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Nouatin O, Ibáñez J, Fendel R, Ngoa UA, Lorenz FR, Dejon-Agobé JC, Edoa JR, Flügge J, Brückner S, Esen M, Theisen M, Hoffman SL, Moutairou K, Luty AJF, Lell B, Kremsner PG, Adegnika AA, Mordmüller B. Cellular and antibody response in GMZ2-vaccinated Gabonese volunteers in a controlled human malaria infection trial. Malar J 2022; 21:191. [PMID: 35715803 PMCID: PMC9204906 DOI: 10.1186/s12936-022-04169-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 04/23/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Antibody and cellular memory responses following vaccination are important measures of immunogenicity. These immune markers were quantified in the framework of a vaccine trial investigating the malaria vaccine candidate GMZ2. METHODS Fifty Gabonese adults were vaccinated with two formulations (aluminum Alhydrogel and CAF01) of GMZ2 or a control vaccine (Verorab). Vaccine efficacy was assessed using controlled human malaria infection (CHMI) by direct venous inoculation of 3200 live Plasmodium falciparum sporozoites (PfSPZ Challenge). GMZ2-stimulated T and specific B-cell responses were estimated by flow cytometry before and after vaccination. Additionally, the antibody response against 212 P. falciparum antigens was estimated before CHMI by protein microarray. RESULTS Frequencies of pro- and anti-inflammatory CD4+ T cells stimulated with the vaccine antigen GMZ2 as well as B cell profiles did not change after vaccination. IL-10-producing CD4+ T cells and CD20+ IgG+ B cells were increased post-vaccination regardless of the intervention, thus could not be specifically attributed to any malaria vaccine regimen. In contrast, GMZ2-specific antibody response increased after the vaccination, but was not correlated to protection. Antibody responses to several P. falciparum blood and liver stage antigens (MSP1, MSP4, MSP8, PfEMP1, STARP) as well as the breadth of the malaria-specific antibody response were significantly higher in protected study participants. CONCLUSIONS In lifelong malaria exposed adults, the main marker of protection against CHMI is a broad antibody pattern recognizing multiple stages of the plasmodial life cycle. Despite vaccination with GMZ2 using a novel formulation, expansion of the GMZ2-stimulated T cells or the GMZ2-specific B cell response was limited, and the vaccine response could not be identified as a marker of protection against malaria. Trial registration PACTR; PACTR201503001038304; Registered 17 February 2015; https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=1038.
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Affiliation(s)
- Odilon Nouatin
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon. .,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany. .,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany. .,Département de Biochimie Et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Bénin.
| | - Javier Ibáñez
- Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany
| | - Rolf Fendel
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon. .,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany. .,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany.
| | - Ulysse A Ngoa
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon
| | - Freia-Raphaella Lorenz
- Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany
| | - Jean-Claude Dejon-Agobé
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Jean Ronald Edoa
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany
| | - Judith Flügge
- Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany
| | - Sina Brückner
- Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany
| | - Meral Esen
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany.,Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tübingen, Germany
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark.,Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark
| | | | - Kabirou Moutairou
- Département de Biochimie Et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d'Abomey-Calavi, Cotonou, Bénin
| | - Adrian J F Luty
- Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et a l'Enfance, Calavi, Bénin.,MERIT, Université de Paris, Paris, IRD, France
| | - Bertrand Lell
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Peter G Kremsner
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany
| | - Ayola A Adegnika
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany.,Department of Parasitology, Leiden University Medical Centre (LUMC), 2333 ZA, Leiden, The Netherlands.,Fondation pour la Recherche Scientifique, 72 BP45, Cotonou, Bénin
| | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné, BP : 242, Lambaréné, Gabon.,Institute of Tropical Medicine, University Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.,German Centre for Infection Research (DZIF), Partner Site, Tübingen, Germany.,Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
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2
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Lu X, Zhang J, Li YQ, Liu QX, Zhou D, Deng XF, Qiu Y, Chen Q, Li MY, Liu XQ, Dai JG, Zheng H. Plasmodium Circumsporozoite Protein Enhances the Efficacy of Gefitinib in Lung Adenocarcinoma Cells by Inhibiting Autophagy via Proteasomal Degradation of LC3B. Front Cell Dev Biol 2022; 10:830046. [PMID: 35186935 PMCID: PMC8851824 DOI: 10.3389/fcell.2022.830046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 01/13/2022] [Indexed: 12/24/2022] Open
Abstract
Background: Almost all lung adenocarcinoma (LUAD) patients with EGFR mutant will develop resistance to EGFR-TKIs, which limit the long-term clinical application of these agents. Accumulating evidence shows one of the main reasons for resistance to EGFR-TKIs is induction of autophagy in tumor cells. Our previous study found that circumsporozoite protein (CSP) in Plasmodium can suppress autophagy in host hepatocytes. However, it is unknown whether CSP-mediated inhibition of autophagy could improve the anti-tumor effect of EGFR-TKIs. Methods: We constructed A549 and H1975 cell lines with stable overexpression of CSP (OE-CSP cells). CCK-8, Lactate Dehydrogenase (LDH), flow cytometry, and colony analysis were performed to observe the effect of CSP overexpression on cell viability, apoptosis rate, and colony formation ratio. The sensitizing effect of CSP on gefitinib was evaluated in vivo using a subcutaneous tumor model in nude mice and immunohistochemical assay. The role of CSP in regulation of autophagy was investigated by laser confocal microscopy assay and western blotting. A transcriptome sequencing assay and real-time polymerase chain reaction were used to determine the levels of mRNA for autophagy-related proteins. Cycloheximide (CHX), MG132, TAK-243, and immunoprecipitation assays were used to detect and confirm proteasomal degradation of LC3B. Results: OE-CSP A549 and H1975 cells were more sensitive to gefitinib, demonstrating significant amounts of apoptosis and decreased viability. In the OE-CSP group, autophagy was significantly inhibited, and there was a decrease in LC3B protein after exposure to gefitinib. Cell viability and colony formed ability were recovered when OE-CSP cells were exposed to rapamycin. In nude mice with xenografts of LUAD cells, inhibition of autophagy by CSP resulted in suppression of cell growth, and more marked apoptosis during exposure to gefitinib. CSP promoted ubiquitin-proteasome degradation of LC3B, leading to inhibition of autophagy in LUAD cells after treatment with gefitinib. When LUAD cells were treated with ubiquitin activating enzyme inhibitor TAK-243, cell viability, apoptosis, and growth were comparable between the OE-CSP group and a control group both in vivo and in vitro. Conclusion: CSP can inhibit gefitinib-induced autophagy via proteasomal degradation of LC3B, which suggests that CSP could be used as an autophagy inhibitor to sensitize EGFR-TKIs.
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Affiliation(s)
- Xiao Lu
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Jiao Zhang
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Yan-Qi Li
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Quan-Xing Liu
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Dong Zhou
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xu-Feng Deng
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Yuan Qiu
- Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Qian Chen
- Cancer Center of Daping Hospital, Army Medical University, Chongqing, China
| | - Man-Yuan Li
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xiao-Qing Liu
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Ji-Gang Dai
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
- *Correspondence: Hong Zheng, ; Ji-Gang Dai,
| | - Hong Zheng
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
- *Correspondence: Hong Zheng, ; Ji-Gang Dai,
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3
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Reeder SM, Bah MA, Tursi NJ, Brooks RC, Patel A, Esquivel R, Eaton A, Jhun H, Chu J, Kim K, Xu Z, Zavala F, Weiner DB. Strategic Variants of CSP Delivered as SynDNA Vaccines Demonstrate Heterogeneity of Immunogenicity and Protection from Plasmodium Infection in a Murine Model. Infect Immun 2021; 89:e0072820. [PMID: 34152830 PMCID: PMC8445182 DOI: 10.1128/iai.00728-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 05/27/2021] [Indexed: 11/20/2022] Open
Abstract
Malaria infects millions of people every year, and despite recent advances in controlling disease spread, such as vaccination, it remains a global health concern. The circumsporozoite protein (CSP) has long been acknowledged as a key target in antimalarial immunity. Leveraging the DNA vaccine platform against this formidable pathogen, the following five synthetic DNA vaccines encoding variations of CSP were designed and studied: 3D7, GPI1, ΔGPI, TM, and DD2. Among the single CSP antigen constructs, a range of immunogenicity was observed with ΔGPI generating the most robust immunity. In an intravenous (i.v.) sporozoite challenge, the best protection among vaccinated mice was achieved by ΔGPI, which performed almost as well as the monoclonal antibody 311 (MAb 311) antibody control. Further analyses revealed that ΔGPI develops high-molecular-weight multimers in addition to monomeric CSP. We then compared the immunity generated by ΔGPI versus synDNA mimics for the antimalaria vaccines RTS,S and R21. The anti-CSP antibody responses induced were similar among these three immunogens. T cell responses demonstrated that ΔGPI induced a more focused anti-CSP response. In an infectious mosquito challenge, all three of these constructs generated inhibition of liver-stage infection as well as immunity from blood-stage parasitemia. This study demonstrates that synDNA mimics of complex malaria immunogens can provide substantial protection as can a novel synDNA vaccine ΔGPI.
