Project description:In order to investigate the impact of using in vitro techniques to generate single cell suspensions of Mycobacterium tuberculosis (Mtb) on macrophage gene expression, we compared uninfected bone marrow derived macrophages to macrophages infected with Mtb that was prepared using gentle sonication followed by low-speed centrifugation (so/sp) or passage through a 5 µm syringe filter (5µmF).
Project description:The purpose of this study was to identify Mtb- and hsa-encoded miRNAs produced in infected macrophages. RNA from 9 THP-1 samples (3 were uninfected, 3 were infected with Mtb H37Rv for 3 days and 3 were infected with Mtb H37Rv for 6 days) was sequenced and miRNAs were detected.
Project description:Mycobacterium tuberculosis (Mtb) is well adapted to survive in macrophages and usually subverts the bactericidal mechanisms of these professional phagocytes. The adaptation of Mtb to the intracellular life depends on its ability to regulate the expression of its genes. Among the most important bacterial transcription activators are the sigma factors that bind to the RNA polymerase and give it promotor specificity. Sigma factor E (SigE) controls the expression of genes that are essential for Mtb virulence. Analysis of the macrophage transcriptional response indicated that proteins encoded by the sigE regulon are involved in the modulation of the macrophage inflammatory response. We compared the global gene expression of THP1 macrophages infected with H37Rv and SigE to the gene expression profile of uninfected macrophages.
Project description:Mycobacterium tuberculosis (Mtb) is well adapted to survive in macrophages and usually subverts the bactericidal mechanisms of these professional phagocytes. The adaptation of Mtb to the intracellular life depends on its ability to regulate the expression of its genes. Among the most important bacterial transcription activators are the sigma factors that bind to the RNA polymerase and give it promotor specificity. Sigma factor E (SigE) controls the expression of genes that are essential for Mtb virulence. Analysis of the macrophage transcriptional response indicated that proteins encoded by the sigE regulon are involved in the modulation of the macrophage inflammatory response. We compared the global gene expression of mouse bone marrow macrofages infected with H37Rv and SigE to the gene expression profile of the uninfected macrophages.
Project description:Mycobacterium tuberculosis (Mtb) has developed specialized mechanisms to parasitize its host cell, the macrophage. These mechanisms allow it to overcome killing by oxidative burst and persist in the wake of an inflammatory response. Mtb infection in the majority of those exposed is controlled in an asymptomatic form referred to as latent tuberculosis infection (LTBI). HIV is a well-known catalyst of reactivation of LTBI to active TB infection (ATB). Through the use of nonhuman primates (NHPs) co-infected with Mtb and Simian Immunodeficiency Virus (Mtb/SIV), we are able to simulate human progression of TB/AIDS comorbidity. The advantage of NHP models is that they recapitulate the breadth of human TB outcomes, including immune control of infection, and loss of this control due to SIV co-infection. Using macaques infected with Mtb or Mtb/SIV and with different clinical outcomes we attempted to identify signatures between those that progress to active infection after SIV challenge (reactivators) and those that control the infection (non-reactivators).
Project description:Cannabinoid administration before and after simian immunodeficiency virus (SIV)-inoculation ameliorated disease progression and decreased inflammation in male rhesus macaques. Δ9-tetrahydrocannabinol (Δ9-THC) did not increase viral load in brain tissue or produce additive neuropsychological impairment in SIV-infected macaques. To determine if the neuroimmunomodulation of Δ9-THC involved differential microRNA (miR) expression, miR expression in the striatum of uninfected macaques receiving vehicle (VEH) or Δ9-THC (THC) and SIV-infected macaques administered either vehicle (VEH/SIV) or Δ9-THC (THC/SIV) was profiled using next generation deep sequencing.
Project description:In our rabbit model of pulmonary tuberculosis, infection with Mtb HN878, a hyper-virulent W-Beijing strain, results in progressive cavitary disease. However, infection of rabbit lungs with Mtb CDC1551, a hyper-immunogenic strain is effectively controlled overtime, establishing latent Mtb infection. Using these two Mtb strains, we tested the hypothesis that the initial host response in the lungs within hours of infection determines later outcome. The microarray experiments was performed to identify gene expression changes in the Mtb-HN878 or CDC1551- infected rabbit lungs at 3 hours post infection, compared to uninfected naïve rabbit lungs. New Zealand White rabbits were infected with Mtb HN878 or CDC1551 at ~3.5log10. At 3 hours post infection, lung tissue from Mtb-infected and uninfected rabbits were isolated and used for total RNA extraction. Total rabbit lung RNA was used for microarray analysis to determine infection induced changes in host gene expression.
Project description:Primary human monocytes were isolated from four healthy human blood donors. Monocytes were isolated from PBMC buffy coats using plastic adherence for 4 hours. Monocytes were allowed to differentiate into macrophages over a period of 1 week. Macrophages from each of the 4 donors were split into two groups - uninfected and infected with Mycobacterium tuberculosis (Mtb). Cells in the infection group were infected with Mtb for 48 hours at a multiplicity of infection (MOI) of 10. Following incubation, uninfected and infected cells were harvested for RNA. RNA was used for next-generation RNA sequencing. Raw RNA sequencing data was processed using a HISAT2, Stringtie, Ballgown, DESeq2 pipeline. Processed data was used to measure differential expression between uninfected and infected macrophages.
Project description:We used microarrays to detail the global gene expression changes in the ileum of SIV-infected and uninfected macaques following administration of L. plantarum.
Project description:A functional polymorphism responsible for TOLLIP deficiency is associated with increased tuberculosis risk. However, TOLLIP’s role in TB pathogenesis is unknown. Tollip-/- mice developed severe Mycobacterium tuberculosis (Mtb) disease, characterized by macrophage and T cell inflammation from multiple cell populations alongside foam cell formation and lipid accumulation. Tollip-/- alveolar macrophages (AM) selectively accumulated lipid and underwent necrosis in an autonomous manner. Transcriptional and protein analysis analysis of Mtb-infected, Tollip-/- AM demonstrated increased EIF2 signaling, a key regulator of the integrated stress response (ISR) to variable environmental conditions. The ISR, inflammation, and lipid accumulation were linked, as incubation of the Mtb lipid mycolic acid with Mtb-infected Tollip-/- AM led to ISR activation and Mtb replication. Correspondingly, ISRIB, a small-molecule ISR inhibitor, selectively reduced Mtb intracellular carriage in AM and improved Mtb control, overcoming the inflammatory phenotypeinflammation. Targeting the ISR broadly improves Mtb control and immunopathology, offering a promising target for host-directed tuberculosis therapy.
