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Ventocilla JA, Tapia LL, Ponce R, Franco A, Leelawong M, Aguiar JC, Baldeviano GC, Wilder BK. Evaluation of naturally acquired immune responses against novel pre-erythrocytic Plasmodium vivax proteins in a low endemic malaria population located in the Peruvian Amazon Basin. Malar J 2024; 23:163. [PMID: 38783317 PMCID: PMC11118720 DOI: 10.1186/s12936-024-04978-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 05/09/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND Plasmodium vivax represents the most geographically widespread human malaria parasite affecting civilian and military populations in endemic areas. Targeting the pre-erythrocytic (PE) stage of the parasite life cycle is especially appealing for developing P. vivax vaccines as it would prevent disease and transmission. Here, naturally acquired immunity to a panel of P. vivax PE antigens was explored, which may facilitate vaccine development and lead to a better understanding of naturally acquired PE immunity. METHODS Twelve P. vivax PE antigens orthologous to a panel of P. falciparum antigens previously identified as highly immunogenic in protected subjects after immunization with radiation attenuated sporozoites (RAS) were used for evaluation of humoral and cellular immunity by ELISA and IFN-γ ELISpot. Samples from P. vivax infected individuals (n = 76) from a low endemic malaria region in the Peruvian Amazon Basin were used. RESULTS In those clinical samples, all PE antigens evaluated showed positive IgG antibody reactivity with a variable prevalence of 58-99% in recently P. vivax diagnosed patients. The magnitude of the IgG antibody response against PE antigens was lower compared with blood stage antigens MSP1 and DBP-II, although antibody levels persisted better for PE antigens (average decrease of 6% for PE antigens and 43% for MSP1, p < 0.05). Higher IgG antibodies was associated with one or more previous malaria episodes only for blood stage antigens (p < 0.001). High IgG responders across PE and blood stage antigens showed significantly lower parasitaemia compared to low IgG responders (median 1,921 vs 4,663 par/µl, p < 0.05). In a subgroup of volunteers (n = 17),positive IFN-γ T cell response by ELISPOT was observed in 35% vs 9-35% against blood stage MSP1 and PE antigens, respectively, but no correlation with IgG responses. CONCLUSIONS These results demonstrate clear humoral and T cell responses against P. vivax PE antigens in individuals naturally infected with P. vivax. These data identify novel attractive PE antigens suitable for use in the potential development and selection of new malaria vaccine candidates which can be used as a part of malaria prevention strategies in civilian and military populations living in P. vivax endemic areas.
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Affiliation(s)
- Julio A Ventocilla
- Vysnova Partners Inc., Bethesda, USA
- Universidad Peruana Cayetano Heredia, Lima, Peru
| | - L Lorena Tapia
- U.S. Naval Medical Research Unit South, Lima-Peru (NAMRU SOUTH), Bellavista, Peru
| | | | | | - Mindy Leelawong
- U.S. Naval Medical Research Unit South, Lima-Peru (NAMRU SOUTH), Bellavista, Peru
- NYC Department of Health and Mental Hygiene, Long Island City, USA
| | | | - G Christian Baldeviano
- U.S. Naval Medical Research Unit South, Lima-Peru (NAMRU SOUTH), Bellavista, Peru
- Bluebird Bio, Inc, Somerville, USA
| | - Brandon K Wilder
- U.S. Naval Medical Research Unit South, Lima-Peru (NAMRU SOUTH), Bellavista, Peru.
- Oregon Health & Science University, Portland, USA.
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Thawornpan P, Nicholas J, Malee C, Kochayoo P, Wangriatisak K, Tianpothong P, Ntumngia FB, J. Barnes S, H. Adams J, Chootong P. Longitudinal analysis of antibody responses to Plasmodium vivax sporozoite antigens following natural infection. PLoS Negl Trop Dis 2024; 18:e0011907. [PMID: 38277340 PMCID: PMC10817200 DOI: 10.1371/journal.pntd.0011907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 01/08/2024] [Indexed: 01/28/2024] Open
Abstract
BACKGROUND P. vivax malaria is a major global health burden hindering social and economic development throughout many tropical and sub-tropical countries. Pre-erythrocytic (PE) vaccines emerge as an attractive approach for the control and elimination of malaria infection. Therefore, evaluating the magnitude, longevity and prevalence of naturally acquired IgG antibody responses against PE candidate antigens is useful for vaccine design. METHODOLOGY/PRINCIPAL FINDINGS The antigenicity of five recombinant PE antigens (PvCSP-VK210, PvSSP3, PvM2-MAEBL, PvCelTOS and PvSPECT1) was evaluated in plasma samples from individuals residing in low transmission areas in Thailand (Ranong and Chumphon Provinces). The samples were collected at the time of acute vivax malaria and 90, 270 and 360 days later. The prevalence, magnitude and longevity of total IgG and IgG subclasses were determined for each antigen using the longitudinal data. Our results showed that seropositivity of all tested PE antigens was detected during infection in at least some subjects; anti-PvCSP-VK210 and anti-PvCelTOS antibodies were the most frequent. Titers of these antibodies declined during the year of follow up, but notably seropositivity persisted. Among seropositive subjects at post-infection, high number of subjects possessed antibodies against PvCSP-VK210. Anti-PvSSP3 antibody responses had the longest half-life. IgG subclass profiling showed that the predominant subclasses were IgG1 and IgG3 (cytophilic antibodies), tending to remain detectable for at least 360 days after infection. CONCLUSIONS/SIGNIFICANCE The present study demonstrated the magnitude and longevity of serological responses to multiple PE antigens of P. vivax after natural infection. This knowledge could contribute to the design of an effective P. vivax vaccine.
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Affiliation(s)
- Pongsakorn Thawornpan
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Justin Nicholas
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Chayapat Malee
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Piyawan Kochayoo
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Kittikorn Wangriatisak
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Pachara Tianpothong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Francis Babila Ntumngia
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Samantha J. Barnes
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - John H. Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Patchanee Chootong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
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Nicholas J, De SL, Thawornpan P, Brashear AM, Kolli SK, Subramani PA, Barnes SJ, Cui L, Chootong P, Ntumngia FB, Adams JH. Preliminary characterization of Plasmodium vivax sporozoite antigens as pre-erythrocytic vaccine candidates. PLoS Negl Trop Dis 2023; 17:e0011598. [PMID: 37703302 PMCID: PMC10519608 DOI: 10.1371/journal.pntd.0011598] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/25/2023] [Accepted: 08/15/2023] [Indexed: 09/15/2023] Open
Abstract
Plasmodium vivax pre-erythrocytic (PE) vaccine research has lagged far behind efforts to develop Plasmodium falciparum vaccines. There is a critical gap in our knowledge of PE antigen targets that can induce functionally inhibitory neutralizing antibody responses. To overcome this gap and guide the selection of potential PE vaccine candidates, we considered key characteristics such as surface exposure, essentiality to infectivity and liver stage development, expression as recombinant proteins, and functional immunogenicity. Selected P. vivax sporozoite antigens were surface sporozoite protein 3 (SSP3), sporozoite microneme protein essential for cell traversal (SPECT1), sporozoite surface protein essential for liver-stage development (SPELD), and M2 domain of MAEBL. Sequence analysis revealed little variation occurred in putative B-cell and T-cell epitopes of the PE candidates. Each antigen was tested for expression as refolded recombinant proteins using an established bacterial expression platform and only SPELD failed. The successfully expressed antigens were immunogenic in vaccinated laboratory mice and were positively reactive with serum antibodies of P. vivax-exposed residents living in an endemic region in Thailand. Vaccine immune antisera were tested for reactivity to native sporozoite proteins and for their potential vaccine efficacy using an in vitro inhibition of liver stage development assay in primary human hepatocytes quantified on day 6 post-infection by high content imaging analysis. The anti-PE sera produced significant inhibition of P. vivax sporozoite invasion and liver stage development. This report provides an initial characterization of potential new PE candidates for a future P. vivax vaccine.
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Affiliation(s)
- Justin Nicholas
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Sai Lata De
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Pongsakorn Thawornpan
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Awtum M. Brashear
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Surendra Kumar Kolli
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Pradeep Annamalai Subramani
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Samantha J. Barnes
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Liwang Cui
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Patchanee Chootong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | - Francis Babila Ntumngia
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - John H. Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America
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Richie TL, Church LWP, Murshedkar T, Billingsley PF, James ER, Chen MC, Abebe Y, KC N, Chakravarty S, Dolberg D, Healy SA, Diawara H, Sissoko MS, Sagara I, Cook DM, Epstein JE, Mordmüller B, Kapulu M, Kreidenweiss A, Franke-Fayard B, Agnandji ST, López Mikue MSA, McCall MBB, Steinhardt L, Oneko M, Olotu A, Vaughan AM, Kublin JG, Murphy SC, Jongo S, Tanner M, Sirima SB, Laurens MB, Daubenberger C, Silva JC, Lyke KE, Janse CJ, Roestenberg M, Sauerwein RW, Abdulla S, Dicko A, Kappe SHI, Lee Sim BK, Duffy PE, Kremsner PG, Hoffman SL. Sporozoite immunization: innovative translational science to support the fight against malaria. Expert Rev Vaccines 2023; 22:964-1007. [PMID: 37571809 PMCID: PMC10949369 DOI: 10.1080/14760584.2023.2245890] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 08/04/2023] [Indexed: 08/13/2023]
Abstract
INTRODUCTION Malaria, a devastating febrile illness caused by protozoan parasites, sickened 247,000,000 people in 2021 and killed 619,000, mostly children and pregnant women in sub-Saharan Africa. A highly effective vaccine is urgently needed, especially for Plasmodium falciparum (Pf), the deadliest human malaria parasite. AREAS COVERED Sporozoites (SPZ), the parasite stage transmitted by Anopheles mosquitoes to humans, are the only vaccine immunogen achieving >90% efficacy against Pf infection. This review describes >30 clinical trials of PfSPZ vaccines in the U.S.A., Europe, Africa, and Asia, based on first-hand knowledge of the trials and PubMed searches of 'sporozoites,' 'malaria,' and 'vaccines.' EXPERT OPINION First generation (radiation-attenuated) PfSPZ vaccines are safe, well tolerated, 80-100% efficacious against homologous controlled human malaria infection (CHMI) and provide 18-19 months protection without boosting in Africa. Second generation chemo-attenuated PfSPZ are more potent, 100% efficacious against stringent heterologous (variant strain) CHMI, but require a co-administered drug, raising safety concerns. Third generation, late liver stage-arresting, replication competent (LARC), genetically-attenuated PfSPZ are expected to be both safe and highly efficacious. Overall, PfSPZ vaccines meet safety, tolerability, and efficacy requirements for protecting pregnant women and travelers exposed to Pf in Africa, with licensure for these populations possible within 5 years. Protecting children and mass vaccination programs to block transmission and eliminate malaria are long-term objectives.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Sara A. Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Halimatou Diawara
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamadou S. Sissoko
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - David M. Cook
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Judith E. Epstein
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Benjamin Mordmüller
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Melissa Kapulu
- Biosciences Department, Kenya Medical Research Institute KEMRI-Wellcome Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Andrea Kreidenweiss
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | | | - Selidji T. Agnandji
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | | | - Matthew B. B. McCall
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Laura Steinhardt
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Martina Oneko
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - Ally Olotu
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Ashley M. Vaughan
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - James G. Kublin
- Department of Global Health, University of Washington, Seattle, WA, USA
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Sean C. Murphy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
- Center for Emerging and Re-emerging Infectious Diseases and Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Said Jongo
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Marcel Tanner
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Matthew B. Laurens
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Claudia Daubenberger
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Joana C. Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kirsten E. Lyke
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Chris J. Janse
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Meta Roestenberg
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Robert W. Sauerwein
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Salim Abdulla
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Alassane Dicko
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | | | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Peter G. Kremsner
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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Parreira KS, Scarpelli P, Rezende Lima W, Garcia RS. Contribution of Transcriptome to Elucidate the Biology of Plasmodium spp. Curr Top Med Chem 2022; 22:169-187. [PMID: 35021974 DOI: 10.2174/1568026622666220111140803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/22/2021] [Accepted: 12/26/2021] [Indexed: 11/22/2022]
Abstract
In the present review, we discuss some of the new technologies that have been applied to elucidate how Plasmodium spp escape from the immune system and subvert the host physiology to orchestrate the regulation of its biological pathways. Our manuscript describes how techniques such as microarray approaches, RNA-Seq and single-cell RNA sequencing have contributed to the discovery of transcripts and changed the concept of gene expression regulation in closely related malaria parasite species. Moreover, the text highlights the contributions of high-throughput RNA sequencing for the current knowledge of malaria parasite biology, physiology, vaccine target and the revelation of new players in parasite signaling.
