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Congenital transmission of Mexican strains of Trypanosoma cruzi TcIa: interaction between parasite and human placental explants
- Cecilia Gomes Barbosa, César Gómez-Hernández, Marcos Vinícius da Silva, Karine Rezende-Oliveira, Paula Tatiana Mutão Ferreira, Ana Carolina Morais de Oliveira, Chamberttan Souza Desidério, Fernanda Rodrigues Helmo, Tamires Marielem de Carvalho-Costa, Ingrid Ketlen Pereira Dos Santos, Lorena Kelly Alves Saraiva, Carlo José Freire de Oliveira, Juliana Reis Machado, Eloisa Amália Vieira Ferro, Virmondes Rodrigues, Jr., Luís Eduardo Ramirez
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- Journal:
- Parasitology / Volume 149 / Issue 3 / March 2022
- Published online by Cambridge University Press:
- 24 November 2021, pp. 418-426
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Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1β, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.
Identification of Leishmania infantum in blood donors from endemic regions for visceral leishmaniasis
- Loren Queli Pereira, Márcia Maria Ferreira-Silva, Cristhianne Molinero Andrade Ratkevicius, César Gómez-Hérnandez, Fernanda Bernadelli De Vito, Sarah Cristina Sato Vaz Tanaka, Virmondes Rodrigues Júnior, Helio Moraes-Souza
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- Journal:
- Parasitology / Volume 148 / Issue 1 / January 2021
- Published online by Cambridge University Press:
- 04 November 2020, pp. 110-114
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Visceral leishmaniasis is an endemic protozoonosis observed in over 60 countries, with over 500 000 new cases recorded annually. Although the diagnostic procedure of its symptomatic forms is well established, for asymptomatic patients, who represent about 85% of those infected, there is no consensus on the best method for its identification. Recent studies have presented molecular techniques as viable identification methods, with good sensitivity and specificity indices in asymptomatic individuals. Therefore, we aimed to use molecular methods to assess their effectiveness in identifying the presence of asymptomatic infection by Leishmania infantum (L. infantum) individuals from endemic regions of Brazil. Screening was performed by real-time polymerase chain reaction (qPCR) and confirmed by sequencing the cytochrome B gene. Of the 127 samples [from 608 blood donors who had participated in a previous study, of which 34 were positive by the enzyme-linked immunosorbent assay (ELISA) rK39] tested by qPCR, 31 (24.4%) were positive. In the sequencing of 10 qPCR-positive samples, five were identified as L. infantum. Complimentary samples of the ELISA rK39 and conventional PCR showed only reasonable and low agreement with qPCR, respectively. The qPCR confirmed the presence of infection in five of the 10 sequenced samples, ELISA confirmed three, and the conventional PCR confirmed none.
Analysis of regulatory T cells and CTLA-4 expression in pregnant women according to seropositivity to Toxoplasma gondii
- Karine Rezende-Oliveira, César Gómez-Hernández, Marcos Vinicius da Silva, Fernanda Rodrigues Helmo, Virmondes Rodrigues
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- Journal:
- Parasitology / Volume 147 / Issue 7 / June 2020
- Published online by Cambridge University Press:
- 18 March 2020, pp. 810-815
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Pregnancy is considered a period in which immunomodulation occurs, although it is important for the maintenance of the foetus, could contribute to infections as Toxoplasma gondii. Immune response cells such as regulatory T cells participate in this immunomodulation, and surface molecules such as CTLA-4 develop an immunosuppressive role, could contribute to the establishment of the parasite. This study aimed to evaluate the presence of regulatory T cells and the expression of CTLA-4 in parturient and non-pregnant seropositive and seronegative for anti-T. gondii antibodies. Sixty-two participants were evaluated, 14 parturient with negative serology, 23 parturient with positive serology, 16 non-pregnant women seronegative and 9 non-pregnant women seropositive. Immunophenotyping was performed for characterize TCD4+Foxp3+ cells, T CD4+CD25-Foxp3+, TCD4+CD25highFoxp3+, TCD4+CTLA-4+, TCD4+CD25-CTLA-4+ and TCD4+CD25highCTLA-4+. We observed a lower level of CD4+CD25highFoxp3+ cells from seropositive parturient compared with seropositive non-pregnant cells. Significative levels of CD4+CD25-Foxp3+ cells from seronegative pregnant were observed compared with seropositive pregnant cells. Furthermore, the higher level of CD4+CD25-CTLA-4+ cells populations was detected in seropositive pregnant cells compared with seropositive non-pregnant. Although a significant increase in CTLA-4 cells was observed in pregnant women positive for anti-T. gondii antibodies, this increase did not cause a risk of reactivation of the infection.
12 - Genetics of human susceptibility to infection and hepatic disease caused by schistosomes
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- By Alain J. Dessein, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Sandrine Marquet, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Carole Eboumbou Moukoko, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Hèlia Dessein, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Laurent Argiro, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Sandrine Henri, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Dominique Hillaire, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Christophe Chevillard, Immunologie et Génétique des Maladies Parasitaires, Institut National de la Santé et de la Recherche Médicale, Laboratoire de Parasitologie-Mycologie, Faculté de Médecine, Marseille, France, Nasureldin El Wali, Institute of Nuclear Medicine and Molecular Biology, University of Gezira, Wad Medani, Sudan, Mubarak Magzoub, Institute of Nuclear Medicine and Molecular Biology, University of Gezira, Wad Medani, Sudan, Laurent Abel, Génétique Humaine des Maladies Infectieuses, Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine Necker, Paris, Virmondes Rodrigues, Jr, Faculty of Medicine do Triangulo Mineiro, Ubéraba, Brazil, Aluizio Prata, Faculty of Medicine do Triangulo Mineiro, Ubéraba, Brazil, Gachuhi Kimani, Kenya Medical Research Institute, Biomedical Sciences Research Centre, Nairobi, Kenya
- Edited by Richard Bellamy, Kintampo Health Research Centre, Ghana
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- Book:
- Susceptibility to Infectious Diseases
- Published online:
- 14 August 2009
- Print publication:
- 22 December 2003, pp 337-360
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Summary
Schistosome infections cause much suffering in millions of people living in tropical regions of Africa, Asia, and South America (Prata, 1987; Chitsulo et al., 2000). The most severe clinical symptoms affect the kidneys and urinary tract. However, schistosomes also cause various other disorders such as heart failure and neurological diseases. Three species of schistosome are responsible for most human infections (Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium). These species are found in different geographical locations, have different vectors, and cause different symptoms. Schistosomes are multicellular parasites that are disseminated as free swimming larvae (cercariae) in ponds, lakes, and rivers by snails. Humans become infected when they stay in contaminated water for a few minutes. The cercariae penetrate the human skin and develop into male or female adult schistosomes within 5 or 6 weeks. These small worms (Fig. 12.1A) can live in the vascular system of their vertebrate host for 2 to 5 years. Schistosomes do not multiply within their vertebrate host. The female worms, however, lay hundreds of eggs per day in the mesenteric or vesical veins of their host. Most of the symptoms associated with these infections are caused by the inflammation that is induced by the immunogenic and toxic substances produced by the eggs. The chronic cellular reaction that develops around the eggs is organised in a granuloma (Von Lichtenberg, 1962; Warren et al., 1967).