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Gangnard S, Chêne A, Dechavanne S, Srivastava A, Avril M, Smith JD, Gamain B. VAR2CSA binding phenotype has ancient origin and arose before Plasmodium falciparum crossed to humans: implications in placental malaria vaccine design. Sci Rep 2019; 9:16978. [PMID: 31740695 PMCID: PMC6861233 DOI: 10.1038/s41598-019-53334-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/24/2019] [Indexed: 11/09/2022] Open
Abstract
VAR2CSA is a leading candidate for developing a placental malaria (PM) vaccine that would protect pregnant women living in malaria endemic areas against placental infections and improve birth outcomes. Two VAR2CSA-based PM vaccines are currently under clinical trials, but it is still unclear if the use of a single VAR2CSA variant will be sufficient to induce a broad enough humoral response in humans to cross-react with genetically diverse parasite populations. Additional immuno-focusing vaccine strategies may therefore be required to identify functionally conserved antibody epitopes in VAR2CSA. We explored the possibility that conserved epitopes could exist between VAR2CSA from the chimpanzee parasite Plasmodium reichenowi and Plasmodium falciparum sequences. Making use of VAR2CSA recombinant proteins originating from both species, we showed that VAR2CSA from P. reichenowi (Pr-VAR2CSA) binds to the placental receptor CSA with high specificity and affinity. Antibodies raised against Pr-VAR2CSA were able to recognize native VAR2CSA from different P. falciparum genotypes and to inhibit the interaction between CSA and P. falciparum-infected erythrocytes expressing different VAR2CSA variants. Our work revealed the existence of cross-species inhibitory epitopes in VAR2CSA and calls for pre-clinical studies assessing the efficacy of novel VAR2CSA-based cross-species boosting regimens.
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Affiliation(s)
- Stéphane Gangnard
- Université de Paris, UMR_S1134, BIGR, INSERM, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, F-75015, Paris, France.,Laboratory of excellence GR-Ex, F-75015, Paris, France
| | - Arnaud Chêne
- Université de Paris, UMR_S1134, BIGR, INSERM, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, F-75015, Paris, France.,Laboratory of excellence GR-Ex, F-75015, Paris, France
| | - Sébastien Dechavanne
- Université de Paris, UMR_S1134, BIGR, INSERM, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, F-75015, Paris, France.,Laboratory of excellence GR-Ex, F-75015, Paris, France
| | - Anand Srivastava
- Université de Paris, UMR_S1134, BIGR, INSERM, F-75015, Paris, France.,Institut National de la Transfusion Sanguine, F-75015, Paris, France.,Laboratory of excellence GR-Ex, F-75015, Paris, France
| | - Marion Avril
- Seattle Children's Research Institute, Seattle, WA, 98109, USA
| | - Joseph D Smith
- Seattle Children's Research Institute, Seattle, WA, 98109, USA.,Department of Global Health, University of Washington, Seattle, WA, 98195, USA
| | - Benoît Gamain
- Université de Paris, UMR_S1134, BIGR, INSERM, F-75015, Paris, France. .,Institut National de la Transfusion Sanguine, F-75015, Paris, France. .,Laboratory of excellence GR-Ex, F-75015, Paris, France.
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Abstract
There have been significant decreases in malaria mortality and morbidity in the last 10-15 years, and the most advanced pre-erythrocytic malaria vaccine, RTS,S, received a positive opinion from European regulators in July 2015. However, no blood-stage vaccine has reached a phase III trial. The first part of this review summarizes the pros and cons of various assays and models that have been and will be used to predict the efficacy of blood-stage vaccines. In the second part, blood-stage vaccine candidates that showed some efficacy in human clinical trials or controlled human malaria infection models are discussed. Then, candidates under clinical investigation are described in the third part, and other novel candidates and strategies are reviewed in the last part.
