Assays

A549 cells were infected as described above. At the appropriate time points, 1 mL of cell culture supernatants was harvested and centrifuged at 2,000 rpm for 10 min at 4°C. The clarified supernatants were used for plaque assays to quantify extracellular virions. Cells were washed with ice-cold stringent wash buffer as described above and then detached with 0.05% trypsin-EDTA (Fisher Scientific). Cells were resuspended in 1 mL cDMEM and centrifuged at 300 × g for 5 min at 4°C. Cell pellets were ...