Immunization onto shaved skin with a bacterial enterotoxin adjuvant protects mice against Respiratory Syncytial Virus (RSV)

This study evaluated the potential of the skin as a non invasive route for RSV vaccination using two G protein-derived molecules, G2Na and G5 in mice. G2Na contains T and B-cell epitopes whether G5 is a pure B-cell epitope. In contrast to G5, G2Na coadministered with CT three times at 1 month interval onto 1cm of square area shaved skin, elicited a consistent serum anti-G2Na and anti-CT IgG response. The anti-G2Na IgG response was dominated by IgG1 isotype, an indirect marker of a Th2 type of response. Dramatic reduction and decrease of RSV titers in lung tissues and in the nasal tract, respectively, following intranasal virus challenge revealed biological relevance of the transcutaneous immunization in the context of RSV vaccine. These results suggest that the transcutaneous route may offer a promising potential for novel RSV vaccine strategy, simple, painless and economical.