抗原エピトープ封入油状ナノキャリアを用いた 花粉症経皮ワクチンの開発

抄録

In recent years, pollinosis immunotherapy has been attracting much attention, however, the administration methods of vaccine drugs have been limited to the subcutaneous injection or the sublingual administration. In this study, we developed a transdermal vaccine administration strategy for the simple and non–invasive pollinosis immunotherapy. For the transdermal antigen delivery, the presence of stratum corneum, the hydrophobic outermost layer of the skin, is an obstacle. Another problem with current pollinosis immunotherapy is side effects of using the whole allergen molecules. To overcome these issues, we applied a solid–in–oil (S/O) nanodispersion, which is composed of hydrophilic antigen molecules coated with hydrophobic surfactants, and enables transdermal penetration of the antigen molecules into the skin. In addition, we introduced a T cell epitope peptide derived from the cedar pollen allergen (PepA : SMKVTVAFNQFGP), which had shown lower risks of the side effects. We succeeded in preparing an S/O nanodispersion containing PepA. The oil–based S/O system enhanced the skin penetration of the PepA. Antigen specific IgE levels in the murine models were significantly reduced by the S/O administration. Activations of the type–1 helper T and regulatory T cells were also confirmed, which indicates the effectiveness of the pollinosis immunotherapy using the S/O vaccine system.