Fig. 8. Phospho-SMAD1 and ß-catenin expression is increased in human dysplastic fetal kidney. (A-C) Phospho-SMAD1 expression detected by immunohistochemistry using anti-phospho-SMAD1 and HRP-conjugated secondary antibodies. (A) Phospho-SMAD1 is undectable in normal Hematoxylin-stained tissue. (B) Phospho-SMAD1 is markedly unregulated in Hematoxylin-stained dysplastic tissue (red cells), including a branched ureteric bud (arrowhead) and in cysts (C). (D-I) ß-catenin expression detected by immunohistochemistry using anti-ß-catenin and HRP-conjugated secondary antibodies. (D,G) ß-catenin is weakly expressed in epithelial tubules (arrows) of Hematoxylin-stained normal kidney tissue. (E,F) ß-catenin is highly expressed in epithelial tubules (arrows) of Hematoxylin-stained dysplastic kidney tissue. (H,I) ß-catenin is highly expressed in the epithelium of ureteric bud-derived cysts. (H) ß-catenin is highly expressed in cyst epithelium (arrow). (I) Fluoresence image of cyst in H stained with fluorescence-conjugated DBA. Positive staining demonstrates that the cyst is derived from the ureteric bud.