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Rojas-Pirela M, Medina L, Rojas MV, Liempi AI, Castillo C, Pérez-Pérez E, Guerrero-Muñoz J, Araneda S, Kemmerling U. Congenital Transmission of Apicomplexan Parasites: A Review. Front Microbiol 2021; 12:751648. [PMID: 34659187 PMCID: PMC8519608 DOI: 10.3389/fmicb.2021.751648] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 09/01/2021] [Indexed: 12/17/2022] Open
Abstract
Apicomplexans are a group of pathogenic protists that cause various diseases in humans and animals that cause economic losses worldwide. These unicellular eukaryotes are characterized by having a complex life cycle and the ability to evade the immune system of their host organism. Infections caused by some of these parasites affect millions of pregnant women worldwide, leading to various adverse maternal and fetal/placental effects. Unfortunately, the exact pathogenesis of congenital apicomplexan diseases is far from being understood, including the mechanisms of how they cross the placental barrier. In this review, we highlight important aspects of the diseases caused by species of Plasmodium, Babesia, Toxoplasma, and Neospora, their infection during pregnancy, emphasizing the possible role played by the placenta in the host-pathogen interaction.
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Affiliation(s)
- Maura Rojas-Pirela
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.,Facultad de Farmacia y Bioanálisis, Universidad de Los Andes, Mérida, Venezuela
| | - Lisvaneth Medina
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Maria Verónica Rojas
- Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Ana Isabel Liempi
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Christian Castillo
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Núcleo de Investigación Aplicada en Ciencias Veterinarias y Agronómicas, Facultad de Medicina Veterinaria y Agronomía, Universidad de Las Américas, Santiago, Chile
| | | | - Jesús Guerrero-Muñoz
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Sebastian Araneda
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Facultad de Salud y Odontología, Universidad Diego Portales, Santiago, Chile
| | - Ulrike Kemmerling
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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Odorizzi PM, Jagannathan P, McIntyre TI, Budker R, Prahl M, Auma A, Burt TD, Nankya F, Nalubega M, Sikyomu E, Musinguzi K, Naluwu K, Kakuru A, Dorsey G, Kamya MR, Feeney ME. In utero priming of highly functional effector T cell responses to human malaria. Sci Transl Med 2019; 10:10/463/eaat6176. [PMID: 30333241 DOI: 10.1126/scitranslmed.aat6176] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/10/2018] [Accepted: 09/17/2018] [Indexed: 12/14/2022]
Abstract
Malaria remains a significant cause of morbidity and mortality worldwide, particularly in infants and children. Some studies have reported that exposure to malaria antigens in utero results in the development of tolerance, which could contribute to poor immunity to malaria in early life. However, the effector T cell response to pathogen-derived antigens encountered in utero, including malaria, has not been well characterized. Here, we assessed the frequency, phenotype, and function of cord blood T cells from Ugandan infants born to mothers with and without placental malaria. We found that infants born to mothers with active placental malaria had elevated frequencies of proliferating effector memory fetal CD4+ T cells and higher frequencies of CD4+ and CD8+ T cells that produced inflammatory cytokines. Fetal CD4+ and CD8+ T cells from placental malaria-exposed infants exhibited greater in vitro proliferation to malaria antigens. Malaria-specific CD4+ T cell proliferation correlated with prospective protection from malaria during childhood. These data demonstrate that placental malaria is associated with the generation of proinflammatory malaria-responsive fetal T cells. These findings add to our current understanding of fetal immunity and indicate that a functional and protective pathogen-specific T cell response can be generated in utero.
