ADHESION OF CEREBRAL ENDOTHELIAL-CELLS TO LYMPHOCYTES FROM PATIENTS WITH MULTIPLE-SCLEROSIS

To investigate the factors regulating the entry of lymphocytes into th e brain, we assessed the adhesion in vitro of Cr-51 labelled lymphocyt es from peripheral blood of patients with multiple sclerosis (MS) to h uman cerebral endothelial cells, and evaluated the effect on the adhes ion of endothelium activated by interferon-gamma (IFN-gamma), lipopoly saccharides (LPS), interleukin-1 (IL-1) and tumor necrosis factor (TNF ). Patients with acute relapsing MS during an exacerbation showed sign ificant increase in MNC adherence to cerebral endothelial cells as com pared with controls (p<0.001). MNC adherence to cerebral endothelial c ells activated by IFN-gamma or LPS, was significantly increased as com pared to the controls (p<0.01). MNC adherence to endothelial cells was not blocked by antibodies against the intercellular adhesion molecule -1 (ICAM-1), but was blocked by lymphocyte function-associated antigen -1 (LFA-1). The increased adherence observed in patients with acute re lapsing MS during an exacerbation would modulate the migration of lymp hocytes across the blood-brain barrier (BBB).