TLR4 signaling and macrophage inflammatory responses are dampened by GIV/Girdin
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA644556 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR12162971.fastq.gz | Fastqsanger.gz | |||
| SRR12162972.fastq.gz | Fastqsanger.gz | |||
| SRR12162973.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 3 of 3 |
Similar Datasets
Project description:Sensing of pathogens by Toll-like receptor 4 (TLR4) induces an inflammatory response; controlled responses confer immunity but uncontrolled responses cause harm. Here we define how a multi-modular scaffold, GIV (a.k.a Girdin) titrates such inflammatory response in macrophages. Upon challenge with microbe-derived lipopolysaccharides (LPS, a ligand for TLR4), macrophages with GIV mount a more tolerant (hypo-reactive) transcriptional response and suppress pro-inflammatory cytokines and signaling pathways (i.e., NFkB and CREB) downstream of TLR4 compared to their GIV-depleted counterparts.
2020-07-08 | GSE153924 | GEO
Project description:Sensing of pathogens by Toll-like receptor 4 (TLR4) induces an inflammatory response; controlled responses confer immunity but uncontrolled responses cause harm. Here we define how a multimodular scaffold, GIV (a.k.a. Girdin), titrates such inflammatory response in macrophages. Upon challenge with either live microbes or microbe-derived lipopolysaccharides (a ligand for TLR4), macrophages with GIV mount a more tolerant (hypo-reactive) transcriptional response and suppress proinflammatory cytokines and signaling pathways (i.e., NFkB and CREB) downstream of TLR4 compared to their GIV-depleted counterparts. Myeloid-specific gene-depletion studies confirmed that the presence of GIV ameliorates dextran sodium sulfate-induced colitis and sepsis-induced death. The antiinflammatory actions of GIV are mediated via its C-terminally located TIR-like BB-loop (TILL) motif which binds the cytoplasmic TIR modules of TLR4 in a manner that precludes receptor dimerization; such dimerization is a prerequisite for proinflammatory signaling. Binding of GIV's TILL motif to TIR modules inhibits proinflammatory signaling via other TLRs, suggesting a convergent paradigm for fine-tuning macrophage inflammatory responses.
| S-EPMC7604444 | biostudies-literature
Project description:In sepsis, acute lung injury (ALI) is a severe complication and a leading cause of death, involving complex mechanisms that include cellular and molecular interactions between immune and lung parenchymal cells. In recent decades, the role of Toll-like receptor 4 (TLR4) in mediating infection-induced inflammation has been extensively studied. However, how TLR4 facilitates interactions between innate immune cells and lung parenchymal cells in sepsis remains to be fully understood. This study aims to explore the role of TLR4 in regulating macrophage immunity and metabolism in greater depth. It also seeks to reveal how changes in these processes affect the interaction between macrophages and both pulmonary endothelial cells (ECs) and lymphatic endothelial cells (LECs). Using TLR4 knockout mice and the combined approaches of single-cell RNA sequencing and experimental validation, we demonstrate that in sepsis, TLR4-deficient macrophages upregulate Abca1, enhance cholesterol efflux, and reduce glycolysis, promoting M2 polarization and attenuating inflammation. These metabolic and phenotypic shifts significantly affect their interactions with pulmonary ECs and LECs. Mechanistically, we uncovered that TLR4 operates through multiple pathways in endothelial dysfunction: macrophage TLR4 mediates inflammatory damage to ECs/LECs, while endothelial TLR4 both directly sensitizes cells to lipopolysaccharide-induced injury and determines their susceptibility to macrophage-derived inflammatory signals. These findings reveal the complex role of TLR4 in orchestrating both immune-mediated and direct endothelial responses during sepsis-induced ALI, supporting that targeting TLR4 on multiple cell populations may present an effective therapeutic strategy.
2025-03-04 | GSE287641 | GEO
Project description:Interferon (IFN)γ and interleukin (IL)-4 are central regulators of T helper 1 (Th1) and T helper 2 (Th2) immune responses, respectively. Both cytokines have a major impact on macrophage phenotypes: IFNγ–priming and subsequent TLR4 activation induces so called classically activated macrophages that are characterized by pronounced pro-inflammatory responses, whereas IL-4–treated macrophages, commonly called alternatively activated, are known to develop enhanced capacity for endocytosis, antigen presentation, and tissue repair and are generally considered anti-inflammatory. Considering IL-4 as priming rather than activating stimulus, we now compared the TLR4–dependent global gene activation program in IFNγ– versus IL-4–pretreated mouse macrophages, which has rarely been studied so far. Although both cytokines frequently induced opposing effects on gene transcription, the subsequent activation of bone marrow-derived macrophages by lipopolysaccharide (LPS) produced a strong, priming dependent pro-inflammatory response in both macrophage types. For example, the production of key pro-inflammatory cytokines IL-6 and IL-12 was significantly higher in IL-4– versus IFNγ–primed macrophages and several cytokine genes, including Il19, Ccl17, Ccl22, Ccl24 and Cxcl5, were preferentially induced in alternatively primed and LPS activated mouse macrophages. In a subset of genes, including IL12a, IFNγ priming was actually found to suppress LPS–induced gene expression in a Stat1–dependent manner. Our data suggest that IL-4–priming is not per se anti-inflammatory but generates a macrophage that is “tissue protective” but still capable of mounting a strong inflammatory response after TLR4–dependent activation. Keywords: Gene expression profiling Gene expression was investigated in mouse bone marrow-derived macrophages (BMM). On day 7, BMM were stimulated with either IL-4 or IFNγ overnight (18h in total). LPS treatment was performed in primed and unprimed macrophages 4 h prior to harvesting. At least three independent experiments were performed for each condition.
