1
|
Mahamar A, Traore M, Swihart B, Attaher O, Diarra BS, Santara G, Issiaka D, Barry A, Sidibé Y, Dicko YT, Keita S, Ndiaye O, Dicko A, Duffy PE, Fried M. Acquisition of antibodies that block Plasmodium falciparum adhesion to placental receptor chondroitin sulfate A with increasing gravidity in Malian women. Front Immunol 2024; 14:1330962. [PMID: 38274790 PMCID: PMC10808177 DOI: 10.3389/fimmu.2023.1330962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/20/2023] [Indexed: 01/27/2024] Open
Abstract
In malaria-endemic areas, pregnant women are more susceptible to Plasmodium falciparum infection, especially primigravidae. During pregnancy, parasites sequester in the placenta and bind to the receptor chondroitin sulfate (CSA). This unique adhesion is mediated by the parasite protein VAR2CSA expressed on the surface of infected erythrocytes (IE). Placental malaria is associated with poor pregnancy outcomes including perinatal mortality, preterm delivery, small for gestational age (SGA) and low birthweight deliveries. Over successive pregnancies, women acquire functional antibodies that inhibit IE adhesion to CSA. Here, we examine the development of anti-adhesion activity and the breadth of anti-adhesion activity as a function of number of previous pregnancies, using samples collected from pregnant women living in an area with high seasonal malaria transmission. Women reached plateau levels of anti-adhesion activity and breadth of anti-adhesion activity after 5 pregnancies. We related the level of anti-adhesion activity and reactivity with surface IE to SGA 19/232 pregnancies resulted in SGA, and report that an increase of 10% in median anti-adhesion activity reduced the odds of SGA by 13% and this relationship approached significance. Further, at an anti-adhesion activity level of 43.7%, an increase of 10% in the breadth of activity significantly reduced the odds of SGA by 21.5%. Antibodies that recognize IE surface increased over successive pregnancies, but were not associated with a reduction in SGA. These results can serve as a guideline for assessing vaccine candidates aiming to reduce poor pregnancy outcomes associated with placental malaria.
Collapse
Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Moussa Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, United States
| | - Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bacary Soumana Diarra
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Gaoussou Santara
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssoufa Sidibé
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Yahia T. Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Oulematou Ndiaye
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| |
Collapse
|
2
|
Doritchamou J, Nielsen MA, Chêne A, Viebig NK, Lambert LE, Sander AF, Semblat JP, Hundt S, Orr-Gonzalez S, Janitzek CM, Spiegel AJ, Clemmensen SB, Thomas ML, Nason MC, Snow-Smith M, Barnafo EK, Shiloach J, Chen BB, Nadakal S, Highsmith K, Ouahes T, Conteh S, Sharma A, Torano H, Butler B, Reiter K, Rausch KM, Scaria PV, Anderson C, Narum DL, Salanti A, Fried M, Theander TG, Gamain B, Duffy PE. Aotus nancymaae model predicts human immune response to the placental malaria vaccine candidate VAR2CSA. Lab Anim (NY) 2023; 52:315-323. [PMID: 37932470 PMCID: PMC10689237 DOI: 10.1038/s41684-023-01274-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 09/27/2023] [Indexed: 11/08/2023]
Abstract
Placental malaria vaccines (PMVs) are being developed to prevent severe sequelae of placental malaria (PM) in pregnant women and their offspring. The leading candidate vaccine antigen VAR2CSA mediates parasite binding to placental receptor chondroitin sulfate A (CSA). Despite promising results in small animal studies, recent human trials of the first two PMV candidates (PAMVAC and PRIMVAC) generated limited cross-reactivity and cross-inhibitory activity to heterologous parasites. Here we immunized Aotus nancymaae monkeys with three PMV candidates (PAMVAC, PRIMVAC and ID1-ID2a_M1010) adjuvanted with Alhydrogel, and exploited the model to investigate boosting of functional vaccine responses during PM episodes as well as with nanoparticle antigens. PMV candidates induced high levels of antigen-specific IgG with significant cross-reactivity across PMV antigens by enzyme-linked immunosorbent assay. Conversely, PMV antibodies recognized native VAR2CSA and blocked CSA adhesion of only homologous parasites and not of heterologous parasites. PM episodes did not significantly boost VAR2CSA antibody levels or serum functional activity; nanoparticle and monomer antigens alike boosted serum reactivity but not functional activities. Overall, PMV candidates induced functional antibodies with limited heterologous activity in Aotus monkeys, similar to responses reported in humans. The Aotus model appears suitable for preclinical downselection of PMV candidates and assessment of antibody boosting by PM episodes.
Collapse
Affiliation(s)
- Justin Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Morten A Nielsen
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Arnaud Chêne
- Université Paris Cité and Université des Antilles, INSERM, BIGR, Paris, France
| | - Nicola K Viebig
- European Vaccine Initiative, UniversitätsKlinikum Heidelberg, Heidelberg, Germany
| | - Lynn E Lambert
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Adam F Sander
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | | | - Sophia Hundt
- European Vaccine Initiative, UniversitätsKlinikum Heidelberg, Heidelberg, Germany
| | - Sachy Orr-Gonzalez
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Christoph Mikkel Janitzek
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Alicia J Spiegel
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | - Marvin L Thomas
- Division of Veterinary Resources, Office of Research Services, National Institutes of Health, Bethesda, MD, USA
| | - Martha C Nason
- Biostatistics Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Maryonne Snow-Smith
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Emma K Barnafo
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Joseph Shiloach
- Biotechnology Unit, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Beth B Chen
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Steven Nadakal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kendrick Highsmith
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Tarik Ouahes
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Solomon Conteh
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ankur Sharma
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Holly Torano
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Brandi Butler
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Karine Reiter
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kelly M Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Puthupparampil V Scaria
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ali Salanti
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Thor G Theander
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Benoit Gamain
- Université Paris Cité and Université des Antilles, INSERM, BIGR, Paris, France
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
3
|
Walker IS, Rogerson SJ. Pathogenicity and virulence of malaria: Sticky problems and tricky solutions. Virulence 2023; 14:2150456. [PMID: 36419237 PMCID: PMC9815252 DOI: 10.1080/21505594.2022.2150456] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 11/25/2022] Open
Abstract
Infections with Plasmodium falciparum and Plasmodium vivax cause over 600,000 deaths each year, concentrated in Africa and in young children, but much of the world's population remain at risk of infection. In this article, we review the latest developments in the immunogenicity and pathogenesis of malaria, with a particular focus on P. falciparum, the leading malaria killer. Pathogenic factors include parasite-derived toxins and variant surface antigens on infected erythrocytes that mediate sequestration in the deep vasculature. Host response to parasite toxins and to variant antigens is an important determinant of disease severity. Understanding how parasites sequester, and how antibody to variant antigens could prevent sequestration, may lead to new approaches to treat and prevent disease. Difficulties in malaria diagnosis, drug resistance, and specific challenges of treating P. vivax pose challenges to malaria elimination, but vaccines and other preventive strategies may offer improved disease control.
Collapse
Affiliation(s)
- Isobel S Walker
- Department of Infectious Diseases, The University of Melbourne, The Doherty Institute, Melbourne, Australia
| | - Stephen J Rogerson
- Department of Infectious Diseases, The University of Melbourne, The Doherty Institute, Melbourne, Australia
| |
Collapse
|
4
|
Kirosingh AS, Delmastro A, Kakuru A, van der Ploeg K, Bhattacharya S, Press KD, Ty M, Parte LDL, Kizza J, Muhindo M, Devachanne S, Gamain B, Nankya F, Musinguzi K, Rosenthal PJ, Feeney ME, Kamya M, Dorsey G, Jagannathan P. Malaria-specific Type 1 regulatory T cells are more abundant in first pregnancies and associated with placental malaria. EBioMedicine 2023; 95:104772. [PMID: 37634385 PMCID: PMC10474374 DOI: 10.1016/j.ebiom.2023.104772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/29/2023] Open
Abstract
BACKGROUND Malaria in pregnancy (MIP) causes higher morbidity in primigravid compared to multigravid women; however, the correlates and mechanisms underlying this gravidity-dependent protection remain incompletely understood. We aimed to compare the cellular immune response between primigravid and multigravid women living in a malaria-endemic region and assess for correlates of protection against MIP. METHODS We characterised the second trimester cellular immune response among 203 primigravid and multigravid pregnant women enrolled in two clinical trials of chemoprevention in eastern Uganda, utilizing RNA sequencing, flow cytometry, and functional assays. We compared responses across gravidity and determined associations with parasitaemia during pregnancy and placental malaria. FINDINGS Using whole blood RNA sequencing, no significant differentially expressed genes were identified between primigravid (n = 12) and multigravid (n = 11) women overall (log 2(FC) > 2, FDR < 0.1). However, primigravid (n = 49) women had higher percentages of malaria-specific, non-naïve CD4+ T cells that co-expressed IL-10 and IFNγ compared with multigravid (n = 85) women (p = 0.000023), and higher percentages of these CD4+ T cells were associated with greater risks of parasitaemia in pregnancy (Rs = 0.49, p = 0.001) and placental malaria (p = 0.0073). These IL-10 and IFNγ co-producing CD4+ T cells had a genomic signature of Tr1 cells, including expression of transcription factors cMAF and BATF and cell surface makers CTLA4 and LAG-3. INTERPRETATION Malaria-specific Tr1 cells were highly prevalent in primigravid Ugandan women, and their presence correlated with a higher risk of malaria in pregnancy. Understanding whether suppression of Tr1 cells plays a role in naturally acquired gravidity-dependent immunity may aid the development of new vaccines or treatments for MIP. FUNDING This work was funded by NIH (PO1 HD059454, U01 AI141308, U19 AI089674, U01 AI155325, U01 AI150741), the March of Dimes (Basil O'Connor award), and the Bill and Melinda Gates Foundation (OPP 1113682).
Collapse
Affiliation(s)
| | | | - Abel Kakuru
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | | | - Maureen Ty
- Stanford University School of Medicine, Stanford, USA
| | | | | | | | | | - Benoit Gamain
- Université Paris Cité, INSERM, BIGR, F-75014 Paris, France
| | | | | | | | | | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda; Makerere University, Kampala, Uganda
| | | | | |
Collapse
|
5
|
Fasanya A, Mohammed N, Saleh BH, Tijani MK, Teleka A, Quintana MDP, Hviid L, Persson KEM. Anti-phosphatidylserine antibody levels are low in multigravid pregnant women in a malaria-endemic area in Nigeria, and do not correlate with anti-VAR2CSA antibodies. Front Cell Infect Microbiol 2023; 13:1130186. [PMID: 37091678 PMCID: PMC10114609 DOI: 10.3389/fcimb.2023.1130186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Anemia is a common malaria-associated complication in pregnant women in endemic regions. Phosphatidylserine (PS) is exposed to the immune system during the massive destruction of red blood cells (RBCs) that accompany malaria, and antibodies against PS have been linked to anemia through destruction of uninfected RBCs. We determined levels of anti-PS IgG antibodies in pregnant women in Ibadan, Nigeria and correlated them to parameters of importance in development of anemia and immunity. Anti-PS correlated inversely with Packed Cell Volume (PCV), indicating that the antibodies could contribute to anemia. There was no correlation with anti-VAR2CSA IgG, haptoglobin or parasitemia, indicating that the modulation of anti-PS response is multifactorial in nature. Anti-PS levels were lowest in multigravidae compared to both primigravidae and secundigravidae and correlated inversely with age. In conclusion, lower levels of anti-PS in multigravidae could be beneficial in avoiding anemia.