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Affiliation(s)
| | - Pedro Scarpelli
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo - USP, São Paulo, Brazil
| | - Wânia Rezende Lima
- Departamento de Medicina, Instituto de Biotecnologia-Universidade Federal de Catalão
| | - R S Garcia
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo - USP, São Paulo, Brazil
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Sedegah M, Hollingdale MR, Ganeshan H, Belmonte M, Huang J, Belmonte A, Inoue S, Velasco R, Hickey B, Teneza-Mora N, Lumsden J, Reyes S, Banania JG, Reyes A, Guzman I, Richie TL, Epstein JE, Villasante E. IMRAS-Immunization with radiation-attenuated Plasmodium falciparum sporozoites by mosquito bite: Cellular immunity to sporozoites, CSP, AMA1, TRAP and CelTOS. PLoS One 2021; 16:e0256396. [PMID: 34415964 PMCID: PMC8378721 DOI: 10.1371/journal.pone.0256396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/21/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Immunization with radiation-attenuated sporozoites (RAS) by mosquito bites provides >90% sterile protection against Plasmodium falciparum malaria in humans. We conducted a clinical trial based on data from previous RAS clinical trials that suggested that 800-1200 infected bites should induce ~50% protective vaccine efficacy (VE) against controlled human malaria infection (CHMI) administered three weeks after the final immunization. Two cohorts were immunized separately. VE was 55% in Cohort 1 but 90% in Cohort 2, the cohort that received a higher first dose and a reduced (fractional) fifth dose. Immune responses were better boosted by the fractional fifth dose in Cohort 2 and suggested the importance of the fractional fifth dose for increased protection in Cohort 2 responses. Three protected subjects were later boosted and were protected suggesting that protection could be extended to at least 67 weeks. METHODS The ex vivo FluoroSpot assay was used to measure peripheral IFN-γ, IL2, and IFN-γ+IL2 responses to PfNF54 sporozoites and malaria antigens CSP, AMA1, TRAP, and CelTOS using pools of synthetic overlapping 15mer peptides spanning each antigen. RESULTS There was no correlation between IFN-γ, IL2, and IFN-γ+IL2 responses to sporozoites and protection, but fold-increases between post-4th and post-5th responses greater than 1.0 occurred mostly in protected subjects. IFN-γ and IL2 responses to TRAP, CelTOS and CSP occurred only in protected subjects. Peripheral IFN-γ, IL2, and IFN-γ+IL2 responses were short-lived and low by 27 weeks post-CHMI but were restored by boosting. CONCLUSIONS These studies highlight the importance of vaccine dose and schedule for vaccine efficacy, and suggest that CSP, TRAP, AMA1 and CelTOS may be targets of protective immunity. The correlation between fold-increases in responses and protection should be explored in other vaccine trials. TRIAL REGISTRATION ClinicalTrials.gov NCT01994525.
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Affiliation(s)
- Martha Sedegah
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Michael R. Hollingdale
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Harini Ganeshan
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Maria Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Jun Huang
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Arnel Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Sandra Inoue
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Rachel Velasco
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Bradley Hickey
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Nimfa Teneza-Mora
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Joanne Lumsden
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Sharina Reyes
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Jo Glenna Banania
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Anatalio Reyes
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Ivelese Guzman
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation, Bethesda, Maryland, United States of America
| | - Thomas L. Richie
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Judith E. Epstein
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Eileen Villasante
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
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7
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Moita D, Nunes-Cabaço H, Mendes AM, Prudêncio M. A guide to investigating immune responses elicited by whole-sporozoite pre-erythrocytic vaccines against malaria. FEBS J 2021; 289:3335-3359. [PMID: 33993649 DOI: 10.1111/febs.16016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 03/19/2021] [Accepted: 05/12/2021] [Indexed: 11/28/2022]
Abstract
In the last few decades, considerable efforts have been made toward the development of efficient vaccines against malaria. Whole-sporozoite (Wsp) vaccines, which induce efficient immune responses against the pre-erythrocytic (PE) stages (sporozoites and liver forms) of Plasmodium parasites, the causative agents of malaria, are among the most promising immunization strategies tested until present. Several Wsp PE vaccination approaches are currently under evaluation in the clinic, including radiation- or genetically-attenuated Plasmodium sporozoites, live parasites combined with chemoprophylaxis, or genetically modified rodent Plasmodium parasites. In addition to the assessment of their protective efficacy, clinical trials of Wsp PE vaccine candidates inevitably involve the thorough investigation of the immune responses elicited by vaccination, as well as the identification of correlates of protection. Here, we review the main methodologies employed to dissect the humoral and cellular immune responses observed in the context of Wsp PE vaccine clinical trials and discuss future strategies to further deepen the knowledge generated by these studies, providing a toolbox for the in-depth analysis of vaccine-induced immunogenicity.
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Affiliation(s)
- Diana Moita
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Helena Nunes-Cabaço
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - António M Mendes
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Miguel Prudêncio
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Portugal
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Tucker KD, Schanen BC, Phares TW, Sassano E, Terry FE, Hindocha P, Moise L, Kotraiah V, Martin WD, De Groot AS, Drake DR, Gutierrez GM, Noe AR. Identification, Selection and Immune Assessment of Liver Stage CD8 T Cell Epitopes From Plasmodium falciparum. Front Immunol 2021; 12:684116. [PMID: 34025684 PMCID: PMC8138313 DOI: 10.3389/fimmu.2021.684116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 04/13/2021] [Indexed: 11/13/2022] Open
Abstract
Immunization with radiation-attenuated sporozoites (RAS) has been shown to protect against malaria infection, primarily through CD8 T cell responses, but protection is limited based on parasite strain. Therefore, while CD8 T cells are an ideal effector population target for liver stage malaria vaccine development strategies, such strategies must incorporate conserved epitopes that cover a large range of class I human leukocyte antigen (HLA) supertypes to elicit cross-strain immunity across the target population. This approach requires identifying and characterizing a wide range of CD8 T cell epitopes for incorporation into a vaccine such that coverage across a large range of class I HLA alleles is attained. Accordingly, we devised an experimental framework to identify CD8 T cell epitopes from novel and minimally characterized antigens found at the pre-erythrocytic stage of parasite development. Through in silico analysis we selected conserved P. falciparum proteins, using P. vivax orthologues to establish stringent conservation parameters, predicted to have a high number of T cell epitopes across a set of six class I HLA alleles representative of major supertypes. Using the decision framework, five proteins were selected based on the density and number of predicted epitopes. Selected epitopes were synthesized as peptides and evaluated for binding to the class I HLA alleles in vitro to verify in silico binding predictions, and subsequently for stimulation of human T cells using the Modular IMmune In-vitro Construct (MIMIC®) technology to verify immunogenicity. By combining the in silico tools with the ex vivo high throughput MIMIC platform, we identified 15 novel CD8 T cell epitopes capable of stimulating an immune response in alleles across the class I HLA panel. We recommend these epitopes should be evaluated in appropriate in vivo humanized immune system models to determine their protective efficacy for potential inclusion in future vaccines.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Anne S. De Groot
- EpiVax Inc., Providence, RI, United States
- University of Georgia Center for Vaccines and Immunology, Athens, GA, United States
| | | | | | - Amy R. Noe
- Leidos Life Sciences, Leidos Inc., Frederick, MD, United States
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9
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Kanoi BN, Nagaoka H, Morita M, Tsuboi T, Takashima E. Leveraging the wheat germ cell-free protein synthesis system to accelerate malaria vaccine development. Parasitol Int 2020; 80:102224. [PMID: 33137499 DOI: 10.1016/j.parint.2020.102224] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/04/2020] [Accepted: 09/16/2020] [Indexed: 01/29/2023]
Abstract
Vaccines against infectious diseases have had great successes in the history of public health. Major breakthroughs have occurred in the development of vaccine-based interventions against viral and bacterial pathogens through the application of classical vaccine design strategies. In contrast the development of a malaria vaccine has been slow. Plasmodium falciparum malaria affects millions of people with nearly half of the world population at risk of infection. Decades of dedicated research has taught us that developing an effective vaccine will be time consuming, challenging, and expensive. Nevertheless, recent advancements such as the optimization of robust protein synthesis platforms, high-throughput immunoscreening approaches, reverse vaccinology, structural design of immunogens, lymphocyte repertoire sequencing, and the utilization of artificial intelligence, have renewed the prospects of an accelerated discovery of the key antigens in malaria. A deeper understanding of the major factors underlying the immunological and molecular mechanisms of malaria might provide a comprehensive approach to identifying novel and highly efficacious vaccines. In this review we discuss progress in novel antigen discoveries that leverage on the wheat germ cell-free protein synthesis system (WGCFS) to accelerate malaria vaccine development.