2010-10-01 | E-GEOD-21895 | biostudies-arrayexpress
Project description:The NFκB family of transcription factors is a major regulator of the innate immune responses, and its dysregulation has been linked to several inflammatory diseases. In this study we focused on bone marrow derived macrophages from the recently described p65-DsRed/IκBα-eGFP transgenic strain, in which a human copy of RelA (p65) was introduced into the mouse genome. Confocal imaging analysis showed that the human RelA is expressed these cells and can translocate to the nucleus upon Toll-like receptor 4 activation (TLR4). RNA sequencing analysis of polysaccharide-stimulated macrophage cultures, revealed that the extra copy of human RelA impacts on gene transcription, affecting both NFκB and non-NFκB target genes, including immediate-early and late response NFκB target genes, such as Fos and Cxcl10, respectively. In validation experiments on NFB targets we observed reduced mRNA levels, but similar expression kinetic profile of the transgenic cells compared to the wild type. Enrichment pathway analysis based on the differentially regulated genes revealed that interferon and cytokine signaling, are affected downstream TLR4. These immune response pathways were also affected when the macrophages were treated with tumor necrosis factor. The impact of genetic manipulation on cell-specific functions is particularly important and highlights the need of understanding the molecular basis on which complicated in vitro and in vivo experiments will be designed on.
2022-03-22 | E-MTAB-11461 | biostudies-arrayexpress
Project description:Toll-like receptor 4 (TLR4) sensing of lipopolysaccharide (LPS), the most potent pathogen-associated molecular pattern of gram-negative bacteria, activates NF-κB and Irf3, which induces inflammatory cytokines and interferons that trigger an intense inflammatory response, which is critical for host defense but can also cause serious inflammatory pathology, including sepsis. Although TLR4 inhibition is an attractive therapeutic approach for suppressing overexuberant inflammatory signaling, previously identified TLR4 antagonists have not shown any clinical benefit. Here, we identify disulfiram (DSF), an FDA-approved drug for alcoholism, as a specific inhibitor of TLR4-mediated inflammatory signaling. TLR4 cell surface expression, LPS sensing, dimerization and signaling depend on TLR4 binding to MD-2. DSF and other cysteine-reactive drugs, previously shown to block LPS-triggered inflammatory cell death (pyroptosis), inhibit TLR4 signaling by covalently modifying Cys133 of MD-2, a key conserved residue that mediates TLR4 sensing and signaling. DSF blocks LPS-triggered inflammatory cytokine, chemokine, and interferon production by macrophages in vitro. In the aggressive N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of Parkinson’s disease (PD) in which TLR4 plays an important role, DSF markedly suppresses neuroinflammation and dopaminergic neuron loss, and restores motor function. Our findings identify a role for DSF in curbing TLR4-mediated inflammation and suggest that DSF and other drugs that target MD-2 might be useful for treating PD and other diseases in which inflammation contributes importantly to pathogenesis.
2023-08-07 | GSE237028 | GEO
Project description:Chronic inflammation is a hallmark of obesity and is linked to the development of numerous diseases. The activation of toll-like receptor 4 (TLR4) by long-chain saturated fatty acids (lcSFAs) is an important process in understanding how obesity initiates inflammation. While experimental evidence supports an important role for TLR4 in obesity-induced inflammation in vivo, via a mechanism thought to involve direct binding to and activation of TLR4 by lcSFAs, several lines of evidence argue against lcSFAs being direct TLR4 agonists. Using multiple orthogonal approaches, we herein provide evidence that while loss-of-function models confirm that TLR4 does, indeed, regulate lcSFA-induced inflammation, TLR4 is not a receptor for lcSFAs. Rather, we show that TLR4-dependent priming alters gene expression, lipid metabolic pathways, and membrane lipid composition, which are necessary for lcSFA-induced inflammation. These results reconcile previous discordant observations and challenge the prevailing view of TLR4's role in initiating obesity-induced inflammation.
