Recognition and response to gram-positive bacteria by macrophages and dendritic cells is mediated in part through TLR2. We found that that Streptococcus pneumoniae cell wall fragments, containing primarily peptidoglycan and teichoic acids, induced prodigious secretion of IL-10 from macrophages and dendritic cells and was dependent on TLR2 and NOD2, a cytoplasmic CARD-NACHT-LRR protein encoded by Card15. IL-10 secretion in response to cell walls was also dependent on RICK/RIP2, a kinase associated with NOD2, and MYD88 but independent of the ERK/p38 pathway. The reduction of IL-10 secretion by cell wall-activated NOD2-deficient myeloidderived cells translated into downstream effects on IL-10 target gene expression and elevations in subsets of pro-inflammatory cytokine expression normally restrained by autocrine/paracrine effects of IL-10. Since NOD2 is linked to aberrant immune responses in Crohns Disease patients bearing mutations in CARD15, the temporal and quantitative effects of the TLR2/NOD/RICK pathway on IL-10 secretion may affect homeostatic control of immune responses to gram-positive bacteria.
The TLR2-MyD88-NOD2-RIPK2 signalling axis regulates a balanced pro-inflammatory and IL-10-mediated anti-inflammatory cytokine response to Gram-positive cell walls.
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View SamplesIL-10 regulates anti-inflammatory signaling via the activation of STAT3, which in turn controls the induction of a gene expression program whose products execute inhibitory effects on pro-inflammatory mediator production. Here we show that IL-10 induces the expression of an ETS family transcriptional repressor, ETV3 and a helicase family co-repressor, SBNO2 (Strawberry notch homolog 2) in mouse and human macrophages. IL-10-mediated induction of ETV3 and SBNO2 expression was dependent upon both STAT3, and co-stimulus through the TLR pathway. We also observed that ETV3 expression was strongly induced by the STAT3 pathway induced by IL-10 but not STAT3 signaling activated by IL-6, which cannot activate the anti-inflammatory signaling pathway. ETV3 and SBNO2 specifically repressed NF-kB-mediated transcription and can physically interact. Collectively our data suggest that ETV3 and SBNO2 are components of the pathways that contribute to the downstream anti-inflammatory effects of IL-10.
Cutting edge: A transcriptional repressor and corepressor induced by the STAT3-regulated anti-inflammatory signaling pathway.
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View SamplesNormal human epidermal keratinocytes (NHEK) from neonatal foreskin were cultured in serum-free EpiLife medium with human KC growth supplement (0.2% bovine pituitary extract (v/v), 5ug bovine insulin, 5ug/ml bovine transferrin, 0.5ng/ml human EGF, and 0.18 ug/ml hydrocortisone) from Cascade Biologics. Cultures were treated with recombinant cytokines from R&D Systems. J Immunol. 2007 Feb 15;178(4):2229-40.
The effects of IL-20 subfamily cytokines on reconstituted human epidermis suggest potential roles in cutaneous innate defense and pathogenic adaptive immunity in psoriasis.
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View SamplesA/J mice are genetically predisposed to spontaneous and/or chemically-induced lung tumors while C57BL/6J (B6) mice are resistant. This genetic disparity provides a unique scenario to identify molecular mechanisms associated with the lung response to welding fume at the transcriptome level.
Response of the mouse lung transcriptome to welding fume: effects of stainless and mild steel fumes on lung gene expression in A/J and C57BL/6J mice.
Treatment
View SamplesThis experiment was conducted to test multiple hypotheses: 1) long-wave 365 nm UV light exposure at low fluences does not alter gene expression of hMSC, 2) presence of radical species during polymerization causes DNA damage in hMSC, 3) 3D encapsulation of hMSC causes changes in gene expression of hMSC compared with traditional 2D culture, 4) Differencesin 3D hydrogel networks induce gene expression changes in hMSC
Low-Dose, Long-Wave UV Light Does Not Affect Gene Expression of Human Mesenchymal Stem Cells.
Specimen part
View SamplesThe aim of the experiment was to compare to single and combined effect of Ikaros activation and IL-7 withdrawal in the Ikaros-null pre-B cell line BH1
Ikaros is absolutely required for pre-B cell differentiation by attenuating IL-7 signals.
