IL-27 signaling influences bacterial clearance and cellular inflammation in influenza,
co-infection. C57BL/6, WT and IL-27Rα−/− mice, received 100 PFU of influenza A PR/8/34 or vehicle (PBS) for 6 days followed by 1x108 of S. aureus (ATTC 49775) or vehicle (PBS) for 24 hours. Bacterial colony counts in the lung were measured, n = 7 (A). Viral burden was determined by the measurement of influenza matrix protein mRNA gene expression in lung homogenate by RT-PCR, n = 7 (B). Cellular inflammation was examined by total cells per milliliter in the BAL (C), cell differentials (D) and hematoxylin and eosin-stained lung sections that were quantified for lung inflammation (KMR and JFA) blinded to the groups (E) with representative sections shown (F), n = 7. *p < 0.05 IL-27Rα−/− versus WT mice. All data are reported as means ± SEM for each group by unpaired t test (A-D) and two-way analysis of variance with the Bonferroni’s post-test (E). Data are the combined results of two replicate experiments.