Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA112061 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Granulomas function in humans during tuberculosis by focusing production of host antimicrobial factors against the causative bacterial agent Mycobacterium tuberculosis to contain infection. We show that mice unable to produce nitric oxide –itself an important antimicrobial molecule- demonstrate functional granulomas in the lung able to control infection after dermal infection. Disease in the lung was activated by administration of neutralising antibody against either TNF-α, which disrupted granuloma integrity, or INF-γ, which resulted in development of caseous necrosis within granulomas reminiscent of active human tuberculosis. In the latter case, the serpin protease inhibitor serpinb3a and its target protease, cathepsin G are highly expressed in cells local to necrotic regions in granulomas and serpinb3a induces necrosis of infected macrophages independently of cathepsin G binding. Therefore a single host protein is capable of inducing necrosis and bacterial growth during intracellular infection.
2010-12-22 | GSE14826 | GEO
Project description:Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is defined by granulomas—immune aggregates that either contain or support bacterial replication. Macrophages, fundamental components of these lesions, are crucial to TB pathogenesis, yet their phenotypic and functional diversity remains incompletely understood. Here, we used single-cell RNA sequencing and immunofluorescence to profile macrophages in lung tissue and granulomas from a nonhuman primate model of early TB. We identified transcriptionally distinct subsets, including embryonic-origin tissue-resident alveolar macrophages and monocyte-derived alveolar and interstitial macrophages, each with distinct spatial localization in granulomas. Tissue-resident alveolar macrophages and a subset undergoing epithelial-to-mesenchymal transition accounted for the highest frequency of Mtb-infected cells. Infected cells exhibited differential expression of immune- and migration-associated genes compared to uninfected counterparts, suggesting Mtb either induces or exploits these pathways as a survival strategy. These findings highlight macrophage heterogeneity as a major driver of differential susceptibility to Mtb and provide insights relevant to future immunomodulatory strategies.
2025-11-30 | GSE296788 | GEO
Project description:Mycobacterial granulomas are categorical manifestations of tuberculosis pathogenesis. They result from an ensemble of immune responses to Mycobacterium tuberculosis infection, but the identities, arrangement, cellular interactions and regulation of the cells that comprise them has thus far been incompletely understood. Using the Mycobacterium marinum-zebrafish model we found that mycobacterial infection induces spp1 expression in macrophages and that spp1 ablation results in granuloma formation defects and reduced survival in adult animals. To determine the impact of mycobacterial infection on the transcriptional response of nascent granuloma macrophages we conducted bulk RNA-seq on flow-sorted infected and uninfected macrophages isolated from infected larvae or uninfected controls.
2025-06-13 | GSE296119 | GEO
Project description:Interferon (IFN)-γ-producing CD8+ T cells are involved in control of Mycobacterium tuberculosis (Mtb) infection, in part by promoting antimicrobial activities of macrophages. Whether Mtb counters these responses, particularly during the hypoxic conditions that arise within granulomas during infection, remains unknown. Using metabolomic, proteomic and genetic approaches, here we show that Mtb induces Rv0884c (SerC), a Mtb phosphoserine aminotransferase, to produce D-serine. This activity increased Mtb pathogenesis in mice but did not directly affect intramacrophage Mtb survival. Instead, D-serine inhibited IFN-γ production by CD8+ T cells, which indirectly reduced the ability of macrophages to restrict Mtb upon coculture. Mechanistically, D-serine interacted with WDR24, a subunit of GATOR2, and inhibited mTORC1 activation in T cells. This decreased T-bet transcription factor expression by CD8+ T cells and reduced IFN-γ production. Our findings suggest a mechanism of mycobacterial metabolic adaptation to hypoxia which leads to amino acid-dependent suppression of adaptive anti-TB immunity.
2024-08-10 | PXD050258 | Pride
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.
2007-09-29 | E-SMDB-4062 | biostudies-arrayexpress
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. The quality controls were biological replicate and technical replicate
2007-08-21 | E-GEOD-8839 | biostudies-arrayexpress
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.
2007-08-22 | GSE8839 | GEO
Project description:Most individuals infected with Mycobacterium tuberculosis can control the infection by forming and maintaining TB granulomas at the local infection foci. However, when the chronic infection (also known as latency) becomes active, the caseous center of TB granuloma enlarges, and it liquefies and cavitates, ultimately releasing bacilli into airway. Deciphering how genes are regulated within TB granulomas will help to understand the granuloma biology. Therefore, we performed genome-wide microarray on caseous human pulmonary TB granulomas and compared with normal lung tissues.
2010-06-02 | GSE20050 | GEO
Project description:Necrotic cell death represents a major pathogenic mechanism of Mycobacterium tuberculosis (Mtb) infection. It is increasingly evident that Mtb induces several types of regulated necrosis but how these are interconnected and linked to the release of pro-inflammatory cytokines remains unknown. Exploiting a clinical cohort of tuberculosis patients, we show here that the number and size of necrotic lesions correlates with IL-1β plasma levels as a strong indicator of inflammasome activation. Our mechanistic studies reveal that Mtb triggers mitochondrial permeability transition (mPT) and subsequently extensive macrophage necrosis which requires activation of the NLRP3 inflammasome. NLRP3 driven mitochondrial damage is dependent on proteolytic activation of the pore forming effector protein gasdermin D (GSDMD) which links two distinct cell death machineries. Intriguingly, GSDMD, but not the membranolytic mycobacterial ESX-1 secretion system is dispensable for IL-1β secretion from Mtb-infected macrophages. Thus, our study dissects a novel mechanism of pathogen induced regulated necrosis by identifying mitochondria as central regulatory hubs capable of delineating cytokine secretion and lytic cell death.
2022-02-17 | PXD029017 | Pride
Project description:Curing tuberculosis (TB) remains challenging due to treatment complexity and high recurrence rates. Through bioinformatic analyses of the immune landscape within clinical non-tuberculous granulomas (NTBG)/tuberculous granulomas (TBG) samples, and peripheral blood from drug-resistant/sensitive, recurrent/non-recurrent TB patients, we identifies suppression of innate immune responses, especially downregulated Toll-like receptor/NF-kappa B pathways in macrophages/dendritic cells and elevated B/T cell negative regulation, contributing to treatment failure and recurrence. Building on these insights, we developed mannose-modified organic semiconducting nano-immunostimulants (manSNI) for precise TB sono-immunotherapy. Under optimized ultrasound condition, manSNI generates massive reactive oxygen species (ROS) to eradicate Mycobacterium tuberculosis (M.tb) within lung granulomas/macrophages, while simultaneously promoting in situ release of M.tb-derived antigens. The released antigens and TLR7 agonist R837 synergistically induce potent innate/adaptive anti-TB immunity and long-lasting immune memory. This granulomas immune landscape-guided sono-immunotherapy strategy demonstrates efficient TB control and relapse/reinfection prevention, which provides a promising direction for customized therapy against high-pathogenic infections.
2025-12-06 | PXD071692 |