Figure 4
Immunofluorescent analysis of in vitro cultured airway epithelial cells. Human and porcine tracheal and bronchial epithelial cells at the starting (pIII), middle (pVI), and late (pIX) cell culture passages were stained for different markers. (a) CK7 (red) was detected in almost all human cultured cells, whereas only some sopra-basal differentiated porcine cells highly expressed this columnar epithelial cell marker. (b) ZO-1 protein (green) was barely detectable in human tracheal and bronchial cells, whereas it was expressed by sopra-basal porcine epithelial cells (white arrows). (c) Goblet cells identified by MUC5AC glycoprotein (red) were similarly detected in human and porcine airway epithelial cell cultures. (d) Within the standard submerged culture conditions, acetylated α-tubulin (red) was expressed at basal levels by almost all cultured human epithelial cells, while it increased especially in middle (pVI) and late (pIX) passages of porcine epithelial cells. Nuclei were counterstained with DAPI, scale bar = 50 µm. p = passage.
