PJ, Bottazzi ME, Dumonteil E. Expression, purification, immunogenicity, and protective efficacy of a recombinant Tc24 antigen as a vaccine against Trypanosoma cruzi infection in mice. Vaccine 2015; 33:4505-12. [PMID: 26192358 DOI: 10.1016/j.vaccine.2015.07.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/12/2015] [Accepted: 07/07/2015] [Indexed: 12/22/2022]
Abstract
The Tc24 calcium binding protein from the flagellar pocket of Trypanosoma cruzi is under evaluation as a candidate vaccine antigen against Chagas disease. Previously, a DNA vaccine encoding Tc24 was shown to be an effective vaccine (both as a preventive and therapeutic intervention) in mice and dogs, as evidenced by reductions in T. cruzi parasitemia and cardiac amastigotes, as well as reduced cardiac inflammation and increased host survival. Here we developed a suitable platform for the large scale production of recombinant Tc24 (rTc24) and show that when rTc24 is combined with a monophosphoryl-lipid A (MPLA) adjuvant, the formulated vaccine induces a Th1-biased immune response in mice, comprised of elevated IgG2a antibody levels and interferon-gamma levels from splenocytes, compared to controls. These immune responses also resulted in statistically significant decreased T. cruzi parasitemia and cardiac amastigotes, as well as increased survival following T. cruzi challenge infections, compared to controls. Partial protective efficacy was shown regardless of whether the antigen was expressed in Escherichia coli or in yeast (Pichia pastoris). While mouse vaccinations will require further modifications in order to optimize protective efficacy, such studies provide a basis for further evaluations of vaccines comprised of rTc24, together with alternative adjuvants and additional recombinant antigens.
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Affiliation(s)
- Viridiana Martinez-Campos
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, 97000 Mérida, Yucatán, Mexico
| | - Pedro Martinez-Vega
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, 97000 Mérida, Yucatán, Mexico
| | - Maria Jesus Ramirez-Sierra
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, 97000 Mérida, Yucatán, Mexico
| | - Miguel Rosado-Vallado
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, 97000 Mérida, Yucatán, Mexico
| | - Christopher A Seid
- Sabin Vaccine Institute and 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 77030, USA
| | - Elissa M Hudspeth
- Sabin Vaccine Institute and 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 77030, USA
| | - Junfei Wei
- Sabin Vaccine Institute and 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 77030, USA
| | - Zhuyun Liu
- Sabin Vaccine Institute and 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 77030, USA
| | - Cliff Kwityn
- Sabin Vaccine Institute and 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 77030, USA
| | - Molly Hammond
- Sabin Vaccine Institute and 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 77030, USA
| | - Jaime Ortega-López
- Departamento de Biotecnología y Bioingeniería, CINVESTAV-IPN, Av. IPN 2508 Col., San Pedro Zacatenco 07360, Mexico D.F., Mexico
| | - Bin Zhan
- Sabin Vaccine Institute and 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 77030, USA
| | - Peter J Hotez
- Sabin Vaccine Institute and 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 77030, USA; Department of Biology, Baylor University, Waco, TX 76798, USA
| | - Maria Elena Bottazzi
- Sabin Vaccine Institute and 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 77030, USA; Department of Biology, Baylor University, Waco, TX 76798, USA
| | - Eric Dumonteil
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, 97000 Mérida, Yucatán, Mexico.