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Affiliation(s)
- Pamela M Odorizzi
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | | | - Tara I McIntyre
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Rachel Budker
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Mary Prahl
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Ann Auma
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Trevor D Burt
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA.,Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143, USA
| | | | | | - Esther Sikyomu
- Infectious Disease Research Collaboration, Kampala, Uganda
| | | | - Kate Naluwu
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Abel Kakuru
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Moses R Kamya
- School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Margaret E Feeney
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA. .,Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA
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3
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Harrington WE, Kakuru A, Jagannathan P. Malaria in pregnancy shapes the development of foetal and infant immunity. Parasite Immunol 2018; 41:e12573. [PMID: 30019470 DOI: 10.1111/pim.12573] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 05/21/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022]
Abstract
Malaria, particularly Plasmodium falciparum, continues to disproportionately affect pregnant women. In addition to the profoundly deleterious impact of maternal malaria on the health of the mother and foetus, malaria infection in pregnancy has been shown to affect the development of the foetal and infant immune system and may alter the risk of malaria and nonmalarial outcomes during infancy. This review summarizes our current understanding of how malaria infection in pregnancy shapes the protective components of the maternal immune system transferred to the foetus and how foetal exposure to parasite antigens impacts the development of foetal and infant immunity. It also reviews existing evidence linking malaria infection in pregnancy to malaria and nonmalarial outcomes in infancy and how preventing malaria in pregnancy may alter these outcomes. A better understanding of the consequences of malaria infection in pregnancy on the development of foetal and infant immunity will inform control strategies, including intermittent preventive treatment in pregnancy and vaccine development.
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Affiliation(s)
- Whitney E Harrington
- Department of Pediatrics, University of Washington/Seattle Children's Hospital, Seattle, Washington
| | - Abel Kakuru
- Infectious Diseases Research Collaboration, Kampala, Uganda
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4
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Ourives SS, Borges QI, Dos Santos DSA, Melo ECM, de Souza RM, Damazo AS. Analysis of the lymphocyte cell population during malaria caused by Plasmodium vivax and its correlation with parasitaemia and thrombocytopaenia. Malar J 2018; 17:303. [PMID: 30126413 PMCID: PMC6102853 DOI: 10.1186/s12936-018-2443-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 08/04/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The mechanisms of activation and regulation of T lymphocytes and their cytokines in malaria caused by Plasmodium vivax are complex and poorly understood. Previous data suggest that T cells balance protective immune responses with immune mediated pathology in malaria. This study investigates the lymphocytic profile of patients infected with P. vivax by identifying and quantifying the specific sub-populations of Th1, Th2, Th17 and Treg cells and observing the correlation between parasitaemia and the number of platelets. METHODS A cross-sectional study was carried out in an endemic area of the state of Acre, Brazil. In order to obtain identification and quantification of lymphocyte sub-populations through flow cytometry, blood samples were collected from 50 individuals infected with P. vivax and 20 non-infected controls. To differentiate Th1 from Th2, the presence of cytokines IL-4 and TNF was examined by enzyme-linked immunosorbent assay. Utilizing the Mann-Whitney and Spearman coefficient tests, comparison and correlation analysis were rendered to test the parasitaemia and the number of platelets relationship. RESULTS The data indicate that individuals infected with P. vivax present a significant reduction in Th1, Th2 and Th17 cell sub-populations when compared to the non-infected control group. A negative correlation exists between parasitaemia and platelet counts in individuals infected with P. vivax. There is no correlation of parasitaemia or thrombocytopaenia with any sub-population of T lymphocytes analysed. Interestingly, patients with serum Th1 cytokine profile present inversely proportional parasitaemia to the increase in the number of Th1, Th2, Th17 and Treg cells while patients with serum Th2 cytokine profile present directly proportional parasitaemia to the increase in number of Th1 and Th2 cells. Regarding the number of platelets, patients with serum Th1 cytokine profile show a correlation directly proportional to the Th17 sub-population. In contrast, platelet counts are directly proportional only to Treg and activated Treg cells in patients with serum Th2 cytokine profile. CONCLUSIONS During the P. vivax infection patients with serum Th1 versus Th2 cytokine profile present different biological mechanisms for activating the immune system against parasite load.
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Affiliation(s)
- Samantha Soares Ourives
- Faculty of Medicine (FM), Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, 78060-900, Brazil
| | - Quessi Irias Borges
- Faculty of Medicine (FM), Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, 78060-900, Brazil
| | | | | | - Rodrigo Medeiros de Souza
- Centre for Health Sciences and Sport, Federal University of Acre (UFAC), Cruzeiro do Sul, AC, 69980000, Brazil
| | - Amílcar Sabino Damazo
- Faculty of Medicine (FM), Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, 78060-900, Brazil. .,Department of Basic Science in Health Faculty of Medicine (FM), Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso, 78060-900, Brazil.
