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Rent S, Bauserman M, Laktabai J, Tshefu AK, Taylor SM. Malaria in Pregnancy: Key Points for the Neonatologist. Neoreviews 2023; 24:e539-e552. [PMID: 37653081 DOI: 10.1542/neo.24-9-e539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
In malaria-endemic regions, infection with the malaria parasite Plasmodium during pregnancy has been identified as a key modifiable factor in preterm birth, the delivery of low-birthweight infants, and stillbirth. Compared with their nonpregnant peers, pregnant persons are at higher risk for malaria infection. Malaria infection can occur at any time during pregnancy, with negative effects for the pregnant person and the fetus, depending on the trimester in which the infection is contracted. Pregnant patients who are younger, in their first or second pregnancy, and those coinfected with human immunodeficiency virus are at increased risk for malaria. Common infection prevention measures during pregnancy include the use of insecticide-treated bed nets and the use of intermittent preventive treatment with monthly doses of antimalarials, beginning in the second trimester in pregnant patients in endemic areas. In all trimesters, artemisinin-combination therapies are the first-line treatment for uncomplicated falciparum malaria, similar to treatment in nonpregnant adults. The World Health Organization recently revised its recommendations, now listing the specific medication artemether-lumefantrine as first-line treatment for uncomplicated malaria in the first trimester. While strong prevention and detection methods exist, use of these techniques remains below global targets. Ongoing work on approaches to treatment and prevention of malaria during pregnancy remains at the forefront of global maternal child health research.
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Affiliation(s)
- Sharla Rent
- Department of Pediatrics, Duke University School of Medicine, Durham, NC
| | | | | | - Antoinette K Tshefu
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Steve M Taylor
- Department of Medicine, Duke University School of Medicine, Durham, NC
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2
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Kassa MW, Hasang W, Barateiro A, Damelang T, Brewster J, Dombrowski JG, Longley RJ, Chung AW, Wunderlich G, Mueller I, Aitken EH, Marinho CRF, Rogerson SJ. Acquisition of antibodies to Plasmodium falciparum and Plasmodium vivax antigens in pregnant women living in a low malaria transmission area of Brazil. Malar J 2022; 21:360. [PMID: 36457056 PMCID: PMC9714246 DOI: 10.1186/s12936-022-04402-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/25/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Pregnant women have increased susceptibility to Plasmodium falciparum malaria and acquire protective antibodies over successive pregnancies. Most studies that investigated malaria antibody responses in pregnant women are from high transmission areas in sub-Saharan Africa, while reports from Latin America are scarce and inconsistent. The present study sought to explore the development of antibodies against P. falciparum and Plasmodium vivax antigens in pregnant women living in a low transmission area in the Brazilian Amazon. METHODS In a prospective cohort study, plasma samples from 408 pregnant women (of whom 111 were infected with P. falciparum, 96 had infections with P. falciparum and P. vivax, and 201 had no Plasmodium infection) were used to measure antibody levels. Levels of IgG and opsonizing antibody to pregnancy-specific variant surface antigens (VSAs) on infected erythrocytes (IEs), 10 recombinant VAR2CSA Duffy binding like (DBL domains), 10 non-pregnancy-specific P. falciparum merozoite antigens, and 10 P. vivax antigens were measured by flow cytometry, ELISA, and multiplex assays. Antibody levels and seropositivity among the groups were compared. RESULTS Antibodies to VSAs on P. falciparum IEs were generally low but were higher in currently infected women and women with multiple P. falciparum episodes over pregnancy. Many women (21%-69%) had antibodies against each individual VAR2CSA DBL domain, and antibodies to DBLs correlated with each other (r ≥ 0.55, p < 0.0001), but not with antibody to VSA or history of infection. Infection with either malaria species was associated with higher seropositivity rate for antibodies against P. vivax proteins, adjusted odds ratios (95% CI) ranged from 5.6 (3.2, 9.7), p < 0.0001 for PVDBPII-Sal1 to 15.7 (8.3, 29.7), p < 0.0001 for PvTRAg_2. CONCLUSIONS Pregnant Brazilian women had low levels of antibodies to pregnancy-specific VSAs that increased with exposure. They frequently recognized both VAR2CSA DBL domains and P. vivax antigens, but only the latter varied with infection. Apparent antibody prevalence is highly dependent on the assay platform used.
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Affiliation(s)
- Meseret W. Kassa
- grid.1008.90000 0001 2179 088XDepartment of Medicine, University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Level 5, 792 Elizabeth St, University of Melbourne, Melbourne, VIC 3000 Australia
| | - Wina Hasang
- grid.1008.90000 0001 2179 088XDepartment of Infectious Diseases, University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC Australia
| | - André Barateiro
- grid.11899.380000 0004 1937 0722Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Timon Damelang
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, University of Melbourne, Melbourne, VIC Australia
| | - Jessica Brewster
- grid.1042.70000 0004 0432 4889Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC Australia
| | - Jamille G. Dombrowski
- grid.11899.380000 0004 1937 0722Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rhea J. Longley
- grid.1042.70000 0004 0432 4889Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XDepartment of Medical Biology, University of Melbourne, Melbourne, VIC Australia
| | - Amy W. Chung
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, University of Melbourne, Melbourne, VIC Australia
| | - Gerhard Wunderlich
- grid.11899.380000 0004 1937 0722Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Ivo Mueller
- grid.1042.70000 0004 0432 4889Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XDepartment of Medical Biology, University of Melbourne, Melbourne, VIC Australia
| | - Elizabeth H. Aitken
- grid.1008.90000 0001 2179 088XDepartment of Infectious Diseases, University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, University of Melbourne, Melbourne, VIC Australia
| | - Claudio R. F. Marinho
- grid.11899.380000 0004 1937 0722Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Stephen J. Rogerson
- grid.1008.90000 0001 2179 088XDepartment of Medicine, University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Level 5, 792 Elizabeth St, University of Melbourne, Melbourne, VIC 3000 Australia ,grid.1008.90000 0001 2179 088XDepartment of Infectious Diseases, University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC Australia
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3
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Talundzic E, Scott S, Owino SO, Campo DS, Lucchi NW, Udhayakumar V, Moore JM, Peterson DS. Polymorphic Molecular Signatures in Variable Regions of the Plasmodium falciparum var2csa DBL3x Domain Are Associated with Virulence in Placental Malaria. Pathogens 2022; 11:520. [PMID: 35631041 PMCID: PMC9147263 DOI: 10.3390/pathogens11050520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/15/2022] [Accepted: 04/24/2022] [Indexed: 11/17/2022] Open
Abstract
The Plasmodium falciparum protein VAR2CSA allows infected erythrocytes to accumulate within the placenta, inducing pathology and poor birth outcomes. Multiple exposures to placental malaria (PM) induce partial immunity against VAR2CSA, making it a promising vaccine candidate. However, the extent to which VAR2CSA genetic diversity contributes to immune evasion and virulence remains poorly understood. The deep sequencing of the var2csa DBL3X domain in placental blood from forty-nine primigravid and multigravid women living in malaria-endemic western Kenya revealed numerous unique sequences within individuals in association with chronic PM but not gravidity. Additional analysis unveiled four distinct sequence types that were variably present in mixed proportions amongst the study population. An analysis of the abundance of each of these sequence types revealed that one was inversely related to infant gestational age, another was inversely related to placental parasitemia, and a third was associated with chronic PM. The categorization of women according to the type to which their dominant sequence belonged resulted in the segregation of types as a function of gravidity: two types predominated in multigravidae whereas the other two predominated in primigravidae. The univariate logistic regression analysis of sequence type dominance further revealed that gravidity, maternal age, placental parasitemia, and hemozoin burden (within maternal leukocytes), reported a lack of antimalarial drug use, and infant gestational age and birth weight influenced the odds of membership in one or more of these sequence predominance groups. Cumulatively, these results show that unique var2csa sequences differentially appear in women with different PM exposure histories and segregate to types independently associated with maternal factors, infection parameters, and birth outcomes. The association of some var2csa sequence types with indicators of pathogenesis should motivate vaccine efforts to further identify and target VAR2CSA epitopes associated with maternal morbidity and poor birth outcomes.
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Affiliation(s)
- Eldin Talundzic
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA; (E.T.); (N.W.L.); (V.U.)
| | - Stephen Scott
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, USA;
| | - Simon O. Owino
- Boehringer Ingelheim Animal Health, Athens, GA 30601, USA;
| | - David S. Campo
- Molecular Epidemiology and Bioinformatics Laboratory, Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA;
| | - Naomi W. Lucchi
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA; (E.T.); (N.W.L.); (V.U.)
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA; (E.T.); (N.W.L.); (V.U.)
| | - Julie M. Moore
- Department of Infectious Diseases and Immunology, University of Florida, Gainesville, FL 32611, USA
| | - David S. Peterson
- Department of Infectious Diseases, University of Georgia, Athens, GA 30602, USA;
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
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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.
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Doolan DL. Malaria research in Australia: looking through the lens of the past towards the future. Int J Parasitol 2021; 51:1255-1263. [PMID: 34780720 DOI: 10.1016/j.ijpara.2021.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 10/19/2022]
Abstract
Malaria remains a global health priority, with substantial resources devoted to control and intervention since the causative parasite was first identified in 1880. Major advances have been made in discovery and translational research activities aimed at prevention, treatment and control. Laboratory-based, clinical, and field-based studies have complemented public health approaches. Australian scientists have played important roles, developing and applying innovative approaches, novel research tools and cutting-edge technologies in animal and human models of disease, as well as in disease-endemic settings. This article will provide an insight into 50 years of Australian efforts to discover mechanisms and targets of immunity and pathogenesis; develop new diagnostics, drugs, vaccines, and therapeutics; and assess new public health interventions and control measures in malaria-endemic settings.
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Affiliation(s)
- Denise L Doolan
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health & Medicine, James Cook University, Cairns QLD 4878, Australia.
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6
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Naturally Acquired Antibodies against Plasmodium falciparum: Friend or Foe? Pathogens 2021; 10:pathogens10070832. [PMID: 34357982 PMCID: PMC8308493 DOI: 10.3390/pathogens10070832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 11/17/2022] Open
Abstract
Antibodies are central to acquired immunity against malaria. Plasmodium falciparum elicits antibody responses against many of its protein components, but there is also formation of antibodies against different parts of the red blood cells, in which the parasites spend most of their time. In the absence of a decisive intervention such as a vaccine, people living in malaria endemic regions largely depend on naturally acquired antibodies for protection. However, these antibodies do not confer sterile immunity and the mechanisms of action are still unclear. Most studies have focused on the inhibitory effect of antibodies, but here, we review both the beneficial as well as the potentially harmful roles of naturally acquired antibodies, as well as autoantibodies formed in malaria. We discuss different studies that have sought to understand acquired antibody responses against P. falciparum antigens, and potential problems when different antibodies are combined, such as in naturally acquired immunity.
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7
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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).
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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
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8
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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.
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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
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9
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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.
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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)
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10
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Damelang T, Aitken EH, Hasang W, Lopez E, Killian M, Unger HW, Salanti A, Shub A, McCarthy E, Kedzierska K, Lappas M, Kent SJ, Rogerson SJ, Chung AW. Antibody mediated activation of natural killer cells in malaria exposed pregnant women. Sci Rep 2021; 11:4130. [PMID: 33602987 PMCID: PMC7893158 DOI: 10.1038/s41598-021-83093-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/25/2021] [Indexed: 12/21/2022] Open
Abstract
Immune effector responses against Plasmodium falciparum include antibody-mediated activation of innate immune cells, which can induce Fc effector functions, including antibody-dependent cellular cytotoxicity, and the secretion of cytokines and chemokines. These effector functions are regulated by the composition of immunoglobulin G (IgG) Fc N-linked glycans. However, a role for antibody-mediated natural killer (NK) cells activation or Fc N-linked glycans in pregnant women with malaria has not yet been established. Herein, we studied the capacity of IgG antibodies from pregnant women, with placental malaria or non-placental malaria, to induce NK cell activation in response to placental malaria-associated antigens DBL2 and DBL3. Antibody-mediated NK cell activation was observed in pregnant women with malaria, but no differences were associated with susceptibility to placental malaria. Elevated anti-inflammatory glycosylation patterns of IgG antibodies were observed in pregnant women with or without malaria infection, which were not seen in healthy non-pregnant controls. This suggests that pregnancy-associated anti-inflammatory Fc N-linked glycans may dampen the antibody-mediated activation of NK cells in pregnant women with malaria infection. Overall, although anti-inflammatory glycans and antibody-dependent NK cell activation were detected in pregnant women with malaria, a definitive role for these antibody features in protecting against placental malaria remains to be proven.
