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Moussiliou A, Turner L, Cottrell G, Doritchamou J, Gbédandé K, Fievet N, Luty AJF, Massougbodji A, Theander TG, Deloron P, Lavstsen T, Tuikue Ndam N. Dynamics of PfEMP1 Antibody Profile From Birth to 12 Months of Age in Beninese Infants. J Infect Dis 2021; 221:2010-2017. [PMID: 32002541 DOI: 10.1093/infdis/jiaa043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/24/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Plasmodium falciparum-infected erythrocytes bind to specific endothelial cell receptors via members of the PfEMP1 family exported onto the erythrocyte surface. These interactions are mediated by different types of cysteine-rich interdomain region (CIDR) domains found in the N-terminal region of all PfEMP1. CIDRα1 domains bind endothelial protein C receptor (EPCR), CIDRα2-6 domains bind CD36, whereas the receptor specificity of CIDRβ/γ/δ domains is unknown. METHODS In this study, we investigated the level of immunoglobulin (Ig)G targeting the different types of PfEMP1 CIDR during the first year of life. We used plasma collected longitudinally from children of pregnant women who had been followed closely through pregnancy. RESULTS Antibodies to CIDRα1 domains were more frequent in cord blood compared with antibodies to CIDRα2-6 domains. Higher IgG levels to EPCR-binding CIDRα1 variants positively correlated with the timing of first infections. Antibodies to all PfEMP1 types declined at similar rates to the point of disappearance over the first 6 months of life. At 12 months, children had acquired antibody to all types of CIDR domains, mostly in children with documented P falciparum infections. CONCLUSIONS These observations agree with the notion that the timing and phenotype of first P falciparum infections in life are influenced by the immune status of the mother.
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Affiliation(s)
| | - L Turner
- 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
| | - G Cottrell
- Université de Paris, MERIT, IRD, Paris, France
| | - J Doritchamou
- Institut de Recherche Clinique du Bénin, Université d'Abomey-Calavi, Cotonou, Bénin
| | - K Gbédandé
- Institut de Recherche Clinique du Bénin, Université d'Abomey-Calavi, Cotonou, Bénin
| | - N Fievet
- Université de Paris, MERIT, IRD, Paris, France
| | - A J F Luty
- Université de Paris, MERIT, IRD, Paris, France
| | - A Massougbodji
- Institut de Recherche Clinique du Bénin, Université d'Abomey-Calavi, Cotonou, Bénin
| | - T G Theander
- 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
| | - P Deloron
- Université de Paris, MERIT, IRD, Paris, France
| | - T Lavstsen
- 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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2
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Joste V, Maurice L, Bertin GI, Aubouy A, Boumédiène F, Houzé S, Ajzenberg D, Argy N, Massougbodji A, Dossou-Dagba I, Alao MJ, Cot M, Deloron P, Faucher JF. Identification of Plasmodium falciparum and host factors associated with cerebral malaria: description of the protocol for a prospective, case-control study in Benin (NeuroCM). BMJ Open 2019; 9:e027378. [PMID: 31142528 PMCID: PMC6549734 DOI: 10.1136/bmjopen-2018-027378] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
INTRODUCTION In 2016, an estimated 216 million cases and 445 000 deaths of malaria occurred worldwide, in 91 countries. In Benin, malaria causes 26.8% of consultation and hospitalisation motif in the general population and 20.9% in children under 5 years old.The goal of the NeuroCM project is to identify the causative factors of neuroinflammation in the context of cerebral malaria. There are currently very few systematic data from West Africa on the aetiologies and management of non-malarial non-traumatic coma in small children, and NeuroCM will help to fill this gap. We postulate that an accurate understanding of molecular and cellular mechanisms involved in neuroinflammation may help to define efficient strategies to prevent and manage cerebral malaria. METHODS AND ANALYSIS This is a prospective, case-control study comparing cerebral malaria to uncomplicated malaria and non-malarial non-traumatic coma. This study takes place in Benin, precisely in Cotonou for children with coma and in Sô-Ava district for children with uncomplicated malaria. We aim to include 300 children aged between 24 and 71 months and divided in three different clinical groups during 12 months (from December 2017 to November 2018) with a 21 to 28 days follow-up for coma. Study data, including clinical, biological and research results will be collected and managed using CSOnline-Ennov Clinical. ETHICS AND DISSEMINATION Ethics approval for the NeuroCM study has been obtained from Comité National d'Ethique pour la Recherche en santé of Benin (n°67/MS/DC/SGM/DRFMT/CNERS/SA; 10/17/2017). NeuroCM study has also been approved by Comité consultatif de déontologie et d'éthique of Institut de Recherche pour le Développement (IRD; 10/24/2017). The study results will be disseminated through the direct consultations with the WHO's Multilateral Initiative on Malaria (TDR-MIM) and Roll Back Malaria programme, through scientific meetings and peer-reviewed publications in scientific or medical journals, and through guidelines and booklets.
