Abstract
Tie-1 is an endothelial specific cell surface protein whose biology remains poorly understood. Using an overexpression system in vitro, we examined whether Tie-1 activity in endothelial cells in vitro would elicit a proinflammatory response. We found that when overexpressed in endothelial cells in vitro, Tie-1 is tyrosine-phosphorylated. We also showed that Tie-1 upregulates VCAM-1, E-selectin, and ICAM-1, partly through a p38-dependent mechanism. Interestingly, upregulation of VCAM-1 and E-selectin by Tie-1 is significantly higher in human aortic endothelial cells than in human umbilical vein endothelial cells. Additionally, attachment of cells of monocytic lineage to endothelial cells is also enhanced by Tie-1 expression. Collectively, our data show that Tie-1 has a proinflammatory property and may play a role in the endothelial inflammatory diseases such as atherosclerosis.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
Aorta / cytology
-
Aorta / metabolism
-
Cell Adhesion*
-
E-Selectin / genetics
-
E-Selectin / metabolism*
-
Endothelium, Vascular / cytology
-
Endothelium, Vascular / enzymology*
-
Green Fluorescent Proteins / genetics
-
Humans
-
Intercellular Adhesion Molecule-1 / genetics
-
Intercellular Adhesion Molecule-1 / metabolism*
-
Mice
-
Monocytes / physiology
-
Phosphorylation
-
Receptor, TIE-1 / genetics
-
Receptor, TIE-1 / metabolism*
-
Tyrosine / metabolism
-
Up-Regulation
-
Vascular Cell Adhesion Molecule-1 / genetics
-
Vascular Cell Adhesion Molecule-1 / metabolism*
-
p38 Mitogen-Activated Protein Kinases / genetics
-
p38 Mitogen-Activated Protein Kinases / metabolism
Substances
-
E-Selectin
-
Vascular Cell Adhesion Molecule-1
-
Intercellular Adhesion Molecule-1
-
Green Fluorescent Proteins
-
Tyrosine
-
Receptor, TIE-1
-
p38 Mitogen-Activated Protein Kinases