1
|
Wistuba-Hamprecht J, Reuter B, Fendel R, Hoffman SL, Campo JJ, Felgner PL, Kremsner PG, Mordmüller B, Pfeifer N. Machine learning prediction of malaria vaccine efficacy based on antibody profiles. PLoS Comput Biol 2024; 20:e1012131. [PMID: 38848436 PMCID: PMC11189177 DOI: 10.1371/journal.pcbi.1012131] [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: 10/05/2021] [Revised: 06/20/2024] [Accepted: 05/02/2024] [Indexed: 06/09/2024] Open
Abstract
Immunization through repeated direct venous inoculation of Plasmodium falciparum (Pf) sporozoites (PfSPZ) under chloroquine chemoprophylaxis, using the PfSPZ Chemoprophylaxis Vaccine (PfSPZ-CVac), induces high-level protection against controlled human malaria infection (CHMI). Humoral and cellular immunity contribute to vaccine efficacy but only limited information about the implicated Pf-specific antigens is available. Here, we examined Pf-specific antibody profiles, measured by protein arrays representing the full Pf proteome, of 40 placebo- and PfSPZ-immunized malaria-naïve volunteers from an earlier published PfSPZ-CVac dose-escalation trial. For this purpose, we both utilized and adapted supervised machine learning methods to identify predictive antibody profiles at two different time points: after immunization and before CHMI. We developed an adapted multitask support vector machine (SVM) approach and compared it to standard methods, i.e. single-task SVM, regularized logistic regression and random forests. Our results show, that the multitask SVM approach improved the classification performance to discriminate the protection status based on the underlying antibody-profiles while combining time- and dose-dependent data in the prediction model. Additionally, we developed the new fEature diStance exPlainabilitY (ESPY) method to quantify the impact of single antigens on the non-linear multitask SVM model and make it more interpretable. In conclusion, our multitask SVM model outperforms the studied standard approaches in regard of classification performance. Moreover, with our new explanation method ESPY, we were able to interpret the impact of Pf-specific antigen antibody responses that predict sterile protective immunity against CHMI after immunization. The identified Pf-specific antigens may contribute to a better understanding of immunity against human malaria and may foster vaccine development.
Collapse
Affiliation(s)
- Jacqueline Wistuba-Hamprecht
- Department of Computer Science, University of Tübingen, Tübingen, Germany
- Institute for Biomedical Informatics, University of Tübingen, Tübingen, Germany
| | - Bernhard Reuter
- Department of Computer Science, University of Tübingen, Tübingen, Germany
- Institute for Biomedical Informatics, University of Tübingen, Tübingen, Germany
| | - Rolf Fendel
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research, partner site Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | | | - Joseph J. Campo
- Antigen Discovery Inc., Irvine, California, United States of America
| | - Philip L. Felgner
- Department of Medicine, University of California Irvine, Irvine, California, United States of America
| | - Peter G. Kremsner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- German Center for Infection Research, partner site Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Nico Pfeifer
- Department of Computer Science, University of Tübingen, Tübingen, Germany
- Institute for Biomedical Informatics, University of Tübingen, Tübingen, Germany
- German Center for Infection Research, partner site Tübingen, Tübingen, Germany
| |
Collapse
|
2
|
Zhou X, Zhang Q, Chen JH, Dai JF, Kassegne K. Revisiting the antigen markers of vector-borne parasitic diseases identified by immunomics: identification and application to disease control. Expert Rev Proteomics 2024; 21:205-216. [PMID: 38584506 DOI: 10.1080/14789450.2024.2336994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 03/03/2024] [Indexed: 04/09/2024]
Abstract
INTRODUCTION Protein microarray is a promising immunomic approach for identifying biomarkers. Based on our previous study that reviewed parasite antigens and recent parasitic omics research, this article expands to include information on vector-borne parasitic diseases (VBPDs), namely, malaria, schistosomiasis, leishmaniasis, babesiosis, trypanosomiasis, lymphatic filariasis, and onchocerciasis. AREAS COVERED We revisit and systematically summarize antigen markers of vector-borne parasites identified by the immunomic approach and discuss the latest advances in identifying antigens for the rational development of diagnostics and vaccines. The applications and challenges of this approach for VBPD control are also discussed. EXPERT OPINION The immunomic approach has enabled the identification and/or validation of antigen markers for vaccine development, diagnosis, disease surveillance, and treatment. However, this approach presents several challenges, including limited sample size, variability in antigen expression, false-positive results, complexity of omics data, validation and reproducibility, and heterogeneity of diseases. In addition, antigen involvement in host immune evasion and antigen sensitivity/specificity are major issues in its application. Despite these limitations, this approach remains promising for controlling VBPD. Advances in technology and data analysis methods should continue to improve candidate antigen identification, as well as the use of a multiantigen approach in diagnostic and vaccine development for VBPD control.
Collapse
Affiliation(s)
- Xia Zhou
- MOE Key Laboratory of Geriatric Diseases and Immunology, School of Biology & Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Qianqian Zhang
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Jun-Hu Chen
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research); National Health Commission of the People's Republic of China (NHC) Key Laboratory of Parasite and Vector Biology; World Health Organization (WHO) Collaborating Center for Tropical Diseases; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China
- Hainan Tropical Diseases Research Center (Hainan Sub-Center, Chinese Center for Tropical Diseases Research), Haikou, China
| | - Jian-Feng Dai
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Kokouvi Kassegne
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- One Health Center, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
3
|
Mazhari R, Takashima E, Longley RJ, Ruybal-Pesantez S, White MT, Kanoi BN, Nagaoka H, Kiniboro B, Siba P, Tsuboi T, Mueller I. Identification of novel Plasmodium vivax proteins associated with protection against clinical malaria. Front Cell Infect Microbiol 2023; 13:1076150. [PMID: 36761894 PMCID: PMC9905245 DOI: 10.3389/fcimb.2023.1076150] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 01/09/2023] [Indexed: 01/26/2023] Open
Abstract
As progress towards malaria elimination continues, the challenge posed by the parasite species Plasmodium vivax has become more evident. In many regions co-endemic for P. vivax and Plasmodium falciparum, as transmission has declined the proportion of cases due to P. vivax has increased. Novel tools that directly target P. vivax are thus warranted for accelerated elimination. There is currently no advanced vaccine for P. vivax and only a limited number of potential candidates in the pipeline. In this study we aimed to identify promising P. vivax proteins that could be used as part of a subunit vaccination approach. We screened 342 P. vivax protein constructs for their ability to induce IgG antibody responses associated with protection from clinical disease in a cohort of children from Papua New Guinea. This approach has previously been used to successfully identify novel candidates. We were able to confirm previous results from our laboratory identifying the proteins reticulocyte binding protein 2b and StAR-related lipid transfer protein, as well as at least four novel candidates with similar levels of predicted protective efficacy. Assessment of these P. vivax proteins in further studies to confirm their potential and identify functional mechanisms of protection against clinical disease are warranted.