Collapse
Affiliation(s)
- Adebimpe Fasanya
- Cellular Parasitology Programme, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - Nurat Mohammed
- Cellular Parasitology Programme, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - Bandar Hasan Saleh
- Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Skåne University Hospital, Lund University, Lund, Sweden
- Department of Medical Microbiology and Parasitology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Muyideen Kolapo Tijani
- Cellular Parasitology Programme, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
- Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Skåne University Hospital, Lund University, Lund, Sweden
- *Correspondence: Muyideen Kolapo Tijani, ; ; Kristina E. M. Persson,
| | - Alexandra Teleka
- Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Skåne University Hospital, Lund University, Lund, Sweden
| | - Maria del Pilar Quintana
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Hviid
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Kristina E. M. Persson
- Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Skåne University Hospital, Lund University, Lund, Sweden
- *Correspondence: Muyideen Kolapo Tijani, ; ; Kristina E. M. Persson,
| |
Collapse
|
6
|
Dharmaratne ADVTT, Dini S, O’Flaherty K, Price DJ, Beeson J, McGready R, Nosten F, Fowkes FJI, Simpson JA, Zaloumis SG. Quantification of the dynamics of antibody response to malaria to inform sero-surveillance in pregnant women. Malar J 2022; 21:75. [PMID: 35248084 PMCID: PMC8897879 DOI: 10.1186/s12936-022-04111-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 02/28/2022] [Indexed: 12/02/2022] Open
Abstract
Background Malaria remains a major public health threat and tools sensitive to detect infections in low malaria transmission areas are needed to progress elimination efforts. Pregnant women are particularly vulnerable to malaria infections. Throughout pregnancy they access routine antenatal care, presenting a unique sentinel population to apply novel sero-surveillance tools to measure malaria transmission. The aim of this study was to quantify the dynamic antibody responses to multiple antigens during pregnancy so as to identify a single or multiple antibody response of exposure to malaria in pregnancy. Methods This study involved a secondary analysis of antibody responses to six parasite antigens [five commonly studied merozoite antigens and the variant surface antigen 2-chondroitin sulphate A (VAR2CSA), a pregnancy-specific erythrocytic antigen] measured by enzyme-linked immunosorbent assay (ELISA) over the gestation period until delivery (median of 7 measurements/woman) in 250 pregnant women who attended antenatal clinics located at the Thai-Myanmar border. A multivariate mixture linear mixed model was used to cluster the pregnant women into groups that have similar longitudinal antibody responses to all six antigens over the gestational period using a Bayesian approach. The variable-specific entropy was calculated to identify the antibody responses that have the highest influence on the classification of the women into clusters, and subsequent agreement with grouping of women based on exposure to malaria during pregnancy. Results Of the 250 pregnant women, 135 had a Plasmodium infection detected by light microscopy during pregnancy (39% Plasmodium falciparum only, 33% Plasmodium vivax only and 28% mixed/other species), defined as cases. The antibody responses to all six antigens accurately identified the women who did not have a malaria infection detected during pregnancy (93%, 107/115 controls). Antibody responses to P. falciparum merozoite surface protein 3 (PfMSP3) and P. vivax apical membrane antigen 1 (PvAMA1) were the least dynamic. Antibody responses to the antigens P. falciparum apical membrane antigen 1 (PfAMA1) and PfVAR2CSA were able to identify the majority of the cases more accurately (63%, 85/135). Conclusion These findings suggest that the combination of antibodies, PfAMA1 and PfVAR2CSA, may be useful for sero-surveillance of malaria infections in pregnant women, particularly in low malaria transmission settings. Further investigation of other antibody markers is warranted considering these antibodies combined only detected 63% of the malaria infections during pregnancy. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04111-y.
Collapse
|
7
|
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.
Collapse
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.
| |
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Mortazavi SE, Lugaajju A, Kaddumukasa M, Tijani MK, Kironde F, Persson KEM. Osteopontin and malaria: no direct effect on parasite growth, but correlation with P. falciparum-specific B cells and BAFF in a malaria endemic area. BMC Microbiol 2021; 21:307. [PMID: 34742229 PMCID: PMC8571855 DOI: 10.1186/s12866-021-02368-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 10/26/2021] [Indexed: 11/30/2022] Open
Abstract
Background The dysregulation of B cell activation is prevalent during naturally acquired immunity against malaria. Osteopontin (OPN), a protein produced by various cells including B cells, is a phosphorylated glycoprotein that participates in immune regulation and has been suggested to be involved in the immune response against malaria. Here we studied the longitudinal concentrations of OPN in infants and their mothers living in Uganda, and how OPN concentrations correlated with B cell subsets specific for P. falciparum and B cell activating factor (BAFF). We also investigated the direct effect of OPN on P. falciparum in vitro. Results The OPN concentration was higher in the infants compared to the mothers, and OPN concentration in infants decreased from birth until 9 months. OPN concentration in infants during 9 months were independent of OPN concentrations in corresponding mothers. OPN concentrations in infants were inversely correlated with total atypical memory B cells (MBCs) as well as P. falciparum-specific atypical MBCs. There was a positive correlation between OPN and BAFF concentrations in both mothers and infants. When OPN was added to P. falciparum cultured in vitro, parasitemia was unaffected regardless of OPN concentration. Conclusions The concentrations of OPN in infants were higher and independent of the OPN concentrations in corresponding mothers. In vitro, OPN does not have a direct effect on P. falciparum growth. Our correlation analysis results suggest that OPN could have a role in the B cell immune response and acquisition of natural immunity against malaria. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02368-y.
Collapse
Affiliation(s)
- Susanne E Mortazavi
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden.,Department of Infectious Diseases, Skåne University Hospital, Lund, Sweden
| | - Allan Lugaajju
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden.,College of Health Sciences, Makerere University, Kampala, Uganda
| | - Mark Kaddumukasa
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Muyideen Kolapo Tijani
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden.,Cellular Parasitology Program, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - Fred Kironde
- Habib Medical School, Faculty of Health Sciences, Islamic University in Uganda, Kampala, Uganda
| | - Kristina E M Persson
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden.
| |
Collapse
|
10
|
Afucosylated Plasmodium falciparum-specific IgG is induced by infection but not by subunit vaccination. Nat Commun 2021; 12:5838. [PMID: 34611164 PMCID: PMC8492741 DOI: 10.1038/s41467-021-26118-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 09/11/2021] [Indexed: 01/02/2023] Open
Abstract
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family members mediate receptor- and tissue-specific sequestration of infected erythrocytes (IEs) in malaria. Antibody responses are a central component of naturally acquired malaria immunity. PfEMP1-specific IgG likely protects by inhibiting IE sequestration and through IgG-Fc Receptor (FcγR) mediated phagocytosis and killing of antibody-opsonized IEs. The affinity of afucosylated IgG to FcγRIIIa is up to 40-fold higher than fucosylated IgG, resulting in enhanced antibody-dependent cellular cytotoxicity. Most IgG in plasma is fully fucosylated, but afucosylated IgG is elicited in response to enveloped viruses and to paternal alloantigens during pregnancy. Here we show that naturally acquired PfEMP1-specific IgG is strongly afucosylated in a stable and exposure-dependent manner, and efficiently induces FcγRIIIa-dependent natural killer (NK) cell degranulation. In contrast, immunization with a subunit PfEMP1 (VAR2CSA) vaccine results in fully fucosylated specific IgG. These results have implications for understanding protective natural- and vaccine-induced immunity to malaria. Here, Larsen et al. describe differences in Fc fucosylation of P. falciparum PfEMP1-specific IgG produced in response to natural infection versus VAR2CSA-type subunit vaccination, which leads to differences in the ability to induce FcγRIIIa-dependent natural killer cell degranulation.
Collapse
|
11
|
Larsen MD, Lopez-Perez M, Dickson EK, Ampomah P, Tuikue Ndam N, Nouta J, Koeleman CAM, Ederveen ALH, Mordmüller B, Salanti A, Nielsen MA, Massougbodji A, van der Schoot CE, Ofori MF, Wuhrer M, Hviid L, Vidarsson G. Afucosylated Plasmodium falciparum-specific IgG is induced by infection but not by subunit vaccination. Nat Commun 2021. [PMID: 34611164 DOI: 10.1101/2021.04.23.441082v1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family members mediate receptor- and tissue-specific sequestration of infected erythrocytes (IEs) in malaria. Antibody responses are a central component of naturally acquired malaria immunity. PfEMP1-specific IgG likely protects by inhibiting IE sequestration and through IgG-Fc Receptor (FcγR) mediated phagocytosis and killing of antibody-opsonized IEs. The affinity of afucosylated IgG to FcγRIIIa is up to 40-fold higher than fucosylated IgG, resulting in enhanced antibody-dependent cellular cytotoxicity. Most IgG in plasma is fully fucosylated, but afucosylated IgG is elicited in response to enveloped viruses and to paternal alloantigens during pregnancy. Here we show that naturally acquired PfEMP1-specific IgG is strongly afucosylated in a stable and exposure-dependent manner, and efficiently induces FcγRIIIa-dependent natural killer (NK) cell degranulation. In contrast, immunization with a subunit PfEMP1 (VAR2CSA) vaccine results in fully fucosylated specific IgG. These results have implications for understanding protective natural- and vaccine-induced immunity to malaria.
Collapse
Affiliation(s)
- Mads Delbo Larsen
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands.,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Mary Lopez-Perez
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emmanuel Kakra Dickson
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Paulina Ampomah
- Department of Biomedical Sciences, School of Allied Health Sciences, University of Cape Coast, Cape Coast, Ghana
| | | | - Jan Nouta
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Carolien A M Koeleman
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Benjamin Mordmüller
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Ali Salanti
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Morten Agertoug Nielsen
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Achille Massougbodji
- Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d'Abomey-Calavi, Godomey, Benin
| | - C Ellen van der Schoot
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands.,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Michael F Ofori
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - 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, Rigshospitalet, Copenhagen, Denmark.
| | - Gestur Vidarsson
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands. .,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
| |
Collapse
|
12
|
Megli CJ, Coyne CB. Infections at the maternal-fetal interface: an overview of pathogenesis and defence. Nat Rev Microbiol 2021; 20:67-82. [PMID: 34433930 PMCID: PMC8386341 DOI: 10.1038/s41579-021-00610-y] [Citation(s) in RCA: 147] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2021] [Indexed: 02/08/2023]
Abstract
Infections are a major threat to human reproductive health, and infections in pregnancy can cause prematurity or stillbirth, or can be vertically transmitted to the fetus leading to congenital infection and severe disease. The acronym ‘TORCH’ (Toxoplasma gondii, other, rubella virus, cytomegalovirus, herpes simplex virus) refers to pathogens directly associated with the development of congenital disease and includes diverse bacteria, viruses and parasites. The placenta restricts vertical transmission during pregnancy and has evolved robust mechanisms of microbial defence. However, microorganisms that cause congenital disease have likely evolved diverse mechanisms to bypass these defences. In this Review, we discuss how TORCH pathogens access the intra-amniotic space and overcome the placental defences that protect against microbial vertical transmission. Infections during pregnancy can be associated with devastating outcomes for the pregnant mother and developing fetus. In this Review, Megli and Coyne discuss placental defences and provide an overview of how various viral, bacterial and parasitic pathogens traverse the maternal–fetal interface and cause disease.
Collapse
Affiliation(s)
- Christina J Megli
- Division of Maternal-Fetal Medicine, Division of Reproductive Infectious Disease, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine and the Magee Womens Research Institute, Pittsburgh, PA, USA.
| | - Carolyn B Coyne
- Department of Molecular Genetics and Microbiology and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA.
| |
Collapse
|
13
|
Aitken EH, Damelang T, Ortega-Pajares A, Alemu A, Hasang W, Dini S, Unger HW, Ome-Kaius M, Nielsen MA, Salanti A, Smith J, Kent S, Hogarth PM, Wines BD, Simpson JA, Chung AW, Rogerson SJ. Developing a multivariate prediction model of antibody features associated with protection of malaria-infected pregnant women from placental malaria. eLife 2021; 10:e65776. [PMID: 34181872 PMCID: PMC8241440 DOI: 10.7554/elife.65776] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 06/16/2021] [Indexed: 12/15/2022] Open
Abstract
Background Plasmodium falciparum causes placental malaria, which results in adverse outcomes for mother and child. P. falciparum-infected erythrocytes that express the parasite protein VAR2CSA on their surface can bind to placental chondroitin sulfate A. It has been hypothesized that naturally acquired antibodies towards VAR2CSA protect against placental infection, but it has proven difficult to identify robust antibody correlates of protection from disease. The objective of this study was to develop a prediction model using antibody features that could identify women protected from placental malaria. Methods We used a systems serology approach with elastic net-regularized logistic regression, partial least squares discriminant analysis, and a case-control study design to identify naturally acquired antibody features mid-pregnancy that were associated with protection from placental malaria at delivery in a cohort of 77 pregnant women from Madang, Papua New Guinea. Results The machine learning techniques selected 6 out of 169 measured antibody features towards VAR2CSA that could predict (with 86% accuracy) whether a woman would subsequently have active placental malaria infection at delivery. Selected features included previously described associations with inhibition of placental binding and/or opsonic phagocytosis of infected erythrocytes, and network analysis indicated that there are not one but multiple pathways to protection from placental malaria. Conclusions We have identified candidate antibody features that could accurately identify malaria-infected women as protected from placental infection. It is likely that there are multiple pathways to protection against placental malaria. Funding This study was supported by the National Health and Medical Research Council (Nos. APP1143946, GNT1145303, APP1092789, APP1140509, and APP1104975).
