Amorphous nanosilica particles induce ROS generation in Langerhans cells.

Generation of total intracellular reactive oxygen species (ROS) was measured in XS52 cells, a Langerhans cell-like line, treated with different sized amorphous silica particles. The results suggested that exposure to amorphous nanosilica particles (nSPs) with a particle size of 70 nm induced a higher level of ROS generation than did exposure to micron-sized amorphous silica particles. This finding means that it is essential to examine the biological effects of ROS generated after exposure to nSPs, which will provide useful information for hazard identification as well as the design of safer nanomaterials.