Influenza viruses are among the most significant pathogens of humans and animals. Reverse genetics allows for the study of molecular attributes that modulate virus host range, virulence and transmission. The most common reverse genetics methods use bi-directional vectors containing a host RNA polymerase (pol) I promoter to produce virus-like RNAs and a host RNA pol II promoter to direct the synthesis of viral proteins. Given the species-dependency of the pol I promoter and virus-host interactions that influence replication of animal-origin influenza viruses in human-derived cells, we explored the potential of using the swine RNA pol I promoter (spol1) in a bi-directional vector for rescuing type A and B influenza viruses (IAV and IBV, respectively) in swine and human cells. The spol1-based bi-directional plasmid vector led to efficient rescue of IAVs of different origins (human, swine, and avian) as well as IBV in both swine- and human-origin tissue culture cells. In addition, virus rescue was successful using a recombinant bacmid containing all eight segments of a swine origin IAV. In conclusion, the spol1-based reverse genetics system is a new platform to study influenza viruses and produce swine influenza vaccines with increased transfection efficiency.

流感病毒是人类和动物最重要的病原体之一。反向遗传学可以研究调节病毒宿主范围、毒力和传播的分子属性。最常见的反向遗传学方法使用含有宿主 RNA 聚合酶 (pol) I 启动子的双向载体来产生病毒样 RNA，以及宿主 RNA pol II 启动子来指导病毒蛋白的合成。鉴于 pol I 启动子的物种依赖性以及影响动物源流感病毒在人源细胞中复制的病毒-宿主相互作用，我们探索了在双向使用猪 RNA pol I 启动子 ( spol1 ) 的潜力。用于拯救猪和人细胞中的 A 型和 B 型流感病毒（分别为 IAV 和 IBV）的载体。基于spol1的双向质粒载体可有效拯救不同来源（人、猪和禽）的 IAV 以及猪和人来源组织培养细胞中的 IBV。此外，使用含有猪源 IAV 全部八个片段的重组杆粒成功拯救了病毒。总之，基于spol1的反向遗传学系统是研究流感病毒和生产具有更高转染效率的猪流感疫苗的新平台。