Project description:We used I-BET 151, an isoxazoloquinoline that specifically inhibits interaction of BET proteins with acetylated histones to restrict inflammatory tissue priming in a mouse model of iterated monosodium urate (MSU) crystal-induced arthritis. Systemic administration of I-BET 151 abolished the enhancement of arthritis upon repeated injection of MSU crystals.
Project description:Objective. To identify novel monosodium urate (MSU) crystal-induced mRNAs by transcript profiling of isolated murine air pouch membranes. Methods. Nine hours after injecting crystals into air pouches, membranes were meticulously dissected away from the adjacent soft tissues. mRNA expression differences between inflamed and control membranes were determined by oligonucleotide microarray analysis. Induction of selected mRNAs was validated by real-time relative quantitative reverse transcriptase PCR (qPCR) in pouch membranes and murine peritoneal macrophages. Results. Eleven of the 12 most highly upregulated mRNAs related to innate immunity and inflammation. They included mRNAs encoding histidine decarboxylase (the enzyme that synthesizes histamine), interleukin (IL)-6, the cell surface receptors PUMA-g and TREM-1, and the polypeptides Irg1 and PROK-2. MSU crystals induced dramatic rises in these mRNAs in the pouch membrane within 3-8 hours after the surge in pro-inflammatory cytokine (IL-6, IL-1beta and TNFalpha) and immediate early gene (Egr-1) transcription, which occurred 1h after crystal injection. MSU crystals induced these mRNAs in cultured macrophages with similar kinetics but lower fold changes. In keeping with their downregulation by MSU crystals according to the microarrays, qPCR confirmed that TREM-2 and granzyme D mRNAs decreased 79% and 94%, respectively, in MSU crystal inflamed membranes. Conclusions. This analysis disclosed several genes previously not implicated in MSU crystal inflammation. Their rise after the early surge in cytokine mRNAs suggests that they may, for instance, amplify or perpetuate inflammation. Transcript profiling of the isolated air pouch membrane promises to be a powerful tool to identify genes acting at different stages of inflammation.
Project description:Objective. To identify novel monosodium urate (MSU) crystal-induced mRNAs by transcript profiling of isolated murine air pouch membranes. Methods. Nine hours after injecting crystals into air pouches, membranes were meticulously dissected away from the adjacent soft tissues. mRNA expression differences between inflamed and control membranes were determined by oligonucleotide microarray analysis. Induction of selected mRNAs was validated by real-time relative quantitative reverse transcriptase PCR (qPCR) in pouch membranes and murine peritoneal macrophages. Results. Eleven of the 12 most highly upregulated mRNAs related to innate immunity and inflammation. They included mRNAs encoding histidine decarboxylase (the enzyme that synthesizes histamine), interleukin (IL)-6, the cell surface receptors PUMA-g and TREM-1, and the polypeptides Irg1 and PROK-2. MSU crystals induced dramatic rises in these mRNAs in the pouch membrane within 3-8 hours after the surge in pro-inflammatory cytokine (IL-6, IL-1beta and TNFalpha) and immediate early gene (Egr-1) transcription, which occurred 1h after crystal injection. MSU crystals induced these mRNAs in cultured macrophages with similar kinetics but lower fold changes. In keeping with their downregulation by MSU crystals according to the microarrays, qPCR confirmed that TREM-2 and granzyme D mRNAs decreased 79% and 94%, respectively, in MSU crystal inflamed membranes. Conclusions. This analysis disclosed several genes previously not implicated in MSU crystal inflammation. Their rise after the early surge in cytokine mRNAs suggests that they may, for instance, amplify or perpetuate inflammation. Transcript profiling of the isolated air pouch membrane promises to be a powerful tool to identify genes acting at different stages of inflammation. Experiment Overall Design: Mouse strain: female Balb/C, 6-8 weeks old Experiment Overall Design: Number of mice= 6. Experiment Overall Design: Air pouches raised on back for 7 days by injecting 2ml of sterile air. Experiment Overall Design: On day 7, injection of 1ml PBS or 2mg MSU crystals in 1ml PBS (n=3 each) Experiment Overall Design: 9 h after injection, dissection of the air pouch membranes from the adjacent soft tissues, RNA extraction with RNeasy columns. Pooling of RNA from the 3 control pouches or the 3 MSU crystal pouches. Processing and labeling of 5ug aliquots in the U Penn microarray core according to standard Affy protocols. Hybridization to Affy Mo430_2 oligonucleotide microarrays.
Project description:Aim of the study was to characterize at a molecular level (changes in transcriptomes) the effect of monosodium urate crystal (MSU) on HaCaT keratinocyte cell line. This was adressed by using a culture model. The HaCaT cell line (human keratinocytes) was stimulated by MSU (1mg/mL) vs control for 12 hrs. By using genome-wide expression profiling, we identified deregulation of functionally relevant gene networks.
Project description:Exposure to physical particles is a driver of several inflammatory diseases. Here, we systematically investigated responses of macrophages to pathogenic forms of monosodium urate crystals, calcium pyrophosphate crystals, aluminium salts, and silica nanoparticles. While each particle induced a distinct pattern of gene expression, we also identified a common signature that was preferentially linked to inflammation and acute activation of genes required for lysosomal acidification. Using monosodium urate crystals as a model system, we obtained evidence that the program of lysosomal gene expression was regulated by a network of transcription factors that included TFEB and TFE3 and the epigenetic regulators DNMT3A and DOT1L. This lysosomal acidification network operated in parallel with, but largely independently of, a JNK and AP-1 dependent transcription factor network that drove crystal induced chemokine and cytokine gene expression. Mechanistically, the uptake of particles led to early activation of AMPK signalling that was required for activation of TFEB and TFE3 in a process independent of reduced mTOR signalling. These results thereby revealed a mechanism by which the functions of TFEB and TFE3 can be preferentially targeted to specific aspects of lysosomal gene expression, which may provide insights into therapeutic approaches to treat individuals with particle-associated diseases.
Project description:Muramyl dipeptide (MDP) and Monosodium urate crystals (MSU) promote a synergistic effect on NOD2 and NLRP3 with a unique transcriptional profile in murine dendritic cells
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:Aim of the study was to characterize at a molecular level (changes in transcriptomes) the effect of monosodium urate crystal (MSU) on HaCaT keratinocyte cell line. This was adressed by using a culture model. The HaCaT cell line (human keratinocytes) was stimulated by MSU (1mg/mL) vs control for 12 hrs. By using genome-wide expression profiling, we identified deregulation of functionally relevant gene networks. HaCaT were obtained from Cell Lines Service (Eppelheim, Germany) and grown in DMEM medium (PAN biotech, Aidenbach, Germany) supplemented with 10% FBS (Life Technology, Grand Island, NY, USA), L-glutamine and non-essential amino acid. Before the treatment HaCaT cells were cultured in serum-free medium for 12hrs. HaCaT were treated with MSU (1mg/ml) vs DMEM control for 12hrs then submitted to RNA extration and gene expression profiling. Triplicate experiments were performed: HaCaT control (n=3), MSU-treated (n=3).