Skip to main content
. 2018 May 1;8:127. doi: 10.3389/fcimb.2018.00127

Figure 3.

Figure 3

The replication of NS1 R38A/K41A virus is limited in IFN-competent cells during successive passaging. The rescued WT and NS1 mutant viruses of the first passage (F1) were blindly passaged in MDCK cells (A) till the fourth passage (F4). The same volume was used in all infections. The infected MDCK cells of each generation were lysed for western blot analysis. The expression levels of NP and M1 were detected with the respective antibodies (top). GAPDH was probed as the loading control. The relative expression levels of M1 were quantified (below). A549 cells (B) were infected with the rescued F1 WT or NS1 mutant viruses from MDCK cells at the same dose (MOI = 0.001). The harvested F2 viruses were blindly passaged to F4 in A549 cells. Virus from each passage was collected for western blot analysis. NP, M1, and GAPDH were detected (top). The relative expression levels of M1 were quantified (below). Virus titers (C) of F2 to F4 WT and NS1 mutant viruses in A549 cells were measured in MDCK cells by plaque assays.