Immune responses of BALB/c mice to subcutaneously injected multi-walled carbon nanotubes

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.

Macrophages participate in local and systemic inflammation induced by amorphous silica nanoparticles through intratracheal instillation

“…A previous study about carbon nanotubes found that 2 days following injection the cytokines changed significantly, whereas most returned to approximately normal levels after 7 days. 23 The changes of serum cytokine level in this study suggested that the inflammatory reaction was actively induced by the SiNPs.…”

“…A previous study indicated that carbon nanoparticles accumulated in the lymph nodes over 90 days following subcutaneous injection. 23 Lymph nodes have an important function in the immune system -they filter foreign particles and eliminate them through the macrophages -and also play a role in immune response. Herein, the number of macrophages present in the lymph nodes was increased in the SiNP-treated group, despite there being no obvious SiNP accumulation.…”

Safe Clinical Use of Carbon Nanotubes as Innovative Biomaterials

“…Accordingly, it was concluded that CNTs do not affect the immune system. 326 Of course, special caution should be exercised when using CNTs in particular sites, for example, the heart and lung. Their use in the ovary and uterus, which lie within the abdominal cavity, should also be avoided.…”

Immunomodulation of Nanoparticles in Nanomedicine Applications

“…Subcutaneous administration of MWCNTs with total dose of 1.0 mg for two s.c injections in BALB/c mice induced acute immunological reactions for 1 week (activation of complement and increased proinflammatory cytokines). However, the accumulation of MWCNTs and injury was not observed in spleen [24]. MWCNTs injected intravenously activated Th2 immune response by elevating Th2 cytokines and increasing number of CD4 + and CD8 + T cell in the spleen [23].…”