HepG2细胞构成的生物人工肝脏体外氨与安定的代谢能力

Ammonia and diazepam metabolism capacities of a novel bioartificial liver with HepG2 cells

AIM: To establish a bioartificial liver (BAL) that can metabolize both ammonia and diazepam (DZP). METHODS: HepG2-GS-3A4 cell line was produced by transfecting cytochrome P450 3A4 (CYP3A4) gene into HepG2-GS, a cell line established by Enosawa et al by introducing glutamine sythetase (GS) gene into HepG2 cells. After the expression of CYP3A4 was verified by West-em blot and immunohistochemistry, HepG2-GS-3A4 cells were inoculated in a BAL circulatory reactor. When the cells grew to enough number, medium containing NH4Cl and DZP was infused. Samples were collected at fixed time. The concentrations of ammonia, DZP and its metabolites were analyzed by Berthelot reaction and HPLC. RESULTS: The expression of CYP3A4 in HepG2-GS-3A4 was much stronger than that in HepG2 (P= 0.02). The BAL with HepG2-GS-3A4 showed much higher capacities of ammonia and DZP metabolisms than those with HepG2 or no cells (P= 0.04 and 0.03). The concentra- tions of ammonia and DZP were decreased by 31.7% and 36.7%, respectively. CONCLUSION: BAL with HepG2-GS-3A4 processes strong activities of ammonia and DZP metabolism, with advantages of stability, easy subculture and storage, and abundance of cells.