FIG. 4.

Comparison of tissue virus titers in WT (A), STAT1−/− (B), and IFNαR−/− (C) mice at different days after i.n. inoculation with WSN virus. (A and B) Eight to 10 WT (A) or STAT1−/− (B) mice were infected i.n. with 1,000 PFU of WSN virus, and viral titers in the indicated tissues at days 3 (■) and 6 (□) p.i. were determined by plaque assay in MDCK cells. Results from two experiments are expressed as PFU/gram of tissue. (C) Six IFNαR−/− mice were infected i.n. with 1,000 PFU of WSN virus, and viral titers at days 4 (■) and 8 (□) p.i. were determined by plaque assay in MDCK cells. Results are expressed as PFU/gram of tissue.