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Affiliation(s)
- Timon Damelang
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Elizabeth H Aitken
- Department of Medicine, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Wina Hasang
- Department of Medicine, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Ester Lopez
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Martin Killian
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
- Department of Internal Medicine, Centre Hospitalier Universitaire de Saint-Etienne, Saint-Etienne, France
- Groupe sur l'Immunité des Muqueuses et Agents Pathogènes, Université Jean Monnet Saint-Etienne, Saint-Etienne, France
| | - Holger W Unger
- Liverpool School of Tropical Medicine, Liverpool, UK
- Department of Obstetrics and Gynaecology, Royal Darwin Hospital, Darwin, NT, Australia
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Ali Salanti
- Department for Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Disease, Copenhagen University Hospital, Copenhagen, Denmark
| | - Alexis Shub
- Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, VIC, Australia
| | - Elizabeth McCarthy
- Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, VIC, Australia
| | - Katherine Kedzierska
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Martha Lappas
- Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, VIC, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
- Infectious Diseases Department, Alfred Health, Melbourne Sexual Health Centre, Monash University, Melbourne, VIC, Australia
| | - Stephen J Rogerson
- Department of Medicine, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Amy W Chung
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia.
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11
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Natama HM, Rovira-Vallbona E, Krit M, Guetens P, Sorgho H, Somé MA, Traoré-Coulibaly M, Valéa I, Mens PF, Schallig HDFH, Berkvens D, Kestens L, Tinto H, Rosanas-Urgell A. Genetic variation in the immune system and malaria susceptibility in infants: a nested case-control study in Nanoro, Burkina Faso. Malar J 2021; 20:94. [PMID: 33593344 PMCID: PMC7885350 DOI: 10.1186/s12936-021-03628-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Genetic polymorphisms in the human immune system modulate susceptibility to malaria. However, there is a paucity of data on the contribution of immunogenetic variants to malaria susceptibility in infants, who present differential biological features related to the immaturity of their adaptive immune system, the protective effect of maternal antibodies and fetal haemoglobin. This study investigated the association between genetic variation in innate immune response genes and malaria susceptibility during the first year of life in 656 infants from a birth cohort survey performed in Nanoro, Burkina Faso. METHODS Seventeen single nucleotide polymorphisms (SNPs) in 11 genes of the immune system previously associated with different malaria phenotypes were genotyped using TaqMan allelic hybridization assays in a Fluidigm platform. Plasmodium falciparum infection and clinical disease were documented by active and passive case detection. Case-control association analyses for both alleles and genotypes were carried out using univariate and multivariate logistic regression. For cytokines showing significant SNP associations in multivariate analyses, cord blood supernatant concentrations were measured by quantitative suspension array technology (Luminex). RESULTS Genetic variants in IL-1β (rs1143634) and FcγRIIA/CD32 (rs1801274)-both in allelic, dominant and co-dominant models-were significantly associated with protection from both P. falciparum infection and clinical malaria. Furthermore, heterozygote individuals with rs1801274 SNP in FcγRIIA/CD32 showed higher IL-1RA levels compared to wild-type homozygotes (P = 0.024), a cytokine whose production is promoted by the binding of IgG immune complexes to Fcγ receptors on effector immune cells. CONCLUSIONS These findings indicate that genetic polymorphisms in genes driving innate immune responses are associated to malaria susceptibility during the first year of life, possibly by modulating production of inflammatory mediators.
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Affiliation(s)
- Hamatandi Magloire Natama
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso.
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.
| | | | - Meryam Krit
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Pieter Guetens
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Hermann Sorgho
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso
| | - M Athanase Somé
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso
| | - Maminata Traoré-Coulibaly
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso
| | - Innocent Valéa
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso
| | - Petra F Mens
- Department of Medical Microbiology-Parasitology Unit, Academic Medical Centre, Amsterdam University Medical Centres, Amsterdam, The Netherlands
| | - Henk D F H Schallig
- Department of Medical Microbiology-Parasitology Unit, Academic Medical Centre, Amsterdam University Medical Centres, Amsterdam, The Netherlands
| | - Dirk Berkvens
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Luc Kestens
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Halidou Tinto
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de La Santé, Nanoro, Burkina Faso
- Centre Muraz, Bobo Dioulasso, Burkina Faso
| | - Anna Rosanas-Urgell
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
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12
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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.
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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
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13
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Quanquin NM, Barres LG, Aliyari SR, Day NT, Gerami H, Fisher SJ, Kakuru A, Kamya MR, Havlir DV, Feeney M, Dorsey G, Cheng G, Gaw SL. Gravidity-dependent associations between interferon response and birth weight in placental malaria. Malar J 2020; 19:280. [PMID: 32758231 PMCID: PMC7409479 DOI: 10.1186/s12936-020-03351-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/27/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Maternal malarial infection leads to poor perinatal outcomes, including low birth weight from preterm delivery and/or fetal growth restriction, particularly in primigravidas. In placental malaria, Plasmodium falciparum-infected red blood cells cause an inflammatory response that can interfere with maternal-fetal exchange, leading to poor growth. The type I interferon (IFN-I) pathway plays an immunomodulatory role in viral and bacterial infections, usually by suppressing inflammatory responses. However, its role in placental malaria is unknown. This study examines the cytokine responses in placental tissue from subsets of malaria-infected and uninfected women, and attempts to correlate them with particular birth outcomes. METHODS 40 whole placental biopsy samples were obtained from pregnant women at least 16 years of age recruited to a larger prospective chemoprevention trial against malaria. These were patients at Tororo District Hospital in Uganda, an area of high malaria endemicity where approximately 40% of women have evidence of malaria infection at delivery. They were regularly followed at a local clinic and monitored for fever, with blood smears performed then and at time of delivery to diagnose malaria infection. Placenta biopsies were taken for histological diagnosis of placental malaria, as well as quantitative PCR analysis of genes in the IFN-I pathway (IFN-β, IL-10 and MX-1). Parameters such as infant birth weight and gestational age were also recorded. RESULTS Histological analysis revealed placental malaria in 18 samples, while 22 were found to be uninfected. RT-PCR analysis showed a four-fold increase in IFN-β and IL-10 expression in multigravidas with placental malaria when compared to gravidity-matched, uninfected controls. This effect was not observed in primigravidas. Interestingly, linear regression analysis showed a positive association between IFN-β levels and higher birth weights (β = 101.2 g per log2-fold increase in IFN-β expression, p = 0.042). This association was strongest in primigravidas with placental malaria (β = 339.0, p = 0.006). CONCLUSIONS These results demonstrate differential regulation of the IFN-I pathway in placental malaria according to gravidity, with the greatest anti-inflammatory response seen in multigravidas. The association between IFN-β levels and higher birth weight also suggests a protective role for IFN-I against fetal growth restriction in placental malaria.
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Affiliation(s)
- Natalie M Quanquin
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Lauren G Barres
- Department of Obstetrics & Gynecology, David Geffen School of Medicine At UCLA, Los Angeles, CA, 90095, USA
| | - Saba R Aliyari
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Nathan T Day
- Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology & Reproductive Sciences, University of California San Francisco, 513 Parnassus Ave. HSE16, Box 0556, San Francisco, CA, 94143, USA
| | - Hoda Gerami
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Susan J Fisher
- Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology & Reproductive Sciences, University of California San Francisco, 513 Parnassus Ave. HSE16, Box 0556, San Francisco, CA, 94143, USA
| | - Abel Kakuru
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Diane V Havlir
- Division of Infectious Diseases, Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Margaret Feeney
- Division of Pediatric Infectious Diseases, Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - Grant Dorsey
- Division of Infectious Diseases, Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Genhong Cheng
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Stephanie L Gaw
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA. .,Department of Obstetrics & Gynecology, David Geffen School of Medicine At UCLA, Los Angeles, CA, 90095, USA. .,Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology & Reproductive Sciences, University of California San Francisco, 513 Parnassus Ave. HSE16, Box 0556, San Francisco, CA, 94143, USA.
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14
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Fonseca AM, González R, Bardají A, Jairoce C, Rupérez M, Jiménez A, Quintó L, Cisteró P, Vala A, Sacoor C, Gupta H, Hegewisch-Taylor J, Brew J, Ndam NT, Kariuki S, López M, Dobaño C, Chitnis CE, Ouma P, Ramharter M, Abdulla S, Aponte JJ, Massougbodji A, Briand V, Mombo-Ngoma G, Desai M, Cot M, Nhacolo A, Sevene E, Macete E, Menéndez C, Mayor A. VAR2CSA Serology to Detect Plasmodium falciparum Transmission Patterns in Pregnancy. Emerg Infect Dis 2020; 25:1851-1860. [PMID: 31538557 PMCID: PMC6759269 DOI: 10.3201/eid2510.181177] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Pregnant women constitute a promising sentinel group for continuous monitoring of malaria transmission. To identify antibody signatures of recent Plasmodium falciparum exposure during pregnancy, we dissected IgG responses against VAR2CSA, the parasite antigen that mediates placental sequestration. We used a multiplex peptide-based suspension array in 2,354 samples from pregnant women from Mozambique, Benin, Kenya, Gabon, Tanzania, and Spain. Two VAR2CSA peptides of limited polymorphism were immunogenic and targeted by IgG responses readily boosted during infection and with estimated half-lives of <2 years. Seroprevalence against these peptides reflected declines and rebounds of transmission in southern Mozambique during 2004–2012, reduced exposure associated with use of preventive measures during pregnancy, and local clusters of transmission that were missed by detection of P. falciparum infections. These data suggest that VAR2CSA serology can provide a useful adjunct for the fine-scale estimation of the malaria burden among pregnant women over time and space.
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MESH Headings
- Adult
- Antibodies, Protozoan/immunology
- Antigens, Protozoan/blood
- Antigens, Protozoan/immunology
- Benin/epidemiology
- Female
- Gabon/epidemiology
- Humans
- Immunoglobulin G/immunology
- Kenya/epidemiology
- Malaria, Falciparum/complications
- Malaria, Falciparum/diagnosis
- Malaria, Falciparum/epidemiology
- Malaria, Falciparum/transmission
- Mozambique/epidemiology
- Plasmodium falciparum/immunology
- Pregnancy
- Pregnancy Complications, Parasitic/blood
- Pregnancy Complications, Parasitic/diagnosis
- Pregnancy Complications, Parasitic/epidemiology
- Serologic Tests/methods
- Spain/epidemiology
- Tanzania/epidemiology
- Young Adult
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15
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Mlugu EM, Minzi O, Asghar M, Färnert A, Kamuhabwa AA, Aklillu E. Effectiveness of Sulfadoxine-Pyrimethamine for Intermittent Preventive Treatment of Malaria and Adverse Birth Outcomes in Pregnant Women. Pathogens 2020; 9:pathogens9030207. [PMID: 32168945 PMCID: PMC7157612 DOI: 10.3390/pathogens9030207] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/28/2022] Open
Abstract
Effectiveness of intermittent preventive treatment in pregnancy with sulfadoxine–pyrimethamine (IPTp-SP) for prevention of malaria and adverse birth outcomes can be compromised by parasites-resistance to sulfadoxine–pyrimethamine. This study prospectively evaluated the effectiveness of IPTp-SP in Southeast Tanzania. From January 2017 to May 2019, HIV-negative and malaria-negative (mRDT) pregnant women attending their first antenatal-care visit in the second or third trimester (n = 500) were enrolled to receive monthly IPTp-SP and followed the protocol till delivery. The primary outcome was the prevalence of histopathological placental malaria. Secondary outcomes were anemia, malaria parasites detected during pregnancy and at delivery, adverse birth outcomes (low-birth-weight [LBW], premature birth, fetal anemia, still birth, and spontaneous abortion). Rates of histopathological placental malaria, any parasitemia at delivery (placental, cord or maternal), and any adverse birth outcome were 9.4%, 20.9%, and 26.5%, respectively. Rates of symptomatic malaria and parasitemia during pregnancy were 2.8% and 16%, respectively. Histopathological placental malaria significantly increased the odds of any adverse birth outcomes, particularly LBW. IPTp-SP with more than or equal to three doses significantly improved birth weight and reduced the risk of LBW by 56% compared to <3 SP doses (p = 0.009). IPTp-SP with more than or equal to three doses is still effective in improving birth weight. However, the detection of histopathological placental-malaria in one-tenth and parasitemia in one-fifth of pregnant women reflects the need to optimize the prevention of malaria during pregnancy.
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Affiliation(s)
- Eulambius M. Mlugu
- Department of Pharmaceutics, School of Pharmacy, Muhimbili University of Health and Allied Sciences, Dar es Salaam 0702172, Tanzania;
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital, 141 86 Stockholm, Sweden
| | - Omary Minzi
- Department of Clinical Pharmacy and Pharmacology, School of Pharmacy, Muhimbili University of Health and Allied Sciences, Dar es Salaam 0702172, Tanzania; (O.M.)
| | - Muhammad Asghar
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, 171 76 Stockholm, Sweden; (M.A.); (A.F.)
