1
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Ji C, Shen H, Su C, Li Y, Chen S, Sharp TH, Xiao J. Plasmodium falciparum has evolved multiple mechanisms to hijack human immunoglobulin M. Nat Commun 2023; 14:2650. [PMID: 37156765 PMCID: PMC10167334 DOI: 10.1038/s41467-023-38320-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 04/25/2023] [Indexed: 05/10/2023] Open
Abstract
Plasmodium falciparum causes the most severe malaria in humans. Immunoglobulin M (IgM) serves as the first line of humoral defense against infection and potently activates the complement pathway to facilitate P. falciparum clearance. A number of P. falciparum proteins bind IgM, leading to immune evasion and severe disease. However, the underlying molecular mechanisms remain unknown. Here, using high-resolution cryo-electron microscopy, we delineate how P. falciparum proteins VAR2CSA, TM284VAR1, DBLMSP, and DBLMSP2 target IgM. Each protein binds IgM in a different manner, and together they present a variety of Duffy-binding-like domain-IgM interaction modes. We further show that these proteins interfere directly with IgM-mediated complement activation in vitro, with VAR2CSA exhibiting the most potent inhibitory effect. These results underscore the importance of IgM for human adaptation of P. falciparum and provide critical insights into its immune evasion mechanism.
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Affiliation(s)
- Chenggong Ji
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
- Changping Laboratory, Beijing, PR China
| | - Hao Shen
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Chen Su
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Yaxin Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Shihua Chen
- Joint Graduate Program of Peking-Tsinghua-NIBS, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Thomas H Sharp
- Department of Cell and Chemical Biology, Section Electron Microscopy, Leiden University Medical Center, 2300, RC, Leiden, The Netherlands
| | - Junyu Xiao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China.
- Changping Laboratory, Beijing, PR China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
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2
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Mitesser V, Dzikowski R. Resetting var Gene Transcription in Plasmodium falciparum. Methods Mol Biol 2022; 2470:211-220. [PMID: 35881348 DOI: 10.1007/978-1-0716-2189-9_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
One of the key mechanisms contributing to the virulence of Plasmodium falciparum is its ability to undergo antigenic switching among antigenically distinct variants of the PfEMP1 adhesive proteins, encoded by the var gene family. To avoid premature exposure of its antigenic repertoire, the parasite transcribes its var genes in a mutually exclusive manner, and switch expression at a very slow rate. This process is epigenetically regulated and it relies on "epigenetic memory," which imprints the single active var gene to remain active for multiple replication cycles. Erasing this epigenetic memory in parasites grown in culture resembles parasites, which egress from the liver. It could therefore be of interest for investigating var switching patterns at the onset of malaria infections. In addition, this procedure could be used for creating heterogeneity of var expression among parasite populations. The methodology described here for resetting of var gene expression is based on promoter titration, also known as molecular sponging.
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Affiliation(s)
- Vera Mitesser
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research Israel-Canada, The Kuvin Center for the Study of Infectious and Tropical Diseases, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ron Dzikowski
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research Israel-Canada, The Kuvin Center for the Study of Infectious and Tropical Diseases, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
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3
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Hviid L, Lopez-Perez M. Analysis by Flow Cytometry of α 2-Macroglobulin and Nonimmune IgM-Binding to Plasmodium falciparum-Infected Erythrocytes. Methods Mol Biol 2022; 2470:435-444. [PMID: 35881364 DOI: 10.1007/978-1-0716-2189-9_32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Several members of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family can bind human serum proteins such as IgM and α2-macroglobulin (α2M). This binding seems to play a role in pathogenesis and immune evasion by improving the avidity of PfEMP1-mediated binding to erythrocyte receptors and/or by masking antibody epitopes in PfEMP1. In this protocol, we describe a flow cytometry-based protocol to evaluate IgM- and α2M-binding to intact and unfixed mature-stage IEs. The method can be used for laboratory clones and field isolates.
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Affiliation(s)
- Lars Hviid
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Centre for Medical Parasitology, Rigshospitalet, Copenhagen, Denmark
| | - Mary Lopez-Perez
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.
