title: Induction of cell death by TiO2 nanoparticles: studies on a human monoblastoid cell line.
abstract: The cellular responses to degradation products from titanium (Ti) implants are important indicators for the biocompatibility of these widely used implantable medical devices. The potential toxicity of nanoparticulate matter released from implants has been scarcely studied. The aim of this study was to investigate the potential of TiO2 nanoparticles to induce modifications characteristic for death by apoptosis and/or necrosis in U937 human monoblastoid cells. Suspensions of TiO2 nanoparticles with a diameter <100nm were prepared in RPMI cell culture medium at concentrations that covered a range (0.005-4mg/ml) corresponding to concentrations found in blood, plasma, or in tissues surrounding Ti implants. The cells were exposed to the nanoparticulate suspensions for 24 and 48h and the responses were evaluated by flow cytometry and transmission electron microscopy. TiO2 nanoparticles induced both apoptotic and necrotic modifications in U937 cells.
authors.affiliation: Department of Clinical Dentistry--Biomaterials, Faculty of Medicine and Dentistry, University of Bergen, Aarstadveien 17, 5009 Bergen, Norway.
authors.forename: Carmen I
authors.initials: CI
authors.lastname: Vamanu
authors.forename: Mihaela R
authors.initials: MR
authors.lastname: Cimpan
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Høl
authors.forename: Steinar
authors.initials: S
authors.lastname: Sørnes
authors.forename: Stein A
authors.initials: SA
authors.lastname: Lie
authors.forename: Nils R
authors.initials: NR
authors.lastname: Gjerdet
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000008:administration & dosage / Q000633:toxicity*; D009336:Necrosis / Q000209:etiology; D010316:Particle Size; D019736:Prostheses and Implants / Q000009:adverse effects; D013997:Time Factors; D014025:Titanium / Q000008:administration & dosage / Q000633:toxicity*; D020298:U937 Cells
chemical_list: D001672:Biocompatible Materials; C009495:titanium dioxide; D014025:Titanium