title: Size-dependent cytotoxic effects of amorphous silica nanoparticles on Langerhans cells.
abstract: Amorphous silica nanoparticles (nSPs), are widely used in medicines, cosmetics and food. However, due to their reduced particle size they are suspected to pose new risks induced by changes in biological reactivity and kinetics, which differ from those of bulk materials. In a previous study, we showed that silica particles with a diameter of 70 nm penetrated the stratum corneum (SC) of mouse skin and were taken up by living cells such as keratinocytes and Langerhans cells. To clarify the relationship between particle size, distribution and cellular response, we have evaluated size-dependent intracellular localization and cytotoxicity of silica particles, using the mouse epidermal Langerhans cell line XS52. On treatment with silica particles of diameters 70, 300, and 1000 nm, cellular uptake and cytotoxicity increased with reduction in particle size. These results suggest that smaller sized silica particles induced greater cytotoxicity against Langerhans cells, which was correlated with the quantity of particle uptake into the cells.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nabeshi
authors.forename: T
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: K
authors.initials: K
authors.lastname: Matsuyama
authors.forename: Y
authors.initials: Y
authors.lastname: Nakazato
authors.forename: A
authors.initials: A
authors.lastname: Arimori
authors.forename: M
authors.initials: M
authors.lastname: Isobe
authors.forename: S
authors.initials: S
authors.lastname: Tochigi
authors.forename: S
authors.initials: S
authors.lastname: Kondoh
authors.forename: T
authors.initials: T
authors.lastname: Hirai
authors.forename: T
authors.initials: T
authors.lastname: Akase
authors.forename: T
authors.initials: T
authors.lastname: Yamashita
authors.forename: K
authors.initials: K
authors.lastname: Yamashita
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: K
authors.initials: K
authors.lastname: Nagano
authors.forename: Y
authors.initials: Y
authors.lastname: Abe
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshioka
authors.forename: H
authors.initials: H
authors.lastname: Kamada
authors.forename: T
authors.initials: T
authors.lastname: Imazawa
authors.forename: N
authors.initials: N
authors.lastname: Itoh
authors.forename: S
authors.initials: S
authors.lastname: Tsunoda
authors.forename: Y
authors.initials: Y
authors.lastname: Tsutsumi
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D015603:Keratinocytes / Q000187:drug effects; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D007801:Langerhans Cells / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D051379:Mice; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000633:toxicity*; D010316:Particle Size; D012822:Silicon Dioxide / Q000633:toxicity*; D013936:Thymidine / Q000378:metabolism
chemical_list: D012822:Silicon Dioxide; D007770:L-Lactate Dehydrogenase; D013936:Thymidine