Development of IgG response in serum.

Effect of NE adjuvant: Mice were immunized intranasally with HBsAg-NE consisting of 20 μg of HBsAg mixed with 0% to 40% concentrations of NE (A). Significant statistical difference with p value<0.05 was observed between all HBsAg-NE formulations and HBsAg-PBS vaccine. Antigen dose escalation: Mice were immunized intranasally with 1 μg to 40 μg HBsAg mixed with 20% NE (B). A significant statistical difference with p value<0.05 was observed between all 5 μg to 40 μg HBsAg-NE formulations and 1 μg HBsAg-NE vaccine. Serum anti-HBsAg IgG antibody concentrations are presented as mean of endpoint titers in individual sera +/− SEM. * indicates a statistical difference (p value<0.05) in the anti-HBsAg IgG titers. Arrows indicate vaccine administration.