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Affiliation(s)
| | - Laurine Maurice
- MERIT, Sorbonne Paris Cité, IRD, 75006, Paris, France
- PHARMADEV, Université de Toulouse, IRD, UPS, France, Toulouse, France
| | | | - Agnès Aubouy
- PHARMADEV, Université de Toulouse, IRD, UPS, France, Toulouse, France
| | | | - Sandrine Houzé
- MERIT, Sorbonne Paris Cité, IRD, 75006, Paris, France
- Parasitology Laboratory, Hopital Bichat - Claude-Bernard, Paris, France
| | | | - Nicolas Argy
- MERIT, Sorbonne Paris Cité, IRD, 75006, Paris, France
- Parasitology Laboratory, Hopital Bichat - Claude-Bernard, Paris, France
| | | | | | - Maroufou Jules Alao
- Paediatric Department, Mother and Child University and Hospital Center (CHU-MEL), Cotonou, Benin
| | - Michel Cot
- MERIT, Sorbonne Paris Cité, IRD, 75006, Paris, France
| | | | - Jean-François Faucher
- Tropical Neuroepidemiology, INSERM UMR 1094, Limoges, France
- Infectious diseases and tropical medicine department, Limoges University Hospital, Limoges, France
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3
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Manirakiza A, Serdouma E, Ngbalé RN, Moussa S, Gondjé S, Degana RM, Bata GGB, Moyen JM, Delmont J, Grésenguet G, Sepou A. A brief review on features of falciparum malaria during pregnancy. J Public Health Afr 2017; 8:668. [PMID: 29456824 PMCID: PMC5812306 DOI: 10.4081/jphia.2017.668] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 11/22/2022] Open
Abstract
Malaria in pregnancy is a serious public health problem in tropical areas. Frequently, the placenta is infected by accumulation of Plasmodium falciparum-infected erythrocytes in the intervillous space. Falciparum malaria acts during pregnancy by a range of mechanisms, and chronic or repeated infection and co-infections have insidious effects. The susceptibility of pregnant women to malaria is due to both immunological and humoral changes. Until a malaria vaccine becomes available, the deleterious effects of malaria in pregnancy can be avoided by protection against infection and prompt treatment with safe, effective antimalarial agents; however, concurrent infections such as with HIV and helminths during pregnancy are jeopardizing malaria control in sub-Saharan Africa.
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Affiliation(s)
| | | | | | - Sandrine Moussa
- Pasteur Institute of Bangui, Bangui, Central African Republic
| | - Samuel Gondjé
- Ministry of Public Health, Population and AIDS Control, Bangui, Central African Republic
| | - Rock Mbetid Degana
- Ministry of Public Health, Population and AIDS Control, Bangui, Central African Republic
| | | | - Jean Methode Moyen
- Ministry of Public Health, Population and AIDS Control, Bangui, Central African Republic
| | - Jean Delmont
- Center for Training and Research in Tropical Medicine and Health, Faculty of Medicine North, Marseille, France
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4
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Patel JC, Hathaway NJ, Parobek CM, Thwai KL, Madanitsa M, Khairallah C, Kalilani-Phiri L, Mwapasa V, Massougbodji A, Fievet N, Bailey JA, Ter Kuile FO, Deloron P, Engel SM, Taylor SM, Juliano JJ, Tuikue Ndam N, Meshnick SR. Increased risk of low birth weight in women with placental malaria associated with P. falciparum VAR2CSA clade. Sci Rep 2017; 7:7768. [PMID: 28801627 PMCID: PMC5554196 DOI: 10.1038/s41598-017-04737-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 05/30/2017] [Indexed: 11/17/2022] Open
Abstract
Pregnancy associated malaria (PAM) causes adverse pregnancy and birth outcomes owing to Plasmodium falciparum accumulation in the placenta. Placental accumulation is mediated by P. falciparum protein VAR2CSA, a leading PAM-specific vaccine target. The extent of its antigen diversity and impact on clinical outcomes remain poorly understood. Through amplicon deep-sequencing placental malaria samples from women in Malawi and Benin, we assessed sequence diversity of VAR2CSA’s ID1-DBL2x region, containing putative vaccine targets and estimated associations of specific clades with adverse birth outcomes. Overall, var2csa diversity was high and haplotypes subdivided into five clades, the largest two defined by homology to parasites strains, 3D7 or FCR3. Across both cohorts, compared to women infected with only FCR3-like variants, women infected with only 3D7-like variants delivered infants with lower birthweight (difference: −267.99 g; 95% Confidence Interval [CI]: −466.43 g,−69.55 g) and higher odds of low birthweight (<2500 g) (Odds Ratio [OR] 5.41; 95% CI:0.99,29.52) and small-for-gestational-age (OR: 3.65; 95% CI: 1.01,13.38). In two distinct malaria-endemic African settings, parasites harboring 3D7-like variants of VAR2CSA were associated with worse birth outcomes, supporting differential effects of infection with specific parasite strains. The immense diversity coupled with differential clinical effects of this diversity suggest that an effective VAR2CSA-based vaccine may require multivalent activity.