Collapse
Affiliation(s)
- Elizabeth H Aitken
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Timon Damelang
- Department of Microbiology and Immunology, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Amaya Ortega-Pajares
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Agersew Alemu
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Wina Hasang
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Saber Dini
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of MelbourneMelbourneAustralia
| | - Holger W Unger
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
- Department of Obstetrics and Gynaecology, Royal Darwin HospitalDarwinAustralia
- Menzies School of Health ResearchDarwinAustralia
| | - Maria Ome-Kaius
- Walter and Eliza Hall Institute of Medical ResearchParkvilleAustralia
| | - Morten A Nielsen
- Centre for Medical Parasitology, Department of Microbiology and immunology, University of CopenhagenCopenhagenDenmark
| | - Ali Salanti
- Centre for Medical Parasitology, Department of Microbiology and immunology, University of CopenhagenCopenhagenDenmark
- Department of Infectious Disease, Copenhagen University HospitalCopenhagenDenmark
| | - Joe Smith
- Seattle Children’s Research InstituteSeattleUnited States
- Department of Pediatrics, University of WashingtonSeattleUnited States
| | - Stephen Kent
- Department of Microbiology and Immunology, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - P Mark Hogarth
- Seattle Children’s Research InstituteSeattleUnited States
- Immune Therapies Group, Centre for Biomedical Research, Burnet InstituteMelbourneAustralia
- Department of Clinical Pathology, University of MelbourneMelbourneAustralia
- Department of Immunology and Pathology, Monash UniversityMelbourneAustralia
| | - Bruce D Wines
- Immune Therapies Group, Centre for Biomedical Research, Burnet InstituteMelbourneAustralia
- Department of Clinical Pathology, University of MelbourneMelbourneAustralia
- Department of Immunology and Pathology, Monash UniversityMelbourneAustralia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of MelbourneMelbourneAustralia
| | - Amy W Chung
- Department of Microbiology and Immunology, University of Melbourne, the Doherty InstituteMelbourneAustralia
| | - Stephen J Rogerson
- Department of Medicine, University of Melbourne, the Doherty InstituteMelbourneAustralia
| |
Collapse
|
14
|
McLean ARD, Opi DH, Stanisic DI, Cutts JC, Feng G, Ura A, Mueller I, Rogerson SJ, Beeson JG, Fowkes FJI. High Antibodies to VAR2CSA in Response to Malaria Infection Are Associated With Improved Birthweight in a Longitudinal Study of Pregnant Women. Front Immunol 2021; 12:644563. [PMID: 34220804 PMCID: PMC8242957 DOI: 10.3389/fimmu.2021.644563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 05/17/2021] [Indexed: 11/23/2022] Open
Abstract
Introduction Pregnant women have an increased risk of P. falciparum infection, which is associated with low birth weight and preterm delivery. VAR2CSA, a variant surface antigen expressed on the parasitized erythrocyte surface, enables sequestration in the placenta. Few studies have prospectively examined relationships between antibody responses during pregnancy and subsequent adverse birth outcomes, and there are limited data outside Africa. Methods Levels of IgG against VAR2CSA domains (DBL3; DBL5) and a VAR2CSA-expressing placental-binding P. falciparum isolate (PfCS2-IE) were measured in 301 women enrolled at their first visit to antenatal care which occurred mid-pregnancy (median = 26 weeks, lower and upper quartiles = 22, 28). Associations between antibody levels at enrolment and placental infection, birthweight and estimated gestational age at delivery were assessed by linear and logistic regression with adjustment for confounders. For all outcomes, effect modification by gravidity and peripheral blood P. falciparum infection at enrolment was assessed. Results Among women who had acquired P. falciparum infection at enrolment, those with higher levels of VAR2CSA antibodies (75th percentile) had infants with higher mean birthweight (estimates varied from +35g to +149g depending on antibody response) and reduced adjusted odds of placental infection (aOR estimates varied from 0.17 to 0.80), relative to women with lower levels (25th percentile) of VAR2CSA antibodies. However, among women who had not acquired an infection at enrolment, higher VAR2CSA antibodies were associated with increased odds of placental infection (aOR estimates varied from 1.10 to 2.24). Conclusions When infected by mid-pregnancy, a better immune response to VAR2CSA-expressing parasites may contribute to protecting against adverse pregnancy outcomes.
Collapse
Affiliation(s)
- Alistair R D McLean
- Burnet Institute, Melbourne, VIC, Australia.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - D Herbert Opi
- Burnet Institute, Melbourne, VIC, Australia.,Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia.,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Danielle I Stanisic
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Institute for Glycomics, Griffith University, Southport, QLD, Australia
| | - Julia C Cutts
- Burnet Institute, Melbourne, VIC, Australia.,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Gaoqian Feng
- Burnet Institute, Melbourne, VIC, Australia.,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Alice Ura
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Ivo Mueller
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Population, Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Département Parasites et Insectes Vecteurs, Institute Pasteur, Paris, France
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, VIC, Australia.,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, VIC, Australia.,Department of Microbiology, Monash University, Clayton, VIC, Australia
| | - Freya J I Fowkes
- Burnet Institute, Melbourne, VIC, Australia.,Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Centre for Epidemiology and Biostatistics, University of Melbourne, Melbourne, VIC, Australia.,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| |
Collapse
|
15
|
Abstract
Maria del Pilar Quintana works on immunology and pathogenesis of severe malaria. In this mSphere of Influence article, she reflects on how the papers "Structural basis for placental malaria mediated by Plasmodium falciparum VAR2CSA" (R. Ma, T. Lian, R. Huang, J. P. Renn, J. D. Petersen, J. Zimmerberg, P. E. Duffy, N. H. Tolia, Nat Microbiol 6:380-391, 2021, https://doi.org/10.1038/s41564-020-00858-9) and "Cryo-EM reveals the architecture of placental malaria VAR2CSA and provides molecular insight into chondroitin sulfate binding" (K. Wang, R. Dagil, T. Lavsten, S. K. Misra, C. B. Spliid, Y. Wang, T. Gustavsson, D. R. Sandoval, E. E. Vidal-Calvo, S. Choudary, M. O. Agerback, K. Lindorff-Larsen, M. A. Nielsen, T. G. Theander, J. S. Sharp, T. M. Clausen, P. Gourdon, A. Salanti, A. Salanti, Nat Commun 12:2956, 2021, https://doi.org/10.1038/s41467-021-23254-1) shed light on the precise structural details behind Plasmodium falciparum VAR2CSA binding to chondroitin sulfate A (CSA) in the placenta and how these novel insights have changed the way she will approach her work toward the discovery of new broadly cross-reactive/inhibitory antibodies targeting VAR2CSA.
Collapse
|
16
|
Dombrowski JG, Barateiro A, Peixoto EPM, Barros ABCDS, de Souza RM, Clark TG, Campino S, Wrenger C, Wunderlich G, Palmisano G, Epiphanio S, Gonçalves LA, Marinho CRF. Adverse pregnancy outcomes are associated with Plasmodium vivax malaria in a prospective cohort of women from the Brazilian Amazon. PLoS Negl Trop Dis 2021; 15:e0009390. [PMID: 33914739 PMCID: PMC8112668 DOI: 10.1371/journal.pntd.0009390] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 05/11/2021] [Accepted: 04/15/2021] [Indexed: 11/29/2022] Open
Abstract
Background Malaria in Brazil represents one of the highest percentages of Latin America cases, where approximately 84% of infections are attributed to Plasmodium (P.) vivax. Despite the high incidence, many aspects of gestational malaria resulting from P. vivax infections remain poorly studied. As such, we aimed to evaluate the consequences of P. vivax infections during gestation on the health of mothers and their neonates in an endemic area of the Amazon. Methods and findings We have conducted an observational cohort study in Brazilian Amazon between January 2013 and April 2015. 600 pregnant women were enrolled and followed until delivery. After applying exclusion criteria, 329 mother-child pairs were included in the analysis. Clinical data regarding maternal infection, newborn’s anthropometric measures, placental histopathological characteristics, and angiogenic and inflammatory factors were evaluated. The presence of plasma IgG against the P. vivax (Pv) MSP119 protein was used as marker of exposure and possible associations with pregnancy outcomes were analyzed. Multivariate logistic regression analysis revealed that P. vivax infections during the first trimester of pregnancy are associated with adverse gestational outcomes such as premature birth (adjusted odds ratio [aOR] 8.12, 95% confidence interval [95%CI] 2.69–24.54, p < 0.0001) and reduced head circumference (aOR 3.58, 95%CI 1.29–9.97, p = 0.01). Histopathology analysis showed marked differences between placentas from P. vivax-infected and non-infected pregnant women, especially regarding placental monocytes infiltrate. Placental levels of vasomodulatory factors such as angiopoietin-2 (ANG-2) and complement proteins such as C5a were also altered at delivery. Plasma levels of anti-PvMSP119 IgG in infected pregnant women were shown to be a reliable exposure marker; yet, with no association with improved pregnancy outcomes. Conclusions This study indicates that P. vivax malaria during the first trimester of pregnancy represents a higher likelihood of subsequent poor pregnancy outcomes associated with marked placental histologic modification and angiogenic/inflammatory imbalance. Additionally, our findings support the idea that antibodies against PvMSP119 are not protective against poor pregnancy outcomes induced by P. vivax infections. Malaria during pregnancy is associated with adverse effects on the fetus and the newborn. As far as we know, no study has previously investigated in a single work, the link between Plasmodium vivax malaria in pregnancy and poor gestational outcomes, alteration of the newborn’s anthropometric profile, placental lesions, angiogenic and inflammatory factors, and humoral immunity against the parasite. For this purpose, we investigated the association between P. vivax malaria during pregnancy and newborn’s anthropometric profile, placental pathology, gestational outcomes, and the presence of IgG against P. vivax MSP119 that may confer protection against infection during pregnancy. We performed a large cohort study of malaria during pregnancy that analyzed data from mother-child pairs delivered between 2013 and 2015 in the Southwestern Brazilian Amazonian region. By evaluating data from 329 pregnancies, we found that P. vivax malaria during the first pregnancy trimester is significantly associated with the occurrence of preterm birth, low birth weight, and reduced newborn head circumference and body length. We also noted that P. vivax malaria in pregnancy promoted placental lesions and homeostasis imbalance, characterized by increased syncytial nuclear aggregates, fibrin deposition, and monocytes/leukocytes infiltrate, as well as imbalanced angiogenic factors, leptin, and cytokines. We observed that pregnant women with IgG against P. vivax MSP119 are not protected against poor pregnancy outcomes caused by P. vivax infections during pregnancy. Our observations improve our understanding of the disease and P. vivax burden during pregnancy, changing the current paradigm of the outcome of P. vivax malaria in pregnancy. That may represent a long-term severe consequence for the affected populations living in P. vivax-endemic regions. Our results also indicate that IgG against P. vivax MSP119 is not associated with protection from poor pregnancy outcomes, excluding this protein as a possible vaccination target that can prevent adverse outcomes caused by P. vivax infections during pregnancy.
Collapse
Affiliation(s)
| | - André Barateiro
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | | | | | - Taane Gregory Clark
- Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Susana Campino
- Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Carsten Wrenger
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gerhard Wunderlich
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Giuseppe Palmisano
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Sabrina Epiphanio
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Lígia Antunes Gonçalves
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- * E-mail: (LAG); (CRFM)
| | - Claudio Romero Farias Marinho
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- * E-mail: (LAG); (CRFM)
| |
Collapse
|
17
|
Vanda K, Bobbili N, Matsunaga M, Chen JJ, Salanti A, Leke RFG, Taylor DW. The Development, Fine Specificity, and Importance of High-Avidity Antibodies to VAR2CSA in Pregnant Cameroonian Women Living in Yaoundé, an Urban City. Front Immunol 2021; 12:610108. [PMID: 33717094 PMCID: PMC7953046 DOI: 10.3389/fimmu.2021.610108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 01/07/2021] [Indexed: 11/25/2022] Open
Abstract
Pregnant women infected with Plasmodium falciparum often produce antibodies (Abs) to VAR2CSA, a ligand that binds to placental chondroitin sulfate A causing placental malaria (PM). Antibodies to VAR2CSA are associated with improved pregnancy outcomes. Antibody avidity is a surrogate marker for the extent of maturation of the humoral immune response. Little is known about high avidity Abs to VAR2CSA for women living in urban African cities. Therefore, this study sought to determine: i) if high avidity Abs to full-length VAR2CSA (FV2) increase with gravidity in women in Yaoundé, Cameroon exposed to ~ 0.3-1.1 infectious mosquito bites per month, ii) if high avidity Abs to FV2 are directed against a specific region of VAR2CSA, and iii) if having high avidity Abs to FV2 improve pregnancy outcomes. Plasma samples collected at delivery from 695 women who had Abs to FV2 were evaluated. Ab levels and the Avidity Index (AI), defined as the percent Abs remaining bound to FV2 after incubation with 3M NH4SCN, were determined. Similar Ab levels to FV2 were present in women of all gravidities (G1 through 6+; p=0.80), except significantly lower levels were detected in PM−negative (PM−) primigravidae (p <0.001). Median Ab avidities increased between gravidity 1 and 2 (p<0.001) and remained stable thereafter (G3-G6+: p=0.51). These results suggest that B cell clonal expansion began during the first pregnancy, with clonal selection primarily occurring during the second. However, the majority of women (84%) had AI <35, a level of high avidity Abs previously reported to be associated with improved pregnancy outcomes. When plasma from 107 Cameroonian women was tested against 8 different regions of FV2, high avidity Abs were predominately restricted to DBL5 with median AI of 50 compared to AI <25 for the other domains. The only significance influence of high avidity Abs on pregnancy outcome was that babies born to mothers with AI above the median were 104 g heavier than babies born to women with AI below the median (p=0.045). These results suggest that a vaccine that boosts maturation of the immune response to VAR2CSA may be beneficial for women residing in urban areas.
Collapse
Affiliation(s)
- Koko Vanda
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Naveen Bobbili
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Masako Matsunaga
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - John J Chen
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Ali Salanti
- Centre for Medical Parasitology, Department for Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen and Department of Infectious Disease, Copenhagen University Hospital, Copenhagen, Denmark
| | - Rose F G Leke
- Faculty of Medicine and Biomedical Research, The Biotechnology Center, University of Yaoundé 1, Yaoundé, Cameroon
| | - Diane Wallace Taylor
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| |
Collapse
|
18
|
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.
