CONTROL OF LYMPHOCYTE ADHESION TO BRAIN AND AORTIC ENDOTHELIUM - ICAM-1, VCAM-1 AND NEGATIVE CHARGE

Lymphocyte adhesion to CNS endothelium is low by comparison with non-C NS endothelium. It has been proposed that this could be due; to the hi gh surface charge of brain endothelium, or a low constitutive expressi on of adhesion molecules. In this study we compared the influence of t hese factors on lymphocyte adhesion to BEC and aortic endothelium (AEC ) in culture. Brain endothelium expresses very low levels of VCAM-1, a nd lower levels of ICAM-1 than aortic endothelium. The negative charge differed between the endothelia, but this had a minimal effect on lym phocyte adhesion. The anionic sites were, however, more stable on brai n endothelium, remaining unchanged after endothelial cell activation w ith cytokines, while redistribution was observed on cytokine-activated aortic endothelium.