Biodegradable and synthetic membranes for the expansion and functional differentiation of rat embryonic liver cells.

The insufficient availability of donor organs for orthotopic liver transplantation worldwide has urgently increased the requirement for new therapies for acute and chronic liver disease. The creation of an unlimited source of donor cells for hepatocyte transplantation therapy and pharmaceutical applications may be the isolation and expansion of liver progenitor cells or stem cells. Here we report the expansion and functional differentiation of rat embryonic liver cells on biodegradable and synthetic polymeric membranes in comparison with traditional substrates, such as collagen and polystyrene culture dishes. Membranes prepared from chitosan and modified polyetheretherketone were used for the culture of liver progenitor cells derived from rat embryonic liver. Cells proliferated, with a significant increase in their number within 8-11 days. The cells displayed functional differentiation showing urea synthesis, albumin production and diazepam biotransformation on all substrates investigated. In particular, on a chitosan membrane liver-specific functions were expressed at significantly higher levels for prolonged times compared with other synthetic membranes, utilizing traditional substrates (collagen and PSCD) as references. These results demonstrate that chitosan membranes offer cells favourable conditions to promote the expansion and functional differentiation of embryonic liver cells that could be effectively used in liver tissue engineering and in pharmaceutical applications.