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4
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Lopez-Perez M. Single-Cell Sorting of Plasmodium falciparum-Infected Erythrocytes Expressing Particular PfEMP1 Variants. Methods Mol Biol 2022; 2470:79-90. [PMID: 35881340 DOI: 10.1007/978-1-0716-2189-9_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Cultures of Plasmodium falciparum often contain a heterogeneous parasite population. However, several studies require analysis of single infected erythrocytes (IEs) or a clonal parasite population derived from a single parasite. This protocol describes an efficient method for cloning by using fluorescence-activated cell sorting (FACS). For this, an antibody for a particular IEs surface protein it is added to the cell mixture to separate positive and negative IEs for that marker. After the separation, the viable homogeneous population can be used to grow in culture or for molecular analysis.
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Affiliation(s)
- Mary Lopez-Perez
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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5
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Lopez-Perez M, Olsen RW. Immunomagnetic Selection of Plasmodium falciparum-Infected Erythrocytes Expressing Particular PfEMP1 Variants. Methods Mol Biol 2022; 2470:69-78. [PMID: 35881339 DOI: 10.1007/978-1-0716-2189-9_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Plasmodium falciparum expresses a broad range of proteins on the surface of infected erythrocytes (IEs), including members of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family. This protocol describes an immunomagnetic selection method using PfEMP1-specific antibodies to obtain a parasite clone homogenously expressing a particular PfEMP1 protein. The expression of the corresponding PfEMP1 is later tested by flow cytometry, and the selected parasites can be used for further analysis.
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Affiliation(s)
- Mary Lopez-Perez
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Rebecca Wendelboe Olsen
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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6
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Dalgaard N, Barfod L. Production of PfEMP1-Specific Mouse Monoclonal Antibodies. Methods Mol Biol 2022; 2470:391-405. [PMID: 35881361 DOI: 10.1007/978-1-0716-2189-9_29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The PfEMP1 family of proteins expressed on the Plasmodium falciparum-infected erythrocyte (IE) surface is the main target of naturally acquired immunity against malaria. Antibodies capable of opsonizing the IEs and blocking the binding between PfEMP1 and human receptors seems to be one of the main protective mechanisms of the naturally acquired immunity. Therefore this family of antigens is intensively studied. Monoclonal antibodies (mAbs) are a very valuable research tool for studying this diverse family of proteins and their interaction with human receptors. As examples, mAbs can be used to identify protective epitopes, epitopes that are targets of cross-reactive antibodies, and the surface expression of specific PfEMP1 variants. Fusing mouse splenocytes with myeloma cells to generate long-lived antibody secreting hybridoma cell lines have been used since the 1970s for the production of mAbs. In this chapter, we describe a simple, reliable, and relatively fast method for producing PfEMP1-specific mAbs from mouse spleen cells using semisolid HAT selection medium.
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Affiliation(s)
- Nanna Dalgaard
- Centre for Medical Parasitology at Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lea Barfod
- Centre for Medical Parasitology at Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
- Department of Infectious Diseases Copenhagen, University Hospital (Rigshospitalet), Copenhagen, Denmark.
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7
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Tomlinson A, Semblat JP, Gamain B, Chêne A. VAR2CSA-Mediated Host Defense Evasion of Plasmodium falciparum Infected Erythrocytes in Placental Malaria. Front Immunol 2021; 11:624126. [PMID: 33633743 PMCID: PMC7900151 DOI: 10.3389/fimmu.2020.624126] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/23/2020] [Indexed: 12/04/2022] Open
Abstract
Over 30 million women living in P. falciparum endemic areas are at risk of developing malaria during pregnancy every year. Placental malaria is characterized by massive accumulation of infected erythrocytes in the intervillous space of the placenta, accompanied by infiltration of immune cells, particularly monocytes. The consequent local inflammation and the obstruction of the maternofetal exchanges can lead to severe clinical outcomes for both mother and child. Even if protection against the disease can gradually be acquired following successive pregnancies, the malaria parasite has developed a large panel of evasion mechanisms to escape from host defense mechanisms and manipulate the immune system to its advantage. Infected erythrocytes isolated from placentas of women suffering from placental malaria present a unique phenotype and express the pregnancy-specific variant VAR2CSA of the Plasmodium falciparum Erythrocyte Membrane Protein (PfEMP1) family at their surface. The polymorphic VAR2CSA protein is able to mediate the interaction of infected erythrocytes with a variety of host cells including placental syncytiotrophoblasts and leukocytes but also with components of the immune system such as non-specific IgM. This review summarizes the described VAR2CSA-mediated host defense evasion mechanisms employed by the parasite during placental malaria to ensure its survival and persistence.
