3D‐Printed Mesh‐Walled Microtube System Enables a Vascular‐Biliary‐Incorporated Liver‐on‐a‐Chip

ABSTRACT Biomimetic liver models that faithfully recapitulate physiological structure and function are vital for assessing drug‐induced hepatotoxicity. Existing liver models usually lack vascular and biliary dual systems, the challenge of which lies in achieving precise multicellular spatial organization, stable lumens, and functionally coupled interactions among hepatic parenchyma, vasculature, and bile ducts. Here, we developed a 3D‐printed vascular‐biliary‐incorporated liver‐on‐a‐chip (VBL) by projection micro‐stereolithography (PµSL) printing strategy to construct a heterogeneous liver model. The vascular‐biliary‐incorporated liver‐on‐a‐chip features mesh‐walled microtubes with high permeability and vessel‐like elasticity. The mesh‐like structure enhances surface wettability and enables endothelial cells and biliary epithelial cells to infiltrate the microtubes under capillary‐driven flow to form functional microvasculature and microbile ducts. By further incorporating hepatic parenchyma, the liver model establishes direct heterotypic cell–cell contact among hepatocytes, endothelial cells, and biliary epithelial cells, generating well‐defined and interconnected hepato‐vascular‐biliary compartments under perfused culture conditions. Additionally, the vascular‐biliary‐incorporated liver‐on‐a‐chip exhibits enhanced hepatic functions, multicellular crosstalk, and the formation of bile canaliculi‐like structures, conferring increased sensitivity to drug‐induced hepatotoxicity. Collectively, the vascular‐biliary‐incorporated liver‐on‐a‐chip enables the stepwise construction of a biomimetic liver model, providing a new platform for drug‐induced hepatotoxicity assessment.