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Affiliation(s)
- Bernard N Kanoi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.
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10
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Hickey B, Teneza-Mora N, Lumsden J, Reyes S, Sedegah M, Garver L, Hollingdale MR, Banania JG, Ganeshan H, Dowler M, Reyes A, Tamminga C, Singer A, Simmons A, Belmonte M, Belmonte A, Huang J, Inoue S, Velasco R, Abot S, Vasquez CS, Guzman I, Wong M, Twomey P, Wojnarski M, Moon J, Alcorta Y, Maiolatesi S, Spring M, Davidson S, Chaudhury S, Villasante E, Richie TL, Epstein JE. IMRAS-A clinical trial of mosquito-bite immunization with live, radiation-attenuated P. falciparum sporozoites: Impact of immunization parameters on protective efficacy and generation of a repository of immunologic reagents. PLoS One 2020; 15:e0233840. [PMID: 32555601 PMCID: PMC7299375 DOI: 10.1371/journal.pone.0233840] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 05/12/2020] [Indexed: 12/31/2022] Open
Abstract
Background Immunization with radiation-attenuated sporozoites (RAS) by mosquito bite provides >90% sterile protection against Plasmodium falciparum (Pf) malaria in humans. RAS invade hepatocytes but do not replicate. CD8+ T cells recognizing parasite-derived peptides on the surface of infected hepatocytes are likely the primary protective mechanism. We conducted a randomized clinical trial of RAS immunization to assess safety, to achieve 50% vaccine efficacy (VE) against controlled human malaria infection (CHMI), and to generate reagents from protected and non-protected subjects for future identification of protective immune mechanisms and antigens. Methods Two cohorts (Cohort 1 and Cohort 2) of healthy, malaria-naïve, non-pregnant adults age 18–50 received five monthly immunizations with infected (true-immunized, n = 21) or non-infected (mock-immunized, n = 5) mosquito bites and underwent homologous CHMI at 3 weeks. Immunization parameters were selected for 50% protection based on prior clinical data. Leukapheresis was done to collect plasma and peripheral blood mononuclear cells. Results Adverse event rates were similar in true- and mock-immunized subjects. Two true- and two mock-immunized subjects developed large local reactions likely caused by mosquito salivary gland antigens. In Cohort 1, 11 subjects received 810–1235 infected bites; 6/11 (55%) were protected against CHMI vs. 0/3 mock-immunized and 0/6 infectivity controls (VE 55%). In Cohort 2, 10 subjects received 839–1131 infected bites with a higher first dose and a reduced fifth dose; 9/10 (90%) were protected vs. 0/2 mock-immunized and 0/6 controls (VE 90%). Three/3 (100%) protected subjects administered three booster immunizations were protected against repeat CHMI vs. 0/6 controls (VE 100%). Cohort 2 uniquely showed a significant rise in IFN-γ responses after the third and fifth immunizations and higher antibody responses to CSP. Conclusions PfRAS were generally safe and well tolerated. Cohort 2 had a higher first dose, reduced final dose, higher antibody responses to CSP and significant rise of IFN-γ responses after the third and fifth immunizations. Whether any of these factors contributed to increased protection in Cohort 2 requires further investigation. A cryobank of sera and cells from protected and non-protected individuals was generated for future immunological studies and antigen discovery. Trial registration ClinicalTrials.gov NCT01994525.
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Affiliation(s)
- Bradley Hickey
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Nimfa Teneza-Mora
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Joanne Lumsden
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Sharina Reyes
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Martha Sedegah
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Lindsey Garver
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Michael R. Hollingdale
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
- * E-mail:
| | - Jo Glenna Banania
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Harini Ganeshan
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Megan Dowler
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Anatalio Reyes
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Cindy Tamminga
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Alexandra Singer
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Alicia Simmons
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Maria Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Arnel Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Jun Huang
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Sandra Inoue
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Rachel Velasco
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Steve Abot
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Carlos S. Vasquez
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Ivelese Guzman
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Mimi Wong
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Patrick Twomey
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Mariusz Wojnarski
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - James Moon
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Yolanda Alcorta
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Santina Maiolatesi
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
| | - Michele Spring
- Henry M. Jackson Foundation, Bethesda, MD, United States of America
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Silas Davidson
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
| | - Sidhartha Chaudhury
- Walter Reed Army Institute of Research, Silver Spring, MD, United States of America
- Biotechnology HPC Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Frederick, MD, United States of America
| | - Eileen Villasante
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Thomas L. Richie
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Judith E. Epstein
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, United States of America
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11
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Smith EC, Limbach KJ, Rangel N, Oda K, Bolton JS, Du M, Gowda K, Wang J, Moch JK, Sonawane S, Velasco R, Belmonte A, Danner R, Lumsden JM, Patterson NB, Sedegah M, Hollingdale MR, Richie TL, Sacci JB, Villasante ED, Aguiar JC. Novel malaria antigen Plasmodium yoelii E140 induces antibody-mediated sterile protection in mice against malaria challenge. PLoS One 2020; 15:e0232234. [PMID: 32407410 PMCID: PMC7224506 DOI: 10.1371/journal.pone.0232234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 04/09/2020] [Indexed: 11/18/2022] Open
Abstract
Only a small fraction of the antigens expressed by malaria parasites have been evaluated as vaccine candidates. A successful malaria subunit vaccine will likely require multiple antigenic targets to achieve broad protection with high protective efficacy. Here we describe protective efficacy of a novel antigen, Plasmodium yoelii (Py) E140 (PyE140), evaluated against P. yoelii challenge of mice. Vaccines targeting PyE140 reproducibly induced up to 100% sterile protection in both inbred and outbred murine challenge models. Although PyE140 immunization induced high frequency and multifunctional CD8+ T cell responses, as well as CD4+ T cell responses, protection was mediated by PyE140 antibodies acting against blood stage parasites. Protection in mice was long-lasting with up to 100% sterile protection at twelve weeks post-immunization and durable high titer anti-PyE140 antibodies. The E140 antigen is expressed in all Plasmodium species, is highly conserved in both P. falciparum lab-adapted strains and endemic circulating parasites, and is thus a promising lead vaccine candidate for future evaluation against human malaria parasite species.
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Affiliation(s)
- Emily C. Smith
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Keith J. Limbach
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Nonenipha Rangel
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- CAMRIS International, Bethesda, Maryland, United States of America
| | - Kyosuke Oda
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- CAMRIS International, Bethesda, Maryland, United States of America
| | - Jessica S. Bolton
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Mengyan Du
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Kalpana Gowda
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Jianyang Wang
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- CAMRIS International, Bethesda, Maryland, United States of America
| | - J. Kathleen Moch
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Sharvari Sonawane
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Rachel Velasco
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Arnel Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Rebecca Danner
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Joanne M. Lumsden
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Noelle B. Patterson
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Martha Sedegah
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Michael R. Hollingdale
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, Maryland, United States of America
| | - Thomas L. Richie
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - John B. Sacci
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Eileen D. Villasante
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Joao C. Aguiar
- Malaria Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- CAMRIS International, Bethesda, Maryland, United States of America
- * E-mail:
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12
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Sorgi S, Bonezi V, Dominguez MR, Gimenez AM, Dobrescu I, Boscardin S, Nakaya HI, Bargieri DY, Soares IS, Silveira ELV. São Paulo School of Advanced Sciences on Vaccines: an overview. J Venom Anim Toxins Incl Trop Dis 2020; 26:e20190061. [PMID: 32362926 PMCID: PMC7187638 DOI: 10.1590/1678-9199-jvatitd-2019-0061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 02/21/2020] [Indexed: 01/08/2023] Open
Abstract
Two years ago, we held an exciting event entitled the São Paulo School of Advanced Sciences on Vaccines (SPSASV). Sixty-eight Ph.D. students, postdoctoral fellows and independent researchers from 37 different countries met at the Mendes Plaza Hotel located in the city of Santos, SP - Brazil to discuss the challenges and the new frontiers of vaccinology. The SPSASV provided a critical and comprehensive view of vaccine research from basics to the current state-of-the-art techniques performed worldwide. For 10 days, we discussed all the aspects of vaccine development in 36 lectures, 53 oral presentations and 2 poster sessions. At the end of the course, participants were further encouraged to present a model of a grant proposal related to vaccine development against individual pathogens. Among the targeted pathogens were viruses (Chikungunya, HIV, RSV, and Influenza), bacteria (Mycobacterium tuberculosis and Streptococcus pyogenes), parasites (Plasmodium falciparum or Plasmodium vivax), and the worm Strongyloides stercoralis. This report highlights some of the knowledge shared at the SPSASV.
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Affiliation(s)
- Sara Sorgi
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
- Dipartimento di Biotecnologie Mediche, Universita’ degli Studi di Siena, Siena, Italia
| | - Vivian Bonezi
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Mariana R. Dominguez
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Alba Marina Gimenez
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Irina Dobrescu
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Silvia Boscardin
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Helder I. Nakaya
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Daniel Y. Bargieri
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Irene S. Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Eduardo L. V. Silveira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
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13
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Bettencourt P. Current Challenges in the Identification of Pre-Erythrocytic Malaria Vaccine Candidate Antigens. Front Immunol 2020; 11:190. [PMID: 32153565 PMCID: PMC7046804 DOI: 10.3389/fimmu.2020.00190] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/24/2020] [Indexed: 12/27/2022] Open
Abstract
Plasmodium spp.-infected mosquitos inject sporozoites into the skin of a mammalian host during a blood meal. These enter the host's circulatory system and establish an infection in the liver. After a silent metamorphosis, merozoites invade the blood leading to the symptomatic and transmissible stages of malaria. The silent pre-erythrocytic malaria stage represents a bottleneck in the disease which is ideal to block progression to clinical malaria, through chemotherapeutic and immunoprophylactic interventions. RTS,S/AS01, the only malaria vaccine close to licensure, although with poor efficacy, blocks the sporozoite invasion mainly through the action of antibodies against the CSP protein, a major component of the pellicle of the sporozoite. Strikingly, sterile protection against malaria can be obtained through immunization with radiation-attenuated sporozoites, genetically attenuated sporozoites or through chemoprophylaxis with infectious sporozoites in animals and humans, but the deployability of sporozoite-based live vaccines pose tremendous challenges. The protection induced by sporozoites occurs in the pre-erythrocytic stages and is mediated mainly by antibodies against the sporozoite and CD8+ T cells against peptides presented by MHC class I molecules in infected hepatocytes. Thus, the identification of malaria antigens expressed in the sporozoite and liver-stage may provide new vaccine candidates to be included, alone or in combination, as recombinant protein-based, virus-like particles or sub-unit virally-vectored vaccines. Here I review the efforts being made to identify Plasmodium falciparum antigens expressed during liver-stage with focus on the development of parasite, hepatocyte, mouse models, and resulting rate of infection in order to identify new vaccine candidates and to improve the efficacy of the current vaccines. Finally, I propose new approaches for the identification of liver-stage antigens based on immunopeptidomics.
