title: Optimization of an air-liquid interface exposure system for assessing toxicity of airborne nanoparticles.
abstract: The use of refined toxicological methods is currently needed for characterizing the risks of airborne nanoparticles (NPs) to human health. To mimic pulmonary exposure, we have developed an air-liquid interface (ALI) exposure system for direct deposition of airborne NPs on to lung cell cultures. Compared to traditional submerged systems, this allows more realistic exposure conditions for characterizing toxicological effects induced by airborne NPs. The purpose of this study was to investigate how the deposition of silver NPs (AgNPs) is affected by different conditions of the ALI system. Additionally, the viability and metabolic activity of A549 cells was studied following AgNP exposure. Particle deposition increased markedly with increasing aerosol flow rate and electrostatic field strength. The highest amount of deposited particles (2.2 μg cm(-2) ) at cell-free conditions following 2 h exposure was observed for the highest flow rate (390 ml min(-1) ) and the strongest electrostatic field (±2 kV). This was estimated corresponding to deposition efficiency of 94%. Cell viability was not affected after 2 h exposure to clean air in the ALI system. Cells exposed to AgNPs (0.45 and 0.74 μg cm(-2) ) showed significantly (P < 0.05) reduced metabolic activities (64 and 46%, respectively). Our study shows that the ALI exposure system can be used for generating conditions that were more realistic for in vitro exposures, which enables improved mechanistic and toxicological studies of NPs in contact with human lung cells.Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.
authors.affiliation: Department of Environmental Science and Analytical Chemistry, Atmospheric Science Unit, Stockholm University, SE-106 91, Stockholm, Sweden.
authors.forename: Siiri
authors.initials: S
authors.lastname: Latvala
authors.affiliation: Division of Surface and Corrosion Science, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Hedberg
authors.affiliation: Department of Biosciences and Nutrition, Unit for Analytical Toxicology, Karolinska Institute, SE-141 83, Huddinge, Sweden.
authors.forename: Lennart
authors.initials: L
authors.lastname: Möller
authors.affiliation: Division of Surface and Corrosion Science, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden.
authors.forename: Inger
authors.initials: I
authors.lastname: Odnevall Wallinder
authors.affiliation: Division of Biochemical Toxicology, Karolinska Institute, Institute of Environmental Medicine, SE-171 77, Stockholm, Sweden.
authors.forename: Hanna L
authors.initials: HL
authors.lastname: Karlsson
authors.affiliation: Department of Environmental Science and Analytical Chemistry, Atmospheric Science Unit, Stockholm University, SE-106 91, Stockholm, Sweden.
authors.forename: Karine
authors.initials: K
authors.lastname: Elihn
mesh_terms: D000072283:A549 Cells; D000336:Aerosols; D000393:Air Pollutants / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity*; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects / Q000032:analysis*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D012834:Silver / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity*; D013499:Surface Properties
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D012834:Silver
keywords: A549; ALI; electrostatic; in vitro; nanoparticles; nanotoxicology; silver