Collapse
Affiliation(s)
- Ramin Mazhari
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Rhea J Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Shazia Ruybal-Pesantez
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Michael T White
- Institut Pasteur, Université de Paris Cité, G5 Épidémiologie et Analyse des Maladies Infectieuses, Département de Santé Globale, Paris, France
| | - Bernard N Kanoi
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Benson Kiniboro
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Peter Siba
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Takafumi Tsuboi
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
4
|
Takashima E, Kanoi BN, Nagaoka H, Morita M, Hassan I, Palacpac NMQ, Egwang TG, Horii T, Gitaka J, Tsuboi T. Meta-Analysis of Human Antibodies Against Plasmodium falciparum Variable Surface and Merozoite Stage Antigens. Front Immunol 2022; 13:887219. [PMID: 35757771 PMCID: PMC9218060 DOI: 10.3389/fimmu.2022.887219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/11/2022] [Indexed: 11/30/2022] Open
Abstract
Concerted efforts to fight malaria have caused significant reductions in global malaria cases and mortality. Sustaining this will be critical to avoid rebound and outbreaks of seasonal malaria. Identifying predictive attributes that define clinical malaria will be key to guide development of second-generation tools to fight malaria. Broadly reactive antibodies against variable surface antigens that are expressed on the surface of infected erythrocytes and merozoites stage antigens are targets of naturally acquired immunity and prime candidates for anti-malaria therapeutics and vaccines. However, predicting the relationship between the antigen-specific antibodies and protection from clinical malaria remains unresolved. Here, we used new datasets and multiple approaches combined with re-analysis of our previous data to assess the multi-dimensional and complex relationship between antibody responses and clinical malaria outcomes. We observed 22 antigens (17 PfEMP1 domains, 3 RIFIN family members, merozoite surface protein 3 (PF3D7_1035400), and merozoites-associated armadillo repeats protein (PF3D7_1035900) that were selected across three different clinical malaria definitions (1,000/2,500/5,000 parasites/µl plus fever). In addition, Principal Components Analysis (PCA) indicated that the first three components (Dim1, Dim2 and Dim3 with eigenvalues of 306, 48, and 29, respectively) accounted for 66.1% of the total variations seen. Specifically, the Dim1, Dim2 and Dim3 explained 52.8%, 8.2% and 5% of variability, respectively. We further observed a significant relationship between the first component scores and age with antibodies to PfEMP1 domains being the key contributing variables. This is consistent with a recent proposal suggesting that there is an ordered acquisition of antibodies targeting PfEMP1 proteins. Thus, although limited, and further work on the significance of the selected antigens will be required, these approaches may provide insights for identification of drivers of naturally acquired protective immunity as well as guide development of additional tools for malaria elimination and eradication.
Collapse
Affiliation(s)
- Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Bernard N Kanoi
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Ifra Hassan
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Nirianne M Q Palacpac
- Department of Malaria Vaccine Development, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | | | - Toshihiro Horii
- Department of Malaria Vaccine Development, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Jesse Gitaka
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
| | - Takafumi Tsuboi
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama, Japan
| |
Collapse
|
5
|
Tayipto Y, Liu Z, Mueller I, Longley RJ. Serology for Plasmodium vivax surveillance: A novel approach to accelerate towards elimination. Parasitol Int 2021; 87:102492. [PMID: 34728377 DOI: 10.1016/j.parint.2021.102492] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/30/2021] [Accepted: 10/28/2021] [Indexed: 01/13/2023]
Abstract
Plasmodium vivax is the most widespread causative agent of human malaria in the world. Despite the ongoing implementation of malaria control programs, the rate of case reduction has declined over the last 5 years. Hence, surveillance of malaria transmission should be in place to identify and monitor areas that require intensified malaria control interventions. Serological tools may offer additional insights into transmission intensity over parasite and entomological measures, especially as transmission levels decline. Antibodies can be detected in the host system for months to even years after parasite infections have been cleared from the blood, enabling malaria exposure history to be captured. Because the Plasmodium parasite expresses more than 5000 proteins, it is important to a) understand antibody longevity following infection and b) measure antibodies to more than one antigen in order to accurately inform on the exposure and/or immune status of populations. This review summarises current practices for surveillance of P. vivax malaria, the current state of research into serological exposure markers and their potential role for accelerating malaria elimination, and discusses further studies that need to be undertaken to see such technology implemented in malaria-endemic areas.
Collapse
Affiliation(s)
- Yanie Tayipto
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Zoe Liu
- The Institute for Mental and Physical Health and Clinical Translation, Barwon Health, Deakin University, Geelong, Victoria, Australia; School of Medicine, Centre for Molecular and Medical Research, Deakin University, Geelong, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Rhea J Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.
| |
Collapse
|
6
|
Sahu PK, Duffy FJ, Dankwa S, Vishnyakova M, Majhi M, Pirpamer L, Vigdorovich V, Bage J, Maharana S, Mandala W, Rogerson SJ, Seydel KB, Taylor TE, Kim K, Sather DN, Mohanty A, Mohanty RR, Mohanty A, Pattnaik R, Aitchison JD, Hoffman A, Mohanty S, Smith JD, Bernabeu M, Wassmer SC. Determinants of brain swelling in pediatric and adult cerebral malaria. JCI Insight 2021; 6:145823. [PMID: 34549725 PMCID: PMC8492338 DOI: 10.1172/jci.insight.145823] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 07/28/2021] [Indexed: 01/08/2023] Open
Abstract
Cerebral malaria (CM) affects children and adults, but brain swelling is more severe in children. To investigate features associated with brain swelling in malaria, we performed blood profiling and brain MRI in a cohort of pediatric and adult patients with CM in Rourkela, India, and compared them with an African pediatric CM cohort in Malawi. We determined that higher plasma Plasmodium falciparum histidine rich protein 2 (PfHRP2) levels and elevated var transcripts that encode for binding to endothelial protein C receptor (EPCR) were linked to CM at both sites. Machine learning models trained on the African pediatric cohort could classify brain swelling in Indian children CM cases but had weaker performance for adult classification, due to overall lower parasite var transcript levels in this age group and more severe thrombocytopenia in Rourkela adults. Subgrouping of patients with CM revealed higher parasite biomass linked to severe thrombocytopenia and higher Group A–EPCR var transcripts in mild thrombocytopenia. Overall, these findings provide evidence that higher parasite biomass and a subset of Group A–EPCR binding variants are common features in children and adult CM cases, despite age differences in brain swelling.
