FIG. 6.

Reduced IgM and IgA antibody response in influenza virus-infected IL-1R1^−/− mice. Groups of mice were infected with 100 PFU influenza virus. To examine antibody responses, mice were bled and BAL fluid was isolated on days 7 (A) and 10 (B and C). Virus-specific antibody levels of the indicated isotypes were measured by ELISA. Values represent the BAL fluid (A and B) and serum (A and C) dilutions at half-maximum absorption (optical density at 405 nm). Lines indicate averages. *, significant differences (Student test).