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Gupta S, Smith C, Auclair S, Delgadillo ADJ, Garg NJ. Therapeutic Efficacy of a Subunit Vaccine in Controlling Chronic Trypanosoma cruzi Infection and Chagas Disease Is Enhanced by Glutathione Peroxidase Over-Expression. PLoS One 2015; 10:e0130562. [PMID: 26075398 PMCID: PMC4468200 DOI: 10.1371/journal.pone.0130562] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 05/22/2015] [Indexed: 12/15/2022] Open
Abstract
Trypanosoma cruzi-induced oxidative and inflammatory responses are implicated in chagasic cardiomyopathy. In this study, we examined the therapeutic utility of a subunit vaccine against T. cruzi and determined if glutathione peroxidase (GPx1, antioxidant) protects the heart from chagasic pathogenesis. C57BL/6 mice (wild-type (WT) and GPx1 transgenic (GPxtg) were infected with T. cruzi and at 45 days post-infection (dpi), immunized with TcG2/TcG4 vaccine delivered by a DNA-prime/Protein-boost (D/P) approach. The plasma and tissue-sections were analyzed on 150 dpi for parasite burden, inflammatory and oxidative stress markers, inflammatory infiltrate and fibrosis. WT mice infected with T. cruzi had significantly more blood and tissue parasite burden compared with infected/GPxtg mice (n = 5-8, p<0.01). Therapeutic vaccination provided >15-fold reduction in blood and tissue parasites in both WT and GPxtg mice. The increase in plasma levels of myeloperoxidase (MPO, 24.7%) and nitrite (iNOS activity, 45%) was associated with myocardial increase in oxidant levels (3-4-fold) and non-responsive antioxidant status in chagasic/WT mice; and these responses were not controlled after vaccination (n = 5-7). The GPxtg mice were better equipped than the WT mice in controlling T. cruzi-induced inflammatory and oxidative stress markers. Extensive myocardial and skeletal tissue inflammation noted in chagasic/WT mice, was significantly more compared with chagasic/GPxtg mice (n = 4-6, p<0.05). Vaccination was equally effective in reducing the chronic inflammatory infiltrate in the heart and skeletal tissue of infected WT and GPxtg mice (n = 6, p<0.05). Hypertrophy (increased BNP and ANP mRNA) and fibrosis (increased collagen) of the heart were extensively present in chronically-infected WT and GPxtg mice and notably decreased after therapeutic vaccination. We conclude the therapeutic delivery of D/P vaccine was effective in arresting the chronic parasite persistence and chagasic pathology; and GPx1 over-expression provided additive benefits in reducing the parasite burden, inflammatory/oxidative stress and cardiac remodeling in Chagas disease.
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Affiliation(s)
- Shivali Gupta
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail: (SG); (NG)
| | - Charity Smith
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Sarah Auclair
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Anahi De Jesus Delgadillo
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Nisha Jain Garg
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute for Human Infections and Immunity and the Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Galveston, Texas, United States of America
- * E-mail: (SG); (NG)
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Gupta S, Garg NJ. A Two-Component DNA-Prime/Protein-Boost Vaccination Strategy for Eliciting Long-Term, Protective T Cell Immunity against Trypanosoma cruzi. PLoS Pathog 2015; 11:e1004828. [PMID: 25951312 PMCID: PMC4423834 DOI: 10.1371/journal.ppat.1004828] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 03/23/2015] [Indexed: 12/15/2022] Open
Abstract
In this study, we evaluated the long-term efficacy of a two-component subunit vaccine against Trypanosoma cruzi infection. C57BL/6 mice were immunized with TcG2/TcG4 vaccine delivered by a DNA-prime/Protein-boost (D/P) approach and challenged with T. cruzi at 120 or 180 days post-vaccination (dpv). We examined whether vaccine-primed T cell immunity was capable of rapid expansion and intercepting the infecting T. cruzi. Our data showed that D/P vaccine elicited CD4+ (30-38%) and CD8+ (22-42%) T cells maintained an effector phenotype up to 180 dpv, and were capable of responding to antigenic stimulus or challenge infection by a rapid expansion (CD8>CD4) with type 1 cytokine (IFNγ+ and TFNα+) production and cytolytic T lymphocyte (CTL) activity. Subsequently, challenge infection at 120 or 180 dpv, resulted in 2-3-fold lower parasite burden in vaccinated mice than was noted in unvaccinated/infected mice. Co-delivery of IL-12- and GMCSF-encoding expression plasmids provided no significant benefits in enhancing the anti-parasite efficacy of the vaccine-induced T cell immunity. Booster immunization (bi) with recombinant TcG2/TcG4 proteins 3-months after primary vaccine enhanced the protective efficacy, evidenced by an enhanced expansion (1.2-2.8-fold increase) of parasite-specific, type 1 CD4+ and CD8+ T cells and a potent CTL response capable of providing significantly improved (3-4.5-fold) control of infecting T. cruzi. Further, CD8+T cells in vaccinated/bi mice were predominantly of central memory phenotype, and capable of responding to challenge infection 4-6-months post bi by a rapid expansion to a poly-functional effector phenotype, and providing a 1.5-2.3-fold reduction in tissue parasite replication. We conclude that the TcG2/TcG4 D/P vaccine provided long-term anti-T. cruzi T cell immunity, and bi would be an effective strategy to maintain or enhance the vaccine-induced protective immunity against T. cruzi infection and Chagas disease. Chagas disease, caused by Trypanosoma cruzi infection, represents the third greatest tropical disease burden in the world. No vaccine or suitable treatment is available for control of this infection. Based upon several studies we have conducted, we believe that TcG2 and TcG4 candidate antigens that are highly conserved in T. cruzi, expressed in clinically relevant forms of the parasite, and recognized by both B and T cell responses in multiple hosts, are an excellent choice for subunit vaccine development. In this study, we demonstrate that the delivery of TcG2 and TcG4 as a DNA-prime/protein-boost vaccine provided long-term protection from challenge infection, and this protection was associated with elicitation of long-lived CD8+ effector T cells. The longevity and efficacy of vaccine could be enhanced by booster immunization. We believe that this is the first report demonstrating a) a subunit vaccine can be useful in achieving long-term protection against T. cruzi infection and Chagas disease, and b) the effector T cells can be long-lived and play a role in vaccine elicited protection from parasitic infection.