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5
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Timing of in utero malaria exposure influences fetal CD4 T cell regulatory versus effector differentiation. Malar J 2016; 15:497. [PMID: 27717402 PMCID: PMC5055709 DOI: 10.1186/s12936-016-1545-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 10/04/2016] [Indexed: 11/26/2022] Open
Abstract
Background In malaria-endemic areas, the first exposure to malaria antigens often occurs in utero when the fetal immune system is poised towards the development of tolerance. Children exposed to placental malaria have an increased risk of clinical malaria in the first few years of life compared to unexposed children. Recent work has suggested the potential of pregnancy-associated malaria to induce immune tolerance in children living in malaria-endemic areas. A study was completed to evaluate the effect of malaria exposure during pregnancy on fetal immune tolerance and effector responses. Methods Using cord blood samples from a cohort of mother-infant pairs followed from early in pregnancy until delivery, flow cytometry analysis was completed to assess the relationship between pregnancy-associated malaria and fetal cord blood CD4 and dendritic cell phenotypes. Results Cord blood FoxP3+ Treg counts were higher in infants born to mothers with Plasmodium parasitaemia early in pregnancy (12–20 weeks of gestation; p = 0.048), but there was no association between Treg counts and the presence of parasites in the placenta at the time of delivery (by loop-mediated isothermal amplification (LAMP); p = 0.810). In contrast, higher frequencies of activated CD4 T cells (CD25+FoxP3−CD127+) were observed in the cord blood of neonates with active placental Plasmodium infection at the time of delivery (p = 0.035). This population exhibited evidence of effector memory differentiation, suggesting priming of effector T cells in utero. Lastly, myeloid dendritic cells were higher in the cord blood of infants with histopathologic evidence of placental malaria (p < 0.0001). Conclusion Together, these data indicate that in utero exposure to malaria drives expansion of both regulatory and effector T cells in the fetus, and that the timing of this exposure has a pivotal role in determining the polarization of the fetal immune response.
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6
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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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7
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Nouatin O, Gbédandé K, Ibitokou S, Vianou B, Houngbegnon P, Ezinmegnon S, Borgella S, Akplogan C, Cottrell G, Varani S, Massougbodji A, Moutairou K, Troye-Blomberg M, Deloron P, Luty AJF, Fievet N. Infants' Peripheral Blood Lymphocyte Composition Reflects Both Maternal and Post-Natal Infection with Plasmodium falciparum. PLoS One 2015; 10:e0139606. [PMID: 26580401 PMCID: PMC4651557 DOI: 10.1371/journal.pone.0139606] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 09/14/2015] [Indexed: 11/19/2022] Open
Abstract
Maternal parasitoses modulate fetal immune development, manifesting as altered cellular immunological activity in cord blood that may be linked to enhanced susceptibility to infections in early life. Plasmodium falciparum typifies such infections, with distinct placental infection-related changes in cord blood exemplified by expanded populations of parasite antigen-specific regulatory T cells. Here we addressed whether such early-onset cellular immunological alterations persist through infancy. Specifically, in order to assess the potential impacts of P. falciparum infections either during pregnancy or during infancy, we quantified lymphocyte subsets in cord blood and in infants' peripheral blood during the first year of life. The principal age-related changes observed, independent of infection status, concerned decreases in the frequencies of CD4+, NKdim and NKT cells, whilst CD8+, Treg and Teff cells' frequencies increased from birth to 12 months of age. P. falciparum infections present at delivery, but not those earlier in gestation, were associated with increased frequencies of Treg and CD8+ T cells but fewer CD4+ and NKT cells during infancy, thus accentuating the observed age-related patterns. Overall, P. falciparum infections arising during infancy were associated with a reversal of the trends associated with maternal infection i.e. with more CD4+ cells, with fewer Treg and CD8+ cells. We conclude that maternal P. falciparum infection at delivery has significant and, in some cases, year-long effects on the composition of infants' peripheral blood lymphocyte populations. Those effects are superimposed on separate and independent age- as well as infant infection-related alterations that, respectively, either match or run counter to them.
