Upregulation of intercellular adhesion molecule-1 expression on human endothelial cells by tumour necrosis factor-alpha in an in vitro model of the blood-brain

Adhesion molecules on the endothelial surface of the blood-brain barrier (B BB) play an important role in the pathogenesis of many encephalopathies, in cluding multiple sclerosis (MS) and cerebral malaria; (CM). The expression of four surface molecules of relevance to MS and CM on the immortalized hum an umbilical vein endothelial cell line, ECV304, was investigated using imm unofluorescence flow cytometry. We found that ECV304 cells express intercel lular adhesion molecule-1 (ICAM-1) and low levels of CD36, but not vascular cell adhesion molecule-1 (VCAM-1) or E-selectin. This expression pattern w as unaltered on ECV304 cells which were co-cultured with C6 glioma cells; c onditions under which the endothelial cells display enhanced barrier format ion. Tumour necrosis factor-alpha (TNF-alpha), which is elevated in MS and CM, decreased the integrity of the barrier in co-cultured endothelial cells and upregulated the expression of ICAM-1 nine-fold. The significance of el evated ICAM-1 expression in relation to the binding of parasitised erythroc ytes at the BBB in CM is discussed. (C) 1999 Elsevier Science B.V. All righ ts reserved.