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Martinez FJ, White M, Guillotte-Blisnick M, Huon C, Boucharlat A, Agou F, England P, Popovici J, Hou MM, Silk SE, Barrett JR, Nielsen CM, Reimer JM, Mukherjee P, Chauhan VS, Minassian AM, Draper SJ, Chitnis CE. PvDBPII elicits multiple antibody-mediated mechanisms that reduce growth in a Plasmodium vivax challenge trial. NPJ Vaccines 2024; 9:10. [PMID: 38184681 PMCID: PMC10771494 DOI: 10.1038/s41541-023-00796-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 12/07/2023] [Indexed: 01/08/2024] Open
Abstract
The receptor-binding domain, region II, of the Plasmodium vivax Duffy binding protein (PvDBPII) binds the Duffy antigen on the reticulocyte surface to mediate invasion. A heterologous vaccine challenge trial recently showed that a delayed dosing regimen with recombinant PvDBPII SalI variant formulated with adjuvant Matrix-MTM reduced the in vivo parasite multiplication rate (PMR) in immunized volunteers challenged with the Thai P. vivax isolate PvW1. Here, we describe extensive analysis of the polyfunctional antibody responses elicited by PvDBPII immunization and identify immune correlates for PMR reduction. A classification algorithm identified antibody features that significantly contribute to PMR reduction. These included antibody titre, receptor-binding inhibitory titre, dissociation constant of the PvDBPII-antibody interaction, complement C1q and Fc gamma receptor binding and specific IgG subclasses. These data suggest that multiple immune mechanisms elicited by PvDBPII immunization are likely to be associated with protection and the immune correlates identified could guide the development of an effective vaccine for P. vivax malaria. Importantly, all the polyfunctional antibody features that correlated with protection cross-reacted with both PvDBPII SalI and PvW1 variants, suggesting that immunization with PvDBPII should protect against diverse P. vivax isolates.
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Affiliation(s)
- Francisco J Martinez
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France
| | - Michael White
- Infectious Disease Epidemiology and Analytics G5 Unit, Institut Pasteur, Université Paris Cité, Paris, France
| | | | - Christèle Huon
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France
| | - Alix Boucharlat
- Chemogenomic and Biological Screening Core Facility, C2RT, Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Paris, France
| | - Fabrice Agou
- Chemogenomic and Biological Screening Core Facility, C2RT, Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Paris, France
| | - Patrick England
- Molecular Biophysics Facility, CNRS UMR 3528, Institut Pasteur, Paris, France
| | - Jean Popovici
- Malaria Reasearch Unit, Institut Pasteur du Cambodge, Pnom Penh, Cambodia
| | - Mimi M Hou
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Sarah E Silk
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Jordan R Barrett
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Carolyn M Nielsen
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | | | | | - Virander S Chauhan
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Angela M Minassian
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Simon J Draper
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Chetan E Chitnis
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France.
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Núñez A, Ntumngia FB, Guerra Y, Adams JH, Sáenz FE. Genetic diversity and natural selection of Plasmodium vivax reticulocyte invasion genes in Ecuador. Malar J 2023; 22:225. [PMID: 37537581 PMCID: PMC10398936 DOI: 10.1186/s12936-023-04640-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Knowledge of the diversity of invasion ligands in malaria parasites in endemic regions is essential to understand how natural selection influences genetic diversity of these ligands and their feasibility as possible targets for future vaccine development. In this study the diversity of four genes for merozoite invasion ligands was studied in Ecuadorian isolates of Plasmodium vivax. METHODS Eighty-eight samples from P. vivax infected individuals from the Coast and Amazon region of Ecuador were obtained between 2012 and 2015. The merozoite invasion genes pvmsp-1-19, pvdbpII, pvrbp1a-2 and pvama1 were amplified, sequenced, and compared to the Sal-1 strain. Polymorphisms were mapped and genetic relationships between haplotypes were determined. RESULTS Only one nonsynonymous polymorphism was detected in pvmsp-1-19, while 44 nonsynonymous polymorphisms were detected in pvdbpII, 56 in pvrbp1a-2 and 33 in pvama1. While haplotypes appeared to be more related within each area of study and there was less relationship between parasites of the coastal and Amazon regions of the country, diversification processes were observed in the two Amazon regions. The highest haplotypic diversity for most genes occurred in the East Amazon of the country. The high diversity observed in Ecuadorian samples is closer to Brazilian and Venezuelan isolates, but lower than reported in other endemic regions. In addition, departure from neutrality was observed in Ecuadorian pvama1. Polymorphisms for pvdbpII and pvama1 were associated to B-cell epitopes. CONCLUSIONS pvdbpII and pvama1 genetic diversity found in Ecuadorian P. vivax was very similar to that encountered in other malaria endemic countries with varying transmission levels and segregated by geographic region. The highest diversity of P. vivax invasion genes in Ecuador was found in the Amazonian region. Although selection appeared to have small effect on pvdbpII and pvrbp1a-2, pvama1 was influenced by significant balancing selection.
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Affiliation(s)
- Andrés Núñez
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Francis B Ntumngia
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, FL, Tampa, USA
| | - Yasel Guerra
- Grupo de Bio-Quimioinformática, Universidad de Las Américas, Quito, Ecuador
| | - John H Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, FL, Tampa, USA
| | - Fabián E Sáenz
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
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Kar S, Sinha A. Plasmodium vivax Duffy Binding Protein-Based Vaccine: a Distant Dream. Front Cell Infect Microbiol 2022; 12:916702. [PMID: 35909975 PMCID: PMC9325973 DOI: 10.3389/fcimb.2022.916702] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 06/21/2022] [Indexed: 11/13/2022] Open
Abstract
The neglected but highly prevalent Plasmodium vivax in South-east Asia and South America poses a great challenge, with regards to long-term in-vitro culturing and heavily limited functional assays. Such visible challenges as well as narrowed progress in development of experimental research tools hinders development of new drugs and vaccines. The leading vaccine candidate antigen Plasmodium vivax Duffy Binding Protein (PvDBP), is essential for reticulocyte invasion by binding to its cognate receptor, the Duffy Antigen Receptor for Chemokines (DARC), on the host’s reticulocyte surface. Despite its highly polymorphic nature, the amino-terminal cysteine-rich region II of PvDBP (PvDBPII) has been considered as an attractive target for vaccine-mediated immunity and has successfully completed the clinical trial Phase 1. Although this molecule is an attractive vaccine candidate against vivax malaria, there is still a question on its viability due to recent findings, suggesting that there are still some aspects which needs to be looked into further. The highly polymorphic nature of PvDBPII and strain-specific immunity due to PvDBPII allelic variation in Bc epitopes may complicate vaccine efficacy. Emergence of various blood-stage antigens, such as PvRBP, PvEBP and supposedly many more might stand in the way of attaining full protection from PvDBPII. As a result, there is an urgent need to assess and re-assess various caveats connected to PvDBP, which might help in designing a long-term promising vaccine for P. vivax malaria. This review mainly deals with a bunch of rising concerns for validation of DBPII as a vaccine candidate antigen for P. vivax malaria.
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Mittal P, Mishra S, Kar S, Pande V, Sinha A, Sharma A. Global distribution of single amino acid polymorphisms in Plasmodium vivax Duffy-binding-like domain and implications for vaccine development efforts. Open Biol 2020; 10:200180. [PMID: 32993415 PMCID: PMC7536081 DOI: 10.1098/rsob.200180] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Plasmodium vivax (Pv) malaria continues to be geographically widespread with approximately 15 million worldwide cases annually. Along with other proteins, Duffy-binding proteins (DBPs) are used by plasmodium for RBC invasion and the parasite-encoded receptor binding regions lie in their Duffy-binding-like (DBL) domains-thus making it a prime vaccine candidate. This study explores the sequence diversity in PvDBL globally, with an emphasis on India as it remains a major contributor to the global Pv malaria burden. Based on 1358 PvDBL protein sequences available in NCBI, we identified 140 polymorphic sites within 315 residues of PvDBL. Alarmingly, country-wise mapping of SAAPs from field isolates revealed varied and distinct polymorphic profiles for different nations. We report here 31 polymorphic residue positions in the global SAAP profile, most of which map to the PvDBL subdomain 2 (α1-α6). A distinct clustering of SAAPs distal to the DARC-binding sites is indicative of immune evasive strategies by the parasite. Analyses of PvDBL-neutralizing antibody complexes revealed that between 24% and 54% of interface residues are polymorphic. This work provides a framework to recce and expand the polymorphic space coverage in PvDBLs as this has direct implications for vaccine development studies. It also emphasizes the significance of surveying global SAAP distributions before or alongside the identification of vaccine candidates.
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Affiliation(s)
- Payal Mittal
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.,ICMR-National Institute of Malaria Research, New Delhi, 110077, India
| | - Siddhartha Mishra
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.,ICMR-National Institute of Malaria Research, New Delhi, 110077, India
| | - Sonalika Kar
- ICMR-National Institute of Malaria Research, New Delhi, 110077, India.,Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, 263001 India
| | - Veena Pande
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, 263001 India
| | - Abhinav Sinha
- ICMR-National Institute of Malaria Research, New Delhi, 110077, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.,ICMR-National Institute of Malaria Research, New Delhi, 110077, India
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Bahk YY, Kim J, Ahn SK, Na BK, Chai JY, Kim TS. Genetic Diversity of Plasmodium vivax Causing Epidemic Malaria in the Republic of Korea. THE KOREAN JOURNAL OF PARASITOLOGY 2018; 56:545-552. [PMID: 30630274 PMCID: PMC6327206 DOI: 10.3347/kjp.2018.56.6.545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 11/04/2018] [Accepted: 11/05/2018] [Indexed: 11/23/2022]
Abstract
Plasmodium vivax is more challenging to control and eliminate than P. falciparum due to its more asymptomatic infections with low parasite densities making diagnosis more difficult, in addition to its unique biological characteristics. The potential re-introduction of incidence cases, either through borders or via human migrations, is another major hurdle to sustained control and elimination. The Republic of Korea has experienced re-emergence of vivax malaria in 1993 but is one of the 32 malaria-eliminating countries to-date. Despite achieving successful nationwide control and elimination of vivax malaria, the evolutionary characteristics of vivax malaria isolates in the Republic of Korea have not been fully understood. In this review, we present an overview of the genetic variability of such isolates to increase understanding of the epidemiology, diversity, and dynamics of vivax populations in the Republic of Korea.
