Fig. 3

Immunohistochemistry for markers of alveolar type II cells and AAV entry receptors. Representative images are shown of fixed-frozen sections of LBOs (n = 2–3), with nuclei stained with DAPI (blue) and various markers (red), including ATII cell marker SP-C (a), ATII cell marker SP-B (b, c), universal AAV co-receptor AAVR (d), glycan receptor α-2,3-linked sialic acid (e, f) and glycan receptor heparan sulphate (g, h). Native fluorescence is observed following microinjection of AAV6.2-CMV-eGFP (c) compared with negative control LBOs (b). Sections digested with sialidase A (e) and heparinase III (g) to remove glycans are included as negative staining controls. Staining controls for images a–d are shown in suppl. Fig. 2. Scale bar 50 μm