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Affiliation(s)
- Alice Tomlinson
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERM, Paris, France.,Institut National de la Transfusion Sanguine, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Jean-Philippe Semblat
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERM, Paris, France.,Institut National de la Transfusion Sanguine, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Benoît Gamain
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERM, Paris, France.,Institut National de la Transfusion Sanguine, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Arnaud Chêne
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERM, Paris, France.,Institut National de la Transfusion Sanguine, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
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8
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Abstract
PfEMP1 is the major antigen involved in Plasmodium falciparum-infected erythrocyte sequestration in cerebrovascular endothelium. While some PfEMP1 domains have been associated with clinical phenotypes of malaria, formal associations between the expression of a specific domain and the adhesion properties of clinical isolates are limited. In this context, 73 cerebral malaria (CM) and 98 uncomplicated malaria (UM) Beninese children were recruited. We attempted to correlate the cytoadherence phenotype of Plasmodium falciparum isolates with the clinical presentation and the expression of specific PfEMP1 domains. Cytoadherence level on Hbec-5i and CHO-ICAM-1 cell lines and var genes expression were measured. We also investigated the prevalence of the ICAM-1-binding amino acid motif and dual receptor-binding domains, described as a potential determinant of cerebral malaria pathophysiology. We finally evaluated IgG levels against PfEMP1 recombinant domains (CIDRα1.4, DBLβ3, and CIDRα1.4-DBLβ3). CM isolates displayed higher cytoadherence levels on both cell lines, and we found a correlation between CIDRα1.4-DBLβ1/3 domain expression and CHO-ICAM-1 cytoadherence level. Endothelial protein C receptor (EPCR)-binding domains were overexpressed in CM isolates compared to UM whereas no difference was found in ICAM-1-binding DBLβ1/3 domain expression. Surprisingly, both CM and UM isolates expressed ICAM-1-binding motif and dual receptor-binding domains. There was no difference in IgG response against DBLβ3 between CM and UM isolates expressing ICAM-1-binding DBLβ1/3 domain. It raises questions about the role of this motif in CM pathophysiology, and further studies are needed, especially on the role of DBLβ1/3 without the ICAM-1-binding motif.IMPORTANCE Cerebral malaria pathophysiology remains unknown despite extensive research. PfEMP1 proteins have been identified as the main Plasmodium antigen involved in cerebrovascular endothelium sequestration, but it is unclear which var gene domain is involved in Plasmodium cytoadhesion. EPCR binding is a major determinant of cerebral malaria whereas the ICAM-1-binding role is still questioned. Our study confirmed the EPCR-binding role in CM pathophysiology with a major overexpression of EPCR-binding domains in CM isolates. In contrast, ICAM-1-binding involvement appears less obvious with A-type ICAM-1-binding and dual receptor-binding domain expression in both CM and UM isolates. We did not find any variations in ICAM-1-binding motif sequences in CM compared to UM isolates. UM and CM patients infected with isolates expressing the ICAM-1-binding motif displayed similar IgG levels against DBLβ3 recombinant protein. Our study raises interrogations about the role of these domains in CM physiopathology and questions their use in vaccine strategies against cerebral malaria.