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Affiliation(s)
- Sophia M. Reeder
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Mamadou A. Bah
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Nicholas J. Tursi
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Rebekah C. Brooks
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Ami Patel
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Rianne Esquivel
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Alison Eaton
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Hugo Jhun
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Jacqueline Chu
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Kevin Kim
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Ziyang Xu
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - David B. Weiner
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
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4
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Budroni S, Buricchi F, Cavallone A, Bourguignon P, Caubet M, Dewar V, D'Oro U, Finco O, Garçon N, El Idrissi M, Janssens M, Leroux-Roels G, Marchant A, Schwarz T, Van Damme P, Volpini G, van der Most R, Didierlaurent AM, Burny W. Antibody avidity, persistence, and response to antigen recall: comparison of vaccine adjuvants. NPJ Vaccines 2021; 6:78. [PMID: 34021167 PMCID: PMC8140094 DOI: 10.1038/s41541-021-00337-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 04/09/2021] [Indexed: 12/12/2022] Open
Abstract
Differences in innate immune ‘imprinting’ between vaccine adjuvants may mediate dissimilar effects on the quantity/quality of persisting adaptive responses. We compared antibody avidity maturation, antibody/memory B cell/CD4+ T cell response durability, and recall responses to non-adjuvanted fractional-dose antigen administered 1-year post-immunization (Day [D]360), between hepatitis B vaccines containing Adjuvant System (AS)01B, AS01E, AS03, AS04, or Alum (NCT00805389). Both the antibody and B cell levels ranked similarly (AS01B/E/AS03 > AS04 > Alum) at peak response, at D360, and following their increases post-antigen recall (D390). Proportions of high-avidity antibodies increased post-dose 2 across all groups and persisted at D360, but avidity maturation appeared to be more strongly promoted by AS vs. Alum. Post-antigen recall, frequencies of subjects with high-avidity antibodies increased only markedly in the AS groups. Among the AS, total antibody responses were lowest for AS04. However, proportions of high-avidity antibodies were similar between groups, suggesting that MPL in AS04 contributes to avidity maturation. Specific combinations of immunoenhancers in the AS, regardless of their individual nature, increase antibody persistence and avidity maturation.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Arnaud Marchant
- Institute for Medical Immunology, Université libre de Bruxelles, Brussels, Belgium
| | - Tino Schwarz
- Institute of Laboratory Medicine and Vaccination Center, Klinikum Wuerzburg Mitte, Standort Juliusspital, Academic Teaching Hospital of the University of Wuerzburg, Wuerzburg, Germany
| | - Pierre Van Damme
- Center for the Evaluation of Vaccination, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
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5
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Abstract
Introduction: An effective vaccine against malaria forms a global health priority. Both naturally acquired immunity and sterile protection induced by irradiated sporozoite immunization were described decades ago. Still no vaccine exists that sufficiently protects children in endemic areas. Identifying immunological correlates of vaccine efficacy can inform rational vaccine design and potentially accelerate clinical development.Areas covered: We discuss recent research on immunological correlates of malaria vaccine efficacy, including: insights from state-of-the-art omics platforms and systems vaccinology analyses; functional anti-parasitic assays; pre-immunization predictors of vaccine efficacy; and comparison of correlates of vaccine efficacy against controlled human malaria infections (CHMI) and against naturally acquired infections.Expert Opinion: Effective vaccination may be achievable without necessarily understanding immunological correlates, but the relatively disappointing efficacy of malaria vaccine candidates in target populations is concerning. Hypothesis-generating omics and systems vaccinology analyses, alongside assessment of pre-immunization correlates, have the potential to bring about paradigm-shifts in malaria vaccinology. Functional assays may represent in vivo effector mechanisms, but have scarcely been formally assessed as correlates. Crucially, evidence is still meager that correlates of vaccine efficacy against CHMI correspond with those against naturally acquired infections in target populations. Finally, the diversity of immunological assays and efficacy endpoints across malaria vaccine trials remains a major confounder.
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Affiliation(s)
| | - Matthew B B McCall
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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6
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Molina-Franky J, Cuy-Chaparro L, Camargo A, Reyes C, Gómez M, Salamanca DR, Patarroyo MA, Patarroyo ME. Plasmodium falciparum pre-erythrocytic stage vaccine development. Malar J 2020; 19:56. [PMID: 32013956 PMCID: PMC6998842 DOI: 10.1186/s12936-020-3141-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/25/2020] [Indexed: 12/13/2022] Open
Abstract
Worldwide strategies between 2010 and 2017 aimed at controlling malarial parasites (mainly Plasmodium falciparum) led to a reduction of just 18% regarding disease incidence rates. Many biologically-derived anti-malarial vaccine candidates have been developed to date; this has involved using many experimental animals, an immense amount of work and the investment of millions of dollars. This review provides an overview of the current state and the main results of clinical trials for sporozoite-targeting vaccines (i.e. the parasite stage infecting the liver) carried out by research groups in areas having variable malaria transmission rates. However, none has led to promising results regarding the effective control of the disease, thereby making it necessary to complement such efforts at finding/introducing new vaccine candidates by adopting a multi-epitope, multi-stage approach, based on minimal subunits of the main sporozoite proteins involved in the invasion of the liver.
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Affiliation(s)
- Jessica Molina-Franky
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Laura Cuy-Chaparro
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Anny Camargo
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - César Reyes
- PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia.,Animal Science Faculty, Universidad de Ciencias Aplicadas y Ambientales (U.D.C.A), Bogotá, Colombia.,3D Structures Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Marcela Gómez
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - David Ricardo Salamanca
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia.,Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Program in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Manuel Alfonso Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia. .,Basic Sciences Department, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia.
| | - Manuel Elkin Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia. .,Medical School, Universidad Nacional de Colombia, Bogotá, Colombia.
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7
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Kumar R, Loughland JR, Ng SS, Boyle MJ, Engwerda CR. The regulation of CD4
+
T cells during malaria. Immunol Rev 2019; 293:70-87. [DOI: 10.1111/imr.12804] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Rajiv Kumar
- Centre of Experimental Medicine and Surgery Institute of Medical Sciences Banaras Hindu University Varanasi UP India
- Department of Medicine Institute of Medical Sciences Banaras Hindu University Varanasi UP India
| | - Jessica R. Loughland
- Human Malaria Immunology Laboratory QIMR Berghofer Medical Research Institute Brisbane Australia
| | - Susanna S. Ng
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Brisbane Australia
| | - Michelle J. Boyle
- Human Malaria Immunology Laboratory QIMR Berghofer Medical Research Institute Brisbane Australia
| | - Christian R. Engwerda
- Immunology and Infection Laboratory QIMR Berghofer Medical Research Institute Brisbane Australia
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8
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Abstract
Immunotherapy has emerged as an effective strategy for the prevention and treatment of a variety of diseases, including cancer, infectious diseases, inflammatory diseases, and autoimmune diseases. Immunomodulatory nanosystems can readily improve the therapeutic effects and simultaneously overcome many obstacles facing the treatment method, such as inadequate immune stimulation, off-target side effects, and bioactivity loss of immune agents during circulation. In recent years, researchers have continuously developed nanomaterials with new structures, properties, and functions. This Review provides the most recent advances of nanotechnology for immunostimulation and immunosuppression. In cancer immunotherapy, nanosystems play an essential role in immune cell activation and tumor microenvironment modulation, as well as combination with other antitumor approaches. In infectious diseases, many encouraging outcomes from using nanomaterial vaccines against viral and bacterial infections have been reported. In addition, nanoparticles also potentiate the effects of immunosuppressive immune cells for the treatment of inflammatory and autoimmune diseases. Finally, the challenges and prospects of applying nanotechnology to modulate immunotherapy are discussed.