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Affiliation(s)
- Jaymin C Patel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA.
| | - Nicholas J Hathaway
- Program in Bioinformatics and Integrative Biology, University of Massachusetts, Worcester, MA, USA
| | - Christian M Parobek
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, USA
| | - Kyaw L Thwai
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA
| | - Mwayiwawo Madanitsa
- College of Medicine, University of Malawi, Blantyre, Malawi.,Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Carole Khairallah
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Victor Mwapasa
- College of Medicine, University of Malawi, Blantyre, Malawi
| | - Achille Massougbodji
- Centre d'Etude et de Recherche sur le paludisme associé à la Grossesse et à l'Enfance, Université d'Abomey-Calavi, Cotonou, Benin
| | - Nadine Fievet
- COMUE Sorbonne Paris Cité, Université Paris Descartes, Paris, France.,UMR216 - MERIT, Institut de Recherche pour le Développement, Paris, France
| | - Jeffery A Bailey
- Program in Bioinformatics and Integrative Biology, University of Massachusetts, Worcester, MA, USA.,Division of Transfusion Medicine, Department of Medicine, University of Massachusetts, Worcester, MA, USA
| | - Feiko O Ter Kuile
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Philippe Deloron
- COMUE Sorbonne Paris Cité, Université Paris Descartes, Paris, France.,UMR216 - MERIT, Institut de Recherche pour le Développement, Paris, France
| | - Stephanie M Engel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA
| | - Steve M Taylor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA.,Division of Infectious Diseases, Duke University Medical Center and Duke Global Health Institute, Durham, NC, USA
| | - Jonathan J Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA.,Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, USA.,Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Nicaise Tuikue Ndam
- COMUE Sorbonne Paris Cité, Université Paris Descartes, Paris, France.,UMR216 - MERIT, Institut de Recherche pour le Développement, Paris, France
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA
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Identification of VAR2CSA domain-specific inhibitory antibodies of the Plasmodium falciparum erythrocyte membrane protein 1 using a novel flow cytometry assay. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:433-42. [PMID: 23345587 DOI: 10.1128/cvi.00638-12] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
VAR2CSA, a member of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family, is a leading candidate for use in vaccines to protect first-time mothers from placental malaria (PM). VAR2CSA, which is comprised of a series of six Duffy binding-like (DBL) domains, binds chondroitin sulfate A (CSA) on placental syncytiotrophoblast. Several recombinant DBL domains have been shown to bind CSA. In order to identify and develop recombinant proteins suitable for clinical development, DBL2X and DBL3X, as well as their respective third subdomain (S3) from the FCR3 parasite clone, were expressed in Escherichia coli, refolded, and purified. All but DBL3X-S3 recombinant proteins bound to CSA expressed on Chinese hamster ovary (CHO)-K1 cells but not to CHO-pgsA745 cells, which are CSA negative as determined by flow cytometry. All but DBL3X-S3 bound to CSA on chondroitin sulfate proteoglycan (CSPG) as determined by surface plasmon resonance (SPR) analysis. Purified IgG from rats and rabbits immunized with these four recombinant proteins bound homologous and some heterologous parasite-infected erythrocytes (IE). Using a novel flow cytometry inhibition-of-binding assay (flow-IBA), antibodies against DBL3X-S3 inhibited 35% and 45% of IE binding to CSA on CHO-K1 cells compared to results for soluble CSA (sCSA) and purified multigravida (MG) IgG, respectively, from areas in Tanzania to which malaria is endemic. Antibodies generated against the other domains provided little or no inhibition of IE binding to CSA on CHO-K1 cells as determined by the flow cytometry inhibition-of-binding assay. These results demonstrate for the first time the ability to identify antibodies to VAR2CSA DBL domains and subdomains capable of inhibiting VAR2CSA parasite-IE binding to CSA by flow cytometry. The flow cytometry inhibition-of-binding assay was robust and provided an accurate, reproducible, and reliable means to identify blocking of IE binding to CSA and promises to be significant in the development of a vaccine to protect pregnant women.
