Project description:Gene expression analysis of wild-type and STING knock-out mouse bone marrow-derived macrophages (mBMDM) infected with Brucella abortus or transfected with Brucella abortus DNA. Genes whose expression are affected by Brucella abortus in a STING-dependent manner will be identified and signaling pathways regulated by STING will be elucidated.
Project description:In a time course study, we characterized global gene expression profile of B. abortus-infected macrophages from cattle naturally resistant (R) and susceptible (S) to brucellosis. B. abortus infection causes early down-regulation of transcript levels in Mø from R cattle at 4 h p.i. (22 up- and 126 down-regulated genes) which is reversed by 12 h post-infection (31 up- and 25 down-regulated genes), compared to uninfected control. On the other hand, B. abortus-infected S bovine macrophages exhibited a down-regulated expression profile at 4 (45 up- and 65 down-regulated genes) and 12 h p.i. (47 up- and 193 down-regulated genes). The analysis of the results indicates that B. abortus – infected Mø from cattle naturally R and S to brucellosis display different transcriptional profiles. Specific genes and biological processes identified in this study will further help elucidate how different macrophages from resistant and susceptible animals interact with Brucella during the early infectious process. Keywords: Expression profiling by microarray
Project description:We focused on whether transposon mutagenesis in Brucella abortus could induce difference in the trascriptional responses of RAW 264.7 cell infection model compared to the wild strain infected RAW 264.7 cells. The function of genes in Brucella abortus was analyzed through the identified differences in gene expression between RAW 264.7 cell infected with wild and mutant strains.
Project description:We focused on whether transposon mutagenesis in Brucella abortus could induce difference in the trascriptional responses of RAW 264.7 cell infection model compared to the wild strain infected RAW 264.7 cells. The function of genes in Brucella abortus was analyzed through the identified differences in gene expression between RAW 264.7 cell infected with wild and mutant strains. We analyzed altered transcription in RAW 264.7 cells at 0, 6, 12, and 24 h following the infection with 10 MOI of Brucella abortus wild and mutant strains.
Project description:Brucellosis is still a widespread zoonotic disease. Very little is known about the interaction between B. abortus and trophoblastic cells, which is essential for better understanding the pathogenesis of the Brucella-induced placentitis and abortion, a key event for transmission of the disease. The goal of this study was to evaluate the profile of gene expression by bovine trophoblastic cells during infection with B abortus. Explants of chorioallantoic membranes were inoculated with B. abortus strain 2308. Microarray analysis was performed at 4 h after infection, and expression of cytokines and chemokines by trophoblastic cells was assessed by real time RT-PCR at 6 and 12 h after inoculation. In addition, cytokine and chemokine expression was evaluated in placentomes from experimentally infected cows. Expression of pro-inflammatory genes by trophoblastic cells was suppressed at 4 h after inoculation, whereas a significant up-regulation of CXC chemokines, namely CXCL6 (GCP-2) and CXCL8 (IL-8), was observed at 12, but not at 6 h after inoculation. Placentomes of experimentally infected cows had a similar profile of chemokine expression, with upregulation of CXCL6 and CXCL8. Our data indicate that B. abortus modulates the innate immune response by trophoblastic cells, suppressing expression of pro-inflammatory mediators during the early stages of infection that is followed by a delayed and mild expression of pro-inflammatory chemokines, which is similar to the profile of chemokine expression in the placentomes of experimentally infected cows. This trophoblastic response is likely to contribute to the pathogenesis of B. abortus-induced placentitis. Keywords: trophoblast response to Brucella Total RNA used for microarray analysis was obtained from 6 placentas with 12 infected and 12 control explants from each placenta. At 4 h after inoculation, total RNA was isolated from the trophoblastic surface of the explants. Three RNA pools from two placentas each were generated prior to cDNA synthesis.