501
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Flow Cytometry-Based Assessment of Antibody Function Against Malaria Pre-erythrocytic Infection. Methods Mol Biol 2015; 1325:49-58. [PMID: 26450378 DOI: 10.1007/978-1-4939-2815-6_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The development of new interventional strategies against pre-erythrocytic malaria is hampered by the lack of standardized approaches to assess inhibition of sporozoite infection of hepatocytes. The following methodology, based on flow cytometry, can be used to quantitatively assess P. falciparum sporozoite infection in vitro in medium throughput. In addition to assessing the efficacy of antibodies, this assay has a wide variety of applications for investigating basic science questions about the malaria liver stage. This approach is easily applied in a variety of laboratory settings, assesses the functionality of antibody responses against malaria sporozoites, and can be adapted for the limited quantities of sample which are typically available from clinical investigations.
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502
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Guthmiller JJ, Zander RA, Butler NS. Measurement of the T Cell Response to Preerythrocytic Vaccination in Mice. Methods Mol Biol 2015; 1325:19-37. [PMID: 26450376 DOI: 10.1007/978-1-4939-2815-6_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Whole attenuated parasite vaccines designed to elicit immunity against the clinically silent preerythrocytic stage of Plasmodium infection represent the most efficacious experimental platforms currently in clinical trial. Studies in rodents and humans show that T cells mediate vaccine-induced protection. Thus, determining the quantitative and qualitative properties of these T cells remains a major research focus. Most rodent models of preerythrocytic anti-Plasmodium vaccination focus on circumsporozoite-specific CD8 T cell responses in BALB/c mice. However, CD4 T cells and non-circumsporozoite-specific CD8 T cells also significantly contribute to protection. Here we describe alternative approaches that enable detection and functional characterization of total CD8 and CD4 T cell responses induced by preerythrocytic vaccination in mice. These flow cytometry-based approaches rely on monitoring the modulation of expressed integrins and co-receptors on the surface of T cells in vaccinated mice. The approaches enable direct determination of the magnitude, kinetics, distribution, phenotype, and functional features of T cell responses induced by infection or whole-parasite vaccination using any mouse-parasite species combination.
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Affiliation(s)
- Jenna J Guthmiller
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma, OK, 73104, USA
| | - Ryan A Zander
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma, OK, 73104, USA
| | - Noah S Butler
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Biomedical Sciences Building, Room 1035, 940 Stanton L. Young Blvd., Oklahoma, OK, 73104, USA.
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503
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Siegel FR. Progressive Adaptation: The Key to Sustaining a Growing Global Population. SPRINGERBRIEFS IN ENVIRONMENTAL SCIENCE 2015. [PMCID: PMC7153416 DOI: 10.1007/978-3-319-09686-5_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Adaptation is an evolving long-term process during which a population of life forms adjusts to changes in its habitat and surrounding environments. Adaptation by the global community as a unit is vital to cope with the effects of increasing populations, global warming/climate change, the chemical, biological, and physical impacts on life-sustaining ecosystems, and competition for life sustaining and economically important natural resources. The latter include water, food, energy, metal ores, industrial minerals, and wood. Within this framework, it is necessary to adapt as well to changes in local and regional physical conditions brought on by natural and anthropogenic hazards, by health threats of epidemic or pandemic reach, by social conditions such as conflicts driven by religious and ethnic fanaticism, and by tribalism and clan ties.
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504
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Sack BK, Miller JL, Vaughan AM, Kappe SHI. Measurement of Antibody-Mediated Reduction of Plasmodium yoelii Liver Burden by Bioluminescent Imaging. Methods Mol Biol 2015; 1325:69-80. [PMID: 26450380 PMCID: PMC8441651 DOI: 10.1007/978-1-4939-2815-6_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Antibodies against the infectious sporozoite stage of malaria have been shown to be effective in preventing infection of the liver and in mitigating the ensuing blood stage. However, only a handful of antibody targets have been vetted and shown to be successful in mediating in vivo protection. Even more limited are the means with which to measure how effectively antibodies can reduce the number of parasites establishing infection in the liver. Traditionally, only qPCR of infected mouse livers could accurately measure liver parasite burden. However, this procedure requires sacrifice of the animal and precludes monitoring of the ensuing blood stage infection. Herein we describe a method of accurately assessing antibody-mediated reduction of parasite liver burden by combining passive or active immunization of mice and mosquito bite challenge with luciferase-expressing transgenic P. yoelii parasites. This method is rapid, reliable and allows for observation of blood stage disease in the same animal. This model will prove integral in screening the efficacy of novel antibody targets as the search for a more effective malaria vaccine continues.
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Affiliation(s)
- Brandon K Sack
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA.
| | - Jessica L Miller
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
| | - Ashley M Vaughan
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
| | - Stefan H I Kappe
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
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505
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Nagano S, Lin TY, Edula JR, Heddle JG. Unique features of apicoplast DNA gyrases from Toxoplasma gondii and Plasmodium falciparum. BMC Bioinformatics 2014; 15:416. [PMID: 25523502 PMCID: PMC4297366 DOI: 10.1186/s12859-014-0416-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 12/10/2014] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND DNA gyrase, an enzyme once thought to be unique to bacteria, is also found in some eukaryotic plastids including the apicoplast of Apicomplexa such as Plasmodium falciparum and Toxoplasma gondii which are important disease-causing organisms. DNA gyrase is an excellent target for antibacterial drugs, yet such antibacterials seem ineffective against Apicomplexa. Characterisation of the apicoplast gyrases would be a useful step towards understanding why this should be so. While purification of active apicoplast gyrase has proved impossible to date, in silico analyses have allowed us to discover differences in the apicoplast proteins. The resulting predicted structural and functional differences will be a first step towards development of apicoplast-gyrase specific inhibitors. RESULTS We have carried out sequence analysis and structural predictions of the enzymes from the two species and find that P. falciparum gyrase lacks a GyrA box, but T. gondii may retain one. All proteins contained signal/transport peptides for localization to the apicoplast but T. gondii Gyrase B protein lacks the expected hydrophobic region. The most significant difference is in the GyrA C-terminal domain: While the cores of the proteins, including DNA binding and cleavage regions are essentially unchanged, both apicoplast gyrase A proteins have C-terminal domains that are significantly larger than bacterial counterparts and are predicted to have different structures. CONCLUSION The apicoplast gyrases differ significantly from bacterial gyrases while retaining similar core domains. T. gondii Gyrase B may have an unusual or inefficient mechanism of localisation to the apicoplast. P.falciparum gyrase, lacks a GyrA box and is therefore likely to be inefficient in DNA supercoiling. The C-terminal domains of both apicoplast Gyrase A proteins diverge significantly from the bacterial proteins. We predict that an additional structural element is present in the C-terminal domain of both apicoplast Gyrase A proteins, including the possibility of a β-pinwheel with a non-canonical number of blades. These differences undoubtedly will affect the DNA supercoiling mechanism and have perhaps evolved to compensate for the lack of Topoisomerase IV in the apicoplast. These data will be useful first step towards further characterisation and development of inhibitors for apicoplast gyrases.
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Affiliation(s)
- Soshichiro Nagano
- Heddle Initiative Research Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
| | - Ting-Yu Lin
- Heddle Initiative Research Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
| | - Jyotheeswara Reddy Edula
- Heddle Initiative Research Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan. .,Current address: Department of Molecular Protozoology, Research Institute for Microbial Diseases (RIMD), Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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506
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Jagannathan P, Nankya F, Stoyanov C, Eccles-James I, Sikyomu E, Naluwu K, Wamala S, Nalubega M, Briggs J, Bowen K, Bigira V, Kapisi J, Kamya MR, Dorsey G, Feeney ME. IFNγ Responses to Pre-erythrocytic and Blood-stage Malaria Antigens Exhibit Differential Associations With Past Exposure and Subsequent Protection. J Infect Dis 2014; 211:1987-96. [PMID: 25520427 DOI: 10.1093/infdis/jiu814] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 12/10/2014] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The malaria-specific T-cell response is believed to be important for protective immunity. Antimalarial chemoprevention may affect this response by altering exposure to malaria antigens. METHODS We performed interferon γ (IFNγ) ELISpot assays to assess the cellular immune response to blood-stage and pre-erythrocytic antigens longitudinally from 1 to 3 years of age in 196 children enrolled in a randomized trial of antimalarial chemoprevention in Tororo, Uganda, an area of high transmission intensity. RESULTS IFNγ responses to blood-stage antigens, particularly MSP1, were frequently detected, strongly associated with recent malaria exposure, and lower in those adherent to chemoprevention compared to nonadherent children and those randomized to no chemoprevention. IFNγ responses to pre-erythrocytic antigens were infrequent and similar between children randomized to chemoprevention or no chemoprevention. Responses to blood-stage antigens were not associated with subsequent protection from malaria (aHR 0.96, P = .83), but responses to pre-erythrocytic antigens were associated with protection after adjusting for prior malaria exposure (aHR 0.52, P = .009). CONCLUSIONS In this high transmission setting, IFNγ responses to blood-stage antigens were common and associated with recent exposure to malaria but not protection from subsequent malaria. Responses to pre-erythrocytic antigens were uncommon, not associated with exposure but were associated with protection from subsequent malaria.
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Affiliation(s)
- Prasanna Jagannathan
- Department of Medicine, San Francisco General Hospital, University of California
| | | | - Cristina Stoyanov
- Department of Medicine, San Francisco General Hospital, University of California
| | - Ijeoma Eccles-James
- Department of Medicine, San Francisco General Hospital, University of California
| | | | | | | | | | - Jessica Briggs
- Department of Medicine, San Francisco General Hospital, University of California
| | - Katherine Bowen
- Department of Medicine, San Francisco General Hospital, University of California
| | | | | | - Moses R Kamya
- Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California
| | - Margaret E Feeney
- Department of Medicine, San Francisco General Hospital, University of California Department of Pediatrics, University of California, San Francisco
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507
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da Costa M, Pinheiro-Silva R, Antunes S, Moreno-Cid JA, Custódio A, Villar M, Silveira H, de la Fuente J, Domingos A. Mosquito Akirin as a potential antigen for malaria control. Malar J 2014; 13:470. [PMID: 25472895 PMCID: PMC4265507 DOI: 10.1186/1475-2875-13-470] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 11/27/2014] [Indexed: 11/10/2022] Open
Abstract
Background The control of vector-borne diseases is important to improve human and animal health worldwide. Malaria is one of the world’s deadliest diseases and is caused by protozoan parasites of the genus Plasmodium, which are transmitted by Anopheles spp. mosquitoes. Recent evidences using Subolesin (SUB) and Akirin (AKR) vaccines showed a reduction in the survival and/or fertility of blood-sucking ectoparasite vectors and the infection with vector-borne pathogens. These experiments suggested the possibility of using AKR for malaria control. Methods The role of AKR on Plasmodium berghei infection and on the fitness and reproduction of the main malaria vector, Anopheles gambiae was characterized by evaluating the effect of akr gene knockdown or vaccination with recombinant mosquito AKR on parasite infection levels, fertility and mortality of female mosquitoes. Results Gene knockdown by RNA interference in mosquitoes suggested a role for akr in mosquito survival and fertility. Vaccination with recombinant Aedes albopictus AKR reduced parasite infection in mosquitoes fed on immunized mice when compared to controls. Conclusions These results showed that recombinant AKR could be used to develop vaccines for malaria control. If effective, AKR-based vaccines could be used to immunize wildlife reservoir hosts and/or humans to reduce the risk of pathogen transmission. However, these vaccines need to be evaluated under field conditions to characterize their effect on vector populations and pathogen infection and transmission.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ana Domingos
- Instituto de Higiene e Medicina Tropical, Rua da Junqueira 100, 1349-008 Lisbon, Portugal.