- Department of Infectious Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden
| | - Anna Färnert
- Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, 171 76 Stockholm, Sweden; (M.A.); (A.F.)
- Department of Infectious Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden
| | - Appolinary A.R. Kamuhabwa
- Department of Clinical Pharmacy and Pharmacology, School of Pharmacy, Muhimbili University of Health and Allied Sciences, Dar es Salaam 0702172, Tanzania; (O.M.)
| | - Eleni Aklillu
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital, 141 86 Stockholm, Sweden
- Correspondence:
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16
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Imported Malaria in Countries where Malaria Is Not Endemic: a Comparison of Semi-immune and Nonimmune Travelers. Clin Microbiol Rev 2020; 33:33/2/e00104-19. [PMID: 32161068 DOI: 10.1128/cmr.00104-19] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The continuous increase in long-distance travel and recent large migratory movements have changed the epidemiological characteristics of imported malaria in countries where malaria is not endemic (here termed non-malaria-endemic countries). While malaria was primarily imported to nonendemic countries by returning travelers, the proportion of immigrants from malaria-endemic regions and travelers visiting friends and relatives (VFRs) in malaria-endemic countries has continued to increase. VFRs and immigrants from malaria-endemic countries now make up the majority of malaria patients in many nonendemic countries. Importantly, this group is characterized by various degrees of semi-immunity to malaria, resulting from repeated exposure to infection and a gradual decline of protection as a result of prolonged residence in non-malaria-endemic regions. Most studies indicate an effect of naturally acquired immunity in VFRs, leading to differences in the parasitological features, clinical manifestation, and odds for severe malaria and clinical complications between immune VFRs and nonimmune returning travelers. There are no valid data indicating evidence for differing algorithms for chemoprophylaxis or antimalarial treatment in semi-immune versus nonimmune malaria patients. So far, no robust biomarkers exist that properly reflect anti-parasite or clinical immunity. Until they are found, researchers should rigorously stratify their study results using surrogate markers, such as duration of time spent outside a malaria-endemic country.
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17
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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.
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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.
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18
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Immunobiological aspects of vaccines in pregnancy: Maternal perspective. MATERNAL IMMUNIZATION 2020. [PMCID: PMC7149477 DOI: 10.1016/b978-0-12-814582-1.00003-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Immunization during pregnancy is an efficient strategy to protect both the mother and the newborn infant against infectious pathogens. Pregnant women have an increased susceptibility to severe infections caused by some pathogens, but the mechanisms involved remain poorly understood. Pregnancy is associated with dynamic changes in maternal immune system that are critical for tolerance of the fetus. These changes could also play an important role in shaping maternal immune components that are transferred to the newborn infant following natural infection or vaccination to prevent infectious diseases in early life. As the momentum for maternal immunization is growing, there is a need to increase our understanding of the immunobiology of maternal immunization in order to better prevent infectious diseases in the pregnant women and the young infant.
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Brabin B, Tinto H, Roberts SA. Testing an infection model to explain excess risk of preterm birth with long-term iron supplementation in a malaria endemic area. Malar J 2019; 18:374. [PMID: 31771607 PMCID: PMC6880560 DOI: 10.1186/s12936-019-3013-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/16/2019] [Indexed: 12/15/2022] Open
Abstract
Background In view of recent evidence from a randomized trial in Burkina Faso that periconceptional iron supplementation substantially increases risk of spontaneous preterm birth (< 37 weeks) in first pregnancies (adjusted relative risk = 2.22; 95% CI 1.39–3.61), explanation is required to understand potential mechanisms, including progesterone mediated responses, linking long-term iron supplementation, malaria and gestational age. Methods The analysis developed a model based on a dual hit inflammatory mechanism arising from simultaneous malaria and gut infections, supported in part by published trial results. This model is developed to understand mechanisms linking iron supplementation, malaria and gestational age. Background literature substantiates synergistic inflammatory effects of these infections where trial data is unavailable. A path modelling exercise assessed direct and indirect paths influencing preterm birth and gestation length. Results A dual hit hypothesis incorporates two main pathways for pro-inflammatory mechanisms, which in this model, interact to increase hepcidin expression. Trial data showed preterm birth was positively associated with C-reactive protein (P = 0.0038) an inflammatory biomarker. The malaria pathway upregulates C-reactive protein and serum hepcidin, thereby reducing iron absorption. The enteric pathway results from unabsorbed gut iron, which induces microbiome changes and pathogenic gut infections, initiating pro-inflammatory events with lipopolysaccharide expression. Data from the trial suggest that raised hepcidin concentration is a mediating catalyst, being inversely associated with shorter gestational age at delivery (P = 0.002) and positively with preterm incidence (P = 0.007). A segmented regression model identified a change-point consisting of two segments before and after a sharp rise in hepcidin concentration. This showed a post change hepcidin elevation in women with increasing C-reactive protein values in late gestation (post-change slope 0.55. 95% CI 0.39–0.92, P < 0.001). Path modelling confirmed seasonal malaria effects on preterm birth, with mediation through C-reactive protein and (non-linear) hepcidin induction. Conclusions Following long-term iron supplementation, dual inflammatory pathways that mediate hepcidin expression and culminate in progesterone withdrawal may account for the reduction in gestational age observed in first pregnancies in this area of high malaria exposure. If correct, this model strongly suggests that in such areas, effective infection control is required prior to iron supplementation to avoid increasing preterm births. Trial registration NCT01210040. Registered with Clinicaltrials.gov on 27th September 2010
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Affiliation(s)
- Bernard Brabin
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, L35QA, UK. .,Institute of Infection and Global Health, University of Liverpool, Liverpool, UK. .,Global Child Health Group, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
| | - Halidou Tinto
- Clinical Research Unit of Nanoro (URCN/IRSS), Nanoro, Burkina Faso
| | - Stephen A Roberts
- Centre for Biostatistics, Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre (MAHSC), Manchester, UK
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Gnidehou S, Mitran CJ, Arango E, Banman S, Mena A, Medawar E, Lima BAS, Doritchamou J, Rajwani J, Jin A, Gavina K, Ntumngia F, Duffy P, Narum D, Ndam NT, Nielsen MA, Salanti A, Kano FS, Carvalho LH, Adams JH, Maestre A, Good MF, Yanow SK. Cross-Species Immune Recognition Between Plasmodium vivax Duffy Binding Protein Antibodies and the Plasmodium falciparum Surface Antigen VAR2CSA. J Infect Dis 2019; 219:110-120. [PMID: 30534974 DOI: 10.1093/infdis/jiy467] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 07/24/2018] [Indexed: 01/23/2023] Open
Abstract
Background In pregnancy, Plasmodium falciparum parasites express the surface antigen VAR2CSA, which mediates adherence of red blood cells to chondroitin sulfate A (CSA) in the placenta. VAR2CSA antibodies are generally acquired during infection in pregnancy and are associated with protection from placental malaria. We observed previously that men and children in Colombia also had antibodies to VAR2CSA, but the origin of these antibodies was unknown. Here, we tested whether infection with Plasmodium vivax is an alternative mechanism of acquisition of VAR2CSA antibodies. Methods We analyzed sera from nonpregnant Colombians and Brazilians exposed to P. vivax and monoclonal antibodies raised against P. vivax Duffy binding protein (PvDBP). Cross-reactivity to VAR2CSA was characterized by enzyme-linked immunosorbent assay, immunofluorescence assay, and flow cytometry, and antibodies were tested for inhibition of parasite binding to CSA. Results Over 50% of individuals had antibodies that recognized VAR2CSA. Affinity-purified PvDBP human antibodies and a PvDBP monoclonal antibody recognized VAR2CSA, showing that PvDBP can give rise to cross-reactive antibodies. Importantly, the monoclonal antibody inhibited parasite binding to CSA, which is the primary in vitro correlate of protection from placental malaria. Conclusions These data suggest that PvDBP induces antibodies that functionally recognize VAR2CSA, revealing a novel mechanism of cross-species immune recognition to falciparum malaria.
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Affiliation(s)
- Sédami Gnidehou
- Department of Biology, Campus Saint-Jean, University of Alberta, Edmonton, Canada
| | | | - Eliana Arango
- Grupo Salud y Comunidad, Facultad de Medicina, Medellín, Colombia
| | - Shanna Banman
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Angie Mena
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Evelyn Medawar
- School of Public Health, University of Alberta, Edmonton, Canada
| | | | - Justin Doritchamou
- National Institute of Allergy and Infectious Diseases, Rockville, Maryland
| | - Jahanara Rajwani
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Albert Jin
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Kenneth Gavina
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases, Rockville, Maryland
| | - David Narum
- National Institute of Allergy and Infectious Diseases, Rockville, Maryland
| | | | - Morten A Nielsen
- Department of Immunology and Microbiology, Center for Medical Parasitology, University of Copenhagen, Denmark
| | - Ali Salanti
- Department of Immunology and Microbiology, Center for Medical Parasitology, University of Copenhagen, Denmark
| | | | | | | | - Amanda Maestre
- Grupo Salud y Comunidad, Facultad de Medicina, Medellín, Colombia
| | - Michael F Good
- Institute for Glycomics, Griffith University, Gold Coast, Australia
| | - Stephanie K Yanow
- School of Public Health, University of Alberta, Edmonton, Canada.,Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
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Antibodies to Cryptic Epitopes in Distant Homologues Underpin a Mechanism of Heterologous Immunity between Plasmodium vivax PvDBP and Plasmodium falciparum VAR2CSA. mBio 2019; 10:mBio.02343-19. [PMID: 31594821 PMCID: PMC6786876 DOI: 10.1128/mbio.02343-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
In this work, we describe a molecular mechanism of heterologous immunity between two distant species of Plasmodium. Our results suggest a mechanism that subverts the classic parasite strategy of presenting highly polymorphic epitopes in surface antigens to evade immunity to that parasite. This alternative immune pathway can be exploited to protect pregnant women from falciparum placental malaria by designing vaccines to cryptic epitopes that elicit broadly inhibitory antibodies against variant parasite strains. Many pathogens evolve extensive genetic variation in virulence proteins as a strategy to evade host immunity. This poses a significant challenge for the host to develop broadly neutralizing antibodies. In Plasmodium falciparum, we show that a mechanism to circumvent this challenge is to elicit antibodies to cryptic epitopes that are not under immune pressure. We previously discovered that antibodies to the Plasmodium vivax invasion protein, PvDBP, cross-react with P. falciparum VAR2CSA, a distantly related virulence factor that mediates placental malaria. Here, we describe the molecular mechanism underlying this cross-species immunity. We identified an epitope in subdomain 1 (SD1) within the Duffy binding-like (DBL) domain of PvDBP that gives rise to cross-reactive antibodies to VAR2CSA and show that human antibodies affinity purified against a synthetic SD1 peptide block parasite adhesion to chondroitin sulfate A (CSA) in vitro. The epitope in SD1 is subdominant and highly conserved in PvDBP, and in turn, SD1 antibodies target cryptic epitopes in P. falciparum VAR2CSA. The epitopes in VAR2CSA recognized by vivax-derived SD1 antibodies (of human and mouse origin) are distinct from those recognized by VAR2CSA immune serum. We mapped two peptides in the DBL5ε domain of VAR2CSA that are recognized by SD1 antibodies. Both peptides map to regions outside the immunodominant sites, and antibodies to these peptides are not elicited following immunization with VAR2CSA or natural infection with P. falciparum in pregnancy, consistent with the cryptic nature of these target epitopes.
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22
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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.
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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
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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] [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.
