Rapid Self‐Assembly Mini‐Livers Protect Mice Against Severe Hepatectomy‐Induced Liver Failure

Abstract The construction of bioartificial livers, such as liver organoids, offers significant promise for disease modeling, drug development, and regenerative medicine. However, existing methods for generating liver organoids have limitations, including lengthy and complex processes (taking 6–8 weeks or longer), safety concerns associated with pluripotency, limited functionality of pluripotent stem cell‐derived hepatocytes, and small, highly variable sizes (typically ≈50–500 µm in diameter). Prolonged culture also leads to the formation of necrotic cores, further restricting size and function. In this study, a straightforward and time‐efficient approach is developed for creating rapid self‐assembly mini‐livers (RSALs) within 12 h. Additionally, primary hepatocytes are significantly expanded in vitro for use as seeding cells. RSALs exhibit consistent larger sizes (5.5 mm in diameter), improved cell viability (99%), and enhanced liver functionality. Notably, RSALs are functionally vascularized within 2 weeks post‐transplantation into the mesentery of mice. These authentic hepatocyte‐based RSALs effectively protect mice from 90%‐hepatectomy‐induced liver failure, demonstrating the potential of bioartificial liver‐based therapy.