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MESH Headings
- Adult
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Benin
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Female
- Fetal Blood/immunology
- Fetal Blood/parasitology
- Humans
- Immunophenotyping
- Infant
- Killer Cells, Natural/immunology
- Killer Cells, Natural/pathology
- Lymphocyte Count
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/pathology
- Natural Killer T-Cells/immunology
- Natural Killer T-Cells/pathology
- Placenta/immunology
- Placenta/parasitology
- Placenta/pathology
- Plasmodium falciparum/immunology
- Pregnancy
- Pregnancy Complications, Parasitic/immunology
- Pregnancy Complications, Parasitic/parasitology
- Pregnancy Complications, Parasitic/pathology
- Retrospective Studies
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/pathology
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Affiliation(s)
- Odilon Nouatin
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Komi Gbédandé
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Samad Ibitokou
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Bertin Vianou
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Parfait Houngbegnon
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Sem Ezinmegnon
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Sophie Borgella
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Institut de Recherche pour le Développement, MERIT UMR D216 Mère et enfant face aux infections tropicales, Paris, France
| | - Carine Akplogan
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Gilles Cottrell
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Institut de Recherche pour le Développement, MERIT UMR D216 Mère et enfant face aux infections tropicales, Paris, France
- PRES Sorbonne Paris Cité, Université Paris Descartes, Faculté de Pharmacie, Paris, France
| | - Stefania Varani
- Unit of Microbiology, Department of Diagnostic, Experimental and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Achille Massougbodji
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
| | - Kabirou Moutairou
- Département de Biochimie et de Biologie Cellulaire, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Cotonou, Bénin
| | - Marita Troye-Blomberg
- Department of Molecular Biosciences, the Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Philippe Deloron
- Institut de Recherche pour le Développement, MERIT UMR D216 Mère et enfant face aux infections tropicales, Paris, France
- PRES Sorbonne Paris Cité, Université Paris Descartes, Faculté de Pharmacie, Paris, France
| | - Adrian J. F. Luty
- Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Nadine Fievet
- Centre d’Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l’Enfance (CERPAGE), Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou, Benin
- Institut de Recherche pour le Développement, MERIT UMR D216 Mère et enfant face aux infections tropicales, Paris, France
- PRES Sorbonne Paris Cité, Université Paris Descartes, Faculté de Pharmacie, Paris, France
- * E-mail:
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Scholzen A, Cooke BM, Plebanski M. Plasmodium falciparum induces Foxp3hi CD4 T cells independent of surface PfEMP1 expression via small soluble parasite components. Front Microbiol 2014; 5:200. [PMID: 24822053 PMCID: PMC4013457 DOI: 10.3389/fmicb.2014.00200] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 04/15/2014] [Indexed: 01/08/2023] Open
Abstract
Elevated levels of regulatory T cells following Plasmodium infection are a well-reported phenomenon that can influence both protective and pathological anti-parasite responses, and might additionally impact on vaccine responses in acutely malaria infected individuals. The mechanisms underlying their induction or expansion by the parasite, however, are incompletely understood. In a previous study, Plasmodium falciparum infected red blood cells (iRBCs) were shown to induce effector-cytokine producing Foxp3int CD4+ T cells, as well as regulatory Foxp3hi CD4+ T cells in vitro. The aim of the present study was to determine the contribution of parasite components to the induction of Foxp3 expression in human CD4+ T cells. Using the surface PfEMP1-deficient parasite line 1G8, we demonstrate that induction of Foxp3hi and Foxp3int CD4+ T cells is independent of PfEMP1 expression on iRBCs. We further demonstrate that integrity of iRBCs is no requirement for the induction of Foxp3 expression. Finally, transwell experiments showed that induction of Foxp3 expression, and specifically the generation of Foxp3hi as opposed to Foxp3int CD4 T cells, can be mediated by soluble parasite components smaller than 20 nm and thus likely distinct from the malaria pigment hemozoin. These results suggest that the induction of Foxp3hi T cells by P. falciparum is largely independent of two key immune modulatory parasite components, and warrant future studies into the nature of the Foxp3hi inducing parasite components to potentially allow their exclusion from vaccine formulations.
