Investigation of Immunotoxicity of Copper-based Nanoparticles Using an In Vitro Inhalation Model

Abstract

With a wide range of applications for nanotechnology, there is an increasing risk of nanoparticles (NPs) exposure for workers and the public. While many studies have evaluated the cytotoxicity of copper (Cu) NPs, this research investigated immunotoxicity of Cu NPs using in vitro Streptococcus pneumoniae (S. pneumoniae) infection model. Cu NPs were generated and delivered to human alveolar epithelial type II cells using an in vitro NP inhalation exposure system. Exposure to Cu NPs led to a dose-dependent decrease in cell viability and an increase in ROS production. Cu NPs exposed cells showed a significant increase in total number of S. pneumoniae adhesion. The expression of surface receptors mediating S. pneumoniae infection and cytokines promoting receptor expression were significantly increased in response to Cu NPs exposure. This study provides mechanistic insight into how Cu NPs enhance susceptibility to bacterial infection in human lung cells.