In vitro modulation of adhesion molecules, adhesion phenomena, and fluid phase endocytosis on human umbilical vein endothelial cells and brain-derived microvascular endothelium by IFN-beta 1a

Administration of interferon-beta (IFN-beta) in multiple sclerosis (MS) pat ients provides clinical benefits, although its mechanism(s) of action are n ot completely understood. We addressed the issue of whether concentrations of IFN-beta 1a close to those reached in the serum of treated MS patients c ould modulate either adhesion molecules or adhesion of peripheral blood mon onuclear cells (PBMC) as well as fluid phase endocytosis (FPE) in human umb ilical vein endothelial cells (HUVEC) and in brain-derived microvascular en dothelial cells (HBMEC). Adhesion was assessed by flow cytometry, and FPE w as evaluated by peroxidase uptake. In our study, 200 U/ml IFN-beta 1a induc ed a reduction in adhesion of PBMC to HUVEC. The information reported herei n may contribute to further elucidating some of the mechanisms of action of IFN-beta on vascular endothelium.