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Affiliation(s)
- Young Yil Bahk
- Department of Biotechnology, College of Biomedical and Health Science, Konkuk University, Chungju 27478,
Korea
| | - Jeonga Kim
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, UAB Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294,
USA
| | - Seong Kyu Ahn
- Department of Parasitology and Tropical Medicine, Inha University School of Medicine, Incheon 22212,
Korea
| | - Byoung-Kuk Na
- Department of Parasitology and Tropical Medicine and Institute of Health Sciences, Gyeongsang National University College of Medicine, Jinju 52727,
Korea
| | - Jong-Yil Chai
- Korea Association of Health Promotion, Seoul 07653,
Korea
| | - Tong-Soo Kim
- Department of Parasitology and Tropical Medicine, Inha University School of Medicine, Incheon 22212,
Korea
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6
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Roesch C, Popovici J, Bin S, Run V, Kim S, Ramboarina S, Rakotomalala E, Rakotoarison RL, Rasoloharimanana T, Andriamanantena Z, Kumar A, Guillotte-Blisnick M, Huon C, Serre D, Chitnis CE, Vigan-Womas I, Menard D. Genetic diversity in two Plasmodium vivax protein ligands for reticulocyte invasion. PLoS Negl Trop Dis 2018; 12:e0006555. [PMID: 30346980 PMCID: PMC6211765 DOI: 10.1371/journal.pntd.0006555] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 11/01/2018] [Accepted: 08/17/2018] [Indexed: 01/30/2023] Open
Abstract
The interaction between Plasmodium vivax Duffy binding protein (PvDBP) and Duffy antigen receptor for chemokines (DARC) has been described as critical for the invasion of human reticulocytes, although increasing reports of P. vivax infections in Duffy-negative individuals questions its unique role. To investigate the genetic diversity of the two main protein ligands for reticulocyte invasion, PvDBP and P. vivax Erythrocyte Binding Protein (PvEBP), we analyzed 458 isolates collected in Cambodia and Madagascar from individuals genotyped as Duffy-positive. First, we observed a high proportion of isolates with multiple copies PvEBP from Madagascar (56%) where Duffy negative and positive individuals coexist compared to Cambodia (19%) where Duffy-negative population is virtually absent. Whether the gene amplification observed is responsible for alternate invasion pathways remains to be tested. Second, we found that the PvEBP gene was less diverse than PvDBP gene (12 vs. 33 alleles) but provided evidence for an excess of nonsynonymous mutations with the complete absence of synonymous mutations. This finding reveals that PvEBP is under strong diversifying selection, and confirms the importance of this protein ligand in the invasion process of the human reticulocytes and as a target of acquired immunity. These observations highlight how genomic changes in parasite ligands improve the fitness of P. vivax isolates in the face of immune pressure and receptor polymorphisms.
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Affiliation(s)
- Camille Roesch
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Jean Popovici
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Sophalai Bin
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Vorleak Run
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Saorin Kim
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Stéphanie Ramboarina
- Immunology of Infectious Diseases Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | - Emma Rakotomalala
- Immunology of Infectious Diseases Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | | | | | - Zo Andriamanantena
- Immunology of Infectious Diseases Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | - Anuj Kumar
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | | | - Christèle Huon
- Malaria Parasite Biology and Vaccines Unit, Institut Pasteur, Paris, France
| | - David Serre
- Institute for Genome Sciences, University of Maryland, Baltimore, Maryland, United States of America
| | - Chetan E. Chitnis
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- Malaria Parasite Biology and Vaccines Unit, Institut Pasteur, Paris, France
- * E-mail: (CEC); (IVW); (DM)
| | - Inès Vigan-Womas
- Immunology of Infectious Diseases Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
- * E-mail: (CEC); (IVW); (DM)
| | - Didier Menard
- Malaria Molecular Epidemiology Unit, Institut Pasteur in Cambodia, Phnom Penh, Cambodia
- * E-mail: (CEC); (IVW); (DM)
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7
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Paleopathological Considerations on Malaria Infection in Korea before the 20th Century. BIOMED RESEARCH INTERNATIONAL 2018; 2018:8516785. [PMID: 29854798 PMCID: PMC5966694 DOI: 10.1155/2018/8516785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 04/01/2018] [Indexed: 12/31/2022]
Abstract
Malaria, one of the deadliest diseases in human history, still infects many people worldwide. Among the species of the genus Plasmodium, P. vivax is commonly found in temperate-zone countries including South Korea. In this article, we first review the history of malarial infection in Korea by means of studies on Joseon documents and the related scientific data on the evolutionary history of P. vivax in Asia. According to the historical records, malarial infection was not unusual in pre-20th-century Korean society. We also found that certain behaviors of the Joseon people might have affected the host-vector-pathogen relationship, which could explain why malarial infection prevalence was so high in Korea at that time. In our review of genetic studies on P. vivax, we identified substantial geographic differentiation among continents and even between neighboring countries. Based on these, we were able to formulate a strategy for future analysis of ancient Plasmodium strains in Korea.
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Xu C, Wei QK, Li J, Xiao T, Yin K, Zhao CL, Wang YB, Kong XL, Zhao GH, Sun H, Liu X, Huang BC. Characteristics of Imported Malaria and Species of Plasmodium Involved in Shandong Province, China (2012-2014). THE KOREAN JOURNAL OF PARASITOLOGY 2016; 54:407-14. [PMID: 27658591 PMCID: PMC5040091 DOI: 10.3347/kjp.2016.54.4.407] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/19/2016] [Accepted: 05/24/2016] [Indexed: 02/04/2023]
Abstract
Malaria remains a serious public health problem in Shandong Province, China; therefore, it is important to explore the characteristics of the current malaria prevalence situation in the province. In this study, data of malaria cases reported in Shandong during 2012-2014 were analyzed, and Plasmodium species were confirmed by smear microscopy and nested-PCR. A total of 374 malaria cases were reported, 80.8% of which were reported from 6 prefectures. Of all cases, P. falciparum was dominant (81.3%), followed by P. vivax (11.8%); P. ovale and P. malariae together accounted for 6.4% of cases. Notably, for the first time since 2012, no indigenous case had been reported in Shandong Province, a situation that continued through 2014. Total 95.2% of cases were imported from Africa. The ratio of male/female was 92.5:1, and 96.8% of cases occurred in people 20-54 years of age. Farmers or laborers represented 77.5% of cases. No significant trends of monthly pattern were found in the reported cases. All patients were in good condition after treatment, except for 3 who died. These results indicate that imported malaria has increased significantly since 2012 in Shandong Province, especially for P. falciparum, and there is an emergence of species diversity.
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Affiliation(s)
- Chao Xu
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Qing-Kuan Wei
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Jin Li
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Ting Xiao
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Kun Yin
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Chang-Lei Zhao
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Yong-Bin Wang
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Xiang-Li Kong
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Gui-Hua Zhao
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Hui Sun
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Xin Liu
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
| | - Bing-Cheng Huang
- Shandong Academy of Medical Sciences, Shandong Institute of Parasitic Diseases, Shandong Provincial Reference Laboratory for Malaria Diagnosis, Jining, Shandong Province 272033, People's Republic of China
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9
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Strain-Transcending Inhibitory Antibodies against Homologous and Heterologous Strains of Duffy Binding Protein region II. PLoS One 2016; 11:e0154577. [PMID: 27145131 PMCID: PMC4856259 DOI: 10.1371/journal.pone.0154577] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 04/17/2016] [Indexed: 11/22/2022] Open
Abstract
Duffy binding protein region II (DBPII) is a promising vaccine candidate against vivax malaria. However, polymorphisms of DBPII are the major obstacle to designing a successful vaccine. Here, we examined whether anti-DBPII antibodies from individual P. vivax exposures provide strain-transcending immunity and whether their presence is associated with DBPII haplotypes found in patients with acute P. vivax. The ability of antibodies to inhibit DBL-TH-erythrocyte binding was tested by COS7 erythrocyte binding inhibition assay. Seven samples of high responders (HR) were identified from screening anti-DBPII levels. HR no.3 and HR no.6 highly inhibited all DBL-TH binding to erythrocytes, by >80%. Antibodies from these two patients’ plasma had the potential to be broadly inhibitory against DBL-TH1, -TH2, -TH6, -TH7, -TH8 and -TH9 haplotypes when plasma was serially diluted from 1:500 to 1:2000. To further examine the association of DBPII haplotypes and the ability of antibodies to broadly inhibit DBL-TH variants, the individual samples underwent sequencing analysis and the inhibitory function of the anti-DBPII antibodies was tested. The patterns of DBPII polymorphisms in acute patients were classified into two groups, DBPII Sal I (55%) and DBL-TH variants (45%). Plasma from Sal I and DBPII-TH patients who had the highest inhibition against Sal I or DBL-TH4 and -TH5 was serially diluted from 1:500 to 1:2000 and their inhibitory capacity was tested against a panel of DBL-TH haplotypes. Results provided evidence of both strain-transcending inhibition as well as strain-specific inhibition by antibodies that blocked erythrocyte binding against some DBL-TH variants and against homologous alleles. This study demonstrated broad inhibition by anti-DBPII antibodies against DBL-TH haplotypes in natural P. vivax exposed individuals. The identification of conserved epitopes among DBL-TH may have implications for vaccine development of a DBPII-based vaccine against diverse P. vivax infections.
