E-Selectin expression on human brain microvascular endothelial cells

E-Selectin is an endothelial adhesion molecule involved in binding and targeting of neutrophils. Little is known of its expression in the brain. We examined the expression of E-selectin on cultured human brain microvascular endothelial cells (HBMEC). There was no basal expression of E-selectin on HBMEC but with Il-1b, tumor necrosis factor (TNF), or lipopolysaccharide (LPS) stimulation there was surface expression at 4 h. The expression was quantitatively less than on cultured human umbilical vein endothelial cells (HUVEC). The cytokine-induced upregulation was partially inhibited with the glutathione donor, N-acetylcysteine (NAC), the free radical scavenger, dimethylthiourea (DMTU; 15 mM) and dexamethasone (1 μM). Allopurinol (100 μM) had no effect. TNF activated nuclear factor κB (NFκB) in HBMEC. This activation could be attenuated by prior treatment with NAC and dexamethasone. Thiol donors and corticosteroids could play a role in inhibiting potentially deleterious neutrophil-endothelial interactions in inflammatory conditions involving the brain.