Fig. 6

CS restrains overall inflammation in the lung at day 7 but increases inflammation at day 10 post IAV infection. For CS groups, the mice were exposed to CS for 6 weeks in a smoke exposure chamber. Then the mice were intranasally infected with a non-lethal dose of IAV PR8 (300 pfu/mouse) or mock infected with PBS. a Total protein concentration in BALF. BALF was harvested at the indicated time points after infection. Total protein levels in BALF were determined. Data are expressed as means ± SEM (n = 4). b Total CD45 + leukocytes in the lung. Lung cells were isolated and stained for flow cytometry to determine the total numbers of CD45 + cells (n = 5). c Granzyme B protein levels in BALF were determined by ELISA. d Granzyme B and e IAV M1 Protein mRNA levels in the lung were assessed by qRT-PCR and normalized to β-actin. Data are expressed as means ± SEM. * denotes a significant difference compared to the PR8 infected NS group at the same time point (P < 0.05)