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Affiliation(s)
- Shivali Gupta
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch (UTMB), Galveston, Texas, United States of America
- * E-mail: (SG); (NJG)
| | - Nisha J. Garg
- Department of Microbiology and Immunology, School of Medicine, University of Texas Medical Branch (UTMB), Galveston, Texas, United States of America
- Department of Pathology, School of Medicine, University of Texas Medical Branch (UTMB), Galveston, Texas, United States of America
- Institute for Human Infections and Immunity and the Sealy Center for Vaccine Development, University of Texas Medical Branch (UTMB), Galveston, Texas, United States of America
- * E-mail: (SG); (NJG)
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Lee BY, Bartsch SM, Gorham KM. Economic and financial evaluation of neglected tropical diseases. ADVANCES IN PARASITOLOGY 2015; 87:329-417. [PMID: 25765199 DOI: 10.1016/bs.apar.2015.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Economic and financing studies are particularly important for decision-making when resources are scarce or considerably limited. This is the case for neglected tropical diseases (NTDs). In fact, the definition of NTDs is an economic one. The shortage of resources for NTD control may be due in large part to the fact that the burden of NTDs and economic value of control measures have not been fully characterized. A number of economic study methodologies are available: cost of illness can quantify the extent, magnitude, and change of a problem; cost of intervention studies can outline the feasibility and guide the design of a policy or intervention; and cost-benefit, cost-effectiveness, and return-on-investment studies can determine the potential value of different interventions and policies. NTDs have unique characteristics that require special consideration in such analyses. Hence, approaches used for other diseases may need modifications to capture the full impact of NTDs. While the existing literature has made important findings, there is a need for substantially more work, as many NTDs and their associated interventions and policies require more evaluation. With increasing work in this area, NTDs may not be as 'neglected' in the future as they are now.
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Affiliation(s)
- Bruce Y Lee
- Public Health Computational and Operations Research (PHICOR) and International Vaccine Access Center (IVAC), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sarah M Bartsch
- Public Health Computational and Operations Research (PHICOR) and International Vaccine Access Center (IVAC), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Katrin M Gorham
- Public Health Computational and Operations Research (PHICOR) and International Vaccine Access Center (IVAC), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Nouvellet P, Cucunubá ZM, Gourbière S. Ecology, evolution and control of Chagas disease: a century of neglected modelling and a promising future. ADVANCES IN PARASITOLOGY 2015; 87:135-91. [PMID: 25765195 DOI: 10.1016/bs.apar.2014.12.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
More than 100 years after its formal description, Chagas disease remains a major public health concern in Latin America with a yearly burden of 430,000 Disability-Adjusted Life Years (DALYs). The aetiological agent, a protozoan named Trypanosoma cruzi, is mainly transmitted to mammalian hosts by triatomine vectors. Multiple species of mammals and triatomines can harbour and transmit the parasite, and the feeding range of triatomine species typically includes many noncompetent hosts. Furthermore, the transmission of the pathogen can occur via several routes including the typical vector's faeces, but also oral, congenital and blood transfusion routes. These ecological and epidemiological complexities of the disease have hindered many control initiatives. In such a context, mathematical models provide invaluable tools to explore and understand the dynamics of T. cruzi transmission, and to design, optimize and monitor the efficacy of control interventions. We intend here to provide the first review of the mathematical models of Chagas disease, focussing on how they have contributed to our understanding of (1) the population dynamics and control of triatomine vectors, and (2) the epidemiology of T. cruzi infections. We also aim at suggesting promising lines of modelling that could further improve our understanding of the ecology, evolution, and control of the disease.
