Figure 7.

Identification of IL-13–dependent ciliated-to-goblet cell transdifferentiation in vitro. Representative transmission electron micrographs are shown for cultured mTECs before treatment (upper left panel) and then after treatment with IL-13 (100 ng/ml for 2 days at 37°C; all other panels). Early cilia-goblet cells are identified with cilia that are visible on the surface of cells that also contain a few mucous granules, late cilia-goblet cells exhibit greater numbers of mucous granules in the cytoplasm, and mature goblet cells contain characteristic mucous granules with no cilia.