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6
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Buckee CO, Recker M. Evolution of the multi-domain structures of virulence genes in the human malaria parasite, Plasmodium falciparum. PLoS Comput Biol 2012; 8:e1002451. [PMID: 22511852 PMCID: PMC3325180 DOI: 10.1371/journal.pcbi.1002451] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 02/10/2012] [Indexed: 11/30/2022] Open
Abstract
The var gene family of Plasmodium falciparum encodes the immunodominant variant surface antigens PfEMP1. These highly polymorphic proteins are important virulence factors that mediate cytoadhesion to a variety of host tissues, causing sequestration of parasitized red blood cells in vital organs, including the brain or placenta. Acquisition of variant-specific antibodies correlates with protection against severe malarial infections; however, understanding the relationship between gene expression and infection outcome is complicated by the modular genetic architectures of var genes that encode varying numbers of antigenic domains with differential binding specificities. By analyzing the domain architectures of fully sequenced var gene repertoires we reveal a significant, non-random association between the number of domains comprising a var gene and their sequence conservation. As such, var genes can be grouped into those that are short and diverse and genes that are long and conserved, suggesting gene length as an important characteristic in the classification of var genes. We then use an evolutionary framework to demonstrate how the same evolutionary forces acting on the level of an individual gene may have also shaped the parasite's gene repertoire. The observed associations between sequence conservation, gene architecture and repertoire structure can thus be explained by a trade-off between optimizing within-host fitness and minimizing between-host immune selection pressure. Our results demonstrate how simple evolutionary mechanisms can explain var gene structuring on multiple levels and have important implications for understanding the multifaceted epidemiology of P. falciparum malaria. Plasmodium falciparum, the most severe of the human malarias, contains within its genome a family of ∼60 var genes which play an important role in disease pathology and maintenance of chronic infections. Var genes have a modular genetic architecture and encode varying numbers of binding domains with specific preferences to a range of host tissues. Given the availability of host receptors for binding and the immunogenic properties of each domain it is not clear why genes encode multiple domains at once and how these are structured within each parasite's antigenic repertoire. Here we investigate the domain architecture of these important virulence genes and highlight an evolutionary trade-off between maintaining within-host fitness and optimizing between-host transmission success as an important driver in structuring var genes and var gene repertoires alike.
