Figure 3: Immunohistochemical features of cryosectioned tubules generated for 13 days at the interface of an artificial interstitium. (a) Positive label for cingulin exhibited polarization of epithelial cells. (b) Strong label for cytokeratin 19 and (c) TROMA-I (cytokeratin endoA) depicted typical occurrence of intermediate sized filaments. (d) Intense reaction for Na/K-ATPase α5 was found at the basolateral aspect of epithelial cells. (e) Laminin γ1 was detected within the basal lamina of tubules. (f) Label for collagen III was present in the interstitial space between generated tubules. Tubule (T), lumen (arrow) and basal lamina (asterisk).