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Affiliation(s)
- Xiangru Feng
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
- University of Science and Technology of ChinaHefei230026P. R. China
| | - Weiguo Xu
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Zhongmin Li
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
- Department of Gastrointestinal Colorectal and Anal SurgeryChina–Japan Union Hospital of Jilin UniversityChangchun130033P. R. China
| | - Wantong Song
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Jianxun Ding
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
| | - Xuesi Chen
- Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022P. R. China
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9
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Beeson JG, Kurtovic L, Dobaño C, Opi DH, Chan JA, Feng G, Good MF, Reiling L, Boyle MJ. Challenges and strategies for developing efficacious and long-lasting malaria vaccines. Sci Transl Med 2019; 11:11/474/eaau1458. [DOI: 10.1126/scitranslmed.aau1458] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 08/05/2018] [Accepted: 11/02/2018] [Indexed: 12/24/2022]
Abstract
Although there has been major recent progress in malaria vaccine development, substantial challenges remain for achieving highly efficacious and durable vaccines against Plasmodium falciparum and Plasmodium vivax malaria. Greater knowledge of mechanisms and key targets of immunity are needed to accomplish this goal, together with new strategies for generating potent, long-lasting, functional immunity against multiple antigens. Implementation considerations in endemic areas will ultimately affect vaccine effectiveness, so innovations to simplify and enhance delivery are also needed. Whereas challenges remain, recent exciting progress and emerging knowledge promise hope for the future of malaria vaccines.
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10
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Abstract
The availability of an effective and appropriately implemented malaria vaccine would form a crucial cornerstone of public health efforts to fight this disease. Despite many decades of research, however, no malaria vaccine has yet shown satisfactory protective efficacy or been rolled-out. Validated immunological substitute endpoints have the potential to accelerate clinical vaccine development by reducing the required complexity, size, duration and cost of clinical trials. Besides facilitating clinical development of existing vaccine candidates, understanding immunological mechanisms of protection may drive the development of fundamentally new vaccination approaches. In this review we focus on correlates of protection in malaria vaccine development: Does immunogenicity predict malaria vaccine efficacy and why is this question particularly difficult? Have immunological correlates accelerated malaria vaccine development in the past and will they facilitate it in the future? Does Controlled Human Malaria Infection represent a valid model for identifying such immunological correlates, or a correlate of protection against naturally-acquired malaria in itself?
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Affiliation(s)
- Matthew B B McCall
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.
| | - Peter G Kremsner
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institut für Tropenmedizin, Universität Tübingen and Deutsches Zentrum für Infektionsforschung, Germany; Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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11
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Abstract
Le vaccin antipaludique RTS,S/AS01 a reçu un avis scientifique favorable de l’Agence Européenne des Médicaments (EMA) en Juillet 2015. L’Organisation Mondiale de la Santé (OMS) a recommandé l’introduction pilote de ce vaccin chez des enfants âgés d’au moins 5 mois en utilisant un schéma de vaccination comprenant 3 doses initiales espacées d’au moins un mois et une 4ème dose administrée 15 à 18 mois après la 3ème dose. Des essais cliniques et des modèles mathématiques ont montré que la protection partielle contre le paludisme conférée par le vaccin RTS,S/AS01 pourrait avoir un impact substantiel sur la santé publique si le vaccin est utilisé en association avec d’autres mesures de lutte antipaludique, en particulier dans les zones hautement endémiques. L’impact le plus important a été observé chez les enfants âgés de 5 mois ou plus ayant reçu 4 doses de RTS,S/AS01. Le vaccin sera ensuite évalué en situation réelle afin de déterminer son impact sur la mortalité, son innocuité dans le cadre d’une vaccination de routine, et la faisabilité opérationnelle d’administrer 4 doses du vaccin dont certaines nécessitant de nouveaux contacts dans le calendrier de vaccination. En cas de succès, cela permettra une mise en œuvre à plus grande échelle.
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12
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Dechkajorn W, Benjathummarak S, Kumsiri R, Maneerat Y. The role of the BAFF/APRIL system in the T cell-independent specific response to blood stage Plasmodium falciparum hemozoin. Cytokine 2018; 111:445-53. [PMID: 29884307 DOI: 10.1016/j.cyto.2018.05.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/28/2018] [Accepted: 05/29/2018] [Indexed: 01/18/2023]
Abstract
BACKGROUND The B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are tumor necrosis factor family members that regulate B cell maturation, proliferation, survival and function. We have previously shown that blood-stage Plasmodium falciparum hemozoin (HZ) can act as a T-independent antigen (TI Ag) that induces the production of specific IgG to soluble crude P. falciparum Ag through the BAFF pathway. However, we have not yet clarified whether HZ need APRIL signaling in the TI response. Here, we aimed to clarify whether both BAFF and APRIL signaling pathways play roles in HZ induction of specific antibody production without T-cell help. METHODS Normal monocytes alone or co-cultured with naïve B cells were stimulated by HZ (10 µM) in vitro. Naïve B cell cultures, with HZ alone or with exogenous recombinant BAFF (rBAFF) and recombinant APRIL (rAPRIL) plus recombinant IL-4 (rIL-4) for 6 and 10 days were used as controls to investigate activation of B cells. At various times, the levels of sBAFF, sAPRIL, and HZ-specific IgG in the culture supernatants were assessed by enzyme-linked immunosorbent assay. The BAFF and APRIL expression levels on the HZ-stimulated monocytes and their specific receptors on activated B cells, including the BAFF receptor (BAFF-R), the transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI) and the B cell maturation antigen (BCMA), were determined by flow cytometry. mRNA expression levels for the receptors were validated using Real-Time quantitative PCR. RESULTS HZ-activated monocytes released sBAFF and sAPRIL during the 72 h stimulation period. Increased mRNA encoding of their cognate receptors, BAFF-R, TACI, and BCMA, and increased HZ-specific IgG levels were also observed in HZ induction within the monocyte and B cell co-culture. The experiments under control conditions revealed that HZ alone could induce B cell culture to produce a small amount of the specific IgG compared with those in medium alone or rBAFF + rAPRIL + rIL-4. CONCLUSION Taken together, we suggest that in the TI response HZ stimulates monocyte and B cell co-culture to produce specific IgG through BAFF, APRIL and other independent complimentary signaling pathways.
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13
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Moncunill G, Mpina M, Nhabomba AJ, Aguilar R, Ayestaran A, Sanz H, Campo JJ, Jairoce C, Barrios D, Dong Y, Díez-Padrisa N, Fernandes JF, Abdulla S, Sacarlal J, Williams NA, Harezlak J, Mordmüller B, Agnandji ST, Aponte JJ, Daubenberger C, Valim C, Dobaño C. Distinct Helper T Cell Type 1 and 2 Responses Associated With Malaria Protection and Risk in RTS,S/AS01E Vaccinees. Clin Infect Dis 2018; 65:746-755. [PMID: 28505356 DOI: 10.1093/cid/cix429] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/04/2017] [Indexed: 12/13/2022] Open
Abstract
Background The RTS,S/AS01E malaria vaccine has moderate efficacy, lower in infants than children. Current efforts to enhance RTS,S/AS01E efficacy would benefit from learning about the vaccine-induced immunity and identifying correlates of malaria protection, which could, for instance, inform the choice of adjuvants. Here, we sought cellular immunity-based correlates of malaria protection and risk associated with RTS,S/AS01E vaccination. Methods We performed a matched case-control study nested within the multicenter African RTS,S/AS01E phase 3 trial. Children and infant samples from 57 clinical malaria cases (32 RTS,S/25 comparator vaccinees) and 152 controls without malaria (106 RTS,S/46 comparator vaccinees) were analyzed. We measured 30 markers by Luminex following RTS,S/AS01E antigen stimulation of cells 1 month postimmunization. Crude concentrations and ratios of antigen to background control were analyzed. Results Interleukin (IL) 2 and IL-5 ratios were associated with RTS,S/AS01E vaccination (adjusted P ≤ .01). IL-5 circumsporozoite protein (CSP) ratios, a helper T cell type 2 cytokine, correlated with higher odds of malaria in RTS,S/AS01E vaccinees (odds ratio, 1.17 per 10% increases of CSP ratios; P value adjusted for multiple testing = .03). In multimarker analysis, the helper T cell type 1 (TH1)-related markers interferon-γ, IL-15, and granulocyte-macrophage colony-stimulating factor protected from subsequent malaria, in contrast to IL-5 and RANTES, which increased the odds of malaria. Conclusions RTS,S/AS01E-induced IL-5 may be a surrogate of lack of protection, whereas TH1-related responses may be involved in protective mechanisms. Efforts to develop second-generation vaccine candidates may concentrate on adjuvants that modulate the immune system to support enhanced TH1 responses and decreased IL-5 responses.
