Development of a 3D Cell Culture System Using Amphiphilic Polydepsipeptides and Its Application to Hepatic Differentiation.

Various three-dimensional (3D) culture systems are available to provide more accurate in vivo mimicry than two-dimensional (2D) cultures. Synthetic and/or xeno-free biomaterials are desired, as they would provide lower batch-to-batch variability and high repeatability. Here, we introduce a 3D culture system using nanofibers composed of an amphiphilic polydepsipeptide-based polymer named HYDROX, which turns into 3D nanofibers after hydration.

Comparison of commercially available media for hepatic differentiation and hepatocyte maintenance.

Human hepatocytes are essential materials in pharmaceutical researches. Not only primary human hepatocytes (PHH) but also human iPS cell-derived hepatocyte-like cells (human iPS-HLCs) are expected to be applied as materials for pharmaceutical researches. To date, several culture media have been developed for culturing human hepatocytes.

Tolloid-Like 1 Negatively Regulates Hepatic Differentiation of Human Induced Pluripotent Stem Cells Through Transforming Growth Factor Beta Signaling.

Single nucleotide polymorphisms in Tolloid-like 1 (TLL1) and the expression of are known to be closely related to hepatocarcinogenesis after hepatitis C virus elimination or liver fibrosis in patients with nonalcoholic fatty liver disease. TLL1 is a type of matrix metalloprotease and has two isoforms in humans, with the short isoform showing higher activity. However, the functional role of TLL1 in human liver development is unknown.

Modeling of Hepatic Drug Metabolism and Responses in CYP2C19 Poor Metabolizer Using Genetically Manipulated Human iPS cells.

Cytochrome P450 family 2 subfamily C member 19 (CYP2C19), in liver, plays important roles in terms of drug metabolism. It is known that CYP2C19 poor metabolizers (PMs) lack CYP2C19 metabolic capacity. Thus, unexpected drug-induced liver injury or decrease of drug efficacy would be caused in CYP2C19 substrate-treated CYP2C19 PMs.

FGF signal is not required for hepatoblast differentiation of human iPS cells.

Human induced pluripotent stem cell-derived hepatocyte-like cells are expected to be utilized in pharmaceutical research and regenerative medicine. In general, human induced pluripotent stem (iPS) cells are differentiated into hepatocyte-like cells through definitive endoderm cells and hepatoblast-like cells using various growth factors that are essential for liver development. Although recombinant bone morphogenetic proteins (BMPs) and fibroblast growth factors (FGFs) are widely used in the hepatoblast differentiation, hepatoblast differentiation process has not been fully modified.

Enrichment of high-functioning human iPS cell-derived hepatocyte-like cells for pharmaceutical research.

Human iPS cell-derived hepatocyte-like cells are expected to be utilized in pharmaceutical research. However, the purity of high-functioning hepatocyte-like cells is not high enough. In particular, the purity of cytochrome P450 3A4 (CYP3A4), which is a representative hepatic drug-metabolizing enzyme, positive cells is still quite low (approximately 20%).

Nanaomycin A Treatment Promotes Hepatoblast Differentiation from Human iPS Cells.

Human induced pluripotent stem cell-derived hepatocyte-like cells (HLCs) are expected to be utilized in pharmaceutical research, including drug screening. However, the hepatocyte functions of the HLCs are still lower than those of human hepatocytes. Therefore, we attempted to improve the hepatocyte differentiation method by modulating the DNA epigenetic status.