Project description:Proinflammatory stimuli rapidly and globally remodel chromatin landscape, thereby enabling transcriptional responses. Yet, the mechanisms coupling chromatin regulators to the master regulatory inflammatory transcription factor NF-kB remain poorly understood. We report in human endothelial cells (ECs) that activated NF-kB binds to enhancers, provoking a rapid, global redistribution of BRD4 preferentially at super-enhancers, large enhancer domains highly bound by chromatin regulators. Newly established NF-kB super-enhancers drive nearby canonical inflammatory response genes. In both ECs and macrophages BET bromodomain inhibition prevents super-enhancer formation downstream of NF-kB activation, abrogating proinflammatory transcription. In TNFa-activated endothelium this culminates in functional suppression of leukocyte rolling, adhesion and transmigration. Sustained BET bromodomain inhibitor treatment of LDLr -/- animals suppresses atherogenesis, a disease process rooted in pathological vascular inflammation involving endothelium and macrophages. These data establish BET-bromodomains as key effectors of inflammatory response through their role in the dynamic, global reorganization of super-enhancers during NF-kB activation. Gene expression analysis of human endothelial cells in resting state, treatment with TNFalpha or TNFalpha with the BET bromodomain inhibitor JQ1
Project description:Proinflammatory stimuli rapidly and globally remodel chromatin landscape, thereby enabling transcriptional responses. Yet, the mechanisms coupling chromatin regulators to the master regulatory inflammatory transcription factor NF-kB remain poorly understood. We report in human endothelial cells (ECs) that activated NF-kB binds to enhancers, provoking a rapid, global redistribution of BRD4 preferentially at super-enhancers, large enhancer domains highly bound by chromatin regulators. Newly established NF-kB super-enhancers drive nearby canonical inflammatory response genes. In both ECs and macrophages BET bromodomain inhibition prevents super-enhancer formation downstream of NF-kB activation, abrogating proinflammatory transcription. In TNFa-activated endothelium this culminates in functional suppression of leukocyte rolling, adhesion and transmigration. Sustained BET bromodomain inhibitor treatment of LDLr -/- animals suppresses atherogenesis, a disease process rooted in pathological vascular inflammation involving endothelium and macrophages. These data establish BET-bromodomains as key effectors of inflammatory response through their role in the dynamic, global reorganization of super-enhancers during NF-kB activation. Chem-Seq for the biotinylated small molecule JQ1 in untreated or TNFalpha treated human endothelial cells
Project description:Comparison of gene expression profiles of the GL261 cell line (a murine glioma model) grown in duplicate in two different types of media. AC samples where grown in DMEM supplemented by 20% FBS, 5 U/ml pen/strep and 4 mM L-glutamine. NS samples were grown in DMEM/F12 (50/50) supplemented with 2 U/ml pen/strep, 1 ug/ml fungizone, 1x B27, 20 ng/ml bFGF, 20 ng/ml EGF, 20 ng/ml LIF and 5 ug/ml heparin. We have reason to believe the NS media enhances cell de-differentiation.
Project description:Proinflammatory stimuli rapidly and globally remodel chromatin landscape, thereby enabling transcriptional responses. Yet, the mechanisms coupling chromatin regulators to the master regulatory inflammatory transcription factor NF-kB remain poorly understood. We report in human endothelial cells (ECs) that activated NF-kB binds to enhancers, provoking a rapid, global redistribution of BRD4 preferentially at super-enhancers, large enhancer domains highly bound by chromatin regulators. Newly established NF-kB super-enhancers drive nearby canonical inflammatory response genes. In both ECs and macrophages BET bromodomain inhibition prevents super-enhancer formation downstream of NF-kB activation, abrogating proinflammatory transcription. In TNFa-activated endothelium this culminates in functional suppression of leukocyte rolling, adhesion and transmigration. Sustained BET bromodomain inhibitor treatment of LDLr -/- animals suppresses atherogenesis, a disease process rooted in pathological vascular inflammation involving endothelium and macrophages. These data establish BET-bromodomains as key effectors of inflammatory response through their role in the dynamic, global reorganization of super-enhancers during NF-kB activation. ChIP-Seq for various transcription factors, RNA Polymerase II, and histone modifications in human endothelial cells
Project description:Both targeted inhibition of oncogenic driver mutations and immune-based therapies show efficacy in treatment of patients with metastatic cancer but responses are either short-lived or incompletely effective. Oncogene inhibition can augment the efficacy of immune-based therapy but mechanisms by which these two interventions might cooperate are incompletely resolved. Using a novel transplantable BRAFV600E-mutant murine melanoma model (SB-3123), we explore potential mechanisms of synergy between the selective BRAFV600E inhibitor vemurafenib and adoptive cell transfer (ACT)-based immunotherapy. We found that vemurafenib cooperated with ACT to delay melanoma progression but surprisingly did not enhance tumor infiltration or effector function of endogenous or adoptively transferred CD8+ T cells as previously observed. Instead, we found that the T cell cytokines IFN-gamma and TNF-alpha synergized with vemurafenib to induce cell cycle arrest of tumor cells in vitro. This was recapitulated in vivo as continuous vemurafenib administration was required to delay melanoma progression following ACT. The unexpected finding that immune cytokines synergize with oncogene inhibitors to induce growth arrest have major implications for understanding cancer biology at the intersection of oncogenic and immune signaling and provides a basis for design of combinatorial therapeutic approaches for patients with metastatic cancer. SB-3123p cells were treated in triplicate (biological replicates) under the following conditions for 96 hours: DMSO vehicle (control) (n=3); mouse IFNgamma (2.4 ng/ml) and mouse TNFalpha (0.24 ng/mL) (n=3); Vemurafenib (1uM) (n=3); and mouse IFNgamma (2.4 ng/ml), mouse TNFalpah (0.24 ng/mL) and Vemurafenib (1uM) (n=3).
