The newly established human liver cell line: a potential cell source for the bioartificial liver in the future

Abstract

The clinical use of a bioartificial liver (BAL) device strongly depends on the development of human liver cell lines. The aim of this study was to establish and assess the potential use of the stable HepG2 cell line expressing human augmenter of liver regeneration (hALR). The cDNA encoding hALR protein was inserted into pcDNA3.1 to generate pcDNA3.1/hALR, following which pcDNA3.1/hALR was transfected to HepG2 to establish a cell line that stably expressed hALR (HepG2 hALR). A total of 800 million HepG2 hALR cells were loaded into laboratory-scale BAL bioreactors and cultured for 4 days, during which time the parameters of hepatocyte-specific function and general metabolism were determined. The cell line that stably expressed human ALR was successfully established. The expression of recombinant hALR was higher in the HepG2 hALR cell line than in the HepG2 cell line based on immunofluorescence and immunoblot assays. In samples removed from the BAL bioreactor on day 4, compared to HepG2 cells, HepG2 hALR cells produced significantly more alpha-fetoprotein (127.3 %; P < 0.05) and urea (128.8 %; P < 0.05) and eliminated more glucose (135.7 %; P < 0.05); the level of human albumin was also higher (117 %) in HepG2 hALR cells, but the difference was not significant (P > 0.05). After 24 h of culture, the mean lidocaine removal rate was 65.1 and 57.3 % in culture supernatants of HepG2 hALR and HepG2 cell lines, respectively (P < 0.01). Based on these results, we conclude that HepG2 hALR cells showed liver-specific functionality when cultured inside the bioreactor and would therefore be a potential cell source for BAL.

Cell sources forin vitrohuman liver cell culture models

“…For example, transfection of HepG2 cells with human augmenter of liver regeneration resulted in increased synthesis of alpha-fetoprotein, urea, and albumin in comparison to non-transfected control cells. 76 An improvement in liver-specific functions, including expression of drug-metabolizing enzymes, was also observed after transient transfection of human hepatic cells with hepatocyte nuclear factor 4 alpha (HNF4a). 77 Using a lentiviral expression system, a range of cell lines were generated that express specific CYP enzymes individually and thus can be used to assess metabolism-associated toxicity of drugs.…”

Reversibly immortalized hepatic progenitor cell line containing double suicide genes

“…At present, identifying a reliable cell source is the most important issue to be addressed in BAL technology ( 16 ). To date, cell sources for liver cell-based therapies have included autologous, allogeneic or xenogeneic mature hepatic cells, differentiated hepatic cells from bone marrow hematopoietic stem cells, embryonic liver cells and hepatic oval cells ( 4 , 17 , 18 ). For BAL application, primary hepatic cells must be amplified to several orders of magnitude in vitro , and must also be capable of protein synthesis and metabolic detoxification functioning.…”

Establishment and characterization of an immortalized human hepatocyte line for the development of bioartificial liver system

“…Cryopreserved porcine cells and human primary hepatocytes have been the most frequently used as the biocomponent in BAL system (Demetriou et al 2004;Lee et al 2017). However, the risk of zoonoses of porcine cell (Sakiyama et al 2017) and the shortage as well as the poor proliferation capacity of human primary hepatocytes (Liu et al 2013) rendered it necessary to explore other sources of biomaterials. For these reasons, liver-tumor-derived cell lines have been extensively studied for development of the BAL.…”