Representative immunofluorescence staining for complement component deposition in the middle ear mucosa.

<p>(A) C3 (green) and C5aR (red) deposition in the middle ear mucosa at 24 h post Spn infection. Nucleic acids were stained with DAPI (blue). Faint staining was observed in sham control mice. Increased C3 and C5aR immunofluorescence staining in the middle ear epithelium of mice infected with IAV and Spn was evident. (B). Increased C5b-9 immunofluorescence staining (green) in the middle ear epithelium in mice at 24 after transtympanical inoculation with Spn with a prior IAV infection compared with the sham control and single pathogen infected cohorts. Arrows indicate the middle ear mucosa. Representative imagines from three mice are shown.