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Affiliation(s)
- Caroline O. Buckee
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Mario Recker
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- * E-mail:
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7
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Bordbar B, Tuikue-Ndam N, Bigey P, Doritchamou J, Scherman D, Deloron P. Identification of Id1-DBL2X of VAR2CSA as a key domain inducing highly inhibitory and cross-reactive antibodies. Vaccine 2012; 30:1343-8. [PMID: 22226864 DOI: 10.1016/j.vaccine.2011.12.065] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 12/09/2011] [Accepted: 12/13/2011] [Indexed: 11/29/2022]
Abstract
PURPOSE OF THE RESEARCH VAR2CSA is considered as the main target of protective immunity against pregnancy-associated malaria. VAR2CSA high molecular weight complicates scaling up production of VAR2CSA recombinant protein for large-scale vaccination programmes. We previously demonstrated that antibodies induced by NTS-DBL1X-Id1-DBL2X efficiently block parasite binding to CSA in a similar manner to antibodies induced by the full-length extracellular part of VAR2CSA. In order to identifying the shortest fragment of VAR2CSA carrying major protective epitopes able to elicit inhibitory antibodies, we performed a refined antigenic mapping of NTS-DBL1X-Id1-DBL2X through a DNA vaccination technique. PRINCIPAL RESULTS Five single or double domains constructs encoding NTS-DBL1X, NTS-DBL1X-Id1, Id1, Id1-DBL2X and DBL2X were made and used to immunize mice. The NTS-DBL1X, NTS-DBL1X-Id1, and Id1-DBL2X fragments all raised high titer immune response, as measured by ELISA. The DBL2X fragment raised a weaker antibody titer, and the Id1 construct failed to elicit antibody. Sera from mice immunized with NTS-DBL1X or DBL2X constructs failed to block infected erythrocytes binding to CSA, whereas sera from mice immunized with NTS-DBL1X-Id1 showed partial inhibitory activity, and the Id1-DBL2X fragment elicited antisera that totally abrogated infected erythrocytes adhesion to CSA. IgG purified from Id1-DBL2X antisera showed a similar inhibitory profile than Id1-DBL2X antisera. Anti-FCR3 anti-Id1-DBL2X antibodies also efficiently block the adhesion of erythrocytes infected by the HB3 parasite line to CSA. Id1-DBL2X antisera recognized the surface of field isolates from pregnant women, and inhibited CSA-binding of all 8 isolates tested, although to a variable level. MAJOR CONCLUSIONS We raised high-titer antibodies against several parts of the protein, and identified Id1-DBL2X as the minimal VAR2CSA fragment inducing antibodies with CSA-binding inhibitory efficiency in the same range as the full-length extracellular part of VAR2CSA.
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Affiliation(s)
- Bita Bordbar
- Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France
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8
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Huynh BT, Fievet N, Gbaguidi G, Dechavanne S, Borgella S, Guézo-Mévo B, Massougbodji A, Ndam NT, Deloron P, Cot M. Influence of the timing of malaria infection during pregnancy on birth weight and on maternal anemia in Benin. Am J Trop Med Hyg 2011; 85:214-20. [PMID: 21813837 DOI: 10.4269/ajtmh.2011.11-0103] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Abstract. Although consequences of malaria in pregnancy are well known, the period of pregnancy in which infection has the highest impact is still unclear. In Benin, we followed up a cohort of 1,037 women through pregnancy until delivery. The objective was to evaluate the relationship between the timing of infection and birth weight, and maternal anemia at delivery. At the beginning of pregnancy, peripheral infections were associated with a decrease in mean birth weight (-98.5 g; P = 0.03) and an increase in the risk of anemia at delivery (adjusted odds ratio [aOR] = 1.6; P = 0.03). Infections in late pregnancy were related to a higher risk of maternal anemia at delivery (aOR = 1.7; P = 0.001). To fully protect the women during the whole pregnancy, already implemented measures (insecticide-treated nets and intermittent preventive treatment) should be reinforced. In the future, a vaccine against pregnancy-associated malaria parasites could protect the women in early pregnancy, which seems to be a high-risk period.
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Affiliation(s)
- Bich-Tram Huynh
- Institut de Recherche pour le Développement, Mère et Enfant Face aux Infections Tropicales, Paris, France.
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9
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Abstract
Vaccination is one of the most effective strategies employed to prevent morbidity and mortality from infectious diseases. Pregnancy is considered to be a time when women have consistent contact with their healthcare providers and it presents an opportunity for providers to review their immunization status and to advocate for appropriate vaccination antepartum and in the immediate postpartum period. All forms of immunization, with the exception of live viral or live bacterial vaccines are generally considered to be safe for administration during pregnancy. It is important that healthcare providers counsel pregnant women about the benefits of receiving the vaccines that are recommended during pregnancy as well as the potential risks to the developing fetus. It is imperative that obstetricians and primary care providers are aware of and implement the vaccination guidelines for women, both during pregnancy and in the postpartum period.
