Pathogenicity of modified bat influenza virus with different M genes and its reassortment potential with swine influenza A virus Yang, Jianmei and Lee, Jinhwa and Ma, Jingjiao and Lang, Yuekun and Nietfeld, Jerome and Li, Yuhao and Duff, Michael and Li, Yonghai and Yang, Yuju and Liu, Haixia and Zhou, Bin and Wentworth, David E and Richt, Juergen A and Li, Zejun and Ma, Wenjun,, 98, 577-584 (2017), doi = https://doi.org/10.1099/jgv.0.000715, publicationName = Microbiology Society, issn = 0022-1317, abstract= In our previous studies, the reassortant virus containing only the PR8 H1N1 matrix (M) gene in the background of the modified bat influenza Bat09 : mH1mN1 virus could be generated. However, whether M genes from other origins can be rescued in the background of the Bat09 : mH1mN1 virus and whether the resulting novel reassortant virus is virulent remain unknown. Herein, two reassortant viruses were generated in the background of the Bat09 : mH1mN1 virus containing either a North American or a Eurasian swine influenza virus M gene. These two reassortant viruses and the reassortant virus with PR8 M as well as the control Bat09 : mH1mN1 virus replicated efficiently in cultured cells, while the reassortant virus with PR8 M grew to a higher titre than the other three viruses in tested cells. Mouse studies showed that reassortant viruses with either North American or Eurasian swine influenza virus M gene did not enhance virulence, whereas the reassortant virus with PR8 M gene displayed higher pathogenicity when compared to the Bat09 : mH1mN1 virus. This is most likely due to the fact that the PR8 H1N1 virus is a mouse-adapted virus. Furthermore, reassortment potential between the Bat09 : mH1mN1 virus and an H3N2 swine influenza virus (A/swine/Texas/4199-2/1998) was investigated using co-infection of Madin–Darby canine kidney cells, but no reassortant viruses were detected. Taken together, our results indicate that the modified bat influenza virus is most likely incapable of reassortment with influenza A viruses with in vitro co-infection experiments, although reassortant viruses with different M genes can be generated by reverse genetics., language=, type=