Nasal administration of vaccines is convenient for the potential stimulation of mucosal and systemic immune protection. Moreover the easy accessibility of the intranasal route renders it optimal for pandemic vaccination. Nanoparticles have been identified as ideal delivery systems and adjuvants for vaccine application. Heterogeneous protocols have been used for animal studies. This complicates the understanding of the formulation influence on the immune response and the comparison of the different nanoparticles approaches developed. Moreover anatomical and immunological differences between rodents and humans provide an additional hurdle in the rational development of nasal nanovaccines. This review will give a comprehensive expertise of the state of the art in nasal nanovaccines in animals and humans focusing on the nanomaterial used.

The intranasal administration of proteins using nanoparticles is a promising approach for several applications, especially for mucosal vaccines. Delivery of protein within the epithelial barrier is a key point to elicit an immune response and nano-carrier has to show no toxicity. The aim of this work was to elucidate the interactions of cationic porous nanoparticles loaded with protein delivery for antigen delivery in the nose. We investigated the loading, the cellular delivery and the epithelial transcytosis of proteins associated to these nanoparticles containing an anionic lipid in their core (NPL). NPL were highly endocytosed by airway epithelial cells and significantly improved the protein delivery into the cell. In vitro transcytosis studies showed that NPL did not modify the in vitro epithelial permeability suggesting no toxicity of these carriers. Moreover protein and NPL did not translocate the epithelial barrier. In vivo studies demonstrated that NPL prolonged the nasal residence time of the protein and no NPL were found beyond the epithelial barrier in vivo, precluding a negative side effect. All together these results establish the NPL as a bio-eliminable and optimal vaccine carrier.