Project description:The emergence of multidrug resistant (MDR) Mycobacterium tuberculosis (Mtb) strains, resistant to the frontline anti-tubercular drugs rifampicin and isoniazid, forces treatment with less effective and toxic second-line drugs and stands to derail TB control efforts. However, the immune response to MDR Mtb infection remains poorly understood. Here, we determined the RNA transcriptional profile of in vitro generated macrophages to infection with either drug susceptible Mtb HN878 or MDR Mtb W_7642 infection.
Project description:We investigated transcriptional responses of different lung macrophage lineages during M.tuberculosis infection by RNAseq. Our data revealed that different lineages of macrophages respond differentially to M.Tuberculosis infection.
Project description:Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), latently infects one quarter of the world’s population. The rise of multidrug resistant (MDR) Mtb infections worldwide presents a significant obstacle to curb TB globally. While human studies report dysregulated immune responses in MDR TB patients, there is a lack of clear understanding of the host-pathogen interactions following MDR Mtb infection. We recently showed that Mtb carrying a rifampicin drug resistance (RDR)-conferring single nucleotide polymorphism in the RNA polymerase-B gene (Mtb rpoB-H445Y) can modulate host macrophage metabolic reprogramming by production of Type I IFNs. Here, using a mouse model, we have characterized the host immune response in vivo following RDR Mtb infection. We show that despite establishment of Mtb infection in the lung and dissemination to the peripheral organs, lung myeloid and lymphoid immune responses to RDR Mtb is suppressed through a Type I IFN-dependent mechanism. These results coincide with a muted responses in the bone marrow hematopoietic stem and progenitor cells (HSPCs) and progenitors following RDR Mtb infection. These results suggest that host directed therapeutics and vaccines for drug resistant TB may need to be target specific host immune pathways for protection.
Project description:We examined the microRNA profiles of THP-1 macrophages upon the MTB infection of (1) Beijing/W and non-Beijing/W clinical strains, and (2) susceptible and multidrug-resistant (MDR-) MTB strains. THP-1 cells were induced differentiation into a macrophage phenotype. Then cells were infected with three MDR (INHR, RIFR) Beijing/W, three sensitive (INHS, RIFS) Beijing/W, three MDR(INHR, RIFR) non-Beijing/W, and three sensitive (INHS, RIFS) non-Beijing/W strains. Total RNA were extracted and transfered into cDNA for miRNA profile analysis. Non-infected cells were used as control.
Project description:Polarization of macrophages to M1 or M2 cells is important for mounting responses against bacterial and helminth infection respectively. Jumonji domain containing 3 (JMJD3), a histone 3 K27 demethylase, has been implicated in the activation of macrophages. Here we show that JMJD3 is essential for M2 macrophage polarization to helminth infection and chitin, though JMJD3 is dispensable for M1 responses. Furthermore, Jmjd3 is critical for proper bone marrow macrophage differentiation in a demethylase activity-dependent manner. Jmjd3 deficiency affected trimethylation of H3K27 in only a limited numbers of genes. Among them, we identified Irf4 as the target transcription factor critical for controlling M2 macrophage polarization. Collectively, these results show that JMJD3-mediated H3K27 demethylation is critical for regulating M2 macrophage development leading to anti-helminth host responses. This SuperSeries is composed of the SubSeries listed below.
Project description:Background: Tuberculosis (TB) remains a major public health problem, especially in developing countries, with 1.5 million deaths annually worldwide. Macrophages (Mφs) are central to TB pathogenesis. Mφs play a key role in the outcome of the infection. More importantly, Mφs are the primary cell target of MTB, which has developed different strategies to multiply inside the Mφ phagosome. Here we aim to compare the transcriptome of Mycobacterium tuberculosis (MTB)-infected Mφs with that of cells stimulated with heat-killed MTB. Results: Here, we used live and heat-inactivated MTB to examine the impact of infection on the human macrophage response. Gene expression profiling has revealed about 3,259 genes differentially expressed in macrophages incubated with heat-inactivated MTB and 4,179 genes differentially expressed with live MTB. We found that the response to live and heat-inactivated MTB was strongly correlated (r>0.78). Conclusions: Our results show that macrophages respond in a similar manner to live and heat-inactivated MTB. We also identified some genes differentially expressed only in one condition.
Project description:The aquatic orthomyxovirus infectious salmon anemia virus (ISAV) is an important pathogen for salmonid aquaculture, however little is known about protective and pathological host responses to infection. We have investigated intracellular responses during cytopathic ISAV infection in the macrophage-like Atlantic salmon kidney (ASK) cell line by microarray analysis (1.8K SFA2.0 immunochip) and a functional assay for glutathione. Gene transcription changed rapidly and consistently with time and with minor differences between two virus isolates. While several pro-inflammatory and antiviral immune genes were induced, genes involved in cell signaling and integrity were down-regulated, suggesting isolation of infected cells from cell-to-cell interaction and responses to external signals. Differential expression of genes regulating cell cycle and apoptosis implied opposite cues from host cell and virus. This was in pace with massive down-regulation of genes involved in biosynthesis and processing of nucleotides and nucleic acids. Significant down-regulation of several genes involved in metabolism of reactive oxygen species suggested increased oxidative stress, which was confirmed by a functional assay showing reduced levels of glutathione during infection. Testing of expression data against a microarray database containing diverse experiments revealed candidate marker genes for ISAV infection. Our findings provide novel insight into cellular host responses and determinants for acute cytopathic ISAV infection. Keywords: Infectious salmon anemia virus (ISAV); Host response; Molecular pathology; Microarray; Macrophage; Oxidative stress ASK cells infected with ISAV isolate 2 and 4 and mock-infected were cultured in triplicates and total RNA pooled from each at the following time-points post-infection; 1, 3 and 5 days. For microarray analysis, single-slide hybridisation was applied between infected RNA (Cy5 labelled) and control RNA (Cy3 labelled) for each time-point. Results were verified by real-time qPCR.
Project description:The lung host immune responses following M.tuberculosis infection in the mouse model of tuberculosis were assayed by studying the gene expression profiles at day 0, day 12, 15 and 21 post infection Mice were infected with M.tuberculosis via the aerosol route and the host gene induction during early immune response studied
Project description:To gain insight into the alterations of gene expression profile in the course of non-mutationally acquired resistance, we performed RNA-seq comparing MDR persister cells to MDR cancer cells.