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14
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Antigenicity and immune correlate assessment of seven Plasmodium falciparum antigens in a longitudinal infant cohort from northern Ghana. Sci Rep 2019; 9:8621. [PMID: 31197225 PMCID: PMC6565625 DOI: 10.1038/s41598-019-45092-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/30/2019] [Indexed: 11/23/2022] Open
Abstract
The current global malaria control and elimination agenda requires development of additional effective disease intervention tools. Discovery and characterization of relevant parasite antigens is important for the development of new diagnostics and transmission monitoring tools and for subunit vaccine development. This study assessed the natural antibody response profile of seven novel Plasmodium falciparum pre-erythrocytic antigens and their potential association with protection against clinical malaria. Antigen-specific antibody levels in plasma collected at six time points from a longitudinal cohort of one-to-five year old children resident in a seasonal malaria transmission area of northern Ghana were assessed by ELISA. Antibody levels were compared between parasite-positive and parasite-negative individuals and the association of antibody levels with malaria risk assessed using a regression model. Plasma antibody levels against five of the seven antigens were significantly higher in parasite-positive children compared to parasite-negative children, especially during low transmission periods. None of the antigen-specific antibodies showed an association with protection against clinical malaria. The study identified five of the seven antigens as markers of exposure to malaria, and these will have relevance for the development of disease diagnostic and monitoring tools. The vaccine potential of these antigens requires further assessment.
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15
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Combining Monophosphoryl Lipid A (MPL), CpG Oligodeoxynucleotide (ODN), and QS-21 Adjuvants Induces Strong and Persistent Functional Antibodies and T Cell Responses against Cell-Traversal Protein for Ookinetes and Sporozoites (CelTOS) of Plasmodium falciparum in BALB/c Mice. Infect Immun 2019; 87:IAI.00911-18. [PMID: 30936155 DOI: 10.1128/iai.00911-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 03/17/2019] [Indexed: 12/22/2022] Open
Abstract
Plasmodium falciparum cell-traversal protein for ookinetes and sporozoites (PfCelTOS) is an advanced vaccine candidate that has a crucial role in the traversal of the malaria parasite in both mosquito and mammalian hosts. As recombinant purified proteins are normally poor immunogens, they require to be admixed with an adjuvant(s); therefore, the objective of the present study was to evaluate the capacity of different vaccine adjuvants, monophosphoryl lipid A (MPL), CpG, and Quillaja saponaria Molina fraction 21 (QS-21), alone or in combination (MCQ [MPL/CpG/QS-21]), to enhance the immunogenicity of Escherichia coli-expressed PfCelTOS in BALB/c mice. This goal was achieved by the assessment of anti-PfCelTOS IgG antibodies (level, titer, IgG isotype profile, avidity, and persistence) and extracellular Th1 cytokines using an enzyme-linked immunosorbent assay (ELISA) on postimmunized BALB/c mouse sera and PfCelTOS-stimulated splenocytes, respectively. Also, an assessment of the transmission-reducing activity (TRA) of anti-PfCelTOS obtained from different vaccine groups was carried out in female Anopheles stephensi mosquitoes by using a standard membrane feeding assay (SMFA). In comparison to PfCelTOS alone, administration of PfCelTOS with three distinct potent Th1 adjuvants in vaccine mouse groups showed enhancement and improvement of PfCelTOS immunogenicity that generated more bias toward a Th1 response with significantly enhanced titers and avidity of the anti-PfCelTOS responses that could impair ookinete development in A. stephensi However, immunization of mice with PfCelTOS with MCQ mixture adjuvants resulted in the highest levels of induction of antibody titers, avidity, and inhibitory antibodies in oocyst development (88%/26.7% reductions in intensity/prevalence) in A. stephensi It could be suggested that adjuvant combinations with different mechanisms stimulate better functional antibody responses than adjuvants individually against challenging diseases such as malaria.
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16
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Pirahmadi S, Zakeri S, A Mehrizi A, D Djadid N, Raz AA, J Sani J, Abbasi R, Ghorbanzadeh Z. Cell-traversal protein for ookinetes and sporozoites (CelTOS) formulated with potent TLR adjuvants induces high-affinity antibodies that inhibit Plasmodium falciparum infection in Anopheles stephensi. Malar J 2019; 18:146. [PMID: 31014347 PMCID: PMC6480871 DOI: 10.1186/s12936-019-2773-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/11/2019] [Indexed: 02/02/2023] Open
Abstract
Background Plasmodium falciparum parasite is the most deadly species of human malaria, and the development of an effective vaccine that prevents P. falciparum infection and transmission is a key target for malarial elimination and eradication programmes. P. falciparum cell-traversal protein for ookinetes and sporozoites (PfCelTOS) is an advanced vaccine candidate. A comparative study was performed to characterize the immune responses in BALB/c mouse immunized with Escherichia coli-expressed recombinant PfCelTOS (rPfCelTOS) in toll-like receptor (TLR)-based adjuvants, CpG and Poly I:C alone or in combination (CpG + Poly I:C), followed by the assessment of transmission-reducing activity (TRA) of anti-rPfCelTOS antibodies obtained from different vaccine groups in Anopheles stephensi. Methods The aim of the current work was achieved by head-to-head comparison of the vaccine groups using conventional and avidity enzyme-linked immunosorbent assay (ELISA), immunofluorescence test (IFAT), and standard membrane feeding assay (SMFA). Results Comparing to rPfCelTOS alone, administration of rPfCelTOS with two distinct TLR-based adjuvants in vaccine mouse groups showed a significant increase in responses (antibody level, IgG subclass analysis, avidity, and Th1 cytokines) and was able to induce reasonable transmission-reducing activity. Also, comparable functional activity of anti-rPfCelTOS antibodies was found in group that received antigen in either CpG or Poly I:C (69.9%/20% and 73.5%/24.4%, respectively, reductions in intensity/prevalence). However, the vaccine group receiving rPfCelTOS in combination with CpG + Poly I:C showed a significant induction in antibody titers and inhibitory antibodies in oocysts development (78.3%/19.6% reductions in intensity/prevalence) in An. stephensi. Conclusions A key finding in this investigation is that rPfCelTOS administered alone in BALB/c mouse is poorly immunogenic, with relatively low IgG level, avidity, inhibitory antibodies, and mixed Th1/Th2 responses. However, immunological characteristic (IgG level, cytophilic IgG2a and IgG2b, avidity, and Th1 cytokines) and TRA of anti-rPfCelTOS significantly enhanced in the presence of co-administration of TLR-based adjuvants, confirming that targeting TLRs would be an effective means for the enhancement of inducing TRA against rPfCelTOS. Electronic supplementary material The online version of this article (10.1186/s12936-019-2773-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sakineh Pirahmadi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran.
| | - Akram A Mehrizi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Navid D Djadid
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Abbas-Ali Raz
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Jafar J Sani
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Ronak Abbasi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Zahra Ghorbanzadeh
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
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17
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Pirahmadi S, Zakeri S, Mehrizi AA, Karimi L, Djadid ND. Heterogeneity in the acquisition of naturally acquired antibodies to cell-traversal protein for ookinetes and sporozoites (CelTOS) and thrombospondin-related adhesion protein (TRAP) of Plasmodium falciparum in naturally infected patients from unstable malaria areas in Iran. Acta Trop 2019; 190:365-374. [PMID: 30543766 DOI: 10.1016/j.actatropica.2018.12.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 12/07/2018] [Accepted: 12/08/2018] [Indexed: 11/19/2022]
Abstract
Currently, there is no subunit malaria vaccine capable of providing long-lasting protection, and a vaccine based on a single-antigen has shown moderate to unsatisfactory efficacies in clinical trials. As in malaria elimination and eradication strategies, the primary objective is reduction in disease and death due to P. falciparum, in the present investigation, for the first time, we attempted to determine and compare the naturally acquired immune responses to two well-recognized sporozoite antigens, cell-traversal protein for ookinetes and sporozoites (CelTOS) and thrombospondin-related adhesion protein (TRAP), in P. falciparum-infected individuals (n = 204) in low malaria transmission settings of Iran using ELISA. Besides, the profile of IgG isotype responses, the avidity of IgG, IgG1, and IgG3, and the association of anti-PfCelTOS and -PfTRAP antibodies with host age were evaluated. Positive antibody responses to PfCelTOS and PfTRAP antigens were detected in 16.2% and 31.9% of Iranian P. falciparum-infected individuals, respectively, indicating significantly lower immune response to PfCelTOS than PfTRAP (P <0.0001, McNemar's test). Also, among the positive samples for anti-PfCelTOS (n = 33) and -PfTRAP (n = 65) total IgG, the cytophilic IgG1 and IgG3 antibodies were predominant. A significant proportion of the examined positive responders had high- and intermediate-avidity for IgG (93.9%, 87.7%), IgG1 (96.3%, 87.7%), and IgG3 (76%, 78.7%) antibodies to both PfCelTOS and PfTRAP antigens, respectively, with no correlation with age (P >0.05; Spearman's correlation test). In conclusion, the present data suggests the acquisition of heterogenic immune responses to both antigens in the same patients naturally infected with P. falciparum from settings of low malaria transmission intensity in Iran in which their role in protection to malaria needs further study.
