Project description:Latent tuberculosis infection (LTBI) relies on a homeostasis of macrophages and Mycobacterium tuberculosis (Mtb). The small heat shock protein, Mtb Hsp16.3 (also known as latency-associated antigen), plays an important role in Mtb persistence within macrophages. However, the mechanism of LTBI remains elusive. The aim of this study was to delineate LTBI-related miRNA expression in U937 macrophages expressing Mtb Hsp16.3 protein. This study intends to explore the potential function of miRNAs in the interaction of macrophages with Mtb Hsp16.3 and provide insights for investigating the role of macrophage homeostasis in LTBI.
Project description:Latent tuberculosis infection (LTBI) relies on a homeostasis of macrophages and Mycobacterium tuberculosis (Mtb). The small heat shock protein, Mtb Hsp16.3 (also known as latency-associated antigen), plays an important role in Mtb persistence within macrophages. However, the mechanism of LTBI remains elusive. The aim of this study was to delineate LTBI-related miRNA expression in U937 macrophages expressing Mtb Hsp16.3 protein. This study intends to explore the potential function of miRNAs in the interaction of macrophages with Mtb Hsp16.3 and provide insights for investigating the role of macrophage homeostasis in LTBI. U937 macrophages were infected with an integrase-deficient Lentivirus vector to transiently express Mtb Hsp16.3, and green fluorescent protein (GFP) as a control. We used a microRNA (miRNA) microarray chip containing more than 1000 probes to identify the significant differentially expressed miRNAs in the infected U937 cells, and employed real-time quantitative polymerase chain reaction (qRT-PCR) for validation. Furthermore, we confirmed these candidate LTBI-related miRNAs in peripheral blood mononuclear cells from subjects with LTBI and in healthy control individuals. Functional annotation prediction of miRNA target genes and pathway enrichment analyses were used to explore the putative links between these miRNAs and LTBI.
Project description:A potent Th1 immune response is critical to the control of tuberculosis. The impact of an additive Th2 response on the course of disease has so far been insufficiently characterized, despite increased morbidity after coinfection with Mycobacterium tuberculosis and Th2 eliciting helminths and possible involvement of Th2 polarization in reactivation of latent tuberculosis. Here, we describe the gene expression profile of murine bone marrow derived macrophages alternatively activated by IL-4 to infection with M. tuberculosis. Comparison of transcriptional profiles of infected IL-4 and IFN-g activated macrophages revealed delayed and partially diminished responses in alternatively activated macrophages, characterized by reduced exposure to nitrosative stress and increased iron availability, respectively, to intracellular bacteria. Alternative activation of host macrophages correlated with elevated expression of the M. tuberculosis iron storage protein bfrB as well as reduced expression of the mycobactin synthesis genes mbtI and mbtJ. The extracellular matrix remodelling enzyme matrix metalloproteinase-12 (MMP-12) was induced in alternatively activated macrophages in vitro, and MMP-12 expressing macrophages were abundant at late, but not early, stages of tuberculosis in murine lungs. Our findings emphasize that alternative activation deprives macrophages of control mechanisms which limit mycobacterial growth in vivo, thus supporting intracellular persistence of M. tuberculosis. Keywords: transcriptome, gene regulation, macrophages, IL-4, IFN-gamma, nitric oxide
Project description:An estimated two billion persons are latently infected with Mycobacterium tuberculosis. The host factors that initiate and maintain this latent state and the mechanisms by which M. tuberculosis survives within latent lesions are compelling but unanswered questions. One such host factor may be nitric oxide (NO), a product of activated macrophages that exhibits antimycobacterial properties. Evidence for the possible significance of NO comes from murine models of tuberculosis showing progressive infection in animals unable to produce the inducible isoform of NO synthase and in animals treated with a NO synthase inhibitor. Here, we show that O2 and low, nontoxic concentrations of NO competitively modulate the expression of a 48-gene regulon, which is expressed in vivo and prepares bacilli for survival during long periods of in vitro dormancy. NO was found to reversibly inhibit aerobic respiration and growth. A heme-containing enzyme, possibly the terminal oxidase in the respiratory pathway, likely senses and integrates NO and O2 levels and signals the regulon. These data lead to a model postulating that, within granulomas, inhibition of respiration by NO production and O2 limitation constrains M. tuberculosis replication rates in persons with latent tuberculosis.