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Malarial anemia among pregnant women in the south-western coastal city of Mangaluru in India. INFORMATICS IN MEDICINE UNLOCKED 2019. [DOI: 10.1016/j.imu.2019.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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González R, Pons‐Duran C, Piqueras M, Aponte JJ, ter Kuile FO, Menéndez C. Mefloquine for preventing malaria in pregnant women. Cochrane Database Syst Rev 2018; 11:CD011444. [PMID: 30480761 PMCID: PMC6517148 DOI: 10.1002/14651858.cd011444.pub3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for malaria for all women who live in moderate to high malaria transmission areas in Africa. However, parasite resistance to sulfadoxine-pyrimethamine has been increasing steadily in some areas of the region. Moreover, HIV-infected women on cotrimoxazole prophylaxis cannot receive sulfadoxine-pyrimethamine because of potential drug interactions. Thus, there is an urgent need to identify alternative drugs for prevention of malaria in pregnancy. One such candidate is mefloquine. OBJECTIVES To assess the effects of mefloquine for preventing malaria in pregnant women, specifically, to evaluate:• the efficacy, safety, and tolerability of mefloquine for preventing malaria in pregnant women; and• the impact of HIV status, gravidity, and use of insecticide-treated nets on the effects of mefloquine. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), the Malaria in Pregnancy Library, and two trial registers up to 31 January 2018. In addition, we checked references and contacted study authors to identify additional studies, unpublished data, confidential reports, and raw data from published trials. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing mefloquine IPT or mefloquine prophylaxis against placebo, no treatment, or an alternative drug regimen. DATA COLLECTION AND ANALYSIS Two review authors independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when required. Dichotomous outcomes were compared using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes using mean differences (MDs). We have presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach for the following main outcomes of analysis: maternal peripheral parasitaemia at delivery, clinical malaria episodes during pregnancy, placental malaria, maternal anaemia at delivery, low birth weight, spontaneous abortions and stillbirths, dizziness, and vomiting. MAIN RESULTS Six trials conducted between 1987 and 2013 from Thailand (1), Benin (3), Gabon (1), Tanzania (1), Mozambique (2), and Kenya (1) that included 8192 pregnant women met our inclusion criteria.Two trials (with 6350 HIV-uninfected pregnant women) compared two IPTp doses of mefloquine with two IPTp doses of sulfadoxine-pyrimethamine. Two other trials involving 1363 HIV-infected women compared three IPTp doses of mefloquine plus cotrimoxazole with cotrimoxazole. One trial in 140 HIV-infected women compared three doses of IPTp-mefloquine with cotrimoxazole. Finally, one trial enrolling 339 of unknown HIV status compared mefloquine prophylaxis with placebo.Study participants included women of all gravidities and of all ages (four trials) or > 18 years (two trials). Gestational age at recruitment was > 20 weeks (one trial), between 16 and 28 weeks (three trials), or ≤ 28 weeks (two trials). Two of the six trials blinded participants and personnel, and only one had low risk of detection bias for safety outcomes.When compared with sulfadoxine-pyrimethamine, IPTp-mefloquine results in a 35% reduction in maternal peripheral parasitaemia at delivery (RR 0.65, 95% CI 0.48 to 0.86; 5455 participants, 2 studies; high-certainty evidence) but may have little or no effect on placental malaria infections (RR 1.04, 95% CI 0.58 to 1.86; 4668 participants, 2 studies; low-certainty evidence). Mefloquine results in little or no difference in the incidence of clinical malaria episodes during pregnancy (incidence rate ratio (IRR) 0.83, 95% CI 0.65 to 1.05, 2 studies; high-certainty evidence). Mefloquine decreased maternal anaemia at delivery (RR 0.84, 95% CI 0.76 to 0.94; 5469 participants, 2 studies; moderate-certainty evidence). Data show little or no difference in the proportions of low birth weight infants (RR 0.95, 95% CI 0.78 to 1.17; 5641 participants, 2 studies; high-certainty evidence) and in stillbirth and spontaneous abortion rates (RR 1.20, 95% CI 0.91 to 1.58; 6219 participants, 2 studies; I2 statistic = 0%; moderate-certainty evidence). IPTp-mefloquine increased drug-related vomiting (RR 4.76, 95% CI 4.13 to 5.49; 6272 participants, 2 studies; high-certainty evidence) and dizziness (RR 4.21, 95% CI 3.36 to 5.27; participants = 6272, 2 studies; moderate-certainty evidence).When compared with cotrimoxazole, IPTp-mefloquine plus cotrimoxazole probably results in a 48% reduction in maternal peripheral parasitaemia at delivery (RR 0.52, 95% CI 0.30 to 0.93; 989 participants, 2 studies; moderate-certainty evidence) and a 72% reduction in placental malaria (RR 0.28, 95% CI 0.14 to 0.57; 977 participants, 2 studies; moderate-certainty evidence) but has little or no effect on the incidence of clinical malaria episodes during pregnancy (IRR 0.76, 95% CI 0.33 to 1.76, 1 study; high-certainty evidence) and probably no effect on maternal anaemia at delivery (RR 0.94, 95% CI 0.73 to 1.20; 1197 participants, 2 studies; moderate-certainty evidence), low birth weight rates (RR 1.20, 95% CI 0.89 to 1.60; 1220 participants, 2 studies; moderate-certainty evidence), and rates of spontaneous abortion and stillbirth (RR 1.12, 95% CI 0.42 to 2.98; 1347 participants, 2 studies; very low-certainty evidence). Mefloquine was associated with higher risks of drug-related vomiting (RR 7.95, 95% CI 4.79 to 13.18; 1055 participants, one study; high-certainty evidence) and dizziness (RR 3.94, 95% CI 2.85 to 5.46; 1055 participants, 1 study; high-certainty evidence). AUTHORS' CONCLUSIONS Mefloquine was more efficacious than sulfadoxine-pyrimethamine in HIV-uninfected women or daily cotrimoxazole prophylaxis in HIV-infected pregnant women for prevention of malaria infection and was associated with lower risk of maternal anaemia, no adverse effects on pregnancy outcomes (such as stillbirths and abortions), and no effects on low birth weight and prematurity. However, the high proportion of mefloquine-related adverse events constitutes an important barrier to its effectiveness for malaria preventive treatment in pregnant women.
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Affiliation(s)
- Raquel González
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Clara Pons‐Duran
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Mireia Piqueras
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - John J Aponte
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Feiko O ter Kuile
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolMerseysideUKL3 5QA
| | - Clara Menéndez
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
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Martínez-Pérez G, Lansana DP, Omeonga S, Gupta H, Breeze-Barry B, González R, Bardají A, Sarukhan A, Goteh JDK, Tody E, Cisteró P, Benda B, Kercula JD, Kibungu FD, Meyer García-Sípido A, Bassat Q, Tarr-Attia CK, Mayor A. Prevalence of Plasmodium falciparum infection among pregnant women at first antenatal visit in post-Ebola Monrovia, Liberia. Malar J 2018; 17:357. [PMID: 30314489 PMCID: PMC6186138 DOI: 10.1186/s12936-018-2506-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 10/06/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Disruption of malaria control strategies during the West African 2014-2016 Ebola epidemic led to an increase in malaria-attributable mortality. However, recent data on malaria infection in vulnerable groups, such as pregnant women, are lacking in this post-Ebola scenario. This cross-sectional study aimed to assess the prevalence of Plasmodium falciparum infection and of molecular markers of drug resistance among pregnant women attending antenatal care in Monrovia, capital of Liberia. METHODS From October 2016 to June 2017, all pregnant women attending their first antenatal care visit at the Saint Joseph's Catholic Hospital, Monrovia, were invited to participate in the study. In addition to their routine antenatal care tests, capillary blood spotted onto filter papers were collected from all consenting participants to determine presence of P. falciparum by real-time quantitative PCR. Molecular markers of anti-malarial drug resistance were assessed through Sanger sequencing and quantitative PCR in specimens positive for P. falciparum analysis. RESULTS Of the 195 women participants, 24 (12.3%) were P. falciparum-positive by qPCR. Infected women tended to be more commonly primigravidae and younger than uninfected ones. Parasite densities were higher in primigravidae. Fever was more frequently detected among the infected women. No statistically significant association between P. falciparum infection and haemoglobin levels or insecticide-treated net use was found. While high prevalence of genetic polymorphisms associated with chloroquine and amodiaquine resistance were detected, no molecular markers of artemisinin resistance were observed. CONCLUSION Plasmodium falciparum infections are expected to occur in at least one in every eight women attending first ANC at private clinics in Monrovia and outside the peak of the rainy season. Young primigravidae are at increased risk of P. falciparum infection. Molecular analyses did not provide evidence of resistance to artemisinins among the P. falciparum isolates tested. Further epidemiological studies involving pregnant women are necessary to describe the risk of malaria in this highly susceptible group outside Monrovia, as well as to closely monitor the emergence of resistance to anti-malarials, as recommended by the Liberian National Malaria Control Programme.
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Affiliation(s)
- Guillermo Martínez-Pérez
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain. .,Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia.
| | - Dawoh Peter Lansana
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Senga Omeonga
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Himanshu Gupta
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Bondey Breeze-Barry
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Raquel González
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Azucena Bardají
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Adelaida Sarukhan
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - James D K Goteh
- Liberia Medicines and Health Products Regulatory Authority, Monrovia, Liberia
| | - Edith Tody
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Pau Cisteró
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Benard Benda
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Juwe D Kercula
- Liberia Medicines and Health Products Regulatory Authority, Monrovia, Liberia
| | - Fanta D Kibungu
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | | | - Quique Bassat
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.,ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.,Pediatrics Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu (University of Barcelona), Barcelona, Spain
| | - Christine K Tarr-Attia
- Saint Joseph's Catholic Hospital, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Alfredo Mayor
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
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Abstract
Pregnant women are especially susceptible to malaria infection. Without existing immunity, severe malaria can develop requiring emergency treatment, and pregnancy loss is common. In semi-immune women, consequences of malaria for the mother include anaemia while stillbirth, premature delivery and foetal growth restriction affect the developing foetus. Preventive measures include insecticide-treated nets and (in some African settings) intermittent preventive treatment. Prompt management of maternal infection is key, using parenteral artemisinins for severe malaria, and artemisinin combination treatments (ACTs) in the second and third trimesters of pregnancy. ACTs may soon also be recommended as an alternative to quinine as a treatment in the first trimester of pregnancy. Monitoring the safety of antimalarials and understanding their pharmacokinetics is particularly important in pregnancy with the altered maternal physiology and the risks to the developing foetus. As increasing numbers of countries embrace malaria elimination as a goal, the special needs of the vulnerable group of pregnant women and their infants should not be overlooked.
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Affiliation(s)
- Stephen J Rogerson
- Department of Medicine at the Doherty Institute, The University of Melbourne, Melbourne, Australia
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González R, Pons‐Duran C, Piqueras M, Aponte JJ, ter Kuile FO, Menéndez C. Mefloquine for preventing malaria in pregnant women. Cochrane Database Syst Rev 2018; 3:CD011444. [PMID: 29561063 PMCID: PMC5875065 DOI: 10.1002/14651858.cd011444.pub2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for malaria for all women who live in moderate to high malaria transmission areas in Africa. However, parasite resistance to sulfadoxine-pyrimethamine has been increasing steadily in some areas of the region. Moreover, HIV-infected women on cotrimoxazole prophylaxis cannot receive sulfadoxine-pyrimethamine because of potential drug interactions. Thus, there is an urgent need to identify alternative drugs for prevention of malaria in pregnancy. One such candidate is mefloquine. OBJECTIVES To assess the effects of mefloquine for preventing malaria in pregnant women, specifically, to evaluate:• the efficacy, safety, and tolerability of mefloquine for preventing malaria in pregnant women; and• the impact of HIV status, gravidity, and use of insecticide-treated nets on the effects of mefloquine. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), the Malaria in Pregnancy Library, and two trial registers up to 31 January 2018. In addition, we checked references and contacted study authors to identify additional studies, unpublished data, confidential reports, and raw data from published trials. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing mefloquine IPT or mefloquine prophylaxis against placebo, no treatment, or an alternative drug regimen. DATA COLLECTION AND ANALYSIS Two review authors independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when required. Dichotomous outcomes were compared using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes using mean differences (MDs). We have presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach for the following main outcomes of analysis: maternal peripheral parasitaemia at delivery, clinical malaria episodes during pregnancy, placental malaria, maternal anaemia at delivery, low birth weight, spontaneous abortions and stillbirths, dizziness, and vomiting. MAIN RESULTS Six trials conducted between 1987 and 2013 from Thailand (1), Benin (3), Gabon (1), Tanzania (1), Mozambique (2), and Kenya (1) that included 8192 pregnant women met our inclusion criteria.Two trials (with 6350 HIV-uninfected pregnant women) compared two IPTp doses of mefloquine with two IPTp doses of sulfadoxine-pyrimethamine. Two other trials involving 1363 HIV-infected women compared three IPTp doses of mefloquine plus cotrimoxazole with cotrimoxazole. One trial in 140 HIV-infected women compared three doses of IPTp-mefloquine with cotrimoxazole. Finally, one trial enrolling 339 of unknown HIV status compared mefloquine prophylaxis with placebo.Study participants included women of all gravidities and of all ages (four trials) or > 18 years (two trials). Gestational age at recruitment was > 20 weeks (one trial), between 16 and 28 weeks (three trials), or ≤ 28 weeks (two trials). Two of the six trials blinded participants and personnel, and only one had low risk of detection bias for safety outcomes.When compared with sulfadoxine-pyrimethamine, IPTp-mefloquine results in a 35% reduction in maternal peripheral parasitaemia at delivery (RR 0.65, 95% CI 0.48 to 0.86; 5455 participants, 2 studies; high-certainty evidence) but may have little or no effect on placental malaria infections (RR 1.04, 95% CI 0.58 to 1.86; 4668 participants, 2 studies; low-certainty evidence). Mefloquine results in little or no difference in the incidence of clinical malaria episodes during pregnancy (incidence rate ratio (IRR) 0.83, 95% CI 0.65 to 1.05, 2 studies; high-certainty evidence). Mefloquine decreased maternal anaemia at delivery (RR 0.84, 95% CI 0.76 to 0.94; 5469 participants, 2 studies; moderate-certainty evidence). Data show little or no difference in the proportions of low birth weight infants (RR 0.95, 95% CI 0.78 to 1.17; 5641 participants, 2 studies; high-certainty evidence) and in stillbirth and spontaneous abortion rates (RR 1.20, 95% CI 0.91 to 1.58; 6219 participants, 2 studies; I2 statistic = 0%; high-certainty evidence). IPTp-mefloquine increased drug-related vomiting (RR 4.76, 95% CI 4.13 to 5.49; 6272 participants, 2 studies; high-certainty evidence) and dizziness (RR 4.21, 95% CI 3.36 to 5.27; participants = 6272, 2 studies; high-certainty evidence).When compared with cotrimoxazole, IPTp-mefloquine plus cotrimoxazole probably results in a 48% reduction in maternal peripheral parasitaemia at delivery (RR 0.52, 95% CI 0.30 to 0.93; 989 participants, 2 studies; moderate-certainty evidence) and a 72% reduction in placental malaria (RR 0.28, 95% CI 0.14 to 0.57; 977 participants, 2 studies; high-certainty evidence) but has little or no effect on the incidence of clinical malaria episodes during pregnancy (IRR 0.76, 95% CI 0.33 to 1.76, 1 study; high-certainty evidence) and probably no effect on maternal anaemia at delivery (RR 0.94, 95% CI 0.73 to 1.20; 1197 participants, 2 studies; moderate-certainty evidence), low birth weight rates (RR 1.20, 95% CI 0.89 to 1.60; 1220 participants, 2 studies; moderate-certainty evidence), and rates of spontaneous abortion and stillbirth (RR 1.12, 95% CI 0.42 to 2.98; 1347 participants, 2 studies; very low-certainty evidence). Mefloquine was associated with higher risks of drug-related vomiting (RR 7.95, 95% CI 4.79 to 13.18; 1055 participants, one study; high-certainty evidence) and dizziness (RR 3.94, 95% CI 2.85 to 5.46; 1055 participants, 1 study; high-certainty evidence). AUTHORS' CONCLUSIONS Mefloquine was more efficacious than sulfadoxine-pyrimethamine in HIV-uninfected women or daily cotrimoxazole prophylaxis in HIV-infected pregnant women for prevention of malaria infection and was associated with lower risk of maternal anaemia, no adverse effects on pregnancy outcomes (such as stillbirths and abortions), and no effects on low birth weight and prematurity. However, the high proportion of mefloquine-related adverse events constitutes an important barrier to its effectiveness for malaria preventive treatment in pregnant women.
