The Effect of Culture Conditions on Liver Function and Proliferation of Hepatic Cells for Bio-Artificial Liver

Abstract Bio-artificial liver (BAL) is an effective treatment for serious liver disease. It is thought that a mass of hepatic cells corresponding to 30% of the liver are needed for BALs, and a small size of reactor, at most a few liters in volume, is desired for use at the hospital bedside. Therefore, high-density culture, ≥1 × 10⁷ cells/cm³, should be employed. However, sufficient oxygen and nutrients are not supplied to all cells in the reactor, resulting in apoptosis and serious impairment to BAL performance. In order to solve these problems, we have previously introduced anti-apoptosis gene bcl-2 into HepG2 cells, establishing an anti-apoptosis cell line, Hep-Bcl2. The Hep-Bcl2 cell line survived under low oxygen conditions, and had twice the level of albumin productivity than do HepG2 cells. In this study, the Hep-Bcl2 cell line was cultured under high-density conditions, with a change of culture medium twice daily to mimic the circulation. In this way, Hep-Bcl2 successfully maintained a high population for at least 14 days, and the albumin productivity of Hep-Bcl2 was significantly higher than that of HepG2 cells.