Three-dimensional primary hepatocyte culture in synthetic self-assembling peptide hydrogel

Drug metabolism studies and liver tissue engineering necessitate stable hepatocyte cultures that express liver functions for a minimum of 4 days to 3 weeks. Current techniques, using different biomaterials and geometries, that maintain hepatocellular function in vitro exhibit a low cell density and functional capacity per unit volume. Herein we investigated a well-defined synthetic peptide that can self-assemble into three-dimensional interweaving nanofiber scaffolds to form a hydrogel, PuraMatrix, as a substrate for hepatocyte culture. Freshly isolated primary rat hepatocytes attached, migrated, and formed spheroids within 3 days after seeding on PuraMatrix. Hepatocytes expressed the apical membrane marker dipeptidyl peptidase IV at cell-cell contacts. Compared to the collagen sandwich, albumin and urea secretion on PuraMatrix were higher for the first week, and cytochrome P450IA1 activity was higher throughout the culture period. Mitochondrial membrane potential 1 day after seeding was higher on PuraMatrix than in the collagen sandwich, suggesting better preservation of the metabolic machinery. PuraMatrix and Matrigel showed similar albumin and urea production. PuraMatrix is an attractive system for generating hepatocyte spheroids that quickly restore liver functions after seeding. This system is also amenable to scale-up, which makes it suitable for in vitro toxicity, hepatocyte transplantation, and bioartificial liver development studies.