Collapse
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
| |
Collapse
|
19
|
Rönnberg C, Lugaajju A, Nyman A, Hammar U, Bottai M, Lautenbach MJ, Sundling C, Kironde F, Persson KEM. A longitudinal study of plasma BAFF levels in mothers and their infants in Uganda, and correlations with subsets of B cells. PLoS One 2021; 16:e0245431. [PMID: 33465125 PMCID: PMC7815132 DOI: 10.1371/journal.pone.0245431] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 01/03/2021] [Indexed: 01/05/2023] Open
Abstract
Malaria is a potentially life-threatening disease with approximately half of the world’s population at risk. Young children and pregnant women are hit hardest by the disease. B cells and antibodies are part of an adaptive immune response protecting individuals continuously exposed to the parasite. An infection with Plasmodium falciparum can cause dysregulation of B cell homeostasis, while antibodies are known to be key in controlling symptoms and parasitemia. BAFF is an instrumental cytokine for the development and maintenance of B cells. Pregnancy alters the immune status and renders previously clinically immune women at risk of severe malaria, potentially due to altered B cell responses associated with changes in BAFF levels. In this prospective study, we investigated the levels of BAFF in a malaria-endemic area in mothers and their infants from birth up to 9 months. We found that BAFF-levels are significantly higher in infants than in mothers. BAFF is highest in cord blood and then drops rapidly, but remains significantly higher in infants compared to mothers even at 9 months of age. We further correlated BAFF levels to P. falciparum-specific antibody levels and B cell frequencies and found a negative correlation between BAFF and both P. falciparum-specific and total proportions of IgG+ memory B cells, as well as CD27− memory B cells, indicating that exposure to both malaria and other diseases affect the development of B-cell memory and that BAFF plays a part in this. In conclusion, we have provided new information on how natural immunity against malaria is formed.
Collapse
Affiliation(s)
- Caroline Rönnberg
- Department of Microbiology, Tumor, and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Division of Infectious Diseases, Department of Medicine Solna, and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Allan Lugaajju
- Department of Microbiology, Tumor, and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Makerere University, Kampala, Uganda
| | - Anna Nyman
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden
| | - Ulf Hammar
- Division of Biostatistics, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Matteo Bottai
- Division of Biostatistics, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Maximilian Julius Lautenbach
- Division of Infectious Diseases, Department of Medicine Solna, and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Christopher Sundling
- Division of Infectious Diseases, Department of Medicine Solna, and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Fred Kironde
- Makerere University, Kampala, Uganda
- Habib Medical School, Islamic University in Uganda (IUIU), Mbale, Uganda
| | - Kristina E. M. Persson
- Department of Laboratory Medicine, Lund University, Skåne University Hospital, Lund, Sweden
- * E-mail:
| |
Collapse
|
20
|
Wiebe MC, Yanow SK. Do Antibodies to Malaria Surface Antigens Play a Role in Protecting Mothers From Maternal Anemia? Front Immunol 2020; 11:609957. [PMID: 33391279 PMCID: PMC7775498 DOI: 10.3389/fimmu.2020.609957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/17/2020] [Indexed: 11/13/2022] Open
Abstract
Pregnancy-associated malaria (PAM) caused by Plasmodium falciparum can result in detrimental outcomes for both mother and infant, including low infant birth weight, preterm birth, maternal anemia, spontaneous abortion, and maternal and/or infant mortality. Maternal anemia is a particularly complex outcome, as the body must both maintain erythropoiesis and tolerance of the growing fetus, while directing a Th1 response against the parasite. Underlying the pathogenesis of PAM is the expression of variant surface antigens (VSAPAM) on the surface of infected red blood cells (iRBC) that mediate sequestration of the iRBC in the placenta. Naturally acquired antibodies to VSAPAM can block sequestration and activate opsonic phagocytosis, both associated with improved pregnancy outcomes. In this review, we ask whether VSAPAM antibodies can also protect mothers against malarial anemia. Studies were identified where VSAPAM antibody titres and/or function were associated with higher maternal hemoglobin levels, thus supporting additional protective mechanisms for these antibodies against PAM. Yet these associations were not widely observed, and many studies reported no association between protection from maternal anemia and VSAPAM antibodies. We discuss the epidemiological, biological and technical factors that may explain some of the variability among these studies. We appraise the current evidence of these complex interactions between PAM-specific immunity and maternal anemia, propose potential mechanisms, and discuss knowledge gaps.
Collapse
Affiliation(s)
- Madeleine C Wiebe
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Stephanie K Yanow
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,School of Public Health, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
21
|
Kalinjuma AV, Darling AM, Mugusi FM, Abioye AI, Okumu FO, Aboud S, Masanja H, Hamer DH, Hertzmark E, Fawzi WW. Factors associated with sub-microscopic placental malaria and its association with adverse pregnancy outcomes among HIV-negative women in Dar es Salaam, Tanzania: a cohort study. BMC Infect Dis 2020; 20:796. [PMID: 33109111 PMCID: PMC7590608 DOI: 10.1186/s12879-020-05521-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 10/16/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria infection during pregnancy has negative health consequences for both mothers and offspring. Sub-microscopic malaria infection during pregnancy is common in most African countries. We sought to identify factors associated with sub-microscopic placental malaria, and its association with adverse pregnancy outcomes among HIV-negative pregnant women in Dar es Salaam, Tanzania. METHODS We recruited a cohort of pregnant women during their first trimester and assessed for the occurrence of placental malaria and pregnancy outcomes. The follow-up was done monthly from recruitment until delivery. Histopathology placental malaria positive results were defined as the presence of malaria pigment or parasitized erythrocytes on the slide (histology-positive (HP)), and the sub-microscopic placental infection was defined as positive Plasmodium falciparum DNA by polymerase chain reaction (DNA PCR) amplification in a negative histopathology test. Adverse pregnancy outcomes investigated included low birth weight (birth weight below 2.5 kg), prematurity (live birth below 37 weeks), and small-for-gestational-age (SGA) (live born with a birth weight below 10th percentile for gestational age and sex). Weighted baseline category logit, log-binomial, and log-Poisson models were used to assess factors associated with placental malaria, and its association with adverse pregnancy outcomes. RESULTS Among 1115 women who had histopathology and DNA PCR performed, 93 (8%) had HP placental infection, and 136 (12%) had the sub-microscopic placental infection. The risk of sub-microscopic placental malaria was greater in women who did not use mosquito prevention methods such as bed nets, fumigation, or mosquito coils (odds ratio (OR) = 1.75; 95% confidence interval (CI): 1.05-2.92; P = 0.03) and in women who were anemic (OR = 1.59; 95% CI: 1.20-2.11; P = 0.001). Women who were underweight had reduced odds of sub-microscopic placental malaria infection (OR = 0.33; 95% CI: 0.17-0.62; P = 0.001). Women who were overweight/obese had 1.48 times higher the odds of HP placental malaria compared to normal weight (OR = 1.48; 95% CI: 1.03-2.11; P = 0.03). HP placental malaria infection was associated with an increased risk of SGA births (RR = 1.30, 95% CI: 0.98-1.72, P = 0.07). In contrast, the sub-microscopic infection was associated with a reduced risk of SGA births (RR = 0.61, 95% CI: 0.43-0.88, P = 0.01). Placental malaria was not associated with low birth weight or prematurity. CONCLUSION Malaria prevention methods and maternal nutrition status during early pregnancy were important predictors of sub-microscopic placental malaria. More research is needed to understand sub-microscopic placental malaria and the possible mechanisms mediating the association between placental malaria and SGA.
Collapse
Affiliation(s)
- Aneth Vedastus Kalinjuma
- Department of Intervention and Clinical Trials, Ifakara Health Institute, P.O. Box 53, Ifakara, Morogoro, Tanzania.
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
| | - Anne Marie Darling
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Ferdinand M Mugusi
- Departments of Internal Medicine; and Microbiology and Immunology, School of Medicine, Muhimbili University of Health and Allied Sciences, Dar-es-Salaam, Tanzania
| | - Ajibola Ibraheem Abioye
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Fredros O Okumu
- Department of Intervention and Clinical Trials, Ifakara Health Institute, P.O. Box 53, Ifakara, Morogoro, Tanzania
| | - Said Aboud
- Departments of Internal Medicine; and Microbiology and Immunology, School of Medicine, Muhimbili University of Health and Allied Sciences, Dar-es-Salaam, Tanzania
| | - Honorati Masanja
- Department of Intervention and Clinical Trials, Ifakara Health Institute, P.O. Box 53, Ifakara, Morogoro, Tanzania
| | - Davidson H Hamer
- Department of Global Health, Boston University School of Public Health, Boston, MA, USA
- Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Ellen Hertzmark
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Wafaie W Fawzi
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| |
Collapse
|
22
|
Gnidehou S, Yanow SK. VAR2CSA Antibodies in Non-Pregnant Populations. Trends Parasitol 2020; 37:65-76. [PMID: 33067131 DOI: 10.1016/j.pt.2020.09.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/18/2022]
Abstract
The Plasmodium falciparum protein VAR2CSA is a critical mediator of placental malaria, and VAR2CSA antibodies (IgGs) are important to protect pregnant women. Although infrequently detected outside pregnancy, VAR2CSA IgGs were reported in men and children from Colombia and Brazil and in select African populations. These findings raise questions about the specificity of VAR2CSA IgGs and the mechanisms by which they are acquired outside pregnancy. Here we review the data on VAR2CSA IgGs in men and children from different malaria-endemic regions. We discuss experimental factors that may affect interpretation of the serological data and consider the biological relevance of VAR2CSA IgGs in non-pregnant populations. We propose potential mechanisms for the acquisition of VARCSA IgGs outside of pregnancy. We identify knowledge gaps and research priorities.
Collapse
Affiliation(s)
- Sedami Gnidehou
- Campus Saint-Jean, University of Alberta, Edmonton, AB, Canada; Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
| | - Stephanie K Yanow
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada; School of Public Health, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
23
|
Antibodies to full-length and the DBL5 domain of VAR2CSA in pregnant women after long-term implementation of intermittent preventive treatment in Etoudi, Cameroon. PLoS One 2020; 15:e0237671. [PMID: 32797068 PMCID: PMC7428160 DOI: 10.1371/journal.pone.0237671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/30/2020] [Indexed: 12/02/2022] Open
Abstract
In high malaria transmission settings, the use of sulfadoxine-pyrimethamine-based intermittent preventive treatment during pregnancy (IPTp-SP) has resulted in decreased antibody (Ab) levels to VAR2CSA. However, information of Ab levels in areas of low or intermediate malaria transmission after long-term implementation of IPTp-SP is still lacking. The present study sought to evaluate antibody prevalence and levels in women at delivery in Etoudi, a peri-urban area in the capital of Yaoundé, Cameroon, that is a relatively low-malaria transmission area. Peripheral plasma samples from 130 pregnant women were collected at delivery and tested for IgG to the full-length recombinant VAR2CSA (FV2) and its most immunogenic subdomain, DBL5. The study was conducted between 2013 and 2015, approximately ten years after implementation of IPTp-SP in Cameroon. About 8.6% of the women attending the clinic had placental malaria (PM). One, two or 3 doses of SP did not impact significantly on either the percentage of women with Ab to FV2 and DBL5 or Ab levels in Ab-positive women compared to women not taking SP. The prevalence of Ab to FV2 and DBL5 was only 36.9% and 36.1%, respectively. Surprisingly, among women who had PM at delivery, only 61.5% and 57.7% had Ab to FV2 and DBL5, respectively, with only 52.9% and 47.1% in PM-positive paucigravidae and 77.7% of multigravidae having Ab to both antigens. These results suggest that long-term implementation of IPTp-SP in a low-malaria transmission area results in few women having Ab to VAR2CSA.
Collapse
|
24
|
van der Puije W, Wang CW, Sudharson S, Hempel C, Olsen RW, Dalgaard N, Ofori MF, Hviid L, Kurtzhals JAL, Staalsoe T. In vitro selection for adhesion of Plasmodium falciparum-infected erythrocytes to ABO antigens does not affect PfEMP1 and RIFIN expression. Sci Rep 2020; 10:12871. [PMID: 32732983 PMCID: PMC7393120 DOI: 10.1038/s41598-020-69666-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 07/09/2020] [Indexed: 11/09/2022] Open
Abstract
Plasmodium falciparum causes the most severe form of malaria in humans. The adhesion of the infected erythrocytes (IEs) to endothelial receptors (sequestration) and to uninfected erythrocytes (rosetting) are considered major elements in the pathogenesis of the disease. Both sequestration and rosetting appear to involve particular members of several IE variant surface antigens (VSAs) as ligands, interacting with multiple vascular host receptors, including the ABO blood group antigens. In this study, we subjected genetically distinct P. falciparum parasites to in vitro selection for increased IE adhesion to ABO antigens in the absence of potentially confounding receptors. The selection resulted in IEs that adhered stronger to pure ABO antigens, to erythrocytes, and to various human cell lines than their unselected counterparts. However, selection did not result in marked qualitative changes in transcript levels of the genes encoding the best-described VSA families, PfEMP1 and RIFIN. Rather, overall transcription of both gene families tended to decline following selection. Furthermore, selection-induced increases in the adhesion to ABO occurred in the absence of marked changes in immune IgG recognition of IE surface antigens, generally assumed to target mainly VSAs. Our study sheds new light on our understanding of the processes and molecules involved in IE sequestration and rosetting.
