Home About us Contact | |||
Addressin Cell Adhesion (addressin + cell_adhesion)
Kinds of Addressin Cell Adhesion Selected AbstractsA pseudosymmetric cell adhesion regulatory domain in the ,7 tail of the integrin ,4,7 that interacts with focal adhesion kinase and srcEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2006Geoffrey Abstract The ,7 integrins ,4,7 and ,E,7 play key roles in forming the gut-associated lymphoid tissue, and contribute to chronic inflammation. The ,4,7 integrin-mediated adhesion of activated lymphocytes is largely due to a transient increase in avidity from ligand-induced clustering of ,4,7 at the cell-surface. Here, we report that L and D enantiomers of a cell-permeable peptide YDRREY encompassing residues 735,740 of the cytoplasmic tail of the ,7 subunit inhibit the adhesion of T cells to ,7 integrin ligands. The YDRREY peptide abrogated mucosal addressin cell adhesion molecule-1-induced clustering of ,4,7 on the surface of activated T cells. A mutated form of the YDRREY peptide carrying either single or double conservative mutations at Tyr735Phe and Tyr740Phe was unable to inhibit T cell adhesion, suggesting that both tandem tyrosines are critical for activity. The YDRREY peptide was bound and phosphorylated by focal adhesion kinase and src, which may serve to sequester cytoskeletal proteins to the cytoplasmic domain of ,4,7. The quasi-palindromic sequence YDRREY within the ,7 cytoplasmic tail constitutes a cell adhesion regulatory domain that modulates the interaction of ,7-expressing leukocytes with their endothelial and epithelial ligands. Cell-permeable peptidomimetics based on this motif have utility as anti-inflammatory reagents for the treatment of chronic inflammatory disease. [source] Down-regulation of endothelial adhesion molecules and leukocyte adhesion by treatment with superoxide dismutase is beneficial in chronic immune experimental colitisINFLAMMATORY BOWEL DISEASES, Issue 10 2005Joaquim Seguí PhD Abstract Modulation of adhesion molecule expression that govern trafficking of leukocytes into the inflamed intestine is envisioned as a new strategy for treatment of inflammatory bowel disease (IBD). This study was designed to determine the impact of reducing oxidative stress on adhesion molecules expression and leukocyte recruitment in experimental chronic colitis. For that purpose, colitic interleukin-10 knockout and wild-type mice were studied. Groups of animals were treated with Cu/Zn superoxide dismutase (SOD1) 13 mg/kg/d or vehicle for either 7 or 14 days. Expression of vascular cell adhesion molecule-1 and mucosal addressin cell adhesion molecule-1 were determined; leukocyte-endothelial cell interactions in colonic venules were studied with intravital microscopy; and changes in colon pathology and biomarkers of colitis severity were determined. Development of colitis was associated with a marked increase in endothelial vascular cell adhesion molecule-1 and mucosal addressin cell adhesion molecule-1 expression, which were significantly reduced by treatment with SOD1. The increase in leukocyte rolling and adhesion in colonic venules of colitic mice were significantly reduced by administration of SOD1. This treatment markedly reduced colonic lipid hydroperoxidation, myeoloperoxidase activity, and plasma levels of serum amyloid A protein and resulted in significant, although modest, reductions in histologic damage score. The therapeutic value of SOD1 when administered prophylactically was assessed in the dextran sulfate sodium model of colitis with similar positive results. These results indicate that SOD1 affords significant amelioration of colonic inflammatory changes in experimental colitis. Down-regulation of adhesion molecule expression, reduction of lipid hydroperoxidation, and recruitment of leukocytes into the inflamed intestine contribute to this beneficial effect. [source] Expression of Cell Adhesion Molecules at the Collapse and Recovery of Haematopoiesis in Bone Marrow of MouseANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010T Tada With 8 figures Summary After bone marrow transplantation (BMT) and lethal irradiation, vascular endothelial cells play an important role in the homing of haematopoietic cells and recovery of haematopoiesis. We investigated the expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1), vascular cell adhesion molecule-1 (VCAM-1) and fibronectin in the endothelial cells of bone marrow in a collapsed state after lethal irradiation and in a recovery state after BMT in mice. After lethal irradiation, the expression of MAdCAM-1, VCAM-1 and fibronectin increased on the luminal surface of endothelial cells. In the recovery state, the expression of MAdCAM-1 and VCAM-1 was increased from 2 to 4 days after BMT, but fibronectin levels remained constant, except for a temporary increase at 4 days after BMT. The number of homing cells, however, was markedly decreased in parallel with the reduction in the haematopoietic compartment at 2 and 4 days after lethal irradiation. Next, to analyse the influence of fibronectin expression after BMT on homing activity, we performed double BMT experiment. The number of homing cells in double BMT experiment maintained high level from 2 h to 2 days after secondary BMT. Our data suggest that homing of bone marrow cells is activated until fibronectin-mediated endothelial cell repair and that transplanted haematopoietic stem/progenitor cells inhibit fibronectin expression for endothelial cell repair until the homing is completed. Therefore, the homing of haematopoietic cells in bone marrow depends on the condition of the bone marrow endothelial cells, as well as the cell adhesion molecules. [source] Omega-3 polyunsaturated fatty acids ameliorate the severity of ileitis in the senescence accelerated mice (SAM)P1/Yit mice modelCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2009H. Matsunaga Summary Clinical studies using omega-3 polyunsaturated fatty acids (,3-PUFA) to Crohn's disease (CD) are conflicting. Beneficial effects of dietary ,3-PUFA intake in various experimental inflammatory bowel disease (IBD) models have been reported. However, animal models of large intestinal inflammation have been used in all previous studies, and the effect of ,3 fat in an animal model of small intestinal inflammation has not been reported. We hypothesized that the effects of ,3 fat are different between large and small intestine. The aim of this study was to determine whether the direct effect of ,3 fat is beneficial for small intestinal inflammation. Senescence accelerated mice (SAM)P1/Yit mice showed remarkable inflammation of the terminal ileum spontaneously. The numbers of F4/80-positive monocyte,macrophage cells as well as ,7-integrin-positive lymphocytes in the intestinal mucosa were increased significantly compared with those in the control mice (AKR-J mice). The area of mucosal addressin cell adhesion molecule-1 (MAdCAM-1)-positive vessels was also increased. The degree of expression levels of monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-6 and interferon (IFN)-, mRNA were increased significantly compared with those in the control mice. The feeding of two different kinds of ,3 fat (fish-oil-rich and perilla-oil-rich diets) for 16 weeks to SAMP1/Yit mice ameliorated inflammation of the terminal ileum significantly. In both the ,3-fat-rich diet groups, enhanced infiltration of F4/80-positive monocytes/macrophages in intestinal mucosa of SAMP1/Yit mice cells and the increased levels of MCP-1, IL-6 and IFN-, mRNA expression were ameliorated significantly compared with those in the control diet group. The results suggest that ,3 fat is beneficial for small intestinal inflammation by inhibition of monocyte recruitment to inflamed intestinal mucosa. [source] |