Truncated influenza neuraminidases and methods of use thereof

A modified influenza virus subtype 2 neuraminidase molecule is provided that lacks all or substantially all stem regions that when expressed in a host cell forms an active soluble tetrameric neuraminidase, and vaccine compositions comprising the tetrameric neuraminidase or a nucleic acid encoding the modified monomeric influenza virus subtype 2 neuraminidase molecule that forms a tetrameric NA when expressed in a cell. Also provided are methods of using the vaccine compositions to vaccinate a subject against an influenza virus or immunize a subject against an influenza virus. 提供了缺少全部或基本上全部茎区的、当在宿主细胞中表达时形成活性可溶性四聚体神经氨酸酶的经修饰的流感病毒亚型2神经氨酸酶分子，以及包含所述四聚体神经氨酸酶或编码当在细胞中表达时形成四聚体NA的所述经修饰的单体流感病毒亚型2神经氨酸酶分子的核酸的疫苗组合物。还提供了使用所述疫苗组合物以针对流感病毒对受试者进行疫苗接种或使受试者对流感病毒免疫的方法。