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10
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González-Cerón L, Cerritos R, Corzo-Mancilla J, Santillán F. Diversity and evolutionary genetics of the three major Plasmodium vivax merozoite genes participating in reticulocyte invasion in southern Mexico. Parasit Vectors 2015; 8:651. [PMID: 26691669 PMCID: PMC4687067 DOI: 10.1186/s13071-015-1266-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 12/11/2015] [Indexed: 11/25/2022] Open
Abstract
Background Reported malaria cases in the Americas had been reduced to about one-half million by 2012. To advance towards elimination of this disease, it is necessary to gain insights into how the malaria parasite is evolving, including the emergence, spread and persistence of new haplotypes in affected regions. In here, the genetic diversity of the three major P. vivax merozoite genes was analyzed. Methods From P. vivax-infected blood samples obtained in southern Mexico (SMX) during 2006–2007, nucleotide sequences were achieved for: the 42 kDa carboxyl fragment of the merozoite surface protein-1 (msp142), domains I-II of the apical membrane antigen-1 (ama1I-II), and domain II of the Duffy binding protein (dbpII). Gene polymorphism was examined and haplotype networks were developed to depict parasite relationships in SMX. Then genetic diversity, recombination and natural selection were analyzed and the degree of differentiation was determined as FST values. Results The diversity of P. vivax merozoite genes in SMX was less than that of parasites from other geographic origins, with dbpII < ama1I-II < msp142. Ama1I-II and msp142 exposed the more numerous haplotypes exclusive to SMX. While, all dbpII haplotypes from SMX were separated from one to three mutational steps, the networks of ama1I-II and msp142 were more complex; loops and numerous mutational steps were evidenced, likely due to recombination. Sings of local diversification were more evident for msp142. Sixteen combined haplotypes were determined; one of these haplotypes not detected in 2006 was highly frequent in 2007. The Rm value was higher for msp142than for ama1I-II, being insignificant for dbpII. The dN-dS value was highly significant for ama1I-II and lesser so for dbpII. The FST values were higher for dbpII than msp142, and very low for ama1I-II. Conclusions In SMX, P. vivax ama1I-II, dbpII and msp142 demonstrated limited diversity, and exhibited a differentiated parasite population. The results suggest that differential intensities of selective forces are operating on these gene fragments, and probably related to their timing, length of exposure and function during reticulocyte adhesion and invasion. Therefore, these finding are essential for mono and multivalent vaccine development and for epidemiological surveillance. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1266-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lilia González-Cerón
- Regional Centre for Research in Public Health, National Institute for Public Health, Tapachula, Chiapas, 30700, Mexico.
| | - Rene Cerritos
- Departamento de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, México, DF, 04510, México.
| | - Jordán Corzo-Mancilla
- Regional Centre for Research in Public Health, National Institute for Public Health, Tapachula, Chiapas, 30700, Mexico.
| | - Frida Santillán
- Regional Centre for Research in Public Health, National Institute for Public Health, Tapachula, Chiapas, 30700, Mexico.
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Valizadeh V, Zakeri S, Mehrizi AA, Djadid ND. Non-allele specific antibody responses to genetically distinct variant forms of Plasmodium vivax Duffy binding protein (PvDBP-II) in Iranians exposed to seasonal malaria transmission. Acta Trop 2014; 136:89-100. [PMID: 24704284 DOI: 10.1016/j.actatropica.2014.03.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Revised: 03/17/2014] [Accepted: 03/24/2014] [Indexed: 10/25/2022]
Abstract
Duffy binding protein (DBP) is a leading vaccine candidate of Plasmodium vivax. The binding domain of DBP (DBP-II) is polymorphic, that may be a major challenge for development of a broadly effective vaccine against vivax malaria. The present investigation was undertaken to explore whether the sequence diversity of DBP-II causes variation in naturally acquired anti-DBP-II antibodies. In this study, the five genetically distinct variants were expressed, and anti-DBP-II responses were measured in P. vivax-infected individuals (n=202). Finally, by performing immune-depletion ELISA experiments, antibody responses to the conserved sites of all allelic forms were evaluated using the corresponding and non-corresponding patients' sera (n=20). In this study, natural P. vivax infection produces IgG against all five examined variant forms of PvDBP-II with no statistically difference. Sequence analysis in the 20 selected samples (for antibody depletion experiment) showed eight distinct haplotypes, DBPI (n=1), DBPIII (n=3), DBPIV (n=1), DBPV (n=1), DBPVI (n=5), DBPIX (n=6), DBPX (n=1), and DBP XI (n=2). The results showed the presence of the cross-reactive antibody responses to heterologous variants of PvDBP-II in Iranian individuals who were infected with distinct allelic forms of the PvDBP-II. Therefore, it is proposed that the majority of antibodies recognized sharing B-cell epitopes and this could overcome the PvDBP-II variation as a one of the biggest challenges of PvDBP-II-based vaccine development.
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12
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de Sousa TN, Kano FS, de Brito CFA, Carvalho LH. The Duffy binding protein as a key target for a Plasmodium vivax vaccine: lessons from the Brazilian Amazon. Mem Inst Oswaldo Cruz 2014; 109:608-17. [PMID: 25185002 PMCID: PMC4156454 DOI: 10.1590/0074-0276130592] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 03/11/2014] [Indexed: 11/21/2022] Open
Abstract
Plasmodium vivax infects human erythrocytes through a major pathway that requires interaction between an apical parasite protein, the Duffy binding protein (PvDBP) and its receptor on reticulocytes, the Duffy antigen/receptor for chemokines (DARC). The importance of the interaction between PvDBP (region II, DBPII) and DARC to P. vivax infection has motivated our malaria research group at Oswaldo Cruz Foundation (state of Minas Gerais, Brazil) to conduct a number of immunoepidemiological studies to characterise the naturally acquired immunity to PvDBP in populations living in the Amazon rainforest. In this review, we provide an update on the immunology and molecular epidemiology of PvDBP in the Brazilian Amazon - an area of markedly unstable malaria transmission - and compare it with data from other parts of Latin America, as well as Asia and Oceania.
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Genetic diversity, haplotypes and allele groups of Duffy binding protein (PkDBPαII) of Plasmodium knowlesi clinical isolates from Peninsular Malaysia. Parasit Vectors 2014; 7:161. [PMID: 24693997 PMCID: PMC4022242 DOI: 10.1186/1756-3305-7-161] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/31/2014] [Indexed: 11/10/2022] Open
Abstract
Background The monkey malaria parasite Plasmodium knowlesi is now recognized as the fifth species of Plasmodium that can cause human malaria. Like the region II of the Duffy binding protein of P. vivax (PvDBPII), the region II of the P. knowlesi Duffy binding protein (PkDBPαII) plays an essential role in the parasite’s invasion into the host’s erythrocyte. Numerous polymorphism studies have been carried out on PvDBPII, but none has been reported on PkDBPαII. In this study, the genetic diversity, haplotyes and allele groups of PkDBPαII of P. knowlesi clinical isolates from Peninsular Malaysia were investigated. Methods Blood samples from 20 knowlesi malaria patients and 2 wild monkeys (Macaca fascicularis) were used. These samples were collected between 2010 and 2012. The PkDBPαII region of the isolates was amplified by PCR, cloned into Escherichia coli, and sequenced. The genetic diversity, natural selection and haplotypes of PkDBPαII were analysed using MEGA5 and DnaSP ver. 5.10.00 programmes. Results Fifty-three PkDBPαII sequences from human infections and 6 from monkeys were obtained. Comparison at the nucleotide level against P. knowlesi strain H as reference sequence showed 52 synonymous and 76 nonsynonymous mutations. Analysis on the rate of these mutations indicated that PkDBPαII was under purifying (negative) selection. At the amino acid level, 36 different PkDBPαII haplotypes were identified. Twelve of the 20 human and 1 monkey blood samples had mixed haplotype infections. These haplotypes were clustered into 2 distinct allele groups. The majority of the haplotypes clustered into the large dominant group. Conclusions Our present study is the first to report the genetic diversity and natural selection of PkDBPαII. Hence, the haplotypes described in this report can be considered as novel. Although a high level of genetic diversity was observed, the PkDBPαII appeared to be under purifying selection. The distribution of the haplotypes was skewed, with one dominant major and one minor group. Future study should investigate PkDBPαII of P. knowlesi from Borneo, which hitherto has recorded the highest number of human knowlesi malaria.
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Valizadeh V, Zakeri S, Mehrizi AA, Djadid ND. Population genetics and natural selection in the gene encoding the Duffy binding protein II in Iranian Plasmodium vivax wild isolates. INFECTION GENETICS AND EVOLUTION 2013; 21:424-35. [PMID: 24384095 DOI: 10.1016/j.meegid.2013.12.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 12/20/2013] [Accepted: 12/21/2013] [Indexed: 10/25/2022]
Abstract
Region II of Duffy binding protein (PvDBP-II) is one of the most promising blood-stage vaccine candidate antigens against Plasmodium vivax and having knowledge of the nature and genetic polymorphism of PvDBP-II among global P. vivax isolates is important for developing a DBP-based vaccine. By using PCR and sequencing, the present molecular population genetic approach was carried out to investigate sequence diversity and natural selection of dbp-II gene in 63 P. vivax isolates collected from unstable and low transmission malaria-endemic areas of Iran during 2008-2012. Also, phylogenetic analysis, the diversifying natural selection, and recombination across the pvdbp-II gene, including regions containing B-cell epitopes were analyzed using the DnaSP and MEGA4 programs. Twenty two single nucleotide polymorphisms (SNPs, including 20 non-synonymous and 2 synonymous) were identified in PvDBP-II, resulting in 16 different PvDBP-II haplotypes among the Iranian P. vivax isolates. High binding inhibitory B-cell epitope (H3) overlapping with intrinsically unstructured/disordered region (aa: 384-392) appeared to be highly polymorphic (D384G/E385K/ K386N/Q/R390H), and positive selective pressure acted on this region. Most of the polymorphic amino acids, which are located on the surface of the protein, are under selective pressure that implies increased recombination events and exposure to the human immune system. In summary, PvDBP-II gene displays genetic polymorphism among Iranian P. vivax isolates and it is under selective pressure. Mutations, recombination, and positive selection seem to play a role in the resulting genetic diversity, and phylogenetic analysis of DNA sequences demonstrates that Iranian isolates represent a sample of the global population. These results are useful for understanding the nature of the P. vivax population in Iran and also for development of PvDBP-II-based malaria vaccine.
