Research Article

Establishment of MDCK Stable Cell Lines Expressing TMPRSS2 and MSPL and Their Applications in Propagating Influenza Vaccine Viruses in Absence of Exogenous Trypsin

Figure 3

Cell fusion induced by cotransfection of protease and influenza HA under acidic conditions. MDCK cells were cotransfected with pCAGGS-TMPRSS2 plus pCAGGS-(Re-5, Re-6, and Re-9) HA and pCAGGS-MSPL plus pCAGGS-(Re-5, Re-6, and Re-9) HA, respectively (a). pCAGGS plus pCAGGS-(Re-5, Re-6, and Re-9) HA supplemented with TPCK-trypsin and pCAGGS plus pCAGGS-(Re-5, Re-6, and Re-9) HA without TPCK-trypsin as control groups (b). See methods for cell treatments. Stained cells were observed under a Leica confocal laser microscope.
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