Peptide nanofiber hydrogel induces formation of bile canaliculi structures in three-dimensional hepatic cell culture.

Current hepatocyte models do not mimic the human liver morphology and functions properly and, therefore, drug metabolism, excretion, and toxicity in the liver are inadequately predicted. In this study, we established three-dimensional (3D) hepatic cell cultures in hydrogels of peptide nanofibers. The aim was to establish an improved 3D phenotype of HepG2 cells. In 3D hydrogel cultures, HepG2 cells formed multicellular spheroids that displayed filamentous actin accumulation and large tubular bile canalicular structures indicative of apicobasal cell polarity. Confocal imaging revealed the multidrug resistance-associated protein 2 (MRP2) and the multidrug resistance protein 1 (MDR1) localization on the bile canalicular membrane, and vectorial transport of fluorescent probes into bile canalicular structures. We conclude that 3D HepG2 cultures exhibited structural and functional polarity, suggesting that this model may be useful in drug research. This study shows the potential of 3D peptide nanofiber biomaterials in optimizing the cellular phenotype in organotypic cultures.