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508
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Ferguson DJP, Balaban AE, Patzewitz EM, Wall RJ, Hopp CS, Poulin B, Mohmmed A, Malhotra P, Coppi A, Sinnis P, Tewari R. The repeat region of the circumsporozoite protein is critical for sporozoite formation and maturation in Plasmodium. PLoS One 2014; 9:e113923. [PMID: 25438048 PMCID: PMC4250072 DOI: 10.1371/journal.pone.0113923] [Citation(s) in RCA: 32] [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: 09/03/2014] [Accepted: 10/31/2014] [Indexed: 11/25/2022] Open
Abstract
The circumsporozoite protein (CSP) is the major surface protein of the sporozoite stage of malaria parasites and has multiple functions as the parasite develops and then migrates from the mosquito midgut to the mammalian liver. The overall structure of CSP is conserved among Plasmodium species, consisting of a species-specific central tandem repeat region flanked by two conserved domains: the NH2-terminus and the thrombospondin repeat (TSR) at the COOH-terminus. Although the central repeat region is an immunodominant B-cell epitope and the basis of the only candidate malaria vaccine in Phase III clinical trials, little is known about its functional role(s). We used the rodent malaria model Plasmodium berghei to investigate the role of the CSP tandem repeat region during sporozoite development. Here we describe two mutant parasite lines, one lacking the tandem repeat region (ΔRep) and the other lacking the NH2-terminus as well as the repeat region (ΔNΔRep). We show that in both mutant lines oocyst formation is unaffected but sporozoite development is defective.
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Affiliation(s)
- David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
| | - Amanda E. Balaban
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Eva-Maria Patzewitz
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG2 7UH, United Kingdom
| | - Richard J. Wall
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG2 7UH, United Kingdom
| | - Christine S. Hopp
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Benoit Poulin
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG2 7UH, United Kingdom
| | - Asif Mohmmed
- International Centre for Genetic Engineering and Biotechnology, New Delhi-110067, India
| | - Pawan Malhotra
- International Centre for Genetic Engineering and Biotechnology, New Delhi-110067, India
| | - Alida Coppi
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Photini Sinnis
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail: (RT); (PS)
| | - Rita Tewari
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG2 7UH, United Kingdom
- * E-mail: (RT); (PS)
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509
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Abstract
Despite global efforts to control malaria, the illness remains a significant public health threat. Currently, there is no licensed vaccine against malaria, but an efficacious vaccine would represent an important public health tool for successful malaria elimination. Malaria vaccine development continues to be hindered by a poor understanding of antimalarial immunity, a lack of an immune correlate of protection, and the genetic diversity of malaria parasites. Current vaccine development efforts largely target Plasmodium falciparum parasites in the pre-erythrocytic and erythrocytic stages, with some research on transmission-blocking vaccines against asexual stages and vaccines against pregnancy-associated malaria. The leading pre-erythrocytic vaccine candidate is RTS,S, and early results of ongoing Phase 3 testing show overall efficacy of 46% against clinical malaria. The next steps for malaria vaccine development will focus on the design of a product that is efficacious against the highly diverse strains of malaria and the identification of a correlate of protection against disease.
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Affiliation(s)
- Amed Ouattara
- Department of Medicine, Center for Vaccine Development
| | - Matthew B Laurens
- Departments of Pediatrics and of Medicine, Howard Hughes Medical Institute / Center for Vaccine Development, University of Maryland School of Medicine, Baltimore
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510
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Torres MDT, Silva AF, de Souza Silva L, de Sá Pinheiro AA, Oliveira VXJ. Angiotensin II restricted analogs with biological activity in the erythrocytic cycle of Plasmodium falciparum. J Pept Sci 2014; 21:24-8. [DOI: 10.1002/psc.2714] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 10/14/2014] [Accepted: 10/17/2014] [Indexed: 01/03/2023]
Affiliation(s)
| | - Adriana Farias Silva
- Centro de Ciências Naturais e Humanas; Universidade Federal do ABC; Santo André SP Brazil
| | - Leandro de Souza Silva
- Instituto de Biofísica Carlos Chagas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
| | - Ana Acácia de Sá Pinheiro
- Instituto de Biofísica Carlos Chagas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
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511
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van Schaijk BCL, Ploemen IHJ, Annoura T, Vos MW, Foquet L, van Gemert GJ, Chevalley-Maurel S, van de Vegte-Bolmer M, Sajid M, Franetich JF, Lorthiois A, Leroux-Roels G, Meuleman P, Hermsen CC, Mazier D, Hoffman SL, Janse CJ, Khan SM, Sauerwein RW. A genetically attenuated malaria vaccine candidate based on P. falciparum b9/slarp gene-deficient sporozoites. eLife 2014; 3. [PMID: 25407681 PMCID: PMC4273440 DOI: 10.7554/elife.03582] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 11/19/2014] [Indexed: 12/16/2022] Open
Abstract
A highly efficacious pre-erythrocytic stage vaccine would be an important tool for the control and elimination of malaria but is currently unavailable. High-level protection in humans can be achieved by experimental immunization with Plasmodium falciparum sporozoites attenuated by radiation or under anti-malarial drug coverage. Immunization with genetically attenuated parasites (GAP) would be an attractive alternative approach. In this study, we present data on safety and protective efficacy using sporozoites with deletions of two genes, that is the newly identified b9 and slarp, which govern independent and critical processes for successful liver-stage development. In the rodent malaria model, PbΔb9ΔslarpGAP was completely attenuated showing no breakthrough infections while efficiently inducing high-level protection. The human PfΔb9ΔslarpGAP generated without drug resistance markers were infective to human hepatocytes in vitro and to humanized mice engrafted with human hepatocytes in vivo but completely aborted development after infection. These findings support the clinical development of a PfΔb9ΔslarpSPZ vaccine. DOI:http://dx.doi.org/10.7554/eLife.03582.001 Vaccines commonly contain a weakened or dead version of a disease-causing microorganism, or its toxins, or surface proteins. These prime the immune system to rapidly recognize, respond to, and eliminate the actual infectious pathogen if later encountered. While vaccines are currently available to help prevent a large number of diseases, vaccines for many deadly diseases, including malaria, do not yet exist. Malaria is caused by a group of parasites called Plasmodium, which are transferred to humans by mosquitoes. While measures to control mosquito populations and prevent mosquito bites have helped to reduce the incidence of malaria in some countries, the number of people—and especially children—that die of malaria every year remains very high. When a mosquito carrying Plasmodium in its salivary glands bites a human, the parasite is injected into the human's bloodstream and travels to the liver. The parasite reproduces in the liver cells until there are so many of them that the cells rupture, and the parasites are released back into the bloodstream. Any mosquito that then feeds on the blood of the infected individual may also suck up the parasite. The parasite then goes through a further stage of development in the mosquito, eventually migrating to the salivary glands, from where the parasite can be transmitted into a new human host. Recent work in rodents suggests that genetically altered or weakened Plasmodium falciparum sporozoites—the form of the parasite found in mosquito saliva—could be used to vaccinate humans against malaria caused by this parasite species. Now, van Schaijk, Ploemen et al. evaluate whether a safe and effective vaccine could be made from sporozoites that lack two genes, called b9 and slarp, which are critical for the parasites to develop inside liver cells. When mice were injected with the modified sporozoites, their immune cells were able to detect the parasites and respond against them. The mice subsequently did not develop malaria when they were infected with normal, unmodified parasites. Furthermore, none of the mice contracted malaria from the modified sporozoites. The modified sporozoites behaved similarly in human liver cells: after invading these cells, the parasites were unable to develop. Clinical testing and further development are now needed to see if a successful malaria vaccine can be made from these sporozoites. DOI:http://dx.doi.org/10.7554/eLife.03582.002
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Affiliation(s)
- Ben C L van Schaijk
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Ivo H J Ploemen
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Takeshi Annoura
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Martijn W Vos
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Lander Foquet
- Center for Vaccinology, Ghent University and University Hospital, Ghent, Belgium
| | - Geert-Jan van Gemert
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | | | - Marga van de Vegte-Bolmer
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Mohammed Sajid
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Jean-Francois Franetich
- Centre d'Immunologie et des Maladies Infectieuses, Université Pierre et Marie Curie-Paris 6, Paris, France
| | - Audrey Lorthiois
- Centre d'Immunologie et des Maladies Infectieuses, Université Pierre et Marie Curie-Paris 6, Paris, France
| | - Geert Leroux-Roels
- Center for Vaccinology, Ghent University and University Hospital, Ghent, Belgium
| | - Philip Meuleman
- Center for Vaccinology, Ghent University and University Hospital, Ghent, Belgium
| | - Cornelius C Hermsen
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Dominique Mazier
- Centre d'Immunologie et des Maladies Infectieuses, Université Pierre et Marie Curie-Paris 6, Paris, France
| | | | - Chris J Janse
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Shahid M Khan
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Robert W Sauerwein
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
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512
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Abstract
Systems-level analysis of biological processes strives to comprehensively and quantitatively evaluate the interactions between the relevant molecular components over time, thereby enabling development of models that can be employed to ultimately predict behavior. Rapid development in measurement technologies (omics), when combined with the accessible nature of the cellular constituents themselves, is allowing the field of innate immunity to take significant strides toward this lofty goal. In this review, we survey exciting results derived from systems biology analyses of the immune system, ranging from gene regulatory networks to influenza pathogenesis and systems vaccinology.
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513
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Crompton PD, Moebius J, Portugal S, Waisberg M, Hart G, Garver LS, Miller LH, Barillas-Mury C, Pierce SK. Malaria immunity in man and mosquito: insights into unsolved mysteries of a deadly infectious disease. Annu Rev Immunol 2014; 32:157-87. [PMID: 24655294 DOI: 10.1146/annurev-immunol-032713-120220] [Citation(s) in RCA: 207] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Malaria is a mosquito-borne disease caused by parasites of the obligate intracellular Apicomplexa phylum the most deadly of which, Plasmodium falciparum, prevails in Africa. Malaria imposes a huge health burden on the world's most vulnerable populations, claiming the lives of nearly one million children and pregnant women each year. Although there is keen interest in eradicating malaria, we do not yet have the necessary tools to meet this challenge, including an effective malaria vaccine and adequate vector control strategies. Here we review what is known about the mechanisms at play in immune resistance to malaria in both the human and mosquito hosts at each step in the parasite's complex life cycle with a view toward developing the tools that will contribute to the prevention of disease and death and, ultimately, to the goal of malaria eradication. In so doing, we hope to inspire immunologists to participate in defeating this devastating disease.
