Fig 2. Schematic representation of the work-flow employed for DIP production and characterization.

(A) For production of DIPs (DI-244-mScarlet-i), a coculture of 293T-PB2 and MDCK-PB2 cells was cotransfected with plasmids harboring DI-244-mScarlet-i and the wt IAV genomic segments two to eight. Subsequently, trypsin was added for HA activation and supernatants were harvested at the indicated time points. (B) For quantification of DIP production, MDCK-PB2 cells were inoculated with DIP containing supernatants and the number of red cells was counted or the number of foci was determined using focus formation assay. (C) For analysis of antiviral activity of DIPs, MDCK cells were coinfected with IAV wt and DIPs followed by focus formation assay.