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Affiliation(s)
- Vahideh Valizadeh
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran.
| | - Akram Abouie Mehrizi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
| | - Navid Dinparast Djadid
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran
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Iwagami M, Hwang SY, Kim SH, Park SJ, Lee GY, Matsumoto-Takahashi ELA, Kho WG, Kano S. Microsatellite DNA analysis revealed a drastic genetic change of Plasmodium vivax population in the Republic of Korea during 2002 and 2003. PLoS Negl Trop Dis 2013; 7:e2522. [PMID: 24205429 PMCID: PMC3814342 DOI: 10.1371/journal.pntd.0002522] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 09/24/2013] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Vivax malaria was successfully eliminated in the Republic of Korea (South Korea) in the late 1970s, but it was found to have re-emerged from 1993. In order to control malaria and evaluate the effectiveness of malaria controls, it is important to develop a spatiotemporal understanding of the genetic structure of the parasite population. Here, we estimated the population structure and temporal dynamics of the transmission of Plasmodium vivax in South Korea by analyzing microsatellite DNA markers of the parasite. METHODOLOGY/PRINCIPAL FINDINGS We analyzed 14 microsatellite DNA loci of the P. vivax genome from 163 South Korean isolates collected from 1994 to 2008. Allelic data were used to analyze linkage disequilibrium (LD), genetic differentiation and population structure, in order to make a detailed estimate of temporal change in the parasite population. The LD analysis showed a gradual decrease in LD levels, while the levels of genetic differentiation between successive years and analysis of the population structure based on the Bayesian approach suggested that a drastic genetic change occurred in the South Korean population during 2002 and 2003. CONCLUSIONS/SIGNIFICANCE Although relapse and asymptomatic parasite carriage might influence the population structure to some extent, our results suggested the continual introduction of P. vivax into South Korea through other parasite population sources. One possible source, particularly during 2002 and 2003, is North Korea. Molecular epidemiology using microsatellite DNA of the P. vivax population is effective for assessing the population structure and temporal dynamics of parasite transmission; information that can assist in the elimination of vivax malaria in endemic areas.
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Affiliation(s)
- Moritoshi Iwagami
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Seung-Young Hwang
- Department of Parasitology, Inje University College of Medicine, Busanjin-gu, Busan, Korea
| | - So-Hee Kim
- Department of Infectious Disease and Malaria, Paik Institute of Clinical Research, Inje University, Busanjin-gu, Busan, Korea
| | - So-Jung Park
- Department of Infectious Disease and Malaria, Paik Institute of Clinical Research, Inje University, Busanjin-gu, Busan, Korea
| | - Ga-Young Lee
- Department of Parasitology, Inje University College of Medicine, Busanjin-gu, Busan, Korea
| | - Emilie Louise Akiko Matsumoto-Takahashi
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
- Department of Community and Global Health, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Weon-Gyu Kho
- Department of Parasitology, Inje University College of Medicine, Busanjin-gu, Busan, Korea
- Department of Infectious Disease and Malaria, Paik Institute of Clinical Research, Inje University, Busanjin-gu, Busan, Korea
| | - Shigeyuki Kano
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
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Genetic diversity and natural selection of Duffy binding protein of Plasmodium vivax Korean isolates. Acta Trop 2013; 125:67-74. [PMID: 23031445 DOI: 10.1016/j.actatropica.2012.09.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 09/19/2012] [Accepted: 09/22/2012] [Indexed: 11/23/2022]
Abstract
Plasmodium vivax Duffy binding protein (PvDBP) is a micronemal type I membrane protein that plays an essential role in erythrocyte invasion of merozoites. PvDBP is a prime blood stage vaccine candidate antigen against P. vivax, but its polymorphic nature represents a major obstacle to the successful design of a protective vaccine against vivax malaria. In this study, we analyzed the genetic polymorphism and natural selection at the N-terminal cysteine-rich region of PvDBP (PvDBPII) among 70 P. vivax isolates collected from Korean patients during 2005-2010. Seventeen single nucleotide polymorphisms (SNP), which resulted in 14 non-synonymous and 3 synonymous mutations, were found in PvDBPII among the Korean P. vivax isolates. Sequence analyses revealed that 13 different PvDBPII haplotypes, which were clustered into 3 distinct clades, were identified in Korean P. vivax isolates. The difference between the rates of nonsynomyous and synonymous mutations suggested that the region has evolved under natural selection. High selective pressure preferentially acted on regions identified or predicted to be B- and T-cell epitopes and MHC binding regions of PvDBPII. Recombination may also contribute to genetic diversity of PvDBPII. Our results suggest that PvDBPII of Korean P. vivax isolates display a limited genetic polymorphism and are under selective pressure. These results have significant implications for understanding the nature of the P. vivax population circulating in Korea and provide useful information for development of malaria vaccines based on this antigen.
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Chootong P, Panichakul T, Permmongkol C, Barnes SJ, Udomsangpetch R, Adams JH. Characterization of inhibitory anti-Duffy binding protein II immunity: approach to Plasmodium vivax vaccine development in Thailand. PLoS One 2012; 7:e35769. [PMID: 22558221 PMCID: PMC3338783 DOI: 10.1371/journal.pone.0035769] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 03/25/2012] [Indexed: 11/19/2022] Open
Abstract
Plasmodium vivax Duffy binding protein region II (DBPII) is an important vaccine candidate for antibody-mediated immunity against vivax malaria. A significant challenge for vaccine development of DBPII is its highly polymorphic nature that alters sensitivity to neutralizing antibody responses. Here, we aim to characterize naturally-acquired neutralizing antibodies against DBPII in individual Thai residents to give insight into P. vivax vaccine development in Thailand. Anti-DBPII IgG significantly increased in acute vivax infections compared to uninfected residents and naive controls. Antibody titers and functional anti-DBPII inhibition varied widely and there was no association between titer and inhibition activity. Most high titer plasmas had only a moderate to no functional inhibitory effect on DBP binding to erythrocytes, indicating the protective immunity against DBPII binding is strain specific. Only 5 of 54 samples were highly inhibitory against DBP erythrocyte-binding function. Previously identified target epitopes of inhibitory anti-DBPPII IgG (H1, H2 and H3) were localized to the dimer interface that forms the DARC binding pocket. Amino acid polymorphisms (monomorphic or dimorphic) in H1 and H3 protective epitopes change sensitivity of immune inhibition by alteration of neutralizing antibody recognition. The present study indicates Thai variant H1.T1 (R308S), H3.T1 (D384G) and H3.T3 (K386N) are the most important variants for a DBPII candidate vaccine needed to protect P. vivax in Thai residents.
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MESH Headings
- Adult
- Amino Acid Sequence
- Antibodies, Neutralizing/biosynthesis
- Antibodies, Neutralizing/immunology
- Antibodies, Protozoan/biosynthesis
- Antibodies, Protozoan/immunology
- Antigens, Protozoan/immunology
- Antigens, Protozoan/metabolism
- Erythrocytes/immunology
- Erythrocytes/metabolism
- Erythrocytes/parasitology
- Humans
- Malaria, Vivax/immunology
- Malaria, Vivax/parasitology
- Middle Aged
- Molecular Sequence Data
- Plasmodium vivax/immunology
- Plasmodium vivax/pathogenicity
- Polymorphism, Genetic
- Protein Structure, Tertiary
- Protozoan Proteins/antagonists & inhibitors
- Protozoan Proteins/immunology
- Protozoan Proteins/metabolism
- Receptors, Cell Surface/antagonists & inhibitors
- Receptors, Cell Surface/immunology
- Receptors, Cell Surface/metabolism
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Thailand
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Affiliation(s)
- Patchanee Chootong
- Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand.