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Affiliation(s)
- Sakineh Pirahmadi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran.
| | - Akram Abouie Mehrizi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Leila Karimi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Navid Dinparast Djadid
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
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Hansen SG, Womack J, Scholz I, Renner A, Edgel KA, Xu G, Ford JC, Grey M, St Laurent B, Turner JM, Planer S, Legasse AW, Richie TL, Aguiar JC, Axthelm MK, Villasante ED, Weiss W, Edlefsen PT, Picker LJ, Früh K. Cytomegalovirus vectors expressing Plasmodium knowlesi antigens induce immune responses that delay parasitemia upon sporozoite challenge. PLoS One 2019; 14:e0210252. [PMID: 30673723 PMCID: PMC6343944 DOI: 10.1371/journal.pone.0210252] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 12/19/2018] [Indexed: 12/12/2022] Open
Abstract
The development of a sterilizing vaccine against malaria remains one of the highest priorities for global health research. While sporozoite vaccines targeting the pre-erythrocytic stage show great promise, it has not been possible to maintain efficacy long-term, likely due to an inability of these vaccines to maintain effector memory T cell responses in the liver. Vaccines based on human cytomegalovirus (HCMV) might overcome this limitation since vectors based on rhesus CMV (RhCMV), the homologous virus in rhesus macaques (RM), elicit and indefinitely maintain high frequency, non-exhausted effector memory T cells in extralymphoid tissues, including the liver. Moreover, RhCMV strain 68-1 elicits CD8+ T cells broadly recognizing unconventional epitopes exclusively restricted by MHC-II and MHC-E. To evaluate the potential of these unique immune responses to protect against malaria, we expressed four Plasmodium knowlesi (Pk) antigens (CSP, AMA1, SSP2/TRAP, MSP1c) in RhCMV 68-1 or in Rh189-deleted 68-1, which additionally elicits canonical MHC-Ia-restricted CD8+ T cells. Upon inoculation of RM with either of these Pk Ag expressing RhCMV vaccines, we obtained T cell responses to each of the four Pk antigens. Upon challenge with Pk sporozoites we observed a delayed appearance of blood stage parasites in vaccinated RM consistent with a 75-80% reduction of parasite release from the liver. Moreover, the Rh189-deleted RhCMV/Pk vectors elicited sterile protection in one RM. Once in the blood, parasite growth was not affected. In contrast to T cell responses induced by Pk infection, RhCMV vectors maintained sustained T cell responses to all four malaria antigens in the liver post-challenge. The delayed appearance of blood stage parasites is thus likely due to a T cell-mediated inhibition of liver stage parasite development. As such, this vaccine approach can be used to efficiently test new T cell antigens, improve current vaccines targeting the liver stage and complement vaccines targeting erythrocytic antigens.
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Affiliation(s)
- Scott G Hansen
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Jennie Womack
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
| | - Isabel Scholz
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
| | - Andrea Renner
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Kimberly A Edgel
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Guangwu Xu
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
| | - Julia C Ford
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
| | - Mikayla Grey
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
| | - Brandyce St Laurent
- National Institutes of Health, Laboratory of Malaria and Vector Research, Malaria Pathogenesis and Human Immunity Unit, Rockville, MD, United States of America
| | - John M Turner
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Shannon Planer
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Al W Legasse
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Thomas L Richie
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Joao C Aguiar
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Michael K Axthelm
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Eileen D Villasante
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Walter Weiss
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Paul T Edlefsen
- Statistical Center for HIV/AIDS Research and Prevention, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States of America
| | - Louis J Picker
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Klaus Früh
- Oregon Health & Science University, Vaccine & Gene Therapy Institute, Beaverton, OR, United States of America
- Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, United States of America
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19
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Plasmodium genomics: an approach for learning about and ending human malaria. Parasitol Res 2018; 118:1-27. [PMID: 30402656 DOI: 10.1007/s00436-018-6127-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/19/2018] [Indexed: 12/31/2022]
Abstract
Malaria causes high levels of morbidity and mortality in human beings worldwide. According to the World Health Organization (WHO), about half a million people die of this disease each year. Malaria is caused by six species of parasites belonging to the Plasmodium genus: P. falciparum, P. knowlesi, P. vivax, P. malariae, P. ovale curtisi, and P. ovale wallikeri. Currently, malaria is being kept under control with varying levels of elimination success in different countries. The development of new molecular tools as well as the use of next-generation sequencing (NGS) technologies and novel bioinformatic approaches has improved our knowledge of malarial epidemiology, diagnosis, treatment, vaccine development, and surveillance strategies. In this work, the genetics and genomics of human malarias have been analyzed. Since the first P. falciparum genome was sequenced in 2002, various population-level genetic and genomic surveys, together with transcriptomic and proteomic studies, have shown the importance of molecular approaches in supporting malaria elimination.
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20
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Steel RWJ, Pei Y, Camargo N, Kaushansky A, Dankwa DA, Martinson T, Nguyen T, Betz W, Cardamone H, Vigdorovich V, Dambrauskas N, Carbonetti S, Vaughan AM, Sather DN, Kappe SHI. Plasmodium yoelii S4/CelTOS is important for sporozoite gliding motility and cell traversal. Cell Microbiol 2018; 20. [PMID: 29253313 DOI: 10.1111/cmi.12817] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 12/01/2017] [Accepted: 12/13/2017] [Indexed: 01/02/2023]
Abstract
Gliding motility and cell traversal by the Plasmodium ookinete and sporozoite invasive stages allow penetration of cellular barriers to establish infection of the mosquito vector and mammalian host, respectively. Motility and traversal are not observed in red cell infectious merozoites, and we have previously classified genes that are expressed in sporozoites but not merozoites (S genes) in order to identify proteins involved in these processes. The S4 gene has been described as criticaly involved in Cell Traversal for Ookinetes and Sporozoites (CelTOS), yet knockout parasites (s4/celtos¯) do not generate robust salivary gland sporozoite numbers, precluding a thorough analysis of S4/CelTOS function during host infection. We show here that a failure of oocysts to develop or survive in the midgut contributes to the poor mosquito infection by Plasmodium yoelii (Py) s4/celtos¯ rodent malaria parasites. We rescued this phenotype by expressing S4/CelTOS under the ookinete-specific circumsporozoite protein and thrombospondin-related anonymous protein-related protein (CTRP) promoter (S4/CelTOSCTRP ), generating robust numbers of salivary gland sporozoites lacking S4/CelTOS that were suitable for phenotypic analysis. Py S4/CelTOSCTRP sporozoites showed reduced infectivity in BALB/c mice when compared to wild-type sporozoites, although they appeared more infectious than sporozoites deficient in the related traversal protein PLP1/SPECT2 (Py plp1/spect2¯). Using in vitro assays, we substantiate the role of S4/CelTOS in sporozoite cell traversal, but also uncover a previously unappreciated role for this protein for sporozoite gliding motility.
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Affiliation(s)
- Ryan W J Steel
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Ying Pei
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Nelly Camargo
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Alexis Kaushansky
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA.,Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Dorender A Dankwa
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Thomas Martinson
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Thao Nguyen
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Will Betz
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Hayley Cardamone
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Vladimir Vigdorovich
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Nicholas Dambrauskas
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Sara Carbonetti
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Ashley M Vaughan
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - D Noah Sather
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA
| | - Stefan H I Kappe
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington, USA.,Department of Global Health, University of Washington, Seattle, Washington, USA
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Abstract
Controlled human malaria infection (CHMI) entails deliberate infection with malaria parasites either by mosquito bite or by direct injection of sporozoites or parasitized erythrocytes. When required, the resulting blood-stage infection is curtailed by the administration of antimalarial drugs. Inducing a malaria infection via inoculation with infected blood was first used as a treatment (malariotherapy) for neurosyphilis in Europe and the United States in the early 1900s. More recently, CHMI has been applied to the fields of malaria vaccine and drug development, where it is used to evaluate products in well-controlled early-phase proof-of-concept clinical studies, thus facilitating progression of only the most promising candidates for further evaluation in areas where malaria is endemic. Controlled infections have also been used to immunize against malaria infection. Historically, CHMI studies have been restricted by the need for access to insectaries housing infected mosquitoes or suitable malaria-infected individuals. Evaluation of vaccine and drug candidates has been constrained in these studies by the availability of a limited number of Plasmodium falciparum isolates. Recent advances have included cryopreservation of sporozoites, the manufacture of well-characterized and genetically distinct cultured malaria cell banks for blood-stage infection, and the availability of Plasmodium vivax-specific reagents. These advances will help to accelerate malaria vaccine and drug development by making the reagents for CHMI more widely accessible and also enabling a more rigorous evaluation with multiple parasite strains and species. Here we discuss the different applications of CHMI, recent advances in the use of CHMI, and ongoing challenges for consideration.
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22
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Aguilar R, Casabonne D, O’Callaghan-Gordo C, Vidal M, Campo JJ, Mutalima N, Angov E, Dutta S, Gaur D, Chitnis CE, Chauhan V, Michel A, de Sanjosé S, Waterboer T, Kogevinas M, Newton R, Dobaño C. Assessment of the Combined Effect of Epstein-Barr Virus and Plasmodium falciparum Infections on Endemic Burkitt Lymphoma Using a Multiplex Serological Approach. Front Immunol 2017; 8:1284. [PMID: 29123514 PMCID: PMC5662586 DOI: 10.3389/fimmu.2017.01284] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022] Open
Abstract
Epstein-Barr virus (EBV) is a necessary cause of endemic Burkitt lymphoma (eBL), while the role of Plasmodium falciparum in eBL remains uncertain. This study aimed to generate new hypotheses on the interplay between both infections in the development of eBL by investigating the IgG and IgM profiles against several EBV and P. falciparum antigens. Serum samples collected in a childhood study in Malawi (2005-2006) from 442 HIV-seronegative children (271 eBL cases and 171 controls) between 1.4 and 15 years old were tested by quantitative suspension array technology against a newly developed multiplex panel combining 4 EBV antigens [Z Epstein-Barr replication activator protein (ZEBRA), early antigen-diffuse component (EA-D), EBV nuclear antigen 1, and viral capsid antigen p18 subunit (VCA-p18)] and 15 P. falciparum antigens selected for their immunogenicity, role in malaria pathogenesis, and presence in different parasite stages. Principal component analyses, multivariate logistic models, and elastic-net regressions were used. As expected, elevated levels of EBV IgG (especially against the lytic antigens ZEBRA, EA-D, and VCA-p18) were strongly associated with eBL [high vs low tertile odds ratio (OR) = 8.67, 95% confidence interval (CI) = 4.81-15.64]. Higher IgG responses to the merozoite surface protein 3 were observed in children with eBL compared with controls (OR = 1.29, 95% CI = 1.02-1.64), showing an additive interaction with EBV IgGs (OR = 10.6, 95% CI = 5.1-22.2, P = 0.05). Using elastic-net regression models, eBL serological profile was further characterized by lower IgM levels against P. falciparum preerythrocytic-stage antigen CelTOS and EBV lytic antigen VCA-p18 compared with controls. In a secondary analysis, abdominal Burkitt lymphoma had lower IgM to EBV and higher IgG to EA-D levels than cases with head involvement. Overall, this exploratory study confirmed the strong role of EBV in eBL and identified differential IgG and IgM patterns to erythrocytic vs preerythrocytic P. falciparum antigens that suggest a more persistent/chronic malaria exposure and a weaker IgM immune response in children with eBL compared with controls. Future studies should continue exploring how the malaria infection status and the immune response to P. falciparum interact with EBV infection in the development of eBL.
