Extracellular entrapment and degradation of single-walled carbon nanotubes

Consol Farrera, Kunal Bhattacharya, Beatrice Lazzaretto, Fernando T. Andón, Kjell Hultenby, Gregg P. Kotchey, Alexander Star, Bengt Fadee

Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden

Neutrophils extrude neutrophil extracellular traps (NETs) consisting of a network of chromatin decorated with antimicrobial proteins to enable non-phagocytic killing of microorganisms. Here, utilizing a model of ex vivo activated human neutrophils, we present evidence of entrapment and degradation of carboxylated single-walled carbon nanotubes (SWCNTs) in NETs. The degradation of SWCNTs was catalyzed by myeloperoxidase (MPO) present in purified NETs and the reaction was facilitated by the addition of H2O2 and NaBr. These results show that SWCNTs can undergo acellular, MPO-mediated biodegradation and imply that the immune system may deploy similar strategies to rid the body of offending microorganisms and engineered nanomaterials.

Link to the paper (link to journal webpage): http://pubs.rsc.org/en/content/articlepdf/2014/nr/c3nr06047k