To further confirm the severe inflammatory response in the MBL WT mice compared with MBL KO mice, lung sections were stained with H&E for histological analysis to evaluate inflammation-associated lung damage caused by pdmH1N1 and H9N2/G1 influenza virus infection. In the histological sections of MBL WT mice, more severe lung inflammation and more cell infiltration were observed when compared to that of MBL KO mice on day 7 ( Figure 6 ). Consistent with our cytokine and chemokine data, the pulmonary histological analysis suggested that the MBL WT mice had a more severe inflammatory response upon pdmH1N1 and H9N2/G1 virus infection.