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Iwagami M, Fukumoto M, Hwang SY, Kim SH, Kho WG, Kano S. Population structure and transmission dynamics of Plasmodium vivax in the Republic of Korea based on microsatellite DNA analysis. PLoS Negl Trop Dis 2012; 6:e1592. [PMID: 22509416 PMCID: PMC3317904 DOI: 10.1371/journal.pntd.0001592] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 02/17/2012] [Indexed: 11/19/2022] Open
Abstract
Background In order to control malaria, it is important to understand the genetic structure of the parasites in each endemic area. Plasmodium vivax is widely distributed in the tropical to temperate regions of Asia and South America, but effective strategies for its elimination have yet to be designed. In South Korea, for example, indigenous vivax malaria was eliminated by the late 1970s, but re-emerged from 1993. We estimated the population structure and temporal dynamics of transmission of P. vivax in South Korea using microsatellite DNA markers. Methodology/Principal Findings We analyzed 255 South Korean P. vivax isolates collected from 1994 to 2008, based on 10 highly polymorphic microsatellite DNA loci of the P. vivax genome. Allelic data were obtained for the 87 isolates and their microsatellite haplotypes were determined based on a combination of allelic data of the loci. In total, 40 haplotypes were observed. There were two predominant haplotypes: H16 and H25. H16 was observed in 9 isolates (10%) from 1996 to 2005, and H25 in 27 (31%) from 1995 to 2003. These results suggested that the recombination rate of P. vivax in South Korea, a temperate country, was lower than in tropical areas where identical haplotypes were rarely seen in the following year. Next, we estimated the relationships among the 40 haplotypes by eBURST analysis. Two major groups were found: one composed of 36 isolates (41%) including H25; the other of 20 isolates (23%) including H16. Despite the low recombination rate, other new haplotypes that are genetically distinct from the 2 groups have also been observed since 1997 (H27). Conclusions/Significance These results suggested a continual introduction of P. vivax from other population sources, probably North Korea. Molecular epidemiology using microsatellite DNA of the P. vivax population is effective for assessing the population structure and transmission dynamics of the parasites - information that can assist in the elimination of vivax malaria in endemic areas. Vivax malaria is widely prevalent, mainly in Asia and South America with 390 million reported cases in 2009. Worldwide, in the same year, 2.85 billion people were at risk. Plasmodium vivax is prevalent not only in tropical and subtropical areas but also in temperate areas where there are no mosquitoes in cold seasons. While most malaria researchers are focusing their studies on the parasite in tropical areas, we examined the characteristics of P. vivax in South Korea (temperate area) temporally, using 10 highly polymorphic microsatellite DNA (a short tandem repeat DNA sequence) in the parasite genome, and highlighted the differences between the tropical and temperate populations. We found that the South Korean P. vivax population had low genetic diversity and low recombination rates in comparison to tropical P. vivax populations that had been reported. We also found that some of the parasite clones in the population were changing from 1994 to 2008, evidence suggesting the continual introduction of the parasite from other populations, probably from North Korea. Polymorphic DNA markers of the P. vivax parasite are useful tools for estimating the situation of its transmission in endemic areas.
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Affiliation(s)
- Moritoshi Iwagami
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
| | - Megumi Fukumoto
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Seung-Young Hwang
- Department of Parasitology, College of Medicine, Inje University, Busanjin-gu, Busan, Korea
| | - So-Hee Kim
- Department of Malariology, College of Medicine, Paik Institute of Clinical Research, Inje University, Busanjin-gu, Busan, Korea
| | - Weon-Gyu Kho
- Department of Parasitology, College of Medicine, Inje University, Busanjin-gu, Busan, Korea
- Department of Malariology, College of Medicine, Paik Institute of Clinical Research, Inje University, Busanjin-gu, Busan, Korea
- * E-mail: (WGK); (SK)
| | - Shigeyuki Kano
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
- * E-mail: (WGK); (SK)
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Ju HL, Kang JM, Moon SU, Kim JY, Lee HW, Lin K, Sohn WM, Lee JS, Kim TS, Na BK. Genetic polymorphism and natural selection of Duffy binding protein of Plasmodium vivax Myanmar isolates. Malar J 2012; 11:60. [PMID: 22380592 PMCID: PMC3358247 DOI: 10.1186/1475-2875-11-60] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 03/01/2012] [Indexed: 11/27/2022] Open
Abstract
Background Plasmodium vivax Duffy binding protein (PvDBP) plays an essential role in erythrocyte invasion and a potential asexual blood stage vaccine candidate antigen against P. vivax. The polymorphic nature of PvDBP, particularly amino terminal cysteine-rich region (PvDBPII), represents a major impediment to the successful design of a protective vaccine against vivax malaria. In this study, the genetic polymorphism and natural selection at PvDBPII among Myanmar P. vivax isolates were analysed. Methods Fifty-four P. vivax infected blood samples collected from patients in Myanmar were used. The region flanking PvDBPII was amplified by PCR, cloned into Escherichia coli, and sequenced. The polymorphic characters and natural selection of the region were analysed using the DnaSP and MEGA4 programs. Results Thirty-two point mutations (28 non-synonymous and four synonymous mutations) were identified in PvDBPII among the Myanmar P. vivax isolates. Sequence analyses revealed that 12 different PvDBPII haplotypes were identified in Myanmar P. vivax isolates and that the region has evolved under positive natural selection. High selective pressure preferentially acted on regions identified as B- and T-cell epitopes of PvDBPII. Recombination may also be played a role in the resulting genetic diversity of PvDBPII. Conclusions PvDBPII of Myanmar P. vivax isolates displays a high level of genetic polymorphism and is under selective pressure. Myanmar P. vivax isolates share distinct types of PvDBPII alleles that are different from those of other geographical areas. These results will be useful for understanding the nature of the P. vivax population in Myanmar and for development of PvDBPII-based vaccine.
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Affiliation(s)
- Hye-Lim Ju
- Department of Parasitology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Korea
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Brito CFAD, Ferreira MU. Molecular markers and genetic diversity of Plasmodium vivax. Mem Inst Oswaldo Cruz 2012; 106 Suppl 1:12-26. [PMID: 21881753 DOI: 10.1590/s0074-02762011000900003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 06/08/2011] [Indexed: 11/22/2022] Open
Abstract
Enhanced understanding of the transmission dynamics and population genetics for Plasmodium vivax is crucial in predicting the emergence and spread of novel parasite phenotypes with major public health implications, such as new relapsing patterns, drug resistance and increased virulence. Suitable molecular markers are required for these population genetic studies. Here, we focus on two groups of molecular markers that are commonly used to analyse natural populations of P. vivax. We use markers under selective pressure, for instance, antigen-coding polymorphic genes, and markers that are not under strong natural selection, such as most minisatellite and microsatellite loci. First, we review data obtained using genes encoding for P. vivax antigens: circumsporozoite protein, merozoite surface proteins 1 and 3α, apical membrane antigen 1 and Duffy binding antigen. We next address neutral or nearly neutral molecular markers, especially microsatellite loci, providing a complete list of markers that have already been used in P. vivax populations studies. We also analyse the microsatellite loci identified in the P. vivax genome project. Finally, we discuss some practical uses for P. vivax genotyping, for example, detecting multiple-clone infections and tracking the geographic origin of isolates.
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Honma H, Kim JY, Palacpac NMQ, Mita T, Lee W, Horii T, Tanabe K. Recent increase of genetic diversity in Plasmodium vivax population in the Republic of Korea. Malar J 2011; 10:257. [PMID: 21899730 PMCID: PMC3176257 DOI: 10.1186/1475-2875-10-257] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 09/07/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The reemergence of Plasmodium vivax in South Korea since 1993 represents a serious public health concern. Despite the importance in understanding genetic diversity for control strategies, however, studies remain inconclusive with the general premise that due to low rate of malaria transmission, there is generally low genetic diversity with very few strains involved. In this study, the genetic diversity and population structure of P. vivax in South Korea were explored by analysing microsatellite polymorphism. METHODS Sequences for 13 microsatellite loci distributed across the twelve chromosomes of P. vivax were obtained from 58 South Korean isolates collected during two sampling periods, namely 1997-2000 and 2007. The sequences were used for the analysis of expected heterozygosity and multilocus genotype diversity. Population structure was evaluated using STRUCTURE version 2.3.2. Linkage disequilibrium was also analysed to investigate the extent of outbreeding in the P. vivax population. RESULTS Mean expected heterozygosity significantly increased from 0.382 in 1997-2000 to 0.545 in 2007 (P < 0.05). The number of multilocus genotypes was 7 and 27; and genotype diversity was statistically significant (P < 0.01) at 0.661 and 0.995 in 1997-2000 and 2007, respectively. Analysis by STRUCTURE showed a more complex population structure in 2007 than in 1997-2000. Linkage disequilibrium between 13 microsatellites, although significant in both time points, was notably lower in 2007. CONCLUSIONS The present microsatellite analysis clearly showed recent increase of genetic diversity and recent relaxation of the strong population structure observed in 1997-2000. These results suggest that multiple genotypes not present previously recently migrated into South Korea, accompanied by substantial outbreeding between different genotypes.
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Affiliation(s)
- Hajime Honma
- Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
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22
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Zakeri S, Babaeekhou L, Mehrizi AA, Abbasi M, Djadid ND. Antibody responses and avidity of naturally acquired anti-Plasmodium vivax Duffy binding protein (PvDBP) antibodies in individuals from an area with unstable malaria transmission. Am J Trop Med Hyg 2011; 84:944-50. [PMID: 21633032 DOI: 10.4269/ajtmh.2011.11-0001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Plasmodium vivax remains an important cause of morbidity outside Africa, and no effective vaccine is available against this parasite. The P. vivax Duffy binding protein (PvDBP) is essential during merozoite invasion into erythrocytes, and it is a target for protective immunity against malaria. This investigation was designed to evaluate naturally acquired antibodies to two variant forms of PvDBP-II antigen (DBP-I and -VI) in malaria individuals (N = 85; median = 22 years) who were living in hypoendemic areas in Iran. The two PvDBP-II variants were expressed in Escherichia coli, and immunoglobulin G (IgG) isotype composition and avidity of naturally acquired antibodies to these antigens were measured using enzyme-linked immunosorbent assay (ELISA). Results showed that almost 32% of the studied individuals had positive antibody responses to the two PvDBP-II variants, and the prevalence of responders did not differ significantly (P > 0.05; χ(2) test). The IgG-positive samples exhibited 37.03% and 40.8% high-avidity antibodies for PvDBP-I and PvDBP-VI variants, respectively. Furthermore, high-avidity IgG1 antibody was found in 39.1% of positive sera for each examined variant antigen. The avidity of antibodies for both PvDBP variant antigens and the prevalence of responders with high- and intermediate-avidity IgG, IgG1, and IgG3 antibodies were similar in patients (P > 0.05; χ(2) test). Moreover, the prevalence of IgG antibody responses to the two variants significantly increased with exposure and host age. To sum up, the results provided additional data in our understanding of blood-stage immunity to PvDBP, supporting the rational development of an effective blood-stage vaccine based on this antigen.
