E-cadherin is induced in lung alternatively activated macrophages elicited during allergic asthma, but not hypersensitivity pneumonitis. Allergic asthma and hypersensitivity pneumonitis were induced in C57BL/6 mice. (A) IL-4 and IFN-γ concentrations were measured in the BALF. (B) Alveolar and interstitial lung macrophages were purified and Cdh1 expression in freshly isolated cells was determined. The fold induction of gene expression relative to the expression in naive alveolar macrophages (= 1) is shown. Naive alveolar macrophages were also cultured for 24 hours with or without IL-4 (in vitro + IL-4). The fold induction of Cdh1 gene expression in IL-4–treated relative to untreated alveolar macrophages (= 1) is shown. (C) BALs were stained with anti-CD11c and anti–E-cadherin or isotype control and analyzed via FACS. Within gated CD11c^high BAL, a distinction was made between AF^low DC and AF^high alveolar macrophages and histogram overlays of isotype staining (dotted) and anti-E-cadherin staining (bold) are shown.