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Affiliation(s)
- Kazutoyo Miura
- a Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases , National Institutes of Health , Rockville , MD , USA
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3
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Chan JA, Fowkes FJI, Beeson JG. Surface antigens of Plasmodium falciparum-infected erythrocytes as immune targets and malaria vaccine candidates. Cell Mol Life Sci 2014; 71:3633-57. [PMID: 24691798 PMCID: PMC4160571 DOI: 10.1007/s00018-014-1614-3] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 03/04/2014] [Accepted: 03/17/2014] [Indexed: 12/19/2022]
Abstract
Understanding the targets and mechanisms of human immunity to malaria caused by Plasmodium falciparum is crucial for advancing effective vaccines and developing tools for measuring immunity and exposure in populations. Acquired immunity to malaria predominantly targets the blood stage of infection when merozoites of Plasmodium spp. infect erythrocytes and replicate within them. During the intra-erythrocytic development of P. falciparum, numerous parasite-derived antigens are expressed on the surface of infected erythrocytes (IEs). These antigens enable P. falciparum-IEs to adhere in the vasculature and accumulate in multiple organs, which is a key process in the pathogenesis of disease. IE surface antigens, often referred to as variant surface antigens, are important targets of acquired protective immunity and include PfEMP1, RIFIN, STEVOR and SURFIN. These antigens are highly polymorphic and encoded by multigene families, which generate substantial antigenic diversity to mediate immune evasion. The most important immune target appears to be PfEMP1, which is a major ligand for vascular adhesion and sequestration of IEs. Studies are beginning to identify specific variants of PfEMP1 linked to disease pathogenesis that may be suitable for vaccine development, but overcoming antigenic diversity in PfEMP1 remains a major challenge. Much less is known about other surface antigens, or antigens on the surface of gametocyte-IEs, the effector mechanisms that mediate immunity, and how immunity is acquired and maintained over time; these are important topics for future research.
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Analysis of antibody induction upon immunization with distinct NTS-DBL1α-domains of PfEMP1 from rosetting Plasmodium falciparum parasites. Malar J 2013; 12:32. [PMID: 23347690 PMCID: PMC3599323 DOI: 10.1186/1475-2875-12-32] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 01/22/2013] [Indexed: 11/15/2022] Open
Abstract
Background Rosette-formation of Plasmodium falciparum parasitized erythrocytes is of importance in the development of severe malaria. The parasite-derived molecule PfEMP1 (Plasmodium falciparum erythrocyte membrane protein 1), central to rosetting, is suggested to be included in a multimeric vaccine targeting severe disease. Methods Three recombinant NTS-DBL1α-domains of PfEMP1 were generated in Escherichia coli, purified and used for immunization of rats and goats. Antibody titres were determined in ELISA assays and responses were compared in-between different individual animals and species. Reactivity with the parasites was tested in live pRBC using FACS. B-cell epitopes prediction was carried out in silico and compared to the results obtained by peptide microarray. Screening for serological cross-reactivity with heterologous NTS-DBL1α variants was carried out by ELISA, peptide array and FACS on pRBC of different laboratory strains and patient isolates. Results All three NTS-DBL1α-domains induced high titres of antibodies that were biologically active with no apparent difference between constructs covering slightly different parts of the DBL1α-sequence. The different animal species showed comparable titres of antibodies, while variations within individuals of the species could be observed. Mapping of the recognized epitopes revealed that most parts of the molecule were able to induce an antibody response with a tendency for the N and C terminal parts of the molecule for slightly higher recognition. Important differences to the epitopes predicted were found as some of the most conserved parts of the DBL1α-domain contained the main epitopes for antibody reactivity. ELISA assays and peptide microarray demonstrated substantial cross-reactivity to heterologous variants, while binding to native PfEMP1 was observed only in few combinations on the pRBC surface, underlining that mainly internal, conserved and not surface exposed parts of the DBL1α-domain are responsible for this observation. Conclusion Biologically active antibodies can be induced consistently, with high titres, in different animal species and the antibodies elicited by different constructs react with similar epitopes. Induced antibodies recognize epitopes localized in all subdomains of the DBL1α-sequence. Cross-reactivity between NTS-DBL1α-variants is common in ELISA, but rare with live pRBC emphasizing that also internal, conserved areas of PfEMP1 carry important highly immunogenic epitopes of the molecule.
