Ad4-H5-Vtn vector design

<p>The H5HA native coding sequence, with the polybasic domain removed (B), was derived from A/Vietnam/1194/2004 influenza virus and inserted into the Ad4 virus E3 gene region. The Ad4 virus E3 24.8K, E3 6.3K and E3 29.7K genes were deleted to accommodate the HA transgene and the splice acceptor site of E3 24.8K was retained to drive expression of the HA transgene. The E3A polyadenylation signal sequence, derived from Ad5, was placed downstream of the HA coding sequence. The use of a shuttle plasmid encoding the H5HA sequence and the Ad4 plasmid to obtain the final vaccine product is described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031177#s2" target="_blank">Materials and Methods</a>.</p