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Affiliation(s)
- Ruth Aguilar
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Delphine Casabonne
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Unit of Infections and Cancer, Cancer Epidemiology Research Programme, IDIBELL, Institut Català d’Oncologia, L’Hospitalet de Llobregat, Spain
| | - Cristina O’Callaghan-Gordo
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Marta Vidal
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Joseph J. Campo
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Nora Mutalima
- Department of Orthopaedic Surgery, Monash Health, Melbourne, VIC, Australia
- Department of Surgery, School of Clinical Sciences, Monash University, Melbourne, VIC, Australia
| | | | | | - Deepak Gaur
- ICGEB, Delhi, India
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | | | | | | | - Silvia de Sanjosé
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Unit of Infections and Cancer, Cancer Epidemiology Research Programme, IDIBELL, Institut Català d’Oncologia, L’Hospitalet de Llobregat, Spain
| | - Tim Waterboer
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Manolis Kogevinas
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - Rob Newton
- Epidemiology and Cancer Statistics Group, University of York, York, United Kingdom
- MRC/UVRI Uganda Research Unit on AIDS, Entebbe, Uganda
| | - Carlota Dobaño
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
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Bruder JT, Chen P, Ekberg G, Smith EC, Lazarski CA, Myers BA, Bolton J, Sedegah M, Villasante E, Richie TL, King CR, Aguiar JC, Doolan DL, Brough DE. Profiling the Targets of Protective CD8 + T Cell Responses to Infection. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2017; 7:20-31. [PMID: 28948187 PMCID: PMC5602877 DOI: 10.1016/j.omtm.2017.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 08/14/2017] [Indexed: 11/22/2022]
Abstract
T cells are critical effectors of host immunity that target intracellular pathogens, such as the causative agents of HIV, tuberculosis, and malaria. The development of vaccines that induce effective cell-mediated immunity against such pathogens has proved challenging; for tuberculosis and malaria, many of the antigens targeted by protective T cells are not known. Here, we report a novel approach for screening large numbers of antigens as potential targets of T cells. Malaria provides an excellent model to test this antigen discovery platform because T cells are critical mediators of protection following immunization with live sporozoite vaccines and the specific antigen targets are unknown. We generated an adenovirus array by cloning 312 highly expressed pre-erythrocytic Plasmodium yoelii antigens into adenovirus vectors using high-throughput methodologies. The array was screened to identify antigen-specific CD8+ T cells induced by a live sporozoite vaccine regimen known to provide high levels of sterile protection mediated by CD8+ T cells. We identified 69 antigens that were targeted by CD8+ T cells induced by this vaccine regimen. The antigen that recalled the highest frequency of CD8+ T cells, PY02605, induced protective responses in mice, demonstrating proof of principle for this approach in identifying antigens for vaccine development.
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Affiliation(s)
- Joseph T. Bruder
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
- Corresponding author: Joseph T. Bruder, Summit Consulting, 567 Chestertown Street, Gaithersburg, MD 20878, USA.
| | - Ping Chen
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
| | - Greg Ekberg
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
| | - Emily C. Smith
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., 6720A Rockledge Drive, Suite 100, Bethesda, MD 20817, USA
| | | | - Bennett A. Myers
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
| | - Jessica Bolton
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., 6720A Rockledge Drive, Suite 100, Bethesda, MD 20817, USA
| | - Martha Sedegah
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Eileen Villasante
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Thomas L. Richie
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - C. Richter King
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
| | - Joao C. Aguiar
- Malaria Department, Naval Medical Research Center (NMRC), 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
- Camris International, 3 Bethesda Metro Center, 16th Floor, Bethesda, MD 20814, USA
| | - Denise L. Doolan
- Australian Institute of Tropical Health and Medicine, James Cook University, McGregor Road, Cairns, QLD 4870, Australia
| | - Douglas E. Brough
- GenVec, Inc., 910 Clopper Road, Suite 220N, Gaithersburg, MD 20878, USA
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Sack B, Kappe SHI, Sather DN. Towards functional antibody-based vaccines to prevent pre-erythrocytic malaria infection. Expert Rev Vaccines 2017; 16:403-414. [PMID: 28277097 DOI: 10.1080/14760584.2017.1295853] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION An effective malaria vaccine would be considered a milestone of modern medicine, yet has so far eluded research and development efforts. This can be attributed to the extreme complexity of the malaria parasites, presenting with a multi-stage life cycle, high genome complexity and the parasite's sophisticated immune evasion measures, particularly antigenic variation during pathogenic blood stage infection. However, the pre-erythrocytic (PE) early infection forms of the parasite exhibit relatively invariant proteomes, and are attractive vaccine targets as they offer multiple points of immune system attack. Areas covered: We cover the current state of and roadblocks to the development of an effective, antibody-based PE vaccine, including current vaccine candidates, limited biological knowledge, genetic heterogeneity, parasite complexity, and suboptimal preclinical models as well as the power of early stage clinical models. Expert commentary: PE vaccines will need to elicit broad and durable immunity to prevent infection. This could be achievable if recent innovations in studying the parasites' infection biology, rational vaccine selection and design as well as adjuvant formulation are combined in a synergistic and multipronged approach. Improved preclinical assays as well as the iterative testing of vaccine candidates in controlled human malaria infection trials will further accelerate this effort.
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Affiliation(s)
- Brandon Sack
- a Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute) , Seattle , WA , USA
| | - Stefan H I Kappe
- a Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute) , Seattle , WA , USA.,b Department of Global Health , University of Washington , Seattle , WA , USA
| | - D Noah Sather
- a Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute) , Seattle , WA , USA
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Assessment of the Plasmodium falciparum Preerythrocytic Antigen UIS3 as a Potential Candidate for a Malaria Vaccine. Infect Immun 2017; 85:IAI.00641-16. [PMID: 28031267 PMCID: PMC5328496 DOI: 10.1128/iai.00641-16] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 12/20/2016] [Indexed: 01/03/2023] Open
Abstract
Efforts are under way to improve the efficacy of subunit malaria vaccines through assessments of new adjuvants, vaccination platforms, and antigens. In this study, we further assessed the Plasmodium falciparum antigen upregulated in infective sporozoites 3 (PfUIS3) as a vaccine candidate. PfUIS3 was expressed in the viral vectors chimpanzee adenovirus 63 (ChAd63) and modified vaccinia virus Ankara (MVA) and used to immunize mice in a prime-boost regimen. We previously demonstrated that this regimen could provide partial protection against challenge with chimeric P. berghei parasites expressing PfUIS3. We now show that ChAd63-MVA PfUIS3 can also provide partial cross-species protection against challenge with wild-type P. berghei parasites. We also show that PfUIS3-specific cellular memory responses could be recalled in human volunteers exposed to P. falciparum parasites in a controlled human malaria infection study. When ChAd63-MVA PfUIS3 was coadministered with the vaccine candidate P. falciparum thrombospondin-related adhesion protein (PfTRAP) expressed in the ChAd63-MVA system, there was no significant change in immunogenicity to either vaccine. However, when mice were challenged with double chimeric P. berghei-P. falciparum parasites expressing both PfUIS3 and PfTRAP, vaccine efficacy was improved to 100% sterile protection. This synergistic effect was evident only when the two vaccines were mixed and administered at the same site. We have therefore demonstrated that vaccination with PfUIS3 can induce a consistent delay in patent parasitemia across mouse strains and against chimeric parasites expressing PfUIS3 as well as wild-type P. berghei; when this vaccine is combined with another partially protective regimen (ChAd63-MVA PfTRAP), complete protection is induced.
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Pichyangkul S, Spring MD, Yongvanitchit K, Kum-Arb U, Limsalakpetch A, Im-Erbsin R, Ubalee R, Vanachayangkul P, Remarque EJ, Angov E, Smith PL, Saunders DL. Chemoprophylaxis with sporozoite immunization in P. knowlesi rhesus monkeys confers protection and elicits sporozoite-specific memory T cells in the liver. PLoS One 2017; 12:e0171826. [PMID: 28182750 PMCID: PMC5300246 DOI: 10.1371/journal.pone.0171826] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/26/2017] [Indexed: 12/11/2022] Open
Abstract
Whole malaria sporozoite vaccine regimens are promising new strategies, and some candidates have demonstrated high rates of durable clinical protection associated with memory T cell responses. Little is known about the anatomical distribution of memory T cells following whole sporozoite vaccines, and immunization of nonhuman primates can be used as a relevant model for humans. We conducted a chemoprophylaxis with sporozoite (CPS) immunization in P. knowlesi rhesus monkeys and challenged via mosquito bites. Half of CPS immunized animals developed complete protection, with a marked delay in parasitemia demonstrated in the other half. Antibody responses to whole sporozoites, CSP, and AMA1, but not CelTOS were detected. Peripheral blood T cell responses to whole sporozoites, but not CSP and AMA1 peptides were observed. Unlike peripheral blood, there was a high frequency of sporozoite-specific memory T cells observed in the liver and bone marrow. Interestingly, sporozoite-specific CD4+ and CD8+ memory T cells in the liver highly expressed chemokine receptors CCR5 and CXCR6, both of which are known for liver sinusoid homing. The majority of liver sporozoite-specific memory T cells expressed CD69, a phenotypic marker of tissue-resident memory (TRM) cells, which are well positioned to rapidly control liver-stage infection. Vaccine strategies that aim to elicit large number of liver TRM cells may efficiently increase the efficacy and durability of response against pre-erythrocytic parasites.