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514
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Dups JN, Pepper M, Cockburn IA. Antibody and B cell responses to Plasmodium sporozoites. Front Microbiol 2014; 5:625. [PMID: 25477870 PMCID: PMC4235289 DOI: 10.3389/fmicb.2014.00625] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 11/03/2014] [Indexed: 11/18/2022] Open
Abstract
Antibodies are capable of blocking infection of the liver by Plasmodium sporozoites. Accordingly the induction of anti-sporozoite antibodies is a major aim of various vaccine approaches to malaria. In recent years our knowledge of the specificity and quantities of antibodies required for protection has been greatly expanded by clinical trials of various whole sporozoite and subunit vaccines. Moreover, the development of humanized mouse models and transgenic parasites have also aided our ability to assess the specificity of antibodies and their ability to block infection. Nonetheless, considerable gaps remain in our knowledge – in particular in understanding what antigens are recognized by infection blocking antibodies and in knowing how we can induce robust, long-lived antibody responses. Maintaining high levels of circulating antibodies is likely to be of primary importance, as antibodies must block infection in the short time it takes for sporozoites to reach the liver from the skin. It is clear that a better understanding of the development of protective B cell-mediated immunity will aid the development and refinement of malaria vaccines.
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Affiliation(s)
- Johanna N Dups
- Department of Pathogens and Immunity, John Curtin School of Medical Research, Australian National University Canberra, ACT, Australia
| | - Marion Pepper
- Department of Immunology, School of Medicine, University of Washington Seattle, WA, USA
| | - Ian A Cockburn
- Department of Pathogens and Immunity, John Curtin School of Medical Research, Australian National University Canberra, ACT, Australia
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515
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Chia WN, Goh YS, Rénia L. Novel approaches to identify protective malaria vaccine candidates. Front Microbiol 2014; 5:586. [PMID: 25452745 PMCID: PMC4233905 DOI: 10.3389/fmicb.2014.00586] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/17/2014] [Indexed: 12/17/2022] Open
Abstract
Efforts to develop vaccines against malaria have been the focus of substantial research activities for decades. Several categories of candidate vaccines are currently being developed for protection against malaria, based on antigens corresponding to the pre-erythrocytic, blood stage, or sexual stages of the parasite. Long lasting sterile protection from Plasmodium falciparum sporozoite challenge has been observed in human following vaccination with whole parasite formulations, clearly demonstrating that a protective immune response targeting predominantly the pre-erythrocytic stages can develop against malaria. However, most of vaccine candidates currently being investigated, which are mostly subunits vaccines, have not been able to induce substantial (>50%) protection thus far. This is due to the fact that the antigens responsible for protection against the different parasite stages are still yet to be known and relevant correlates of protection have remained elusive. For a vaccine to be developed in a timely manner, novel approaches are required. In this article, we review the novel approaches that have been developed to identify the antigens for the development of an effective malaria vaccine.
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Affiliation(s)
- Wan Ni Chia
- Singapore Immunology Network, Agency for Science, Technology and Research Singapore, Singapore ; Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore Singapore, Singapore
| | - Yun Shan Goh
- Singapore Immunology Network, Agency for Science, Technology and Research Singapore, Singapore
| | - Laurent Rénia
- Singapore Immunology Network, Agency for Science, Technology and Research Singapore, Singapore ; Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore Singapore, Singapore
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516
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Bijker EM, Schats R, Obiero JM, Behet MC, van Gemert GJ, van de Vegte-Bolmer M, Graumans W, van Lieshout L, Bastiaens GJH, Teelen K, Hermsen CC, Scholzen A, Visser LG, Sauerwein RW. Sporozoite immunization of human volunteers under mefloquine prophylaxis is safe, immunogenic and protective: a double-blind randomized controlled clinical trial. PLoS One 2014; 9:e112910. [PMID: 25396417 PMCID: PMC4232459 DOI: 10.1371/journal.pone.0112910] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 10/14/2014] [Indexed: 11/30/2022] Open
Abstract
Immunization of healthy volunteers with chloroquine ChemoProphylaxis and Sporozoites (CPS-CQ) efficiently and reproducibly induces dose-dependent and long-lasting protection against homologous Plasmodium falciparum challenge. Here, we studied whether chloroquine can be replaced by mefloquine, which is the only other licensed anti-malarial chemoprophylactic drug that does not affect pre-erythrocytic stages, exposure to which is considered essential for induction of protection by CPS immunization. In a double blind randomized controlled clinical trial, volunteers under either chloroquine prophylaxis (CPS-CQ, n = 5) or mefloquine prophylaxis (CPS-MQ, n = 10) received three sub-optimal CPS immunizations by bites from eight P. falciparum infected mosquitoes each, at monthly intervals. Four control volunteers received mefloquine prophylaxis and bites from uninfected mosquitoes. CPS-MQ immunization is safe and equally potent compared to CPS-CQ inducing protection in 7/10 (70%) versus 3/5 (60%) volunteers, respectively. Furthermore, specific antibody levels and cellular immune memory responses were comparable between both groups. We therefore conclude that mefloquine and chloroquine are equally effective in CPS-induced immune responses and protection. Trial Registration ClinicalTrials.gov NCT01422954
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Affiliation(s)
- Else M. Bijker
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Remko Schats
- Leiden University Medical Center, Department of Infectious Diseases, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Joshua M. Obiero
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Marije C. Behet
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Geert-Jan van Gemert
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Marga van de Vegte-Bolmer
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Wouter Graumans
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Lisette van Lieshout
- Leiden University Medical Center, Department of Medical Microbiology, PO Box 9600, 2300 RC Leiden, The Netherlands
- Leiden University Medical Center, Department of Parasitology, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Guido J. H. Bastiaens
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Karina Teelen
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Cornelus C. Hermsen
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Anja Scholzen
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Leo G. Visser
- Leiden University Medical Center, Department of Infectious Diseases, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Robert W. Sauerwein
- Radboud university medical center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands
- * E-mail:
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517
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A replicating adenovirus capsid display recombinant elicits antibodies against Plasmodium falciparum sporozoites in Aotus nancymaae monkeys. Infect Immun 2014; 83:268-75. [PMID: 25368113 DOI: 10.1128/iai.02626-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Decades of success with live adenovirus vaccines suggest that replication-competent recombinant adenoviruses (rAds) could serve as effective vectors for immunization against other pathogens. To explore the potential of a live rAd vaccine against malaria, we prepared a viable adenovirus 5 (Ad5) recombinant that displays a B-cell epitope from the circumsporozoite protein (CSP) of Plasmodium falciparum on the virion surface. The recombinant induced P. falciparum sporozoite-neutralizing antibodies in mice. Human adenoviruses do not replicate in mice. Therefore, to examine immunogenicity in a system in which, as in humans, the recombinant replicates, we constructed a similar recombinant in an adenovirus mutant that replicates in monkey cells and immunized four Aotus nancymaae monkeys. The recombinant replicated in the monkeys after intratracheal instillation, the first demonstration of replication of human adenoviruses in New World monkeys. Immunization elicited antibodies both to the Plasmodium epitope and the Ad5 vector. Antibodies from all four monkeys recognized CSP on intact parasites, and plasma from one monkey neutralized sporozoites in vitro and conferred partial protection against P. falciparum sporozoite infection after passive transfer to mice. Prior enteric inoculation of two animals with antigenically wild-type adenovirus primed a response to the subsequent intratracheal inoculation, suggesting a route to optimizing performance. A vaccine is not yet available against P. falciparum, which induces the deadliest form of malaria and kills approximately one million children each year. The live capsid display recombinant described here may constitute an early step in a critically needed novel approach to malaria immunization.
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518
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Moncunill G, Han H, Dobaño C, McElrath MJ, De Rosa SC. OMIP-024: pan-leukocyte immunophenotypic characterization of PBMC subsets in human samples. Cytometry A 2014; 85:995-8. [PMID: 25352070 DOI: 10.1002/cyto.a.22580] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 10/06/2014] [Indexed: 01/22/2023]
Affiliation(s)
- Gemma Moncunill
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, 98109; Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Catalonia, Spain
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519
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Gazzinelli RT, Kalantari P, Fitzgerald KA, Golenbock DT. Innate sensing of malaria parasites. Nat Rev Immunol 2014; 14:744-57. [PMID: 25324127 DOI: 10.1038/nri3742] [Citation(s) in RCA: 207] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Innate immune receptors have a key role in immune surveillance by sensing microorganisms and initiating protective immune responses. However, the innate immune system is a classic 'double-edged sword' that can overreact to pathogens, which can have deleterious effects and lead to clinical manifestations. Recent studies have unveiled the complexity of innate immune receptors that function as sensors of Plasmodium spp. in the vertebrate host. This Review highlights the cellular and molecular mechanisms by which Plasmodium infection is sensed by different families of innate immune receptors. We also discuss how these events mediate both host resistance to infection and the pathogenesis of malaria.
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Affiliation(s)
- Ricardo T Gazzinelli
- 1] Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, 01605-02324 Worcester, Massachusetts, USA. [2] Laboratório de Imunopatologia, Centro de Pesquisa René Rachou, Fundação Oswaldo Cruz, 30190-002 Belo Horizonte, Minas Gerais, Brazil. [3] Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Parisa Kalantari
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, 01605-02324 Worcester, Massachusetts, USA
| | - Katherine A Fitzgerald
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, 01605-02324 Worcester, Massachusetts, USA
| | - Douglas T Golenbock
- 1] Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, 01605-02324 Worcester, Massachusetts, USA. [2] Laboratório de Imunopatologia, Centro de Pesquisa René Rachou, Fundação Oswaldo Cruz, 30190-002 Belo Horizonte, Minas Gerais, Brazil
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520
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Krzych U, Zarling S, Pichugin A. Memory T cells maintain protracted protection against malaria. Immunol Lett 2014; 161:189-95. [PMID: 24709142 PMCID: PMC6499475 DOI: 10.1016/j.imlet.2014.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 03/25/2014] [Accepted: 03/27/2014] [Indexed: 10/25/2022]
Abstract
Immunologic memory is one of the cardinal features of antigen-specific immune responses, and the persistence of memory cells contributes to prophylactic immunizations against infectious agents. Adequately maintained memory T and B cell pools assure a fast, effective and specific response against re-infections. However, many aspects of immunologic memory are still poorly understood, particularly immunologic memory inducible by parasites, for example, Plasmodium spp., the causative agents of malaria. For example, memory responses to Plasmodium antigens amongst residents of malaria endemic areas appear to be either inadequately developed or maintained, because persons who survive episodes of childhood malaria remain vulnerable to intermittent malaria infections. By contrast, multiple exposures of humans and laboratory rodents to radiation-attenuated Plasmodium sporozoites (γ-spz) induce sterile and long-lasting protection against experimental sporozoite challenge. Multifactorial immune mechanisms maintain this protracted and sterile protection. While the presence of memory CD4 T cell subsets has been associated with lasting protection in humans exposed to multiple bites from Anopheles mosquitoes infected with attenuated Plasmodium falciparum, memory CD8 T cells maintain protection induced with Plasmodium yoelii and Plasmodium berghei γ-spz in murine models. In this review, we discuss our observations that show memory CD8 T cells specific for antigens expressed by P. berghei liver stage parasites as an indispensable component for the maintenance of protracted protective immunity against experimental malaria infection; moreover, the provision of an Ag-depot assures a quick recall of memory T cells as IFN-γ-producing effector CD8 T cells and IL-4- producing CD4 T cells that collaborate with B cells for an effective antibody response.
