947072.fig.002
Figure 2: SEM image (a), immunostaining (b) for occludin, claudin-1 and tricellulin, and freeze-fracture image (c) in human nasal mucosa in vivo. Scanning electron microscopy (SEM) image (d), phase contrast (e), immunostaining (f) for occludin, claudin-1 and tricellulin, and freeze-fracture image (g) in human nasal epithelial cells in vitro (hTERT-HNECs). Scale bars: (a) and  nm, (b) and μm, and  nm, and μm.