Protection against a lethal H5N1 influenza challenge by intranasal immunization with virus-like particles containing 2009 pandemic H1N1 neuraminidase in mice

► NA VLPs induced protective immunity against challenge with a homologous H5N1 virus. ► VLPs containing the 2009 pandemic H1N1 NA protected mice against a lethal heterologous H5N1 challenge. ► Heterologous protection was afforded even in the absence of high levels of cross-reactive NI titers.