Collapse
Affiliation(s)
- William van der Puije
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana.,Centre for Medical Parasitology, Department of Clinical Microbiology, Rigshospitalet, Ole Maaløes Vej, 7602, 2200, Copenhagen, Denmark
| | - Christian W Wang
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Srinidhi Sudharson
- Centre for Medical Parasitology, Department of Clinical Microbiology, Rigshospitalet, Ole Maaløes Vej, 7602, 2200, Copenhagen, Denmark
| | - Casper Hempel
- Centre for Medical Parasitology, Department of Clinical Microbiology, Rigshospitalet, Ole Maaløes Vej, 7602, 2200, Copenhagen, Denmark
| | - Rebecca W Olsen
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nanna Dalgaard
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael F Ofori
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Lars Hviid
- Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark.,Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen A L Kurtzhals
- Centre for Medical Parasitology, Department of Clinical Microbiology, Rigshospitalet, Ole Maaløes Vej, 7602, 2200, Copenhagen, Denmark.,Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Trine Staalsoe
- Centre for Medical Parasitology, Department of Clinical Microbiology, Rigshospitalet, Ole Maaløes Vej, 7602, 2200, Copenhagen, Denmark. .,Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
25
|
Acquah FK, Lo AC, Akyea-Mensah K, Abagna HB, Faye B, Theisen M, Gyan BA, Amoah LE. Stage-specific Plasmodium falciparum immune responses in afebrile adults and children living in the Greater Accra Region of Ghana. Malar J 2020; 19:64. [PMID: 32041620 PMCID: PMC7011432 DOI: 10.1186/s12936-020-3146-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/30/2020] [Indexed: 12/02/2022] Open
Abstract
Background Asymptomatic carriage of Plasmodium falciparum is widespread in adults and children living in malaria-endemic countries. This study identified the prevalence of malaria parasites and the corresponding levels of naturally acquired anti-parasite antibody levels in afebrile adults living in two communities in the Greater Accra Region of Ghana. Methods Two cross-sectional studies conducted in January and February 2016 and repeated in July and August 2016 recruited subjects aged between 6 and 75 years from high parasite prevalence (Obom) and low parasite prevalence (Asutsuare) communities. Whole blood (5 ml) was collected from each volunteer, plasma was aliquoted and frozen until needed. An aliquot (10 µl) of the blood was used to prepare thick and thin blood smears, 100 µl was preserved in Trizol and the rest was separated into plasma and blood cells and each stored at − 20 °C until needed. Anti-MSP3 and Pfs230 antibody levels were measured using ELISA. Results Asexual parasite and gametocyte prevalence were higher in Obom than Asutsuare. Antibody (IgG, IgG1, IgG3, IgM) responses against the asexual parasite antigen MSP3 and gametocyte antigen Pfs230 were higher in Obom during the course of the study except for IgM responses against Pfs230, which was higher in Asutsuare than in Obom during the rainy season. Antibody responses in Asutsuare were more significantly associated with age than the responses measured in Obom. Conclusion The pattern of antibody responses measured in people living in the high and low malaria transmission setting was similar. All antibody responses measured against the asexual antigen MSP3 increased, however, IgG and IgG1 responses against gametocyte antigen Pfs230 decreased in moving from the dry to the peak season in both sites. Whilst asexual and gametocyte prevalence was similar between the seasons in the low transmission setting, in the high transmission setting asexual parasite prevalence increased but gametocyte prevalence decreased in the rainy season relative to the dry season.
Collapse
Affiliation(s)
- Festus K Acquah
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana.,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Aminata C Lo
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana.,Parasitology Department, University Cheikh Anta Diop, Dakar, Senegal
| | - Kwadwo Akyea-Mensah
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana
| | - Hamza B Abagna
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana
| | - Babacar Faye
- Parasitology Department, University Cheikh Anta Diop, Dakar, Senegal
| | - Michael Theisen
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark.,Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Ben A Gyan
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana
| | - Linda E Amoah
- Immunology Department, Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Accra, Ghana. .,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
| |
Collapse
|
26
|
Cutts JC, Agius PA, Zaw Lin, Powell R, Moore K, Draper B, Simpson JA, Fowkes FJI. Pregnancy-specific malarial immunity and risk of malaria in pregnancy and adverse birth outcomes: a systematic review. BMC Med 2020; 18:14. [PMID: 31941488 PMCID: PMC6964062 DOI: 10.1186/s12916-019-1467-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 11/11/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND In endemic areas, pregnant women are highly susceptible to Plasmodium falciparum malaria characterized by the accumulation of parasitized red blood cells (pRBC) in the placenta. In subsequent pregnancies, women develop protective immunity to pregnancy-associated malaria and this has been hypothesized to be due to the acquisition of antibodies to the parasite variant surface antigen VAR2CSA. In this systematic review we provide the first synthesis of the association between antibodies to pregnancy-specific P. falciparum antigens and pregnancy and birth outcomes. METHODS We conducted a systematic review and meta-analysis of population-based studies (published up to 07 June 2019) of pregnant women living in P. falciparum endemic areas that examined antibody responses to pregnancy-specific P. falciparum antigens and outcomes including placental malaria, low birthweight, preterm birth, peripheral parasitaemia, maternal anaemia, and severe malaria. RESULTS We searched 6 databases and identified 33 studies (30 from Africa) that met predetermined inclusion and quality criteria: 16 studies contributed estimates in a format enabling inclusion in meta-analysis and 17 were included in narrative form only. Estimates were mostly from cross-sectional data (10 studies) and were heterogeneous in terms of magnitude and direction of effect. Included studies varied in terms of antigens tested, methodology used to measure antibody responses, and epidemiological setting. Antibody responses to pregnancy-specific pRBC and VAR2CSA antigens, measured at delivery, were associated with placental malaria (9 studies) and may therefore represent markers of infection, rather than correlates of protection. Antibody responses to pregnancy-specific pRBC, but not recombinant VAR2CSA antigens, were associated with trends towards protection from low birthweight (5 studies). CONCLUSIONS Whilst antibody responses to several antigens were positively associated with the presence of placental and peripheral infections, this review did not identify evidence that any specific antibody response is associated with protection from pregnancy-associated malaria across multiple populations. Further prospective cohort studies using standardized laboratory methods to examine responses to a broad range of antigens in different epidemiological settings and throughout the gestational period, will be necessary to identify and prioritize pregnancy-specific P. falciparum antigens to advance the development of vaccines and serosurveillance tools targeting pregnant women.
Collapse
Affiliation(s)
- Julia C Cutts
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.
| | - Paul A Agius
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia
| | - Zaw Lin
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Rosanna Powell
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia
| | - Kerryn Moore
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Bridget Draper
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Freya J I Fowkes
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia. .,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia. .,Department of Infectious Diseases, Monash University, Melbourne, Australia.
| |
Collapse
|
27
|
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.
Collapse
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
| |
Collapse
|
28
|
Zakama AK, Gaw SL. Malaria in Pregnancy: What the Obstetric Provider in Nonendemic Areas Needs to Know. Obstet Gynecol Surv 2019; 74:546-556. [PMID: 31830300 PMCID: PMC7560991 DOI: 10.1097/ogx.0000000000000704] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
IMPORTANCE Globally, more than 125 million women each year are at risk of malaria during pregnancy. Endemic regions carry the greatest burden; however, with globalization, providers in nonendemic regions are encountering increasing numbers of women exposed to or infected with malaria. OBJECTIVES The aim of this article is to provide obstetric providers in nonendemic areas with updated information on malaria infection in pregnancy focusing on pregnancy management and malaria prevention and treatment. EVIDENCE ACQUISITION This article is based on review of the most recent peer-reviewed articles and guidelines from the Centers for Disease Control and Prevention and the World Health Organization. FINDINGS Malaria infection in pregnancy causes maternal anemia, low birth weight, preterm birth, stillbirth, and miscarriages through placental malaria and severe infections. Pregnant women traveling to malaria-endemic areas should be advised against travel. If travel must occur, they should be provided with region-specific chemoprophylaxis and given methods for preventing infection. In the event that a pregnant patient has an acute malarial infection, prompt evaluation is needed to determine whether there are severe features. Medications for uncomplicated or severe malaria infection should be started as soon as the diagnosis is made. CONCLUSIONS AND RELEVANCE Malaria in pregnancy causes significant perinatal complications. Obstetric providers should be aware of the impact and how to prevent and treat malaria infection during pregnancy. Malaria infection should be suspected in women with concerning symptoms and recent travel to endemic areas. Providers should know the management of uncomplicated and severe malarial infection in pregnancy.
Collapse
Affiliation(s)
- Arthurine K. Zakama
- Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, San Francisco, California, USA
| | - Stephanie L. Gaw
- Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, San Francisco, California, USA
| |
Collapse
|
29
|
Julien JP, Wardemann H. Antibodies against Plasmodium falciparum malaria at the molecular level. Nat Rev Immunol 2019; 19:761-775. [DOI: 10.1038/s41577-019-0209-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2019] [Indexed: 12/11/2022]
|
30
|
Abstract
One hundred twenty-five million pregnant women are at risk for contracting malaria, a preventable cause of maternal and infant morbidity and death. Malaria parasites contribute to adverse pregnancy and birth outcomes due to their preferential accumulation in placental intervillous spaces. Pregnant women are particularly vulnerable to malaria infections, and malaria infections during pregnancy put their fetuses at risk. Malaria in pregnancy is associated with anemia, stillbirth, low birth weight and maternal and fetal death. We review the challenges to diagnosing malaria in pregnancy, as well as strategies to prevent and treat malaria in pregnancy. Finally, we discuss the current gaps in knowledge and potential areas for continued research.
Collapse
Affiliation(s)
- Melissa Bauserman
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, United States.
| | - Andrea L Conroy
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Krysten North
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Jackie Patterson
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Carl Bose
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Steve Meshnick
- Department of Epidemiology, University of North Carolina Gilligns School of Global Public Health, Chapel Hill, NC
| |
Collapse
|
31
|
Functional Antibodies against Placental Malaria Parasites Are Variant Dependent and Differ by Geographic Region. Infect Immun 2019; 87:IAI.00865-18. [PMID: 30988054 DOI: 10.1128/iai.00865-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/05/2019] [Indexed: 02/06/2023] Open
Abstract
During pregnancy, Plasmodium falciparum-infected erythrocytes (IE) accumulate in the intervillous spaces of the placenta by binding to chondroitin sulfate A (CSA) and elicit inflammatory responses that are associated with poor pregnancy outcomes. Primigravidae lack immunity to IE that sequester in the placenta and thus are susceptible to placental malaria (PM). Women become resistant to PM over successive pregnancies as antibodies to placental IE are acquired. Here, we assayed plasma collected at delivery from Malian and Tanzanian women of different parities for total antibody levels against recombinant VAR2CSA antigens (FCR3 allele), and for surface reactivity and binding inhibition and opsonizing functional activities against IE using two CSA-binding laboratory isolates (FCR3 and NF54). Overall, antibody reactivity to VAR2CSA recombinant proteins and to CSA-binding IE was higher in multigravidae than in primigravidae. However, plasma from Malian gravid women reacted more strongly with FCR3 whereas Tanzanian plasma preferentially reacted with NF54. Further, acquisition of functional antibodies was variant dependent: binding inhibition of P. falciparum strain NF54 (P < 0.001) but not of the strain FCR3 increased significantly with parity, while only opsonizing activity against FCR3 (P < 0.001) increased significantly with parity. In addition, opsonizing and binding inhibition activities of plasma of multigravidae were significantly correlated in assays of FCR3 (r = 0.4, P = 0.01) but not of NF54 isolates; functional activities did not correlate in plasma from primigravidae. These data suggest that IE surface-expressed epitopes involved in each functional activity differ among P. falciparum strains. Consequently, geographic bias in circulating strains may impact antibody functions. Our study has implications for the development of PM vaccines aiming to achieve broad protection against various parasite strains.
