Figure 1: Priming seasonal influenza vaccine with H1-DNA enhances protection against heterologous H1N1 but not against heterosubtypic H5N1 challenge. Mice ( n=10 ) were immunized either 1x with Inflexal (SV), 3x with H1 HA DNA (H1-DNA), 3x with RSV DNA followed by a boost of Inflexal (RSV-DNA/SV), 3x with H1-DNA followed by a boost of Inflexal (H1-DNA/SV) or 4x PBS (PBS). Shown are Kaplan-Meier survival curves (left) and mean bodyweight change (right) graphs following challenge. Mice were challenged with A) H1N1 A/Puerto Rico/8/34 B) H1N1 A/WSN/33 C) H5N1 A/Hong Kong /156/97, Error bars indicate 95% confidence interval (bodyweight).