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Affiliation(s)
- Anja Scholzen
- Department of Immunology, Monash University Melbourne, VIC, Australia ; Department of Medical Microbiology, Radboud University Medical Centre Nijmegen, Netherlands
| | - Brian M Cooke
- Department of Microbiology, Monash University Clayton, VIC, Australia
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9
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Staszewski V, Reece SE, O'Donnell AJ, Cunningham EJA. Drug treatment of malaria infections can reduce levels of protection transferred to offspring via maternal immunity. Proc Biol Sci 2012; 279:2487-96. [PMID: 22357264 PMCID: PMC3350664 DOI: 10.1098/rspb.2011.1563] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 02/01/2012] [Indexed: 02/06/2023] Open
Abstract
Maternally transferred immunity can have a fundamental effect on the ability of offspring to deal with infection. However, levels of antibodies in adults can vary both quantitatively and qualitatively between individuals and during the course of infection. How infection dynamics and their modification by drug treatment might affect the protection transferred to offspring remains poorly understood. Using the rodent malaria parasite Plasmodium chabaudi, we demonstrate that curing dams part way through infection prior to pregnancy can alter their immune response, with major consequences for offspring health and survival. In untreated maternal infections, maternally transferred protection suppressed parasitaemia and reduced pup mortality by 75 per cent compared with pups from naïve dams. However, when dams were treated with anti-malarial drugs, pups received fewer maternal antibodies, parasitaemia was only marginally suppressed, and mortality risk was 25 per cent higher than for pups from dams with full infections. We observed the same qualitative patterns across three different host strains and two parasite genotypes. This study reveals the role that within-host infection dynamics play in the fitness consequences of maternally transferred immunity. Furthermore, it highlights a potential trade-off between the health of mothers and offspring suggesting that anti-parasite treatment may significantly affect the outcome of infection in newborns.
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Affiliation(s)
- Vincent Staszewski
- Centre for Infection Immunity and Evolution, University of Edinburgh, Edinburgh EH9 3JT, UK.
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10
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Carlier Y, Truyens C, Deloron P, Peyron F. Congenital parasitic infections: a review. Acta Trop 2012; 121:55-70. [PMID: 22085916 DOI: 10.1016/j.actatropica.2011.10.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 10/27/2011] [Accepted: 10/29/2011] [Indexed: 12/11/2022]
Abstract
This review defines the concepts of maternal-fetal (congenital) and vertical transmissions (mother-to-child) of pathogens and specifies the human parasites susceptible to be congenitally transferred. It highlights the epidemiological features of this transmission mode for the three main congenital parasitic infections due to Toxoplasma gondii, Trypanosoma cruzi and Plasmodium sp. Information on the possible maternal-fetal routes of transmission, the placental responses to infection and timing of parasite transmission are synthesized and compared. The factors susceptible to be involved in parasite transmission and development of congenital parasitic diseases, such as the parasite genotypes, the maternal co-infections and parasitic load, the immunological features of pregnant women and the capacity of some fetuses/neonates to overcome their immunological immaturity to mount an immune response against the transmitted parasites are also discussed and compared. Analysis of clinical data indicates that parasitic congenital infections are often asymptomatic, whereas symptomatic newborns generally display non-specific symptoms. The long-term consequences of congenital infections are also mentioned, such as the imprinting of neonatal immune system and the possible trans-generational transmission. The detection of infection in pregnant women is mainly based on standard serological or parasitological investigations. Amniocentesis and cordocentesis can be used for the detection of some fetal infections. The neonatal infection can be assessed using parasitological, molecular or immunological methods; the place of PCR in such neonatal diagnosis is discussed. When such laboratory diagnosis is not possible at birth or in the first weeks of life, standard serological investigations can also be performed 8-10 months after birth, to avoid detection of maternal transmitted antibodies. The specific aspects of treatment of T. gondii, T. cruzi and Plasmodium congenital infections are mentioned. The possibilities of primary and secondary prophylaxes, as well as the available WHO corresponding recommendations are also presented.
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