Figure 1.

CD47^−/− mice have an enhanced clearance of influenza virus

Wildtype (WT) and CD47^−/− mice were i.n. infected with a single dose of 75 PFU of influenza virus A/PR8/34.

(A–C) (A) F4/80⁺ macrophages (MΦ) in the lung were analyzed 3 days post infection (dpi) via flow cytometry regarding the mean fluorescence intensity (MFI) of CD47. Viral loads in the lung of mice infected with 75 PFU IAV was determined at day 3 (B) and 7 (C) after infection via plaque assay.

(D) Immune induced histopathology in the lung was determined at 7 dpi.

(E) Body weight change after infection.

(F) Pro-inflammatory cytokines including TNF-α, IL-1β and IFN-α were determined in the BALF at indicated timepoints via Luminex and ELISA.

(G) Alveolar type II epithelial cells were isolated from the lung and ex vivo infected with indicated doses. Virus titers were assessed by qRT-PCR 2 dpi (n = 4). Results are pooled from two or more independent experiments.

Data shown are mean ± SEM. Statistics were done by Student’s t test in (A). Two-way ANOVA with Sidak’s multiple-comparisons post-test was used in all other figures. one-way ANOVA with Tukey’s multiple-comparisons post-test was performed in (F). ∗ = p < 0.05, ∗∗ = p < 0.01.