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Affiliation(s)
- Gemma Moncunill
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | - Maxmillian Mpina
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Tanzania
| | | | - Ruth Aguilar
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - Aintzane Ayestaran
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - Héctor Sanz
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - Joseph J Campo
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | | | - Diana Barrios
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - Yan Dong
- Department of Epidemiology and Biostatistics, School of Public Health, Indiana University, Bloomington
| | - Núria Díez-Padrisa
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - José F Fernandes
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Gabon
| | | | - Jahit Sacarlal
- Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique.,Faculdade de Medicina da Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Nana A Williams
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain
| | - Jaroslaw Harezlak
- Department of Epidemiology and Biostatistics, School of Public Health, Indiana University, Bloomington
| | - Benjamin Mordmüller
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Gabon.,Institute of Tropical Medicine, German Center for Infection Research, University of Tübingen, Germany
| | - Selidji T Agnandji
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Gabon
| | - John J Aponte
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
| | - Claudia Daubenberger
- Swiss Tropical and Public Health Institute, Basel.,University of Basel, Switzerland
| | - Clarissa Valim
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing.,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Carlota Dobaño
- ISGlobal, Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, Catalonia, Spain.,Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
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Abstract
The candidate malaria vaccine RTS,S has demonstrated 45.7% efficacy over 18 months against all clinical disease in a phase-III field study of African children. RTS,S targets the circumsporozoite protein (CSP), which is expressed on the Plasmodium sporozoite during the pre-erythrocyte stage of its life-cycle; the stage between mosquito bite and liver infection. Early in the development of RTS,S, it was recognized that CSP-specific cell-mediated immunity (CMI) was required to complement CSP-specific antibody-mediated immunity. In reviewing RTS,S clinical studies, associations between protection and various types of CMI (CSP-specific CD4+ T cells and INF-γ ELISPOTs) have been identified, but not consistently. It is plausible that certain CD4+ T cells support antibody responses or co-operate with other immune-cell types to potentially elicit protection. However, the identities of vaccine correlates of protection, implicating either CSP-specific antibodies or T cells remain elusive, suggesting that RTS,S clinical trials may benefit from additional immunogenicity analyses that can be informed by the results of controlled human malaria infection studies.
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15
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Schussek S, Trieu A, Apte SH, Sidney J, Sette A, Doolan DL. Novel Plasmodium antigens identified via genome-based antibody screen induce protection associated with polyfunctional T cell responses. Sci Rep 2017; 7:15053. [PMID: 29118376 PMCID: PMC5678182 DOI: 10.1038/s41598-017-15354-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/25/2017] [Indexed: 12/13/2022] Open
Abstract
The development of vaccines against complex intracellular pathogens, such as Plasmodium spp., where protection is likely mediated by cellular immune responses, has proven elusive. The availability of whole genome, proteome and transcriptome data has the potential to advance rational vaccine development but yet there are no licensed vaccines against malaria based on antigens identified from genomic data. Here, we show that the Plasmodium yoelii orthologs of four Plasmodium falciparum proteins identified by an antibody-based genome-wide screening strategy induce a high degree of sterile infection-blocking protection against sporozoite challenge in a stringent rodent malaria model. Protection increased in multi-antigen formulations. Importantly, protection was highly correlated with the induction of multifunctional triple-positive T cells expressing high amounts of IFN-γ, IL-2 and TNF. These data demonstrate that antigens identified by serological screening are targets of multifunctional cellular immune responses that correlate with protection. Our results provide experimental validation for the concept of rational vaccine design from genomic sequence data.
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Affiliation(s)
- Sophie Schussek
- QIMR Berghofer Medical Research Institute, Infectious Diseases Programme, Herston, QLD 4006, Australia.,University of Queensland, School of Medicine, Herston, QLD 4006, Australia
| | - Angela Trieu
- QIMR Berghofer Medical Research Institute, Infectious Diseases Programme, Herston, QLD 4006, Australia
| | - Simon H Apte
- QIMR Berghofer Medical Research Institute, Infectious Diseases Programme, Herston, QLD 4006, Australia
| | - John Sidney
- La Jolla Institute of Allergy and Immunology, San Diego, CA, 92121, USA
| | - Alessandro Sette
- La Jolla Institute of Allergy and Immunology, San Diego, CA, 92121, USA
| | - Denise L Doolan
- QIMR Berghofer Medical Research Institute, Infectious Diseases Programme, Herston, QLD 4006, Australia. .,Centre for Biosecurity and Tropical Infectious Diseases, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4879, Australia.
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16
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Cabral-Miranda G, Heath MD, Gomes AC, Mohsen MO, Montoya-Diaz E, Salman AM, Atcheson E, Skinner MA, Kramer MF, Reyes-Sandoval A, Bachmann MF. Microcrystalline Tyrosine (MCT ®): A Depot Adjuvant in Licensed Allergy Immunotherapy Offers New Opportunities in Malaria. Vaccines (Basel) 2017; 5:vaccines5040032. [PMID: 28953265 PMCID: PMC5748599 DOI: 10.3390/vaccines5040032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/25/2017] [Accepted: 09/20/2017] [Indexed: 02/07/2023] Open
Abstract
Microcrystalline Tyrosine (MCT®) is a widely used proprietary depot excipient in specific immunotherapy for allergy. In the current study we assessed the potential of MCT to serve as an adjuvant in the development of a vaccine against malaria. To this end, we formulated the circumsporozoite protein (CSP) of P. vivax in MCT and compared the induced immune responses to CSP formulated in PBS or Alum. Both MCT and Alum strongly increased immunogenicity of CSP compared to PBS in both C57BL/6 and BALB/c mice. Challenge studies in mice using a chimeric P. bergei expressing CSP of P. vivax demonstrated clinically improved symptoms of malaria with CSP formulated in both MCT and Alum; protection was, however, more pronounced if CSP was formulated in MCT. Hence, MCT may be an attractive biodegradable adjuvant useful for the development of novel prophylactic vaccines.
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Affiliation(s)
- Gustavo Cabral-Miranda
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Matthew D Heath
- Allergy Therapeutics (UK) Ltd. Dominion Way, Worthing BN14 8SA, UK.
| | - Ariane C Gomes
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Mona O Mohsen
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Eduardo Montoya-Diaz
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Ahmed M Salman
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Erwan Atcheson
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Murray A Skinner
- Allergy Therapeutics (UK) Ltd. Dominion Way, Worthing BN14 8SA, UK.
| | | | - Arturo Reyes-Sandoval
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
| | - Martin F Bachmann
- Nuffield Department of Medicine, Centre for Cellular and Molecular Physiology (CCMP), The Jenner Institute, University of Oxford, Oxford OX3 7BN, UK.
- Immunology, RIA, Inselspital, University of Bern, 3010 Bern ,Switzerland.
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17
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Moncunill G, De Rosa SC, Ayestaran A, Nhabomba AJ, Mpina M, Cohen KW, Jairoce C, Rutishauser T, Campo JJ, Harezlak J, Sanz H, Díez-Padrisa N, Williams NA, Morris D, Aponte JJ, Valim C, Daubenberger C, Dobaño C, McElrath MJ. RTS,S/AS01E Malaria Vaccine Induces Memory and Polyfunctional T Cell Responses in a Pediatric African Phase III Trial. Front Immunol 2017; 8:1008. [PMID: 28878775 PMCID: PMC5572329 DOI: 10.3389/fimmu.2017.01008] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/07/2017] [Indexed: 12/30/2022] Open
Abstract
Comprehensive assessment of cellular responses to the RTS,S/AS01E vaccine is needed to understand potential correlates and ultimately mechanisms of protection against malaria disease. Cellular responses recognizing the RTS,S/AS01E-containing circumsporozoite protein (CSP) and Hepatitis B surface antigen (HBsAg) were assessed before and 1 month after primary vaccination by intracellular cytokine staining and 16-color flow cytometry in 105 RTS,S/AS01-vaccinated and 74 rabies-vaccinated participants (controls) in a pediatric phase III trial in Africa. RTS,S/AS01E-vaccinated children had significantly higher frequencies of CSP- and HBsAg-specific CD4+ T cells producing IL-2, TNF-α, and CD40L and HBsAg-specific CD4+ T producing IFN-γ and IL-17 than baseline and the control group. Vaccine-induced responses were identified in both central and effector memory (EM) compartments. EM CD4+ T cells expressing IL-4 and IL-21 were detected recognizing both vaccine antigens. Consistently higher response rates to both antigens in RTS,S/AS01E-vaccinated than comparator-vaccinated children were observed. RTS,S/AS01E induced polyfunctional CSP- and HBsAg-specific CD4+ T cells, with a greater degree of polyfunctionality in HBsAg responses. In conclusion, RTS,S/AS01E vaccine induces T cells of higher functional heterogeneity and polyfunctionality than previously characterized. Responses detected in memory CD4+ T cell compartments may provide correlates of RTS,S/AS01-induced immunity and duration of protection in future correlates of immunity studies.