Project description:This SuperSeries is composed of the following subset Series: GSE6209: The global transcriptional profile of Mycobacterium tuberculosis during human macrophages infection GSE7962: Sigma factor E of Mycobacterium tuberculosis controls the expression of bacterial components that modulate macrophages Keywords: SuperSeries Refer to individual Series
Project description:①Background:Tuberculosis is mainly a respiratory tract infection caused by mycobacterium tuberculosis and one of the leading causes of death worldwide. According to the Global Tuberculosis Report in 2021, About a quarter of the world's population is infected with Mycobacterium tuberculosis and China is the second highest burden of TB. Although TB diagnosis and prevention techniques have become more mature, the number of TB cases is still increasing, mainly due to: the prevalence of drug-resistant tuberculosis bacteria, tuberculosis and HIV co-infection, long incubation time of mycobacterium tuberculosis difficult to early diagnosis and so on. Therefore, it is of great significance to study the pathogenesis of mycobacterium tuberculosis infection.②Method: THP-1 cells were treated with 50ng/ml PMA for 24 hours, so that THP-1 cell can be induced into macrophages. After that THP-1 macrophages were infected with mycobacterium tuberculosis H37Rv(MOI=1), which were collected and applied to RNA-sequencing. The constructed sequencing library was sequenced using an Illumina Novaseq 6000 system.
Project description:This project presents a data-independent acquisition mass spectrometry (DIA-MS)–based plasma proteomics dataset generated to identify protein biomarkers associated with recent Mycobacterium tuberculosis (M.tb) infection. The study aimed to characterize proteomic differences among individuals with recently acquired latent tuberculosis infection (LTBI), remotely acquired LTBI, and bacteriologically confirmed active tuberculosis (TB).
Project description:Tuberculosis (TB) is responsible for the majority of mortality and morbidity associated with infectious diseases worldwide. The characterization of exact molecular components of immune response associated with protection against TB may help design more effective therapeutic interventions. In this study, we aimed to characterize the immune signature of memory T cells associated with latent infection with Mycobacterium tuberculosis. Transcriptomic profiling using RNA sequencing was performed on memory CD8 T cells isolated from individuals with latent tuberculosis, as well as from tuberculosis negative healthy controls. Overall, we found specific gene signatures in each cell subset that could successfully discriminate between individuals with latent tuberculosis and healthy controls.
Project description:Tuberculosis (TB) is responsible for the majority of mortality and morbidity associated with infectious diseases worldwide. The characterization of exact molecular components of immune response associated with protection against TB may help design more effective therapeutic interventions. In this study, we aimed to characterize the immune signature of memory T cells associated with latent infection with Mycobacterium tuberculosis. Transcriptomic profiling using RNA sequencing was performed on memory CD4 and CD8 T cells isolated from individuals with latent tuberculosis, as well as from tuberculosis negative healthy controls. Overall, we found specific gene signatures in each cell subset that could successfully discriminate between individuals with latent tuberculosis and healthy controls.
Project description:Tuberculosis (TB) is responsible for the majority of mortality and morbidity associated with infectious diseases worldwide. The characterization of exact molecular components of immune response associated with protection against TB may help design more effective therapeutic interventions. In this study, we aimed to characterize the immune signature of memory T cells associated with latent infection with Mycobacterium tuberculosis. Transcriptomic profiling using RNA sequencing was performed on memory CD4 T cells isolated from individuals with latent tuberculosis, as well as from tuberculosis negative healthy controls. Overall, we found specific gene signatures in each cell subset that could successfully discriminate between individuals with latent tuberculosis and healthy controls.