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Affiliation(s)
- Urszula Krzych
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States.
| | - Stasya Zarling
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Alexander Pichugin
- Department of Cellular Immunology, Branch of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
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521
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Immunization of mice with live-attenuated late liver stage-arresting Plasmodium yoelii parasites generates protective antibody responses to preerythrocytic stages of malaria. Infect Immun 2014; 82:5143-53. [PMID: 25267837 DOI: 10.1128/iai.02320-14] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Understanding protective immunity to malaria is essential for the design of an effective vaccine to prevent the large number of infections and deaths caused by this parasitic disease. To date, whole-parasite immunization with attenuated parasites is the most effective method to confer sterile protection against malaria infection in clinical trials. Mouse model studies have highlighted the essential role that CD8(+) T cells play in protection against preerythrocytic stages of malaria; however, there is mounting evidence that antibodies are also important in these stages. Here, we show that experimental immunization of mice with Plasmodium yoelii fabb/f(-) (Pyfabb/f(-)), a genetically attenuated rodent malaria parasite that arrests late in the liver stage, induced functional antibodies that inhibited hepatocyte invasion in vitro and reduced liver-stage burden in vivo. These antibodies were sufficient to induce sterile protection from challenge by P. yoelii sporozoites in the absence of T cells in 50% of mice when sporozoites were administered by mosquito bite but not when they were administered by intravenous injection. Moreover, among mice challenged by mosquito bite, a higher proportion of BALB/c mice than C57BL/6 mice developed sterile protection (62.5% and 37.5%, respectively). Analysis of the antibody isotypes induced by immunization with Pyfabb/f(-) showed that, overall, BALB/c mice developed an IgG1-biased response, whereas C57BL/6 mice developed an IgG2b/c-biased response. Our data demonstrate for the first time that antibodies induced by experimental immunization of mice with a genetically attenuated rodent parasite play a protective role during the preerythrocytic stages of malaria. Furthermore, they highlight the importance of considering both the route of challenge and the genetic background of the mouse strains used when interpreting vaccine efficacy studies in animal models of malaria infection.
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522
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Targett G. Phase 3 trial with the RTS,S/AS01 malaria vaccine shows protection against clinical and severe malaria in infants and children in Africa. ACTA ACUST UNITED AC 2014; 20:9. [PMID: 25228673 DOI: 10.1136/ebmed-2014-110089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Geoffrey Targett
- Faculty of Infectious and Tropical Diseases, Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
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523
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Sedegah M, Hollingdale MR, Farooq F, Ganeshan H, Belmonte M, Kim Y, Peters B, Sette A, Huang J, McGrath S, Abot E, Limbach K, Shi M, Soisson L, Diggs C, Chuang I, Tamminga C, Epstein JE, Villasante E, Richie TL. Sterile immunity to malaria after DNA prime/adenovirus boost immunization is associated with effector memory CD8+T cells targeting AMA1 class I epitopes. PLoS One 2014; 9:e106241. [PMID: 25211344 PMCID: PMC4161338 DOI: 10.1371/journal.pone.0106241] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 07/29/2014] [Indexed: 11/24/2022] Open
Abstract
Background Fifteen volunteers were immunized with three doses of plasmid DNA encoding P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1) and boosted with human adenovirus-5 (Ad) expressing the same antigens (DNA/Ad). Four volunteers (27%) demonstrated sterile immunity to controlled human malaria infection and, overall, protection was statistically significantly associated with ELISpot and CD8+ T cell IFN-γ activities to AMA1 but not CSP. DNA priming was required for protection, as 18 additional subjects immunized with Ad alone (AdCA) did not develop sterile protection. Methodology/Principal Findings We sought to identify correlates of protection, recognizing that DNA-priming may induce different responses than AdCA alone. Among protected volunteers, two and three had higher ELISpot and CD8+ T cell IFN-γ responses to CSP and AMA1, respectively, than non-protected volunteers. Unexpectedly, non-protected volunteers in the AdCA trial showed ELISpot and CD8+ T cell IFN-γ responses to AMA1 equal to or higher than the protected volunteers. T cell functionality assessed by intracellular cytokine staining for IFN-γ, TNF-α and IL-2 likewise did not distinguish protected from non-protected volunteers across both trials. However, three of the four protected volunteers showed higher effector to central memory CD8+ T cell ratios to AMA1, and one of these to CSP, than non-protected volunteers for both antigens. These responses were focused on discrete regions of CSP and AMA1. Class I epitopes restricted by A*03 or B*58 supertypes within these regions of AMA1 strongly recalled responses in three of four protected volunteers. We hypothesize that vaccine-induced effector memory CD8+ T cells recognizing a single class I epitope can confer sterile immunity to P. falciparum in humans. Conclusions/Significance We suggest that better understanding of which epitopes within malaria antigens can confer sterile immunity and design of vaccine approaches that elicit responses to these epitopes will increase the potency of next generation gene-based vaccines.
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Affiliation(s)
- Martha Sedegah
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- * E-mail:
| | - Michael R. Hollingdale
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Fouzia Farooq
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Harini Ganeshan
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Maria Belmonte
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Yohan Kim
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Bjoern Peters
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Jun Huang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Shannon McGrath
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Esteban Abot
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Keith Limbach
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Meng Shi
- Division of Medical, Audio, Visual, Library and Statistical Services, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | | | - Ilin Chuang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Cindy Tamminga
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Judith E. Epstein
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Eileen Villasante
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Thomas L. Richie
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
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524
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Doolan DL, Apte SH, Proietti C. Genome-based vaccine design: the promise for malaria and other infectious diseases. Int J Parasitol 2014; 44:901-13. [PMID: 25196370 DOI: 10.1016/j.ijpara.2014.07.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 07/30/2014] [Accepted: 07/31/2014] [Indexed: 01/08/2023]
Abstract
Vaccines are one of the most effective interventions to improve public health, however, the generation of highly effective vaccines for many diseases has remained difficult. Three chronic diseases that characterise these difficulties include malaria, tuberculosis and HIV, and they alone account for half of the global infectious disease burden. The whole organism vaccine approach pioneered by Jenner in 1796 and refined by Pasteur in 1857 with the "isolate, inactivate and inject" paradigm has proved highly successful for many viral and bacterial pathogens causing acute disease but has failed with respect to malaria, tuberculosis and HIV as well as many other diseases. A significant advance of the past decade has been the elucidation of the genomes, proteomes and transcriptomes of many pathogens. This information provides the foundation for new 21st Century approaches to identify target antigens for the development of vaccines, drugs and diagnostic tests. Innovative genome-based vaccine strategies have shown potential for a number of challenging pathogens, including malaria. We advocate that genome-based rational vaccine design will overcome the problem of poorly immunogenic, poorly protective vaccines that has plagued vaccine developers for many years.
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Affiliation(s)
- Denise L Doolan
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029, Australia.
| | - Simon H Apte
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029, Australia
| | - Carla Proietti
- Infectious Diseases Programme, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029, Australia
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525
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AAV8-mediated in vivo overexpression of miR-155 enhances the protective capacity of genetically attenuated malarial parasites. Mol Ther 2014; 22:2130-2141. [PMID: 25189739 DOI: 10.1038/mt.2014.172] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 08/25/2014] [Indexed: 12/17/2022] Open
Abstract
Malaria, caused by protozoan Plasmodium parasites, remains a prevalent infectious human disease due to the lack of an efficient and safe vaccine. This is directly related to the persisting gaps in our understanding of the parasite's interactions with the infected host, especially during the clinically silent yet essential liver stage of Plasmodium development. Previously, we and others showed that genetically attenuated parasites (GAP) that arrest in the liver induce sterile immunity, but only upon multiple administrations. Here, we comprehensively studied hepatic gene and miRNA expression in GAP-injected mice, and found both a broad activation of IFNγ-associated pathways and a significant increase of murine microRNA-155 (miR-155), that was especially pronounced in non-parenchymal cells including liver-resident macrophages (Kupffer cells). Remarkably, ectopic upregulation of this miRNA in the liver of mice using robust hepatotropic adeno-associated virus 8 (AAV8) vectors enhanced GAP's protective capacity substantially. In turn, this AAV8-mediated miR-155 expression permitted a reduction of GAP injections needed to achieve complete protection against infectious parasite challenge from previously three to only one. Our study highlights a crucial role of mammalian miRNAs in Plasmodium liver infection in vivo and concurrently implies their great potential as future immune-augmenting agents in improved vaccination regimes against malaria and other diseases.
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526
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Billingsley P, Sim BKL, James E, Richie T, Shekalaghe S, Healy S, Sissoko M, Mordmueller B, Ledgerwood J, Graham B, Duffy P, Seder R, Lyke K, Epstein J, Alonso P, Abdullah S, Duombo O, Kremsner P, Tanner M, Hoffman S. Progress with PfSPZ Vaccine, a radiation attenuated Plasmodium falciparum sporozoite vaccine. Malar J 2014. [PMCID: PMC4179253 DOI: 10.1186/1475-2875-13-s1-o34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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527
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Morrot A, Rodrigues MM. Tissue signatures influence the activation of intrahepatic CD8(+) T cells against malaria sporozoites. Front Microbiol 2014; 5:440. [PMID: 25202304 PMCID: PMC4141441 DOI: 10.3389/fmicb.2014.00440] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 08/03/2014] [Indexed: 11/19/2022] Open
Abstract
Plasmodium sporozoites and liver stages express antigens that are targeted to the MHC-Class I antigen-processing pathway. After the introduction of Plasmodium sporozoites by Anopheles mosquitoes, bone marrow-derived dendritic cells in skin-draining lymph nodes are the first cells to cross-present parasite antigens and elicit specific CD8+ T cells. One of these antigens is the immunodominant circumsporozoite protein (CSP). The CD8+ T cell-mediated protective immune response against CSP is dependent on the interleukin loop involving IL-4 receptor expression on CD8+ cells and IL-4 secretion by CD4+ T cell helpers. In a few days, these CD8+ T cells re-circulate to secondary lymphoid organs and the liver. In the liver, the hepatic sinusoids are enriched with cells, such as dendritic, sinusoidal endothelial and Kupffer cells, that are able to cross-present MHC class I antigens to intrahepatic CD8+ T cells. Specific CD8+ T cells actively find infected hepatocytes and target intra-cellular parasites through mechanisms that are both interferon-γ-dependent and -independent. Immunity is mediated by CD8+ T effector or effector-memory cells and, when present in high numbers, these cells can provide sterilizing immunity. Human vaccination trials with recombinant formulations or attenuated sporozoites have yet to achieve the high numbers of specific effector T cells that are required for sterilizing immunity. In spite of the limited number of specific CD8+ T cells, attenuated sporozoites provided multiple times by the endovenous route provided a high degree of protective immunity. These observations highlight that CD8+ T cells may be useful for improving antibody-mediated protective immunity to pre-erythrocytic stages of malaria parasites.