2018-04-22 | GSE100526 | GEO
Project description:Interferon (IFN)γ and interleukin (IL)-4 are central regulators of T helper 1 (Th1) and T helper 2 (Th2) immune responses, respectively. Both cytokines have a major impact on macrophage phenotypes: IFNγ–priming and subsequent TLR4 activation induces so called classically activated macrophages that are characterized by pronounced pro-inflammatory responses, whereas IL-4–treated macrophages, commonly called alternatively activated, are known to develop enhanced capacity for endocytosis, antigen presentation, and tissue repair and are generally considered anti-inflammatory. Considering IL-4 as priming rather than activating stimulus, we now compared the TLR4–dependent global gene activation program in IFNγ– versus IL-4–pretreated mouse macrophages, which has rarely been studied so far. Although both cytokines frequently induced opposing effects on gene transcription, the subsequent activation of bone marrow-derived macrophages by lipopolysaccharide (LPS) produced a strong, priming dependent pro-inflammatory response in both macrophage types. For example, the production of key pro-inflammatory cytokines IL-6 and IL-12 was significantly higher in IL-4– versus IFNγ–primed macrophages and several cytokine genes, including Il19, Ccl17, Ccl22, Ccl24 and Cxcl5, were preferentially induced in alternatively primed and LPS activated mouse macrophages. In a subset of genes, including IL12a, IFNγ priming was actually found to suppress LPS–induced gene expression in a Stat1–dependent manner. Our data suggest that IL-4–priming is not per se anti-inflammatory but generates a macrophage that is “tissue protective” but still capable of mounting a strong inflammatory response after TLR4–dependent activation. Keywords: Gene expression profiling
2010-10-01 | GSE21895 | GEO
Project description:Background: Human lung adenocarcinoma (ADC), the predominant subtype of lung cancer, are at a disadvantage as the disease lacks available biomarkers and is not usually diagnosed until its later stages. We previously demonstrated that Tlr4-mutantmice were more susceptible to BHT-induced pulmonary inflammation (bronchoalveolar lavage macrophages and lymphocytes) and tumorigenesis in comparison to Tlr4-sufficient control mice. Differential transcriptional profiles were also noted in the whole lung tissue of the mice. The study objective was to elucidate the mechanisms underlying the protective effect of Tlr4 including differences in specific innate immune cell populations, their functional responses, and the influence of these cellular differences on the growth of ACD progenitor cell types. Methods: Following butylated hydroxytoluene (BHT) treatment (tumor promoter;4 weekly ip.injections), BALB (Tlr4-sufficient) and C.C3-Tlr4Lps-d/J (BALBLpsd; Tlr4 mutant) lungs were lavaged, processed for flow cytometry, and frozen for molecular analysis (ELISAs for IGF1, KC, Raybiotech Mouse Cytokine Array). BALF-derived macrophages were collected for phagocytosis and efferocytosis assays. BALF macrophage RNA was also isolated and utilized for Affymetrix gene arrays and real-time quantitative PCR. Enrichment of bronchiolar Clara cells, an ADC progenitor cell, was performed and cells enumerated. Femur bone marrow cells were differentiated into macrophages, and co-cultured with C10 cells, a type II cell line, for a wound healing assay. Results: Tlr4-deficiency resulted in significantly increased numbers of innate immune cells in whole lung tissue in response to BHT, including macrophages, PMNs, myeloid-derived suppressor cells (MDSC)s and dendritic cells (DCs), in comparison to Tlr4-sufficient mice (p<05). Macrophage functionality was also affected. BHT treated Tlr4-mutant mice demonstrated enhanced phagocytic and efferocytic abilities and wound healing in comparison to macrophages from Tlr4-sufficient and control treated mice (P<0.05). Additionally, Clara cell proliferation was significantly increased in Tlr4-mutant compared to Tlr4-sufficient mice in response to BHT. Pulmonary cytokine, chemokine and growth factor protein expression also significantly differed among the strains and within macrophages, gene expression and cell surface markers combined demonstrated a more plastic macrophage phenotype in the Tlr4-mutant mice. The transcriptome study identified immune pathways important in inflammation, such as phagosome. Conclusion: There are distinct pulmonary innate immune cell populations, with particular emphasis on macrophages, that are likely influencing the enhanced tumor promotion observed in Tlr4-mutant mice. Though not as striking, the pulmonary lymphoid populations may also be affecting the promotion environment, if only via their influence upon the innate immune cells. Future studies will investigate the origins of the macrophages and continued delineation of the lymphoid cell populations. Two strains of mice were used for these studies. The C.C3-Tlr4Lps-d/J (BALBLpsd) with a dominant negative Tlr4 on a BALB/c background and the BALB/cJ mice with a sufficient Tlr4. Total RNA was extracted from bronchoalveolar lavage fluid macrophages 3 days following a chronic BHT protocol. (oil controls vs BHT treated for both strains. BALB oil and BHT treatment n=3 mice per treatment group; BALBLpsd oil controls n=2 per treatment group; BALBLpsd BHT treated n = 3 per treatment group). Therefore a total of 13 arrays with one BHT exposure times and oil (vehicle) controls.
2016-07-14 | E-GEOD-68067 | biostudies-arrayexpress
Project description:To explore the downstream molecules that are responsible for the regulatory role of macrophage-specific TLR4 during inflammatory responses, we analyzed the transcriptome profile of BMDMs isolated from tlr4f/f and tlr4f/f-lysM-Cre mice with or without LPS stimulation by PolyA RNA sequencing.
2021-09-30 | GSE162497 | GEO