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Affiliation(s)
- Pierre Nouvellet
- Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Zulma M Cucunubá
- Grupo de Parasitología, Instituto Nacional de Salud, Colombia; Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Sébastien Gourbière
- Institut de Modélisation et d'Analyse en Géo-Environnements et Santé (IMAGES), Université de Perpignan Via Domitia, Perpignan, France
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Sánchez-Valdéz FJ, Pérez Brandán C, Ferreira A, Basombrío MÁ. Gene-deleted live-attenuated Trypanosoma cruzi parasites as vaccines to protect against Chagas disease. Expert Rev Vaccines 2014; 14:681-97. [PMID: 25496192 DOI: 10.1586/14760584.2015.989989] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. This illness is now becoming global, mainly due to congenital transmission, and so far, there are no prophylactic or therapeutic vaccines available to either prevent or treat Chagas disease. Therefore, different approaches aimed at identifying new protective immunogens are urgently needed. Live vaccines are likely to be more efficient in inducing protection, but safety issues linked with their use have been raised. The development of improved protozoan genetic manipulation tools and genomic and biological information has helped to increase the safety of live vaccines. These advances have generated a renewed interest in the use of genetically attenuated parasites as vaccines against Chagas disease. This review discusses the protective capacity of genetically attenuated parasite vaccines and the challenges and perspectives for the development of an effective whole-parasite Chagas disease vaccine.
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Machuca MA, Suárez EU, Echeverría LE, Martín J, González CI. SNP/haplotype associations of CCR2 and CCR5 genes with severity of chagasic cardiomyopathy. Hum Immunol 2014; 75:1210-5. [DOI: 10.1016/j.humimm.2014.09.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 09/27/2014] [Accepted: 09/27/2014] [Indexed: 10/24/2022]
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Turner HC, Walker M, French MD, Blake IM, Churcher TS, Basáñez MG. Neglected tools for neglected diseases: mathematical models in economic evaluations. Trends Parasitol 2014; 30:562-70. [PMID: 25455565 DOI: 10.1016/j.pt.2014.10.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/01/2014] [Accepted: 10/07/2014] [Indexed: 12/27/2022]
Abstract
Despite many current interventions against neglected tropical diseases (NTDs) being highly cost-effective, new strategies are needed to reach the WHO's control and elimination goals. Here we argue for the importance of incorporating economic evaluations of new strategies in decisions regarding resource allocation. Such evaluation should ideally be conducted using dynamic transmission models that capture inherent nonlinearities in transmission and the indirect benefits ('herd effects') of interventions. A systematic review of mathematical models that have been used for economic analysis of interventions against the ten NTDs covered by the London Declaration reveals that only 16 out of 49 studies used dynamic transmission models, highlighting a fundamental--but addressable--gap in the evaluation of interventions against NTDs.
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Affiliation(s)
- Hugo C Turner
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK; Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK.
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK; Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK
| | - Michael D French
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK; Schistosomiasis Control Initiative, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK
| | - Isobel M Blake
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK; MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, London W2 1PG, UK
| | - Thomas S Churcher
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK
| | - María-Gloria Basáñez
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK; Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's Campus), Imperial College London, Norfolk Place, London W2 1PG, UK
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Rodrigues MM, Ersching J. Neglected tropical diseases, bioinformatics, and vaccines. J Infect Dis 2014; 211:175-7. [PMID: 25070940 DOI: 10.1093/infdis/jiu420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mauricio Martins Rodrigues
- Centro de Terapia Celular e Molecular Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, Brazil
| | - Jonatan Ersching
- Centro de Terapia Celular e Molecular Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, Brazil
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Teh-Poot C, Tzec-Arjona E, Martínez-Vega P, Ramirez-Sierra MJ, Rosado-Vallado M, Dumonteil E. From genome screening to creation of vaccine against Trypanosoma cruzi by use of immunoinformatics. J Infect Dis 2014; 211:258-66. [PMID: 25070943 DOI: 10.1093/infdis/jiu418] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, and activation of CD8(+) T cells is crucial for a protective immune response. Therefore, the identification of antigens with major histocompatibility complex class I epitopes is a crucial step for vaccine development against T. cruzi. Our aim was to identify novel antigens and epitopes by immunoinformatics analysis of the parasite proteome (12 969 proteins) and to validate their immunotherapeutic potential in infected mice. We identified 172 predicted epitopes, using NetMHC and RANKPEP. The corresponding protein sequences were reanalyzed to generate a consensus prediction, and 26 epitopes were selected for in vivo validation. The interferon γ (IFN-γ) recall response of splenocytes from T. cruzi-infected mice confirmed that 10 of 26 epitopes (38%) induced IFN-γ production. The immunotherapeutic potential of a mixture of all 10 peptides was evaluated in infected mice. The therapeutic vaccine was able to control T. cruzi infection, as evidenced by reduced parasitemia, cardiac tissue inflammation, and parasite burden and increased survival. These findings illustrate the benefits of this approach for the rapid development of a vaccine against pathogens with large genomes. The identified peptides and the proteins from which they are derived are excellent candidates for the development of a vaccine against T. cruzi.