Specimen part
View SamplesRecent revelations into microRNA function suggest that microRNAs serve as a key player in a robust adaptive response against stress in animals through their fine-tuning capability in gene expression. However, it remains largely unclear how a microRNA-modulated downstream mechanism contributes to the process of homeostatic adaptation. Here we show that loss of an intestinally expressed microRNA gene mir-60 in the nematode C. elegans promotes adaptive response against oxidative stress; animals lacking mir-60 dramatically extend lifespan under a mild and long-term oxidative stress condition, while they do not increase resistance against a strong and transient oxidative stress exposure. We found that canonical stress responsive factors, such as DAF-16/FOXO, are dispensable for mir-60 loss to enhance oxidative stress resistance. Gene expression profiles revealed that genes encoding lysosomal proteases and those involved in the xenobiotic metabolism and pathogen defense response are up-regulated by the mir-60 loss. Detailed genetic studies and computational microRNA target prediction suggest that endocytosis components and a bZip transcription factor gene zip-10, which functions in innate immune response, are directly modulated by miR-60 in the intestine. Our findings suggest that the mir-60 loss facilitates adaptive response against chronic oxidative stress by ensuring the maintenance of cellular homeostasis. Overall design: To identify genes that respond to the mir-60 loss, RNA expression profiles were examined between the mir-60 loss mutant (mir-60(n4947)) and its control animals using the high-throughput sequencing technology. In this study, we used spe-9(hc88), a temperature-sensitive sterile strain, which has been shown in previous studies to have a lifespan similar to wild-type and widely used in gene expression studies to reduce the effect of RNA contamination from younger progenies. Both spe-9 single and mir-60;spe-9 double mutant animals were cultured at a restrictive temperature 23.5 °C, and treated with paraquat 5 mM during adulthood for chronic oxidative stress. Total RNAs were purified at the following time points: Day 0 young adult for both spe-9 and mir-60;spe-9 (just before paraquat exposure); Day 7 for both spe-9 and mir-60;spe-9 (50% survival time for spe-9); Day 10 for mir-60;spe-9 (50% survival time for mir-60;spe-9). For Day 0 controls, total RNAs were isolated twice independently for biological replicates. cDNA libraries were made for these 7 samples with indexed adapters using TruSeq Stranded mRNA Sample Prep Kit (Illumina), and sequenced on 2 lanes of flow cells on the HiSeq 2000/2500 platform, eventually providing 14 sequencing samples.
An intestinal microRNA modulates the homeostatic adaptation to chronic oxidative stress in <i>C. elegans</i>.
Specimen part, Treatment, Subject, Time
View SamplesMED23, a subunit of the Mediator coactivator complex, is important for the expression of a subset of MAPK/ERK pathway-dependent target genes; however, the genes in this subset varies between cell types. MAPK/ERK pathway-dependent processes are essential for T-cell development and function, but whether MED23 has a role in this context is unknown. We generated Med23 conditional knockout mice and induced Med23 deletion in early T cell development using the lineage specific Lck-Cre transgene. While the total cell number and distribution of cell populations in the thymuses of Med23flox/flox;Lck-Cre mice were essentially normal, MED23 null T-cells failed to efficiently populate the peripheral lymphoid organs. MED23 null thymocytes displayed decreased expression of the MAPK/ERK-responsive genes Egr1, Egr2, as well as of the membrane glycoprotein Cd52 (CAMPATH-1). MED23 null CD4 single-positive thymocytes also showed decreased expression of KLF2 (LKLF), a T cell master regulatory transcription factor. Indeed, similarities between the phenotypes of mice lacking MED23 or KLF2 in T-cells suggest that KLF2 deficiency in MED23 null T-cells is one of their key defects. Mechanistic experiments using MED23 null MEFs further suggest that MED23 is required for full activity of the MAPK-responsive transcription factor MEF2, which has previously been shown to mediate Klf2 expression. In summary, our data indicate that MED23 has critical roles in enabling T-cells to populate the peripheral lymphoid organs, possibly by potentiating MEF2-dependent expression of the T-cell transcription factor KLF2.
T-cells null for the MED23 subunit of mediator express decreased levels of KLF2 and inefficiently populate the peripheral lymphoid organs.
Sex, Specimen part
View SamplesXBP1 is a transcription factor that is induced by unconventional splicing associated with endoplasmic reticulum stress and plays a role in development of liver and plasma cells. We previously reported that brain derived neurotrophic factor (BDNF) leads to splicing of XBP1 mRNA in neurites, and that XBP1 is required for BDNF-induced neurite extension and branching. To search for the molecular mechanisms of how XBP1 plays a role in neural development, comprehensive gene expression analysis was performed in primary telencephalic neurons obtained from Xbp1 knockout mice at embryonic day 12.5. By searching for the genes induced by BDNF in wild type neurons but this induction was reduced in Xbp1 knockout mice, we found that upregulation of three GABAergic markers, somatostatin (Sst), neuropeptide Y (Npy), and calbindin (Calb1), were compromised in Xbp1 knockout neurons. Attenuated induction of Npy and Calb1 was confirmed by quantitative RT-PCR. In neurons lacking in Xbp1, upregulation of GABAergic markers was attenuated. Impaired BDNF-induced neurite extension in Xbp1 knockout neurons might be mediated by disturbed BDNF-induced differentiation of GABAergic interneurons.
Attenuated BDNF-induced upregulation of GABAergic markers in neurons lacking Xbp1.
Specimen part
View SamplesDifferentiation of human skeletal stem cells (hMSC) into osteoblasts is regulated by a few well described transcription factors. Our study used clustering and gene expression data to identify a novel transcription factor. ZNF25, which we showed is involved in osteoblast differentiation.
Transcription factor ZNF25 is associated with osteoblast differentiation of human skeletal stem cells.
Cell line
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