Collapse
Affiliation(s)
- Praveen K Sahu
- Center for the Study of Complex Malaria in India, Ispat General Hospital (IGH), Rourkela, Odisha, India
| | - Fergal J Duffy
- Seattle Children's Research Institute, Seattle, Washington, USA
| | - Selasi Dankwa
- Seattle Children's Research Institute, Seattle, Washington, USA
| | | | | | - Lukas Pirpamer
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Jabamani Bage
- Center for the Study of Complex Malaria in India, Ispat General Hospital (IGH), Rourkela, Odisha, India
| | - Sameer Maharana
- Center for the Study of Complex Malaria in India, Ispat General Hospital (IGH), Rourkela, Odisha, India
| | - Wilson Mandala
- Malawi University of Science and Technology, Limbe, Malawi
| | - Stephen J Rogerson
- Department of Medicine, The Doherty Institute, University of Melbourne, Melbourne, Australia
| | - Karl B Seydel
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA.,Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Terrie E Taylor
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA.,Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Kami Kim
- Division of Infectious Diseases and International Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - D Noah Sather
- Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Akshaya Mohanty
- Infectious Diseases Biology Unit, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | | | - Anita Mohanty
- Department of Intensive Care, IGH, Rourkela, Odisha, India
| | | | - John D Aitchison
- Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Angelika Hoffman
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany.,University Institute of Diagnostic and Interventional Neuroradiology, University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Sanjib Mohanty
- Center for the Study of Complex Malaria in India, Ispat General Hospital (IGH), Rourkela, Odisha, India
| | - Joseph D Smith
- Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Maria Bernabeu
- Seattle Children's Research Institute, Seattle, Washington, USA.,European Molecular Biology Laboratory (EMBL), Barcelona, Spain
| | - Samuel C Wassmer
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| |
Collapse
|
7
|
Acquisition and decay of IgM and IgG responses to merozoite antigens after Plasmodium falciparum malaria in Ghanaian children. PLoS One 2020; 15:e0243943. [PMID: 33332459 PMCID: PMC7746192 DOI: 10.1371/journal.pone.0243943] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022] Open
Abstract
Developing a vaccine against Plasmodium falciparum malaria has been challenging, primarily due to high levels of antigen polymorphism and a complex parasite lifecycle. Immunization with the P. falciparum merozoite antigens PfMSRP5, PfSERA9, PfRAMA, PfCyRPA and PfRH5 has been shown to give rise to growth inhibitory and synergistic antisera. Therefore, these five merozoite proteins are considered to be promising candidates for a second-generation multivalent malaria vaccine. Nevertheless, little is known about IgG and IgM responses to these antigens in populations that are naturally exposed to P. falciparum. In this study, serum samples from clinically immune adults and malaria exposed children from Ghana were studied to compare levels of IgG and IgM specific for PfMSRP5, PfSERA9, PfRAMA, PfCyRPA and PfRH5. All five antigens were found to be specifically recognized by both IgM and IgG in serum from clinically immune adults and from children with malaria. Longitudinal analysis of the latter group showed an early, transient IgM response that was followed by IgG, which peaked 14 days after the initial diagnosis. IgG levels and parasitemia did not correlate, whereas parasitemia was weakly positively correlated with IgM levels. These findings show that IgG and IgM specific for merozoite antigens PfMSRP5, PfSERA9, PfRAMA, PfCyRPA and PfRH5 are high in children during P. falciparum malaria, but that the IgM induction and decline occurs earlier in infection than that of IgG.
Collapse
|
8
|
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.
Collapse
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.
| |
Collapse
|
9
|
Chan LJ, Dietrich MH, Nguitragool W, Tham WH. Plasmodium vivax Reticulocyte Binding Proteins for invasion into reticulocytes. Cell Microbiol 2019; 22:e13110. [PMID: 31469946 PMCID: PMC7003471 DOI: 10.1111/cmi.13110] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/25/2019] [Accepted: 08/25/2019] [Indexed: 12/22/2022]
Abstract
Plasmodium vivax is responsible for most of the malaria infections outside Africa and is currently the predominant malaria parasite in countries under elimination programs. P. vivax preferentially enters young red cells called reticulocytes. Advances in understanding the molecular and cellular mechanisms of entry are hampered by the inability to grow large numbers of P. vivax parasites in a long‐term in vitro culture. Recent progress in understanding the biology of the P. vivax Reticulocyte Binding Protein (PvRBPs) family of invasion ligands has led to the identification of a new invasion pathway into reticulocytes, an understanding of their structural architecture and PvRBPs as targets of the protective immune response to P. vivax infection. This review summarises current knowledge on the role of reticulocytes in P. vivax infection, the function of the PvRBP family of proteins in generating an immune response in human populations, and the characterization of anti‐PvRBP antibodies in blocking parasite invasion.
Collapse
Affiliation(s)
- Li-Jin Chan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Melanie H Dietrich
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Wang Nguitragool
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Wai-Hong Tham
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, Australia
| |
Collapse
|
10
|
Abstract
A single exposure to many viral and bacterial pathogens typically induces life-long immunity, however, the development of the protective immunity to Plasmodium parasites is strikingly less efficient and achieves only partial protection, with adults residing in endemic areas often experiencing asymptomatic infections. Although naturally acquired immunity to malaria requires both cell-mediated and humoral immune responses, antibodies govern the control of malarial disease caused by the blood-stage form of the parasites. A large body of epidemiological evidence described that antibodies to Plasmodium antigens are inefficiently generated and rapidly lost without continued parasite exposure, suggesting that malaria is accompanied by defects in the development of immunological B cell memory. This topic has been of focus of recent studies of malaria infection in humans and mice. This review examines the main findings to date on the processes that modulate the acquisition of memory B cell responses to malaria, and highlights the importance of closing outstanding gaps of knowledge in the field for the rational design of next generation therapeutics against malaria.
Collapse
Affiliation(s)
- Ann Ly
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Diana S Hansen
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| |
Collapse
|
11
|
Abstract
The enzyme-linked immunosorbent assay (ELISA) is a reliable and relatively low-cost method for measuring soluble ligands such as antibodies and proteins in biological samples. For analysis of specific antibodies in serum, a capture antigen is immobilized onto a solid polystyrene surface from which it can capture the antibodies. The captured antibodies are subsequently detected using a secondary antibody conjugated to an enzyme. Detection is accomplished by addition of a colorimetric substrate, and the readout is absorbance (optical density). Here, we provide a detailed standardized ELISA protocol for the quantification of antibodies against malaria antigens.
Collapse
|
12
|
Kassegne K, Abe EM, Cui YB, Chen SB, Xu B, Deng WP, Shen HM, Wang Y, Chen JH, Zhou XN. Contribution of Plasmodium immunomics: potential impact for serological testing and surveillance of malaria. Expert Rev Proteomics 2018; 16:117-129. [PMID: 30513025 DOI: 10.1080/14789450.2019.1554441] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Introduction: Plasmodium vivax (Pv) and P. knowlesi account together for a considerable share of the global burden of malaria, along with P. falciparum (Pf). However, inaccurate diagnosis and undetectable asymptomatic/submicroscopic malaria infections remain very challenging. Blood-stage antigens involved in either invasion of red blood cells or sequestration/cytoadherence of parasitized erythrocytes have been immunomics-characterized, and are vital for the detection of malaria incidence. Areas covered: We review the recent advances in Plasmodium immunomics to discuss serological markers with potential for specific and sensitive diagnosis of malaria. Insights on alternative use of immunomics to assess malaria prevalence are also highlighted. Finally, we provide practical applications of serological markers as diagnostics, with an emphasis on dot immunogold filtration assay which holds promise for malaria diagnosis and epidemiological surveys. Expert commentary: The approach largely contributes to Pf and Pv research in identifying promising non-orthologous antigens able to detect malaria incidence and to differentiate between past and recent infections. However, further studies to profiling naturally acquired immune responses are expected in order to help discover/validate serological markers of no cross-seroreactivity and guide control interventions. More so, the application of immunomics to knowlesi infections would help validate the recently identified antigens and contribute to the discovery of additional biomarkers of exposure, immunity, or both.
