title: Amorphous silica nanoparticles promote monocyte adhesion to human endothelial cells: size-dependent effect.
abstract: There is evidence that nanoparticles can induce endothelial dysfunction. Here, the effect of monodisperse amorphous silica nanoparticles (SiO(2)-NPs) of different diameters on endothelial cells function is examined. Human endothelial cell line (EA.hy926) or primary human pulmonary artery endothelial cells (hPAEC) are seeded in inserts introduced or not above triple cell co-cultures (pneumocytes, macrophages, and mast cells). Endothelial cells are incubated with SiO(2)-NPs at non-cytotoxic concentrations for 12 h. A significant increase (up to 2-fold) in human monocytes adhesion to endothelial cells is observed for 18 and 54 nm particles. Exposure to SiO(2)-NPs induces protein expression of adhesion molecules (ICAM-1 and VCAM-1) as well as significant up-regulation in mRNA expression of ICAM-1 in both endothelial cell types. Experiments performed with fluorescent-labelled monodisperse amorphous SiO(2)-NPs of similar size evidence nanoparticle uptake into the cytoplasm of endothelial cells. It is concluded that exposure of human endothelial cells to amorphous silica nanoparticles enhances their adhesive properties. This process is modified by the size of the nanoparticle and the presence of other co-cultured cells.
authors.affiliation: Department of Public Health, Center for Environment and Health, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Dorota
authors.initials: D
authors.lastname: Napierska
authors.forename: Rozenn
authors.initials: R
authors.lastname: Quarck
authors.forename: Leen C J
authors.initials: LC
authors.lastname: Thomassen
authors.forename: Dominique
authors.initials: D
authors.lastname: Lison
authors.forename: Johan A
authors.initials: JA
authors.lastname: Martens
authors.forename: Marion
authors.initials: M
authors.lastname: Delcroix
authors.forename: Benoit
authors.initials: B
authors.lastname: Nemery
authors.forename: Peter H
authors.initials: PH
authors.lastname: Hoet
mesh_terms: D002448:Cell Adhesion / Q000502:physiology; D002460:Cell Line; D018920:Coculture Techniques / Q000379:methods*; D042783:Endothelial Cells / Q000166:cytology*; D006801:Humans; D009000:Monocytes / Q000166:cytology*; D053758:Nanoparticles / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D012822:Silicon Dioxide