Project description:The experiment was designed to determine the gene expression changes cultured brown adipocytes in response to the inflammatory stimulus of LPS treatment. Both wild type and TLR4 knockout cells were applied to enable assessment of the contribution of TLR4 to the response.
Project description:This is an investigation of whole genome gene expression level in tissues of mice stimulated by LPS, FK565 or LPS + FK565 in vivo and ex vivo. We show that parenteral administration of a pure synthetic Nod1 ligand, FK565, induces site-specific vascular inflammation in mice, which is prominent in aortic root including aortic valves, slight in aorta and absent in other arteries. The degree of respective vascular inflammation is associated with persistent high expression of proinflammatory chemokine/cytokine genes in each tissue in vivo by microarray analysis, and not with Nod1 expression levels. The ex vivo production of proinflammatory chemokine/cytokine by Nod1 ligand is higher in aortic root than in other arteries from normal murine vascular tissues, and also higher in human coronary artery endothelial cells (HCAEC) than in human pulmonary artery endothelial cells (HPAEC), suggesting that site-specific vascular inflammation is at least in part ascribed to an intrinsic nature of the vascular tissue/cell itself. A fourty chip study using total RNA recovered from four isolated tissues of mice which were stimulated by various reagents. Aortic root, pulmonary artery, aorta and spleen of mice in 3 groups: 1) intraperitoneal injection of 20M-NM-<g of LPS priming only, 2) oral administration of FK565 (100M-NM-<g) for consecutive days, 3) oral administration of FK565 (100M-NM-<g) for consecutive days 1 day after LPS priming, at day 2, 4, and 7. And six chip study using total RNA recovered from three isolated vascular tissues of mice which were stimulated by FK565 (10M-NM-<g/mL) ex vivo.
Project description:This is an investigation of whole genome gene expression level in tissues of mice stimulated by LPS, FK565 or LPS + FK565 in vivo and ex vivo. We show that parenteral administration of a pure synthetic Nod1 ligand, FK565, induces site-specific vascular inflammation in mice, which is prominent in aortic root including aortic valves, slight in aorta and absent in other arteries. The degree of respective vascular inflammation is associated with persistent high expression of proinflammatory chemokine/cytokine genes in each tissue in vivo by microarray analysis, and not with Nod1 expression levels. The ex vivo production of proinflammatory chemokine/cytokine by Nod1 ligand is higher in aortic root than in other arteries from normal murine vascular tissues, and also higher in human coronary artery endothelial cells (HCAEC) than in human pulmonary artery endothelial cells (HPAEC), suggesting that site-specific vascular inflammation is at least in part ascribed to an intrinsic nature of the vascular tissue/cell itself.
Project description:Toll-like receptor 4 (TLR4) plays a pivotal role in the host response to lipopolysaccharide (LPS), a major cell wall component of Gram-negative bacteria. Here we elucidated whether the endocytic adaptor protein Disabled-2 (Dab2) that is abundantly expressed in the macrophages plays a role in LPS-stimulated TLR4 signaling and trafficking. Molecular analysis and transcriptome profiling of the RAW264.7 macrophage-like cells expressing short-hairpin RNA of Dab2 revealed that Dab2 mainly regulated LPS-stimulated TRIF-dependent, but not MyD88-dependent TLR4 signaling. Consequently, knockdown of Dab2 augmented TRIF-dependent interferon regulatory factor 3 activation and the expression for the subsets of inflammatory cytokines and interferon-inducible genes. We further delineated that Dab2 acted as a “clathrin sponge” and sequestered clathrin from TLR4/MD2 complex in the resting stage of macrophages. Clathrin was released from Dab2 and associated with TLR4 to facilitate the internalization of TLR4/MD2 complex together with the bound ligand from the cell surface upon LPS stimulation. Dab2 thereby functions as a negative immune regulator of TLR4 endocytosis and signaling, supporting a novel role of Dab2-associated regulatory circuit in the control of inflammatory response of macrophage to endotoxin.
