Project description:Over-expression of miR-155 induces changes in the pattern of gene expression of hCMEC/D3 cells. hypothesis tested in the present study was that miR-155 constitute an important regulatory control of the brain endothelial response to inflammatory cytokines. To identify miR-155 target genes in brain endothelim that might be implicated in BBB dysfunction relevant to human disease, we then analysed changes in mRNA expression of hCMEC/D3 cells that overexpress miR-155 and results were contrasted to cells transfected with scrambled miR. To ectopically express miR-155 in hCMEC/D3 cells, 30 nM of pre-miR-155 and the siPORT Amine transfection agent (Applied Biosystems, Warrington, UK) were combined following the manufacturerM-bM-^@M-^Ys instructions.
Project description:Over-expression of miR-155 induces changes in the pattern of gene expression of hCMEC/D3 cells. hypothesis tested in the present study was that miR-155 constitute an important regulatory control of the brain endothelial response to inflammatory cytokines.
Project description:Here, we investigated the time-course changes in the pattern of microRNA (miRNA) expression of TNFα and IFNγ-stimulated and unstimulated hCMEC/D3 cells, an immortalized human cerebral microvascular endothelial cell line. In order to investigate pro-inflammatory cytokine-induced changes in miRNA levels in hCMEC/D3 cells, we challenged brain endothelial cells with TNFα and IFNγ (100 ng/ml) for 2 h, 6 h and 24 h and determined microRNA expression in cytokine-stimulated and unstimulated cells
Project description:Here, we investigated the time-course changes in the pattern of microRNA (miRNA) expression of TNFα and IFNγ-stimulated and unstimulated hCMEC/D3 cells, an immortalized human cerebral microvascular endothelial cell line.
Project description:MicroRNA (miRNA)-mediated mRNA regulation directs many homeostatic and pathological processes, but how miRNAs coordinate aberrant esophageal inflammation during eosinophilic esophagitis (EoE) is poorly understood. Here, we report a deregulatory axis where microRNA-155 (miR-155) regulates epithelial barrier dysfunction by selectively constraining tight junction CLDN7 (claudin-7). MiR-155 is elevated in the esophageal epithelium of biopsies from patients with active EoE and in cell culture models. miR-155 localisation using in situ hybridisation (ISH) in patient biopsies, and intra-epithelial compartmentalisation of miR-155 shows expression predominantly within the basal epithelia. Epithelial miR-155 activity was evident through diminished target gene expression in 3D organotypic cultures, particularly in relatively undifferentiated basal cell states. Mechanistically, generation of a novel cell line with enhanced epithelial miR-155 stable overexpression induced a functionally deficient epithelial barrier in 3D air-liquid interface epithelial cultures measured by transepithelial electrical resistance (TEER). Histological assessment of 3D esophageal organoid cultures overexpressing miR-155 showed notable dilated intra-epithelial spaces. Unbiased RNA-sequencing analysis and immunofluorescence determined a defect in epithelial barrier tight junctions and revealed a selective reduction in the expression of critical esophageal tight junction molecule, claudin-7. Together, our data reveal a previously unappreciated role for miR-155 in mediating epithelial barrier dysfunction in esophageal inflammation.
Project description:Electronic cigarette (EC) use has grown substantially since entry into the US market, particularly among adolescents and combustible tobacco users. Despite growing popularity and claims of harm reduction, the health effects of these products outside the lung is poorly understood. Several constituents of cigarette smoke (CS) with known neurovascular and inflammatory effects are present in EC liquids or formed during the generation of vapor. The present study characterizes the impact of EC exposure on neuroinflammation and blood-brain barrier (BBB) function, and provides comparison of outcomes with reference cigarette exposure normalized to comparable levels of nicotine delivery. Additionally, the contribution of nicotine to observed effects is elucidated through comparison with EC liquids which are verified to be nicotine-free. C57BL/6 mice are exposed to 2 hrs of daily EC vapor or CS, beginning at 8 wks of age. Changes in BBB gene expression are first characterized by whole exome sequencing of isolated brain microvessels following chronic (2 month) EC exposure.