Figure 1.

Histological assessment of the effect of EGF on epithelial morphology of BBEC cultures. BBEC cultures were grown for 21 days at an ALI with varying concentrations of EGF before being fixed and paraffin-embedded using standard histological techniques; samples of ex vivo tissue were also taken from the donor animal. Sections were cut, deparaffinised and stained using (A) H&E, (B) immunohistochemical-labelling of basal cells (p63-labelled cells display brown nuclei) and (C) PAS (black arrowheads indicate goblet cells). Representative images are shown of (i) ex vivo bovine bronchial epithelium, and BBECs grown in the presence of (ii) 0 and (iii) 10 ng/ml EGF (see Fig. S1). Quantitative analysis (using ImageJ) of histological sections of BBEC layers grown in the presence of 0, 1.0, 2.5, 5.0, 10.0, 25.0 and 50.0 ng/ml EGF (see Fig. S1A), and ex vivo tissue, showing (D) epithelial thickness and (E) the number of cell layers comprising the epithelium was performed. For each insert, three measurements were taken (left, centre and right) in each of five 400x fields of view evenly distributed across the sample; three inserts were analysed per growth condition and the data represents the mean +/− standard deviation from tissue derived from three different animals. Statistical significance was tested using an Ordinary one-way ANOVA: **** = P < 0.0001.