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Affiliation(s)
- Gemma Moncunill
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain,Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique,*Correspondence: Gemma Moncunill,
| | - Stephen C. De Rosa
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States,Department of Laboratory Medicine, University of Washington, Seattle, WA, United States
| | - Aintzane Ayestaran
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain
| | | | - Maximillian Mpina
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, Tanzania
| | - Kristen W. Cohen
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Chenjerai Jairoce
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Tobias Rutishauser
- Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
| | - Joseph J. Campo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Jaroslaw Harezlak
- Department of Epidemiology and Biostatistics, School of Public Health-Bloomington, Indiana University, Bloomington, IN, United States
| | - Héctor Sanz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain
| | - Núria Díez-Padrisa
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain
| | - Nana Aba Williams
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain
| | - Daryl Morris
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - John J. Aponte
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain
| | - Clarissa Valim
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, MI, United States,Department of Immunology and Infectious Diseases, Harvard T.H. Chen School of Public Health, Boston, MA, United States
| | - Claudia Daubenberger
- Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
| | - Carlota Dobaño
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic – Universitat de Barcelona, Barcelona, Spain,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - M. Juliana McElrath
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States,Department of Medicine, University of Washington, Seattle, WA, United States
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Espinosa DA, Christensen D, Muñoz C, Singh S, Locke E, Andersen P, Zavala F. Robust antibody and CD8 + T-cell responses induced by P. falciparum CSP adsorbed to cationic liposomal adjuvant CAF09 confer sterilizing immunity against experimental rodent malaria infection. NPJ Vaccines 2017; 2. [PMID: 28936360 PMCID: PMC5603302 DOI: 10.1038/s41541-017-0011-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite several decades of extensive research, the development of a highly efficacious malaria vaccine has yet to be accomplished. While the RTS,S malaria vaccine candidate shows the potential to prevent a substantial number of clinical malaria cases, significant improvements in protective efficacy are still needed. Multiple studies have shown that RTS,S induces protective antibody and CD4+ T-cell responses, but limited or negligible CD8+ T cells. In this study, we evaluated the immunogenicity and protective capacity of full-length recombinant Plasmodium falciparum circumsporozoite protein administered with the novel cationic liposomal adjuvant system CAF09. Using newly developed transgenic rodent malaria parasites expressing the full-length Plasmodium falciparum circumsporozoite protein, we demonstrate that this liposome-based protein-in-adjuvant formulation is capable of inducing robust antibody and CD8+ T-cell responses that strongly inhibit parasite infection and development of liver stages, conferring durable sterilizing immunity. These findings underscore the potential of liposome-based adjuvants for inducing robust humoral and CD8+ T-cell responses and warrant further studies toward the development of novel subunit vaccine formulations with this adjuvant system. A vaccine consisting of parasitic proteins enveloped by fatty molecules provides comprehensive protection against malaria in a rodent model, Previous and current malaria vaccines concentrate on priming antibodies to recognize malarial infection, despite evidence that, by activating ‘killer’ CD8+ T cells, greater protection is conferred against the disease. Fidel Zavala, of the Johns Hopkins University, United States, and an international group of researchers developed their vaccine by encapsulating proteins from the malaria-causing parasite Plasmodium falciparum in fat-based carriers called liposomes. In past experiments, killer T cells recruited via this vaccine-type have effectively protected against other diseases. In this study, the vaccine induced both CD8+ T cell and antibody responses and provided significant immunity against P. falciparum-instigated malaria. As a highly efficacious vaccine against malaria is not yet available, this research will likely prove invaluable in guiding further studies.
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Affiliation(s)
- Diego A Espinosa
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Dennis Christensen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Christian Muñoz
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Emily Locke
- PATH Malaria Vaccine Initiative, Washington DC, USA
| | - Peter Andersen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
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Maskus DJ, Królik M, Bethke S, Spiegel H, Kapelski S, Seidel M, Addai-Mensah O, Reimann A, Klockenbring T, Barth S, Fischer R, Fendel R. Characterization of a novel inhibitory human monoclonal antibody directed against Plasmodium falciparum Apical Membrane Antigen 1. Sci Rep 2016; 6:39462. [PMID: 28000709 PMCID: PMC5175200 DOI: 10.1038/srep39462] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/22/2016] [Indexed: 01/07/2023] Open
Abstract
Malaria remains a major challenge to global health causing extensive morbidity and mortality. Yet, there is no efficient vaccine and the immune response remains incompletely understood. Apical Membrane Antigen 1 (AMA1), a leading vaccine candidate, plays a key role during merozoite invasion into erythrocytes by interacting with Rhoptry Neck Protein 2 (RON2). We generated a human anti-AMA1-antibody (humAbAMA1) by EBV-transformation of sorted B-lymphocytes from a Ghanaian donor and subsequent rescue of antibody variable regions. The antibody was expressed in Nicotiana benthamiana and in HEK239-6E, characterized for binding specificity and epitope, and analyzed for its inhibitory effect on Plasmodium falciparum. The generated humAbAMA1 shows an affinity of 106-135 pM. It inhibits the parasite strain 3D7A growth in vitro with an expression system-independent IC50-value of 35 μg/ml (95% confidence interval: 33 μg/ml-37 μg/ml), which is three to eight times lower than the IC50-values of inhibitory antibodies 4G2 and 1F9. The epitope was mapped to the close proximity of the RON2-peptide binding groove. Competition for binding between the RON2-peptide and humAbAMA1 was confirmed by surface plasmon resonance spectroscopy measurements. The particularly advantageous inhibitory activity of this fully human antibody might provide a basis for future therapeutic applications.
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Affiliation(s)
- Dominika J. Maskus
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
- Institute for Molecular Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Michał Królik
- Institute for Molecular Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Susanne Bethke
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Holger Spiegel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Stephanie Kapelski
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Melanie Seidel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Otchere Addai-Mensah
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
- Institute for Molecular Biotechnology, RWTH Aachen University, Aachen, Germany
- Faculty of Allied Health Sciences, Kwame Nkrumah University of Science and Technology, KNUST, Kumasi, Ghana
| | - Andreas Reimann
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Torsten Klockenbring
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Stefan Barth
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
- Institute for Applied Medical Engineering at RWTH Aachen University and Hospital, Department of Experimental Medicine and Immunotherapy, Aachen, Germany
| | - Rainer Fischer
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
- Institute for Molecular Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Rolf Fendel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
- Institute for Molecular Biotechnology, RWTH Aachen University, Aachen, Germany
- Institute for Applied Medical Engineering at RWTH Aachen University and Hospital, Department of Experimental Medicine and Immunotherapy, Aachen, Germany
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20
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21
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Zazo H, Colino CI, Lanao JM. Current applications of nanoparticles in infectious diseases. J Control Release 2016; 224:86-102. [PMID: 26772877 DOI: 10.1016/j.jconrel.2016.01.008] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Revised: 01/03/2016] [Accepted: 01/05/2016] [Indexed: 02/06/2023]
Abstract
For decades infections have been treated easily with drugs. However, in the 21st century, they may become lethal again owing to the development of antimicrobial resistance. Pathogens can become resistant by means of different mechanisms, such as increasing the time they spend in the intracellular environment, where drugs are unable to reach therapeutic levels. Moreover, drugs are also subject to certain problems that decrease their efficacy. This requires the use of high doses, and frequent administrations must be implemented, causing adverse side effects or toxicity. The use of nanoparticle systems can help to overcome such problems and increase drug efficacy. Accordingly, there is considerable current interest in their use as antimicrobial agents against different pathogens like bacteria, virus, fungi or parasites, multidrug-resistant strains and biofilms; as targeting vectors towards specific tissues; as vaccines and as theranostic systems. This review begins with an overview of the different types and characteristics of nanoparticles used to deliver drugs to the target, followed by a review of current research and clinical trials addressing the use of nanoparticles within the field of infectious diseases.
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Agnandji ST, Fernandes JF, Bache EB, Ramharter M. Clinical development of RTS,S/AS malaria vaccine: a systematic review of clinical Phase I-III trials. Future Microbiol 2015; 10:1553-78. [PMID: 26437872 DOI: 10.2217/fmb.15.90] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The first clinical Phase III trial evaluating a malaria vaccine was completed in December 2013 at 11 sites from seven sub-Saharan African countries. This systematic review assesses data of Phase I-III trials including malaria-naive adults and adults, children and infants from malaria endemic settings in sub-Saharan Africa. The main endpoint of this systematic review was an analysis of the consistency of efficacy and immunogenicity data from respective Phase I-III trials. In addition, safety data from a pooled analysis of RTS/AS Phase II trials and RTS,S/AS01 Phase III trial were reviewed. The RTS,S/AS01 malaria vaccine may become available on the market in the coming year. If so, further strategies should address challenges on how to optimize vaccine efficacy and implementation of RTS,S/AS01 vaccine within the framework of established malaria control measures.
