At 48 h post‐transfection of the indicated protease plasmids in triplicate, BHK21 cells were incubated with a fluorogenic substrate and wtSPINK6 or loss‐of‐function mutSPINK6 or PBS for 2 h and then applied to fluorescence assay. Data represent mean and SD of triplicated wells in a representative experiment performed three times. **P < 0.01. Student’s t‐test.
At 48 h after co‐transfection of the indicated protease plasmids and H7 or H1 plasmid, BHK21 cells were lysed to examine HA cleavage with WB.
At 48 h after triple transfection of H7, the indicated proteases, and wtSPINK6 or vector, BHK21 cells were lysed for the detection of HA cleavage.
At 48 h after triple transfection of H7, HAT or TMPRSS2, and wtSPINK6 or mutSPINK6, BHK21 cells were lysed for the detection of HA cleavage.
At 48 h after triple transfection of H1, the indicated proteases, and wtSPINK6 or mutSPINK6, BHK21 cells were lysed for the detection of HA cleavage.