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9
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Lopez-Perez M, van der Puije W, Castberg FC, Ofori MF, Hviid L. Binding of human serum proteins to Plasmodium falciparum-infected erythrocytes and its association with malaria clinical presentation. Malar J 2020; 19:362. [PMID: 33032607 PMCID: PMC7545873 DOI: 10.1186/s12936-020-03438-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/01/2020] [Indexed: 11/10/2022] Open
Abstract
Background The pathogenesis of Plasmodium falciparum malaria is related to the ability of parasite‑infected erythrocytes (IEs) to adhere to the vascular endothelium (cytoadhesion/sequestration) or to surrounding uninfected erythrocytes (rosetting). Both processes are mediated by the expression of members of the clonally variant PfEMP1 parasite protein family on the surface of the IEs. Recent evidence obtained with laboratory-adapted clones indicates that P. falciparum can exploit human serum factors, such as IgM and α2-macroglobulin (α2M), to increase the avidity of PfEMP1-mediated binding to erythrocyte receptors, as well as to evade host PfEMP1-specific immune responses. It has remained unclear whether PfEMP1 variants present in field isolates share these characteristics, and whether they are associated with clinical malaria severity. These issues were investigated here. Methods Children 1–12 years reporting with P. falciparum malaria to Hohoe Municipal Hospital, Ghana were enrolled in the study. Parasites from children with uncomplicated (UM) and severe malaria (SM) were collected. Binding of α2M and IgM from non-immune individuals to erythrocytes infected by P. falciparum isolates from 34 children (UM and SM) were analysed by flow cytometry. Rosetting in the presence of IgM or α2M was also evaluated. Experimental results were analysed according to the clinical presentation of the patients. Results Clinical data from 108 children classified as UM (n = 54) and SM cases (n = 54) were analysed. Prostration, severe malaria anaemia, and hyperparasitaemia were the most frequent complications. Three children were diagnosed with cerebral malaria, and one child died. Parasite isolates from UM (n = 14) and SM (n = 20) children were analysed. Most of the field isolates bound non-immune IgM (33/34), whereas the α2M-binding was less common (23/34). Binding of both non-immune IgM and α2M was higher but not significant in IEs from children with SM than from children with UM. In combination, IgM and α2M supported rosette formation at levels similar to that observed in the presence of 10% human serum. Conclusions The results support the hypothesis that binding of non-immune IgM and/or α2M to IEs facilitates rosette formation and perhaps contributes to P. falciparum malaria severity.
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Affiliation(s)
- Mary Lopez-Perez
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - William van der Puije
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana.,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), College of Basic and Applied Sciences, University of Ghana, Legon, Ghana.,Centre for Medical Parasitology, Department of Infectious Diseases and Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Filip C Castberg
- Centre for Medical Parasitology, Department of Infectious Diseases and Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Michael F Ofori
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Lars Hviid
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Centre for Medical Parasitology, Department of Infectious Diseases and Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
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10
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Oli AN, Obialor WO, Ifeanyichukwu MO, Odimegwu DC, Okoyeh JN, Emechebe GO, Adejumo SA, Ibeanu GC. Immunoinformatics and Vaccine Development: An Overview. Immunotargets Ther 2020; 9:13-30. [PMID: 32161726 PMCID: PMC7049754 DOI: 10.2147/itt.s241064] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 01/25/2020] [Indexed: 12/11/2022] Open
Abstract
The use of vaccines have resulted in a remarkable improvement in global health. It has saved several lives, reduced treatment costs and raised the quality of animal and human lives. Current traditional vaccines came empirically with either vague or completely no knowledge of how they modulate our immune system. Even at the face of potential vaccine design advance, immune-related concerns (as seen with specific vulnerable populations, cases of emerging/re-emerging infectious disease, pathogens with complex lifecycle and antigenic variability, need for personalized vaccinations, and concerns for vaccines' immunological safety -specifically vaccine likelihood to trigger non-antigen-specific responses that may cause autoimmunity and vaccine allergy) are being raised. And these concerns have driven immunologists toward research for a better approach to vaccine design that will consider these challenges. Currently, immunoinformatics has paved the way for a better understanding of some infectious disease pathogenesis, diagnosis, immune system response and computational vaccinology. The importance of this immunoinformatics in the study of infectious diseases is diverse in terms of computational approaches used, but is united by common qualities related to host–pathogen relationship. Bioinformatics methods are also used to assign functions to uncharacterized genes which can be targeted as a candidate in vaccine design and can be a better approach toward the inclusion of women that are pregnant into vaccine trials and programs. The essence of this review is to give insight into the need to focus on novel computational, experimental and computation-driven experimental approaches for studying of host–pathogen interactions and thus making a case for its use in vaccine development.
