FIG. 3.

Inhibition of virus replication in MDCK cells. (A) Cells were infected with the indicated viruses at an MOI of 0.1 and treated with drug or 1% DMSO (shown as 0 μM) starting 1 h postinfection. The DMSO concentration for all drug-treated cultures was 1%. After incubation for 48 h, the supernatants were collected and analyzed for TCID₅₀ by the method of Reed and Muench (57). (B) Protein expression in infected cells. In the left panel, MDCK cells were infected with A/HK/19/68 at an MOI of 0.1 for 24 h, in the presence or absence of the indicated compounds at 50 μM. The cells were labeled with [³⁵S]methionine and [³⁵S]cysteine for the final hour of infection. Cell lysates were analyzed by SDS-PAGE and visualized by using a phosphorimager. In the right panel, infected cells were analyzed for total NP protein expression by Western blotting. Blots were also probed for β-tubulin and β-actin as loading controls.