Impact of Trypanosoma vivax infections on blood brain barrier crossing / disruption in murine systems

• Grant number: 19/20708-4
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2019
• End date: October 31, 2021
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Paola Marcella Camargo Minoprio
• Grantee: Ana Paula Pessoa Vilela
• Host Institution: Plataforma Científica Pasteur. Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/27131-9 - Integrated strategy for the study of infectious agents causing emerging and/or neglected diseases transmitted by vectors of global impact, AP.TEM

Abstract

To better study T. vivax infections in well-established experimental models, the state-of-the-art in vitro, in vivo and ex vivo imaging tools that were available was revisited by our group and adapted to trypanosomatids generating new and more powerful essential tools for imaging systems (Goyard et al., 2013; Rouault et al., 2016; Dias de Melo et al., 2017). These efforts allow us today to quantify in real time the particularities, abundance and magnitude of trypanosomal infections, to reveal original data related to the development of the pathology, thus opening new research and innovation opportunities. Our preliminary results described the development of a reference model for T. vivax, especially due to the high virulence of the mouse and the parasite's difficulty to grow in axenic cultures. However, to study animal trypanosomosis, Nagana, and to characterize some of the major actors in T. vivax immunopathology, our laboratory has developed the complex T. vivax axenic cultures of an African strain and today dominates the process of parasitic differentiation in in vitro infectious forms (D'Archivio et al., 2011). Reproducible infections were obtained in mice of several strains, which presented parasitological, histological and pathological parameters very similar to those observed in the field, characteristic of cattle trypanosomosis - severe acute anemia, thrombocytopenia and a significant reduction of B lymphocytes after infection (Chamond et al. (2010; Blom-Potar et al., 2010). The in vitro cultivated T. vivax stages allowed the laboratory to construct the first specific expression vectors, which led us to develop reverse genetics for this parasite (D'Archivio et al., 2011).Thus, mastery of axenic cultures was useful for establishing and optimizing parasite transfections and selecting stable mutants that continue metacyclogenesis while maintaining virulence for immunocompetent mice. The region containing the T. vivax ribosomal promoter was inserted into the plasmid to improve expression of the luciferase reporter gene transgene and to allow integration of the vector into the genome. With these tools, the group analyzed the evolution of the infectious process and the distribution of parasites in mouse tissues. The results corroborated the use of real-time biophotonic analysis to study and monitor the infectious process in vivo. Through these experiments, we could suggest that the blood-brain barrier (BBB) is crossed by trypanosomes in the later stages of infection (D'Archivio et al. 2013). T. vivax, in fact, penetrate the brain parenchyma shortly before the death of the animals. Goals: To design the T.vivax brain impairment process and the functional / lethal consequences of the infection process, especially the main histopathological lesions of the brain, forming a base of studies focused on neuroinflammation and the breakdown of the blood-brain barrier. The project will serve as the basis for interfacing with other subprojects of a thematic study involving infections with infectious Zika virus clones, modified by reporter genes for analysis of the infectious process in vitro and in vivo by 2D and 3D imaging.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CUNHA, MARIELTON DOS PASSOS; VILELA, ANA PAULA PESSOA; MOLINA, CAMILA VIEIRA; ACUNA, STEPHANIE MAIA; MUXEL, SANDRA MARCIA; BARROSO, VINICIUS DE MORAIS; BARONI, SABRINA; GOMES DE OLIVEIRA, LILIAN; ANGELO, YAN DE SOUZA; PERON, JEAN PIERRE SCHATZMANN; et al. Atypical Prolonged Viral Shedding With Intra-Host SARS-CoV-2 Evolution in a Mildly Affected Symptomatic Patient. FRONTIERS IN MEDICINE, v. 8, NOV 26 2021. (19/20708-4, 18/11612-0, 17/27131-9, 19/24518-5, 17/23519-2, 20/01487-4)