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Affiliation(s)
- Christian Teh-Poot
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Evelyn Tzec-Arjona
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Pedro Martínez-Vega
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Maria Jesus Ramirez-Sierra
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Miguel Rosado-Vallado
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Eric Dumonteil
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr Hideyo Noguchi, Universidad Autónoma de Yucatán, Mérida, Mexico Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
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CD8(+) T cell-mediated immunity during Trypanosoma cruzi infection: a path for vaccine development? Mediators Inflamm 2014; 2014:243786. [PMID: 25104879 PMCID: PMC4102079 DOI: 10.1155/2014/243786] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 06/15/2014] [Indexed: 11/05/2022] Open
Abstract
MHC-restricted CD8+ T cells are important during infection with the intracellular protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Experimental studies performed in the past 25 years have elucidated a number of features related to the immune response mediated by these T cells, which are important for establishing the parasite/host equilibrium leading to chronic infection. CD8+ T cells are specific for highly immunodominant antigens expressed by members of the trans-sialidase family. After infection, their activation is delayed, and the cells display a high proliferative activity associated with high apoptotic rates. Although they participate in parasite control and elimination, they are unable to clear the infection due to their low fitness, allowing the parasite to establish the chronic phase when these cells then play an active role in the induction of heart immunopathology. Vaccination with a number of subunit recombinant vaccines aimed at eliciting specific CD8+ T cells can reverse this path, thereby generating a productive immune response that will lead to the control of infection, reduction of symptoms, and reduction of disease transmission. Due to these attributes, activation of CD8+ T lymphocytes may constitute a path for the development of a veterinarian or human vaccine.
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Genetic vaccination against experimental infection with myotropic parasite strains of Trypanosoma cruzi. Mediators Inflamm 2014; 2014:605023. [PMID: 25061263 PMCID: PMC4098640 DOI: 10.1155/2014/605023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 05/25/2014] [Indexed: 01/29/2023] Open
Abstract
In earlier studies, we reported that a heterologous prime-boost regimen using recombinant plasmid DNA followed by replication-defective adenovirus vector, both containing Trypanosoma cruzi genes encoding trans-sialidase (TS) and amastigote surface protein (ASP) 2, provided protective immunity against experimental infection with a reticulotropic strain of this human protozoan parasite. Herein, we tested the outcome of genetic vaccination of F1 (CB10XBALB/c) mice challenged with myotropic parasite strains (Brazil and Colombian). Initially, we determined that the coadministration during priming of a DNA plasmid containing the murine IL-12 gene improved the immune response and was essential for protective immunity elicited by the heterologous prime-boost regimen in susceptible male mice against acute lethal infections with these parasites. The prophylactic or therapeutic vaccination of resistant female mice led to a drastic reduction in the number of inflammatory infiltrates in cardiac and skeletal muscles during the chronic phase of infection with either strain. Analysis of the electrocardiographic parameters showed that prophylactic vaccination reduced the frequencies of sinus arrhythmia and atrioventricular block. Our results confirmed that prophylactic vaccination using the TS and ASP-2 genes benefits the host against acute and chronic pathologies caused by T. cruzi and should be further evaluated for the development of a veterinary or human vaccine against Chagas disease.
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Ramsey JM, Elizondo-Cano M, Sanchez-González G, Peña-Nieves A, Figueroa-Lara A. Opportunity cost for early treatment of Chagas disease in Mexico. PLoS Negl Trop Dis 2014; 8:e2776. [PMID: 24743112 PMCID: PMC3990484 DOI: 10.1371/journal.pntd.0002776] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 02/22/2014] [Indexed: 11/18/2022] Open
Abstract
Background Given current neglect for Chagas disease in public health programs in Mexico, future healthcare and economic development policies will need a more robust model to analyze costs and impacts of timely clinical attention of infected populations. Methodology/Principal Findings A Markov decision model was constructed to simulate the natural history of a Chagas disease cohort in Mexico and to project the associated short and long-term clinical outcomes and corresponding costs. The lifetime cost for a timely diagnosed and treated Chagas disease patient is US$ 10,160, while the cost for an undiagnosed individual is US$ 11,877. The cost of a diagnosed and treated case increases 24-fold from early acute to indeterminate stage. The major cost component for lifetime cost was working days lost, between 44% and 75%, depending on the program scenario for timely diagnosis and treatment. Conclusions/Significance In the long term, it is cheaper to diagnose and treat chagasic patients early, instead of doing nothing. This finding by itself argues for the need to shift current policy, in order to prioritize and attend this neglected disease for the benefit of social and economic development, which implies including treatment drugs in the national formularies. Present results are even more relevant, if one considers that timely diagnosis and treatment can arrest clinical progression and enhance a chronic patient's quality of life. Chagas disease is caused by the flagellated protozoan parasite Trypanosoma cruzi, vectored in Mexico in both rural and urban areas via one of 18 triatomine bug species. Despite ample morbidity and mortality evidence, however, health policy managers in Mexico have continued to neglect prevention, control and clinical attention for the disease. A computer simulation Markov model was programmed and fed with information from published evidence and an expert panel. The lifetime cost for a timely diagnosed and treated Chagas disease patient is US$ 10,160, while the cost for an undiagnosed individual is US$ 11,877. The cost of a diagnosed and treated case increases 24-fold from early acute to indeterminate stage. The major cost component for lifetime cost was working days lost, between 44% and 75%, depending on the program scenario for timely diagnosis and treatment. Timely medical attention for infected individuals is cheaper than doing nothing, especially if life and labor costs are included. The evidence provided, essential for decision-making, should be used to develop disease-specific prevention, control and patient clinical diagnosis and treatment policies for Chagas disease in Mexico.