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Affiliation(s)
- Angus Nnamdi Oli
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka, Nigeria
| | - Wilson Okechukwu Obialor
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka, Nigeria
| | - Martins Ositadimma Ifeanyichukwu
- Department of Immunology, College of Health Sciences, Faculty of Medicine, Nnamdi Azikiwe University, Anambra, Nigeria.,Department of Medical Laboratory Science,Faculty of Health Science and Technology, College of Health Sciences, Nnamdi Azikiwe University,Nnewi Campus, Nnewi, Nigeria
| | - Damian Chukwu Odimegwu
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, University of Nigeria Nsukka, Enugu, Nigeria
| | - Jude Nnaemeka Okoyeh
- Department of Biology and Clinical Laboratory Science, Division of Arts and Sciences, Neumann University, Aston, PA 19014-1298, USA
| | - George Ogonna Emechebe
- Department of Pediatrics, Faculty of Clinical Medicine, Chukwuemeka Odumegwu Ojukwu University, Awka, Nigeria
| | - Samson Adedeji Adejumo
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka, Nigeria
| | - Gordon C Ibeanu
- Department of Pharmaceutical Science, North Carolina Central University, Durham, NC 27707, USA
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11
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Jensen AR, Adams Y, Hviid L. Cerebral Plasmodium falciparum malaria: The role of PfEMP1 in its pathogenesis and immunity, and PfEMP1-based vaccines to prevent it. Immunol Rev 2020; 293:230-252. [PMID: 31562653 PMCID: PMC6972667 DOI: 10.1111/imr.12807] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 09/04/2019] [Accepted: 09/09/2019] [Indexed: 12/13/2022]
Abstract
Malaria, a mosquito-borne infectious disease caused by parasites of the genus Plasmodium continues to be a major health problem worldwide. The unicellular Plasmodium-parasites have the unique capacity to infect and replicate within host erythrocytes. By expressing variant surface antigens Plasmodium falciparum has evolved to avoid protective immune responses; as a result in endemic areas anti-malaria immunity develops gradually over many years of multiple and repeated infections. We are studying the role of Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) expressed by asexual stages of P. falciparum responsible for the pathogenicity of severe malaria. The immunopathology of falciparum malaria has been linked to cyto-adhesion of infected erythrocytes to specific host receptors. A greater appreciation of the PfEMP1 molecules important for the development of protective immunity and immunopathology is a prerequisite for the rational discovery and development of a safe and protective anti-disease malaria vaccine. Here we review the role of ICAM-1 and EPCR receptor adhering falciparum-parasites in the development of severe malaria; we discuss our current research to understand the factors involved in the pathogenesis of cerebral malaria and the feasibility of developing a vaccine targeted specifically to prevent this disease.
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Affiliation(s)
- Anja Ramstedt Jensen
- Centre for Medical Parasitology at Department of Immunology and MicrobiologyFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Yvonne Adams
- Centre for Medical Parasitology at Department of Immunology and MicrobiologyFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Lars Hviid
- Centre for Medical Parasitology at Department of Immunology and MicrobiologyFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Department of Infectious DiseasesRigshospitaletCopenhagenDenmark
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12
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Storm J, Jespersen JS, Seydel KB, Szestak T, Mbewe M, Chisala NV, Phula P, Wang CW, Taylor TE, Moxon CA, Lavstsen T, Craig AG. Cerebral malaria is associated with differential cytoadherence to brain endothelial cells. EMBO Mol Med 2019; 11:emmm.201809164. [PMID: 30610112 PMCID: PMC6365927 DOI: 10.15252/emmm.201809164] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Sequestration of Plasmodium falciparum‐infected erythrocytes (IE) within the brain microvasculature is a hallmark of cerebral malaria (CM). Using a microchannel flow adhesion assay with TNF‐activated primary human microvascular endothelial cells, we demonstrate that IE isolated from Malawian paediatric CM cases showed increased binding to brain microvascular endothelial cells compared to IE from uncomplicated malaria (UM) cases. Further, UM isolates showed significantly greater adhesion to dermal than to brain microvascular endothelial cells. The major mediator of parasite adhesion is P. falciparum erythrocyte membrane protein 1, encoded by var genes. Higher levels of var gene transcripts predicted to bind host endothelial protein C receptor (EPCR) and ICAM‐1 were detected in CM isolates. These data provide further evidence for differential tissue binding in severe and uncomplicated malaria syndromes, and give additional support to the hypothesis that CM pathology is based on increased cytoadherence of IE in the brain microvasculature.
