Towards elucidating the effects of purified MWCNTs on human lung epithelial cells

Abstract

Toxicity of engineered nanomaterials is associated with their inherent properties, both physical and chemical. Recent studies have shown that exposure to multi-walled carbon nanotubes (MWCNTs) promotes tumors and tumor-associated pathologies and lead to carcinogenesis in model in vivo systems. Herein, we examined the potential of purified MWCNTs used at occupationally relevant exposure doses for particles not otherwise regulated to affect human lung epithelial cells. The uptake of the purified MWCNTs was evaluated using fluorescence activated cell sorting (FACS), while the effects on cell fate were assessed using a 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium salt colorimetric assay, cell cycle and nanoindentation. Our results showed that exposure to MWCNTs reduced cell metabolic activity and induced cell cycle arrest. Our analysis further emphasized that the MWCNTs-induced cellular fate result from multiple types of interactions that could be analyzed by means of intracellular biomechanical changes and are pivotal in understanding the underlying MWCNT-induced cell transformation.