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Affiliation(s)
- Alexandre Morrot
- Departamento de Imunologia, Instituro de Microbiologia, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
| | - Maurício M Rodrigues
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina São Paulo, Brazil
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528
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Circumsporozoite protein-specific K(d)-restricted CD8+ T cells mediate protective antimalaria immunity in sporozoite-immunized MHC-I-K(d) transgenic mice. Mediators Inflamm 2014; 2014:728939. [PMID: 25132735 PMCID: PMC4124204 DOI: 10.1155/2014/728939] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/23/2014] [Indexed: 11/28/2022] Open
Abstract
Although the roles of CD8+ T cells and a major preerythrocytic antigen, the circumsporozoite (CS) protein, in contributing protective antimalaria immunity induced by radiation-attenuated sporozoites, have been shown by a number of studies, the extent to which these players contribute to antimalaria immunity is still unknown. To address this question, we have generated C57BL/6 (B6) transgenic (Tg) mice, expressing Kd molecules under the MHC-I promoter, called MHC-I-Kd-Tg mice. In this study, we first determined that a single immunizing dose of IrPySpz induced a significant level of antimalaria protective immunity in MHC-I-Kd-Tg mice but not in B6 mice. Then, by depleting various T-cell subsets in vivo, we determined that CD8+ T cells are the main mediator of the protective immunity induced by IrPySpz. Furthermore, when we immunized (MHC-I-Kd-Tg × CS-Tg) F1 mice with IrPySpz after crossing MHC-I-Kd-Tg mice with PyCS-transgenic mice (CS-Tg), which are unable to mount PyCS-specific immunity, we found that IrPySpz immunization failed to induce protective antimalaria immunity in (MHC-I-Kd-Tg × CS-Tg) F1 mice, thus indicating the absence of PyCS antigen-dependent immunity in these mice. These results indicate that protective antimalaria immunity induced by IrPySpz in MHC-I-Kd-Tg mice is mediated by CS protein-specific, Kd-restricted CD8+ T cells.
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529
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Vectored antibody gene delivery protects against Plasmodium falciparum sporozoite challenge in mice. Proc Natl Acad Sci U S A 2014; 111:12528-32. [PMID: 25114213 DOI: 10.1073/pnas.1407362111] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Malaria caused by Plasmodium falciparum kills nearly one million children each year and imposes crippling economic burdens on families and nations worldwide. No licensed vaccine exists, but infection can be prevented by antibodies against the circumsporozoite protein (CSP), the major surface protein of sporozoites, the form of the parasite injected by mosquitoes. We have used vectored immunoprophylaxis (VIP), an adeno-associated virus-based technology, to introduce preformed antibody genes encoding anti-P. falciparum CSP mAb into mice. VIP vector-transduced mice exhibited long-lived mAb expression at up to 1,200 µg/mL in serum, and up to 70% were protected from both i.v. and mosquito bite challenge with transgenic Plasmodium berghei rodent sporozoites that incorporate the P. falciparum target of the mAb in their CSP. Serum antibody levels and protection from mosquito bite challenge were dependent on the dose of the VIP vector. All individual mice expressing CSP-specific mAb 2A10 at 1 mg/mL or more were completely protected, suggesting that in this model system, exceeding that threshold results in consistent sterile protection. Our results demonstrate the potential of VIP as a path toward the elusive goal of immunization against malaria.
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530
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Abstract
Protective immunity against preerythrocytic malaria parasite infection is difficult to achieve. Intracellular Plasmodium parasites likely minimize antigen presentation by surface-expressed major histocompatibility complex class I (MHC-I) molecules on infected cells, yet they actively remodel their host cells by export of parasite factors. Whether exported liver-stage proteins constitute better candidates for MHC-I antigen presentation to CD8+ T lymphocytes remains unknown. Here, we systematically characterized the contribution of protein export to the magnitude of antigen-specific T-cell responses against Plasmodium berghei liver-stage parasites in C57BL/6 mice. We generated transgenic sporozoites that secrete a truncated ovalbumin (OVA) surrogate antigen only in the presence of an amino-terminal protein export element. Immunization with live attenuated transgenic sporozoites revealed that antigen export was not critical for CD8+ T-cell priming but enhanced CD8+ T-cell proliferation in the liver. Upon transfer of antigen-specific CD8+ T cells, liver-stage parasites secreting the target protein were eliminated more efficiently. We conclude that Plasmodium parasites strictly control protein export during liver infection to minimize immune recognition. Strategies that enhance the discharge of parasite proteins into infected hepatocytes could improve the efficacy of candidate preerythrocytic malaria vaccines. Vaccine development against Plasmodium parasites remains a priority in malaria research. The most advanced malaria subunit vaccine candidates contain Plasmodium surface proteins with important roles for parasite vital functions. A fundamental question is whether recognition by effector CD8+ T cells is restricted to sporozoite surface antigens or extends to parasite proteins that are synthesized during the extensive parasite expansion phase in the liver. Using a surrogate model antigen, we found that a cytoplasmic antigen is able to induce robust protective CD8+ T-cell responses, but protein export further enhances immunogenicity and protection. Our results show that a cytoplasmic localization does not exclude a protein’s candidacy for malaria subunit vaccines and that protein secretion can enhance protective immunity.
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531
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Good MF. The ability to inoculate purified malaria sporozoites will accelerate vaccine and drug discovery. Am J Trop Med Hyg 2014; 91:437-438. [PMID: 25070994 PMCID: PMC4155540 DOI: 10.4269/ajtmh.14-0395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Michael F. Good
- *Address correspondence to Michael F. Good, G26, 4.18, Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia 4222. E-mail:
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532
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Shekalaghe S, Rutaihwa M, Billingsley PF, Chemba M, Daubenberger CA, James ER, Mpina M, Ali Juma O, Schindler T, Huber E, Gunasekera A, Manoj A, Simon B, Saverino E, Church LWP, Hermsen CC, Sauerwein RW, Plowe C, Venkatesan M, Sasi P, Lweno O, Mutani P, Hamad A, Mohammed A, Urassa A, Mzee T, Padilla D, Ruben A, Lee Sim BK, Tanner M, Abdulla S, Hoffman SL. Controlled human malaria infection of Tanzanians by intradermal injection of aseptic, purified, cryopreserved Plasmodium falciparum sporozoites. Am J Trop Med Hyg 2014; 91:471-480. [PMID: 25070995 PMCID: PMC4155546 DOI: 10.4269/ajtmh.14-0119] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Controlled human malaria infection (CHMI) by mosquito bite has been used to assess anti-malaria interventions in > 1,500 volunteers since development of methods for infecting mosquitoes by feeding on Plasmodium falciparum (Pf) gametocyte cultures. Such CHMIs have never been used in Africa. Aseptic, purified, cryopreserved Pf sporozoites, PfSPZ Challenge, were used to infect Dutch volunteers by intradermal injection. We conducted a double-blind, placebo-controlled trial to assess safety and infectivity of PfSPZ Challenge in adult male Tanzanians. Volunteers were injected intradermally with 10,000 (N = 12) or 25,000 (N = 12) PfSPZ or normal saline (N = 6). PfSPZ Challenge was well tolerated and safe. Eleven of 12 and 10 of 11 subjects, who received 10,000 and 25,000 PfSPZ respectively, developed parasitemia. In 10,000 versus 25,000 PfSPZ groups geometric mean days from injection to Pf positivity by thick blood film was 15.4 versus 13.5 (P = 0.023). Alpha-thalassemia heterozygosity had no apparent effect on infectivity. PfSPZ Challenge was safe, well tolerated, and infectious.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Stephen L. Hoffman
- *Address correspondence to Stephen L. Hoffman, Sanaria Inc., 9800 Medical Center Drive, Rockville, MD 20850. E-mail:
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533
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Chen L, Keitany GJ, Peng X, Gibson C, Mohar I, Vignali M, Crispe IN, Huang F, Wang R. Identification of pre-erythrocytic malaria antigens that target hepatocytes for killing in vivo and contribute to protection elicited by whole-parasite vaccination. PLoS One 2014; 9:e102225. [PMID: 25025375 PMCID: PMC4099202 DOI: 10.1371/journal.pone.0102225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 06/17/2014] [Indexed: 11/19/2022] Open
Abstract
Pre-erythrocytic malaria vaccines, including those based on whole-parasite approaches, have shown protective efficacy in animal and human studies. However few pre-erythocytic antigens other than the immunodominant circumsporozoite protein (CSP) have been studied in depth with the goal of developing potent subunit malaria vaccines that are suited for use in endemic areas. Here we describe a novel technique to identify pre-erythrocytic malaria antigens that contribute to protection elicited by whole-parasite vaccination in the mouse model. Our approach combines immunization with genetically attenuated parasites and challenge with DNA plasmids encoding for potential protective pre-erythrocytic malaria antigens as luciferase fusions by hydrodynamic tail vein injection. After optimizing the technique, we first showed that immunization with Pyfabb/f−, a P. yoelii genetically attenuated parasite, induces killing of CSP-presenting hepatocytes. Depletion of CD8+ but not CD4+ T cells diminished the killing of CSP-expressing hepatocytes, indicating that killing is CD8+ T cell-dependent. Finally we showed that the use of heterologous prime/boost immunization strategies that use genetically attenuated parasites and DNA vaccines enabled the characterization of a novel pre-erythrocytic antigen, Tmp21, as a contributor to Pyfabb/f− induced protection. This technique will be valuable for identification of potentially protective liver stage antigens and has the potential to contribute to the understanding of immunity elicited by whole parasite vaccination, as well as the development of effective subunit malaria vaccines.