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Key Words
- female
- humans
- pregnancy
- insecticide‐treated bednets
- abortion, spontaneous
- abortion, spontaneous/chemically induced
- abortion, spontaneous/epidemiology
- africa south of the sahara
- africa south of the sahara/epidemiology
- antimalarials
- antimalarials/adverse effects
- antimalarials/therapeutic use
- dizziness
- dizziness/chemically induced
- dizziness/epidemiology
- drug combinations
- drug therapy, combination
- hiv infections
- hiv infections/complications
- infant, low birth weight
- malaria
- malaria/epidemiology
- malaria/prevention & control
- mefloquine
- mefloquine/adverse effects
- mefloquine/therapeutic use
- parasitemia
- parasitemia/epidemiology
- pregnancy complications, parasitic
- pregnancy complications, parasitic/epidemiology
- pregnancy complications, parasitic/prevention & control
- pyrimethamine
- pyrimethamine/adverse effects
- pyrimethamine/therapeutic use
- randomized controlled trials as topic
- sulfadoxine
- sulfadoxine/adverse effects
- sulfadoxine/therapeutic use
- thailand
- thailand/epidemiology
- trimethoprim, sulfamethoxazole drug combination
- trimethoprim, sulfamethoxazole drug combination/therapeutic use
- vomiting
- vomiting/chemically induced
- vomiting/epidemiology
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Affiliation(s)
- Raquel González
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Clara Pons‐Duran
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Mireia Piqueras
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - John J Aponte
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Feiko O ter Kuile
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolUKL3 5QA
| | - Clara Menéndez
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
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Rogerson SJ, Desai M, Mayor A, Sicuri E, Taylor SM, van Eijk AM. Burden, pathology, and costs of malaria in pregnancy: new developments for an old problem. THE LANCET. INFECTIOUS DISEASES 2018; 18:e107-e118. [PMID: 29396010 DOI: 10.1016/s1473-3099(18)30066-5] [Citation(s) in RCA: 164] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 08/07/2017] [Accepted: 10/09/2017] [Indexed: 12/17/2022]
Abstract
Over the past 10 years, knowledge of the burden, economic costs, and consequences of malaria in pregnancy has improved, and the prevalence of malaria caused by Plasmodium falciparum has declined substantially in some geographical areas. In particular, studies outside of Africa have increased the evidence base of Plasmodium vivax in pregnancy. Rapid diagnostic tests have been poor at detecting malaria in pregnant women, while PCR has shown a high prevalence of low density infection, the clinical importance of which is unknown. Erythrocytes infected with P falciparum that express the surface protein VAR2CSA accumulate in the placenta, and VAR2CSA is an important target of protective immunity. Clinical trials for a VAR2CSA vaccine are ongoing, but sequence variation needs to be carefully studied. Health system and household costs still limit access to prevention and treatment services. Within the context of malaria elimination, pregnant women could be used to monitor malaria transmission. This Series paper summarises recent progress and highlights unresolved issues related to the burden of malaria in pregnancy.
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Affiliation(s)
- Stephen J Rogerson
- Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Victoria, Australia.
| | - Meghna Desai
- Malaria Branch, Division of Parasitic Diseases and Malaria, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Alfredo Mayor
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Elisa Sicuri
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain; Health Economics Group, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College, London, UK
| | - Steve M Taylor
- Division of Infectious Diseases and Duke Global Health Institute, Duke University Medical Center, Durham, NC, USA
| | - Anna M van Eijk
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
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Kapisi J, Kakuru A, Jagannathan P, Muhindo MK, Natureeba P, Awori P, Nakalembe M, Ssekitoleko R, Olwoch P, Ategeka J, Nayebare P, Clark TD, Rizzuto G, Muehlenbachs A, Havlir DV, Kamya MR, Dorsey G, Gaw SL. Relationships between infection with Plasmodium falciparum during pregnancy, measures of placental malaria, and adverse birth outcomes. Malar J 2017; 16:400. [PMID: 28982374 PMCID: PMC5629777 DOI: 10.1186/s12936-017-2040-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 09/21/2017] [Indexed: 11/10/2022] Open
Abstract
Background Malaria in pregnancy has been associated with maternal morbidity, placental malaria, and adverse birth outcomes. However, data are limited on the relationships between longitudinal measures of malaria during pregnancy, measures of placental malaria, and birth outcomes. Methods This is a nested observational study of data from a randomized controlled trial of intermittent preventive therapy during pregnancy among 282 participants with assessment of placental malaria and delivery outcomes. HIV-uninfected pregnant women were enrolled at 12–20 weeks of gestation. Symptomatic malaria during pregnancy was measured using passive surveillance and monthly detection of asymptomatic parasitaemia using loop-mediated isothermal amplification (LAMP). Placental malaria was defined as either the presence of parasites in placental blood by microscopy, detection of parasites in placental blood by LAMP, or histopathologic evidence of parasites or pigment. Adverse birth outcomes assessed included low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA) infants. Results The 282 women were divided into three groups representing increasing malaria burden during pregnancy. Fifty-two (18.4%) had no episodes of symptomatic malaria or asymptomatic parasitaemia during the pregnancy, 157 (55.7%) had low malaria burden (0–1 episodes of symptomatic malaria and < 50% of samples LAMP+), and 73 (25.9%) had high malaria burden during pregnancy (≥ 2 episodes of symptomatic malaria or ≥ 50% of samples LAMP+). Women with high malaria burden had increased risks of placental malaria by blood microscopy and LAMP [aRR 14.2 (1.80–111.6) and 4.06 (1.73–9.51), respectively], compared to the other two groups combined. Compared with women with no malaria exposure during pregnancy, the risk of placental malaria by histopathology was higher among low and high burden groups [aRR = 3.27 (1.32–8.12) and aRR = 7.07 (2.84–17.6), respectively]. Detection of placental parasites by any method was significantly associated with PTB [aRR 5.64 (1.46–21.8)], and with a trend towards increased risk for LBW and SGA irrespective of the level of malaria burden during pregnancy. Conclusion Higher malaria burden during pregnancy was associated with placental malaria and together with the detection of parasites in the placenta were associated with increased risk for adverse birth outcomes. Trial Registration Current Controlled Trials Identifier NCT02163447 Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-2040-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- James Kapisi
- School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda.
| | - Abel Kakuru
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Prasanna Jagannathan
- Division of Infectious Diseases and Geographical Medicine, Stanford University, Stanford, CA, USA
| | - Mary K Muhindo
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Paul Natureeba
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Patricia Awori
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Miriam Nakalembe
- Department of Obstetrics and Gynecology, Makerere University College of Health Sciences, Kampala, Uganda
| | - Richard Ssekitoleko
- School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Peter Olwoch
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - John Ategeka
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Tamara D Clark
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Gabrielle Rizzuto
- Department of Pathology, University of California, San Francisco, CA, USA
| | - Atis Muehlenbachs
- Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Diane V Havlir
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Moses R Kamya
- School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Stephanie L Gaw
- Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, CA, USA
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Sesay SSS, Giorgi E, Diggle PJ, Schellenberg D, Lalloo DG, Terlouw DJ. Surveillance in easy to access population subgroups as a tool for evaluating malaria control progress: A systematic review. PLoS One 2017; 12:e0183330. [PMID: 28813522 PMCID: PMC5558981 DOI: 10.1371/journal.pone.0183330] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 08/02/2017] [Indexed: 11/29/2022] Open
Abstract
Background The need for surveillance systems generating targeted, data-driven, responsive control efforts to accelerate and sustain malaria transmission reduction has been emphasized by programme managers, policy makers and scientists. Surveillance using easy-to-access population subgroups (EAGs) may result in considerable cost saving compared to household surveys as the identification and selection of individuals to be surveyed is simplified, fewer personnel are needed, and logistics are simpler. We reviewed available literature on the validation of estimates of key indicators of malaria control progress derived from EAGs, and describe the options to deal with the context specific bias that may occur. Methods A literature search was conducted of all documents reporting validation of estimates of malaria control indicators from EAG surveys before the 31st of December 2016. Additional records were identified through cross-reference from selected records, other applicable policy documents and grey literature. After removal of duplicates, 13, 180 abstracts were evaluated and 2,653 eligible abstracts were identified mentioning surveillance in EAGs, of which 29 full text articles were selected for detailed review. The nine articles selected for systematic review compared estimates from health facility and school surveys with those of a contemporaneous sample of the same population in the same geographic area. Results Review of the available literature on EAGs suitable for surveillance of malaria control progress revealed that little effort has been made to explore the potential approach and settings for use of EAGs; and that there was wide variation in the precision of estimates of control progress between and within studies, particularly for estimates of control intervention coverage. Only one of the studies evaluated the geospatial representativeness of EAG samples, or carried out geospatial analyses to assess or control for lack of geospatial representativeness. Two studies attempted to measure the degree of bias or improve the precision of estimates by controlling for bias in a multivariate analysis; and this was only successful in one study. The observed variability in accuracy of estimates is likely to be caused by selection and/or information bias due to the inherent nature of EAGs. The reviewed studies provided insight into the design and analytical approaches that could be used to limit bias. Conclusion The utility EAGs for routine surveillance of progress in malaria control at the district or sub-district programmatic level will be driven by several factors including whether serial point estimates to measure transmission reduction or more precise geospatial distribution to track ‘hot-spots’ is required, the acceptable degree of precision, the target population, and the resources available for surveillance. The opportunities offered by novel geostatistical analyses and hybrid sampling frames to overcome bias justify a renewed exploration of use of EAGs for malaria monitoring and evaluation.
