Abstract
Carbon nanotubes have been shown to have the ability to transport therapeutic and detective reagents into cells. However, the rapid advances in new carbon nanotube-based materials and technologies have raised concerns about their safety. Such concerns require a fundamental understanding of the toxicological properties of carbon nanotubes. In particular, the use of carbon nanotubes as drug or probe delivery platforms may depend on the prevention of stimulatory side-effects to the immune system. In this study, we investigated the immunological properties of oxidized water dispersible multi-walled carbon nanotubes (MWCNTs) in healthy BALB/c mice. We injected the MWCNTs subcutaneously, and the immune responses of the mice were monitored over time. We show that the MWCNTs induce complement activation and the production of pro-inflammatory cytokines early after injection of the mice, and that the levels of complement and cytokines return to normal levels over time. With the exception of the lymph nodes, there was no obvious accumulation of MWCNTs observed in the liver, spleen, kidney, or heart. In addition, we did not observe injury in the organs or lymph nodes. Our results indicate that local, subcutaneous administration of MWCNTs induces obvious short-term immunological reactions, which can be eliminated over time.
Acknowledgements
Authors thank National Key Scientific Projects of China (2006CB933204 and 2010CB934002) for the financial support.
Declaration of interest : The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.