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5
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Richie TL. Malaria vaccines for travelers. Travel Med Infect Dis 2012; 2:193-210. [PMID: 17291981 DOI: 10.1016/j.tmaid.2004.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Accepted: 07/07/2004] [Indexed: 11/21/2022]
Affiliation(s)
- Thomas L Richie
- Naval Medical Research Center Malaria Program, 503 Robert Grant Avenue, Silver Spring, MD 20910-7500, USA
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Weiss R, Gabler M, Jacobs T, Gilberger TW, Thalhamer J, Scheiblhofer S. Differential effects of C3d on the immunogenicity of gene gun vaccines encoding Plasmodium falciparum and Plasmodium berghei MSP1(42). Vaccine 2010; 28:4515-22. [PMID: 20438877 DOI: 10.1016/j.vaccine.2010.04.054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 03/31/2010] [Accepted: 04/19/2010] [Indexed: 11/18/2022]
Abstract
The complement fragment C3d mediates B-cell activation via simultaneous engagement of the B-cell receptor and CD21 by antigen/C3d conjugates. Several studies demonstrated the potential of C3d as a molecular adjuvant for vaccination. In this work, C3d exerted differential effects on humoral immune responses after gene gun immunization of mice with plasmids encoding the malaria blood stage antigen MSP1(42) depending on the nature of the protein (Plasmodium falciparum vs. Plasmodium berghei MSP), the localization of the C3d moiety (C-terminal vs. N-terminal), and the presence of putative N-glycosylation sites. No improvement of protective efficacy by C3d attachment or mutation of glycosylation sites could be demonstrated by in vitro parasite growth inhibition assays or in vivo blood stage parasite challenges. Our data underscore the controversial role of C3d as molecular adjuvant.
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Affiliation(s)
- Richard Weiss
- Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
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Adhesion of Plasmodium falciparum-infected erythrocytes to human cells: molecular mechanisms and therapeutic implications. Expert Rev Mol Med 2009; 11:e16. [PMID: 19467172 PMCID: PMC2878476 DOI: 10.1017/s1462399409001082] [Citation(s) in RCA: 268] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Severe malaria has a high mortality rate (15–20%) despite treatment with
effective antimalarial drugs. Adjunctive therapies for severe malaria that target the
underlying disease process are therefore urgently required. Adhesion of erythrocytes
infected with Plasmodium falciparum to human cells has a key role in the
pathogenesis of life-threatening malaria and could be targeted with antiadhesion therapy.
Parasite adhesion interactions include binding to endothelial cells (cytoadherence),
rosetting with uninfected erythrocytes and platelet-mediated clumping of infected
erythrocytes. Recent research has started to define the molecular mechanisms of parasite
adhesion, and antiadhesion therapies are being explored. However, many fundamental
questions regarding the role of parasite adhesion in severe malaria remain unanswered.
There is strong evidence that rosetting contributes to severe malaria in sub-Saharan
Africa; however, the identity of other parasite adhesion phenotypes that are implicated in
disease pathogenesis remains unclear. In addition, the possibility of geographic variation
in adhesion phenotypes causing severe malaria, linked to differences in malaria
transmission levels and host immunity, has been neglected. Further research is needed to
realise the untapped potential of antiadhesion adjunctive therapies, which could
revolutionise the treatment of severe malaria and reduce the high mortality rate of the
disease.