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Affiliation(s)
- Lin Chen
- Department of Pathogenic Biology, Third Military Medical University, Chongqing, China
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Gladys J. Keitany
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Xiaohong Peng
- Department of Pathogenic Biology, Third Military Medical University, Chongqing, China
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Claire Gibson
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Isaac Mohar
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
| | - Marissa Vignali
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Ian N. Crispe
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Department of Immunology, University of Washington, Seattle, Washington, United States of America
| | - Fusheng Huang
- Department of Pathogenic Biology, Third Military Medical University, Chongqing, China
- * E-mail: (FH); (RW)
| | - Ruobing Wang
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
- * E-mail: (FH); (RW)
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534
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Njoroge M, Njuguna NM, Mutai P, Ongarora DSB, Smith PW, Chibale K. Recent approaches to chemical discovery and development against malaria and the neglected tropical diseases human African trypanosomiasis and schistosomiasis. Chem Rev 2014; 114:11138-63. [PMID: 25014712 DOI: 10.1021/cr500098f] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | | | | | | | - Paul W Smith
- Novartis Institute for Tropical Diseases , Singapore 138670, Singapore
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535
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White MT, Bejon P, Olotu A, Griffin JT, Bojang K, Lusingu J, Salim N, Abdulla S, Otsyula N, Agnandji ST, Lell B, Asante KP, Owusu-Agyei S, Mahama E, Agbenyega T, Ansong D, Sacarlal J, Aponte JJ, Ghani AC. A combined analysis of immunogenicity, antibody kinetics and vaccine efficacy from phase 2 trials of the RTS,S malaria vaccine. BMC Med 2014; 12:117. [PMID: 25012228 PMCID: PMC4227280 DOI: 10.1186/s12916-014-0117-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/19/2014] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND The RTS,S malaria vaccine is currently undergoing phase 3 trials. High vaccine-induced antibody titres to the circumsporozoite protein (CSP) antigen have been associated with protection from infection and episodes of clinical malaria. METHODS Using data from 5,144 participants in nine phase 2 trials, we explore predictors of vaccine immunogenicity (anti-CSP antibody titres), decay in antibody titres, and the association between antibody titres and clinical outcomes. We use empirically-observed relationships between these factors to predict vaccine efficacy in a range of scenarios. RESULTS Vaccine-induced anti-CSP antibody titres were significantly associated with age (P = 0.04), adjuvant (P <0.001), pre-vaccination anti-hepatitis B surface antigen titres (P = 0.005) and pre-vaccination anti-CSP titres (P <0.001). Co-administration with other vaccines reduced anti-CSP antibody titres although not significantly (P = 0.095). Antibody titres showed a bi-phasic decay over time with an initial rapid decay in the first three months and a second slower decay over the next three to four years. Antibody titres were significantly associated with protection, with a titre of 51 (95% Credible Interval (CrI): 29 to 85) ELISA units/ml (EU/mL) predicted to prevent 50% of infections in children. Vaccine efficacy was predicted to decline to zero over four years in a setting with entomological inoculation rate (EIR) = 20 infectious bites per year (ibpy). Over a five-year follow-up period at an EIR = 20 ibpy, we predict RTS,S will avert 1,782 cases per 1,000 vaccinated children, 1,452 cases per 1,000 vaccinated infants, and 887 cases per 1,000 infants when co-administered with expanded programme on immunisation (EPI) vaccines. Our main study limitations include an absence of vaccine-induced cellular immune responses and short duration of follow-up in some individuals. CONCLUSIONS Vaccine-induced anti-CSP antibody titres and transmission intensity can explain variations in observed vaccine efficacy.
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536
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Chang KP. Vaccination for Disease Prevention and Control: the Necessity of Renewed Emphasis and New Approaches. ACTA ACUST UNITED AC 2014; 1. [PMID: 27840849 PMCID: PMC5103642 DOI: 10.17653/2374-9105.sse0001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Kwang Poo Chang
- Department of Microbiology/Immunology Chicago Medical School/Rosalind Franklin University of Medicine and Science, North Chicago, USA
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537
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Parra-López CA, Bernal-Estévez D, Vargas LE, Pulido-Calixto C, Salazar LM, Calvo-Calle JM, Stern LJ. An unstable Th epitope of P. falciparum fosters central memory T cells and anti-CS antibody responses. PLoS One 2014; 9:e100639. [PMID: 24983460 PMCID: PMC4077652 DOI: 10.1371/journal.pone.0100639] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 05/29/2014] [Indexed: 11/19/2022] Open
Abstract
Malaria is transmitted by Plasmodium-infected anopheles mosquitoes. Widespread resistance of mosquitoes to insecticides and resistance of parasites to drugs highlight the urgent need for malaria vaccines. The most advanced malaria vaccines target sporozoites, the infective form of the parasite. A major target of the antibody response to sporozoites are the repeat epitopes of the circumsporozoite (CS) protein, which span almost one half of the protein. Antibodies to these repeats can neutralize sporozoite infectivity. Generation of protective antibody responses to the CS protein (anti-CS Ab) requires help by CD4 T cells. A CD4 T cell epitope from the CS protein designated T* was previously identified by screening T cells from volunteers immunized with irradiated P. falciparum sporozoites. The T* sequence spans twenty amino acids that contains multiple T cell epitopes restricted by various HLA alleles. Subunit malaria vaccines including T* are highly immunogenic in rodents, non-human primates and humans. In this study we characterized a highly conserved HLA-DRβ1*04:01 (DR4) restricted T cell epitope (QNT-5) located at the C-terminus of T*. We found that a peptide containing QNT-5 was able to elicit long-term anti-CS Ab responses and prime CD4 T cells in HLA-DR4 transgenic mice despite forming relatively unstable MHC-peptide complexes highly susceptible to HLA-DM editing. We attempted to improve the immunogenicity of QNT-5 by replacing the P1 anchor position with an optimal tyrosine residue. The modified peptide QNT-Y formed stable MHC-peptide complexes highly resistant to HLA-DM editing. Contrary to expectations, a linear peptide containing QNT-Y elicited almost 10-fold lower long-term antibody and IFN-γ responses compared to the linear peptide containing the wild type QNT-5 sequence. Some possibilities regarding why QNT-5 is more effective than QNT-Y in inducing long-term T cell and anti-CS Ab when used as vaccine are discussed.
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Affiliation(s)
- Carlos A. Parra-López
- Department of Microbiology, School of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
- Graduate School in Biomedical Sciences, Universidad Nacional de Colombia, Bogotá, Colombia
- * E-mail: (CAP-L); (LJS)
| | - David Bernal-Estévez
- Department of Microbiology, School of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
- Graduate School in Biomedical Sciences, Universidad Nacional de Colombia, Bogotá, Colombia
- Fundación Salud de los Andes, Research Group of Immunology and Clinical Oncology - GIIOC, Bogotá, Colombia
| | - Luis Eduardo Vargas
- Department of Microbiology, School of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Carolina Pulido-Calixto
- Department of Microbiology, School of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Luz Mary Salazar
- Faculty of Sciences, Universidad Nacional de Colombia, Bogotá, Colombia
| | - J. Mauricio Calvo-Calle
- University of Massachusetts Medical School, Department of Pathology and Biochemistry and the Department of Molecular Pharmacology, Worcester, Massachusetts, United States of America
| | - Lawrence J. Stern
- University of Massachusetts Medical School, Department of Pathology and Biochemistry and the Department of Molecular Pharmacology, Worcester, Massachusetts, United States of America
- * E-mail: (CAP-L); (LJS)
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538
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De Gregorio E, Rappuoli R. From empiricism to rational design: a personal perspective of the evolution of vaccine development. Nat Rev Immunol 2014; 14:505-14. [PMID: 24925139 PMCID: PMC7096907 DOI: 10.1038/nri3694] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Vaccination, which is the most effective medical intervention that has ever been introduced, originated from the observation that individuals who survived a plague or smallpox would not get the disease twice. To mimic the protective effects of natural infection, Jenner - and later Pasteur - inoculated individuals with attenuated or killed disease-causing agents. This empirical approach inspired a century of vaccine development and the effective prophylaxis of many infectious diseases. From the 1980s, several waves of new technologies have enabled the development of novel vaccines that would not have been possible using the empirical approach. The technological revolution in the field of vaccination is now continuing, and it is delivering novel and safer vaccines. In this Timeline article, we provide our views on the transition from empiricism to rational vaccine design.
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Affiliation(s)
| | - Rino Rappuoli
- Novartis Vaccines, Via Fiorentina 1, Siena, 53100 Italy
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539
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Mac-Daniel L, Buckwalter MR, Berthet M, Virk Y, Yui K, Albert ML, Gueirard P, Ménard R. Local immune response to injection of Plasmodium sporozoites into the skin. THE JOURNAL OF IMMUNOLOGY 2014; 193:1246-57. [PMID: 24981449 DOI: 10.4049/jimmunol.1302669] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Malarial infection is initiated when the sporozoite form of the Plasmodium parasite is inoculated into the skin by a mosquito. Sporozoites invade hepatocytes in the liver and develop into the erythrocyte-infecting form of the parasite, the cause of clinical blood infection. Protection against parasite development in the liver can be induced by injection of live attenuated parasites that do not develop in the liver and thus do not cause blood infection. Radiation-attenuated sporozoites (RAS) and genetically attenuated parasites are now considered as lead candidates for vaccination of humans against malaria. Although the skin appears as the preferable administration route, most studies in rodents, which have served as model systems, have been performed after i.v. injection of attenuated sporozoites. In this study, we analyzed the early response to Plasmodium berghei RAS or wild-type sporozoites (WTS) injected intradermally into C57BL/6 mice. We show that RAS have a similar in vivo distribution to WTS and that both induce a similar inflammatory response consisting of a biphasic recruitment of polymorphonuclear neutrophils and inflammatory monocytes in the skin injection site and proximal draining lymph node (dLN). Both WTS and RAS associate with neutrophils and resident myeloid cells in the skin and the dLN, transform inside CD11b(+) cells, and induce a Th1 cytokine profile in the dLN. WTS and RAS are also similarly capable of priming parasite-specific CD8(+) T cells. These studies delineate the early and local response to sporozoite injection into the skin, and suggest that WTS and RAS prime the host immune system in a similar fashion.
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Affiliation(s)
- Laura Mac-Daniel
- Unité de Biologie et Génétique du Paludisme, Institut Pasteur, 75724 Paris Cedex 15, France
| | - Matthew R Buckwalter
- Unité d'Immunobiologie des Cellules Dendritiques, Institut Pasteur, 75724 Paris Cedex 15, France; and
| | - Michèle Berthet
- Unité de Biologie et Génétique du Paludisme, Institut Pasteur, 75724 Paris Cedex 15, France
| | - Yasemin Virk
- Unité d'Immunobiologie des Cellules Dendritiques, Institut Pasteur, 75724 Paris Cedex 15, France; and
| | - Katsuyuki Yui
- Division of Immunology, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Matthew L Albert
- Unité d'Immunobiologie des Cellules Dendritiques, Institut Pasteur, 75724 Paris Cedex 15, France; and
| | - Pascale Gueirard
- Unité de Biologie et Génétique du Paludisme, Institut Pasteur, 75724 Paris Cedex 15, France
| | - Robert Ménard
- Unité de Biologie et Génétique du Paludisme, Institut Pasteur, 75724 Paris Cedex 15, France;
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540
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Nahrendorf W, Scholzen A, Bijker EM, Teirlinck AC, Bastiaens GJH, Schats R, Hermsen CC, Visser LG, Langhorne J, Sauerwein RW. Memory B-cell and antibody responses induced by Plasmodium falciparum sporozoite immunization. J Infect Dis 2014; 210:1981-90. [PMID: 24970846 PMCID: PMC4241945 DOI: 10.1093/infdis/jiu354] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Background Immunization of healthy volunteers during receipt of chemoprophylaxis with Plasmodium falciparum sporozoites (CPS-immunization) induces sterile protection from malaria. Antibody responses have long been known to contribute to naturally acquired immunity against malaria, but their association with sterile protection after whole sporozoite immunization is not well established. We therefore studied the induction and kinetics of malaria parasite antigen-specific antibodies and memory B-cells (MBCs) during CPS-immunization and their correlation with protection from challenge infection. Methods We assessed humoral reactivity to 9 antigens representing different stages of the life cycle of P. falciparum by performing standardized MBC enzyme-linked immunospot and enzyme-linked immunosorbent assays on peripheral blood mononuclear cells and plasma samples from 38 Dutch volunteers enrolled in 2 randomized controlled clinical trials. Results MBCs and antibodies recognizing pre-erythrocytic and cross-stage antigens were gradually acquired during CPS-immunization. The magnitude of these humoral responses did not correlate with protection but directly reflected parasite exposure in CPS-immunization and challenge. Conclusions Humoral responses to the malarial antigens circumsporozoite protein, liver-stage antigen-1, apical membrane antigen-1, and merozoite surface protein-1 do not to predict protection from challenge infection but can be used as sensitive marker of recent parasite exposure. Clinical Trials Registration NCT01236612 and NCT01218893.