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Affiliation(s)
- Selidji T Agnandji
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - José F Fernandes
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - Emmanuel B Bache
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany
| | - Michael Ramharter
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon, Hôpital Albert Schweitzer BP 118, Lambaréné, Gabon.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany, Wilhelmstraße 27, 72074 Tübingen, Germany.,Department of Medicine I, Division of Infectious Diseases & Tropical Medicine, Medical University of Vienna, Austria, Währinger Gürtel 18-20, 1190 Vienna, Austria
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Abstract
A vaccine for malaria is urgently required. The RTS,S vaccine represents major progress, but is only partially effective. Development of the next generation of highly effective vaccines requires elucidation of the protective immune response. Immunity to malaria is known to be complex, and pattern-based approaches such as global gene expression profiling are ideal for understanding response to vaccination and protection against disease. The availability of experimental sporozoite challenge in humans to test candidate malaria vaccines offers a precious opportunity unavailable for other current targets of vaccine research such as HIV, tuberculosis and Ebola. However, a limited number of transcriptional profiling studies in the context of malaria vaccine research have been published to date. This review outlines the background, existing studies, limits and opportunities for gene expression studies to accelerate malaria vaccine research.
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Affiliation(s)
- Susanna Dunachie
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK; Mahidol-Oxford Tropical Medicine Research Unit, 3rd Floor, 60th Anniversary Chalermprakiat Building, 420/6 Ratchawithi Road, Bangkok 10400, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research Building, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7FZ, UK.
| | - Adrian V S Hill
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Helen A Fletcher
- London School of Hygiene & Tropical Medicine, London, W1CE 7HT, UK; The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
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Leroux-Roels G, Leroux-Roels I, Clement F, Ofori-Anyinam O, Lievens M, Jongert E, Moris P, Ballou WR, Cohen J. Evaluation of the immune response to RTS,S/AS01 and RTS,S/AS02 adjuvanted vaccines: randomized, double-blind study in malaria-naïve adults. Hum Vaccin Immunother 2015; 10:2211-9. [PMID: 25424924 DOI: 10.4161/hv.29375] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
This phase II, randomized, double-blind study evaluated the immunogenicity of RTS,S vaccines containing Adjuvant System AS01 or AS02 as compared with non-adjuvanted RTS,S in healthy, malaria-naïve adults (NCT00443131). Thirty-six subjects were randomized (1:1:1) to receive RTS,S/AS01, RTS,S/AS02, or RTS,S/saline at months 0, 1, and 2. Antibody responses to Plasmodium falciparum circumsporozoite (CS) and hepatitis B surface (HBs) antigens were assessed and cell-mediated immune responses evaluated by flow cytometry using intracellular cytokine staining on peripheral blood mononuclear cells. Anti-CS antibody avidity was also characterized. Safety and reactogenicity after each vaccine dose were monitored. One month after the third vaccine dose, RTS,S/AS01 (160.3 EU/mL [95%CI: 114.1-225.4]) and RTS,S/AS02 (77.4 EU/mL (95%CI: 47.3-126.7)) recipients had significantly higher anti-CS antibody geometric mean titers (GMTs) than recipients of RTS,S/saline (12.2 EU/mL (95%CI: 4.8-30.7); P < 0.0001 and P = 0.0011, respectively). The anti-CS antibody GMT was significantly higher with RTS,S/AS01 than with RTS,S/AS02 (P = 0.0135). Anti-CS antibody avidity was in the same range in all groups. CS- and HBs-specific CD4(+) T cell responses were greater for both RTS,S/AS groups than for the RTS,S/saline group. Reactogenicity was in general higher for RTS,S/AS compared with RTS,S/saline. Most grade 3 solicited adverse events (AEs) were of short duration and grade 3 solicited general AEs were infrequent in the 3 groups. No serious adverse events were reported. In conclusion, in comparison with non-adjuvanted RTS,S, both RTS,S/AS vaccines exhibited better CS-specific immune responses. The anti-CS antibody response was significantly higher with RTS,S/AS01 than with RTS,S/AS02. The adjuvanted vaccines had acceptable safety profiles.
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Affiliation(s)
- Geert Leroux-Roels
- a Centre for Vaccinology (CEVAC); Ghent University and Ghent University Hospital; Ghent, Belgium
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25
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Abstract
Carbohydrates can be found on the cell surface of nearly every cell ranging from bacteria to fungi right up to mammalian cells. Carbohydrates and their interactions with carbohydrate-binding proteins play crucial roles in multiple biological processes including immunity, homeostasis, cellular communication, cell migration, and the regulation of serum glycoprotein levels. In the last decades, the interest in exploiting the biological activity of glycans as vaccine components has considerably increased. On the one hand, carbohydrates display epitopes to generate protective antibodies against pathogen-derived cell wall structures and on the other hand, glycans have the potential to stimulate the immune system; thus they can act as potent vaccine adjuvants.An effective vaccine consists of two major components, the vaccine antigen and an adjuvant. The vaccine antigen is an original or modified part of the pathogen that causes the disease. The immune response triggered by vaccination should induce antigen-specific plasma cells secreting protective antibodies as well as the development of memory T and B cells. Carbohydrate structures on pathogens represent an important class of antigens that can activate B cells to produce protective anti-carbohydrate antibodies in adults. A major breakthrough in vaccine development was the design of conjugate vaccines that evoke protective antibody responses against encapsulated bacteria strains such as Haemophilus influenzae, Streptococcus pneumoniae, or Neisseria meningitidis in adults, but also in young children. The first part of this chapter focuses on immune responses triggered by carbohydrate-based vaccines. The second part of the chapter discusses the immunological mechanisms of carbohydrate-based adjuvants to increase the immunogenicity of vaccines.
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Affiliation(s)
- Stephanie Zimmermann
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany,
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26
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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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Hodgson SH, Ewer KJ, Bliss CM, Edwards NJ, Rampling T, Anagnostou NA, de Barra E, Havelock T, Bowyer G, Poulton ID, de Cassan S, Longley R, Illingworth JJ, Douglas AD, Mange PB, Collins KA, Roberts R, Gerry S, Berrie E, Moyle S, Colloca S, Cortese R, Sinden RE, Gilbert SC, Bejon P, Lawrie AM, Nicosia A, Faust SN, Hill AVS. Evaluation of the efficacy of ChAd63-MVA vectored vaccines expressing circumsporozoite protein and ME-TRAP against controlled human malaria infection in malaria-naive individuals. J Infect Dis 2014; 211:1076-86. [PMID: 25336730 PMCID: PMC4354983 DOI: 10.1093/infdis/jiu579] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background. Circumsporozoite protein (CS) is the antigenic target for RTS,S, the most advanced malaria vaccine to date. Heterologous prime-boost with the viral vectors simian adenovirus 63 (ChAd63)-modified vaccinia virus Ankara (MVA) is the most potent inducer of T-cells in humans, demonstrating significant efficacy when expressing the preerythrocytic antigen insert multiple epitope–thrombospondin-related adhesion protein (ME-TRAP). We hypothesized that ChAd63-MVA containing CS may result in a significant clinical protective efficacy. Methods. We conducted an open-label, 2-site, partially randomized Plasmodium falciparum sporozoite controlled human malaria infection (CHMI) study to compare the clinical efficacy of ChAd63-MVA CS with ChAd63-MVA ME-TRAP. Results. One of 15 vaccinees (7%) receiving ChAd63-MVA CS and 2 of 15 (13%) receiving ChAd63-MVA ME-TRAP achieved sterile protection after CHMI. Three of 15 vaccinees (20%) receiving ChAd63-MVA CS and 5 of 15 (33%) receiving ChAd63-MVA ME-TRAP demonstrated a delay in time to treatment, compared with unvaccinated controls. In quantitative polymerase chain reaction analyses, ChAd63-MVA CS was estimated to reduce the liver parasite burden by 69%–79%, compared with 79%–84% for ChAd63-MVA ME-TRAP. Conclusions. ChAd63-MVA CS does reduce the liver parasite burden, but ChAd63-MVA ME-TRAP remains the most promising antigenic insert for a vectored liver-stage vaccine. Detailed analyses of parasite kinetics may allow detection of smaller but biologically important differences in vaccine efficacy that can influence future vaccine development. Clinical Trials Registration. NCT01623557.
