The adhesion of circulating leukocytes on vascular endothelium is a prerequisite for their emigration to extravascular tissues. The data presented here demonstrate that intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) are constitutively expressed on endothelial cell lines derived from both human brain (HBEC) and umbilical cord veins (HUVEC). Lipopolysaccharide, tumor necrosis factor-alpha or interferon-gamma treatment of both HBEC and HUVEC cell lines up-regulated the expression of these adhesion molecules in a time- and dose-dependent manner. These same pro-inflammatory factors also induced the expression of E-selectin on both HBEC and HUVEC cell cultures. Endothelins (ET-1, ET-2, and ET-3) also had a similar effect on the expression of all three adhesion molecules on HBEC. However, none of the endothelins had any effects on ICAM-1, VCAM-1, or E-selectin expression by HUVEC, despite the concomitant effects of the aforementioned factors on identical cultures. These results indicate that endothelial cells derived from various anatomic locations respond differently to the vasoactive peptide, endothelin, and implicate variations in the role(s) of endothelial cells derived from different anatomic locations in recruitment of blood cells at sites of inflammation.