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Affiliation(s)
- Janet Storm
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK .,Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,College of Medicine, University of Malawi, Blantyre, Malawi
| | - Jakob S Jespersen
- Department of International Health, Immunology & Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Karl B Seydel
- College of Medicine, University of Malawi, Blantyre, Malawi.,Blantyre Malaria Project, College of Medicine, University of Malawi, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - Tadge Szestak
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Maurice Mbewe
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Ngawina V Chisala
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Patricia Phula
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Christian W Wang
- Department of International Health, Immunology & Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Terrie E Taylor
- Blantyre Malaria Project, College of Medicine, University of Malawi, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - Christopher A Moxon
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.,Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Thomas Lavstsen
- Department of International Health, Immunology & Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Alister G Craig
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
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13
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Quintana MDP, Ecklu-Mensah G, Tcherniuk SO, Ditlev SB, Oleinikov AV, Hviid L, Lopez-Perez M. Comprehensive analysis of Fc-mediated IgM binding to the Plasmodium falciparum erythrocyte membrane protein 1 family in three parasite clones. Sci Rep 2019; 9:6050. [PMID: 30988351 PMCID: PMC6465264 DOI: 10.1038/s41598-019-42585-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 04/03/2019] [Indexed: 12/14/2022] Open
Abstract
PfEMP1 is a family of adhesive proteins expressed on the surface of Plasmodium falciparum-infected erythrocytes (IEs), where they mediate adhesion of IEs to a range of host receptors. Efficient PfEMP1-dependent IE sequestration often depends on soluble serum proteins, including IgM. Here, we report a comprehensive investigation of which of the about 60 var gene-encoded PfEMP1 variants per parasite genome can bind IgM via the Fc part of the antibody molecule, and which of the constituent domains of those PfEMP1 are involved. We erased the epigenetic memory of var gene expression in three distinct P. falciparum clones, 3D7, HB3, and IT4/FCR3 by promoter titration, and then isolated individual IEs binding IgM from malaria-unexposed individuals by fluorescence-activated single-cell sorting. The var gene transcription profiles of sub-clones measured by real-time qPCR were used to identify potential IgM-binding PfEMP1 variants. Recombinant DBL and CIDR domains corresponding to those variants were tested by ELISA and protein arrays to confirm their IgM-binding capacity. Selected DBL domains were used to raise specific rat anti-sera to select IEs with uniform expression of candidate PfEMP1 proteins. Our data document that IgM-binding PfEMP1 proteins are common in each of the three clones studied, and that the binding epitopes are mainly found in DBLε and DBLζ domains near the C-terminus.
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Affiliation(s)
- Maria Del Pilar Quintana
- Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gertrude Ecklu-Mensah
- Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Sergey O Tcherniuk
- Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Sisse Bolm Ditlev
- Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Andrew V Oleinikov
- Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Lars Hviid
- Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark.
| | - Mary Lopez-Perez
- Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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14
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Kessler A, Dankwa S, Bernabeu M, Harawa V, Danziger SA, Duffy F, Kampondeni SD, Potchen MJ, Dambrauskas N, Vigdorovich V, Oliver BG, Hochman SE, Mowrey WB, MacCormick IJC, Mandala WL, Rogerson SJ, Sather DN, Aitchison JD, Taylor TE, Seydel KB, Smith JD, Kim K. Linking EPCR-Binding PfEMP1 to Brain Swelling in Pediatric Cerebral Malaria. Cell Host Microbe 2017; 22:601-614.e5. [PMID: 29107642 DOI: 10.1016/j.chom.2017.09.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/06/2017] [Accepted: 09/22/2017] [Indexed: 11/16/2022]
Abstract
Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.
