Figure 2

Detection of HA cleavage. All mutant viruses infected CEF at an MOI of 1 for 72 h. Samples were taken at 12-h intervals and subjected to Western blot analysis.
Detection of HA cleavage. All mutant viruses infected CEF at an MOI of 1 for 72 h. Samples were taken at 12-h intervals and subjected to Western blot analysis.