Collapse
|
32
|
Intermittent screening and treatment with dihydroartemisinin-piperaquine and intermittent preventive therapy with sulfadoxine-pyrimethamine have similar effects on malaria antibody in pregnant Malawian women. Sci Rep 2019; 9:7878. [PMID: 31133672 PMCID: PMC6536723 DOI: 10.1038/s41598-019-44340-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 05/15/2019] [Indexed: 11/08/2022] Open
Abstract
In a randomised trial comparing intermittent screening and treatment (IST) with dihydroartemisinin-piperaquine (DP) and intermittent preventive therapy against malaria in pregnancy (IPT) with sulfadoxine-pyrimethamine (SP) in Malawi, the impacts of IST-DP and IPT-SP on the development and maintenance of malaria antibody immunity were compared. Pregnant Malawian women were randomised to receive IST-DP or IPT-SP. In a nested study, paired enrolment and delivery plasma samples from 681 women were assayed for antibodies against recombinant antigens and for IgG and opsonising antibodies to antigens found on infected erythrocytes (IEs). At delivery, antibody responses did not differ between study arms. Between enrolment and delivery, antibodies to recombinant antigens decreased, whereas antibodies to IEs including opsonising antibodies remained stable. Overall, changes in antibody responses over pregnancy did not differ by treatment arm. Stratifying by gravidity, antibody to schizont extract decreased more in multigravidae receiving IST-DP than IPT-SP. There was minimal impact of treatment arm on the development and maintenance of malaria immunity. While antibodies to recombinant antigens declined between enrolment and delivery, antibodies directed against IEs tended to be more stable, suggesting longer-lasting protection.Clinical trial registration: Pa n African Clinical Trials Registry (PACTR201103000280319) 14/03/2011. URL: http://www.isrctn.com/ISRCTN69800930 .
Collapse
|
33
|
Mace KE, Arguin PM, Lucchi NW, Tan KR. Malaria Surveillance - United States, 2016. MMWR. SURVEILLANCE SUMMARIES : MORBIDITY AND MORTALITY WEEKLY REPORT. SURVEILLANCE SUMMARIES 2019; 68:1-35. [PMID: 31099769 DOI: 10.15585/mmwr.ss6805a1] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PROBLEM/CONDITION Malaria in humans is caused by intraerythrocytic protozoa of the genus Plasmodium. These parasites are transmitted by the bite of an infective female Anopheles species mosquito. The majority of malaria infections in the United States occur among persons who have traveled to regions with ongoing malaria transmission. However, malaria is occasionally acquired by persons who have not traveled out of the country through exposure to infected blood products, congenital transmission, laboratory exposure, or local mosquitoborne transmission. Malaria surveillance in the United States is conducted to provide information on its occurrence (e.g., temporal, geographic, and demographic), guide prevention and treatment recommendations for travelers and patients, and facilitate transmission control measures if locally acquired cases are identified. PERIOD COVERED This report summarizes confirmed malaria cases in persons with onset of illness in 2016 and summarizes trends in previous years. DESCRIPTION OF SYSTEM Malaria cases diagnosed by blood film microscopy, polymerase chain reaction, or rapid diagnostic tests are reported to local and state health departments by health care providers or laboratory staff members. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), the National Notifiable Diseases Surveillance System (NNDSS), or direct CDC consultations. CDC reference laboratories provide diagnostic assistance and conduct antimalarial drug resistance marker testing on blood samples submitted by health care providers or local or state health departments. This report summarizes data from the integration of all NMSS and NNDSS cases, CDC reference laboratory reports, and CDC clinical consultations. RESULTS CDC received reports of 2,078 confirmed malaria cases with onset of symptoms in 2016, including two congenital cases, three cryptic cases, and one case acquired through blood transfusion. The number of malaria cases diagnosed in the United States has been increasing since the mid-1970s. However, in 2015 a decrease occurred in the number of cases, specifically from the region of West Africa, likely due to altered travel related to the Ebola virus disease outbreak. The number of confirmed malaria cases in 2016 represents a 36% increase compared with 2015, and the 2016 total is 153 more cases than in 2011, which previously had the highest number of cases (1,925 cases). In 2016, a total of 1,729 cases originated from Africa, and 1,061 (61.4%) of these came from West Africa. P. falciparum accounted for the majority of the infections (1,419 [68.2%]), followed by P. vivax (251 [12.1%]). Fewer than 2% of patients were infected by two species (23 [1.1%]). The infecting species was not reported or was undetermined in 10.8% of cases. CDC provided diagnostic assistance for 12.1% of confirmed cases and tested 10.8% of specimens with P. falciparum infections for antimalarial resistance markers. Of the U.S. resident patients who reported reason for travel, 69.4% were travelers who were visiting friends and relatives. The proportion of U.S. residents with malaria who reported taking any chemoprophylaxis in 2016 (26.3%) was similar to that in 2015 (26.6%), and adherence was poor among those who took chemoprophylaxis. Among the 964 U.S. residents with malaria for whom information on chemoprophylaxis use and travel region were known, 94.0% of patients with malaria did not adhere to or did not take a CDC-recommended chemoprophylaxis regimen. Among 795 women with malaria, 50 were pregnant, and one had adhered to mefloquine chemoprophylaxis. Forty-one (2.0%) malaria cases occurred among U.S. military personnel in 2016, a comparable proportion to that in 2015 (23 cases [1.5%]). Among all reported cases in 2016, a total of 306 (14.7%) were classified as severe illnesses, and seven persons died. In 2016, CDC analyzed 144 P. falciparum-positive and nine P. falciparum mixed species samples for surveillance of antimalarial resistance markers (although certain loci were untestable in some samples); genetic polymorphisms associated with resistance to pyrimethamine were identified in 142 (97.9%), to sulfadoxine in 98 (70.5%), to chloroquine in 67 (44.7%), to mefloquine in six (4.3%), and to atovaquone in one (<1.0%). The completeness of key variables (e.g., species, country of acquisition, and resident status) was 79.4% in 2016 and 75.7% in 2015. INTERPRETATION The number of reported malaria cases in 2016 continued a decades-long increasing trend and is the highest since 1972. The importation of malaria reflects the overall increase in global travel trends to and from areas where malaria is endemic; a transient decrease in the acquisition of cases, predominantly from West Africa, occurred in 2015. In 2016, more cases (absolute number) originated from regions of the world with widespread malaria transmission. Since the early 2000s, worldwide interventions to reduce malaria have been successful; however, progress has plateaued in recent years, the disease remains endemic in many regions, and the use of appropriate prevention measures by travelers remains inadequate. PUBLIC HEALTH ACTIONS The best way to prevent malaria is to take chemoprophylaxis medication during travel to a country where malaria is endemic. Malaria infections can be fatal if not diagnosed and treated promptly with antimalarial medications appropriate for the patient's age and medical history, the likely country of malaria acquisition, and previous use of antimalarial chemoprophylaxis. In 2018, two tafenoquine-based antimalarials were approved by the Food and Drug Administration (FDA) for use in the United States. Arakoda was approved for use by adults for chemoprophylaxis and is available as a weekly dosage that is convenient during travel, which might improve adherence and also can prevent relapses from P. vivax and P. ovale infections. Krintafel was approved for radical cure of P. vivax infections in those >16 years old. In April 2019, intravenous artesunate became the first-line medication for treatment of severe malaria in the United States. Because intravenous artesunate is not FDA approved, it is available from CDC under an investigational new drug protocol. Detailed recommendations for preventing malaria are available to the general public at the CDC website (https://www.cdc.gov/malaria/travelers/drugs.html). Health care providers should consult the CDC Guidelines for Treatment of Malaria in the United States and contact the CDC's Malaria Hotline for case management advice when needed. Malaria treatment recommendations are available online (https://www.cdc.gov/malaria/diagnosis_treatment) and from the Malaria Hotline (770-488-7788 or toll-free at 855-856-4713). Persons submitting malaria case reports (care providers, laboratories, and state and local public health officials) should provide complete information because incomplete reporting compromises case investigations and efforts to prevent infections and examine trends in malaria cases. Adherence to recommended malaria prevention strategies is low among U.S. travelers; reasons for nonadherence include prematurely stopping after leaving the area where malaria was endemic, forgetting to take the medication, and experiencing a side effect. Molecular surveillance of antimalarial drug resistance markers (https://www.cdc.gov/malaria/features/ars.html) enables CDC to track, guide treatment, and manage drug resistance in malaria parasites both domestically and internationally. More samples are needed to improve the completeness of antimalarial drug resistance analysis; therefore, CDC requests that blood specimens be submitted for all cases of malaria diagnosed in the United States.
Collapse
Affiliation(s)
- Kimberly E Mace
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, CDC
| | - Paul M Arguin
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, CDC
| | - Naomi W Lucchi
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, CDC
| | - Kathrine R Tan
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, CDC
| |
Collapse
|
34
|
Attaher O, Mahamar A, Swihart B, Barry A, Diarra BS, Kanoute MB, Dembele AB, Keita S, Gaoussou S, Issiaka D, Dicko A, Duffy PE, Fried M. Age-dependent increase in antibodies that inhibit Plasmodium falciparum adhesion to a subset of endothelial receptors. Malar J 2019; 18:128. [PMID: 30971252 PMCID: PMC6458601 DOI: 10.1186/s12936-019-2764-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/03/2019] [Indexed: 11/30/2022] Open
Abstract
Background Plasmodium falciparum-infected erythrocytes (IE) sequester in deep vascular beds where their adhesion is mediated by an array of endothelial surface receptors. Because parasite adhesion has been associated with disease, antibodies that block this activity may confer protective immunity. Here, levels of plasma anti-adhesion activity and surface reactivity against freshly collected IEs from malaria-infected children were measured in a Malian birth cohort and related to child age and malaria infection history. Methods Plasma samples from children enrolled at birth in a longitudinal cohort study of mother–infant pairs in Ouelessebougou, Mali were collected at multiple time points during follow-up visits. Anti-adhesion antibodies (i.e., inhibit IE binding to any of several endothelial receptors) and reactivity with surface IE proteins were measured using a binding inhibition assay and by flow cytometry, respectively. Results Levels of antibodies that inhibit the binding of children’s IE to the receptors ICAM-1, integrin α3β1 and laminin increased with age. The breadth of antibodies that inhibit ICAM-1 and laminin adhesion (defined as the proportion of IE isolates whose binding was reduced by ≥ 50%) also significantly increased with age. The number of malaria infections prior to plasma collection was associated with levels of plasma reactivity to IE surface proteins, but not levels of anti-adhesion activity. Conclusions Age is associated with increased levels of antibodies that reduce adhesion of children’s IE to three of the ten endothelial receptors evaluated here. These results suggest that anti-adhesion antibodies to some but not all endothelial receptors are acquired during the first few years of life. Electronic supplementary material The online version of this article (10.1186/s12936-019-2764-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, USA
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Bacary S Diarra
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Moussa B Kanoute
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Adama B Dembele
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Sekouba Keita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Santara Gaoussou
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, USA.
| |
Collapse
|
35
|
Janitzek CM, Peabody J, Thrane S, H R Carlsen P, G Theander T, Salanti A, Chackerian B, A Nielsen M, Sander AF. A proof-of-concept study for the design of a VLP-based combinatorial HPV and placental malaria vaccine. Sci Rep 2019; 9:5260. [PMID: 30918267 PMCID: PMC6437161 DOI: 10.1038/s41598-019-41522-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 03/08/2019] [Indexed: 11/16/2022] Open
Abstract
In Africa, cervical cancer and placental malaria (PM) are a major public health concern. There is currently no available PM vaccine and the marketed Human Papillomavirus (HPV) vaccines are prohibitively expensive. The idea of a combinatorial HPV and PM vaccine is attractive because the target population for vaccination against both diseases, adolescent girls, would be overlapping in Sub-Saharan Africa. Here we demonstrate proof-of-concept for a combinatorial vaccine utilizing the AP205 capsid-based virus-like particle (VLP) designed to simultaneously display two clinically relevant antigens (the HPV RG1 epitope and the VAR2CSA PM antigen). Three distinct combinatorial VLPs were produced displaying one, two or five concatenated RG1 epitopes without obstructing the VLP’s capacity to form. Co-display of VAR2CSA was achieved through a split-protein Tag/Catcher interaction without hampering the vaccine stability. Vaccination with the combinatorial vaccine(s) was able to reduce HPV infection in vivo and induce anti-VAR2CSA IgG antibodies, which inhibited binding between native VAR2CSA expressed on infected red blood cells and chondroitin sulfate A in an in vitro binding-inhibition assay. These results show that the Tag/Catcher AP205 VLP system can be exploited to make a combinatorial vaccine capable of eliciting antibodies with dual specificity.
Collapse
Affiliation(s)
- Christoph M Janitzek
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Julianne Peabody
- Department of Molecular Genetics & Microbiology, University of New Mexico School of Medicine, Albuquerque, USA
| | - Susan Thrane
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Philip H R Carlsen
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Thor G Theander
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Ali Salanti
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Bryce Chackerian
- Department of Molecular Genetics & Microbiology, University of New Mexico School of Medicine, Albuquerque, USA
| | - Morten A Nielsen
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Adam F Sander
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark. .,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark.
| |
Collapse
|
36
|
Seitz J, Morales-Prieto DM, Favaro RR, Schneider H, Markert UR. Molecular Principles of Intrauterine Growth Restriction in Plasmodium Falciparum Infection. Front Endocrinol (Lausanne) 2019; 10:98. [PMID: 30930847 PMCID: PMC6405475 DOI: 10.3389/fendo.2019.00098] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 02/01/2019] [Indexed: 12/21/2022] Open
Abstract
Malaria in pregnancy still constitutes a particular medical challenge in tropical and subtropical regions. Of the five Plasmodium species that are pathogenic to humans, infection with Plasmodium falciparum leads to fulminant progression of the disease with massive impact on pregnancy. Severe anemia of the mother, miscarriage, stillbirth, preterm delivery and intrauterine growth restriction (IUGR) with reduced birth weight are frequent complications that lead to more than 10,000 maternal and 200,000 perinatal deaths annually in sub-Saharan Africa alone. P. falciparum can adhere to the placenta via the expression of the surface antigen VAR2CSA, which leads to sequestration of infected erythrocytes in the intervillous space. This process induces a placental inflammation with involvement of immune cells and humoral factors. Especially, monocytes get activated and change the release of soluble mediators, including a variety of cytokines. This proinflammatory environment contributes to disorders of angiogenesis, blood flow, autophagy, and nutrient transport in the placenta and erythropoiesis. Collectively, they impair placental functions and, consequently, fetal growth. The discovery that women in endemic regions develop a certain immunity against VAR2CSA-expressing parasites with increasing number of pregnancies has redefined the understanding of malaria in pregnancy and offers strategies for the development of vaccines. The following review gives an overview of molecular processes in P. falciparum infection in pregnancy which may be involved in the development of IUGR.