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Affiliation(s)
- Sanie S. S. Sesay
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- * E-mail:
| | - Emanuele Giorgi
- Medical School, Lancaster University, Lancaster, United Kingdom
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Peter J. Diggle
- Medical School, Lancaster University, Lancaster, United Kingdom
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | | | - David G. Lalloo
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Dianne J. Terlouw
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Abstract
Malaria is caused in humans by five species of single-celled eukaryotic Plasmodium parasites (mainly Plasmodium falciparum and Plasmodium vivax) that are transmitted by the bite of Anopheles spp. mosquitoes. Malaria remains one of the most serious infectious diseases; it threatens nearly half of the world's population and led to hundreds of thousands of deaths in 2015, predominantly among children in Africa. Malaria is managed through a combination of vector control approaches (such as insecticide spraying and the use of insecticide-treated bed nets) and drugs for both treatment and prevention. The widespread use of artemisinin-based combination therapies has contributed to substantial declines in the number of malaria-related deaths; however, the emergence of drug resistance threatens to reverse this progress. Advances in our understanding of the underlying molecular basis of pathogenesis have fuelled the development of new diagnostics, drugs and insecticides. Several new combination therapies are in clinical development that have efficacy against drug-resistant parasites and the potential to be used in single-dose regimens to improve compliance. This ambitious programme to eliminate malaria also includes new approaches that could yield malaria vaccines or novel vector control strategies. However, despite these achievements, a well-coordinated global effort on multiple fronts is needed if malaria elimination is to be achieved.
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Affiliation(s)
- Margaret A Phillips
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, USA
| | | | | | | | - Wesley C Van Voorhis
- University of Washington, Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-emerging Infectious Diseases, Seattle, Washington, USA
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Abstract
Evidence accumulated through the years clearly indicates that antiparasite immune responses can efficiently control malaria parasite infection at all development stages, and under certain circumstances they can prevent parasite infection. Translating these findings into vaccines or immunotherapeutic interventions has been difficult in part because of the extraordinary biological complexity of this parasite, which has several developmental stages expressing unique sets of stage-specific genes and multiple antigens, most of which are antigenically diverse. Nevertheless, in the last 30 years major advances have resulted in characterization of a number of vaccine candidates, exploration of the repertoire of host immune responses to the various parasite stages, and also identification of significant hurdles that need to be overcome. Most important, these advances strengthened the concept that the induction of host immune responses that target all developmental stages of Plasmodium can efficiently control or abrogate Plasmodium infections and strongly support the notion that an effective vaccine can be developed. This vaccine would be a critical component for programs aimed at controlling or eradicating malaria.
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Affiliation(s)
- Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, Maryland 20852
| | - Fidel Zavala
- Departmentof Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
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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.
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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:
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Ndam NT, Mbuba E, González R, Cisteró P, Kariuki S, Sevene E, Rupérez M, Fonseca AM, Vala A, Maculuve S, Jiménez A, Quintó L, Ouma P, Ramharter M, Aponte JJ, Nhacolo A, Massougbodji A, Briand V, Kremsner PG, Mombo-Ngoma G, Desai M, Macete E, Cot M, Menéndez C, Mayor A. Resisting and tolerating P. falciparum in pregnancy under different malaria transmission intensities. BMC Med 2017; 15:130. [PMID: 28712360 PMCID: PMC5513247 DOI: 10.1186/s12916-017-0893-6] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/15/2017] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Resistance and tolerance to Plasmodium falciparum can determine the progression of malaria disease. However, quantitative evidence of tolerance is still limited. We investigated variations in the adverse impact of P. falciparum infections among African pregnant women under different intensities of malaria transmission. METHODS P. falciparum at delivery was assessed by microscopy, quantitative PCR (qPCR) and placental histology in 946 HIV-uninfected and 768 HIV-infected pregnant women from Benin, Gabon, Kenya and Mozambique. Resistance was defined by the proportion of submicroscopic infections and the levels of anti-parasite antibodies quantified by Luminex, and tolerance by the relationship of pregnancy outcomes with parasite densities at delivery. RESULTS P. falciparum prevalence by qPCR in peripheral and/or placental blood of HIV-uninfected Mozambican, Gabonese and Beninese women at delivery was 6% (21/340), 11% (28/257) and 41% (143/349), respectively. The proportion of peripheral submicroscopic infections was higher in Benin (83%) than in Mozambique (60%) and Gabon (55%; P = 0.033). Past or chronic placental P. falciparum infection was associated with an increased risk of preterm birth in Mozambican newborns (OR = 7.05, 95% CI 1.79 to 27.82). Microscopic infections were associated with reductions in haemoglobin levels at delivery among Mozambican women (-1.17 g/dL, 95% CI -2.09 to -0.24) as well as with larger drops in haemoglobin levels from recruitment to delivery in Mozambican (-1.66 g/dL, 95% CI -2.68 to -0.64) and Gabonese (-0.91 g/dL, 95% CI -1.79 to -0.02) women. Doubling qPCR-peripheral parasite densities in Mozambican women were associated with decreases in haemoglobin levels at delivery (-0.16 g/dL, 95% CI -0.29 to -0.02) and increases in the drop of haemoglobin levels (-0.29 g/dL, 95% CI -0.44 to -0.14). Beninese women had higher anti-parasite IgGs than Mozambican women (P < 0.001). No difference was found in the proportion of submicroscopic infections nor in the adverse impact of P. falciparum infections in HIV-infected women from Kenya (P. falciparum prevalence by qPCR: 9%, 32/351) and Mozambique (4%, 15/417). CONCLUSIONS The lowest levels of resistance and tolerance in pregnant women from areas of low malaria transmission were accompanied by the largest adverse impact of P. falciparum infections. Exposure-dependent mechanisms developed by pregnant women to resist the infection and minimise pathology can reduce malaria-related adverse outcomes. Distinguishing both types of defences is important to understand how reductions in transmission can affect malaria disease. TRIAL REGISTRATION ClinicalTrials.gov NCT00811421 . Registered 18 December 2008.
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Affiliation(s)
- Nicaise Tuikue Ndam
- Institut de Recherche pour le Développement (IRD), Paris, France.,COMUE Sorbonne Paris Cité, Faculté de Pharmacie, Paris, France.,Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Emmanuel Mbuba
- Ifakara Health Institute (IHI), Bagamoyo Research and Training Centre (BRTC), Bagamoyo, Tanzania
| | - 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
| | - Pau Cisteró
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Simon Kariuki
- Kenya Medical Research Institute (KEMRI)/Centre for Global Health Research, Kisumu, Kenya
| | - Esperança Sevene
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique.,Universidade Eduardo Mondlane, Maputo, Mozambique
| | - María 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
| | - 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, Universidade do Porto, Porto, Portugal
| | - Anifa Vala
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Sonia Maculuve
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Alfons Jiménez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Llorenç Quintó
- Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Peter Ouma
- Kenya Medical Research Institute (KEMRI)/Centre for Global Health Research, Kisumu, Kenya
| | - Michael Ramharter
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - 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
| | - Arsenio Nhacolo
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Achille Massougbodji
- Faculté des Sciences de la Santé (FSS), Université d'Aboméy Calavi, Cotonou, Benin
| | - Valerie Briand
- Institut de Recherche pour le Développement (IRD), Paris, France
| | - Peter G Kremsner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Ghyslain Mombo-Ngoma
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné, Gabon
| | - Meghna Desai
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Eusebio Macete
- Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Michel Cot
- Institut de Recherche pour le Développement (IRD), Paris, France
| | - 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.
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36
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Al Hammadi A, Mitchell M, Abraham GM, Wang JP. Recrudescence of Plasmodium falciparum in a Primigravida After Nearly 3 Years of Latency. Am J Trop Med Hyg 2017; 96:642-644. [PMID: 28044045 PMCID: PMC5361538 DOI: 10.4269/ajtmh.16-0803] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 11/21/2016] [Indexed: 01/25/2023] Open
Abstract
We present a case of a primigravid woman who presented with Plasmodium falciparum nearly 3 years after she last visited a malaria-endemic region. We review the literature to identify case reports of recrudescent P. falciparum malaria during pregnancy, including those with prolonged latency. Reports of recrudescence of P. falciparum during pregnancy are limited. Plasmodium falciparum infection can persist for years. Recrudescence can occur with waning of immunity following departure from endemic areas. Pregnancy, particularly the primigravid state, is a risk factor for severe infection.
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Affiliation(s)
- Ahmed Al Hammadi
- University of Massachusetts Medical School, Worcester, Massachusetts
| | - Michael Mitchell
- University of Massachusetts Medical School, Worcester, Massachusetts
| | | | - Jennifer P. Wang
- University of Massachusetts Medical School, Worcester, Massachusetts
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37
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Requena P, Arévalo-Herrera M, Menegon M, Martínez-Espinosa FE, Padilla N, Bôtto-Menezes C, Malheiro A, Hans D, Castellanos ME, Robinson L, Samol P, Kochar S, Kochar SK, Kochar DK, Desai M, Sanz S, Quintó L, Mayor A, Rogerson S, Mueller I, Severini C, Del Portillo HA, Bardají A, Chitnis CC, Menéndez C, Dobaño C. Naturally Acquired Binding-Inhibitory Antibodies to Plasmodium vivax Duffy Binding Protein in Pregnant Women Are Associated with Higher Birth Weight in a Multicenter Study. Front Immunol 2017; 8:163. [PMID: 28261219 PMCID: PMC5313505 DOI: 10.3389/fimmu.2017.00163] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/31/2017] [Indexed: 12/11/2022] Open
Abstract
A vaccine to eliminate malaria would need a multi-stage and multi-species composition to achieve robust protection, but the lack of knowledge about antigen targets and mechanisms of protection precludes the development of fully efficacious malaria vaccines, especially for Plasmodium vivax (Pv). Pregnant women constitute a risk population who would greatly benefit from a vaccine preventing the adverse events of Plasmodium infection during gestation. We hypothesized that functional immune responses against putative targets of naturally acquired immunity to malaria and vaccine candidates will be associated with protection against malaria infection and/or poor outcomes during pregnancy. We measured (i) IgG responses to a large panel of Pv and Plasmodium falciparum (Pf) antigens, (ii) the capacity of anti-Pv ligand Duffy binding protein (PvDBP) antibodies to inhibit binding to Duffy antigen, and (iii) cellular immune responses to two Pv antigens, in a subset of 1,056 pregnant women from Brazil, Colombia, Guatemala, India, and Papua New Guinea (PNG). There were significant intraspecies and interspecies correlations for most antibody responses (e.g., PfMSP119 versus PfAMA1, Spearman’s rho = 0.81). Women from PNG and Colombia had the highest levels of IgG overall. Submicroscopic infections seemed sufficient to boost antibody responses in Guatemala but not antigen-specific cellular responses in PNG. Brazil had the highest percentage of Duffy binding inhibition (p-values versus Colombia: 0.040; Guatemala: 0.047; India: 0.003, and PNG: 0.153) despite having low anti-PvDBP IgG levels. Almost all antibodies had a positive association with present infection, and coinfection with the other species increased this association. Anti-PvDBP, anti-PfMSP1, and anti-PfAMA1 IgG levels at recruitment were positively associated with infection at delivery (p-values: 0.010, 0.003, and 0.023, respectively), suggesting that they are markers of malaria exposure. Peripheral blood mononuclear cells from Pv-infected women presented fewer CD8+IFN-γ+ T cells and secreted more G-CSF and IL-4 independently of the stimulus used in vitro. Functional anti-PvDBP levels at recruitment had a positive association with birth weight (difference per doubling antibody levels: 45 g, p-value: 0.046). Thus, naturally acquired binding-inhibitory antibodies to PvDBP might confer protection against poor outcomes of Pv malaria in pregnancy.
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Affiliation(s)
- Pilar Requena
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | | | | | - Flor E Martínez-Espinosa
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil; Instituto Leônidas e Maria Deane (ILMD/Fiocruz Amazonia), Amazonia, Brazil
| | - Norma Padilla
- Centro de Estudios en Salud, Universidad del Valle de Guatemala , Guatemala City , Guatemala
| | - Camila Bôtto-Menezes
- Instituto Leônidas e Maria Deane (ILMD/Fiocruz Amazonia), Amazonia, Brazil; Universidade do Estado do Amazonas, Manaus, Amazonas, Brazil
| | - Adriana Malheiro
- Instituto de Ciências Biológicas, Universidade Federal do Amazonas , Manaus , Brazil
| | - Dhiraj Hans
- International Center for Genetic Engineering and Biotechnology , Delhi , India
| | | | - Leanne Robinson
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea; Macfarlane Burnet Institute of Medical Research, Melbourne, VIC, Australia; Walter and Eliza Hall Institute, Parkville, VIC, Australia
| | - Paula Samol
- Papua New Guinea Institute of Medical Research , Madang , Papua New Guinea
| | - Swati Kochar
- Medical College Bikaner , Bikaner, Rajasthan , India
| | | | | | - Meghna Desai
- Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Malaria Branch , Atlanta, GA , USA
| | - Sergi Sanz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | - Llorenç Quintó
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | - Alfredo Mayor
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | | | - Ivo Mueller
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Catalonia, Spain; Walter and Eliza Hall Institute, Parkville, VIC, Australia
| | | | - Hernando A Del Portillo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Catalonia, Spain; ICREA, Barcelona, Spain
| | - Azucena Bardají
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | - Chetan C Chitnis
- International Center for Genetic Engineering and Biotechnology , Delhi , India
| | - Clara Menéndez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
| | - Carlota Dobaño
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona , Barcelona, Catalonia , Spain
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38
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Gueneuc A, Deloron P, Bertin GI. Usefulness of a biomarker to identify placental dysfunction in the context of malaria. Malar J 2017; 16:11. [PMID: 28049536 PMCID: PMC5209802 DOI: 10.1186/s12936-016-1664-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 12/21/2016] [Indexed: 11/25/2022] Open
Abstract
In most tropical areas, pregnant women are at increased risk of malaria, as a consequence of the massive sequestration of parasitized red blood cells in the placenta. The placenta plays a key role in embryonic and fetal development as well as in maternal-fetal exchanges, and pregnancy-associated malaria may alter selected placenta functions that lead to stillbirth and low birth weight. Although there are several tools (blood smear examination, RDT, PCR) to diagnose malaria infection during pregnancy, there is currently no test to assess placenta dysfunction in the framework of pregnancy-associated malaria. Pregnancy-associated malaria shares many features with preeclampsia, an extensively studied disease. Various biomarkers associated with placental dysfunction have been identified as associated with preeclampsia. Several of these are inflammatory markers that lack of specificity. A few seem more specific of placenta dysfunction, including s-endoglin and sFlt1, increased in the peripheral blood during preeclampsia. The predictive value of these biomarkers should be studied in the context of pregnancy-associated malaria to evaluate their usefulness in identifying placental dysfunction during malaria. These biomarkers should be considered to improve the diagnosis of placental dysfunction during malaria and pregnant women monitoring.
