Abstract
In vitro drug screening using reliable and predictable liver models remains a challenge. The identification of an ideal biological substrate is essential to maintain hepatocyte functions during in vitro culture. Here, we developed a fiber-embedded polydimethylsiloxane (PDMS) chip to culture hepatocytes. Hepatocyte spheroids formed in this device were subjected to different flow rates, of which a flow rate of 50 μL/min provided the optimal microenvironment for spheroid formation, maintained significantly higher rates of albumin and urea synthesis, yielded higher CYP3A1 (cytochrome P450 3A1) and CYP2C11 (cytochrome P450 2C11) enzyme activities for metabolism, and demonstrated higher expression levels of liver-specific genes. In vitro metabolism tests on tolbutamide and testosterone by hepatocytes indicated predicted clearance rates of 1.98 ± 0.43 and 40.80 ± 10.13 mL/min/kg, respectively, which showed a good in vitro⁻in vivo correspondence. These results indicate that this system provides a strategy for the construction of functional engineered liver tissue that can be used to study drug metabolism.