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Affiliation(s)
- Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran.
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23
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Nóbrega de Sousa T, Carvalho LH, Alves de Brito CF. Worldwide genetic variability of the Duffy binding protein: insights into Plasmodium vivax vaccine development. PLoS One 2011; 6:e22944. [PMID: 21829672 PMCID: PMC3149059 DOI: 10.1371/journal.pone.0022944] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 07/08/2011] [Indexed: 11/19/2022] Open
Abstract
The dependence of Plasmodium vivax on invasion mediated by Duffy binding protein (DBP) makes this protein a prime candidate for development of a vaccine. However, the development of a DBP-based vaccine might be hampered by the high variability of the protein ligand (DBPII), known to bias the immune response toward a specific DBP variant. Here, the hypothesis being investigated is that the analysis of the worldwide DBPII sequences will allow us to determine the minimum number of haplotypes (MNH) to be included in a DBP-based vaccine of broad coverage. For that, all DBPII sequences available were compiled and MNH was based on the most frequent nonsynonymous single nucleotide polymorphisms, the majority mapped on B and T cell epitopes. A preliminary analysis of DBPII genetic diversity from eight malaria-endemic countries estimated that a number between two to six DBP haplotypes (17 in total) would target at least 50% of parasite population circulating in each endemic region. Aiming to avoid region-specific haplotypes, we next analyzed the MNH that broadly cover worldwide parasite population. The results demonstrated that seven haplotypes would be required to cover around 60% of DBPII sequences available. Trying to validate these selected haplotypes per country, we found that five out of the eight countries will be covered by the MNH (67% of parasite populations, range 48–84%). In addition, to identify related subgroups of DBPII sequences we used a Bayesian clustering algorithm. The algorithm grouped all DBPII sequences in six populations that were independent of geographic origin, with ancestral populations present in different proportions in each country. In conclusion, in this first attempt to undertake a global analysis about DBPII variability, the results suggest that the development of DBP-based vaccine should consider multi-haplotype strategies; otherwise a putative P. vivax vaccine may not target some parasite populations.
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Affiliation(s)
- Taís Nóbrega de Sousa
- Laboratory of Malaria, Centro de Pesquisa Rene Rachou/Fiocruz, Belo Horizonte, Brazil
| | - Luzia Helena Carvalho
- Laboratory of Malaria, Centro de Pesquisa Rene Rachou/Fiocruz, Belo Horizonte, Brazil
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24
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McHenry AM, Barnes SJ, Ntumngia FB, King CL, Adams JH. Determination of the molecular basis for a limited dimorphism, N417K, in the Plasmodium vivax Duffy-binding protein. PLoS One 2011; 6:e20192. [PMID: 21629662 PMCID: PMC3101244 DOI: 10.1371/journal.pone.0020192] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 04/20/2011] [Indexed: 11/19/2022] Open
Abstract
Invasion of human red blood cells by Plasmodium merozoites is vital for replication and survival of the parasite and, as such, is an attractive target for therapeutic intervention. Merozoite invasion is mediated by specific interactions between parasite ligands and host erythrocyte receptors. The P. vivax Duffy-binding protein (PvDBP) is heavily dependent on the interaction with the human Duffy blood group antigen/receptor for chemokines (DARC) for invasion. Region II of PvDBP contains many allelic polymorphisms likely to have arisen by host immune selection. Successful vaccine development necessitates a deeper understanding of the role of these polymorphisms in both parasite function and evasion of host immunity. A 3D structure of the homologous P. knowlesi DBP predicts that most variant residues are surface-exposed, including N417K, which is a dimorphic residue change that has previously been shown to be part of a linked haplotype that alters DBP sensitivity to inhibitory antibody. In natural isolates only two residues are found at this site, asparagine (N) and lysine (K). Site-directed mutagenesis of residue 417 was used to create a panel of 20 amino acid variants that were then examined for their binding phenotype and response to immune sera. Our results suggest that the observed dimorphism likely arose due to both structural requirements and immune selection pressure. To our knowledge, this is the first exhaustive examination of this kind of the role of a single amino acid residue in antigenic character and binding ability. Our results demonstrate that a single amino acid substitution can dramatically alter both the ability of the PvDBP to bind to human erythrocytes and its antigenic character.
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Affiliation(s)
- Amy M. McHenry
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America
- Department of Global Health, University of South Florida, Tampa, Florida, United States of America
| | - Samantha J. Barnes
- Department of Global Health, University of South Florida, Tampa, Florida, United States of America
- Department of Epidemiology and Biostatistics, University of South Florida, Tampa, Florida, United States of America
| | - Francis B. Ntumngia
- Department of Global Health, University of South Florida, Tampa, Florida, United States of America
| | - Christopher L. King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - John H. Adams
- Department of Global Health, University of South Florida, Tampa, Florida, United States of America
- * E-mail:
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25
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Sousa TN, Tarazona-Santos EM, Wilson DJ, Madureira AP, Falcão PRK, Fontes CJF, Gil LHS, Ferreira MU, Carvalho LH, Brito CFA. Genetic variability and natural selection at the ligand domain of the Duffy binding protein in Brazilian Plasmodium vivax populations. Malar J 2010; 9:334. [PMID: 21092207 PMCID: PMC3003673 DOI: 10.1186/1475-2875-9-334] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 11/22/2010] [Indexed: 11/30/2022] Open
Abstract
Background Plasmodium vivax malaria is a major public health challenge in Latin America, Asia and Oceania, with 130-435 million clinical cases per year worldwide. Invasion of host blood cells by P. vivax mainly depends on a type I membrane protein called Duffy binding protein (PvDBP). The erythrocyte-binding motif of PvDBP is a 170 amino-acid stretch located in its cysteine-rich region II (PvDBPII), which is the most variable segment of the protein. Methods To test whether diversifying natural selection has shaped the nucleotide diversity of PvDBPII in Brazilian populations, this region was sequenced in 122 isolates from six different geographic areas. A Bayesian method was applied to test for the action of natural selection under a population genetic model that incorporates recombination. The analysis was integrated with a structural model of PvDBPII, and T- and B-cell epitopes were localized on the 3-D structure. Results The results suggest that: (i) recombination plays an important role in determining the haplotype structure of PvDBPII, and (ii) PvDBPII appears to contain neutrally evolving codons as well as codons evolving under natural selection. Diversifying selection preferentially acts on sites identified as epitopes, particularly on amino acid residues 417, 419, and 424, which show strong linkage disequilibrium. Conclusions This study shows that some polymorphisms of PvDBPII are present near the erythrocyte-binding domain and might serve to elude antibodies that inhibit cell invasion. Therefore, these polymorphisms should be taken into account when designing vaccines aimed at eliciting antibodies to inhibit erythrocyte invasion.
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Affiliation(s)
- Taís N Sousa
- Laboratory of Malaria, Centro de Pesquisa Rene Rachou/FIOCRUZ, Belo Horizonte, Brazil
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26
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Choi YK, Choi KM, Park MH, Lee EG, Kim YJ, Lee BC, Cho SH, Rhie HG, Lee HS, Yu JR, Lee JS, Kim TS, Kim JY. Rapid dissemination of newly introduced Plasmodium vivax genotypes in South Korea. Am J Trop Med Hyg 2010; 82:426-32. [PMID: 20207868 PMCID: PMC2829904 DOI: 10.4269/ajtmh.2010.09-0245] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Accepted: 09/28/2009] [Indexed: 11/07/2022] Open
Abstract
Reemerged Plasmodium vivax malaria in South Korea has not yet been eradicated despite continuous governmental efforts. It has rather become an endemic disease. Our study aimed to determine the genetic diversity in P. vivax merozoite surface protein-1 (PvMSP-1) and circumsporozoite protein (PvCSP) genes over an extended period after its reemergence to its current status. Sequence analysis of PvMSP-1 gene sequences from the 632 P. vivax isolates during 1996-2007 indicates that most isolates recently obtained were different from isolates obtained in the initial reemergence period. There was initially only one subtype (recombinant) present but its subtypes have varied since 2000; six MSP-1 subtypes were recently found. A similar variation was observed by CSP gene analysis; a new CSP subtype was found. Understanding genetic variation patterns of the parasite may help to analyze trends and assess extent of endemic malaria in South Korea.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Jung-Yeon Kim
- Divisions of Malaria and Parasitic Diseases, Division of Infectious Disease Surveillance, and Center for Immunology and Pathology, National Institute of Health, Korea Centers for Disease Control and Prevention, Seoul, Republic of Korea; Department of Biological Science, Inha University, Incheon, Republic of Korea; Department of Parasitology, Konkuk University, College of Medicine, Seoul, Republic of Korea; Institute of Global Environment and Department of Biology, Kyung Hee University, Seoul, Republic of Korea; Department of Parasitology, Inha University College of Medicine, Incheon, Republic of Korea
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27
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Hwang SY, Kim SH, Kho WG. Genetic characteristics of polymorphic antigenic markers among Korean isolates of Plasmodium vivax. THE KOREAN JOURNAL OF PARASITOLOGY 2010; 47 Suppl:S51-8. [PMID: 19885335 DOI: 10.3347/kjp.2009.47.s.s51] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 09/28/2009] [Accepted: 09/28/2009] [Indexed: 11/23/2022]
Abstract
Plasmodium vivax, a protozoan malaria parasite of humans, represents a major public health concern in the Republic of Korea (= South Korea). However, little is known about the genetic properties and population structures of the P. vivax isolates circulating in South Korea. This article reviews known polymorphic genetic markers in South Korean isolates of P. vivax and briefly summarizes the current issues surrounding the gene and population structures of this parasite. The critical genetic characteristics of major antigens of the parasite, such as circumsporozoite protein (CSP), merozoite surface protein 1 (MSP-1) and MSP-3, Duffy binding protein (DBP), apical membrane antigen 1 (AMA-1), and GAM-1, are also discussed.
