The Chorioallantoic Membrane Assay (CAM-Assay) as an in vivo model analysing the remaining of therapeutically applied nanoparticles

Nanoparticles are regarded as a promising therapeutic anti-cancer agent in treatment of head and neck tumours. On the way to clinical use the evaluation of toxicity is a central obstacle. However, animal experiments are associated with high costs and bureaucratic barriers. The Chorionallantoic Membrane-Assay (CAM-Assay) may offer an attractive alternative with low costs, no necessity of an ethics committee approval for animal experimentation and simple experimental conditions.

In order to analyse a possible organ-specific accumulation of therapeutically applied nanoparticles, we injected ZnO@SiO₂ nanoparticles.

Fertilized hen's eggs were incubated and opened during the experiment, providing access to the chorionallantoic membrane, which could be seen as an equivalent of mammalian placenta.

On day 10 of incubation, ZnO@SiO₂ nanoparticles (FITC-labelled) or NaCl (control) were injected. After 7h and 24h we fixated CAM, brain, heart, liver and kidney. The samples were histologically processed afterwards and appraised with confocal microscopy.

We could detect accumulation of ZnO@SiO₂ nanoparticles in the heart, liver and kidney after 7h and 24h, respectively, while examination of brain and CAM showed no nanoparticular accumulation. Kidney and liver showed frequent accumulation while the heart only showed single particles. Our data suggests that accumulation of nanoparticles occurs mainly in organs with high blood flow. However, the brain appears to be sufficiently protected, which may be due to mechanisms such as the blood-brain-barrier.

Our experiments demonstrate that the CAM-Assay is a promising model for the analysis of nanoparticular agent's accumulation, possible even for those therapeutically applied.

Publication History

Publication Date:
23 April 2019 (online)