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Affiliation(s)
- Sathit Pichyangkul
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
- * E-mail:
| | - Michele D. Spring
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Kosol Yongvanitchit
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Utaiwan Kum-Arb
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | | | - Rawiwan Im-Erbsin
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - Ratawan Ubalee
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | | | | | - Evelina Angov
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Philip L. Smith
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
| | - David L. Saunders
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand
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Kanoi BN, Takashima E, Morita M, White MT, Palacpac NMQ, Ntege EH, Balikagala B, Yeka A, Egwang TG, Horii T, Tsuboi T. Antibody profiles to wheat germ cell-free system synthesized Plasmodium falciparum proteins correlate with protection from symptomatic malaria in Uganda. Vaccine 2017; 35:873-881. [PMID: 28089547 DOI: 10.1016/j.vaccine.2017.01.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 12/20/2016] [Accepted: 01/04/2017] [Indexed: 12/19/2022]
Abstract
The key targets of protective antibodies against Plasmodium falciparum remain largely unknown. In this study, we determined immunoreactivity to 1827 recombinant proteins derived from 1565 genes representing ∼30% of the entire P. falciparum genome, for identification of novel malaria vaccine candidates. The recombinant proteins were expressed by wheat germ cell-free system, a platform that can synthesize quality plasmodial proteins that elicit biologically active antibodies in animals. Sera were obtained from indigenous residents of a malaria endemic region in Northern Uganda who were enrolled at the start of a rainy season and prospectively monitored for symptomatic malaria episodes for a year. Immunoreactivity to sera was determined by AlphaScreen; a homogeneous high-throughput system that detects protein interactions. Our analysis revealed antibody responses to 128 proteins that significantly associated with protection from symptomatic malaria. From 128 proteins, 53 were down-selected as the most plausible targets of host protective immune response by virtue of having a predicted signal peptide and/or transmembrane domain(s), or confirmed localization on the parasite surface. The 53 proteins comprised of not only previously characterized vaccine candidates but also uncharacterized proteins. Proteins involved in erythrocyte invasion; RON4, RON2 and CLAG3.1 and pre-erythrocytic proteins; SIAP-2, TRAP and CelTOS, were recommended for prioritization for further evaluation as vaccine candidates. The findings clearly demonstrate that generation of the protein library using the wheat germ cell-free system coupled with high throughput immunoscreening with AlphaScreen offers new options for rational discovery and selection of potential malaria vaccine candidates.
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Affiliation(s)
- Bernard N Kanoi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Michael T White
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia; MRC Center for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Nirianne M Q Palacpac
- Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Suita 565-0871, Japan
| | - Edward H Ntege
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Betty Balikagala
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Adoke Yeka
- Makerere University College of Health Sciences, School of Public Health, Kampala, Uganda
| | - Thomas G Egwang
- Med Biotech Laboratories, Plot 4-6 Bell Close, Port Bell Road Luzira, Kampala, Uganda
| | - Toshihiro Horii
- Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Suita 565-0871, Japan
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.
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Legastelois I, Buffin S, Peubez I, Mignon C, Sodoyer R, Werle B. Non-conventional expression systems for the production of vaccine proteins and immunotherapeutic molecules. Hum Vaccin Immunother 2016; 13:947-961. [PMID: 27905833 DOI: 10.1080/21645515.2016.1260795] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The increasing demand for recombinant vaccine antigens or immunotherapeutic molecules calls into question the universality of current protein expression systems. Vaccine production can require relatively low amounts of expressed materials, but represents an extremely diverse category consisting of different target antigens with marked structural differences. In contrast, monoclonal antibodies, by definition share key molecular characteristics and require a production system capable of very large outputs, which drives the quest for highly efficient and cost-effective systems. In discussing expression systems, the primary assumption is that a universal production platform for vaccines and immunotherapeutics will unlikely exist. This review provides an overview of the evolution of traditional expression systems, including mammalian cells, yeast and E.coli, but also alternative systems such as other bacteria than E. coli, transgenic animals, insect cells, plants and microalgae, Tetrahymena thermophila, Leishmania tarentolae, filamentous fungi, cell free systems, and the incorporation of non-natural amino acids.
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Affiliation(s)
| | - Sophie Buffin
- a Research and Development, Sanofi Pasteur , Marcy L'Etoile , France
| | - Isabelle Peubez
- a Research and Development, Sanofi Pasteur , Marcy L'Etoile , France
| | | | - Régis Sodoyer
- b Technology Research Institute Bioaster , Lyon , France
| | - Bettina Werle
- b Technology Research Institute Bioaster , Lyon , France
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Steel RW, Kappe SH, Sack BK. An expanding toolkit for preclinical pre-erythrocytic malaria vaccine development: bridging traditional mouse malaria models and human trials. Future Microbiol 2016; 11:1563-1579. [PMID: 27855488 DOI: 10.2217/fmb-2016-0077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Malaria remains a significant public health burden with 214 million new infections and over 400,000 deaths in 2015. Elucidating relevant Plasmodium parasite biology can lead to the identification of novel ways to control and ultimately eliminate the parasite within geographic areas. Particularly, the development of an effective vaccine that targets the clinically silent pre-erythrocytic stages of infection would significantly augment existing malaria elimination tools by preventing both the onset of blood-stage infection/disease as well as spread of the parasite through mosquito transmission. In this Perspective, we discuss the role of small animal models in pre-erythrocytic stage vaccine development, highlighting how human liver-chimeric and human immune system mice are emerging as valuable components of these efforts.
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Affiliation(s)
- Ryan Wj Steel
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Stefan Hi Kappe
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Brandon K Sack
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
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Arévalo-Herrera M, Vásquez-Jiménez JM, Lopez-Perez M, Vallejo AF, Amado-Garavito AB, Céspedes N, Castellanos A, Molina K, Trejos J, Oñate J, Epstein JE, Richie TL, Herrera S. Protective Efficacy of Plasmodium vivax Radiation-Attenuated Sporozoites in Colombian Volunteers: A Randomized Controlled Trial. PLoS Negl Trop Dis 2016; 10:e0005070. [PMID: 27760143 PMCID: PMC5070852 DOI: 10.1371/journal.pntd.0005070] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/24/2016] [Indexed: 11/23/2022] Open
Abstract
Background Immunizing human volunteers by mosquito bite with radiation-attenuated Plasmodium falciparum sporozoites (RAS) results in high-level protection against infection. Only two volunteers have been similarly immunized with P. vivax (Pv) RAS, and both were protected. A phase 2 controlled clinical trial was conducted to assess the safety and protective efficacy of PvRAS immunization. Methodology/Principal Findings A randomized, single-blinded trial was conducted. Duffy positive (Fy+; Pv susceptible) individuals were enrolled: 14 received bites from irradiated (150 ± 10 cGy) Pv-infected Anopheles mosquitoes (RAS) and 7 from non-irradiated non-infected mosquitoes (Ctl). An additional group of seven Fy- (Pv refractory) volunteers was immunized with bites from non-irradiated Pv-infected mosquitoes. A total of seven immunizations were carried out at mean intervals of nine weeks. Eight weeks after last immunization, a controlled human malaria infection (CHMI) with non-irradiated Pv-infected mosquitoes was performed. Nineteen volunteers completed seven immunizations (12 RAS, 2 Ctl, and 5 Fy-) and received a CHMI. Five of 12 (42%) RAS volunteers were protected (receiving a median of 434 infective bites) compared with 0/2 Ctl. None of the Fy- volunteers developed infection by the seventh immunization or after CHMI. All non-protected volunteers developed symptoms 8–13 days after CHMI with a mean pre-patent period of 12.8 days. No serious adverse events related to the immunizations were observed. Specific IgG1 anti-PvCS response was associated with protection. Conclusion Immunization with PvRAS was safe, immunogenic, and induced sterile immunity in 42% of the Fy+ volunteers. Moreover, Fy- volunteers were refractory to Pv malaria. Trial registration Identifier: NCT01082341. Despite the advances in Plasmodium falciparum (Pf) vaccine development, progress in developing P. vivax (Pv) vaccines lags far behind. Immunization via mosquito bites with Pf radiation-attenuated sporozoites (RAS) has been the gold standard model for induction of sterile protection against malaria infection and has allowed the study of the complex mechanisms of immunity. The first trials using PfRAS were performed in the late 1960’s, and thereafter greatly contributed to the development of vaccines against Pf. However, PvRAS immunization in humans has only been carried out in two volunteers since 1974. To our knowledge, this is the first clinical trial using significant numbers of volunteers for PvRAS immunization. Our findings confirm that immunization with PvRAS is safe, immunogenic and induces sterile immunity in 42% of the volunteers. It demonstrates that it is possible to induce sterile protection with PvRAS as seen with PfRAS and confirms that immunity against the PvCS protein (IgG1 levels) correlates with protection. Research findings and reagents generated in this study are expected to yield insights on key immune determinants of sterile protection against Pv, which may guide the development of a cost-effective vaccine against this parasite species.
