Figure 1

Immunofluorescence microscopy analysis and TEER measurement of well-differentiated porcine tracheal and bronchial epithelial cells (PTEC and PBEC) grown under air–liquid interface (ALI) conditions.
Porcine epithelial cells from PTEC or PBEC, were grown to confluence on filter supports and maintained under ALI conditions for five (A–D, F) or seven weeks. The extent of differentiation was analyzed by visualizing cilia (A,B,E) and mucus (A,B), tight junctions (C,D) and by measuring the transepithelial resistance (F). For analysis by immunofluorescence microscopy, PTEC (A,C) and PBEC (B,D) were stained for cilia by anti-β-tubulin antibodies (A,B, red) and for mucus (A,B, green), respectively. Tight junctions were visualized by staining for occludin (C,D, green). (E) Analysis of PBEC by FESEM differentiated for 7 weeks. (F) TEER values of PTEC and PBEC during differentiation. The day of cell seeding is indicated by arrowhead (day 1). Bars represent 50 μm (A,B) and 10 μm (C–E).