Fig. 1

Proximal-to-distal distribution of KRT5⁺ and KRT14⁺ basal cells subpopulations in the healthy human lung. a, b Sections from healthy human lungs (6 donors) were co-stained for Keratin (KRT) 5 (green), KRT14 (red) and counterstained with DAPI (blue). Two representative pictures, with corresponding high magnification panels, are shown for the conducting airways (a left and right panels) and the distal airways (b left and right panels). Arrow: KRT5⁺ cell with characteristic luminal epithelial cell morphology. Full bars = 500 μm. Scattered bars = 100 μm. c Isolated primary human bronchial epithelial cells (hBEC) were co-stained for KRT 5 (green), KRT14 (red) and counterstained with DAPI (blue). The panels show: Keratin5-DAPI (left), Keratin14-DAPI (middle) and merged (right) images. Full bars = 500 μm. Scattered bars = 100 μm