Fig 1: Nascent KRT5+ Cell Appearance Occurs in a Proximal to Distal Pattern following PR8 Influenza Virus Infection in Mice and Results in Remodeling of the Distal LungPhotomicrographs of lung tissue sections from control mice (A–C) and mice recovered for 7 days (D–F), 10 days (G–I), or 14 days (J–L) following infection with PR8 influenza virus. For each time point the distal conducting airways and alveolar parenchyma panels are serial sections. Sections are immunostained for the basal cell marker KRT5 (green) and the pan-epithelial cell marker, E-cadherin (red), or the AT1 cell marker, PDPN (red), and the AT2 cell marker PROSP-C (green). For each panel the zoomed insert shows magnified boxed region without DAPI staining to highlight co-stained regions. At least three animals were analyzed per time point. Scale bar, 100 µm.