Project description:Comparative genomic analysis of T. cruzi CLB vs Trypanosoma rangeli (strains SC, Choachí, C23, H14, R1625 and PIT10) and Trypanosoma conorhini
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:Antibody recognition of Trypanosoma cruzi conserved proteins was assessed by evaluating pools of patient IgG samples on microarrays of 400,000 peptides covering these proteins as 15-mers with an overlap of 13 amino acids.
Project description:To investigate the early host response triggered by three different strains of Trypanosoma cruzi at a local infection site, changes in host gene expression were monitored in a murine intradermal infection model using Affymetrix oligonucleotide arrays. Robust induction of IFN-stimulated genes (ISGs) was observed in excised skin 24 hours post-infection where the level of ISG induction was parasite strain-dependent with the least virulent strain triggering a muted IFN response. Infection of mice immunodepleted of IFNγ-producing cells or infection of IFNγ-deficient mice had minimal impact on the IFN response generated in T. cruzi infected mice. In contrast, infection of mice lacking the type I IFN receptor demonstrated that type I IFNs are largely responsible for the IFN response generated at the site of infection. These data highlight type I IFNs as important components of the innate immune response to T. cruzi the site of inoculation and their role in shaping the early transcriptional response to this pathogen. We used microarrays to detail the local host transcriptional response to intradermal T. cruzi infection in WT mice and mice depleted of NK cells, or deficient in IFN-gamma or type I IFN responses. Additionally we compared the local host-transcriptional response generated to infection with 3 different strains of Trypanosoma cruzi (Y, Brazil, and G). Keywords: disease state analysis
Project description:As Trypanosoma cruzi, the etiological agent of Chagas disease, multiplies in the cytoplasm of nucleated host cells, infection with this parasite is highly likely to affect host cells. We performed an exhaustive transcriptome analysis of T. cruzi-infected HeLa cells using an oligonucleotide microarray containing probes for greater than 47,000 human gene transcripts. In comparison with uninfected cells, those infected with T. cruzi showed greater than threefold up-regulation of 41 genes and greater than threefold down-regulation of 23 genes. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) of selected, differentially expressed genes confirmed the microarray data. Many of these up- and down-regulated genes were related to cellular proliferation, including seven up-regulated genes encoding proliferation inhibitors and three down-regulated genes encoding proliferation promoters, strongly suggesting that T. cruzi infection inhibits host cell proliferation, which may allow more time for T. cruzi to replicate and produce its intracellular nests. These findings provide new insight into the molecular mechanisms by which intracellular T. cruzi infection influences the host cell, leading to pathogenicity. Keywords: infection response