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Affiliation(s)
- Anne Kessler
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Selasi Dankwa
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Maria Bernabeu
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Visopo Harawa
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi
| | | | - Fergal Duffy
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Michael J Potchen
- Department of Imaging Sciences, University of Rochester, Rochester, NY 14642, USA
| | | | | | - Brian G Oliver
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Sarah E Hochman
- Department of Medicine, New York University Langone Health, New York, NY 10016, USA
| | - Wenzhu B Mowrey
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Ian J C MacCormick
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; Department of Eye and Vision Sciences, University of Liverpool, Liverpool L69 3BX, UK
| | - Wilson L Mandala
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi; Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo BT3, Malawi
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute, The University of Melbourne, Melbourne, VIC 3000, Australia
| | - D Noah Sather
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Terrie E Taylor
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Karl B Seydel
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA.
| | - Joseph D Smith
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - Kami Kim
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA.
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15
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Wahlgren M, Goel S, Akhouri RR. Variant surface antigens of Plasmodium falciparum and their roles in severe malaria. Nat Rev Microbiol 2017; 15:479-491. [DOI: 10.1038/nrmicro.2017.47] [Citation(s) in RCA: 142] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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16
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Bernabeu M, Smith JD. EPCR and Malaria Severity: The Center of a Perfect Storm. Trends Parasitol 2016; 33:295-308. [PMID: 27939609 DOI: 10.1016/j.pt.2016.11.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/07/2016] [Accepted: 11/10/2016] [Indexed: 12/20/2022]
Abstract
Severe malaria due to Plasmodium falciparum infection causes nearly half a million deaths per year. The different symptomatology and disease manifestations among patients have hampered understanding of severe malaria pathology and complicated efforts to develop targeted disease interventions. Infected erythrocyte sequestration in the microvasculature plays a critical role in the development of severe disease, and there is increasing evidence that cytoadherent parasites interact with host factors to enhance the damage caused by the parasite. The recent discovery that parasite binding to endothelial protein C receptor (EPCR) is associated with severe disease has suggested new mechanisms of pathology and provided new avenues for severe malaria adjunctive therapy research.
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Affiliation(s)
- Maria Bernabeu
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Joseph D Smith
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
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17
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Severe adult malaria is associated with specific PfEMP1 adhesion types and high parasite biomass. Proc Natl Acad Sci U S A 2016; 113:E3270-9. [PMID: 27185931 DOI: 10.1073/pnas.1524294113] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The interplay between cellular and molecular determinants that lead to severe malaria in adults is unexplored. Here, we analyzed parasite virulence factors in an infected adult population in India and investigated whether severe malaria isolates impair endothelial protein C receptor (EPCR), a protein involved in coagulation and endothelial barrier permeability. Severe malaria isolates overexpressed specific members of the Plasmodium falciparum var gene/PfEMP1 (P. falciparum erythrocyte membrane protein 1) family that bind EPCR, including DC8 var genes that have previously been linked to severe pediatric malaria. Machine learning analysis revealed that DC6- and DC8-encoding var transcripts in combination with high parasite biomass were the strongest indicators of patient hospitalization and disease severity. We found that DC8 CIDRα1 domains from severe malaria isolates had substantial differences in EPCR binding affinity and blockade activity for its ligand activated protein C. Additionally, even a low level of inhibition exhibited by domains from two cerebral malaria isolates was sufficient to interfere with activated protein C-barrier protective activities in human brain endothelial cells. Our findings demonstrate an interplay between parasite biomass and specific PfEMP1 adhesion types in the development of adult severe malaria, and indicate that low impairment of EPCR function may contribute to parasite virulence.