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Affiliation(s)
| | | | | | | | | | | | - Eoghan de Barra
- Jenner Institute Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Tom Havelock
- NIHR Wellcome Trust Clinical Research Facility, University of Southampton and University Hospital Southampton NHS Foundation Trust
| | | | | | | | | | | | | | | | | | | | | | - Eleanor Berrie
- Clinical Biomanufacturing Facility, University of Oxford
| | - Sarah Moyle
- Clinical Biomanufacturing Facility, University of Oxford
| | | | | | - Robert E Sinden
- Jenner Institute Division of Cell and Molecular Biology, Imperial College London, United Kingdom
| | | | - Philip Bejon
- Centre for Geographical Medical Research (Coast), Kenya Medical Research Institute-Wellcome Trust, Kilifi
| | | | - Alfredo Nicosia
- Okairos, Rome CEINGE Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Italy
| | - Saul N Faust
- NIHR Wellcome Trust Clinical Research Facility, University of Southampton and University Hospital Southampton NHS Foundation Trust
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Bourguignon P, Clément F, Renaud F, Le Bras V, Koutsoukos M, Burny W, Moris P, Lorin C, Collard A, Leroux-Roels G, Roman F, Janssens M, Vandekerckhove L. Processing of blood samples influences PBMC viability and outcome of cell-mediated immune responses in antiretroviral therapy-naïve HIV-1-infected patients. J Immunol Methods 2014; 414:1-10. [PMID: 25224748 DOI: 10.1016/j.jim.2014.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 09/01/2014] [Accepted: 09/05/2014] [Indexed: 12/22/2022]
Abstract
Intracellular cytokine staining (ICS) assay is increasingly used in vaccine clinical trials to measure antigen-specific T-cell mediated immune (CMI) responses in cryopreserved peripheral blood mononuclear cells (PBMCs) and whole blood. However, recent observations indicate that several parameters involved in blood processing can impact PBMC viability and CMI responses, especially in antiretroviral therapy (ART)-naïve HIV-1-infected individuals. In this phase I study (NCT01610427), we collected blood samples from 22 ART-naïve HIV-1-infected adults. PBMCs were isolated and processed for ICS assay. The individual and combined effects of the following parameters were investigated: time between blood collection and PBMC processing (time-to-process: 2, 7 or 24 h); time between PBMC thawing and initiation of in vitro stimulation with HIV-1 antigens (resting-time: 0, 2, 6 and 18 h); and duration of antigen-stimulation in PBMC cultures (stimulation-time: 6h or overnight). The cell recovery after thawing, cell viability after ICS and magnitude of HIV-specific CD8(+) T-cell responses were considered to determine the optimal combination of process conditions. The impact of time-to-process (2 or 4 h) on HIV-specific CD8(+) T-cell responses was also assessed in a whole blood ICS assay. A higher quality of cells in terms of recovery and viability (up to 81% and >80% respectively) was obtained with shorter time-to-process (less than 7 h) and resting-time (less than 2 h) intervals. Longer (overnight) rather than shorter (6 h) stimulation-time intervals increased the frequency of CD8(+)-specific T-cell responses using ICS in PBMCs without change of the functionality. The CD8(+) specific T-cell responses detected using fresh whole blood showed a good correlation with the responses detected using frozen PBMCs. Our results support the need of standardized procedures for the evaluation of CMI responses, especially in HIV-1-infected, ART-naïve patients.
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Affiliation(s)
| | - Frédéric Clément
- Center for Vaccinology, Ghent University and Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - Frédéric Renaud
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Vivien Le Bras
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | | | - Wivine Burny
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Philippe Moris
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Clarisse Lorin
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Alix Collard
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Geert Leroux-Roels
- Center for Vaccinology, Ghent University and Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
| | - François Roman
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Michel Janssens
- GlaxoSmithKline Vaccines, Rue de l'institut 89, Rixensart 1330, Belgium.
| | - Linos Vandekerckhove
- ARC (AIDS Reference Center), Department of Internal Medicine, Ghent University and Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
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Campo JJ, Sacarlal J, Aponte JJ, Aide P, Nhabomba AJ, Dobaño C, Alonso PL. Duration of vaccine efficacy against malaria: 5th year of follow-up in children vaccinated with RTS,S/AS02 in Mozambique. Vaccine 2014; 32:2209-16. [PMID: 24631081 DOI: 10.1016/j.vaccine.2014.02.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 12/18/2013] [Accepted: 02/12/2014] [Indexed: 02/07/2023]
Abstract
A primary concern for the RTS,S malaria vaccine candidate is duration of protection. The ongoing Phase III trial reported evidence of waning efficacy within the first year following vaccination. Multiple Phase IIb trials demonstrated early waning of efficacy. The longest duration of protection for RTS,S recorded to date was in a trial of a cohort of 1605 Mozambican children age 1-4 yr at the time of immunization (C1), which showed an overall efficacy against clinical malaria of 30.5% over 43 subsequent months of surveillance. A significant reduction in parasite prevalence in RTS,S vaccinees indicated that the vaccine continued to protect at the end of this period. Although follow-up for recording incident cases of clinical malaria was stopped at 45 months, we were interested in evidence of further durability of protection, and revisited the cohort at 63 months, recording the secondary trial endpoint, prevalence of asexual Plasmodium falciparum parasitemia, in the RTS,S and comparator vaccine groups as a proxy for efficacy. As a comparator, we also visited the contemporaneous cohort of 417 children (C2), which showed waning efficacy after 6 months of follow-up. We also assessed anti-circumsporozoite antibody titers. These results were compared with those of other Phase IIb trials. Prevalence of parasitemia was not significantly lower in the RTS,S/AS02 group compared to comparator groups in C1 (57 [119%] Vs 62 [128%]; p=0.696) or C2 (30 [226%] Vs 35 [276%]; p=0.391), despite elevated antibody titers, suggesting that protection did not extend to 5 years after vaccination. This is in contrast to the earlier assessment of parasitemia in C1, where a 34% lower prevalence of parasitemia was observed in the RTS,S/AS02 group at month 45. Comparison with other Phase II trials highlights a complex relationship between efficacy, age and transmission intensity. RTS,S/AS02 provided partial protection from clinical malaria for at least 3.5 years in C1. Duration of protection may depend on environmental circumstances, such as changing malaria transmission, and special attention should be given in the Phase III trial to identifying factors that modify longevity of protection.
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Abstract
Pre-erythrocytic malaria vaccines target Plasmodium during its sporozoite and liver stages, and can prevent progression to blood-stage disease, which causes a million deaths each year. Whole organism sporozoite vaccines induce sterile immunity in animals and humans and guide subunit vaccine development. A recombinant protein-in-adjuvant pre-erythrocytic vaccine called RTS,S reduces clinical malaria without preventing infection in field studies and additional antigens may be required to achieve sterile immunity. Although few vaccine antigens have progressed to human testing, new insights into parasite biology, expression profiles and immunobiology have offered new targets for intervention. Future advances require human trials of additional antigens, as well as platforms to induce the durable antibody and cellular responses including CD8(+) T cells that contribute to sterile protection.
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Affiliation(s)
- Patrick E Duffy
- Laboratory of Malaria Immunology & Vaccinology, Division of Intramural Research, NIAID, NIH, Rockville, MD, USA.
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Cashins SD, Grogan LF, McFadden M, Hunter D, Harlow PS, Berger L, Skerratt LF. Prior infection does not improve survival against the amphibian disease Chytridiomycosis. PLoS One 2013; 8:e56747. [PMID: 23451076 DOI: 10.1371/journal.pone.0056747] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 01/04/2013] [Indexed: 11/18/2022] Open
Abstract
Many amphibians have declined globally due to introduction of the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Hundreds of species, many in well-protected habitats, remain as small populations at risk of extinction. Currently the only proven conservation strategy is to maintain species in captivity to be reintroduced at a later date. However, methods to abate the disease in the wild are urgently needed so that reintroduced and wild animals can survive in the presence of Bd. Vaccination has been widely suggested as a potential strategy to improve survival. We used captive-bred offspring of critically endangered booroolong frogs (Litoria booroolongensis) to test if vaccination in the form of prior infection improves survival following re exposure. We infected frogs with a local Bd isolate, cleared infection after 30 days (d) using itraconazole just prior to the onset of clinical signs, and then re-exposed animals to Bd at 110 d. We found prior exposure had no effect on survival or infection intensities, clearly showing that real infections do not stimulate a protective adaptive immune response in this species. This result supports recent studies suggesting Bd may evade or suppress host immune functions. Our results suggest vaccination is unlikely to be useful in mitigating chytridiomycosis. However, survival of some individuals from all experimental groups indicates existence of protective innate immunity. Understanding and promoting this innate resistance holds potential for enabling species recovery.