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Affiliation(s)
- Seung-Young Hwang
- Department of Parasitology, Inje University College of Medicine, Busan 614-735, Korea
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28
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Mapping epitopes of the Plasmodium vivax Duffy binding protein with naturally acquired inhibitory antibodies. Infect Immun 2009; 78:1089-95. [PMID: 20008533 DOI: 10.1128/iai.01036-09] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasmodium vivax Duffy binding protein (DBP) is a merozoite microneme ligand vital for blood-stage infection, which makes it an important candidate vaccine for antibody-mediated immunity against vivax malaria. A differential screen with a linear peptide array compared the reactivities of noninhibitory and inhibitory high-titer human immune sera to identify target epitopes associated with protective immunity. Naturally acquired anti-DBP-specific serologic responses observed in the residents of a region of Papua New Guinea where P. vivax is highly endemic exhibited significant changes in DBP-specific titers over time. The anti-DBP functional inhibition for each serum ranged from complete inhibition to no inhibition even for high-titer responders to the DBP, indicating that epitope specificity is important. Inhibitory immune human antibodies identified specific B-cell linear epitopes on the DBP (SalI) ligand domain that showed significant correlations with inhibitory responses. Affinity-purified naturally acquired antibodies on these epitopes inhibited the DBP erythrocyte binding function greatly, confirming the protective value of specific epitopes. These results represent an important advance in our understanding of part of blood-stage immunity to P. vivax and some of the specific targets for vaccine-elicited antibody protection.
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29
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Ceravolo IP, Sanchez BAM, Sousa TN, Guerra BM, Soares IS, Braga EM, McHenry AM, Adams JH, Brito CFA, Carvalho LH. Naturally acquired inhibitory antibodies to Plasmodium vivax Duffy binding protein are short-lived and allele-specific following a single malaria infection. Clin Exp Immunol 2009; 156:502-10. [PMID: 19438604 DOI: 10.1111/j.1365-2249.2009.03931.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The Duffy binding protein of Plasmodium vivax (DBP) is a critical adhesion ligand that participates in merozoite invasion of human Duffy-positive erythrocytes. A small outbreak of P. vivax malaria, in a village located in a non-malarious area of Brazil, offered us an opportunity to investigate the DBP immune responses among individuals who had their first and brief exposure to malaria. Thirty-three individuals participated in the five cross-sectional surveys, 15 with confirmed P. vivax infection while residing in the outbreak area (cases) and 18 who had not experienced malaria (non-cases). In the present study, we found that only 20% (three of 15) of the individuals who experienced their first P. vivax infection developed an antibody response to DBP; a secondary boosting can be achieved with a recurrent P. vivax infection. DNA sequences from primary/recurrent P. vivax samples identified a single dbp allele among the samples from the outbreak area. To investigate inhibitory antibodies to the ligand domain of the DBP (cysteine-rich region II, DBP(II)), we performed in vitro assays with mammalian cells expressing DBP(II) sequences which were homologous or not to those from the outbreak isolate. In non-immune individuals, the results of a 12-month follow-up period provided evidence that naturally acquired inhibitory antibodies to DBP(II) are short-lived and biased towards a specific allele.
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Affiliation(s)
- I P Ceravolo
- Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, FIOCRUZ, Malaria Laboratory, Belo Horizonte, MG, Brazil.
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30
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Iwagami M, Itoda I, Hwang SY, Kho WG, Kano S. Plasmodium vivax PCR genotyping of the first malaria case imported from South Korea into Japan. J Infect Chemother 2009; 15:27-33. [PMID: 19280297 DOI: 10.1007/s10156-008-0658-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Accepted: 12/04/2008] [Indexed: 10/21/2022]
Abstract
Although indigenous malaria was successfully eradicated in Japan in 1959, malaria remains one of the most important health concerns in the control of imported infectious diseases. However, in South Korea, the re-emergence of indigenous vivax malaria was reported in 1993 in the Demilitarized Zone (the border region with North Korea), from where a vivax malaria case was imported into Japan in 2002. In this study, we conducted genotyping of the circumsporozoite protein gene, the apical membrane antigen-1 gene, and the merozoite surface protein-1 gene of Plasmodium vivax in one patient, and estimated the geographical origin of the parasites. This estimate was based on the findings of previous studies, which showed the coexistence of at least two distinct genotypes of antigenic molecules of endemic P. vivax in South Korea. One genotype is similar to that of a Chinese strain CH-5, and the other is similar to that of a North Korean isolate. The results of this study showed that the DNA sequences of the patient's P. vivax parasites were similar to those of the North Korean isolate. It may even be possible in the near future for seasonally synchronized North Korean P. vivax parasites to be imported into parts of Japan and to establish breeding populations.
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Affiliation(s)
- Moritoshi Iwagami
- Department of Appropriate Technology Development and Transfer, Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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31
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Molecular genetic characterization of the merozoite surface protein 1 Gene of Plasmodium vivax from reemerging Korean isolates. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:733-8. [PMID: 19261779 DOI: 10.1128/cvi.00493-08] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Plasmodium vivax merozoite surface protein 1 (PvMSP-1) has been considered a major candidate for the development of an antimalaria vaccine, but the molecule exhibits antigenic diversity among isolates. The extent of genetic polymorphism in the region between interspecies conserved blocks 4 and 5 (ICB4 and ICB5) of the PvMSP-1 gene was analyzed for 30 Korean isolates. Two genotypes, SK-A and SK-B, were identified on the basis of amino acid substitution. Almost all the amino acid sequences of the Korean isolates were nearly identical to those of the Solomon Island isolate Solo-83 (97.8 to 99.9% similarity) and Philippine isolates Ph-79, Ph-52-2, and Ph-49 (97.3 to 99.8% similarity). Also, we report two sequences in the isolates that were characterized on the basis of restriction fragment length polymorphism (RFLP). The RFLP profiles following digestion with the DraI restriction enzyme produced two distinguishable patterns. This study might be the first report of the region between ICB4 and ICB5 of the MSP-1 gene of P. vivax in South Korea.
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32
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Kim SH, Hwang SY, Lee YS, Choi IH, Park SG, Kho WG. Single-chain antibody fragment specific for Plasmodium vivax Duffy binding protein. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2007; 14:726-31. [PMID: 17460118 PMCID: PMC1951088 DOI: 10.1128/cvi.00456-06] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phage display of single-chain variable fragment (scFv) antibodies is a powerful tool for selecting important, useful, and specific human antibodies. We constructed a library from three patients infected with Plasmodium vivax. Panning on recombinant PvRII enriched a population of scFvs that recognized region II of the P. vivax Duffy binding protein (DBP). Three clones of scFvs that reacted with PvRII were selected, and their biological functions were analyzed. These scFvs inhibited erythrocyte binding to DBP. Clone SFDBII92 had the greatest affinity (dissociation constant = 3.62 x 10(-8) M) and the greatest inhibition activity (50% inhibitory concentration approximately 2.9 microg/ml) to DBP. Thus, we demonstrated that human neutralizing antibody could be made from malaria patients using phage display and that these neutralizing scFvs should prove valuable for developing both passive and active immunization strategies based on DBP.
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Affiliation(s)
- So-Hee Kim
- Department of Malariology, Paik Institute for Clinical Research, College of Medicine, Inje University, 633-165 Gaegum-dong, Jin-gu, Busan 614-735, South Korea
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33
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Han ET, Lee DH, Park KD, Seok WS, Kim YS, Tsuboi T, Shin EH, Chai JY. Reemerging vivax malaria: changing patterns of annual incidence and control programs in the Republic of Korea. THE KOREAN JOURNAL OF PARASITOLOGY 2007; 44:285-94. [PMID: 17170570 PMCID: PMC2559126 DOI: 10.3347/kjp.2006.44.4.285] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Changing patterns of the reemerging Plasmodium vivax malaria in the Republic of Korea (South Korea) during the period 1993 to 2005 are briefly analyzed with emphasis on the control measures used and the effects of meteorological and entomological factors. Data were obtained from the Communicable Diseases Monthly Reports published by the Korea Center for Disease Control and Prevention, and webpages of World Health Organization and United Nations. Meteorological data of Kangwon-do (Province) were obtained from local weather stations. After its first reemergence in 1993, the prevalence of malaria increased exponentially, peaking in 2000, and then decreased. In total, 21,419 cases were reported between 1993 and 2005 in South Korea. In North Korea, a total of 916,225 cases were reported between 1999 and 2004. The occurrence of malaria in high risk areas of South Korea was significantly (P > 0.05) correlated with the mosquito population but not with temperature and rainfall. Control programs, including early case detection and treatment, mass chemoprophylaxis of soldiers, and international financial aids to North Korea for malaria control have been instituted. The situation of the reemerging vivax malaria in the Republic of Korea is remarkably improving during the recent years, at least in part, due to the control activities undertaken in South and North Korea.
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Affiliation(s)
- Eun-Taek Han
- Department of Parasitology, Kangwon National University College of Medicine, Chunchon, Korea
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34
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McHenry AM, Adams JH. The crystal structure of P. knowlesi DBPalpha DBL domain and its implications for immune evasion. Trends Biochem Sci 2006; 31:487-91. [PMID: 16876418 PMCID: PMC2771397 DOI: 10.1016/j.tibs.2006.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 06/15/2006] [Accepted: 07/17/2006] [Indexed: 11/22/2022]
Abstract
Plasmodium vivax invasion of human erythrocytes requires that the ligand domain of the Duffy-binding protein (DBP) recognize its cognate erythrocyte receptor, making DBP a potential target for therapy. The recently determined crystal structure of the orthologous DBP ligand domain of the closely related simian malaria parasite Plasmodium knowlesi provides insight into the molecular basis for receptor recognition and raises important questions about the mechanism of immune evasion employed by the malaria parasite.