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18
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Crosnier C, Iqbal Z, Knuepfer E, Maciuca S, Perrin AJ, Kamuyu G, Goulding D, Bustamante LY, Miles A, Moore SC, Dougan G, Holder AA, Kwiatkowski DP, Rayner JC, Pleass RJ, Wright GJ. Binding of Plasmodium falciparum Merozoite Surface Proteins DBLMSP and DBLMSP2 to Human Immunoglobulin M Is Conserved among Broadly Diverged Sequence Variants. J Biol Chem 2016; 291:14285-14299. [PMID: 27226583 PMCID: PMC4933183 DOI: 10.1074/jbc.m116.722074] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 11/17/2022] Open
Abstract
Diversity at pathogen genetic loci can be driven by host adaptive immune selection pressure and may reveal proteins important for parasite biology. Population-based genome sequencing of Plasmodium falciparum, the parasite responsible for the most severe form of malaria, has highlighted two related polymorphic genes called dblmsp and dblmsp2, which encode Duffy binding-like (DBL) domain-containing proteins located on the merozoite surface but whose function remains unknown. Using recombinant proteins and transgenic parasites, we show that DBLMSP and DBLMSP2 directly and avidly bind human IgM via their DBL domains. We used whole genome sequence data from over 400 African and Asian P. falciparum isolates to show that dblmsp and dblmsp2 exhibit extreme protein polymorphism in their DBL domain, with multiple variants of two major allelic classes present in every population tested. Despite this variability, the IgM binding function was retained across diverse sequence representatives. Although this interaction did not seem to have an effect on the ability of the parasite to invade red blood cells, binding of DBLMSP and DBLMSP2 to IgM inhibited the overall immunoreactivity of these proteins to IgG from patients who had been exposed to the parasite. This suggests that IgM binding might mask these proteins from the host humoral immune system.
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Affiliation(s)
- Cécile Crosnier
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Zamin Iqbal
- Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Ellen Knuepfer
- Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Sorina Maciuca
- Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Abigail J Perrin
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Gathoni Kamuyu
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - David Goulding
- Microbial Pathogenesis Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Leyla Y Bustamante
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Alistair Miles
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Shona C Moore
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; Warwick Systems Biology Centre, Senate House, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gordon Dougan
- Microbial Pathogenesis Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Anthony A Holder
- Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Dominic P Kwiatkowski
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Richard J Pleass
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Gavin J Wright
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom.
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19
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Soni R, Sharma D, Bhatt TK. Plasmodium falciparum Secretome in Erythrocyte and Beyond. Front Microbiol 2016; 7:194. [PMID: 26925057 PMCID: PMC4759260 DOI: 10.3389/fmicb.2016.00194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/05/2016] [Indexed: 01/19/2023] Open
Abstract
Plasmodium falciparum is the causative agent of deadly malaria disease. It is an intracellular eukaryote and completes its multi-stage life cycle spanning the two hosts viz, mosquito and human. In order to habituate within host environment, parasite conform several strategies to evade host immune responses such as surface antigen polymorphism or modulation of host immune system and it is mediated by secretion of proteins from parasite to the host erythrocyte and beyond, collectively known as, malaria secretome. In this review, we will discuss about the deployment of parasitic secretory protein in mechanism implicated for immune evasion, protein trafficking, providing virulence, changing permeability and cyto-adherence of infected erythrocyte. We will be covering the possibilities of developing malaria secretome as a drug/vaccine target. This gathered information will be worthwhile in depicting a well-organized picture for host-pathogen interplay during the malaria infection and may also provide some clues for the development of novel anti-malarial therapies.
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Affiliation(s)
- Rani Soni
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan Rajasthan, India
| | - Drista Sharma
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan Rajasthan, India
| | - Tarun K Bhatt
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan Rajasthan, India
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20
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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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21
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Pleass RJ, Moore SC, Stevenson L, Hviid L. Immunoglobulin M: Restrainer of Inflammation and Mediator of Immune Evasion by Plasmodium falciparum Malaria. Trends Parasitol 2015; 32:108-119. [PMID: 26597020 DOI: 10.1016/j.pt.2015.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/16/2015] [Accepted: 09/23/2015] [Indexed: 02/06/2023]
Abstract
Immunoglobulin M (IgM) is an ancient antibody class that is found in all vertebrates, with the exception of coelacanths, and is indispensable in both innate and adaptive immunity. The equally ancient human malaria parasite, Plasmodium falciparum, formed an intimate relationship with IgM with which it co-evolved. In this article, we discuss the association between IgM and human malaria parasites, building on several recent publications that implicate IgM as a crucial molecule that determines both host and parasite survival. Consequently, a better understanding of this association may lead to the development of improved intervention strategies.
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Affiliation(s)
- Richard J Pleass
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Shona C Moore
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK; Warwick Systems Biology Centre, Senate House, University of Warwick, Coventry, CV4 7AL, UK
| | - Liz Stevenson
- Centre for Medical Parasitology, Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Lars Hviid
- Centre for Medical Parasitology, Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark.
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