Figure 3

Cigarette smoke (CS) exposure prior to influenza virus infection results in augmented lung inflammation. Mice were exposed to room air (RA) or CS for 3 months and then infected with influenza virus or vehicle control. They were sacrificed and evaluated on day 7 after infection. Representative haematoxylin and eosin stained lung sections from (A) RA-exposed mice, (B) CS-exposed mice, (C) RA-exposed mice with influenza virus infection and (D) CS-exposed mice with influenza virus infection are shown. Scale bar, 100 μm; Original magnification, ×100.