Figure 2.

Endothelial cell (EC) co-culture increases differentiation of basal cells (BC) into ciliated cells. Basal cells were cultured alone or co-cultured with EC at a 10:1 and 2:1 (BC:EC) ratio on air-liquid interface (ALI) culture for 28 days to assess the impact of EC on BC differentiation into a mucociliated epithelium at the histological level via immunofluorescence staining with cell type specific markers. A. KRT5⁺ BC. Sections of cells were stained for KRT5 (red) and DAPI (nuclei, blue). B. KRT8⁺ intermediate cells. Sections of cells were stained for KRT8 (red) and DAPI (nuclei, blue). C. SCGB1A1⁺ secretory cells. Sections of cells were stained for SCGB1A1 (red) and DAPI (nuclei, blue). D. MUC5B⁺ secretory cells. Sections of cells were stained for MUC5B (red) and DAPI (nuclei, blue). E β-tubulin IV⁺ cells. Sections of cells were stained for β-tubulin IV (ciliated, green) and DAPI (nuclei, blue). A–E. Scale bar 20 μm. H. Quantification of KRT5⁺, KRT8⁺, SCGB1A1⁺, MUC5B⁺ and β-tubulin IV⁺ cells. The bars indicate the mean for n=4 independent experiments and error bars indicate standard error of the mean. Asterisks (*) indicate p<0.05 compared to BC cultured alone. The experiments for A–H were performed with n=4 independent donors of BC and EC.