Cytoplasmic Domain of Intercellular Adhesion Molecule-1(ICAM-1)is Important for the ICAM-1 Mediated Membrane Projection of Endothelial Cells.
- Author:
Geom Seog SEO
1
;
Minkyu CHOI
;
Hyun Mee OH
;
Moo Hyung LEE
;
Kang Min LEE
;
Yong Ho NAH
;
Chang Duk JUN
Author Information
1. Digestive Disease Research University, Wonkwang University School of Medicine, Korea.
- Publication Type:Original Article
- Keywords:
ICAM-1;
SDF-1alpha;
LFA-1;
T lymphocyte;
alpha-actinin;
Membrane projection
- MeSH:
Actin Cytoskeleton;
Actinin;
Actins;
Animals;
Cell Membrane;
Chemokine CXCL12;
COS Cells;
Cytoplasm*;
Endothelial Cells*;
Hand;
Humans;
Intercellular Adhesion Molecule-1*;
Leukocytes;
Lymphocyte Function-Associated Antigen-1;
Lymphocytes;
Membranes*;
Microscopy, Confocal
- From:Korean Journal of Anatomy
2005;38(1):11-19
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Intercellular adhesion molecule-1 (ICAM-1)has been shown to enhance leukocyte adhesion, thereby inducing migration through blood endothelial cells. However, the molecular event during the process of adhesion is largely unknown. To examine the role of ICAM-1 cytoplasmic domain in SDF-1 alpha-induced T lymphocyte migration and adhesion, mutant human ICAM-1 molecules were expressed in COS-7 cell line. COS-7 cells expressing ICAM-1_GFP mutant without alpha-actinin revealed no association with the actin cytoskeleton, while wild-type ICAM-showed clear association with the actin, as observed by confocal microscopy, suggesting that actinin binding motif in the cytoplasmic domain of ICAM-1 is important for the proper localization of ICAM-1 on the cell membrane. However, based on adhesion assay, we found that the cytoplasmic domain of ICAM-1 is not essential for the binding of lymphocytes which were activated by SDF-1alpha. On the other hand, ICAM-1-mediated receptor-ligand clustering event was significantly inhibited in the cells expressing ICAM-1 mutants without alpha-actinin or whole cytoplasmic domain. Taken together, these results suggest that ICAM-1 cytoplasmic domain is not essential for the adhesion but important for the ligand-receptor-mediated membrane projection of endothelial cells before trans-endothelial migration of lymphocytes.
