Fig. 6. Intestinal epithelial differentiation is not affected in Ad Dkk1-treated animals. Representative sections of the duodenum of Ad Fc- or Ad Dkk1-treated mice on day 2 after virus application were analyzed for the presence of differentiated intestinal epithelial cell types. (Top) FABP-L immunohistochemistry identifies absorptive enterocytes. (Middle) Alcian blue staining for secretory goblet cells is combined with anti-lysozyme immunohistochemistry (brown precipitate) marking Paneth cells.(Bottom) Gremelius staining for enteroendocrine cells. Rare positive cells are indicated by arrowheads.