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Affiliation(s)
- Zain A Al-Safi
- Wayne State University School of Medicine Department of Obstetrics & Gynecology, 6071 West Outer Drive, Michigan, MI 48235, USA
| | - Valerie I Shavell
- Wayne State University School of Medicine Department of Obstetrics & Gynecology, 6071 West Outer Drive, Michigan, MI 48235, USA
| | - Bernard Gonik
- Wayne State University School of Medicine Department of Obstetrics & Gynecology, 6071 West Outer Drive, Michigan, MI 48235, USA
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10
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Guitard J, Andersen P, Ermont C, Gnidehou S, Fievet N, Lund O, Deloron P, Ndam NT. Plasmodium falciparum population dynamics in a cohort of pregnant women in Senegal. Malar J 2010; 9:165. [PMID: 20553578 PMCID: PMC2893538 DOI: 10.1186/1475-2875-9-165] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 06/16/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pregnant women acquire protective antibodies that cross-react with geographically diverse placental Plasmodium falciparum isolates, suggesting that surface molecules expressed on infected erythrocytes by pregnancy-associated malaria (PAM) parasites have conserved epitopes and, that designing a PAM vaccine may be envisaged. VAR2CSA is the main candidate for a pregnancy malaria vaccine, but vaccine development may be complicated by its sequence polymorphism. METHODS The dynamics of P. falciparum genotypes during pregnancy in 32 women in relation to VAR2CSA polymorphism and immunity was determined. The polymorphism of the msp2 gene and five microsatellites was analysed in consecutive parasite isolates, and the DBL5epsilon + Interdomain 5 (Id5) part of the var2csa gene of the corresponding samples was cloned and sequenced to measure variation. RESULTS In primigravidae, the multiplicity of infection in the placenta was associated with occurrence of low birth weight babies. Some parasite genotypes were able to persist over several weeks and, still be present in the placenta at delivery particularly when the host anti-VAR2CSA antibody level was low. Comparison of diversity among genotyping markers confirmed that some PAM parasites may harbour more than one var2csa gene copy in their genome. CONCLUSIONS Host immunity to VAR2CSA influences the parasite dynamics during pregnancy, suggesting that the acquisition of protective immunity requires pre-exposure to a limited number of parasite variants. Presence of highly conserved residues in surface-exposed areas of the VAR2CSA immunodominant DBL5epsilon domain, suggest its potential in inducing antibodies with broad reactivity.
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Affiliation(s)
- Juliette Guitard
- Institut de Recherche pour le Développement, Université Paris Descartes, France.
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11
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Garcia J, Curtidor H, Obando-Martinez AZ, Vizcaíno C, Pinto M, Martinez NL, Patarroyo MA, Patarroyo ME. Synthetic peptides from conserved regions of the Plasmodium falciparum early transcribed membrane and ring exported proteins bind specifically to red blood cell proteins. Vaccine 2009; 27:6877-86. [PMID: 19755146 DOI: 10.1016/j.vaccine.2009.09.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2009] [Revised: 08/25/2009] [Accepted: 09/01/2009] [Indexed: 12/01/2022]
Abstract
Severe malaria pathology is directly associated with cytoadherence of infected red blood cells (iRBCs) to healthy RBCs and/or endothelial cells occurring during the intraerythrocytic development of Plasmodium falciparum. We synthesized, as 20-mer long peptides, the members of the ring exported (REX) protein family encoded in chromosome 9, as well as the early transcribed membrane proteins (E-TRAMP) 10.2 and 4, to identify specific RBC binding regions in these proteins. Twelve binding peptides were identified (designated as HABPs): three were identified in REX1, two in REX2, one in REX3, two in REX4 and four in E-TRAMP 10.2. The majority of these HABPs was conserved among different P. falciparum strains, according to sequence analysis. No HABPs were found in E-TRAMP 4. Bindings of HABPs were saturable and sensitive to the enzymatic treatment of RBCs and HABPs had different structural features, according to circular dichroism studies. Our results suggest that the REX and E-TRAMP families participate in relevant interactions with RBC membrane proteins, which highlight these proteins as potential targets for the development of fully effective immunoprophylactic methods.