Collapse
Affiliation(s)
- Kokouvi Kassegne
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Eniola Michael Abe
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Yan-Bing Cui
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Shen-Bo Chen
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Bin Xu
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Wang-Ping Deng
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Hai-Mo Shen
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Yue Wang
- b Institute of Parasitic Diseases , Zhejiang Academy of Medical Sciences , Hangzhou , People's Republic of China
| | - Jun-Hu Chen
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| | - Xiao-Nong Zhou
- a National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health , National Centre for International Research on Tropical Diseases, WHO Collaborating Center for Tropical Diseases, Shanghai, People's Republic of China
| |
Collapse
|
13
|
Silveira ELV, Dominguez MR, Soares IS. To B or Not to B: Understanding B Cell Responses in the Development of Malaria Infection. Front Immunol 2018; 9:2961. [PMID: 30619319 PMCID: PMC6302011 DOI: 10.3389/fimmu.2018.02961] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 12/03/2018] [Indexed: 12/18/2022] Open
Abstract
Malaria is a widespread disease caused mainly by the Plasmodium falciparum (Pf) and Plasmodium vivax (Pv) protozoan parasites. Depending on the parasite responsible for the infection, high morbidity and mortality can be triggered. To escape the host immune responses, Plasmodium parasites disturb the functionality of B cell subsets among other cell types. However, some antibodies elicited during a malaria infection have the potential to block pathogen invasion and dissemination into the host. Thus, the question remains, why is protection not developed and maintained after the primary parasite exposure? In this review, we discuss different aspects of B cell responses against Plasmodium antigens during malaria infection. Since most studies have focused on the quantification of serum antibody titers, those B cell responses have not been fully characterized. However, to secrete antibodies, a complex cellular response is set up, including not only the activation and differentiation of B cells into antibody-secreting cells, but also the participation of other cell subsets in the germinal center reactions. Therefore, a better understanding of how B cell subsets are stimulated during malaria infection will provide essential insights toward the design of potent interventions.
Collapse
Affiliation(s)
- Eduardo L V Silveira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mariana R Dominguez
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Irene S Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
14
|
Kamuyu G, Tuju J, Kimathi R, Mwai K, Mburu J, Kibinge N, Chong Kwan M, Hawkings S, Yaa R, Chepsat E, Njunge JM, Chege T, Guleid F, Rosenkranz M, Kariuki CK, Frank R, Kinyanjui SM, Murungi LM, Bejon P, Färnert A, Tetteh KKA, Beeson JG, Conway DJ, Marsh K, Rayner JC, Osier FHA. KILchip v1.0: A Novel Plasmodium falciparum Merozoite Protein Microarray to Facilitate Malaria Vaccine Candidate Prioritization. Front Immunol 2018; 9:2866. [PMID: 30619257 PMCID: PMC6298441 DOI: 10.3389/fimmu.2018.02866] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/21/2018] [Indexed: 12/12/2022] Open
Abstract
Passive transfer studies in humans clearly demonstrated the protective role of IgG antibodies against malaria. Identifying the precise parasite antigens that mediate immunity is essential for vaccine design, but has proved difficult. Completion of the Plasmodium falciparum genome revealed thousands of potential vaccine candidates, but a significant bottleneck remains in their validation and prioritization for further evaluation in clinical trials. Focusing initially on the Plasmodium falciparum merozoite proteome, we used peer-reviewed publications, multiple proteomic and bioinformatic approaches, to select and prioritize potential immune targets. We expressed 109 P. falciparum recombinant proteins, the majority of which were obtained using a mammalian expression system that has been shown to produce biologically functional extracellular proteins, and used them to create KILchip v1.0: a novel protein microarray to facilitate high-throughput multiplexed antibody detection from individual samples. The microarray assay was highly specific; antibodies against P. falciparum proteins were detected exclusively in sera from malaria-exposed but not malaria-naïve individuals. The intensity of antibody reactivity varied as expected from strong to weak across well-studied antigens such as AMA1 and RH5 (Kruskal–Wallis H test for trend: p < 0.0001). The inter-assay and intra-assay variability was minimal, with reproducible results obtained in re-assays using the same chip over a duration of 3 months. Antibodies quantified using the multiplexed format in KILchip v1.0 were highly correlated with those measured in the gold-standard monoplex ELISA [median (range) Spearman's R of 0.84 (0.65–0.95)]. KILchip v1.0 is a robust, scalable and adaptable protein microarray that has broad applicability to studies of naturally acquired immunity against malaria by providing a standardized tool for the detection of antibody correlates of protection. It will facilitate rapid high-throughput validation and prioritization of potential Plasmodium falciparum merozoite-stage antigens paving the way for urgently needed clinical trials for the next generation of malaria vaccines.
Collapse
Affiliation(s)
- Gathoni Kamuyu
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - James Tuju
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Biochemistry, Pwani University, Kilifi, Kenya
| | - Rinter Kimathi
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Kennedy Mwai
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - James Mburu
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Nelson Kibinge
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Marisa Chong Kwan
- Arrayjet, Innovative Microarray Solutions, Edinburgh, United Kingdom
| | - Sam Hawkings
- Arrayjet, Innovative Microarray Solutions, Edinburgh, United Kingdom
| | - Reuben Yaa
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Emily Chepsat
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - James M Njunge
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Timothy Chege
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Fatuma Guleid
- Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Micha Rosenkranz
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Christopher K Kariuki
- Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, Kenya.,Cellular and Molecular Immunology, Vrije Universiteit Brussels, Brussels, Belgium
| | - Roland Frank
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Samson M Kinyanjui
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Department of Biochemistry, Pwani University, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Linda M Murungi
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Anna Färnert
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Kevin K A Tetteh
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - James G Beeson
- Burnet Institute, Melbourne, VIC, Australia.,Central Clinical School, Monash University, Melbourne, VIC, Australia.,Department of Medicine, University of Melbourne, Melbourne, VIC, Australia
| | - David J Conway
- Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kevin Marsh
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.,African Academy of Sciences, Nairobi, Kenya
| | - Julian C Rayner
- Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Faith H A Osier
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.,Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany.,Department of Biochemistry, Pwani University, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
15
|
Ndungo E, Randall A, Hazen TH, Kania DA, Trappl-Kimmons K, Liang X, Barry EM, Kotloff KL, Chakraborty S, Mani S, Rasko DA, Pasetti MF. A Novel Shigella Proteome Microarray Discriminates Targets of Human Antibody Reactivity following Oral Vaccination and Experimental Challenge. mSphere 2018; 3:e00260-18. [PMID: 30068560 PMCID: PMC6070737 DOI: 10.1128/msphere.00260-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022] Open
Abstract
Shigella spp. are a major cause of diarrhea and dysentery in children under 5 years old in the developing world. The development of an effective vaccine remains a public health priority, necessitating improved understanding of immune responses to Shigella and identification of protective antigens. We report the development of a core Shigella proteome microarray consisting of 2,133 antigen targets common to all Shigella species. We evaluated the microarray with serum samples from volunteers immunized with either an inactivated whole-cell S. flexneri serotype 2a (Sf2aWC) vaccine or a live attenuated S. flexneri 2a vaccine strain (CVD 1204) or challenged with wild-type S. flexneri 2a (Sf2a challenge). Baseline reactivities to most antigens were detected postintervention in all three groups. Similar immune profiles were observed after CVD 1204 vaccination and Sf2a challenge. Antigens with the largest increases in mean reactivity postintervention were members of the type three secretion system (T3SS), some of which are regarded as promising vaccine targets: these are the invasion plasmid antigens (Ipas) IpaB, IpaC, and IpaD. In addition, new immunogenic targets (IpaA, IpaH, and SepA) were identified. Importantly, immunoreactivities to antigens in the microarray correlated well with antibody titers determined by enzyme-linked immunosorbent assay (ELISA), validating the use of the microarray platform. Finally, our analysis uncovered an immune signature consisting of three conserved proteins (IpaA, IpaB, and IpaC) that was predictive of protection against shigellosis. In conclusion, the Shigella proteome microarray is a robust platform for interrogating serological reactivity to multiple antigens at once and identifying novel targets for the development of broadly protective vaccines.IMPORTANCE Each year, more than 180 million cases of severe diarrhea caused by Shigella occur globally. Those affected (mostly children in poor regions) experience long-term sequelae that severely impair quality of life. Without a licensed vaccine, the burden of disease represents a daunting challenge. An improved understanding of immune responses to Shigella is necessary to support ongoing efforts to identify a safe and effective vaccine. We developed a microarray containing >2,000 proteins common to all Shigella species. Using sera from human adults who received a killed whole-cell or live attenuated vaccine or were experimentally challenged with virulent organisms, we identified new immune-reactive antigens and defined a T3SS protein signature associated with clinical protection.
