Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Phagosomal RNA sensing through TLR8 controls susceptibility to tuberculosis

ABSTRACT: Genetic determinants of susceptibility to Mycobacterium tuberculosis (Mtb) remain poorly understood but could provide insights into critical pathways involved in infection, informing host-directed therapies and enabling risk stratification at individual and population levels. Through a genome-wide forward genetic screen, we identify the Toll-like Receptor 8 (TLR8), as a key regulator of intracellular killing of Mtb. Pharmacological TLR8 activation enhances killing of phylogenetically diverse clinical isolates of drug-susceptible and multidrug-resistant Mtb by macrophages and during in vivo infection in mice. TLR8 is activated by phagosomal mycobacterial RNA released by extracellular membrane vesicles, and enhances xenophagy-dependent Mtb killing. We find that the TLR8 variant, M1V, common in far eastern populations, enhances intracellular killing of Mtb through preferential signal-dependent trafficking to phagosomes. TLR8 signalling may therefore both regulate susceptibility to tuberculosis and provide novel drug targets.

ORGANISM(S): Mycobacterium tuberculosis

PROVIDER: GSE288494 | GEO | 2025/02/05

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other
	GSE288494_RAW.tar	Raw
	filelist.txt	Txt

Items per page:

1 - 3 of 3

Similar Datasets

RNA Sequencing of intra-phagosomal Mtb populations

Project description:Heterogeneity of host cells as well as bacteria residing within them has been known to induce drug tolerance in pathogens. In Mycobacterium tuberculosis, particularly, drug tolerance within host is a major hurdle in the path to attain a sterlising cure. Reports have shown how residence of Mtb within macrophages makes the pathogen refractory to anti-TB therapy. However, the mechanisms responsible for induction of tolerance to antibiotics, particularly in resting macrophages where Mtb continues to actively replicate, is yet to be deciphered. Reports have suggested that heterogeneity induced in Mtb by cues sensed in the host environment could be a contributing factor to drug tolerance. With regard to this, differences in redox physiology of intra-macrophage Mtb (mid-point potential of the major cytosolic redox buffer in Mtb, mycothiol- EMSH) have been shown to play a role in influencing antibiotic-mediated killing. In this study, we have attempted to analyse the trascriptomic profiles of individual redox sub-populations of Mtb from within macrophages- viz., the EMSH-reduced bacteria with mid-point potential ranging between -285 and -310 mV, shown to be most refractory to killing by front-line anti-TB antibiotics inside macrophages, as well as EMSH-basal bacteria with mid-point potential ranging between -270 and -280 mV, with a much higher degree of antibiotic susceptibility within macrophages. Analysing gene expression level differences between these bacterial sub-populations would help in providing a mechanistic understanding of drug tolerance in Mtb, bred from phenotypic heterogeneity in the pathogen.

2019-09-13 | GSE123267 | GEO

RNA Sequencing of intra-phagosomal Mtb populations

Project description:RNA Sequencing of intra-phagosomal Mtb populations

| PRJNA507986 | ENA

Phagosomal RNA sensing through TLR8 controls susceptibility to tuberculosis

Project description:RNA released from Mycobacterium tuberculosis in the macrophage phagosome is sensed by the pattern recognition receptor TLR8 controlling host susceptibility to tuberculosis and revealing a druggable pathway for host-directed therapy

| PRJEB62758 | ENA

USP8 coordinates ESCRT-mediated membrane repair, xenophagy, and oxidative stress responses during Mycobacterium tuberculosis infection

Project description:We show that USP8 colocalizes with intracellular Mtb, recognizes phagosomal membrane damage, and is required for ESCRT-dependent membrane repair. Furthermore, USP8 regulates the NRF2-dependent antioxidant signature. Taken together, our study shows a central role of USP8 in promoting intracellular growth of Mtb by coordinating phagosomal membrane repair, ubiquitin-driven selective autophagy, and the oxidative stress response.

2024-08-07 | GSE240372 | GEO

Complement C5a impairs phagosomal maturation in the neutrophil through phosphoproteomic remodelling.