Collapse
Affiliation(s)
- Johanna Seitz
- Placenta Lab, Department of Obstetrics, Jena University Hospital, Jena, Germany
| | | | - Rodolfo R. Favaro
- Placenta Lab, Department of Obstetrics, Jena University Hospital, Jena, Germany
| | - Henning Schneider
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
- Department of Obstetrics and Gynecology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Udo Rudolf Markert
- Placenta Lab, Department of Obstetrics, Jena University Hospital, Jena, Germany
| |
Collapse
|
37
|
Anabire NG, Aryee PA, Abdul-Karim A, Abdulai IB, Quaye O, Awandare GA, Helegbe GK. Prevalence of malaria and hepatitis B among pregnant women in Northern Ghana: Comparing RDTs with PCR. PLoS One 2019; 14:e0210365. [PMID: 30726218 PMCID: PMC6364880 DOI: 10.1371/journal.pone.0210365] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 12/20/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND High prevalence of malaria and hepatitis B has been reported among pregnant women in Ghana. In endemic areas, the diagnoses of malaria and hepatitis B among pregnant women on antenatal visits are done using histidine-rich protein 2 (HRP2) and hepatitis B surface antigen (HBsAg) rapid diagnostic tests (RDTs), respectively, which are, however, reported to give some false positive results. Also, socio-economic determinants have been drawn from these RDTs results which may have questionable implications. Thus, this study was aimed at evaluating the prevalence of malaria and hepatitis B by comparing RDTs with polymerase chain reaction (PCR) outcomes, and relating the PCR prevalence with socio-economic status among pregnant women in Northern Ghana. METHODS We screened 2071 pregnant women on their first antenatal visit for Plasmodium falciparum and hepatitis B virus (HBV) using HRP2 and HBsAg RDTs, and confirming the infections with PCR. Socio-economic and obstetric information were collected using a pre-tested questionnaire, and associations with the infections were determined using Pearson's chi-square and multinomial logistic regression analyses at a significance level of p<0.05. RESULTS The prevalence of the infections by RDTs/PCR was: 14.1%/13.4% for P. falciparum mono-infection, 7.9%/7.5% for HBV mono-infection, and 1.9%/1.7% for P. falciparum/HBV co-infection. No statistical difference in prevalence rates were observed between the RDTs and PCRs (χ2 = 0.119, p = 0.73 for malaria and χ2 = 0.139, p = 0.709 for hepatitis B). Compared with PCRs, the sensitivity/specificity of the RDTs was 97.5%/99.1% and 97.9%/99.4% for HRP2 and HBsAg respectively. Socio-economic status was observed not to influence HBV mono-infection among the pregnant women (educational status: AOR = 0.78, 95% CI = 0.52-1.16, p = 0.222; economic status: AOR = 1.07, 95% CI = 0.72-1.56, p = 0.739; financial status: AOR = 0.66, 95% CI = 0.44-1.00, p = 0.052). However, pregnant women with formal education were at a lower risk for P. falciparum mono-infection (AOR = 0.48, 95% CI = 0.32-0.71, p<0.001) and P. falciparum/HBV co-infection (AOR = 0.27, 95% CI = 0.11-0.67, p = 0.005). Also those with good financial status were also at a lower risk for P. falciparum mono-infection (AOR = 0.52, 95% CI = 0.36-0.74, p<0.001). CONCLUSION Our data has shown that, the RDTs are comparable to PCR and can give a representative picture of the prevalence of malaria and hepatitis B in endemic countries. Also, our results support the facts that improving socio-economic status is paramount in eliminating malaria in endemic settings. However, socio-economic status did not influence the prevalence of HBV mono-infection among pregnant women in Northern Ghana.
Collapse
Affiliation(s)
- Nsoh Godwin Anabire
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon- Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra-Ghana
- Department of Biochemistry & Molecular Medicine, School of Medicine and Health Sciences, University for Development Studies, Tamale-Ghana
| | - Paul Armah Aryee
- Department of Nutritional Sciences, School of Allied Health Sciences, University for Development Studies, Tamale-Ghana
| | - Abass Abdul-Karim
- Zonal Public Health Laboratory, Tamale Teaching Hospital, Tamale-Ghana
| | | | - Osbourne Quaye
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon- Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra-Ghana
| | - Gordon Akanzuwine Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon- Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra-Ghana
| | - Gideon Kofi Helegbe
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon- Accra, Ghana
- Department of Biochemistry & Molecular Medicine, School of Medicine and Health Sciences, University for Development Studies, Tamale-Ghana
| |
Collapse
|
38
|
Abstract
The blood stage of the malaria parasite life cycle is responsible for all the clinical symptoms of malaria. During the blood stage, Plasmodium merozoites invade and multiply within host red blood cells (RBCs). Here, we review the progress made, challenges faced, and new strategies available for the development of blood stage malaria vaccines. We discuss our current understanding of immune responses against blood stages and the status of clinical development of various blood stage malaria vaccine candidates. We then discuss possible paths forward to develop effective blood stage malaria vaccines. This includes a discussion of protective immune mechanisms that can be elicited to target blood stage parasites, novel delivery systems, immunoassays and animal models to optimize vaccine candidates in preclinical studies, and use of challenge models to get an early readout of vaccine efficacy.
Collapse
|
39
|
Global genetic diversity of var2csa in Plasmodium falciparum with implications for malaria in pregnancy and vaccine development. Sci Rep 2018; 8:15429. [PMID: 30337594 PMCID: PMC6193930 DOI: 10.1038/s41598-018-33767-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/06/2018] [Indexed: 12/24/2022] Open
Abstract
Malaria infection during pregnancy, caused by the sequestering of Plasmodium falciparum parasites in the placenta, leads to high infant mortality and maternal morbidity. The parasite-placenta adherence mechanism is mediated by the VAR2CSA protein, a target for natural occurring immunity. Currently, vaccine development is based on its ID1-DBL2Xb domain however little is known about the global genetic diversity of the encoding var2csa gene, which could influence vaccine efficacy. In a comprehensive analysis of the var2csa gene in >2,000 P. falciparum field isolates across 23 countries, we found that var2csa is duplicated in high prevalence (>25%), African and Oceanian populations harbour a much higher diversity than other regions, and that insertions/deletions are abundant leading to an underestimation of the diversity of the locus. Further, ID1-DBL2Xb haplotypes associated with adverse birth outcomes are present globally, and African-specific haplotypes exist, which should be incorporated into vaccine design.
Collapse
|
40
|
Mayor A, Dobaño C, Nhabomba A, Guinovart C, Jiménez A, Manaca MN, Aguilar R, Barbosa A, Rodríguez MH, Cisteró P, Quimice LM, Menéndez C, Aponte JJ, Ordi J, Chitnis CE, Alonso PL. IgM and IgG against Plasmodium falciparum lysate as surrogates of malaria exposure and protection during pregnancy. Malar J 2018; 17:182. [PMID: 29743114 PMCID: PMC5944166 DOI: 10.1186/s12936-018-2331-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/24/2018] [Indexed: 11/10/2022] Open
Abstract
Background Difficulties to disentangle the protective versus exposure role of anti-malarial antibodies hamper the identification of clinically-relevant immune targets. Here, factors affecting maternal IgG and IgMs against Plasmodium falciparum antigens, as well as their relationship with parasite infection and clinical outcomes, were assessed in mothers and their children. Antibody responses among 207 Mozambican pregnant women at delivery against MSP119, EBA175, AMA1, DBLα and parasite lysate (3D7, R29 and E8B parasite lines), as well as the surface of infected erythrocytes, were assessed by enzyme-linked immunosorbent assay and flow cytometry. The relationship between antibody levels, maternal infection and clinical outcomes was assessed by multivariate regression analysis. Results Placental infection was associated with an increase in maternal levels of IgGs and IgMs against a broad range of parasite antigens. The multivariate analysis including IgGs and IgMs showed that the newborn weight increased with increasing IgG levels against a parasite lysate, whereas the opposite association was found with IgMs. IgGs are markers of protection against poor pregnancy outcomes and IgMs of parasite exposure. Conclusions Adjusting the analysis for the simultaneous effect of IgMs and IgGs can contribute to account for heterogeneous exposure to P. falciparum when assessing immune responses effective against malaria in pregnancy. Electronic supplementary material The online version of this article (10.1186/s12936-018-2331-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Alfredo Mayor
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain. .,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.
| | - Carlota Dobaño
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Augusto Nhabomba
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Caterina Guinovart
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Alfons Jiménez
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | | | - Ruth Aguilar
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Arnoldo Barbosa
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Mauricio H Rodríguez
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Pau Cisteró
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | - Lazaro M Quimice
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Clara Menéndez
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - John J Aponte
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Jaume Ordi
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain
| | - Chetan E Chitnis
- International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Pedro L Alonso
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK Building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| |
Collapse
|
41
|
Hommel M, Chan JA, Umbers AJ, Langer C, Rogerson SJ, Smith JD, Beeson JG. Evaluating antibody functional activity and strain-specificity of vaccine candidates for malaria in pregnancy using in vitro phagocytosis assays. Parasit Vectors 2018; 11:69. [PMID: 29378634 PMCID: PMC5789608 DOI: 10.1186/s13071-018-2653-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 01/16/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria in pregnancy is a major cause of poor maternal and infant health, and is associated with the sequestration of P. falciparum-infected erythrocytes (IE) in the placenta. The leading vaccine candidate for pregnancy malaria, VAR2CSA, has been shown to induce antibodies that inhibit IE adhesion to the placental receptor chondroitin sulfate A (CSA), potentially preventing placental infection. However, the ability of vaccination-induced antibodies to promote opsonic phagocytosis is not well defined, but likely to be an important component of protective immunity. METHODS We investigated the use of an opsonic phagocytosis assay to evaluate antibodies induced by pregnancy malaria vaccine candidate antigens based on VAR2CSA. Opsonic phagocytosis was measured by flow cytometry and visualized by electron microscopy. We measured vaccine-induced antibody reactivity to placental type IEs from different geographical origins, and the functional ability of antibodies raised in immunized rabbits to induce phagocytosis by a human monocyte cell line. RESULTS Immunization-induced antibodies showed a mixture of strain-specific and cross-reactive antibody recognition of different placental-binding parasite lines. Antibodies generated against the DBL5 and DBL3 domains of VAR2CSA effectively promoted the opsonic phagocytosis of IEs by human monocytes; however, these functional antibodies were largely allele-specific and not cross-reactive. This has significant implications for the development of vaccines aiming to achieve a broad coverage against diverse parasite strains. Using competition ELISAs, we found that acquired human antibodies among pregnant women targeted both cross-reactive and allele-specific epitopes, consistent with what we observed with vaccine-induced antibodies. CONCLUSIONS Vaccines based on domains of VAR2CSA induced opsonic phagocytosis of IEs in a strain-specific manner. Assays measuring this phagocytic activity have the potential to aid the development and evaluation of vaccines against malaria in pregnancy.
Collapse
Affiliation(s)
| | | | | | | | - Stephen J Rogerson
- Department of Medicine, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Joseph D Smith
- Center for Infectious Diseases Research, Seattle, WA, USA
| | - James G Beeson
- Burnet Institute, Melbourne, VIC, Australia. .,Department of Medicine, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia. .,Department of Microbiology and Central Clinical School, Monash University, Clayton, VIC, Australia.
| |
Collapse
|
42
|
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.
