Delayed oseltamivir plus sirolimus treatment relieved pH1N1-induced severe lung damage.

(A) Lung tissue injury was assessed by hematoxylin and eosin staining at 5 and 7 dpi. Scale bar = 100 μm, original magnification: ×200. (B) Semiquantitative histological scoring of lung injury. This experiment was done in a blinded manner. (C) Relative LDH activity in the bronchioalveolar lavage fluid of the infected mice following different treatments at the indicated dpi. (D) Viral titer in the lung homogenates of the infected mice following different treatments at the indicated dpi. Data are representative of two independent experiments and presented as mean ± SEM (n = 5 for each group). *, **, and *** represent p < 0.05, 0.01, and 0.001, respectively.