title: A comparative study of different in vitro lung cell culture systems to assess the most beneficial tool for screening the potential adverse effects of carbon nanotubes.
abstract: To determine the potential inhalatory risk posed by carbon nanotubes (CNTs), a tier-based approach beginning with an in vitro assessment must be adopted. The purpose of this study therefore was to compare 4 commonly used in vitro systems of the human lung (human blood monocyte-derived macrophages [MDM] and monocyte-derived dendritic cells [MDDC], 16HBE14o- epithelial cells, and a sophisticated triple cell co-culture model [TCC-C]) via assessment of the biological impact of different CNTs (single-walled CNTs [SWCNTs] and multiwalled CNTs [MWCNTs]) over 24h. No significant cytotoxicity was observed with any of the cell types tested, although a significant (p < .05), dose-dependent increase in tumor necrosis factor (TNF)-α following SWCNT and MWCNT exposure at concentrations up to 0.02mg/ml to MDM, MDDC, and the TCC-C was found. The concentration of TNF-α released by the MDM and MDDC was significantly higher (p < .05) than the TCC-C. Significant increases (p < .05) in interleukin (IL)-8 were also found for both 16HBE14o- epithelial cells and the TCC-C after SWCNTs and MWCNTs exposure up to 0.02mg/ml. The TCC-C, however, elicited a significantly (p < .05) higher IL-8 release than the epithelial cells. The oxidative potential of both SWCNTs and MWCNTs (0.005-0.02mg/ml) measured by reduced glutathione (GSH) content showed a significant difference (p < .05) between each monoculture and the TCC-C. It was concluded that because only the co-culture system could assess each endpoint adequately, that, in comparison with monoculture systems, multicellular systems that take into consideration important cell type-to-cell type interactions could be used as predictive in vitro screening tools for determining the potential deleterious effects associated with CNTs.
authors.affiliation: * Bio-Nanomaterials, Adolphe Merkle Institute, University of Fribourg, 1723 Fribourg, Switzerland;
authors.forename: Martin J D
authors.initials: MJ
authors.lastname: Clift
authors.forename: Carola
authors.initials: C
authors.lastname: Endes
authors.forename: Dimitri
authors.initials: D
authors.lastname: Vanhecke
authors.forename: Peter
authors.initials: P
authors.lastname: Wick
authors.forename: Peter
authors.initials: P
authors.lastname: Gehr
authors.forename: Roel P F
authors.initials: RP
authors.lastname: Schins
authors.forename: Alke
authors.initials: A
authors.lastname: Petri-Fink
authors.forename: Barbara
authors.initials: B
authors.lastname: Rothen-Rutishauser
mesh_terms: D001681:Biological Assay; D015415:Biomarkers / Q000097:blood; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D019570:Inhalation Exposure / Q000009:adverse effects; D016209:Interleukin-8 / Q000378:metabolism; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D037742:Nanotubes, Carbon / Q000633:toxicity*; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D014116:Toxicology / Q000379:methods*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015415:Biomarkers; C508606:CXCL8 protein, human; D018836:Inflammation Mediators; D016209:Interleukin-8; D037742:Nanotubes, Carbon; D014409:Tumor Necrosis Factor-alpha; D005978:Glutathione
keywords: carbon nanotubes; in vitro lung systems; inflammation; nanotoxicology; oxidative stress; risk assessment.