Collapse
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
| | | | | |
Collapse
|
43
|
Tuju J, Kamuyu G, Murungi LM, Osier FHA. Vaccine candidate discovery for the next generation of malaria vaccines. Immunology 2017; 152:195-206. [PMID: 28646586 PMCID: PMC5588761 DOI: 10.1111/imm.12780] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/12/2017] [Accepted: 06/19/2017] [Indexed: 12/21/2022] Open
Abstract
Although epidemiological observations, IgG passive transfer studies and experimental infections in humans all support the feasibility of developing highly effective malaria vaccines, the precise antigens that induce protective immunity remain uncertain. Here, we review the methodologies applied to vaccine candidate discovery for Plasmodium falciparum malaria from the pre- to post-genomic era. Probing of genomic and cDNA libraries with antibodies of defined specificities or functional activity predominated the former, whereas reverse vaccinology encompassing high throughput in silico analyses of genomic, transcriptomic or proteomic parasite data sets is the mainstay of the latter. Antibody-guided vaccine design spanned both eras but currently benefits from technological advances facilitating high-throughput screening and downstream applications. We make the case that although we have exponentially increased our ability to identify numerous potential vaccine candidates in a relatively short space of time, a significant bottleneck remains in their validation and prioritization for evaluation in clinical trials. Longitudinal cohort studies provide supportive evidence but results are often conflicting between studies. Demonstration of antigen-specific antibody function is valuable but the relative importance of one mechanism over another with regards to protection remains undetermined. Animal models offer useful insights but may not accurately reflect human disease. Challenge studies in humans are preferable but prohibitively expensive. In the absence of reliable correlates of protection, suitable animal models or a better understanding of the mechanisms underlying protective immunity in humans, vaccine candidate discovery per se may not be sufficient to provide the paradigm shift necessary to develop the next generation of highly effective subunit malaria vaccines.
Collapse
Affiliation(s)
- James Tuju
- KEMRI‐Wellcome Trust Research ProgrammeCentre for Geographic Medicine CoastKilifiKenya
- Department of BiochemistryPwani UniversityKilifiKenya
| | - Gathoni Kamuyu
- KEMRI‐Wellcome Trust Research ProgrammeCentre for Geographic Medicine CoastKilifiKenya
| | - Linda M. Murungi
- KEMRI‐Wellcome Trust Research ProgrammeCentre for Geographic Medicine CoastKilifiKenya
| | - Faith H. A. Osier
- KEMRI‐Wellcome Trust Research ProgrammeCentre for Geographic Medicine CoastKilifiKenya
- Centre for Infectious DiseasesHeidelberg University HospitalHeidelbergGermany
- Department of Biomedical SciencesPwani UniversityKilifiKenya
| |
Collapse
|
44
|
Siriwardhana C, Fang R, Salanti A, Leke RGF, Bobbili N, Taylor DW, Chen JJ. Statistical prediction of immunity to placental malaria based on multi-assay antibody data for malarial antigens. Malar J 2017; 16:391. [PMID: 28962616 PMCID: PMC5622501 DOI: 10.1186/s12936-017-2041-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/21/2017] [Indexed: 11/29/2022] Open
Abstract
Background Plasmodium falciparum infections are especially severe in pregnant women because infected erythrocytes (IE) express VAR2CSA, a ligand that binds to placental trophoblasts, causing IE to accumulate in the placenta. Resulting inflammation and pathology increases a woman’s risk of anemia, miscarriage, premature deliveries, and having low birthweight (LBW) babies. Antibodies (Ab) to VAR2CSA reduce placental parasitaemia and improve pregnancy outcomes. Currently, no single assay is able to predict if a woman has adequate immunity to prevent placental malaria (PM). This study measured Ab levels to 28 malarial antigens and used the data to develop statistical models for predicting if a woman has sufficient immunity to prevent PM. Methods Archival plasma samples from 1377 women were screened in a bead-based multiplex assay for Ab to 17 VAR2CSA-associated antigens (full length VAR2CSA (FV2), DBL 1-6 of the FCR3, 3D7 and 7G8 lines, ID1-ID2a (FCR3 and 3D7) and 11 antigens that have been reported to be associated with immunity to P. falciparum (AMA-1, CSP, EBA-175, LSA1, MSP1, MSP2, MSP3, MSP11, Pf41, Pf70 and RESA)). Ab levels along with clinical variables (age, gravidity) were used in the following seven statistical approaches: logistic regression full model, logistic regression reduced model, recursive partitioning, random forests, linear discriminant analysis, quadratic discriminant analysis, and support vector machine. Results The best and simplest model proved to be the logistic regression reduced model. AMA-1, MSP2, EBA-175, Pf41, and MSP11 were found to be the top five most important predictors for the PM status based on overall prediction performance. Conclusions Not surprising, significant differences were observed between PM positive (PM+) and PM negative (PM−) groups for Ab levels to the majority of malaria antigens. Individually though, these malarial antigens did not achieve reasonably high performances in terms of predicting the PM status. Utilizing multiple antigens in predictive models considerably improved discrimination power compared to individual assays. Among seven different classifiers considered, the reduced logistic regression model produces the best overall predictive performance. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-2041-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Chathura Siriwardhana
- Biostatistics Core, Department of Complementary and Integrative Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA
| | - Rui Fang
- Biostatistics Core, Department of Complementary and Integrative Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA
| | - Ali Salanti
- Centre for Medical Parasitology at Department of Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Rose G F Leke
- The Biotechnology Center, Faculty of Medicine and Biomedical Research, University of Yaoundé I, Yaoundé, Cameroon
| | - Naveen Bobbili
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA
| | - Diane Wallace Taylor
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA
| | - John J Chen
- Biostatistics Core, Department of Complementary and Integrative Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA.
| |
Collapse
|
45
|
Sharma L, Shukla G. Placental Malaria: A New Insight into the Pathophysiology. Front Med (Lausanne) 2017; 4:117. [PMID: 28791290 PMCID: PMC5524764 DOI: 10.3389/fmed.2017.00117] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 07/11/2017] [Indexed: 12/30/2022] Open
Abstract
Malaria in pregnancy poses a great health risk to mother and her fetus and results into complications, such as abortion, still birth, intra uterine growth retardation, and low birth weight. The heavy infiltration of Plasmodium falciparum-infected RBCs in the intervillous spaces of placenta seems to be responsible for all the complications observed. Infected RBCs in the placenta cause an inflammatory environment with increase in inflammatory cells and cytokines which is deleterious to the placenta. Increased inflammatory responses in the infected placenta result into oxidative stress that in turn causes oxidative stress-induced placental cell death. Moreover, heat shock proteins that are produced in high concentration in stressed cells to combat the stress have been reported in fewer concentrations in malaria-infected placenta. Pathologies associated with placental malaria seems to be the effect of a change in immune status from antibody-mediated immune response to cell-mediated immune response resulting into excess inflammation, oxidative stress, apoptosis, and decreased heat shock protein expression. However, we also need to study other aspects of pathologies so that better drugs can be designed with new molecular targets.
Collapse
Affiliation(s)
- Lalita Sharma
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Geeta Shukla
- Department of Microbiology, Panjab University, Chandigarh, India
| |
Collapse
|
46
|
Fonseca AM, Quinto L, Jiménez A, González R, Bardají A, Maculuve S, Dobaño C, Rupérez M, Vala A, Aponte JJ, Sevene E, Macete E, Menéndez C, Mayor A. Multiplexing detection of IgG against Plasmodium falciparum pregnancy-specific antigens. PLoS One 2017; 12:e0181150. [PMID: 28715465 PMCID: PMC5513451 DOI: 10.1371/journal.pone.0181150] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/27/2017] [Indexed: 11/18/2022] Open
Abstract
Background Pregnant women exposed to Plasmodium falciparum generate antibodies against VAR2CSA, the parasite protein that mediates adhesion of infected erythrocytes to the placenta. There is a need of high-throughput tools to determine the fine specificity of these antibodies that can be used to identify immune correlates of protection and exposure. Here we aimed at developing a multiplex-immunoassay to detect antibodies against VAR2CSA antigens. Methods and findings We constructed two multiplex-bead arrays, one composed of 3 VAR2CSA recombinant-domains (DBL3X, DBL5Ɛ and DBL6Ɛ) and another composed of 46 new peptides covering VAR2CSA conserved and semi-conserved regions. IgG reactivity was similar in multiplexed and singleplexed determinations (Pearson correlation, protein array: R2 = 0.99 and peptide array: R2 = 0.87). IgG recognition of 25 out of 46 peptides and all recombinant-domains was higher in pregnant Mozambican women (n = 106) than in Mozambican men (n = 102) and Spanish individuals (n = 101; p<0.05). Agreement of IgG levels detected in cryopreserved plasma and in elutions from dried blood spots was good after exclusion of inappropriate filter papers. Under heterogeneous levels of exposure to malaria, similar seropositivity cutoffs were obtained using finite mixture models applied to antibodies measured on pregnant Mozambican women and average of antibodies measured on pregnant Spanish women never exposed to malaria. The application of the multiplex-bead array developed here, allowed the assessment of higher IgG levels and seroprevalences against VAR2CSA-derived antigens in women pregnant during 2003–2005 than during 2010–2012, in accordance with the levels of malaria transmission reported for these years in Mozambique. Conclusions The multiplex bead-based immunoassay to detect antibodies against selected 25 VAR2CSA new-peptides and recombinant-domains was successfully implemented. Analysis of field samples showed that responses were specific among pregnant women and dependent on the level of exposure to malaria. This platform provides a high-throughput approach to investigating correlates of protection and identifying serological markers of exposure for malaria in pregnancy.
Collapse
Affiliation(s)
- Ana Maria Fonseca
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Graduate Program in Areas of Basic and Applied Biology (GABBA), Universidade do Porto, Porto, Portugal
| | - Llorenç Quinto
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Alfons Jiménez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - Raquel González
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Azucena Bardají
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Sonia Maculuve
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Carlota Dobaño
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Maria Rupérez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Anifa Vala
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - John J. Aponte
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Esperanza Sevene
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
- Eduardo Mondlane University, Maputo, Mozambique
| | - Eusebio Macete
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Clara Menéndez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Alfredo Mayor
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
- * E-mail:
| |
Collapse
|
47
|
Gonçalves BP, Walker PG, Cairns M, Tiono AB, Bousema T, Drakeley C. Pregnant Women: An Overlooked Asset to Plasmodium falciparum Malaria Elimination Campaigns? Trends Parasitol 2017; 33:510-518. [DOI: 10.1016/j.pt.2017.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/20/2017] [Accepted: 03/01/2017] [Indexed: 01/28/2023]
|
48
|
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]
|
49
|
Abstract
One hundred and twenty-five million women in malaria-endemic areas become pregnant each year (see Dellicour et al. PLoS Med7: e1000221 [2010]) and require protection from infection to avoid disease and death for themselves and their offspring. Chloroquine prophylaxis was once a safe approach to prevention but has been abandoned because of drug-resistant parasites, and intermittent presumptive treatment with sulfadoxine-pyrimethamine, which is currently used to protect pregnant women throughout Africa, is rapidly losing its benefits for the same reason. No other drugs have yet been shown to be safe, tolerable, and effective as prevention for pregnant women, although monthly dihydroartemisinin-piperaquine has shown promise for reducing poor pregnancy outcomes. Insecticide-treated nets provide some benefits, such as reducing placental malaria and low birth weight. However, this leaves a heavy burden of maternal, fetal, and infant morbidity and mortality that could be avoided. Women naturally acquire resistance to Plasmodium falciparum over successive pregnancies as they acquire antibodies against parasitized red cells that bind chondroitin sulfate A in the placenta, suggesting that a vaccine is feasible. Pregnant women are an important reservoir of parasites in the community, and women of reproductive age must be included in any elimination effort, but several features of malaria during pregnancy will require special consideration during the implementation of elimination programs.
Collapse
Affiliation(s)
- Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD 20892
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD 20892
| |
Collapse
|
50
|
Pehrson C, Salanti A, Theander TG, Nielsen MA. Pre-clinical and clinical development of the first placental malaria vaccine. Expert Rev Vaccines 2017; 16:613-624. [PMID: 28434376 DOI: 10.1080/14760584.2017.1322512] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Malaria during pregnancy is a massive health problem in endemic areas. Placental malaria infections caused by Plasmodium falciparum are responsible for up to one million babies being born with a low birth weight every year. Significant efforts have been invested into preventing the condition. Areas covered: Pub Med was searched using the broad terms 'malaria parasite placenta' to identify studies of interactions between parasite and host, 'prevention of placental malaria' to identify current strategies to prevent placental malaria, and 'placental malaria vaccine' to identify pre-clinical vaccine development. However, all papers from these searches were not systematically included. Expert commentary: The first phase I clinical trials of vaccines are well underway. Trials testing efficacy are more complicated to carry out as only women that are exposed to parasites during pregnancy will contribute to endpoint measurements, further it may require extensive follow-up to establish protection. Future second generation vaccines may overcome the inherent challenges in making an effective placental malaria vaccine.
Collapse
Affiliation(s)
- Caroline Pehrson
- a Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Science , University of Copenhagen , Copenhagen , Denmark.,b Department of Infectious Diseases , Copenhagen University Hospital (Rigshospitalet) , Copenhagen , Denmark
| | - Ali Salanti
- a Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Science , University of Copenhagen , Copenhagen , Denmark.,b Department of Infectious Diseases , Copenhagen University Hospital (Rigshospitalet) , Copenhagen , Denmark
| | - Thor G Theander
- a Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Science , University of Copenhagen , Copenhagen , Denmark.,b Department of Infectious Diseases , Copenhagen University Hospital (Rigshospitalet) , Copenhagen , Denmark
| | - Morten A Nielsen
- a Centre for Medical Parasitology at Department of Immunology and Microbiology, Faculty of Health and Medical Science , University of Copenhagen , Copenhagen , Denmark.,b Department of Infectious Diseases , Copenhagen University Hospital (Rigshospitalet) , Copenhagen , Denmark
| |
Collapse
|