Expression of endothelial cell IgG Fc receptors and markers on various cultures.

To determine and compare the expression of endothelial cell IgG Fc receptors (Fc gamma R) and markers on various kinds of cultures.Human breast microvascular endothelial cells (HMVEC), human aortic endothelial cells (HAEC), human umbilical vein endothelial cells (HUVEC) and canine aortic endothelial cells (CAEC) were stimulated with cytokines tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). The binding of anti-Fc gamma receptor (Fc gamma R) type I, II and III antibodies was measured using an enzyme-linked immunosorbent assay (ELISA). The constitutive expression of endothelial cell markers was examined using anti-von Willebrand factor antibodies, Dil-low density lipoprotein (Dil-Ac-LDL) and fluorescein isothiocyanate (FITC)-labeled ulex europaeus agglutinin-1.The binding of anti-Fc gamma R II was significantly increased by the simultaneous stimulation with TNF-alpha and IFN-gamma on all three types of human endothelial cells (ECs), but not on canine endothelial cells. Enhanced Fc gamma R II expression was most significant when human ECs were cultured in endothelial cell basal medium (ECBM). However, the expression of Fc gamma R II on CAECs could not be induced by human cytokines even after they were cultured in ECBM for 3 passages. Endothelial cells also showed diversity for the constitutive expression of classic markers.This study demonstrate that cytokines TNF-alpha and IFN-gamma enhance low-affinity Fc gamma R expression on human endothelial cells in vitro. The results indicate that heterogeneity of endothelial cells exists not only on constitutive expression but also on stimulative expression.