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9
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Evidence for globally shared, cross-reacting polymorphic epitopes in the pregnancy-associated malaria vaccine candidate VAR2CSA. Infect Immun 2008; 76:1791-800. [PMID: 18250177 DOI: 10.1128/iai.01470-07] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pregnancy-associated malaria (PAM) is characterized by the placental sequestration of Plasmodium falciparum-infected erythrocytes (IEs) with the ability to bind to chondroitin sulfate A (CSA). VAR2CSA is a leading candidate for a pregnancy malaria vaccine, but its large size ( approximately 350 kDa) and extensive polymorphism may pose a challenge to vaccine development. In this study, rabbits were immunized with individual VAR2CSA Duffy binding-like (DBL) domains expressed in Pichia pastoris or var2csa plasmid DNA and sera were screened on different CSA-binding parasite lines. Rabbit antibodies to three recombinant proteins (DBL1, DBL3, and DBL6) and four plasmid DNAs (DBL1, DBL3, DBL5, and DBL6) reacted with homologous FCR3-CSA IEs. By comparison, antibodies to the DBL4 domain were unable to react with native VAR2CSA protein unless it was first partially proteolyzed with trypsin or chymotrypsin. To investigate the antigenic relationship of geographically diverse CSA-binding isolates, rabbit immune sera were screened on four heterologous CSA-binding lines from different continental origins. Antibodies did not target conserved epitopes exposed in all VAR2CSA alleles; however, antisera to several DBL domains cross-reacted on parasite isolates that had polymorphic loops in common with the homologous immunogen. This study demonstrates that VAR2CSA contains common polymorphic epitopes that are shared between geographically diverse CSA-binding lines.
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10
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Lokugamage KG, Yoshikawa-Iwata N, Ito N, Watts DM, Wyde PR, Wang N, Newman P, Kent Tseng CT, Peters CJ, Makino S. Chimeric coronavirus-like particles carrying severe acute respiratory syndrome coronavirus (SCoV) S protein protect mice against challenge with SCoV. Vaccine 2007; 26:797-808. [PMID: 18191004 PMCID: PMC2267761 DOI: 10.1016/j.vaccine.2007.11.092] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 11/19/2007] [Accepted: 11/29/2007] [Indexed: 01/19/2023]
Abstract
We tested the efficacy of coronavirus-like particles (VLPs) for protecting mice against severe acute respiratory syndrome coronavirus (SCoV) infection. Coexpression of SCoV S protein and E, M and N proteins of mouse hepatitis virus in 293T or CHO cells resulted in the efficient production of chimeric VLPs carrying SCoV S protein. Balb/c mice inoculated with a mixture of chimeric VLPs and alum twice at an interval of four weeks were protected from SCoV challenge, as indicated by the absence of infectious virus in the lungs. The same groups of mice had high levels of SCoV-specific neutralizing antibodies, while mice in the negative control groups, which were not immunized with chimeric VLPs, failed to manifest neutralizing antibodies, suggesting that SCoV-specific neutralizing antibodies are important for the suppression of viral replication within the lungs. Despite some differences in the cellular composition of inflammatory infiltrates, we did not observe any overt lung pathology in the chimeric-VLP-treated mice, when compared to the negative control mice. Our results show that chimeric VLP can be an effective vaccine strategy against SCoV infection.