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Affiliation(s)
- Wiebke Nahrendorf
- Department of Medical Microbiology, Radboud university medical center, Nijmegen Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Anja Scholzen
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
| | - Else M Bijker
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
| | - Anne C Teirlinck
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
| | - Guido J H Bastiaens
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
| | - Remko Schats
- Department of Infectious Diseases, Leiden University Medical Center, The Netherlands
| | - Cornelus C Hermsen
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
| | - Leo G Visser
- Department of Infectious Diseases, Leiden University Medical Center, The Netherlands
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research, London, United Kingdom
| | - Robert W Sauerwein
- Department of Medical Microbiology, Radboud university medical center, Nijmegen
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541
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Peng X, Keitany GJ, Vignali M, Chen L, Gibson C, Choi K, Huang F, Wang R. Artesunate versus chloroquine infection-treatment-vaccination defines stage-specific immune responses associated with prolonged sterile protection against both pre-erythrocytic and erythrocytic Plasmodium yoelii infection. THE JOURNAL OF IMMUNOLOGY 2014; 193:1268-77. [PMID: 24958899 DOI: 10.4049/jimmunol.1400296] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sterile protection against malaria infection can be achieved through vaccination of mice and humans with whole Plasmodium spp. parasites. One such method, known as infection-treatment-vaccination (ITV), involves immunization with wild type sporozoites (spz) under drug coverage. In this work, we used the different effects of antimalarial drugs chloroquine (CQ) and artesunate (AS) on blood stage (BS) parasites to dissect the stage-specific immune responses in mice immunized with Plasmodium yoelii spz under either drug, as well as their ability to protect mice against challenge with spz or infected RBCs (iRBCs). Whereas CQ-ITV induced sterile protection against challenge with both spz and iRBCs, AS-ITV only induced sterile protection against spz challenge. Importantly, AS-ITV delayed the onset of BS infection, indicating that both regimens induced cross-stage immunity. Moreover, both CQ- and AS-ITV induced CD8(+) T cells in the liver that eliminated malaria-infected hepatocytes in vitro, as well as Abs that recognized pre-erythrocytic parasites. Sera from both groups of mice inhibited spz invasion of hepatocytes in vitro, but only CQ-ITV induced high levels of anti-BS Abs. Finally, passive transfer of sera from CQ-ITV-treated mice delayed the onset of erythrocytic infection in the majority of mice challenged with P. yoelii iRBCs. Besides constituting the first characterization, to our knowledge, of AS-ITV as a vaccination strategy, our data show that ITV strategies that lead to subtle differences in the persistence of parasites in the blood enable the characterization of the resulting immune responses, which will contribute to future research in vaccine design and malaria interventions.
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Affiliation(s)
- Xiaohong Peng
- Department of Pathogenic Biology, Third Military Medical University, Chongqing 400038, China; Seattle Biomedical Research Institute, Seattle, WA 98109; and
| | | | - Marissa Vignali
- Seattle Biomedical Research Institute, Seattle, WA 98109; and
| | - Lin Chen
- Department of Pathogenic Biology, Third Military Medical University, Chongqing 400038, China; Seattle Biomedical Research Institute, Seattle, WA 98109; and
| | - Claire Gibson
- Seattle Biomedical Research Institute, Seattle, WA 98109; and
| | - Kimberly Choi
- Seattle Biomedical Research Institute, Seattle, WA 98109; and
| | - Fusheng Huang
- Department of Pathogenic Biology, Third Military Medical University, Chongqing 400038, China
| | - Ruobing Wang
- Seattle Biomedical Research Institute, Seattle, WA 98109; and Department of Global Health, University of Washington, Seattle, WA 98125
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542
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Van Braeckel-Budimir N, Harty JT. CD8 T-cell-mediated protection against liver-stage malaria: lessons from a mouse model. Front Microbiol 2014; 5:272. [PMID: 24936199 PMCID: PMC4047659 DOI: 10.3389/fmicb.2014.00272] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/19/2014] [Indexed: 01/08/2023] Open
Abstract
Malaria is a major global health problem, with severe mortality in children living in sub-Saharan Africa, and there is currently no licensed, effective vaccine. However, vaccine-induced protection from Plasmodium infection, the causative agent of malaria, was established for humans in small clinical trials and for rodents in the 1960s. Soon after, a critical role for memory CD8 T cells in vaccine-induced protection against Plasmodium liver-stage infection was established in rodent models and is assumed to apply to humans. However, these seminal early studies have led to only modest advances over the ensuing years in our understanding the basic features of memory CD8 T cells required for protection against liver-stage Plasmodium infection, an issue which has likely impeded the development of effective vaccines for humans. Given the ethical and practical limitations in gaining mechanistic insight from human vaccine and challenge studies, animal models still have an important role in dissecting the basic parameters underlying memory CD8 T-cell immunity to Plasmodium. Here, we will highlight recent data from our own work in the mouse model of Plasmodium infection that identify quantitative and qualitative features of protective memory CD8 T-cell responses. Finally, these lessons will be discussed in the context of recent findings from clinical trials of vaccine-induced protection in controlled human challenge models.
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Affiliation(s)
| | - John T Harty
- Department of Microbiology, University of Iowa Iowa, IA, USA
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543
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Sargeant JM, Kelton DF, O'Connor AM. Randomized Controlled Trials and Challenge Trials: Design and Criterion for Validity. Zoonoses Public Health 2014; 61 Suppl 1:18-27. [DOI: 10.1111/zph.12126] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Indexed: 11/29/2022]
Affiliation(s)
- J. M. Sargeant
- Centre for Public Health and Zoonoses; University of Guelph; Guelph ON Canada
- Department of Population Medicine; Ontario Veterinary College; University of Guelph; Guelph ON Canada
| | - D. F. Kelton
- Centre for Public Health and Zoonoses; University of Guelph; Guelph ON Canada
- Department of Population Medicine; Ontario Veterinary College; University of Guelph; Guelph ON Canada
| | - A. M. O'Connor
- Department of Veterinary Diagnostic and Production Animal Medicine; Iowa State University College of Veterinary Medicine; Ames IA USA
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544
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Stoler J, Al Dashti R, Anto F, Fobil JN, Awandare GA. Deconstructing "malaria": West Africa as the next front for dengue fever surveillance and control. Acta Trop 2014; 134:58-65. [PMID: 24613157 DOI: 10.1016/j.actatropica.2014.02.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 02/19/2014] [Accepted: 02/23/2014] [Indexed: 11/15/2022]
Abstract
Presumptive treatment of febrile illness patients for malaria remains the norm in endemic areas of West Africa, and "malaria" remains the top source of health facility outpatient visits in many West African nations. Many other febrile illnesses, including bacterial, viral, and fungal infections, share a similar symptomatology as malaria and are routinely misdiagnosed as such; yet growing evidence suggests that much of the burden of febrile illness is often not attributable to malaria. Dengue fever is one of several viral diseases with symptoms similar to malaria, and the combination of rapid globalization, the long-standing presence of Aedes mosquitoes, case reports from travelers, and recent seroprevalence surveys all implicate West Africa as an emerging front for dengue surveillance and control. This paper integrates recent vector ecology, public health, and clinical medicine literature about dengue in West Africa across community, regional, and global geographic scales. We present a holistic argument for greater attention to dengue fever surveillance in West Africa and renew the call for improving differential diagnosis of febrile illness patients in the region.
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Affiliation(s)
- Justin Stoler
- Department of Geography and Regional Studies, University of Miami, 1300 Campo Sano Avenue, Coral Gables, FL, USA; Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL, USA.
| | - Rawan Al Dashti
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL, USA.
| | - Francis Anto
- Department of Epidemiology and Disease Control, University of Ghana, Legon, Ghana.
| | - Julius N Fobil
- Department of Biological, Environmental & Occupational Health Sciences, University of Ghana, Legon, Ghana.
| | - Gordon A Awandare
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Ghana.
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545
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de Souza JB. Protective immunity against malaria after vaccination. Parasite Immunol 2014; 36:131-9. [PMID: 24188045 DOI: 10.1111/pim.12086] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 10/29/2013] [Indexed: 11/28/2022]
Abstract
A good understanding of the immunological correlates of protective immunity is an important requirement for the development of effective vaccines against malaria. However, this concern has received little attention even in the face of two decades of intensive vaccine research. Here, we review the immune response to blood-stage malaria, with a particular focus on the type of vaccine most likely to induce the kind of response required to give strong protection against infection.
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Affiliation(s)
- J B de Souza
- Faculty of Infectious and Tropical Diseases, Department of Immunity and Infection, London School of Hygiene & Tropical Medicine, London, UK; Division of Infection & Immunity, University College London Medical School, London, UK
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546
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Bijker EM, Teirlinck AC, Schats R, van Gemert GJ, van de Vegte-Bolmer M, van Lieshout L, IntHout J, Hermsen CC, Scholzen A, Visser LG, Sauerwein RW. Cytotoxic markers associate with protection against malaria in human volunteers immunized with Plasmodium falciparum sporozoites. J Infect Dis 2014; 210:1605-15. [PMID: 24872326 PMCID: PMC4208622 DOI: 10.1093/infdis/jiu293] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Immunization of healthy volunteers by bites from Plasmodium falciparum-infected mosquitoes during chloroquine chemoprophylaxis (hereafter, chemoprophylaxis and sporozoites [CPS] immunization) induces sterile protection against malaria. CPS-induced protection is mediated by immunity against pre-erythrocytic stages, presumably at least partially by cytotoxic cellular responses. We therefore aimed to investigate the association of CPS-induced cytotoxic T-cell markers with protection. METHODS In a double-blind randomized controlled trial, we performed dose titration of CPS immunization followed by homologous challenge infection in 29 subjects. Immune responses were assessed by in vitro restimulation of peripheral blood mononuclear cells and flow cytometry. RESULTS Dose-dependent complete protection was obtained in 4 of 5 volunteers after immunization with bites from 45 P. falciparum-infected mosquitoes, in 8 of 9 volunteers with bites from 30, and in 5 of 10 volunteers with bites from 15 (odds ratio [OR], 5.0; 95% confidence interval [CI], 1.5-17). Completely protected subjects had significantly higher proportions of CD4 T cells expressing the degranulation marker CD107a (OR, 8.4; 95% CI, 1.5-123; P = .011) and CD8 cells producing granzyme B (OR, 11; 95% CI, 1.9-212; P = .004) after P. falciparum restimulation. CONCLUSIONS These data underline the efficiency of CPS immunization to induce sterile protection and support a possible role for cytotoxic CD4 and CD8 T-cell responses in pre-erythrocytic immunity. CLINICAL TRIALS REGISTRATION NCT01218893.