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Affiliation(s)
- Myriam Arévalo-Herrera
- Malaria Vaccine and Drug Development Center (MVDC), Cali, Colombia
- Faculty of Health, Universidad del Valle, Cali, Colombia
- * E-mail:
| | | | - Mary Lopez-Perez
- Malaria Vaccine and Drug Development Center (MVDC), Cali, Colombia
| | | | | | - Nora Céspedes
- Malaria Vaccine and Drug Development Center (MVDC), Cali, Colombia
| | | | - Karen Molina
- Malaria Vaccine and Drug Development Center (MVDC), Cali, Colombia
| | | | | | - Judith E. Epstein
- Naval Medical Research Center, Malaria Department, Silver Spring, Maryland, United States of America
| | | | - Sócrates Herrera
- Malaria Vaccine and Drug Development Center (MVDC), Cali, Colombia
- Caucaseco Scientific Research Center, Cali, Colombia
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Hickey BW, Lumsden JM, Reyes S, Sedegah M, Hollingdale MR, Freilich DA, Luke TC, Charoenvit Y, Goh LM, Berzins MP, Bebris L, Sacci JB, De La Vega P, Wang R, Ganeshan H, Abot EN, Carucci DJ, Doolan DL, Brice GT, Kumar A, Aguiar J, Nutman TB, Leitman SF, Hoffman SL, Epstein JE, Richie TL. Mosquito bite immunization with radiation-attenuated Plasmodium falciparum sporozoites: safety, tolerability, protective efficacy and humoral immunogenicity. Malar J 2016; 15:377. [PMID: 27448805 PMCID: PMC4957371 DOI: 10.1186/s12936-016-1435-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 07/09/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In this phase 1 clinical trial, healthy adult, malaria-naïve subjects were immunized with radiation-attenuated Plasmodium falciparum sporozoites (PfRAS) by mosquito bite and then underwent controlled human malaria infection (CHMI). The PfRAS model for immunization against malaria had previously induced >90 % sterile protection against homologous CHMI. This study was to further explore the safety, tolerability and protective efficacy of the PfRAS model and to provide biological specimens to characterize protective immune responses and identify protective antigens in support of malaria vaccine development. METHODS Fifty-seven subjects were screened, 41 enrolled and 30 received at least one immunization. The true-immunized subjects received PfRAS via mosquito bite and the mock-immunized subjects received mosquito bites from irradiated uninfected mosquitoes. Sera and peripheral blood mononuclear cells (PBMCs) were collected before and after PfRAS immunizations. RESULTS Immunization with PfRAS was generally safe and well tolerated, and repeated immunization via mosquito bite did not appear to increase the risk or severity of AEs. Local adverse events (AEs) of true-immunized and mock-immunized groups consisted of erythaema, papules, swelling, and induration and were consistent with reactions from mosquito bites seen in nature. Two subjects, one true- and one mock-immunized, developed large local reactions that completely resolved, were likely a result of mosquito salivary antigens, and were withdrawn from further participation as a safety precaution. Systemic AEs were generally rare and mild, consisting of headache, myalgia, nausea, and low-grade fevers. Two true-immunized subjects experienced fever, malaise, myalgia, nausea, and rigours approximately 16 h after immunization. These symptoms likely resulted from pre-formed antibodies interacting with mosquito salivary antigens. Ten subjects immunized with PfRAS underwent CHMI and five subjects (50 %) were sterilely protected and there was a significant delay to parasitaemia in the other five subjects. All ten subjects developed humoral immune responses to whole sporozoites and to the circumsporozoite protein prior to CHMI, although the differences between protected and non-protected subjects were not statistically significant for this small sample size. CONCLUSIONS The protective efficacy of this clinical trial (50 %) was notably less than previously reported (>90 %). This may be related to differences in host genetics or the inherent variability in mosquito biting behavior and numbers of sporozoites injected. Differences in trial procedures, such as the use of leukapheresis prior to CHMI and of a longer interval between the final immunization and CHMI in these subjects compared to earlier trials, may also have reduced protective efficacy. This trial has been retrospectively registered at ISRCTN ID 17372582, May 31, 2016.
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Affiliation(s)
- Bradley W. Hickey
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Joanne M. Lumsden
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Sharina Reyes
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Martha Sedegah
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Michael R. Hollingdale
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Daniel A. Freilich
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas C. Luke
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Yupin Charoenvit
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Lucy M. Goh
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Mara P. Berzins
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Lolita Bebris
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - John B. Sacci
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Patricia De La Vega
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Ruobing Wang
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Harini Ganeshan
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Esteban N. Abot
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Daniel J. Carucci
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Denise L. Doolan
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Gary T. Brice
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Anita Kumar
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Joao Aguiar
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas B. Nutman
- />Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Susan F. Leitman
- />Department of Transfusion Medicine, National Institutes of Health Clinical Center, Bethesda, MD USA
| | - Stephen L. Hoffman
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Sanaria Inc., Rockville, MD USA
| | - Judith E. Epstein
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas L. Richie
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Sanaria Inc., Rockville, MD USA
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Abstract
INTRODUCTION Despite recent advances, malaria remains a major health threat both to populations in endemic areas as well travelers, including military personnel, to these areas. Subunit vaccines have not yet achieved sufficient efficacy needed for use in any of these at risk populations. Areas covered: This review discusses the current status of various whole sporozoite vaccine approaches and is mainly focused on current clinical trials. Expert commentary: Nearly 100% efficacy was achieved by administering multiple bites of radiation-attenuated sporozoite (RAS) Plasmodium falciparum-infected mosquitoes; this is impractical for widespread use. Now, this high level efficacy has been reproduced using purified, metabolically active RAS (PfSPZ Sanaria® Vaccine), which is undergoing extensive clinical testing. Alternative whole sporozoite vaccines include immunization with fully infectious sporozoites under chloroquine prophylaxis (CPS) or as genetically-attenuated parasites (GAP). By also manufacturing purified infectious sporozoites, it is now possible to combine these with CPS and GAP, as well as perform challenge studies using controlled doses of sporozoites.
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Affiliation(s)
| | - Martha Sedegah
- a Malaria Department , Naval Medical Research Center , Silver Spring , MD , USA
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Stone BC, Kas A, Billman ZP, Fuller DH, Fuller JT, Shendure J, Murphy SC. Complex Minigene Library Vaccination for Discovery of Pre-Erythrocytic Plasmodium T Cell Antigens. PLoS One 2016; 11:e0153449. [PMID: 27070430 PMCID: PMC4829254 DOI: 10.1371/journal.pone.0153449] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/30/2016] [Indexed: 01/15/2023] Open
Abstract
Development of a subunit vaccine targeting liver-stage Plasmodium parasites requires the identification of antigens capable of inducing protective T cell responses. However, traditional methods of antigen identification are incapable of evaluating T cell responses against large numbers of proteins expressed by these parasites. This bottleneck has limited development of subunit vaccines against Plasmodium and other complex intracellular pathogens. To address this bottleneck, we are developing a synthetic minigene technology for multi-antigen DNA vaccines. In an initial test of this approach, pools of long (150 bp) antigen-encoding oligonucleotides were synthesized and recombined into vectors by ligation-independent cloning to produce two DNA minigene library vaccines. Each vaccine encoded peptides derived from 36 (vaccine 1) and 53 (vaccine 2) secreted or transmembrane pre-erythrocytic P. yoelii proteins. BALB/cj mice were vaccinated three times with a single vaccine by biolistic particle delivery (gene gun) and screened for interferon-γ-producing T cell responses by ELISPOT. Library vaccination induced responses against four novel antigens. Naïve mice exposed to radiation-attenuated sporozoites mounted a response against only one of the four novel targets (PyMDH, malate dehydrogenase). The response to PyMDH could not be recalled by additional homologous sporozoite immunizations but could be partially recalled by heterologous cross-species sporozoite exposure. Vaccination against the dominant PyMDH epitope by DNA priming and recombinant Listeria boosting did not protect against sporozoite challenge. Improvements in library design and delivery, combined with methods promoting an increase in screening sensitivity, may enable complex minigene screening to serve as a high-throughput system for discovery of novel T cell antigens.
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Affiliation(s)
- Brad C. Stone
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, United States of America
- Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- * E-mail: (BCS); (SCM)
| | - Arnold Kas
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, United States of America
- Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Zachary P. Billman
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, United States of America
- Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Deborah H. Fuller
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - James T. Fuller
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Jay Shendure
- Department of Genome Sciences, University of Washington, Seattle, Washington, United States of America
| | - Sean C. Murphy
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, United States of America
- Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
- Seattle Malaria Clinical Trials Center, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Human Challenge Center, Center for Infectious Disease Research, Seattle, Washington, United States of America
- * E-mail: (BCS); (SCM)
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Du F, Wang S, Zhao C, Cao YM, Luo EJ. Immunogenicity and immunizing protection effect of GAMA gene DNA vaccine on Plasmodium berghei. ASIAN PAC J TROP MED 2016; 9:158-63. [PMID: 26919947 DOI: 10.1016/j.apjtm.2016.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 12/20/2015] [Accepted: 12/30/2015] [Indexed: 10/22/2022] Open
Abstract
OBJECTIVE To explore the effect of immunogenicity and immunizing protection of GAMA gene DNA vaccine, which was related with merozoite, ookinete and sporozoite invasion. METHODS Gene fragments were obtained using PCR technique and eukaryotic expression vector (containing immunostimulatory sequence) was built. BALB/c mice were divided into PBS control group, empty vector control group and study group and were immunized at week 0, 3 and 6 respectively. Blood was collected 2 weeks after each immunization and serum was separated to detect the IgG, IgG1 and IgG2a levels. Spleen of mice was obtained for preparation of splenic mononuclear cell and the cytokine IL-4 and IFN-γ levels were detected. Indirect immunofluorescence and western blot were employed to verify the specificity of antiserum. Sporozoite and merozoite invasion were used respectively to detect the immune protective effect 2 weeks after the third immunization. Ookinete conversion rate in vitro and oocyst numbers of mosquito stomach were observed to evaluate the transmission-blocking levels. RESULTS In GAMA DNA vaccine group: antiserum could be combined with recombinant protein specifically and green fluorescence signals of merozoite, ookinete and sporozoite were observable, while specific fragments and fluorescence signals were not observable in empty vector group. Compared with control group, specific IgG in DNA vaccine immunity group significantly increased (P < 0.01), and IgG1 and IgG2a all increased (P < 0.01). IL-4, IFN-γ content in study group significantly increased, compared with control group (P < 0.01). GAMA DNA vaccine immunity could not obviously block the erythrocyte-stage infection (caused by sporozoite invasion); compared with control group, liver worm load was slightly reduced (P < 0.05), and antiserum ookinete numbers (cultured in vitro) had no significant difference with oocyst numbers of mosquito stomach in DNA vaccine group. CONCLUSIONS GAMA has good antigenicity, which could stimulate the body to produce specific immune responses; while DNA vaccine immunity could not play a good protective effect, the effect of which is only limited to the slight reduction of liver worm load, and has no obvious erythrocyte-stage protective effect and transmission-blocking effect. Therefore, trying other immunization strategies for further research on the value of GAMA (as multi-stage antigen vaccine and multi-stage combined vaccine components of the life-cycle of plasmodium) is necessary.
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Affiliation(s)
- Feng Du
- Department of Pathogen Biology, Basic Medical College of China Medical University, Shenyang City, Liaoning, China
| | - Si Wang
- Department of Pathogen Biology, Basic Medical College of China Medical University, Shenyang City, Liaoning, China
| | - Chen Zhao
- Inspection Institute of Jilin Medical College, China
| | - Ya-Ming Cao
- Department of Immunology, Basic Medical College of China Medical University, Shenyang City, Liaoning, China
| | - En-Jie Luo
- Department of Pathogen Biology, Basic Medical College of China Medical University, Shenyang City, Liaoning, China.
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