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Affiliation(s)
- Kumari G Lokugamage
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, United States
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Moll K, Pettersson F, Vogt AM, Jonsson C, Rasti N, Ahuja S, Spångberg M, Mercereau-Puijalon O, Arnot DE, Wahlgren M, Chen Q. Generation of cross-protective antibodies against Plasmodium falciparum sequestration by immunization with an erythrocyte membrane protein 1-duffy binding-like 1 alpha domain. Infect Immun 2006; 75:211-9. [PMID: 17074852 PMCID: PMC1828381 DOI: 10.1128/iai.00749-06] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is an important virulence factor on the surface of infected erythrocytes. Naturally acquired antibodies to PfEMP1 expressed by parasites causing severe malaria are suggested to be protective and of major interest for the development of a vaccine against severe disease. In this study, the PfEMP1 expressed by a parasite clone displaying a multiadhesive phenotype associated with severe malaria was well recognized by sera of malaria semi-immune children. The efficiency of the Duffy binding-like 1 alpha (DBL1 alpha) domain of this PfEMP1 was therefore, alone or in combination with two additional DBL1 alpha domains, evaluated as a potential vaccine candidate using both a rodent model and a primate model. Antibodies against the DBL1 alpha domain were generated by immunization with recombinant DBL1 alpha-Semliki Forest virus particles and recombinant protein and analyzed in vitro. The immunized animals were challenged in vivo with various parasite strains or clones. Immunization with the PfEMP1-DBL1 alpha domain abolished the PfEMP1-dependent sequestration of the homologous strain in immunized rats and substantially inhibited parasite adhesion in immunized monkeys. Protection against sequestration of heterologous parasite strains was also confirmed by direct or indirect challenge in the rat model. These results strongly support the use of the DBL1 alpha domain in the development of a vaccine targeting severe malaria.
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Affiliation(s)
- Kirsten Moll
- Microbiology and Tumorbiology Center, Karolinska Institutet and Swedish Institute for Infectious Disease Control, Nobels väg 16, 171 77 Stockholm, Sweden
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Joergensen L, Turner L, Magistrado P, Dahlbäck MA, Vestergaard LS, Lusingu JP, Lemnge M, Salanti A, Theander TG, Jensen ATR. Limited cross-reactivity among domains of the Plasmodium falciparum clone 3D7 erythrocyte membrane protein 1 family. Infect Immun 2006; 74:6778-84. [PMID: 17015460 PMCID: PMC1698063 DOI: 10.1128/iai.01187-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The var gene-encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family is responsible for antigenic variation and sequestration of infected erythrocytes during malaria. We have previously grouped the 60 PfEMP1 variants of P. falciparum clone 3D7 into groups A and B/A (category A) and groups B, B/C, and C (category non-A). Expression of category A molecules is associated with severe malaria, and that of category non-A molecules is associated with uncomplicated malaria and asymptomatic infection. Here we assessed cross-reactivity among 60 different recombinant PfEMP1 domains derived from clone 3D7 by using a competition enzyme-linked immunosorbent assay and a pool of plasma from 63 malaria-exposed Tanzanian individuals. We conclude that naturally acquired antibodies are largely directed toward epitopes varying between different domains with a few, mainly category A, domains sharing cross-reactive antibody epitopes. Identification of groups of serological cross-reacting molecules is pivotal for the development of vaccines based on PfEMP1.
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Affiliation(s)
- Louise Joergensen
- University of Copenhagen, Department of Medical Microbiology and Immunology, Panum 24.2.24, Blegdamsvej 3, Copenhagen DK-2200, Denmark
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13
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Ndungu FM, Sanni L, Urban B, Stephens R, Newbold CI, Marsh K, Langhorne J. CD4 T cells from malaria-nonexposed individuals respond to the CD36-Binding Domain of Plasmodium falciparum erythrocyte membrane protein-1 via an MHC class II-TCR-independent pathway. THE JOURNAL OF IMMUNOLOGY 2006; 176:5504-12. [PMID: 16622019 DOI: 10.4049/jimmunol.176.9.5504] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have studied the human CD4 T cell response to a functionally conserved domain of Plasmodium falciparum erythrocyte membrane protein-1, cysteine interdomain region-1alpha (CIDR-1alpha). Responses to CIDR-1alpha were striking in that both exposed and nonexposed donors responded. The IFN-gamma response to CIDR-1alpha in the nonexposed donors was partially independent of TCR engagement of MHC class II and peptide. Contrastingly, CD4 T cell and IFN-gamma responses in malaria-exposed donors were MHC class II restricted, suggesting that the CD4 T cell response to CIDR-1alpha in malaria semi-immune adults also has a TCR-mediated component, which may represent a memory response. Dendritic cells isolated from human peripheral blood were activated by CIDR-1alpha to produce IL-12, IL-10, and IL-18. IL-12 was detectable only between 6 and 12 h of culture, whereas the IL-10 continued to increase throughout the 24-h time course. These data strengthen previous observations that P. falciparum interacts directly with human dendritic cells, and suggests that the interaction between CIDR-1alpha and the host cell may be responsible for regulation of the CD4 T cell and cytokine responses to P. falciparum-infected erythrocytes reported previously.