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Affiliation(s)
| | | | | | | | | | - Lisette van Lieshout
- Department of Medical Microbiology, Department of Parasitology, Leiden University Medical Center, The Netherlands
| | - Joanna IntHout
- Department for Health Evidence, Section Biostatistics, Radboud university medical center, Nijmegen
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547
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Gannavaram S, Dey R, Avishek K, Selvapandiyan A, Salotra P, Nakhasi HL. Biomarkers of safety and immune protection for genetically modified live attenuated leishmania vaccines against visceral leishmaniasis - discovery and implications. Front Immunol 2014; 5:241. [PMID: 24904589 PMCID: PMC4033241 DOI: 10.3389/fimmu.2014.00241] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/09/2014] [Indexed: 12/16/2022] Open
Abstract
Despite intense efforts there is no safe and efficacious vaccine against visceral leishmaniasis, which is fatal and endemic in many tropical countries. A major shortcoming in the vaccine development against blood-borne parasitic agents such as Leishmania is the inadequate predictive power of the early immune responses mounted in the host against the experimental vaccines. Often immune correlates derived from in-bred animal models do not yield immune markers of protection that can be readily extrapolated to humans. The limited efficacy of vaccines based on DNA, subunit, heat killed parasites has led to the realization that acquisition of durable immunity against the protozoan parasites requires a controlled infection with a live attenuated organism. Recent success of irradiated malaria parasites as a vaccine candidate further strengthens this approach to vaccination. We developed several gene deletion mutants in Leishmania donovani as potential live attenuated vaccines and reported extensively on the immunogenicity of LdCentrin1 deleted mutant in mice, hamsters, and dogs. Additional limited studies using genetically modified live attenuated Leishmania parasites as vaccine candidates have been reported. However, for the live attenuated parasite vaccines, the primary barrier against widespread use remains the absence of clear biomarkers associated with protection and safety. Recent studies in evaluation of vaccines, e.g., influenza and yellow fever vaccines, using systems biology tools demonstrated the power of such strategies in understanding the immunological mechanisms that underpin a protective phenotype. Applying similar tools in isolated human tissues such as PBMCs from healthy individuals infected with live attenuated parasites such as LdCen(-/-) in vitro followed by human microarray hybridization experiments will enable us to understand how early vaccine-induced gene expression profiles and the associated immune responses are coordinately regulated in normal individuals. In addition, comparative analysis of biomarkers in PBMCs from asymptomatic or healed visceral leishmaniasis individuals in response to vaccine candidates including live attenuated parasites may provide clues about determinants of protective immunity and be helpful in shaping the final Leishmania vaccine formulation in the clinical trials.
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Affiliation(s)
- Sreenivas Gannavaram
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration , Bethesda, MD , USA
| | - Ranadhir Dey
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration , Bethesda, MD , USA
| | - Kumar Avishek
- National Institute of Pathology, Indian Council of Medical Research , New Delhi , India
| | | | - Poonam Salotra
- National Institute of Pathology, Indian Council of Medical Research , New Delhi , India
| | - Hira L Nakhasi
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration , Bethesda, MD , USA
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548
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Clambey ET, Davenport B, Kappler JW, Marrack P, Homann D. Molecules in medicine mini review: the αβ T cell receptor. J Mol Med (Berl) 2014; 92:735-41. [PMID: 24848996 DOI: 10.1007/s00109-014-1145-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/17/2014] [Accepted: 01/21/2014] [Indexed: 01/01/2023]
Abstract
As an integral part of the mammalian immune system, a distributed network of tissues, cells, and extracellular factors, T lymphocytes perform and control a multitude of activities that collectively contribute to the effective establishment, maintenance, and restoration of tissue and organismal integrity. Development and function of T cells is controlled by the T cell receptor (TCR), a heterodimeric cell surface protein uniquely expressed on T cells. During T cell development, the TCR undergoes extensive somatic diversification that generates a diverse T cell repertoire capable of recognizing an extraordinary range of protein and nonprotein antigens presented in the context of major histocompatibility complex molecules (MHC). In this review, we provide an introduction to the TCR, describing underlying principles that position this molecule as a central regulator of the adaptive immune system involved in responses ranging from tissue protection and preservation to pathology and autoimmunity.
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Affiliation(s)
- Eric T Clambey
- Department of Anesthesiology, Mucosal Inflammation Program, University of Colorado School of Medicine, Mail Stop B112, Research Complex 2, 12700 East 19th Avenue, Aurora, CO, 80045, USA,
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549
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Hleb EYL, Lapotko DO. Malaria theranostics using hemozoin-generated vapor nanobubbles. Theranostics 2014; 4:761-9. [PMID: 24883125 PMCID: PMC4038757 DOI: 10.7150/thno.9128] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 04/26/2014] [Indexed: 12/31/2022] Open
Abstract
Malaria remains a widespread and deadly infectious human disease, with increasing diagnostic and therapeutic challenges due to the drug resistance and aggressiveness of malaria infection. Early detection and innovative approaches for parasite destruction are needed. The high optical absorbance and nano-size of hemozoin crystals have been exploited to detect and mechanically destroy the malaria parasite in a single theranostic procedure. Transient vapor nanobubbles are generated around hemozoin crystals in malaria parasites in infected erythrocytes in response to a single short laser pulse. Optical scattering signals of the nanobubble report the presence of the malaria parasite. The mechanical impact of the same nanobubble physically destroys the parasite in nanoseconds in a drug-free manner. Laser-induced nanobubble treatment of human blood in vitro results in destruction of up to 95% of parasites after a single procedure, and delivers an 8-fold better parasiticidal efficacy compared to standard chloroquine drug treatment. The mechanism of destruction is highly selective for malaria infected red cells and does not harm neighboring, uninfected erythrocytes. Thus, laser pulse-induced vapor nanobubble generation around hemozoin supports both rapid and highly specific detection and destruction of malaria parasites in one theranostic procedure.
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Affiliation(s)
| | - Dmitri O. Lapotko
- 1. Department of Biochemistry and Cell Biology, Rice University, Houston, TX
- 2. Department of Physics and Astronomy, Rice University, Houston, TX
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550
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Lau LS, Fernandez-Ruiz D, Mollard V, Sturm A, Neller MA, Cozijnsen A, Gregory JL, Davey GM, Jones CM, Lin YH, Haque A, Engwerda CR, Nie CQ, Hansen DS, Murphy KM, Papenfuss AT, Miles JJ, Burrows SR, de Koning-Ward T, McFadden GI, Carbone FR, Crabb BS, Heath WR. CD8+ T cells from a novel T cell receptor transgenic mouse induce liver-stage immunity that can be boosted by blood-stage infection in rodent malaria. PLoS Pathog 2014; 10:e1004135. [PMID: 24854165 PMCID: PMC4031232 DOI: 10.1371/journal.ppat.1004135] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 04/06/2014] [Indexed: 12/15/2022] Open
Abstract
To follow the fate of CD8+ T cells responsive to Plasmodium berghei ANKA (PbA) infection, we generated an MHC I-restricted TCR transgenic mouse line against this pathogen. T cells from this line, termed PbT-I T cells, were able to respond to blood-stage infection by PbA and two other rodent malaria species, P. yoelii XNL and P. chabaudi AS. These PbT-I T cells were also able to respond to sporozoites and to protect mice from liver-stage infection. Examination of the requirements for priming after intravenous administration of irradiated sporozoites, an effective vaccination approach, showed that the spleen rather than the liver was the main site of priming and that responses depended on CD8α+ dendritic cells. Importantly, sequential exposure to irradiated sporozoites followed two days later by blood-stage infection led to augmented PbT-I T cell expansion. These findings indicate that PbT-I T cells are a highly versatile tool for studying multiple stages and species of rodent malaria and suggest that cross-stage reactive CD8+ T cells may be utilized in liver-stage vaccine design to enable boosting by blood-stage infections. Malaria is a disease caused by Plasmodium species, which have a highly complex life cycle involving both liver and blood stages of mammalian infection. To prevent disease, one strategy has been to induce CD8+ T cells against liver-stage parasites, usually by immunization with stage-specific antigens. Here we describe a T cell receptor specificity that recognizes an antigen expressed in both the liver and blood stages of several rodent Plasmodium species. We generated a T cell receptor transgenic mouse with this specificity and showed that T cells from this line could protect against liver-stage infection. We used this novel tool to identify the site and cell-type involved in priming to a recently developed intravenous attenuated sporozoite vaccine shown to have efficacy in humans. We showed that CD8+ T cells with this specificity could protect against liver-stage infection while causing pathology to the blood stage. Finally, we provided evidence that T cells with cross-stage specificity can be primed and boosted on alternative stages, raising the possibility that antigens expressed in multiple stages might be ideal vaccine candidates for generating strong immunity to liver-stage parasites.
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Affiliation(s)
- Lei Shong Lau
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Daniel Fernandez-Ruiz
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Vanessa Mollard
- The School of Botany, University of Melbourne, Parkville, Victoria, Australia
| | - Angelika Sturm
- The School of Botany, University of Melbourne, Parkville, Victoria, Australia
| | - Michelle A. Neller
- The QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Anton Cozijnsen
- The School of Botany, University of Melbourne, Parkville, Victoria, Australia
| | - Julia L. Gregory
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Gayle M. Davey
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Claerwen M. Jones
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Yi-Hsuan Lin
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Ashraful Haque
- The QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | | | - Catherine Q. Nie
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Macfarlane Burnet Institute for Medical Research & Public Health, Melbourne, Victoria, Australia
| | - Diana S. Hansen
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Kenneth M. Murphy
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Anthony T. Papenfuss
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - John J. Miles
- The QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, Wales, United Kingdom
| | - Scott R. Burrows
- The QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | | | | | - Francis R. Carbone
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Brendan S. Crabb
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
- Macfarlane Burnet Institute for Medical Research & Public Health, Melbourne, Victoria, Australia
- Monash University, Clayton, Victoria, Australia
- * E-mail: (BSC); (WRH)
| | - William R. Heath
- Department of Microbiology and Immunology, The Peter Doherty Institute, University of Melbourne, Parkville, Victoria, Australia
- The ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
- * E-mail: (BSC); (WRH)
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