FIG. 8.

Inhibition of IDO during the primary immune response to influenza virus infections decreases histopathology associated with a lethal influenza challenge independent of virus clearance. X31 primed mice, which were treated with 1MT or vehicle control were rested 28 days prior to challenge with PR8. Representative lung sections following PR8 challenge are shown for IMT and control mice. Average gross pathology scores±SEM are shown. A histological score for each lung was determined according to the following criteria: 0=no lung abnormality; 1=<10% of airways inflamed; 2=10%–30% of airways inflamed; 3=30%–50% of airways inflamed, and 4=>50% of airways inflamed. Scale bars=500 μm.