Project description:Different strains of T. brucei induce different degrees of pathology in infected animals, and TREU927-infected mice display greater splenomegaly and anaemia than 247-infected mice. The analysis of differential host gene expression in infected spleens has allowed the identification of which pathways or processes are crucial in determining the progression of disease, for example IL10, LXR/RXR activation and alternative macrophage activation. We used microarray analysis to examine host gene expression between uninfected and infected mice, and between mice infected with the two trypanosome strains.
Project description:Different strains of T. brucei induce different degrees of pathology in infected animals, and TREU927-infected mice display greater splenomegaly and anaemia than 247-infected mice. The analysis of differential host gene expression in infected spleens has allowed the identification of which pathways or processes are crucial in determining the progression of disease, for example IL10, LXR/RXR activation and alternative macrophage activation. We used microarray analysis to examine host gene expression between uninfected and infected mice, and between mice infected with the two trypanosome strains. Mouse spleens were dissected from infected or uninfected mice 10 days post infection, when the differences in pathology criteria (hepatomegaly, red blood cell numbers, reticulocyte percentage, IL10, IFNg and Il12 levels, and splenomegaly) were the greatest. This allowed a three-way comparison, uninfected vs 247-infected, uninfected vs 927-infected, and 247-infected vs 927-infected, allowing us to analyse genes that are differentially expressed between infected and uninfected spleens, but also crucially allows the differentiation between host gene expression with pathogenic (927) and less pathogenic (247) trypanosome strains.
Project description:Knowledge on the dynamic features of the processes driven by malaria parasites in the spleen, our biggest lymphoid organ, is lacking. We have implemented intravital microscopy and magnetic resonance imaging of the mouse spleen in experimental infections with the Plasmodium yoelii non-lethal (17X) and lethal (17XL) strains. Notably, there was higher parasite accumulation, reduced motility, lost of directionality and different T2 relaxation times only in spleens of mice infected with the 17X strain. Moreover, these differences were associated with the formation of a strain-specific induced spleen tissue barrier, with macrophage-clearance escape, and with cytoadherence of infected reticulocytes to this barrier. This is a novel spleen-immune evasion mechanism in which parasite-induced spleen remodeling and adherence to this organ allow establishment of chronic infections. We performed time-series global transcriptional analyses from spleens of mice infected with the P. yoelii 17X and 17XL strains at days 3, 4, 5, 10% and 50% of parasitemia post-infection, together with non-infected spleens as a reference day 0, using commercially available arrays representing the complete mouse genome (Agilent Whole Mouse Genome G4122A).
Project description:RNA-SEQ analysis of antigen-specific CD8 T cells sorted from murine liver tumors and from the spleens of Listeria-infected mice at different early timepoints following adoptive transfer. We sequenced naive antigen-specific CD8 T cells from spleens for comparison.
Project description:ATAC-SEQ analysis of antigen-specific CD8 T cells sorted from murine liver tumors and from the spleens of Listeria-infected mice at different early timepoints following adoptive transfer. We sequenced naive antigen-specific CD8 T cells from spleens for comparison. We also sorted tumor-infiltrating antigen-specific CD8 T cells that were removed from tumors and parked in tumor-free hosts for 5 days. The overall goal of this study was to determine the earliest chromatin remodeling events in CD8 T cells activated and differentiating in late tumor-bearing hosts or in infected mice and to determine the extent to which tumor-induced chromatin remodeling was "imprinted."
Project description:Malaria is a disease with diverse symptoms depending on host immune status and pathogenicity of Plasmodium parasites. The continuous parasite growth within a host suggests mechanisms of immune evasion and/or inhibition. To identify pathways commonly inhibited by malaria infection, we infected C67BL/6 mice with four Plasmodium yoelii strains causing different disease phenotypes and 24 progeny of a genetic cross. mRNAs from mouse spleens day 1 and/or day 4 post infection (p.i.) were hybridized to a mouse microarray to identify activated or inhibited pathways, upstream regulators, and linkages to parasite genetic loci. Strong interferon responses were observed after infection with N67 strain, whereas initial inhibition and later activation of hematopoiesis pathways were found after infection with 17XNL parasite. Inhibition of pathways such as Th1 activation, dendritic cell (DC) maturation, and NFAT immune regulation were observed in mice infected with all the parasite strains day 4 p.i., suggesting universally inhibited immune pathways. Treatment of infected mice with antibodies against T cell receptors OX40 or CD28 to activate malaria-inhibited pathways enhanced host survival. Controlled activation of these pathways may provide important strategies for better disease management and for developing an effective vaccine.
Project description:Knowledge on the dynamic features of the processes driven by malaria parasites in the spleen, our biggest lymphoid organ, is lacking. We have implemented intravital microscopy and magnetic resonance imaging of the mouse spleen in experimental infections with the Plasmodium yoelii non-lethal (17X) and lethal (17XL) strains. Notably, there was higher parasite accumulation, reduced motility, lost of directionality and different T2 relaxation times only in spleens of mice infected with the 17X strain. Moreover, these differences were associated with the formation of a strain-specific induced spleen tissue barrier, with macrophage-clearance escape, and with cytoadherence of infected reticulocytes to this barrier. This is a novel spleen-immune evasion mechanism in which parasite-induced spleen remodeling and adherence to this organ allow establishment of chronic infections.
Project description:We infected mice with Brucella, took mouse spleens 6 days after infection, isolated and lysed mouse splenocytes for mass spectrometry experiments.
Project description:Transcriptome analysis of peritoneal lavage of mice infected with T. gondii Toxoplasma gondii is the causative agent of toxoplasmosis in human and animals. In mouse model, T. gondii strains can be divided into three groups, including the virulent, intermediately virulent and non-virulent. The clonal Type I, II and III T. gondii strains belong to these three groups respectively. To better understand the basis of virulence phenotypes, we investigated mouse gene expression responses to the infection of different T. gondii strains at day 5 post intraperitoneal inoculation with 500 tachyzoites. The transcriptomes of mouse peritoneal cells showed that 1927, 1573, and 1009 transcripts were altered more than 2 fold by Type I, II and III infections, respectively, and majority of altered transcripts were shared. Overall transcription patterns were similar in Type I and Type II infections and both had greater changes than that of Type III. Quantification of parasite burden in mouse spleens showed that Type I was 1000 times higher than Type II, and Type II was 20 times higher than Type III. Fluorescence activated cell sorting revealed that Type I and II infections had comparable macrophage populations and both were higher than Type III infection. In addition, Type I infection had higher percentage of neutrophils than that of Type II and III. Taken together, these results suggested that there is a common gene expression response to T. gondii infection in mice. This response is further modified by parasite strain specific factors that determine their distinct virulence phenotypes. We analyzed mRNA from female CD1 outbred mice, 6-8 weeks old infected with Type I, II and III T. gondii strains. We used the Affymetrix Mouse Gene 1.0 ST platform. Raw array data was processed by PartekĀ® Genomics SuiteTM software. Three replicates were performed for Type I-GT1 and Type III-CTG and two replicates for Type II- PTG.