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Affiliation(s)
- Alexandra Gueneuc
- Institute of Research for Development (IRD), UMR216-MERIT, Paris, France.,ComUE Sorbonne Paris Cité, Paris, France.,Obstetrics and Fetal Medicine Department, Necker-Enfants-Malades Hospital, Paris, France
| | - Philippe Deloron
- Institute of Research for Development (IRD), UMR216-MERIT, Paris, France.,ComUE Sorbonne Paris Cité, Paris, France.,DHU Risks in Pregnancy, Paris, France
| | - Gwladys I Bertin
- Institute of Research for Development (IRD), UMR216-MERIT, Paris, France. .,ComUE Sorbonne Paris Cité, Paris, France. .,DHU Risks in Pregnancy, Paris, France.
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39
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Malaria: Biology and Disease. Cell 2016; 167:610-624. [PMID: 27768886 DOI: 10.1016/j.cell.2016.07.055] [Citation(s) in RCA: 439] [Impact Index Per Article: 54.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/17/2016] [Accepted: 07/29/2016] [Indexed: 11/22/2022]
Abstract
Malaria has been a major global health problem of humans through history and is a leading cause of death and disease across many tropical and subtropical countries. Over the last fifteen years renewed efforts at control have reduced the prevalence of malaria by over half, raising the prospect that elimination and perhaps eradication may be a long-term possibility. Achievement of this goal requires the development of new tools including novel antimalarial drugs and more efficacious vaccines as well as an increased understanding of the disease and biology of the parasite. This has catalyzed a major effort resulting in development and regulatory approval of the first vaccine against malaria (RTS,S/AS01) as well as identification of novel drug targets and antimalarial compounds, some of which are in human clinical trials.
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40
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Chandrasiri UP, Fowkes FJI, Beeson JG, Richards JS, Kamiza S, Maleta K, Ashorn P, Rogerson SJ. Association between malaria immunity and pregnancy outcomes among Malawian pregnant women receiving nutrient supplementation. Malar J 2016; 15:547. [PMID: 27829430 PMCID: PMC5103486 DOI: 10.1186/s12936-016-1597-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 10/31/2016] [Indexed: 11/24/2022] Open
Abstract
Background Malaria antibody responses measured at delivery have been associated with protection from maternal anaemia and low birth weight deliveries. Whether malarial antibodies present in the first half of pregnancy may protect from these or other poor birth outcomes is unclear. To determine whether malaria antibodies in the first half of pregnancy predict pregnancy outcomes, antibodies were measured to a range of merozoite antigens and to antigens expressed on the surface of parasitized red blood cells (pRBCs) in plasma samples collected at 14–20 weeks of gestation from Malawian women. The latter antibodies were measured as total IgG to pRBCs, and antibodies promoting opsonic phagocytosis of pRBCs. Associations between antibodies and maternal haemoglobin in late pregnancy or newborn size were investigated, after adjusting for potential covariates. Results Antibodies to pRBC surface antigens were associated with higher haemoglobin concentration at 36 weeks. Total IgG to pRBCs was associated with 0.4 g/l [(95% confidence interval (0.04, 0.8)] increase in haemoglobin, and opsonizing antibody with 0.5 (0.05, 0.9) increase in haemoglobin for each 10% increase in antibody. These antibodies were not associated with birthweight, placental malaria, or newborn anthropometrics. Antibodies to merozoite antigens and non-placental-binding IEs were not associated with decreased risk of any of these outcomes. In some instances, they were negatively associated with outcomes of interest. Conclusion Antibodies to placental-binding infected erythrocytes may be associated with higher haemoglobin levels in pregnancy, whereas antibodies to other malaria antigens may instead be markers of malaria exposure. Trial registration clinicaltrials.gov NCT01239693. Registered Nov 10, 2010.
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Affiliation(s)
- Upeksha P Chandrasiri
- Department of Medicine at the Doherty Institute of Infection and Immunity, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, Australia
| | - Freya J I Fowkes
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Prahran, VIC, Australia.,Department of Epidemiology, Centre for Epidemiology and Biostatistics, University of Melbourne, Melbourne, VIC, Australia.,Department of Preventive Medicine and Infectious Diseases, Monash University, Clayton, VIC, Australia
| | - James G Beeson
- Department of Medicine at the Doherty Institute of Infection and Immunity, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, Australia.,Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Prahran, VIC, Australia.,Department of Microbiology, Monash University, Clayton, VIC, Australia
| | - Jack S Richards
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Prahran, VIC, Australia.,Department of Microbiology, Monash University, Clayton, VIC, Australia
| | - Steve Kamiza
- University of Malawi College of Medicine, Blantyre, Malawi
| | - Kenneth Maleta
- Faculty of Public Health and Family Medicine, University of Malawi College of Medicine, Blantyre, Malawi
| | - Per Ashorn
- Centre for Child Health Research, University of Tampere School of Medicine and Tampere University Hospital, Tampere, Finland.,Department of Paediatrics, Tampere University Hospital, Tampere, Finland
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute of Infection and Immunity, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, Australia.
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41
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Odorizzi PM, Feeney ME. Impact of In Utero Exposure to Malaria on Fetal T Cell Immunity. Trends Mol Med 2016; 22:877-888. [PMID: 27614925 DOI: 10.1016/j.molmed.2016.08.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 01/10/2023]
Abstract
Pregnancy-associated malaria, including placental malaria, causes significant morbidity and mortality worldwide. Recently, it has been suggested that in utero exposure of the fetus to malaria antigens may negatively impact the developing immune system and result in tolerance to malaria. Here, we review our current knowledge of fetal immunity to malaria, focusing on the dynamic interactions between maternal malaria infection, placental development, and the fetal immune system. A better understanding of the long-term impact of in utero malaria exposure on the development of natural immunity to malaria, immune responses to other childhood pathogens, and vaccine immunogenicity is urgently needed. This may guide the implementation of novel chemoprevention strategies during pregnancy and facilitate the push toward malaria vaccines.
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Affiliation(s)
- Pamela M Odorizzi
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA, USA
| | - Margaret E Feeney
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA, USA; Department of Pediatrics, University of California, San Francisco, San Francisco, CA, USA.
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42
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McLean ARD, Boel ME, McGready R, Ataide R, Drew D, Tsuboi T, Beeson JG, Nosten F, Simpson JA, Fowkes FJI. Antibody responses to Plasmodium falciparum and Plasmodium vivax blood-stage and sporozoite antigens in the postpartum period. Sci Rep 2016; 6:32159. [PMID: 27558000 PMCID: PMC4997260 DOI: 10.1038/srep32159] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 08/03/2016] [Indexed: 11/17/2022] Open
Abstract
During pregnancy a variety of immunological changes occur to accommodate the fetus. It is unknown whether these changes continue to affect humoral immunity postpartum or how quickly they resolve. IgG levels were measured to P. falciparum and P. vivax antigens in 201 postpartum and 201 controls over 12 weeks. Linear mixed-effects models assessed antibody maintenance over time and the effect of microscopically confirmed Plasmodium spp. infection on antibody levels, and whether this was different in postpartum women compared with control women. Postpartum women had reduced Plasmodium spp. antibody levels compared to controls at baseline. Over 12 weeks, mean antibody levels in postpartum women increased to levels observed in control women. Microscopically confirmed P. falciparum and P. vivax infections during follow-up were associated with an increase in species-specific antibodies with similar magnitudes of boosting observed in postpartum and control women. Antibodies specific for pregnancy-associated, VAR2CSA-expressing parasites did not rapidly decline postpartum and did not boost in response to infection in either postpartum or control women. After pregnancy, levels of malaria-specific antibodies were reduced, but recovered to levels seen in control women. There was no evidence of an impaired ability to mount a boosting response in postpartum women.
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Affiliation(s)
- Alistair R D McLean
- Macfarlane Burnet Institute of Medical Research, Melbourne 3004, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne 3004, Australia
| | - Machteld E Boel
- Shoklo Malaria Research Unit (SMRU), Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot 63110, Thailand
| | - Rose McGready
- Shoklo Malaria Research Unit (SMRU), Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot 63110, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX1 2JD, UK
| | - Ricardo Ataide
- Macfarlane Burnet Institute of Medical Research, Melbourne 3004, Australia
| | - Damien Drew
- Macfarlane Burnet Institute of Medical Research, Melbourne 3004, Australia
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyuma 790-8577, Japan
| | - James G Beeson
- Macfarlane Burnet Institute of Medical Research, Melbourne 3004, Australia.,Department of Microbiology, Monash University 3800, Australia
| | - François Nosten
- Shoklo Malaria Research Unit (SMRU), Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot 63110, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX1 2JD, UK
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne 3004, Australia
| | - Freya J I Fowkes
- Macfarlane Burnet Institute of Medical Research, Melbourne 3004, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne 3004, Australia.,Department of Epidemiology and Preventative Medicine, Monash University 3800, Victoria, Australia
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43
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Long CA, Zavala F. Malaria vaccines and human immune responses. Curr Opin Microbiol 2016; 32:96-102. [PMID: 27262417 PMCID: PMC4983510 DOI: 10.1016/j.mib.2016.04.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 04/11/2016] [Indexed: 12/31/2022]
Abstract
Despite reductions in malaria episodes and deaths over the past decade, there is still significant need for more effective tools to combat this serious global disease. The positive results with the Phase III trial of RTS,S directed to the circumsporozoite protein of Plasmodium falciparum have established that a vaccine against malaria can provide partial protection to children in endemic areas, but its limited efficacy and relatively short window of protection mandate that new generations of more efficacious vaccines must be sought. Evidence shows that anti-parasite immune responses can control infection against other stages as well, but translating these experimental findings into vaccines for blood stages has been disappointing and clinical efforts to test a transmission blocking vaccine are just beginning. Difficulties include the biological complexity of the organism with a large array of stage-specific genes many of which in the erythrocytic stages are antigenically diverse. In addition, it appears necessary to elicit high and long-lasting antibody titers, address the redundant pathways of merozoite invasion, and still seek surrogate markers of protective immunity. Most vaccine studies have focused on a single or a few antigens with an apparent functional role, but this is likely to be too restrictive, and broad, multi-antigen, multi-stage vaccines need further investigation. Finally, novel tools and biological insights involving parasite sexual stages and the mosquito vector will provide new avenues for reducing or blocking malaria transmission.
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Affiliation(s)
- Carole A. Long
- Laboratory of Malaria and Vector Research, 12735 Twinbrook Parkway, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, MD 20852, Phone 301-761-5058, FAX 301-443-5778,
| | - Fidel Zavala
- Dept. of Molecular Microbiology and Immunology, Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD 21205, Phone 443-287-1769, FAX 410-955-0105,
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Yanow SK, Gavina K, Gnidehou S, Maestre A. Impact of Malaria in Pregnancy as Latin America Approaches Elimination. Trends Parasitol 2016; 32:416-427. [PMID: 26875608 DOI: 10.1016/j.pt.2016.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 01/14/2016] [Accepted: 01/19/2016] [Indexed: 11/29/2022]
Abstract
In Latin America, four million pregnancies are at risk of malaria annually, but malaria in pregnancy is largely overlooked. As countries progress toward malaria elimination, targeting reservoirs of transmission is a priority. Pregnant women are an important risk group because they harbor asymptomatic infections and dormant liver stages of Plasmodium vivax that cause relapses. Of significant concern is the discovery that most infections in pregnant women fail to be detected by routine diagnostics. We review here recent findings on malaria in pregnancy within Latin America. We focus on the Amazon basin and Northwest Colombia, areas that harbor the greatest burden of malaria, and propose that more sensitive diagnostics and active surveillance at antenatal clinics will be necessary to eliminate malaria from these final frontiers.