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Affiliation(s)
- Jeison Garcia
- Fundación Instituto de Inmunología de Colombia FIDIC, Carrera 50 No. 26-20, Bogotá, Colombia
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12
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Sander AF, Salanti A, Lavstsen T, Nielsen MA, Magistrado P, Lusingu J, Ndam NT, Arnot DE. Multiple var2csa-type PfEMP1 genes located at different chromosomal loci occur in many Plasmodium falciparum isolates. PLoS One 2009; 4:e6667. [PMID: 19690615 PMCID: PMC2723927 DOI: 10.1371/journal.pone.0006667] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 07/13/2009] [Indexed: 12/03/2022] Open
Abstract
Background The var2csa gene encodes a Plasmodium falciparum adhesion receptor which binds chondroitin sulfate A (CSA). This var gene is more conserved than other PfEMP1/var genes and is found in all P. falciparum isolates. In isolates 3D7, FCR3/It4 and HB3, var2csa is transcribed from a sub-telomeric position on the left arm of chromosome 12, but it is not known if this location is conserved in all parasites. Genome sequencing indicates that the var2csa gene is duplicated in HB3, but whether this is true in natural populations is uncertain. Methodology/Principal Findings To assess global variation in the VAR2CSA protein, sequence variation in the DBL2X region of var2csa genes in 54 P.falciparum samples was analyzed. Chromosome mapping of var2csa loci was carried out and a quantitative PCR assay was developed to estimate the number of var2csa genes in P.falciparum isolates from the placenta of pregnant women and from the peripheral circulation of other malaria patients. Sequence analysis, gene mapping and copy number quantitation in P.falciparum isolates indicate that there are at least two loci and that both var2csa-like genes can be transcribed. All VAR2CSA DBL2X domains fall into one of two distinct phylogenetic groups possessing one or the other variant of a large (∼26 amino acid) dimorphic motif, but whether either motif variant is linked to a specific locus is not known. Conclusions/Significance Two or more related but distinct var2csa-type PfEMP1/var genes exist in many P. falciparum isolates. One gene is on chromosome 12 but additional var2csa-type genes are on different chromosomes in different isolates. Multiplicity of var2csa genes appears more common in infected placentae than in samples from non-pregnant donors indicating a possible advantage of this genotype in pregnancy associated malaria.
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Affiliation(s)
- Adam F. Sander
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Ali Salanti
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Thomas Lavstsen
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Morten A. Nielsen
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Pamela Magistrado
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- JMP-ENRICA Project, National Institute for Medical Research, Korogwe Laboratory, Tanga, Tanzania
| | - John Lusingu
- JMP-ENRICA Project, National Institute for Medical Research, Korogwe Laboratory, Tanga, Tanzania
| | - Nicaise Tuikue Ndam
- Institut de Recherche pour le Developpment, UR010, Universite Paris Descartes, Paris, France
| | - David E. Arnot
- Centre for Medical Parasitology, Department of International Health, Immunology & Microbiology, Faculty of Health Sciences, University of Copenhagen & Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Institute of Immunology & Infection Research, School of Biology, University of Edinburgh, Edinburgh, Scotland, United Kingdom
- * E-mail:
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Abstract
The renewed interest in malaria research and control is based on the intolerable toll this disease takes on young children and pregnant women in Africa and other vulnerable populations; 150 to 300 children die each hour from malaria amounting to 1 to 2 million deaths yearly. Malaria-induced neurologic impairment, anemia, hypoglycemia, and low birth weight imperil normal development and survival. Resistance of Plasmodium falciparum to drugs and Anopheles mosquitoes to insecticides has stimulated discovery and development of artemisinin-based combination treatments (ACTs) and other drugs, long-lasting insecticide-treated bednets (with synthetic pyrethroids) and a search for non-toxic, long-lasting, affordable insecticides for indoor residual spraying (IRS). Malaria vaccine development and testing are progressing rapidly and a recombinant protein (RTS,S/AS02A) directed against the circumsporozoite protein is soon to be in Phase 3 trials. Support for malaria control, research, and advocacy through the Global Fund for HIV/AIDS, Tuberculosis and Malaria, the U.S. President's Malaria Initiative, the Bill & Melinda Gates Foundation, WHO and other organizations is resulting in decreasing morbidity and mortality in many malarious countries. Sustainability of effective programs through training and institution strengthening will be the key to malaria elimination coupled with improved surveillance and targeted research.
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Affiliation(s)
- Joel G Breman
- Fogarty International Center (FIC) of the US National Institutes of Health, Bethesda, Maryland 20892, USA.
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