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Affiliation(s)
- Francis M Ndungu
- Division of Parasitology, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
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Ahuja S, Pettersson F, Moll K, Jonsson C, Wahlgren M, Chen Q. Induction of cross-reactive immune responses to NTS-DBL-1alpha/x of PfEMP1 and in vivo protection on challenge with Plasmodium falciparum. Vaccine 2006; 24:6140-54. [PMID: 16837110 DOI: 10.1016/j.vaccine.2006.05.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 04/28/2006] [Accepted: 05/09/2006] [Indexed: 10/24/2022]
Abstract
The interactions of Plasmodium falciparum infected erythrocytes parasitized red blood cells (pRBC) with endothelial receptors and erythrocytes are mediated by multiple Duffy-binding like (DBL) and cysteine-rich interdomain region (CIDR) domains harboured in the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). The success of a subunit vaccine based on PfEMP1 depends on its ability to elicit cross-reactive responses to a substantial number of PfEMP1 variants. We have here evaluated serological PfEMP1 cross-reactivity by immunizing rats with phylogenetically diverse recombinant NTS-DBL-1alpha/x fusion domains from the 3D7 genome parasite emulsified in Montanide ISA 720. Cross-reactivity was elicited to these diverse DBL-1alpha/x domains as measured by ELISA and by immunoblotting. Employing a novel in vivo model of human infected erythrocyte sequestration, immunized animals were challenged with the FCR3S1.2 clone and cross-protection in terms of reduction in lung sequestration amounting to approximately 50% was demonstrated. Our results suggest that immunization with phylogenetically distant DBL-1alpha/x variants, can elicit partial cross-protection to challenge with the parasites harbouring a distant variant. These observations have implications for the design of multi-component vaccines against P. falciparum malaria.
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Affiliation(s)
- Sanjay Ahuja
- Microbiology and Tumor Biology Center (MTC), Karolinska Institute, P.O. Box 280, SE-17177 Stockholm, Sweden
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15
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Weiss R, Scheiblhofer S, Gabler M, Ferreira F, Leitner WW, Thalhamer J. Is Genetic Vaccination against Allergy Possible? Int Arch Allergy Immunol 2006; 139:332-45. [PMID: 16534215 DOI: 10.1159/000091946] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Genetic immunization has proven a powerful method to induce antiallergic immune responses. The underlying functional principle has been described to be based on the recruitment of allergen-specific Th1 cells, CD8+ cells and the establishment of a Th1 cytokine milieu, which prevent the development of a Th2-biased response in a protective setup and can balance an ongoing Th2-type response in a therapeutic situation. Genetic immunization with plasmid DNA offers innovative solutions to the major problems associated with protein immunization, such as crosslinking of pre-existing immunoglobulin E on mast cells/basophils or induction of de novo synthesis of immunoglobulin E by the protein immunization itself. It easily enables the routine production of hypoallergenic vaccines, which do not translate native allergens, thus avoiding potential anaphylactic side effects. DNA vaccines can also be applied as mixtures of single vaccines, making them interesting candidates for treatment based on component-resolved diagnosis, followed by an individualized therapy with the relevant allergens. In addition to the description of up-to-date allergen gene vaccine approaches, this review gives an overview of animal studies dealing with the following topics: danger signals as the inherent adjuvant properties, methods to optimize the vaccine immunogenicity, modulation of the immune response, nonparenteral applications and low-dose vaccination strategies.