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Affiliation(s)
- Amy M McHenry
- Department of Biological Sciences, PO Box 369, University of Notre Dame, Notre Dame, IN 46556-0369, USA
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35
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Sousa TN, Cerávolo IP, Fernandes Fontes CJ, Couto A, Carvalho LH, Brito CFA. The pattern of major polymorphisms in the Duffy binding protein ligand domain among Plasmodium vivax isolates from the Brazilian Amazon area. Mol Biochem Parasitol 2005; 146:251-4. [PMID: 16384615 DOI: 10.1016/j.molbiopara.2005.11.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Revised: 11/03/2005] [Accepted: 11/23/2005] [Indexed: 11/21/2022]
Affiliation(s)
- Taís N Sousa
- Laboratório de Malária, Centro de Pesquisas René Rachou/Fundação Oswaldo Cruz., Barro Preto, Belo Horizonte/MG., Brazil
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36
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Chung JY, Chun EH, Chun JH, Kho WG. Analysis of the Plasmodium vivax apical membrane antigen-1 gene from re-emerging Korean isolates. Parasitol Res 2003; 90:325-9. [PMID: 12690444 DOI: 10.1007/s00436-002-0777-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2002] [Accepted: 10/07/2002] [Indexed: 10/26/2022]
Abstract
Apical membrane antigen-1 is a candidate vaccine component for malaria. In the present study, we investigated the polymorphism of the Plasmodium vivax apical membrane antigen-1 gene ( PvAMA-1) in 30 Korean isolates. The polymorphic region of the PvAMA-1 gene, corresponding to nucleotides 324-735 (aa 108-245), was amplified using polymerase chain reaction followed by cloning and sequencing. Two genotypes ( SKA and SKG) were identified on the basis of amino acid substitution. These were identical to those of the Chinese isolates. The Korean isolates showed sequence variation at six positions on the basis of the sequence of the Sal1 strain. Of these, variation at position 189 (Glu/Lys) was found only in SKA. These two genotypes were related to the genotype of the circumsporozoite and Duffy binding protein of the Korean isolate. These findings suggest that two genotypes of P. vivax coexist in the endemic area and that the re-emerging parasite in Korea may be related to or have originated in East Asia.
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Affiliation(s)
- Joon-Yong Chung
- Department of Parasitology and Institute of Malariology, Inje University College of Medicine, Pusan 614-735, Republic of Korea
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37
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Cole-Tobian J, King CL. Diversity and natural selection in Plasmodium vivax Duffy binding protein gene. Mol Biochem Parasitol 2003; 127:121-32. [PMID: 12672521 DOI: 10.1016/s0166-6851(02)00327-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Plasmodium vivax Duffy binding protein (DBP) binds to the Duffy blood group antigen on the surface of erythrocytes and is essential for invasion. Natural immunity develops to this protein making it an important vaccine candidate. Genetic diversity within and between populations was compared in 100 dbp sequences from isolates obtained from Papua New Guinea, Colombia, and South Korea. The cysteine-rich region II, that contains the binding domain, has the highest diversity compared to the rest of the dbp gene and appears to be under strong selective pressure based on statistical tests comparing rates of non-synonymous (K(n)) to synonymous mutations (K(s)) among P. vivax isolates and to those of closely related species. By contrast, meiotic recombination was not found to be significant for maintaining genetic diversity. A comparison of the patterns of nucleotide diversity within dbpII to that of genes encoding homologous erythrocyte binding proteins of Plasmodium knowlesi predict critical binding residues juxtaposed to polymorphic B- and T-cell epitopes. Phylogenic analysis and measurement of nucleotide diversity between and within the different geographic populations support emergence of distinct allelic families suggestive of divergent selection of alleles between populations. Development of a P. vivax DBP-based vaccine must take into account regions of high diversity within the molecule and alleles that show distinct geographic differences.
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Affiliation(s)
- Jennifer Cole-Tobian
- Center for Global Health and Diseases at Case Western Reserve University School of Medicine and Veteran's Affairs Medical Center, 2109 Adelbert Rd, Rm W137, Cleveland, OH 44106-4983, USA
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38
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Xainli J, Baisor M, Kastens W, Bockarie M, Adams JH, King CL. Age-dependent cellular immune responses to Plasmodium vivax Duffy binding protein in humans. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:3200-7. [PMID: 12218138 DOI: 10.4049/jimmunol.169.6.3200] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Plasmodium vivax merozoite Duffy binding protein (DBP) contains a cysteine-rich region II (DBPII) that binds to the Duffy Ag receptor for chemokines on erythrocytes, which is essential for parasite invasion. Cellular immune responses to DBPII have not been reported in P. vivax endemic populations, although they may contribute to partial acquired immunity. To examine host cellular immunity to DBPII and identify major T cell epitopes, PBMCs from 107 individuals (2-68 years old) were examined for cytokine production by ELISPOT and/or ELISA to rDBP and overlapping peptides (displaced by 2 aa spanning a 170-aa region of DBPII corresponding to the critical binding motif to the Duffy Ag receptor for chemokines). In P. vivax-exposed subjects, 60 and 71% generated significant rDBP-induced IFN-gamma and IL-10 production, respectively, 11% stimulated IL-2, and IL-5 and IL-13 were not detected. Children <5 years of age had reduced levels and frequency of rDBP-induced IL-10 and IFN-gamma production compared with partially immune older children and adults (p < 0.01). Five major T cell epitopes were identified. Three of these T cell epitopes contained polymorphic residues present in the population. Peptides synthesized corresponding to these variants induced IFN-gamma and IL-10 production to one variant and little response to the other variant in the same individual. These results demonstrate age-dependent and variant-specific cellular immune responses to DBPII and implicate this molecule in partial acquired immunity to P. vivax in endemic populations.
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MESH Headings
- Adolescent
- Adult
- Age Factors
- Aged
- Aging/immunology
- Amino Acid Motifs
- Amino Acid Sequence
- Animals
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Antigens, Protozoan/metabolism
- Carrier Proteins/genetics
- Carrier Proteins/immunology
- Carrier Proteins/metabolism
- Cells, Cultured
- Child
- Child, Preschool
- Duffy Blood-Group System/metabolism
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/metabolism
- Female
- Humans
- Immunity, Cellular/genetics
- Interferon-gamma/biosynthesis
- Interleukin-10/biosynthesis
- Malaria, Vivax/blood
- Malaria, Vivax/immunology
- Malaria, Vivax/parasitology
- Male
- Middle Aged
- Molecular Sequence Data
- Plasmodium vivax/genetics
- Plasmodium vivax/immunology
- Polymorphism, Genetic/immunology
- Protein Binding/immunology
- Protozoan Proteins
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Receptors, Cell Surface/metabolism
- Recombinant Proteins/immunology
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Affiliation(s)
- Jia Xainli
- Division of Geographic Medicine, Case Western Reserve University and Veterans Affairs Medical Center, Cleveland, OH 44106, USA
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39
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Han ET, Park JH, Shin EH, Choi MH, Oh MD, Chai JY. Apical membrane antigen-1 (AMA-1) gene sequences of re-emerging Plasmodium vivax in South Korea. THE KOREAN JOURNAL OF PARASITOLOGY 2002; 40:157-62. [PMID: 12325446 PMCID: PMC2721043 DOI: 10.3347/kjp.2002.40.3.157] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Plasmodium vivax malaria re-emerged in South Korea in 1993, and epidemics continue since then. We examined genetic variation in the region encompassing the apical membrane antigen-1 (PvAMA-1) of the parasites by DNA sequencing of the 22 re-emerging P. vivax isolates. The genotype of the PvAMA-1, which was based on sequence data previously reported for the polymorphic regions, showed that two haplotypes were present at one polymorphic site. Compared with reported data, the two types, SKOR type I and type II, were similar to Chinese CH-10A and CH-05A isolates, respectively. Thus, the present study showed that two genotypes of AMA-1 genes coexist in the re-emerging Korean P. vivax.
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Affiliation(s)
- Eun-Taek Han
- Department of Parasitology, Seoul National University College of Medicine, and Institute of Endemic Diseases, Seoul National University Medical Research Center, Seoul 110-799, Korea
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40
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Kho WG, Chung JY, Hwang UW, Chun JH, Park YH, Chung WC. Analysis of polymorphic region of GAM-1 gene in Plasmodium vivax Korean isolates. THE KOREAN JOURNAL OF PARASITOLOGY 2001; 39:313-8. [PMID: 11775332 PMCID: PMC2721217 DOI: 10.3347/kjp.2001.39.4.313] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The identification, characterization and quantification of Plasmodium sp. genetic polymorphism are becoming increasingly important in the vaccine development. We investigated polymorphism of Plasmodium vivax GAM-1 (PvGAM-1) gene in 30 Korean isolates. The polymorphic region of the PvGAM-1 gene, corresponding to nt 3792-4029, was amplified using polymerase chain reaction (PCR) followed by sequencing. All of the P. vivax Korean isolates were one type of GAM-1 gene, which were identical to that of the Belem strain. It is suggested that PvGAM-1 could not be used as a genetic marker for identifying or classifying P. vivax Korean isolates. It revealed that the polymorphic pattern was acquired basically by duplication and modification or deletion event of a 33 bp-motif fragment ended by poly guanine (G) and that there were at least three complete and one partial 33 bp-motif sequences within the polymorphic region in the longest cases such as those of South Korean and Belem isolates. In addition, we clustered P. vivax isolates with parsimonious criteria on the basis of PvGAM-1 polymorphic patterns (insertion/deletion patterns).
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Affiliation(s)
- W G Kho
- Department of Parasitology and Institute of Malariology, Inje University College of Medicine, Pusan 614-735, Korea.
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