Project description:Background:; Yersinia outer protein (Yop) H is a secreted virulence factor of Yersinia enterocolitica which inhibits phagocytosis of Y. enterocolitica and promotes virulence of Y. enterocolitica (Ye) in mice. The aim of this study was to address whether and how YopH affects the innate immune response against Ye in mice. Results:; For this purpose mice were infected with wild type Ye (pYV+) or a YopH-deficient Ye mutant strain (DyopH). CD11b+ cells were isolated from infected spleen and subjected to gene expression analysis using microarrays. Despite attenuation of DyopH in vivo, by variation of infection doses we were able to achieve conditions that allow comparison of gene expression in pYV+ and DyopH infections at either comparable infection courses or splenic bacterial burden. Gene expression analysis provided evidence that expression levels of several immune response genes including IFN-g and IL-6 are high after pYV+ infection but low after sublethal DyopH infection. In line with these findings, infection of IFN-gR-/- and IL-6-/- mice with pYV+ or DyopH revealed that these cytokines are dispensable for control of DyopH, but not pYV+ infection. Consistently, in bacteria killing assays with BMM in vitro, stimulation of BMM with IFN-g is required for killing of pYV+ but not DyopH. Conclusion:; In conclusion, this data suggest that IFN-g counteracts YopH-mediated virulence mechanisms of Ye which in Ye wild type infection contribute to evasion of the innate immune response including killing by macrophages. Experiment Overall Design: In this study microarray analyses were performed to define differences in gene expression of cells associated with innate immune response (CD11b+ cells) after infection of mice with a sublethal and lethal infection with wildtype Yersinia enterocolitica compared to uninfected mice. In addition, we wanted to investigate whether differences in gene expression can be defined which are due to the virulence factor YopH. Moroeover, we were interested whether gene expression pattern of sublethal and lethal infected mice are different. Allover all five samples were compared. Number of replicates 1.
Project description:Background: Yersinia outer protein (Yop) H is a secreted virulence factor of Yersinia enterocolitica which inhibits phagocytosis of Y. enterocolitica and promotes virulence of Y. enterocolitica (Ye) in mice. The aim of this study was to address whether and how YopH affects the innate immune response against Ye in mice. Results: For this purpose mice were infected with wild type Ye (pYV+) or a YopH-deficient Ye mutant strain (DyopH). CD11b+ cells were isolated from infected spleen and subjected to gene expression analysis using microarrays. Despite attenuation of DyopH in vivo, by variation of infection doses we were able to achieve conditions that allow comparison of gene expression in pYV+ and DyopH infections at either comparable infection courses or splenic bacterial burden. Gene expression analysis provided evidence that expression levels of several immune response genes including IFN-g and IL-6 are high after pYV+ infection but low after sublethal DyopH infection. In line with these findings, infection of IFN-gR-/- and IL-6-/- mice with pYV+ or DyopH revealed that these cytokines are dispensable for control of DyopH, but not pYV+ infection. Consistently, in bacteria killing assays with BMM in vitro, stimulation of BMM with IFN-g is required for killing of pYV+ but not DyopH. Conclusion: In conclusion, this data suggest that IFN-g counteracts YopH-mediated virulence mechanisms of Ye which in Ye wild type infection contribute to evasion of the innate immune response including killing by macrophages. Keywords: Comparison of gene expression due to bacterial virulence factors
Project description:This model simulates the colonization of the mouse gut with different strains of Yersinia enterocolitica. Thereby it takes the host-immune repsone into account. The parameters are calibrated based on experimentally obtained data (faces of different mice).
Project description:Orogastral infection of mice with Yersinia enterocolitical leads to HIF-1 alpha activation.To elucidate whether this HIF-1 alpha activation also results in a HIF-1 dependent gene programming, the transcriptomes from Peyers Patches of uninfected and Yersinia enterocolitica infected mice were analyzed by means of of microarray analyses using Affymetrix GeneChip probe arrays (MG-U74Av2). In total, 288 genes were differentially regulated three day after infection in PP compared with the expression of uninfected control mice. Of these 288 genes, 217 were found to be differentially upregulated and from these, 14 genes ( 6.5% of all upregulated genes) are well described to be regulated via HIF-1. These data indicate that orogatral infection with Y. enterocolitica results in HIF-1 dependent gene programmning Keywords: Time course
Project description:Orogastral infection of mice with Yersinia enterocolitical leads to HIF-1 alpha activation.To elucidate whether this HIF-1 alpha activation also results in a HIF-1 dependent gene programming, the transcriptomes from Peyers Patches of uninfected and Yersinia enterocolitica infected mice were analyzed by means of of microarray analyses using Affymetrix GeneChip probe arrays (MG-U74Av2). In total, 288 genes were differentially regulated three day after infection in PP compared with the expression of uninfected control mice. Of these 288 genes, 217 were found to be differentially upregulated and from these, 14 genes ( 6.5% of all upregulated genes) are well described to be regulated via HIF-1. These data indicate that orogatral infection with Y. enterocolitica results in HIF-1 dependent gene programmning Experiment Overall Design: Per group five C57BL/6 mice were infected orogastrally with 500 Million Yersinia enterocolitica. 1 and 3 days after infection, Peyers Patches were removed and total RNA was prepared. In parallel, RNA was isolated from uninfected mice. The generation of fragmented cRNA was performed following the manufacturers instructions and used for hybridization onto GeneChip arrays MG-U74Avs2. Analysis of microarray data was performed using the Affymetrix Microarray Suite 5.0, Affymetrix Mining Tool 3.0. A median signal log2 ratio (SLR) grater than 1.5 or less than -1.5 was considered a significant change.
Project description:Enteropathogenic Yersinia enterocolitica and Yersinia pseudotuberculosis share many traits in terms of infections they cause, but their epidemiology and ecology seem to differ in many ways. Pigs are the only known reservoir for Y. enterocolitica 4/O:3 strains while Y. pseudotuberculosis strains have been isolated from variety of sources including fresh vegetables and wild animals. A comparative genomic hybridization (CGH) analysis with a DNA microarray based on three Yersinia enterocolitica and four Yersinia pseudotuberculosis genomes was conducted to shed light on genomic differences between the enteropathogenic Yersinia. In total 99 strains isolated from various sources were hybridized and analyzed.
Project description:RNA-sequencing was preformed from RNA isolated from bacteria infected with the bacteriophage. In order to reveal the phage-host interactions between φR1-37 and Yersinia enterocolitica throughout the phage infection cycle, both the transcriptomes were scrutinized during all the stages of infection.
Project description:The purpose of our study was to fill this knowledge gap and to characterize the epithelial cell response to Yersinia enterocolitica infection by label-free proteomic quantification.
Project description:Pathogenic bacteria Yersinia enterocolitica injects virulence plasmid-encoded effectors through the type three secretion system into macrophages to modulate gene expression. Here we analyzed the effect on gene expression in primary human macrophages of Y. enterocolitica strains lacking effector YopP (1.5 h infection) or effectors YopP and YopM (1.5 h or 6 h infection) simultaneously using RNA-seq. This is part of a larger sequencing experiment for which other samples can be found in EMBL-EBI (www.ebi.ac.uk/arrayexpress) under accession number E-MTAB-10473 and European Nucleotide Archive (ENA) at http://www.ebi.ac.uk/ena/data/view/PRJEB10086.