Figure 3

Sections of UIP/IPF lung treated for the immunohistochemical localization of Wnt7B. Figure3a demonstrates staining of hypertrophic/metaplastic alveolar epithelial cells. Figure3b demonstrates extensive subepithelial (SE, not an FF) site reactivity (arrows) around one side of a small airway. Figure3c demonstrates reactivity within a fibroblastic focus (FF) and adjacent SE sites (arrows). The inset at higher magnification of the fibroblastic foci demonstrates the extracellular matrix and cellular (arrow) nature of the reactivity. Figure3d demonstrates extensive subepithelial (SE) site reactivity (arrows) around two small airways, the apparent reactivity of presumptive basal cells (arrows) within the respective airways. The inset at higher magnification shows presumptive, reactive fibroblasts embedded within reactive matrix (arrowheads). Methylene blue counterstain. Bars = 50 μm; inset bars = 30 μm.