Project description:Transcriptional response of THP-1 cells infected with Mycobacterium tuberculosis utilizing ‘Active’ Mtb and ‘Dormant’ Mtb infection models at different time points. Analysis of the transcriptomic data deciphered the perturbation of gamut of host cellular pathways that are common and differentially manifested in the ‘Active’ Mtb and ‘Dormant’ Mtb infection models.
Project description:To study the role of WhiB3 in regulating host transcriptome, THP-1 were activated with PMA and infected with Mtb and MtbΔwhiB3, host transcriptome was studied.
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:This study aims to identify the specific miRNA of mycobacterium tuberculosis (M.tb) infected THP-1 by next-generation sequencing, and further to explore the role of miRNA in innate immunity against M.tb infection.Comprehensive analysis of the next-generation sequencing results showed that the expression of miR-99a-5p was significantly lower in the MTB infected THP-1 cells.
Project description:To compare gene expression changes induced by infection with Mycobacterium tuberculosis (Mtb) with changes induced by purified Mtb products, we infected THP-1 cells with Mtb strain H37Rv or treated with purified Mtb products, then performed RNAseq.
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:Tuberculosis (TB) is the deadliest infectious disease worldwide. One obstacle hindering the elimination of TB is our lack of understanding of host-pathogen interactions. Exosomes, naturally loaded with microbial molecules, are circulating markers of TB. Changes in the host protein composition of exosomes from Mycobacterium tuberculosis (Mtb)-infected cells have not been described, can contribute to our understanding of the disease process, and serve as a direct source of biomarkers or as capture targets to enrich for exosomes containing microbial molecules. Here, the protein composition of exosomes from Mtb-infected and uninfected THP-1-derived macrophages was evaluated by tandem-mass-spectrometry and differences in protein abundances were assessed. Our results show that infection with Mtb leads to significant changes in the protein composition of exosomes. Specifically, 41 proteins were significantly more abundant in exosomes from Mtb-infected cells; 63% of these were predicted to be membrane associated. Thus, we used a novel biotinylation strategy to verify protein localization, and confirmed the localization of some of these proteins in the exosomal membrane. Our findings reveal another important scenario where Mtb could be influencing changes in host cells that unveil new features of the host-pathogen interaction and may also be exploited as a source of biomarkers for TB.
Project description:Rationale: Tuberculosis has a devastating impact on global health by claiming nearly 1.4 million lives each year. During infection Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, produces heterogenous populations some of which don’t produce colonies on agar but grow in liquid media and often require supplementation with culture supernatants or recombinant Resuscitation-promoting factor, thus defined as differentially culturable bacilli. Objectives: to evaluate whether exposure to nitric oxide (NO), a well-known host defence molecule, alters mycobacterial growth phenotypes and drives generation of Rpf-dependent differentially culturable bacilli. Methods: a novel NO donor was synthesised and tested against Mtb and Mycobacterium bovis BCG in vitro, followed by growth assays, flow cytometry analysis and assessment of transcriptomic responses. Resuscitation-promoting factor (Rpf) inhibitors were used to characterise the role of Rpf proteins in the reactivation of NO-treated mycobacteria. Mycobacterial phenotypes were also investigated during infection of THP-1 macrophages activated with retinoic acid and vitamin D3. Measurements and Main Results: differentially culturable mycobacteria were generated after exposure to the novel NO donor or during infection of activated THP-1 cells. Resuscitation of these differentially culturable bacilli was largely abolished by specific Rpf inhibitors. Transcriptomic analysis revealed redox-associated stress signatures mediated by SigH and SigF, with significant down-regulation of ribosome and cell wall architecture genes, including rpfA, rpfB and rpfE, and induction of genes involved in response to thiol stress, sulphur metabolism and iron acquisition. Conclusion: Our study provides mechanistic insights into the generation of Rpf-dependent Mtb during tuberculosis and outlines a critical role of NO in this process.
