Open AccessEstablishment of an in vivo simulating co‐culture assay platform for genotoxicity of multi‐walled carbon nanotubes
Author(s) -
Fukai Emi,
Sato Haruna,
Watanabe Masatoshi,
Nakae Dai,
Totsuka Yukari
Publication year - 2018
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.13534
Subject(s) - genotoxicity , in vivo , chemistry , in vitro , carbon nanotube , cell culture , reactive oxygen species , immune system , biophysics , microbiology and biotechnology , nanotechnology , toxicity , biology , biochemistry , immunology , materials science , genetics , organic chemistry
Engineered nanomaterials ( ENM ) are now used in a wide variety of fields, and, thus, their safety should urgently be assessed and secured. It has been suggested that inflammatory responses via the phagocytosis of ENM by macrophages is a key mechanism for their genotoxicity. The present study was conducted to establish a mechanism‐based assay to evaluate the genotoxicity of ENM under conditions simulating an in vivo situation, featuring a co‐culture system of murine lung resident cells ( GDL 1) and immune cells ( RAW 264.7). GDL 1 were cultured with or without RAW 264.7, exposed to a multi‐walled carbon nanotube ( MWCNT ), and then analyzed for mutagenicity and underlying mechanisms. Mutation frequencies induced in GDL 1 by the MWCNT were significantly greater with the co‐existence of RAW 264.7 than in its absence. Mutation spectra observed in GDL 1 co‐cultured with RAW 264.7 were different from those seen in GDL 1 cultured alone, but similar to those observed in the lungs of mice exposed to the MWCNT in vivo. Inflammatory cytokines, such as IL ‐1β and TNF ‐α, were produced from RAW 264.7 cells treated with the MWCNT . The generation of reactive oxygen species and the formation of 8‐oxodeoxyguanosine in GDL 1 exposed to the MWCNT were greater in the co‐culture conditions than in the single culture conditions. Based on these findings, it is indicated that inflammatory responses are involved in the genotoxicity of MWCNT , and that the presently established, novel in vitro assay featuring a co‐culture system of tissue resident cells with immune cells is suitable to evaluate the genotoxicity of ENM .