Figure 4. Influenza HA targeting mAb alters macrophage and neutrophil populations in the lung during influenza-associated bacterial pneumonia.

C57BL/6 mice infected with 100 PFUs of influenza A PR/8/34 and received a single dose of FY1 on days 1, 3, or 5 after influenza infection. Mice received secondary infection with 5 × 10⁷ CFUs of MRSA on day 6 after influenza and samples were harvested 24 hours following bacterial infection (n = 6). (A) CD11c⁺ cells in lung by flow cytometry. (B) CD11b⁺ cells in lung by flow cytometry. (C) CD11c⁺CD11b⁺ cells in lung by flow cytometry. (D) F480⁺ cells in lung by flow cytometry. (E) CD11c⁺F480⁺SiglecF⁺ cells in lung by flow cytometry. (F) CD11c^–F480⁺SiglecF^– cells in lung by flow cytometry. (G) CD11b⁺SiglecF⁺Ly6G^– cells in lung by flow cytometry. (H) CD11b⁺Ly6G⁺ cells in lung by flow cytometry. (I) Percentage of Ly6G^hiCD11b⁺ and Ly6G^loCD11b⁺ cells in the lung by flow cytometry. *P < 0.05. Significance was tested by 1-way ANOVA using Dunnett’s multiple comparison test. Data represent mean ± SEM.