(A) Drug treatment regimen with anti-NK antibody. Arrows denote days on which anti-NK or normal rabbit serum (NRS) were i.p. injected, drug injections were performed, and 7,000 PFU SeV was intranasally inoculated in 5 μL PBS. (B) Peripheral NK cell absolute numbers at 16 d.a.d.s. (C-E) Bioluminescence in the nasopharynx (C), trachea (D), and lungs (E). (F) Percent change in starting weight. Groups include PBS (black bars and circles), Dexa + Cy (light blue bars and triangles), Dexa + Cy + anti-NK (orange bars and octagons), and Dexa + Cy + NRS (green bars and stars). The data shown are averages of 5 mice per group. In all graphs, error bars represent the standard deviation. d.p.i., days postinfection; d.a.d.s., days after drug started. *** P < 0.001.