Enhancement and Maintenance of Hepatic Metabolic Functions by Controlling Three-Dimensional Aggregation of Cryo-Preserved Human iPS Cells Derived Hepatocyte-Like Cells

Hepatocyte-like cells (HLCs) generated from human induced pluripotent stem cells are potent cells to study individual-specific hepatotoxicity for drug screening test. However, the functions of metabolic enzymes are practically low. 3D spheroid is a potent strategy to enhance the differentiation efficacy from undifferentiated cells, but 3D formation of “differentiated” HLCs is not fully examined. Here, we successfully reconstituted stable and compact 3D spheroids of commercially available cryo-preserved HLCs by our original spheroid formation method with high viscous methylcellulose medium, while conventional formation methods never formed the spheroid. 3D formation enhanced the hepatic functions and maintained the functions for 14 days. Especially, drug-metabolizing enzymes, cytochrome P450, were 10- to 100-fold enhanced compared to conventional 2D culture, which is applicable to a typical drug-metabolizing test using LC-MS/MS. Our formation method has an impact on functional spheroid formation.