Project description:Using measles virus induced T cell suppression as a model, we established that T cell inhibitory protein isoforms can be produced from alternatively spliced pre-mRNAs as a result of virus-mediated ablation of T cell receptor dependent activation of the phosphatidylinositol-3-kinase (PI3K). To asses production of alternative splice variants in response to PI3K abrogation in T cells at a whole cell level, we performed a Human Exon 1.0 ST Array on RNAs isolated from T cells stimulated only or stimulated after PI3K inhibition. We developed a simple algorithm based on a splicing index to detect genes that undergo alternative splicing (AS) or are differentially regulated (RG) on T cell suppression. Applying our algorithm on this model 9% of the genes were assigned as AS, while only 3% were attributed to RG. Though there are overlaps, AS and RG genes differed with regard to functional regulated at the level of AS or RG were found enriched in different functional groups with AS targeting e. g. extra cellular matrix (ECM)-receptor interaction and focal adhesion, while cytokine-receptor interaction, Jak-STAT and p53 pathways were mainly RG. When combined, AS/RG dependent alterations targeted pathways essential for T cell receptor signaling, cytoskeletal dynamics and cell cycle entry strongly supporting the notion that PI3K abrogations interferes with key T cell activation processes at both levels, and that candidates represented within both categories bear the potential to actively contribute to T cell suppression total samples analysed are 8: 4 stimulated and 4 stimulated and inihibited from 4 donors
Project description:Chronic Otitis Media (OM) develops after sustained inflammation and is characterized by secretory middle ear epithelial metaplasia and effusion, most frequently mucoid. Non-typeable Haemophilus influenzae (NTHi), the most common acute OM pathogen, is known to activate inflammation and mucin expression in vitro and in animal models of OM. The goals of this study were to: examine expression profiling epithelial effects of NTHi challenge in murine middle ears. We used microarrays to detail examine the global programme of gene expression underlying epithelial effects of NTHi challenge in murine middle ears during this study. Weekly transtympanic inoculation of Balb/c mice with 300 µg/ml of NTHi lysates vs saline was performed. Bacteria were grown on chocolate agar at 37ºC in 5% CO2 overnight and inoculated in brain heart infusion (BHI) broth supplemented with 3.5 mg of nicotinamide adenine dinucleotide per ml. After overnight incubation, bacteria were subcultured into 5 ml of fresh brain heart infusion (BHI) and upon reaching log phase growth, NTHi were washed and suspended in phosphate-buffered saline (PBS) followed by sonication for lysis. Three transtympanic inoculation of 6 Balb/c mice middle ears (3 animals, 6 ears) with 50 uL of 300 ug/ml of NTHi bacterial lysate and 6 Balb/c mice middle ears (3 animals, 6 ears) with 50 uL of 1X phosphate buffered saline (PBS) were carried out weekly over 4 weeks (injection on days 7, 14, and 21). On day 28, the mice were euthanized and their bullae harvested. Expression microarray analysis was performed at 1 and 7 days. Microarray findings were validated in independent animal samples and in a cultured murine middle ear epithelial cell (mMEEC) line.
Project description:The aim of this study was to characterize the impact of differential HIV opsonization on DC modulation. DCs are the most potent antigen-presenting cells and among the first cells HIV is attaching to. HIV spontaneously activates the complement system even in the absence of specific antibodies and is therefore found opsonized with complement fragments from the beginning of infection. Gene expression profiles of DCs from three different human donors and treated for 24 hrs with 100 ng/ml LPS, 300 ng/ml non-opsonized HIV (HIV-MC), or 300 ng/ml complement-opsonized (HIV-C) were compared to those of untreated immature DCs.