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Affiliation(s)
- Janine M. Ramsey
- Regional Center for Public Health Research, National Institute for Public Health Research, Tapachula, Chiapas, Mexico
| | - Miguel Elizondo-Cano
- Center for Research in Health Systems, National Institute for Public Health Research, Cuernavaca, Mexico
| | - Gilberto Sanchez-González
- Center for Research in Health Systems, National Institute for Public Health Research, Cuernavaca, Mexico
| | | | - Alejandro Figueroa-Lara
- Epidemiological Research Unit and Health Services, National Medical Center XXI Century, Mexican Social Security Institute, Mexico City, Mexico
- * E-mail:
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Basso B, Moretti E, Fretes R. Vaccination with Trypanosoma rangeli induces resistance of guinea pigs to virulent Trypanosoma cruzi. Vet Immunol Immunopathol 2014; 157:119-23. [DOI: 10.1016/j.vetimm.2013.10.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 10/01/2013] [Accepted: 10/21/2013] [Indexed: 11/27/2022]
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Quijano-Hernández IA, Castro-Barcena A, Vázquez-Chagoyán JC, Bolio-González ME, Ortega-López J, Dumonteil E. Preventive and therapeutic DNA vaccination partially protect dogs against an infectious challenge with Trypanosoma cruzi. Vaccine 2013; 31:2246-52. [DOI: 10.1016/j.vaccine.2013.03.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 02/06/2013] [Accepted: 03/04/2013] [Indexed: 10/27/2022]
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Lee BY, Bacon KM, Bottazzi ME, Hotez PJ. Global economic burden of Chagas disease: a computational simulation model. THE LANCET. INFECTIOUS DISEASES 2013; 13:342-8. [PMID: 23395248 PMCID: PMC3763184 DOI: 10.1016/s1473-3099(13)70002-1] [Citation(s) in RCA: 414] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND As Chagas disease continues to expand beyond tropical and subtropical zones, a growing need exists to better understand its resulting economic burden to help guide stakeholders such as policy makers, funders, and product developers. We developed a Markov simulation model to estimate the global and regional health and economic burden of Chagas disease from the societal perspective. METHODS Our Markov model structure had a 1 year cycle length and consisted of five states: acute disease, indeterminate disease, cardiomyopathy with or without congestive heart failure, megaviscera, and death. Major model parameter inputs, including the annual probabilities of transitioning from one state to another, and present case estimates for Chagas disease came from various sources, including WHO and other epidemiological and disease-surveillance-based reports. We calculated annual and lifetime health-care costs and disability-adjusted life-years (DALYs) for individuals, countries, and regions. We used a discount rate of 3% to adjust all costs and DALYs to present-day values. FINDINGS On average, an infected individual incurs US$474 in health-care costs and 0·51 DALYs annually. Over his or her lifetime, an infected individual accrues an average net present value of $3456 and 3·57 DALYs. Globally, the annual burden is $627·46 million in health-care costs and 806,170 DALYs. The global net present value of currently infected individuals is $24·73 billion in health-care costs and 29,385,250 DALYs. Conversion of this burden into costs results in annual per-person costs of $4660 and lifetime per-person costs of $27,684. Global costs are $7·19 billion per year and $188·80 billion per lifetime. More than 10% of these costs emanate from the USA and Canada, where Chagas disease has not been traditionally endemic. A substantial proportion of the burden emerges from lost productivity from cardiovascular disease-induced early mortality. INTERPRETATION The economic burden of Chagas disease is similar to or exceeds those of other prominent diseases globally (eg, rotavirus $2·0 billion, cervical cancer $4·7 billion) even in the USA (Lyme disease $2·5 billion), where Chagas disease has not been traditionally endemic, suggesting an economic argument for more attention and efforts towards control of Chagas disease. FUNDING Bill & Melinda Gates Foundation, the National Institute of General Medical Sciences Models of Infectious Disease Agent Study.