Collapse
Affiliation(s)
- Esther Ndungo
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Arlo Randall
- Antigen Discovery, Inc., Irvine, California, USA
| | - Tracy H Hazen
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dane A Kania
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Xiaowu Liang
- Antigen Discovery, Inc., Irvine, California, USA
| | - Eileen M Barry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Karen L Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | - David A Rasko
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Marcela F Pasetti
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
16
|
Patankar S, Sharma S, Rathod PK, Duraisingh MT. Malaria in India: The Need for New Targets for Diagnosis and Detection of Plasmodium vivax. Proteomics Clin Appl 2018; 12:e1700024. [PMID: 29193853 DOI: 10.1002/prca.201700024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 08/28/2017] [Indexed: 11/08/2022]
Abstract
Plasmodium vivax is a protozoan parasite that is one of the causative agents of human malaria. Due to several occult features of its life cycle, P. vivax threatens to be a problem for the recent efforts toward elimination of malaria globally. With an emphasis on malaria elimination goals, the authors summarize the major gaps in P. vivax diagnosis and describe how proteomics technologies have begun to contribute toward the discovery of antigens that could be used for various technology platforms and applications. The authors suggest areas where, in the future, proteomics technologies could fill in gaps in P. vivax diagnosis that have proved difficult. The discovery of new parasite antigens, host responses, and immune signatures using proteomics technologies will be a key part of the global malaria elimination efforts.
Collapse
Affiliation(s)
- Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India.,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | | | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| |
Collapse
|
17
|
Blood Stage Malaria Disrupts Humoral Immunity to the Pre-erythrocytic Stage Circumsporozoite Protein. Cell Rep 2017; 17:3193-3205. [PMID: 28009289 DOI: 10.1016/j.celrep.2016.11.060] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 09/18/2016] [Accepted: 11/18/2016] [Indexed: 11/21/2022] Open
Abstract
Many current malaria vaccines target the pre-erythrocytic stage of infection in the liver. However, in malaria-endemic regions, increased blood stage exposure is associated with decreased vaccine efficacy, thereby challenging current vaccine efforts. We hypothesized that pre-erythrocytic humoral immunity is directly disrupted by blood stage infection. To investigate this possibility, we used Plasmodium-antigen tetramers to analyze B cells after infection with either late liver stage arresting parasites or wild-type parasites that progress to the blood stage. Our data demonstrate that immunoglobulin G (IgG) antibodies against the pre-erythrocytic antigen, circumsporozoite protein (CSP), are generated only in response to the attenuated, but not the wild-type, infection. Further analyses revealed that blood stage malaria inhibits CSP-specific germinal center B cell differentiation and modulates chemokine expression. This results in aberrant memory formation and the loss of a rapid secondary B cell response. These data highlight how immunization with attenuated parasites may drive optimal immunity to malaria.
Collapse
|
18
|
Kessler A, Dankwa S, Bernabeu M, Harawa V, Danziger SA, Duffy F, Kampondeni SD, Potchen MJ, Dambrauskas N, Vigdorovich V, Oliver BG, Hochman SE, Mowrey WB, MacCormick IJC, Mandala WL, Rogerson SJ, Sather DN, Aitchison JD, Taylor TE, Seydel KB, Smith JD, Kim K. Linking EPCR-Binding PfEMP1 to Brain Swelling in Pediatric Cerebral Malaria. Cell Host Microbe 2017; 22:601-614.e5. [PMID: 29107642 DOI: 10.1016/j.chom.2017.09.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/06/2017] [Accepted: 09/22/2017] [Indexed: 11/16/2022]
Abstract
Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.
Collapse
Affiliation(s)
- Anne Kessler
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Selasi Dankwa
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Maria Bernabeu
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Visopo Harawa
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi
| | | | - Fergal Duffy
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Michael J Potchen
- Department of Imaging Sciences, University of Rochester, Rochester, NY 14642, USA
| | | | | | - Brian G Oliver
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Sarah E Hochman
- Department of Medicine, New York University Langone Health, New York, NY 10016, USA
| | - Wenzhu B Mowrey
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Ian J C MacCormick
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; Department of Eye and Vision Sciences, University of Liverpool, Liverpool L69 3BX, UK
| | - Wilson L Mandala
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi; Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo BT3, Malawi
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute, The University of Melbourne, Melbourne, VIC 3000, Australia
| | - D Noah Sather
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Terrie E Taylor
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Karl B Seydel
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA.
| | - Joseph D Smith
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - Kami Kim
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA.
| |
Collapse
|
19
|
Valletta JJ, Recker M. Identification of immune signatures predictive of clinical protection from malaria. PLoS Comput Biol 2017; 13:e1005812. [PMID: 29065113 PMCID: PMC5669498 DOI: 10.1371/journal.pcbi.1005812] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 11/03/2017] [Accepted: 10/04/2017] [Indexed: 11/18/2022] Open
Abstract
Antibodies are thought to play an essential role in naturally acquired immunity to malaria. Prospective cohort studies have frequently shown how continuous exposure to the malaria parasite Plasmodium falciparum cause an accumulation of specific responses against various antigens that correlate with a decreased risk of clinical malaria episodes. However, small effect sizes and the often polymorphic nature of immunogenic parasite proteins make the robust identification of the true targets of protective immunity ambiguous. Furthermore, the degree of individual-level protection conferred by elevated responses to these antigens has not yet been explored. Here we applied a machine learning approach to identify immune signatures predictive of individual-level protection against clinical disease. We find that commonly assumed immune correlates are poor predictors of clinical protection in children. On the other hand, antibody profiles predictive of an individual's malaria protective status can be found in data comprising responses to a large set of diverse parasite proteins. We show that this pattern emerges only after years of continuous exposure to the malaria parasite, whereas susceptibility to clinical episodes in young hosts (< 10 years) cannot be ascertained by measured antibody responses alone.
