In vitro nanoparticle toxicity to rat alveolar cells and coelomocytes from the earthworm Lumbricus rubellus

Sensitivity of immune cells (coelomocytes) of Lumbricus rubellus earthworms was investigated for exposure to selected nanoparticles, in order to obtain further insight in mechanisms of effects observed after in vivo C-60 exposure. In the in vivo study, tissue damage appeared tooccur without accompanying increased immune responses. Coelomocytes exposed in vitro to C-60 showed no decrease of their cellular viability, but demonstrated a decrease in gene expression of the cytokine-like protein CCF-1, indicating immunosuppression. Experiments with NR8383 rat macrophage cells and tri-block copolymer nanoparticles were used to compare sensitivity and to demonstrate the usefulness of coelomocytes as a test system for nano-immunotoxicity, respectively. Overall, the results imply that sensitivity towards nanoparticles differs between cell types and nanoparticles. Moreover, this study indicates that injuries in absence of an immune response, observed after in vivo C-60 exposure inourearlierwork, are caused by immunosuppression rather than coelomocyte mortality.