(219f) Growing Tissue-like Constructs with Hep3b/Hepg2 Liver Cells on PHBV Microsphere Scaffold

Tissue engineering is a rapidly growing field where natural tissue substitutes are designed and generated in vitro for the replacement, repair and enhancement of defective tissue or organ failures. Our goal is to construct an engineered liver tissue using microspheres to reduce the cost of implantation and to solve the shortage of liver donors due to the high incidence of liver diseases and failure.

In this study, a water-in-oil-in-water emulsion solvent evaporation technique was used to fabricate poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV, 8% PHV) microspheres as scaffold to guide liver cell growth. Human hepatoma cell lines, HepG2 and Hep3B, were cultured in vitro on both the microspheres and polymer films. SEM and optical microscope images showed that multilayer cells were formed among the microspheres to bridge them together and developed into cell-construct aggregates after one week of culture, while only monolayer of cells formed on thin film. MTT results showed that the cell proliferation on the microspheres was more than 2 times higher than that on the films after 12 days of culture. The cells seeded on microspheres secreted albumin 2-4 times more than that on the positive control after one weeks of culture, which indicated that this hepatic function was greatly improved by the aggregation of cells on microspheres. Although HepG2 failed to express P-450 activity, this hepatic function was preserved when Hep3B cultured on microspheres. All the results indicated that PHBV microspheres are appropriate scaffolds for liver tissue engineering.