Nanoparticle (NP) uptake by type I alveolar epithelial cells and their oxidant stress response

Mammalian cells take up nanoparticles (NPs) and some NPs increase ROS. We used imaging and measure ROS in parallel to evaluate NP-cell interactions with type I-like alveolar epithelial cells exposed to NPs at 1.2 mu g/cm(2). Titanium dioxide (TiO(2)), gold (Au), silver (Ag), and manganese (Mn) were internalized by R3-1 cells; copper (Cu) NPs were observed at the cell surface only. TiO(2) and Au did not increase cell death but Mn and Cu did, with surviving cells recovering after initial Cu exposure. Ag NPs caused 80% of R3-1 cells to lift off the slides within 1 h. Amplex Red was used to report H(2)O(2) production after exposure to 0.4 mu g/cm(2) TiO(2), Au, Cu, Mn and Ag. TiO(2), Au, and Ag caused no significant increase in H(2)O(2) while Cu and Mn increased H(2)O(2). NPs that give up electrons, increase ROS production and cause cell death in R3-1 cells.