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Affiliation(s)
- Bruce Y Lee
- Public Health Computational and Operations Research, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
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Recombinant yellow fever viruses elicit CD8+ T cell responses and protective immunity against Trypanosoma cruzi. PLoS One 2013; 8:e59347. [PMID: 23527169 PMCID: PMC3601986 DOI: 10.1371/journal.pone.0059347] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 02/13/2013] [Indexed: 12/19/2022] Open
Abstract
Chagas’ disease is a major public health problem affecting nearly 10 million in Latin America. Despite several experimental vaccines have shown to be immunogenic and protective in mouse models, there is not a current vaccine being licensed for humans or in clinical trial against T. cruzi infection. Towards this goal, we used the backbone of Yellow Fever (YF) 17D virus, one of the most effective and well-established human vaccines, to express an immunogenic fragment derived from T. cruzi Amastigote Surface Protein 2 (ASP-2). The cDNA sequence of an ASP-2 fragment was inserted between E and NS1 genes of YF 17D virus through the construction of a recombinant heterologous cassette. The replication ability and genetic stability of recombinant YF virus (YF17D/ENS1/Tc) was confirmed for at least six passages in Vero cells. Immunogenicity studies showed that YF17D/ENS1/Tc virus elicited neutralizing antibodies and gamma interferon (IFN-γ) producing-cells against the YF virus. Also, it was able to prime a CD8+ T cell directed against the transgenic T. cruzi epitope (TEWETGQI) which expanded significantly as measured by T cell-specific production of IFN-γ before and after T. cruzi challenge. However, most important for the purposes of vaccine development was the fact that a more efficient protective response could be seen in mice challenged after vaccination with the YF viral formulation consisting of YF17D/ENS1/Tc and a YF17D recombinant virus expressing the TEWETGQI epitope at the NS2B-3 junction. The superior protective immunity observed might be due to an earlier priming of epitope-specific IFN-γ-producing T CD8+ cells induced by vaccination with this viral formulation. Our results suggest that the use of viral formulations consisting of a mixture of recombinant YF 17D viruses may be a promising strategy to elicit protective immune responses against pathogens, in general.
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Pires DEV, de Melo-Minardi RC, da Silveira CH, Campos FF, Meira W. aCSM: noise-free graph-based signatures to large-scale receptor-based ligand prediction. ACTA ACUST UNITED AC 2013; 29:855-61. [PMID: 23396119 DOI: 10.1093/bioinformatics/btt058] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
MOTIVATION Receptor-ligand interactions are a central phenomenon in most biological systems. They are characterized by molecular recognition, a complex process mainly driven by physicochemical and structural properties of both receptor and ligand. Understanding and predicting these interactions are major steps towards protein ligand prediction, target identification, lead discovery and drug design. RESULTS We propose a novel graph-based-binding pocket signature called aCSM, which proved to be efficient and effective in handling large-scale protein ligand prediction tasks. We compare our results with those described in the literature and demonstrate that our algorithm overcomes the competitor's techniques. Finally, we predict novel ligands for proteins from Trypanosoma cruzi, the parasite responsible for Chagas disease, and validate them in silico via a docking protocol, showing the applicability of the method in suggesting ligands for pockets in a real-world scenario. AVAILABILITY AND IMPLEMENTATION Datasets and the source code are available at http://www.dcc.ufmg.br/∼dpires/acsm. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Douglas E V Pires
- Department of Computer Science, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha Belo Horizonte - MG, 31270-901, Brazil.
