IL10 and influenza: Consistent with these observations, a significant increase in pulmonary viral load was observed at 4 dpi in WT(DCB/Flu) mice compared to WT(Air/Flu) mice (Fig. 5c), whereas, smaller areas of the lungs were infected with influenza (Fig. 5b) as evidenced by immunohistochemistry for influenza virus and a significant decrease in peak pulmonary viral load at 4 dpi (Fig. 5c) was observed in IL10−/−(DCB/Flu) mice compared to WT(DCB/Flu) mice.