Collapse
Affiliation(s)
- John Joseph Valletta
- Centre for Mathematics and the Environment, University of Exeter, Penryn Campus, Penryn, United Kingdom
| | - Mario Recker
- Centre for Mathematics and the Environment, University of Exeter, Penryn Campus, Penryn, United Kingdom
- * E-mail:
| |
Collapse
|
20
|
França CT, White MT, He WQ, Hostetler JB, Brewster J, Frato G, Malhotra I, Gruszczyk J, Huon C, Lin E, Kiniboro B, Yadava A, Siba P, Galinski MR, Healer J, Chitnis C, Cowman AF, Takashima E, Tsuboi T, Tham WH, Fairhurst RM, Rayner JC, King CL, Mueller I. Identification of highly-protective combinations of Plasmodium vivax recombinant proteins for vaccine development. eLife 2017; 6:28673. [PMID: 28949293 PMCID: PMC5655538 DOI: 10.7554/elife.28673] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 09/25/2017] [Indexed: 12/22/2022] Open
Abstract
The study of antigenic targets of naturally-acquired immunity is essential to identify and prioritize antigens for further functional characterization. We measured total IgG antibodies to 38 P. vivax antigens, investigating their relationship with prospective risk of malaria in a cohort of 1–3 years old Papua New Guinean children. Using simulated annealing algorithms, the potential protective efficacy of antibodies to multiple antigen-combinations, and the antibody thresholds associated with protection were investigated for the first time. High antibody levels to multiple known and newly identified proteins were strongly associated with protection (IRR 0.44–0.74, p<0.001–0.041). Among five-antigen combinations with the strongest protective effect (>90%), EBP, DBPII, RBP1a, CyRPA, and PVX_081550 were most frequently identified; several of them requiring very low antibody levels to show a protective association. These data identify individual antigens that should be prioritized for further functional testing and establish a clear path to testing a multicomponent P. vivax vaccine.
Collapse
Affiliation(s)
- Camila Tenorio França
- Division of Population Health and Immunity, Walter and Eliza Hall Institute, Parkville, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Michael T White
- Division of Population Health and Immunity, Walter and Eliza Hall Institute, Parkville, Australia.,MRC Center for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Wen-Qiang He
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Jessica B Hostetler
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom.,Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
| | - Jessica Brewster
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Gabriel Frato
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, United States
| | - Indu Malhotra
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, United States
| | - Jakub Gruszczyk
- Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Christele Huon
- Malaria Parasite Biology and Vaccines Unit, Institut Pasteur, Paris, France
| | - Enmoore Lin
- Malaria Immuno-Epidemiology Unit, PNG Institute of Medical Research, Yagaum, Papua New Guinea
| | - Benson Kiniboro
- Malaria Immuno-Epidemiology Unit, PNG Institute of Medical Research, Yagaum, Papua New Guinea
| | - Anjali Yadava
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, United States
| | - Peter Siba
- Malaria Immuno-Epidemiology Unit, PNG Institute of Medical Research, Yagaum, Papua New Guinea
| | - Mary R Galinski
- International Center for Malaria Research, Education, and Development, Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, United States.,Infectious Diseases Division, Department of Medicine, Emory University, Atlanta, United States
| | - Julie Healer
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Chetan Chitnis
- Malaria Parasite Biology and Vaccines Unit, Institut Pasteur, Paris, France.,International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Alan F Cowman
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Eizo Takashima
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, United States
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Wai-Hong Tham
- Department of Medical Biology, University of Melbourne, Parkville, Australia.,Division of Infection and Immunity, Walter and Eliza Hall Institute, Parkville, Australia
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Christopher L King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, United States
| | - Ivo Mueller
- Division of Population Health and Immunity, Walter and Eliza Hall Institute, Parkville, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Australia.,Malaria Parasites and Hosts Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France.,Barcelona Institute of Global Health, Barcelona, Spain
| |
Collapse
|
21
|
Longley RJ, White MT, Takashima E, Morita M, Kanoi BN, Li Wai Suen CSN, Betuela I, Kuehn A, Sripoorote P, Franca CT, Siba P, Robinson LJ, Lacerda M, Sattabongkot J, Tsuboi T, Mueller I. Naturally acquired antibody responses to more than 300 Plasmodium vivax proteins in three geographic regions. PLoS Negl Trop Dis 2017; 11:e0005888. [PMID: 28892517 PMCID: PMC5614652 DOI: 10.1371/journal.pntd.0005888] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 09/26/2017] [Accepted: 08/21/2017] [Indexed: 01/22/2023] Open
Abstract
Plasmodium vivax remains an important cause of malaria in South America and the Asia-Pacific. Naturally acquired antibody responses against multiple P. vivax proteins have been described in numerous countries, however, direct comparison of these responses has been difficult with different methodologies employed. We measured antibody responses against 307 P. vivax proteins at the time of P. vivax infection, and at 2–3 later time-points in three countries. We observed that seropositivity rates at the time of infection were highest in Thailand, followed by Brazil then PNG, reflecting the level of antigenic input. The majority of sero-reactive antigens in all sites induced short-lived antibody responses with estimated half-lives of less than 6 months, although there was a trend towards longer-lived responses in PNG children. Despite these differences, IgG seropositivity rates, magnitude and longevity were highly and significantly rank-correlated between the different regions, suggesting such features are reflective of the individual protein. In the pursuit of eliminating all species of malaria, Plasmodium vivax presents one of the most substantial challenges, particularly in countries in Asia, the Western-Pacific and South America. This is primarily due to the ability of P. vivax to cause relapse infections months to years after the initial infectious bite. In areas with low levels of malaria transmission, serology has become an increasingly useful tool for surveillance, as anti-Plasmodium antibodies can be detected in individuals long after blood-stage parasites have cleared. In this study, we provide a detailed characterisation of the antibody response generated following P. vivax infection by measuring antibodies to over 300 P. vivax antigens in three different populations in Thailand, Brazil and Papua New Guinea. The individuals in these populations were followed for up to nine months allowing us to estimate the rate at which antibodies decay over time. This improved understanding of the magnitude and dynamics of the antibody response, validated in multiple populations, will contribute to the development of serological surveillance tools needed for enhanced control and elimination of P. vivax.