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Affiliation(s)
- Richard Weiss
- Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Salzburg, Austria
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Mayer DCG, Mu JB, Kaneko O, Duan J, Su XZ, Miller LH. Polymorphism in the Plasmodium falciparum erythrocyte-binding ligand JESEBL/EBA-181 alters its receptor specificity. Proc Natl Acad Sci U S A 2004; 101:2518-23. [PMID: 14983041 PMCID: PMC356982 DOI: 10.1073/pnas.0307318101] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The malaria parasite lives within erythrocytes and depends on the binding of parasite ligands to host cell surface receptors for invasion. The most virulent human malaria parasite, Plasmodium falciparum, uses multiple ligands, including EBA-175, BAEBL, and JESEBL of the Duffy-binding-like (DBL) family of erythrocyte-binding proteins, for invasion of human erythrocytes. Region II of these parasite ligands is the erythrocyte-binding domain. Previously, we had shown that polymorphism in region II of BAEBL leads to different erythrocyte-binding specificities. We have now identified and characterized the binding specificity of six JESEBL variants. We sequenced region II of JESEBL from 20 P. falciparum clones collected from various parts of the world where malaria is endemic. We observed eight JESEBL variants that contained amino acid polymorphisms at five positions among all clones. Seven of the eight variants could be connected by a single base change that led to an amino acid change. We investigated the functional significance of these polymorphisms by transiently expressing region II from six of JESEBL variants on the surface of Chinese hamster ovary cells. We observed four erythrocyte-binding patterns to enzyme-treated erythrocytes. Thus, P. falciparum DBL ligands JESEBL and BAEBL can recognize multiple receptors on the erythrocyte surface. In contrast to Plasmodium vivax, which has disappeared from West Africa because of the Duffy-negative blood group, P. falciparum may have been successful in endemic areas because it has mutated the ligands of the DBL family to create multiple pathways of invasion, thus making selection of refractory erythrocytes unlikely.
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Affiliation(s)
- D C Ghislaine Mayer
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4 Center Drive, Room 4126, Bethesda, MD 20892-0425, USA
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Gratepanche S, Gamain B, Smith JD, Robinson BA, Saul A, Miller LH. Induction of crossreactive antibodies against the Plasmodium falciparum variant protein. Proc Natl Acad Sci U S A 2003; 100:13007-12. [PMID: 14569009 PMCID: PMC240735 DOI: 10.1073/pnas.2235588100] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The variant antigen Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), present on the surface of P. falciparum-parasitized erythrocytes (PE), plays a central role in naturally acquired immunity, although antibodies to PfEMP1 are predominantly variant specific. To overcome this major limitation for vaccine development, we immunized mice with three cysteine-rich interdomain 1 (CIDR1) domains of PfEMP1 that have the critical function of binding the PE to CD36 on endothelium and thus preventing spleen-dependent killing of the parasite. The immunizations consisted of different combinations of three CIDR1 encoded by DNA followed by recombinant protein boost. Immunizations with a single variant in a prime-boost regimen induced no or low cross-reactivity toward heterologous CIDR1; however, a broad range of crossreactivity was detected in mice that were immunized with all three variants simultaneously. The induced crossreactivity suggests that an anti-PfEMP1 vaccine may be possible.
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Affiliation(s)
- Sylvie Gratepanche
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
| | - Benoit Gamain
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
| | - Joseph D. Smith
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
| | - Bridget A. Robinson
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
| | - Allan Saul
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
| | - Louis H. Miller
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, MD 20852; Seattle Biomedical Research Institute, Seattle, WA 98109; Department of Pathobiology, University of Washington, Seattle, WA 98195; and University of Colorado Health Sciences Center, Denver, CO 80220
- To whom correspondence should be addressed. E-mail:
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