Analysis of ICAM-1-independent intestinal epithelial cell adhesion to neutrophils
Grant-in-Aid for Scientific Research (C).
|Research Institution||Juntendo University|
SOMEYA Akimasa Juntendo University, School of Medicine, Assistant Professor, 医学部, 講師 (90167479)
|Project Fiscal Year
1998 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥2,200,000 (Direct Cost : ¥2,200,000)
|Keywords||Intestinal epithelial cell / Neutrophil / Inflammation / Adhession molecule / Inflammatory mediator / Cytokine / TNF-α / Histamine / 腸管上皮細胞 / 好中球 / 炎症 / 接着分子 / 炎症性メディエーター / サイトカイン / ヒスタミン|
Neutrophils play an important role in intestinal inflammation by interacting with intestinal epithelial cells. In this study, we evaluated neutrophil adhesion to intestinal epithelial cells using intestinal epithelial cell line HT29 stimulated with tumor necrosis factor a (TNF-α) and histamine.
(1) The TNF-α and histamine stimulation markedly increased neutrophil adhesion. The increased adhesion was inhibited by anti-CD11b and anti-CD18 antibodies, but not by anti-CD11a and anti-CD54 (ICAM- 1) antibodies.
(2) Interestingly, flow cytometric analysis revealed that ICAM-1 expression on HT29 cells was not changed by TNF-αand histamine stimulation. These observations indicate that exposure of HT29 cells to TNF-αand histamine induces CD11b/CD18 (Mac-1)-dependent but CD11a/CD18 (LFA-1)-independent neutrophil adhesion to intestinal epithelial cells, and ICAM-1 is not likely involved in the interactions.
(3) Moreover, the increased adhesion was inhibited by proteinase K treatment but not cyclohexi
mide treatment of HT29 cells, suggesting that epithelial cell ligand(s) for neutrophils is likely protein molecule(s) that is exposed on the cell by stimulation independent of protein synthesis.
(4) Even when HT29 cells were treated with endoglycosidase H, sialidase or tunicamycin, neutrophil adhesion to TNF-α- or histamine-stimulated HT29 cells was not affected, suggesting that sugar chains may noy be involved in CD11b/CD18-mediated neutrophil adhesion to HT29 cells.
(5) Treatment of HT29 cells with phosphatidylinositol-specific phospholipase C which cleaves glycosylphosphatidyl inositol (GPI)-anchored protein, did not affect neutrophil adhesion to TNF-α- or histamine-stimulated HT29 cells. In addition, neither RGD peptide nor heparinase treatment of HT29 cells affected neutrophil adhesion to stimulated HT29 cells. These results suggest that GPI-anchored protein, heparin-like glycosaminoglycans and extracellular matrix protein containing RGD sequences are unlikely involved in neutrophil-HT29 cell interactions.
6)腸管上皮細胞の表面を^<125>Iでラベルした後、TNF-αやヒスタミンで刺激し、cell lysateをSDS-PAGEで解析したところ、分子量の31,250,145,85,65kDaの膜表面タンパク質の発現が刺激に応じて増加することがわかった。したがって、これらの分子量の膜タンパク質の1つまたは複数が好中球とHT29との接着に関与する可能性餓死された。 Less
Research Output (6results)