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Affiliation(s)
- Stephanie K Yanow
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada; Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.
| | - Kenneth Gavina
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Sedami Gnidehou
- Department of Biology, Campus Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Amanda Maestre
- Grupo Salud y Comunidad, Universidad de Antioquia, Medellín, Colombia
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Ruizendaal E, van Leeuwen E, Mens PF. Peripheral and placental biomarkers in women with placental malaria: a systematic review. Biomark Med 2015; 9:217-39. [PMID: 25731209 DOI: 10.2217/bmm.14.117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Placental malaria (PM) causes significant morbidity in mothers and infants. Diagnosis of PM during pregnancy is however problematic due to placental sequestration of parasites. Host biomarkers may therefore be used as a diagnostic method. In this systematic review most studies focused on inflammatory markers. A trend was observed for increased IL-10 and TNF-α in PM positives. These markers are however unspecific, thus a combination of multiple biomarkers involved in different pathophysiological pathways of PM is indicated. Of interest are inflammatory markers (TNF-R2, CXCL-13), markers of lipid metabolism (APO-B), angiogenesis (sFlt-1) and hormones (estradiol). As the majority of published studies tested biomarker levels only at delivery, more longitudinal cohort studies will be necessary to detect biomarkers during pregnancy that can predict PM.
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Affiliation(s)
- Esmée Ruizendaal
- KIT Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, The Netherlands
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Mayor A, Bardají A, Macete E, Nhampossa T, Fonseca AM, González R, Maculuve S, Cisteró P, Rupérez M, Campo J, Vala A, Sigaúque B, Jiménez A, Machevo S, de la Fuente L, Nhama A, Luis L, Aponte JJ, Acácio S, Nhacolo A, Chitnis C, Dobaño C, Sevene E, Alonso PL, Menéndez C. Changing Trends in P. falciparum Burden, Immunity, and Disease in Pregnancy. N Engl J Med 2015; 373:1607-17. [PMID: 26488692 DOI: 10.1056/nejmoa1406459] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Prevention of reinfection and resurgence is an integral component of the goal to eradicate malaria. However, the adverse effects of malaria resurgences are not known. METHODS We assessed the prevalence of Plasmodium falciparum infection among 1819 Mozambican women who delivered infants between 2003 and 2012. We used microscopic and histologic examination and a quantitative polymerase-chain-reaction (qPCR) assay, as well as flow-cytometric analysis of IgG antibody responses against two parasite lines. RESULTS Positive qPCR tests for P. falciparum decreased from 33% in 2003 to 2% in 2010 and increased to 6% in 2012, with antimalarial IgG antibody responses mirroring these trends. Parasite densities in peripheral blood on qPCR assay were higher in 2010-2012 (geometric mean [±SD], 409±1569 genomes per microliter) than in 2003-2005 (44±169 genomes per microliter, P=0.02), as were parasite densities in placental blood on histologic assessment (50±39% of infected erythrocytes vs. 4±6%, P<0.001). The malaria-associated reduction in maternal hemoglobin levels was larger in 2010-2012 (10.1±1.8 g per deciliter in infected women vs. 10.9±1.7 g per deciliter in uninfected women; mean difference, -0.82 g per deciliter; 95% confidence interval [CI], -1.39 to -0.25) than in 2003-2005 (10.5±1.1 g per deciliter vs. 10.6±1.5 g per deciliter; difference, -0.12 g per deciliter; 95% CI, -0.67 to 0.43), as was the reduction in birth weight (2863±440 g in women with past or chronic infections vs. 3070±482 g in uninfected women in 2010-2012; mean difference, -164.5 g; 95% CI, -289.7 to -39.4; and 2994±487 g vs. 3117±455 g in 2003-2005; difference, -44.8 g; 95% CI, -139.1 to 49.5). CONCLUSIONS Antimalarial antibodies were reduced and the adverse consequences of P. falciparum infections were increased in pregnant women after 5 years of a decline in the prevalence of malaria. (Funded by Malaria Eradication Scientific Alliance and others.).
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Affiliation(s)
- Alfredo Mayor
- From the Barcelona Institute for Global Health (ISGlobal), Barcelona Center for International Health Research (CRESIB), and Hospital Clínic-Universitat de Barcelona (A.M., A.B., A.M.F., R.G., P.C., M.R., J.C., A.J., L.F., J.J.A., C.D., P.L.A., C.M.), Barcelona, and Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBEREsp), Madrid (A.J.) - all in Spain; Centro de Investigação em Saúde da Manhiça (CISM) (A.M., A.B., E.M., T.N., R.G., S. Maculuve, M.R., A.V., B.S., S. Machevo, A. Nhama, L.L., J.J.A., S.A., A. Nhacolo, C.D., E.S., P.L.A., C.M.), Instituto Nacional de Saúde, Ministry of Health (T.N., S. Maculuve, B.S., A. Nhama, S.A.), and Faculdade de Medicina, Universidade Eduardo Mondlane (S. Machevo, E.S.) - all in Maputo, Mozambique; the Graduate Program in Areas of Basic and Applied Biology, Universidade do Porto, Porto, Portugal (A.M.F.); and the International Center for Genetic Engineering and Biotechnology, New Delhi, India (C.C.)
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From within host dynamics to the epidemiology of infectious disease: Scientific overview and challenges. Math Biosci 2015; 270:143-55. [PMID: 26474512 DOI: 10.1016/j.mbs.2015.10.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Since their earliest days, humans have been struggling with infectious diseases. Caused by viruses, bacteria, protozoa, or even higher organisms like worms, these diseases depend critically on numerous intricate interactions between parasites and hosts, and while we have learned much about these interactions, many details are still obscure. It is evident that the combined host-parasite dynamics constitutes a complex system that involves components and processes at multiple scales of time, space, and biological organization. At one end of this hierarchy we know of individual molecules that play crucial roles for the survival of a parasite or for the response and survival of its host. At the other end, one realizes that the spread of infectious diseases by far exceeds specific locales and, due to today's easy travel of hosts carrying a multitude of organisms, can quickly reach global proportions. The community of mathematical modelers has been addressing specific aspects of infectious diseases for a long time. Most of these efforts have focused on one or two select scales of a multi-level disease and used quite different computational approaches. This restriction to a molecular, physiological, or epidemiological level was prudent, as it has produced solid pillars of a foundation from which it might eventually be possible to launch comprehensive, multi-scale modeling efforts that make full use of the recent advances in biology and, in particular, the various high-throughput methodologies accompanying the emerging -omics revolution. This special issue contains contributions from biologists and modelers, most of whom presented and discussed their work at the workshop From within Host Dynamics to the Epidemiology of Infectious Disease, which was held at the Mathematical Biosciences Institute at Ohio State University in April 2014. These contributions highlight some of the forays into a deeper understanding of the dynamics between parasites and their hosts, and the consequences of this dynamics for the spread and treatment of infectious diseases.
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van Eijk AM, Hill J, Noor AM, Snow RW, ter Kuile FO. Prevalence of malaria infection in pregnant women compared with children for tracking malaria transmission in sub-Saharan Africa: a systematic review and meta-analysis. LANCET GLOBAL HEALTH 2015; 3:e617-28. [PMID: 26296450 PMCID: PMC4673091 DOI: 10.1016/s2214-109x(15)00049-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/30/2015] [Accepted: 05/19/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND In malarious areas, pregnant women are more likely to have detectable malaria than are their non-pregnant peers, and the excess risk of infection varies with gravidity. Pregnant women attending antenatal clinic for their first visit are a potential pragmatic sentinel group to track the intensity of malaria transmission; however, the relation between malaria prevalence in children, a standard measure to estimate malaria endemicity, and pregnant women has never been compared. METHODS We obtained data on malaria prevalence in pregnancy from the Malaria in Pregnancy Library (January, 2015) and data for children (0-59 months) were obtained from recently published work on parasite prevalence in Africa and the Malaria in Pregnancy Library. We used random effects meta-analysis to obtain a pooled prevalence ratio (PPR) of malaria in children versus pregnant women (during pregnancy, not at delivery) and by gravidity, and we used meta-regression to assess factors affecting the prevalence ratio. FINDINGS We used data from 18 sources that included 57 data points. There was a strong linear relation between the prevalence of malaria infection in pregnant women and children (r=0·87, p<0·0001). Prevalence was higher in children when compared with all gravidae (PPR=1·44, 95% CI 1·29-1·62; I(2)=80%, 57 studies), and against multigravidae (1·94, 1·68-2·24; I(2)=80%, 7 studies), and marginally higher against primigravidae (1·16, 1·05-1·29; I(2)=48%, 8 studies). PPR was higher in areas of higher transmission. INTERPRETATION Malaria prevalence in pregnant women is strongly correlated with prevalence data in children obtained from household surveys, and could provide a pragmatic adjunct to survey strategies to track trends in malaria transmission in Africa. FUNDING The Malaria in Pregnancy Consortium, which is funded through a grant from the Bill & Melinda Gates Foundation to the Liverpool School of Tropical Medicine, UK; US Centers for Disease Control and Prevention; and Wellcome Trust, UK.
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Affiliation(s)
- Anna M van Eijk
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Jenny Hill
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Abdisalan M Noor
- Spatial Health Metrics Group, Department of Public Health Research, KEMRI-Wellcome Trust Research Program, Nairobi, Kenya; Centre for Tropical Medicine & Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Centre for Clinical Vaccinology and Tropical Medicine, Oxford, UK
| | - Robert W Snow
- Spatial Health Metrics Group, Department of Public Health Research, KEMRI-Wellcome Trust Research Program, Nairobi, Kenya; Centre for Tropical Medicine & Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Centre for Clinical Vaccinology and Tropical Medicine, Oxford, UK
| | - Feiko O ter Kuile
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
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McLEAN ARD, ATAIDE R, SIMPSON JA, BEESON JG, FOWKES FJI. Malaria and immunity during pregnancy and postpartum: a tale of two species. Parasitology 2015; 142:999-1015. [PMID: 25731914 PMCID: PMC4453920 DOI: 10.1017/s0031182015000074] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 12/19/2014] [Accepted: 01/16/2015] [Indexed: 11/07/2022]
Abstract
It is well established that pregnant women are at an increased risk of Plasmodium falciparum infection when compared to non-pregnant individuals and limited epidemiological data suggest Plasmodium vivax risk also increases with pregnancy. The risk of P. falciparum declines with successive pregnancies due to the acquisition of immunity to pregnancy-specific P. falciparum variants. However, despite similar declines in P. vivax risk with successive pregnancies, there is a paucity of evidence P. vivax-specific immunity. Cross-species immunity, as well as immunological and physiological changes that occur during pregnancy may influence the susceptibility to both P. vivax and P. falciparum. The period following delivery, the postpartum period, is relatively understudied and available epidemiological data suggests that it may also be a period of increased risk of infection to Plasmodium spp. Here we review the literature and directly compare and contrast the epidemiology, clinical pathogenesis and immunological features of P. vivax and P. falciparum in pregnancy, with a particular focus on studies performed in areas co-endemic for both species. Furthermore, we review the intriguing epidemiology literature of both P. falciparum and P. vivax postpartum and relate observations to the growing literature pertaining to malaria immunology in the postpartum period.
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Affiliation(s)
- A. R. D. McLEAN
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - R. ATAIDE
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
| | - J. A. SIMPSON
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - J. G. BEESON
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - F. J. I. FOWKES
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Epidemiology and Preventive Medicine and Department of Infectious Diseases, Monash University, Commercial Road, Melbourne, Victoria 3004, Australia
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Abstract
INTRODUCTION Placental malaria (PM) is a major public health problem that constitutes a significant health concern for the mother, and especially for the developing fetus and offspring. Current means of prevention have limitations, including a restricted window of intervention that excludes the first trimester of pregnancy, and the fact that very few drugs can be used for this purpose. The identification of the VAR2CSA antigen, specific to PM parasites, offers an excellent opportunity to develop a vaccine against this disease. Proof of concept of a first-generation vaccine is nearing completion, and two clinical trials are underway. AREAS COVERED This review focuses on PM, which is mainly caused by Plasmodium falciparum. The review highlights recent advances and the key milestones that led to the identification of the optimal vaccine target within the large VAR2CSA protein. The paper also points out how future improvements can strengthen this process to achieve an effective vaccine in the field. EXPERT OPINION The approach taken to develop a P. falciparum erythrocyte membrane protein 1-based vaccine to protect pregnant women is very promising in view of the current difficulties of achieving a sterilizing vaccine against malaria parasite. This approach could help us to control the deleterious effect of malaria infections that characterize severe clinical forms.
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