Collapse
Affiliation(s)
- Rhea J. Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Michael T. White
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Bernard N. Kanoi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Connie S. N. Li Wai Suen
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Inoni Betuela
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Andrea Kuehn
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
| | - Piyarat Sripoorote
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Camila T. Franca
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Peter Siba
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Leanne J. Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Marcus Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
- Instituto de Pesquisas Leônidas e Maria Deane, Manaus, Amazonas, Brazil
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- Malaria: Parasites & Hosts Unit, Department of Parasites & Insect Vectors, Institut Pasteur, Paris, France
- * E-mail:
| |
Collapse
|
22
|
Kassegne K, Abe EM, Chen JH, Zhou XN. Immunomic approaches for antigen discovery of human parasites. Expert Rev Proteomics 2016; 13:1091-1101. [DOI: 10.1080/14789450.2016.1252675] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Kokouvi Kassegne
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Eniola Michael Abe
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, Shanghai, People’s Republic of China
| |
Collapse
|
23
|
Boyle MJ, Reiling L, Osier FH, Fowkes FJI. Recent insights into humoral immunity targeting Plasmodium falciparum and Plasmodium vivax malaria. Int J Parasitol 2016; 47:99-104. [PMID: 27451359 DOI: 10.1016/j.ijpara.2016.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/08/2016] [Accepted: 06/09/2016] [Indexed: 01/02/2023]
Abstract
Recent efforts in malaria control have led to marked reductions in malaria incidence. However, new strategies are needed to sustain malaria elimination and eradication and achieve the World Health Organization goal of a malaria-free world. The development of highly effective vaccines would contribute to this goal and would be facilitated by a comprehensive understanding of humoral immune responses targeting Plasmodium falciparum and Plasmodium vivax malaria. New tools are required to facilitate the identification of vaccine candidates and the development of vaccines that induce functional and protective immunity. Here we discuss recent published findings, and unpublished work presented at the 2016 Molecular Approaches to Malaria conference, that highlight advancements in understanding humoral immune responses in the context of vaccine development. Highlights include the increased application of 'omics' and 'Big data' platforms to identify vaccine candidates, and the identification of novel functions of antibody responses that mediate protection. The application of these strategies and a global approach will increase the likelihood of rapid development of highly efficacious vaccines.
Collapse
Affiliation(s)
- Michelle J Boyle
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria 3004, Australia; Menzies School of Medical Research, Darwin, Northern Territory 0810, Australia.
| | - Linda Reiling
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria 3004, Australia
| | - Faith H Osier
- KEMRI Centre for Geographic Medicine Research-Coast, Kilifi, Kenya
| | - Freya J I Fowkes
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria 3004, Australia; Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia; Department of Infectious Diseases, Monash University, Melbourne, Victoria 3004, Australia
| |
Collapse
|
24
|
França CT, Hostetler JB, Sharma S, White MT, Lin E, Kiniboro B, Waltmann A, Darcy AW, Li Wai Suen CSN, Siba P, King CL, Rayner JC, Fairhurst RM, Mueller I. An Antibody Screen of a Plasmodium vivax Antigen Library Identifies Novel Merozoite Proteins Associated with Clinical Protection. PLoS Negl Trop Dis 2016; 10:e0004639. [PMID: 27182597 PMCID: PMC4868274 DOI: 10.1371/journal.pntd.0004639] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 03/29/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Elimination of Plasmodium vivax malaria would be greatly facilitated by the development of an effective vaccine. A comprehensive and systematic characterization of antibodies to P. vivax antigens in exposed populations is useful in guiding rational vaccine design. METHODOLOGY/PRINCIPAL FINDINGS In this study, we investigated antibodies to a large library of P. vivax entire ectodomain merozoite proteins in 2 Asia-Pacific populations, analysing the relationship of antibody levels with markers of current and cumulative malaria exposure, and socioeconomic and clinical indicators. 29 antigenic targets of natural immunity were identified. Of these, 12 highly-immunogenic proteins were strongly associated with age and thus cumulative lifetime exposure in Solomon Islanders (P<0.001-0.027). A subset of 6 proteins, selected on the basis of immunogenicity and expression levels, were used to examine antibody levels in plasma samples from a population of young Papua New Guinean children with well-characterized individual differences in exposure. This analysis identified a strong association between reduced risk of clinical disease and antibody levels to P12, P41, and a novel hypothetical protein that has not previously been studied, PVX_081550 (IRR 0.46-0.74; P<0.001-0.041). CONCLUSION/SIGNIFICANCE These data emphasize the benefits of an unbiased screening approach in identifying novel vaccine candidate antigens. Functional studies are now required to establish whether PVX_081550 is a key component of the naturally-acquired protective immune response, a biomarker of immune status, or both.
Collapse
Affiliation(s)
- Camila T. França
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Jessica B. Hostetler
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Sumana Sharma
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Michael T. White
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Center for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Enmoore Lin
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Benson Kiniboro
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Andreea Waltmann
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Andrew W. Darcy
- National Health Training & Research Institute, Ministry of Health, Honiara, Solomon Islands
| | - Connie S. N. Li Wai Suen
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Peter Siba
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Christopher L. King
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Julian C. Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
- * E-mail: (JCR); (RMF); (IM)
| | - Rick M. Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (JCR); (RMF); (IM)
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- * E-mail: (JCR); (RMF); (IM)
| |
Collapse
|
25
|
Severe adult malaria is associated with specific PfEMP1 adhesion types and high parasite biomass. Proc Natl Acad Sci U S A 2016; 113:E3270-9. [PMID: 27185931 DOI: 10.1073/pnas.1524294113] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The interplay between cellular and molecular determinants that lead to severe malaria in adults is unexplored. Here, we analyzed parasite virulence factors in an infected adult population in India and investigated whether severe malaria isolates impair endothelial protein C receptor (EPCR), a protein involved in coagulation and endothelial barrier permeability. Severe malaria isolates overexpressed specific members of the Plasmodium falciparum var gene/PfEMP1 (P. falciparum erythrocyte membrane protein 1) family that bind EPCR, including DC8 var genes that have previously been linked to severe pediatric malaria. Machine learning analysis revealed that DC6- and DC8-encoding var transcripts in combination with high parasite biomass were the strongest indicators of patient hospitalization and disease severity. We found that DC8 CIDRα1 domains from severe malaria isolates had substantial differences in EPCR binding affinity and blockade activity for its ligand activated protein C. Additionally, even a low level of inhibition exhibited by domains from two cerebral malaria isolates was sufficient to interfere with activated protein C-barrier protective activities in human brain endothelial cells. Our findings demonstrate an interplay between parasite biomass and specific PfEMP1 adhesion types in the development of adult severe malaria, and indicate that low impairment of EPCR function may contribute to parasite virulence.
Collapse
|
26
|
Chen JH, Chen SB, Wang Y, Ju C, Zhang T, Xu B, Shen HM, Mo XJ, Molina DM, Eng M, Liang X, Gardner MJ, Wang R, Hu W. An immunomics approach for the analysis of natural antibody responses to Plasmodium vivax infection. MOLECULAR BIOSYSTEMS 2016; 11:2354-63. [PMID: 26091354 DOI: 10.1039/c5mb00330j] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High throughput immunomics is a powerful platform to discover potential targets of host immunity and develop diagnostic tests for infectious diseases. We screened the sera of Plasmodium vivax-exposed individuals to profile the antibody response to blood-stage antigens of P. vivax using a P. vivax protein microarray. A total of 1936 genes encoding the P. vivax proteins were expressed, printed and screened with sera from P. vivax-exposed individuals and normal subjects. Total of 151 (7.8% of the 1936 targets) highly immunoreactive antigens were identified, including five well-characterized antigens of P. vivax (ETRAMP11.2, Pv34, SUB1, RAP2 and MSP4). Among the highly immunoreactive antigens, 5 antigens were predicted as adhesins by MAAP, and 11 antigens were predicted as merozoite invasion-related proteins based on homology with P. falciparum proteins. There are 40 proteins that have serodiagnostic potential for antibody surveillance. These novel Plasmodium antigens identified provide the clues for understanding host immune response to P. vivax infection and the development of antibody surveillance tools.
