Fabrication and in vitro evaluation of a packed-bed bioreactor based on galactosylated poly(ethylene terephthalate) microfibrous scaffolds

Abstract

Bioartificial liver (BAL) comprising a functional bioreactor represents a promising treatment, bridging patients with acute liver failure (ALF) to liver transplantation. In this research, a packed-bed (PB) bioreactor by utilizing galactosylated poly(ethylene terephthalate) microfibrous carrier (PET-Gal) was fabricated and evaluated in vitro. Human induced hepatocytes (hiHeps) were dynamically seeded into a PET-Gal loaded bioreactor and cultured for 10 days. During perfusion culture, the effects of bioreactor scaffold on hepatocyte seeding, growth and functionality (albumin secretion and urea production) were determined, compared with that of control with non-modified PET carrier. Afterwards, drug metabolism and detoxification ability of hiHeps were measured. Results demonstrated that the seeding rate and proliferation fold within PET-Gal loaded bioreactor were significantly higher than that of control, resulting in a cell density of (8.17 ± 0.52)×107 cells/cm3. In contrast to flattened morphology observed in the control, hiHeps cultured in PET-Gal based bioreactor displayed as three-dimensional (3D) cell aggregates with close cell-matrix and cell-cell interactions and high cell viability, leading to higher albumin secretion and urea production. Besides, there were high levels of phase I drug metabolism and ammonia elimination for PET-Gal cultured cells. Therefore, the PET-Gal based PB bioreactor fabricated herein supports high-density hepatocyte growth and meanwhile preserves hepatic functionality, showing great potential in BAL systems application.