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Riley EM, Stewart VA. Immune mechanisms in malaria: new insights in vaccine development. Nat Med 2013; 19:168-78. [DOI: 10.1038/nm.3083] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 01/07/2013] [Indexed: 02/07/2023]
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Ndungu FM, Mwacharo J, Kimani D, Kai O, Moris P, Jongert E, Vekemans J, Olotu A, Bejon P. A statistical interaction between circumsporozoite protein-specific T cell and antibody responses and risk of clinical malaria episodes following vaccination with RTS,S/AS01E. PLoS One 2012; 7:e52870. [PMID: 23300801 PMCID: PMC3531328 DOI: 10.1371/journal.pone.0052870] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 11/21/2012] [Indexed: 11/19/2022] Open
Abstract
The candidate malaria vaccine RTS,S/AS01E provides significant but partial protection from clinical malaria. On in vitro circumsporozoite protein (CSP) peptide stimulation and intra-cellular cytokine staining of whole blood taken from 407 5–17 month-old children in a phase IIb trial of RTS,S/AS01E, we identified significantly increased frequencies of two CSP-specific CD4+ T cells phenotypes among RTS,S/AS01E vaccinees (IFNγ-IL2+TNF− and IFNγ-IL2+TNF+ CD4+ T cells), and increased frequency of IFNγ-IL2-TNF+ CD4+ T cells after natural exposure. All these T cells phenotypes were individually associated with reductions in the risk of clinical malaria, but IFNγ-IL2-TNF+ CD4+ T cells independently predicted reduced risk of clinical malaria on multi-variable analysis (HR = 0.29, 95% confidence intervals 0.15–0.54, p<0.0005). Furthermore, there was a strongly significant synergistic interaction between CSP-specific IFNγ-IL2-TNF+ CD4+ T cells and anti-CSP antibodies in determining protection against clinical malaria (p = 0.002). Vaccination strategies that combine potent cellular and antibody responses may enhance protection against malaria.
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Affiliation(s)
- Francis M Ndungu
- Kenya Medical Research Institute, Centre for Geographical Medical Research-Coast, Kilifi, Kenya.
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Horowitz A, Hafalla JCR, King E, Lusingu J, Dekker D, Leach A, Moris P, Cohen J, Vekemans J, Villafana T, Corran PH, Bejon P, Drakeley CJ, von Seidlein L, Riley EM. Antigen-specific IL-2 secretion correlates with NK cell responses after immunization of Tanzanian children with the RTS,S/AS01 malaria vaccine. J Immunol 2012; 188:5054-62. [PMID: 22504653 DOI: 10.4049/jimmunol.1102710] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
RTS,S/AS01, a vaccine targeting pre-erythrocytic stages of Plasmodium falciparum, is undergoing clinical trials. We report an analysis of cellular immune response to component Ags of RTS,S-hepatitis B surface Ag (HBs) and P. falciparum circumsporozoite (CS) protein-among Tanzanian children in a phase IIb RTS,S/AS01(E) trial. RTS,S/AS01 (E) vaccinees make stronger T cell IFN-γ, CD69, and CD25 responses to HBs peptides than do controls, indicating that RTS,S boosts pre-existing HBs responses. T cell CD69 and CD25 responses to CS and CS-specific secreted IL-2 were augmented by RTS,S vaccination. Importantly, more than 50% of peptide-induced IFN-γ(+) lymphocytes were NK cells, and the magnitude of the NK cell CD69 response to HBs peptides correlated with secreted IL-2 concentration. CD69 and CD25 expression and IL-2 secretion may represent sensitive markers of RTS,S-induced, CS-specific T cells. The potential for T cell-derived IL-2 to augment NK cell activation in RTS,S-vaccinated individuals, and the relevance of this for protection, needs to be explored further.
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Affiliation(s)
- Amir Horowitz
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom
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Kaushansky A, Rezakhani N, Mann H, Kappe SHI. Development of a quantitative flow cytometry-based assay to assess infection by Plasmodium falciparum sporozoites. Mol Biochem Parasitol 2012; 183:100-3. [PMID: 22342965 DOI: 10.1016/j.molbiopara.2012.01.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 01/31/2012] [Indexed: 10/14/2022]
Abstract
The human malaria parasite Plasmodium falciparum causes the most deadly parasitic disease worldwide, necessitating the development of interventions that block infection. Yet, preclinical assays to measure inhibition of infection date from the 1980s and are based on microscopy. Here, we describe the development of a simple flow cytometric assay that can be used to quantitatively assess P. falciparum sporozoite infection in vitro in low and medium throughput. We demonstrate the utility of this assay for assessing both drug inhibition of infection and measuring efficacy of antibodies in blocking parasite infection. This methodology will aid in assessing functional antibody responses to vaccination and novel drugs that prevent mosquito-to-man transmission of malaria.
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Olotu A, Moris P, Mwacharo J, Vekemans J, Kimani D, Janssens M, Kai O, Jongert E, Lievens M, Leach A, Villafana T, Savarese B, Marsh K, Cohen J, Bejon P. Circumsporozoite-specific T cell responses in children vaccinated with RTS,S/AS01E and protection against P falciparum clinical malaria. PLoS One 2011; 6:e25786. [PMID: 21998698 PMCID: PMC3188575 DOI: 10.1371/journal.pone.0025786] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 09/09/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND RTS,S/AS01(E) is the lead candidate pre-erythrocytic malaria vaccine. In Phase IIb field trials the safety profile was acceptable and the efficacy was 53% (95%CI 31%-72%) for protecting children against clinical malaria caused by P. falciparum. We studied CS-specific T cell responses in order to identify correlates of protection. METHODS AND FINDINGS We used intracellular cytokine staining (for IL2, IFNγ, and TNFα), ex-vivo ELISPOTs (IFNγ and IL2) and IFNγ cultured ELISPOT assays to characterize the CS-specific cellular responses in 407 children (5-17 months of age) in a phase IIb randomized controlled trial of RTS,S/AS01(E) (NCT00380393). RTS,S/ AS01(E) vaccinees had higher frequencies of CS-specific CD4+ T cells producing IFNγ, TNFα or IL2 compared to control vaccinees. In a multivariable analysis TNFα(+) CD4(+) T cells were independently associated with a reduced risk for clinical malaria among RTS,S/AS01(E) vaccinees (HR = 0.64, 95%CI 0.49-0.86, p = 0.002). There was a non-significant tendency towards reduced risk among control vaccinees (HR = 0.80, 95%CI 0.62-1.03, p = 0.084), albeit with lower CS-specific T cell frequencies and higher rates of clinical malaria. When data from both RTS,S/AS01(E) vaccinees and control vaccinees were combined (with adjusting for vaccination group), the HR was 0.74 (95%CI 0.62-0.89, p = 0.001). After a Bonferroni correction for multiple comparisons (n-18), the finding was still significant at p = 0.018. There was no significant correlation between cultured or ex vivo ELISPOT data and protection from clinical malaria. The combination of TNFα(+) CD4(+) T cells and anti-CS antibody statistically accounted for the protective effect of vaccination in a Cox regression model. CONCLUSIONS RTS,S/AS01(E) induces CS-specific Th1 T cell responses in young children living in a malaria endemic area. The combination of anti-CS antibody concentrations titers and CS-specific TNFα(+) CD4(+) T cells could account for the level of protection conferred by RTS,S/AS01(E). The correlation between CS-specific TNFα(+) CD4(+) T cells and protection needs confirmation in other datasets.
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Affiliation(s)
- Ally Olotu
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
| | | | - Jedidah Mwacharo
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
| | | | - Domtila Kimani
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
| | | | - Oscar Kai
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
| | | | | | | | - Tonya Villafana
- PATH Malaria Vaccine Initiative (MVI), Bethesda, Maryland, United States of America
- MedImmune, LLC, Gaithersburg, Maryland, United States of America
| | - Barbara Savarese
- PATH Malaria Vaccine Initiative (MVI), Bethesda, Maryland, United States of America
| | - Kevin Marsh
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
- Centre for Clinical Vaccinology and Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | - Philip Bejon
- Kenya Medical Research Institute/ Wellcome Trust Programme, Centre for Geographic Medicine Research, Coast, Kilifi, Kenya
- Centre for Clinical Vaccinology and Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- * E-mail:
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