Collapse
Affiliation(s)
- Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai 200025, People's Republic of China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
SUMMARYPlasmodium vivaxis the most geographically widespread of the malaria parasites causing human disease, yet it is comparatively understudied compared withPlasmodium falciparum.In this article we review what is known about naturally acquired immunity toP. vivax, and importantly, how this differs to that acquired againstP. falciparum.Immunity to clinicalP. vivaxinfection is acquired more quickly than toP. falciparum, and evidence suggests humans in endemic areas also have a greater capacity to mount a successful immunological memory response to this pathogen. Both of these factors give promise to the idea of a successfulP. vivaxvaccine. We review what is known about both the cellular and humoral immune response, including the role of cytokines, antibodies, immunoregulation, immune memory and immune dysfunction. Furthermore, we discuss where the future lies in terms of advancing our understanding of naturally acquired immunity toP. vivax, through the use of well-designed longitudinal epidemiological studies and modern tools available to immunologists.
Collapse
|
28
|
Galatas B, Bassat Q, Mayor A. Malaria Parasites in the Asymptomatic: Looking for the Hay in the Haystack. Trends Parasitol 2015; 32:296-308. [PMID: 26708404 DOI: 10.1016/j.pt.2015.11.015] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/21/2015] [Accepted: 11/24/2015] [Indexed: 12/11/2022]
Abstract
With malaria elimination back on the international agenda, programs face the challenge of targeting all Plasmodium infections, not only symptomatic cases. As asymptomatic individuals are unlikely to seek treatment, they are missed by passive surveillance while remaining infectious to mosquitoes, thus acting as silent reservoirs of transmission. To estimate the risk of asymptomatic infections in various phases of malaria elimination, we need a deeper understanding of the underlying mechanisms favoring carriage over disease, which may involve both pathogen and host factors. Here we review our current knowledge on the determinants leading to Plasmodium falciparum symptomless infections. Understanding the host-pathogen interactions that are most likely to affect transitions between malaria disease states could guide the development of tools to tackle asymptomatic carriers in elimination settings.
Collapse
Affiliation(s)
- Beatriz Galatas
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Quique Bassat
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Alfredo Mayor
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.
| |
Collapse
|
29
|
King CL, Davies DH, Felgner P, Baum E, Jain A, Randall A, Tetteh K, Drakeley CJ, Greenhouse B. Biosignatures of Exposure/Transmission and Immunity. Am J Trop Med Hyg 2015; 93:16-27. [PMID: 26259938 PMCID: PMC4574271 DOI: 10.4269/ajtmh.15-0037] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 06/05/2015] [Indexed: 12/26/2022] Open
Abstract
A blood test that captures cumulative exposure over time and assesses levels of naturally acquired immunity (NAI) would provide a critical tool to monitor the impact of interventions to reduce malaria transmission and broaden our understanding of how NAI develops around the world as a function of age and exposure. This article describes a collaborative effort in multiple International Centers of Excellence in Malaria Research (ICEMRs) to develop such tests using malaria-specific antibody responses as biosignatures of transmission and immunity. The focus is on the use of Plasmodium falciparum and Plasmodium vivax protein microarrays to identify a panel of the most informative antibody responses in diverse malaria-endemic settings representing an unparalleled spectrum of malaria transmission and malaria species mixes before and after interventions to reduce malaria transmission.
Collapse
Affiliation(s)
- Christopher L. King
- * Address correspondence to Christopher L. King, Case Western Reserve University School of Medicine, Biomedical Research Building Room 421, Cleveland, OH 44106, E-mail: or D. Huw Davies, Division of Infectious Diseases, Department of Medicine, University of California, Irvine, Irvine, CA, 92697. E-mail:
| | - D. Huw Davies
- * Address correspondence to Christopher L. King, Case Western Reserve University School of Medicine, Biomedical Research Building Room 421, Cleveland, OH 44106, E-mail: or D. Huw Davies, Division of Infectious Diseases, Department of Medicine, University of California, Irvine, Irvine, CA, 92697. E-mail:
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Chuquiyauri R, Molina DM, Moss EL, Wang R, Gardner MJ, Brouwer KC, Torres S, Gilman RH, Llanos-Cuentas A, Neafsey DE, Felgner P, Liang X, Vinetz JM. Genome-Scale Protein Microarray Comparison of Human Antibody Responses in Plasmodium vivax Relapse and Reinfection. Am J Trop Med Hyg 2015; 93:801-9. [PMID: 26149860 DOI: 10.4269/ajtmh.15-0232] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 05/13/2015] [Indexed: 11/07/2022] Open
Abstract
Large scale antibody responses in Plasmodium vivax malaria remains unexplored in the endemic setting. Protein microarray analysis of asexual-stage P. vivax was used to identify antigens recognized in sera from residents of hypoendemic Peruvian Amazon. Over 24 months, of 106 participants, 91 had two symptomatic P. vivax malaria episodes, 11 had three episodes, 3 had four episodes, and 1 had five episodes. Plasmodium vivax relapse was distinguished from reinfection by a merozoite surface protein-3α restriction fragment length polymorphism polymerase chain reaction (MSP3α PCR-RFLP) assay. Notably, P. vivax reinfection subjects did not have higher reactivity to the entire set of recognized P. vivax blood-stage antigens than relapse subjects, regardless of the number of malaria episodes. The most highly recognized P. vivax proteins were MSP 4, 7, 8, and 10 (PVX_003775, PVX_082650, PVX_097625, and PVX_114145); sexual-stage antigen s16 (PVX_000930); early transcribed membrane protein (PVX_090230); tryptophan-rich antigen (Pv-fam-a) (PVX_092995); apical merozoite antigen 1 (PVX_092275); and proteins of unknown function (PVX_081830, PVX_117680, PVX_118705, PVX_121935, PVX_097730, PVX_110935, PVX_115450, and PVX_082475). Genes encoding reactive proteins exhibited a significant enrichment of non-synonymous nucleotide variation, an observation suggesting immune selection. These data identify candidates for seroepidemiological tools to support malaria elimination efforts in P. vivax-endemic regions.
Collapse
Affiliation(s)
- Raul Chuquiyauri
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Douglas M Molina
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Eli L Moss
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Ruobing Wang
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Malcolm J Gardner
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Kimberly C Brouwer
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Sonia Torres
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Robert H Gilman
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Alejandro Llanos-Cuentas
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Daniel E Neafsey
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Philip Felgner
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Xiaowu Liang
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Joseph M Vinetz
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, La Jolla, California; Laboratorio ICEMR-Amazonia, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Perú; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú; Antigen Discovery Inc., Irvine, California; Malaria Research Group, Broad Institute of MIT and Harvard University, Cambridge, Massachusetts; Seattle Biomed, Seattle, Washington; Department of Medicine, Division of Global Public Health, University of California San Diego, La Jolla, California; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| |
Collapse
|