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Hotez PJ, Bethony JM. Parasitic disease vaccines. Vaccines (Basel) 2013. [DOI: 10.1016/b978-1-4557-0090-5.00059-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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Hotez PJ, Dumonteil E, Heffernan MJ, Bottazzi ME. Innovation for the 'bottom 100 million': eliminating neglected tropical diseases in the Americas. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 764:1-12. [PMID: 23654053 DOI: 10.1007/978-1-4614-4726-9_1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
An estimated 100 million people in the Latin American and Caribbean (LAC) region live on less than US$2 per day, while another 46 million people in the US live below that nation's poverty line. Almost all of the 'bottom 100 million' people suffer from at least one neglected tropical disease (NTD), including one-half of the poorest people in the region infected with hookworms, 10% with Chagas disease, and up to 1-2% with dengue, schistosomiasis, and/or leishmaniasis. In the US, NTDs such as Chagas disease, cysticercosis, toxocariasis, and trichomoniasis are also common among poor populations. These NTDs trap the poorest people in the region in poverty, because of their impact on maternal and child health, and occupational productivity. Through mass drug administration (MDA), several NTDs are on the verge of elimination in the Americas, including lymphatic filariasis, onchocerciasis, trachoma, and possibly leprosy. In addition, schistosomiasis may soon be eliminated in the Caribbean. However, for other NTDs including hookworm infection, Chagas disease, dengue, schistosomiasis, and leishmaniasis, a new generation of 'anti-poverty vaccines' will be required. Several vaccines for dengue are under development by multinational pharmaceutical companies, whereas others are being pursued through non-profit product development partnerships (PDPs), in collaboration with developing country manufacturers in Brazil and Mexico. The Sabin Vaccine Institute PDP is developing a primarily preventive bivalent recombinant human hookworm vaccine, which is about to enter phase 1 clinical testing in Brazil, as well as a new therapeutic Chagas disease vaccine in collaboration with several Mexican institutions. The Chagas disease vaccine would be administered to seropositive patients to delay or prevent the onset of Chagasic cardiomyopathy (secondary prevention). Together, MDA and the development of new anti-poverty vaccines afford an opportunity to implement effective control and elimination strategies for the major NTDs in the Americas.
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Affiliation(s)
- Peter J Hotez
- Sabin Vaccine Institute, Texas Children's Center for Vaccine Development, Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Tropical Medicine, Baylor College of Medicine, Houston, USA.
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Dumonteil E, Bottazzi ME, Zhan B, Heffernan MJ, Jones K, Valenzuela JG, Kamhawi S, Ortega J, de Leon Rosales SP, Lee BY, Bacon KM, Fleischer B, Slingsby BT, Cravioto MB, Tapia-Conyer R, Hotez PJ. Accelerating the development of a therapeutic vaccine for human Chagas disease: rationale and prospects. Expert Rev Vaccines 2012; 11:1043-55. [PMID: 23151163 PMCID: PMC3819810 DOI: 10.1586/erv.12.85] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chagas disease is a leading cause of heart disease affecting approximately 10 million people in Latin America and elsewhere worldwide. The two major drugs available for the treatment of Chagas disease have limited efficacy in Trypanosoma cruzi-infected adults with indeterminate (patients who have seroconverted but do not yet show signs or symptoms) and determinate (patients who have both seroconverted and have clinical disease) status; they require prolonged treatment courses and are poorly tolerated and expensive. As an alternative to chemotherapy, an injectable therapeutic Chagas disease vaccine is under development to prevent or delay Chagasic cardiomyopathy in patients with indeterminate or determinate status. The bivalent vaccine will be comprised of two recombinant T. cruzi antigens, Tc24 and TSA-1, formulated on alum together with the Toll-like receptor 4 agonist, E6020. Proof-of-concept for the efficacy of these antigens was obtained in preclinical testing at the Autonomous University of Yucatan. Here the authors discuss the potential for a therapeutic Chagas vaccine as well as the progress made towards such a vaccine, and the authors articulate a roadmap for the development of the vaccine as planned by the nonprofit Sabin Vaccine Institute Product Development Partnership and Texas Children's Hospital Center for Vaccine Development in collaboration with an international consortium of academic and industrial partners in Mexico, Germany, Japan, and the USA.
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Affiliation(s)
- Eric Dumonteil
- Laboratorio de Parasitología Centro De Investigaciones Regional, “Dr. Hideo Noguchi” Autonomous University of Yucatan (UADY), Merida, Mexico
| | - Maria Elena Bottazzi
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics (Section of Pediatric Tropical Medicine) and Molecular Virology & Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Bin Zhan
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Department of Pediatrics (Section of Pediatric Tropical Medicine), National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Michael J Heffernan
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Department of Pediatrics (Section of Pediatric Tropical Medicine), National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Kathryn Jones
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics (Section of Pediatric Tropical Medicine) and Molecular Virology & Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Jesus G Valenzuela
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Shaden Kamhawi
- Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Jaime Ortega
- Departamento de Biotecnología y Bioingeniería, Centro de Investigacion y de Estudios Avanzados - Instituto Politécnico Nacional (CINVESTAV-IPN), Mexico City, Mexico
| | | | - Bruce Y Lee
- Public Health Computational and Operations Research (PHICOR), University of Pittsburgh, Pittsburgh PA, USA
| | - Kristina M Bacon
- Public Health Computational and Operations Research (PHICOR), University of Pittsburgh, Pittsburgh PA, USA
| | | | | | | | | | - Peter J Hotez
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Departments of Pediatrics (Section of Pediatric Tropical Medicine) and Molecular Virology & Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
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