Generation of 3D tubular bile duct within human iPSC-derived liver organoid by incorporating human iPSC-derived blood vessel [scRNA-seq]

The tubular structure of the intrahepatic bile duct (BD) is crucial for its physiological functions including bile excretion. Although several human induced pluripotent stem cell (hiPSC)-derived liver organoids were generated, no prior study could emulate the development of BD tubules. Here we focus on the environmental cue to initiate BD development, specifically the interaction between liver progenitors and the portal vein (PV). We co-cultured hiPSC-liver progenitors with hiPSC-blood vessels (hiPSC-BV) consisting of immature hiPSC-smooth muscle cells (SMC) expressing JAG1, a key factor for cholangiocyte induction. After three weeks, liver progenitors within hiPSC-BV-integrated liver organoids (BVLO) differentiate into cholangiocyte lineage and establish tubular structures with epithelial characteristics, including intercellular junctions, microvilli on the apical membrane, and secretory functions. Furthermore, liver surface transplanted-BVLO demonstrated BD graft-host connection and suggested therapeutical potential. Overall, we developed a novel 3D co-culture method to establish functional human tubular BDs by emulating PV-BD interaction. scRNA expression profiles of iPSC-derived organoid