Project description:Critical illness is characterised by organ failure, dysregulated immune activation and frequent secondary infections. Unbridled complement activation in these patients exposes immune cells to high levels of the anaphylotoxin, C5a. C5a suppresses antimicrobial functions of key immune cells, in particular the neutrophil, and this suppression is associated with poorer outcomes amongst critically ill adults. The intracellular signalling pathways which mediate C5a-induced neutrophil dysfunction are incompletely understood. Healthy donor peripheral blood neutrophils exposed to purified C5a demonstrated a prolonged defect in phagocytosis of the common nosocomial pathogen Staphylococcus aureus which persisted for 7 hours after exposure. Phosphoproteomic profiling of 2712 unique phosphoproteins identified persistent C5a signalling at 1 hour, and selective impairment of phagosomal protein phosphorylation on exposure to S. aureus. Notable proteins included early endosomal marker ZFYVE16 and V-ATPase proton channel component ATPV1G1. A multi-function assay of bacterial ingestion and phagosomal acidification demonstrated C5a-induced impairment of phagosomal acidification in a whole blood model of Staphylococcal bacteraemia which was recapitulated in neutrophils from critically ill patients. Examination of the C5a-impaired protein phosphorylation indicated a role for the phosphatidylinositol 3-kinase VPS34 in phagosomal maturation. Inhibition of VPS34 impaired neutrophil phagosomal acidification, late bacterial ingestion and killing of S. aureus in whole blood. This study provides a deep phosphoproteomic assessment of human neutrophil signalling in response to S. aureus, and demonstrates how some of these pathways are disrupted by exposure to C5a, identifying a defect in phagosomal maturation and providing new information on mechanisms of immune failure in critical illness.

2020-08-06 | PXD017092 | Pride

Proteomic analysis of the secretome of a esxaA mutant Mycobacterium tuberculosis strain

Project description:Extracellular Mycobacterium tuberculosis (Mtb) aggregates can evade phagocytosis and intracellular host-cell defenses by inducing macrophage killing. We showed that Mtb aggregates require a functional ESX-1 type VII secretion system to induce cell death upon contact with macrophages. We used quantitative proteomics to compare the secretome of a esxA mutant strain with the wild type reference to identify secreted bacteria factors involved in macrophage death induction.

2023-03-16 | PXD035082 | Pride

Proteomic analysis of the secretome of selected Mycobacterium tuberculosis Erdman strains

Project description:Extracellular Mycobacterium tuberculosis (Mtb) aggregates can evade phagocytosis and intracellular host-cell defenses by inducing macrophage killing. We showed that Mtb aggregates require a functional ESX-1 type VII secretion system and production of the surface-exposed lipid phthiocerol dimycocerosate (PDIM) to induce cell death upon contact with macrophages. We used quantitative proteomics to compare the secretome of a panel of Mtb mutant strains that induce or do not induce macrophage death and identified secreted bacteria factors involved in macrophage death induction.

2023-03-16 | PXD035080 | Pride

Treatment of human monocytes with TLR7 or TLR8 agonists

Project description:Goal was to detect differences in response to TLR7 versus TLR8 agonists in human monocytes from healthy donors 3 deidentified donors from the Red Cross, monocytes from each donor incubated overnight with either vehicle, TLR7 agonist or TLR8 agonist

2014-12-24 | E-GEOD-64480 | biostudies-arrayexpress

Bacterial RNA sensing by TLR8 requires RNase 6 processing and is inhibited by RNA 2’O-methylation

Project description:Mechanistic studies have revealed that TLR8 senses single-stranded RNA (ssRNA) fragments, processed via synergistic cleavage by ribonucleases (RNase) T2 and RNase A family members. Processing by these RNases releases uridines and purine-terminated residues resulting in TLR8 activation. Monocytes show high expression of RNase 6, yet this RNase has not been analyzed for its physiological contribution to recognition of bacterial RNA by TLR8. Herein, we characterized molecular RNase 6 cleavage mechanisms. BLaER1 RNASE6-/- cells showed a dampened TLR8-dependent response upon stimulation with isolated bacterial RNA (bRNA) but also upon infection with live whole bacteria. Pretreatment of bacterial RNA with recombinant RNase 6 generated fragments that induced stimulation in RNASE6 knockout cells. 2’O-RNA methyl modification, when introduced at the first uridine in the UA dinucleotide, impaired upstream processing by RNase 6 and dampened TLR8 stimulation. In summary, this data shows that RNase 6 plays a critical role in the processing of bacterial RNA by generating uridine-terminated breakdown products that ultimately activate TLR8.

2024-09-12 | PXD053881 | Pride

Mycobacterium tuberculosis cording in lymphatic endothelial cells (hLEC)

Project description:Mycobacterium tuberculosis (Mtb) displayed cording phenotypes during intracellular infection. RNA-Seq was used to identify transcriptional programmes expressed by hLEC that actviates pathways relating to cellular pro-survival and cyosolic surveillance of intracellular Mtb. Mtb cording was found to be a mechanism to evade xenophagy in the cytosol of endothelial cells.

2020-06-04 | GSE110564 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data