Project description:Trypanosoma cruzi is an obligate intracellular protozoan parasite that causes human Chagas’ disease, a leading cause of heart failure in Latin America. Using Affymetrix oligonucleotide arrays we screened phenotypically diverse human cells (foreskin fibroblasts, microvascular endothelial cells and vascular smooth muscle cells) for a common transcriptional response signature to T. cruzi. A common feature was a prominent type I interferon response, indicative of a secondary response to secreted cytokines. Using transwell plates to distinguish cytokine-dependent and -independent gene expression profiles in T. cruzi-infected cells, a core cytokine-independent response was identified in fibroblasts and endothelial cells that featured metabolic and signaling pathways involved in cell proliferation, amino acid catabolism and response to wounding. Significant downregulation of genes involved in mitotic cell cycle and cell division predicted that T. cruzi infection impedes cell cycle progression in the host cell.
Project description:Trypanosoma cruzi is a protozoan parasite and the etiologic agent of Chagas disease, an important public health problem in Latin America. T. cruzi is diploid, almost exclusively asexual, and displays an extraordinarily diverse population structure both genetically and phenotypically. Yet, to date the genotypic diversity of T. cruzi and its relationship, if any, to biological diversity have not been studied at the whole genome level. In this study, we used whole genome oligonucleotide tiling arrays to compare gene content in biologically disparate T. cruzi strains by comparative genomic hybridization (CGH). We observed that T. cruzi strains display widespread and focal copy number variations (CNV) and a substantially greater level of diversity than can be adequately defined by the current genetic typing methods. As expected, CNV were particularly frequent in gene family-rich regions containing mucins and trans-sialidases but were also evident in core genes. Gene groups that showed little variation in copy numbers among the strains tested included those encoding protein kinases and ribosomal proteins, suggesting these loci were less permissive to CNV. Moreover, frequent variation in chromosome copy numbers were observed, and chromosome-specific CNV signatures were shared by genetically divergent T. cruzi strains, suggesting a greater degree of chromosome exchange than previously thought.
Project description:Chagas’ disease, one of the major public health concerns in Latin America, is caused by the haemophlagelated protozoan Trypanosoma cruzi (T. cruzi). In the past few years congenital transmission of T. cruzi has become more important, and partly responsible for the “globalization of Chagas’ disease”. The congenital transmission, although with low rates, represents the main route of transmission in non-endemic countries and endemic countries without vectorial transmission, and represents one third of the new cases each year. Diverse pathogens, including T. cruzi, are able to cross the placental barrier and infect both the placenta and fetus. However, the exact cellular and molecular mechanisms of host-pathogen interaction between T. cruzi and the placenta has been scarcely studied. The use of microarray analysis to determine expression profiles constitutes a powerful tool in order to identify genes and pathways related to the host response to infections. Here, we analyzed the transcriptomic response of human placental chorionic villi explants (HPCVE) challenged with T. cruzi trypomastigotes at low (105) and high (106) concentrations for 2 and 24 hours
Project description:Trypanosoma cruzi is a protozoan parasite and the etiologic agent of Chagas disease, an important public health problem in Latin America. T. cruzi is diploid, almost exclusively asexual, and displays an extraordinarily diverse population structure both genetically and phenotypically. Yet, to date the genotypic diversity of T. cruzi and its relationship, if any, to biological diversity have not been studied at the whole genome level. In this study, we used whole genome oligonucleotide tiling arrays to compare gene content in biologically disparate T. cruzi strains by comparative genomic hybridization (CGH). We observed that T. cruzi strains display widespread and focal copy number variations (CNV) and a substantially greater level of diversity than can be adequately defined by the current genetic typing methods. As expected, CNV were particularly frequent in gene family-rich regions containing mucins and trans-sialidases but were also evident in core genes. Gene groups that showed little variation in copy numbers among the strains tested included those encoding protein kinases and ribosomal proteins, suggesting these loci were less permissive to CNV. Moreover, frequent variation in chromosome copy numbers were observed, and chromosome-specific CNV signatures were shared by genetically divergent T. cruzi strains, suggesting a greater degree of chromosome exchange than previously thought. Genomic DNA samples from 16 T. cruzi strains were compared to genomic DNA from the CL Brener strain by competitive hybridizations on whole genome oligonucleotide tiling arrays.
Project description:Trypanosoma cruzi is the protozoan that causes Chagas disease, an endemic parasitosis in Latin America that has spread around the globe. Recently, a series of studies indicate that the gastrointestinal tract represents an important reservoir for T. cruzi in the chronic phase. It is also known that, during contact between T. cruzi and host cells, there is a release of extracellular vesicles (EVs) that modulates the immune system and enhances the infection, but the dynamics of secretion of host and parasite molecules through these EVs is not understood. In this study, we used two cell lines to simulate the environments found by the parasite in the host: C2C12 cell (myoblast) and Caco-2 cell (intestinal epithelium). We isolated large EVs (LEVs) from the interaction of T. cruzi culture-derived trypomastigotes (TCTs) belonging to two distinct strains (CL Brener, DTU Tc VI and Dm28c DTU Tc I) in contact with C2C12 and Caco-2 cells to 2 hours and after 24 hours of infection. The interaction of the parasite with the host cell induces a switch in the functionality of proteins carried by LEVs and a varied tissue answer. Protein-protein interaction analysis indicates that LEVs carry key proteins for host-pathogen interaction that could participate in the pathogenesis of Chagas Disease.