Fig. 4

Morphogenesis of tubular bile duct structure established within the 17 day triple co-culture period. a Three-sided imagery of phalloidin and Hoechst staining resembling the tubular structure of an in vitro bile duct (white arrow), displaying continuous lumen structure within the tubular structure. b Tubular structure showed significant upregulation of Jagged1, Notch2, and Cldn15 within 17 days of culture (β-actin was used as the housekeeping gene, n = 5; three independent experiments; values are means ± SD; *P < 0.05)