The surface immobilization of galactose ligands on a PDMS substrate for use in primary rat hepatocyte culture

Abstract

After isolation from a living organism, primary hepatocytes markedly change their morphology and lose specific functions. This study aimed to utilize a simple solution-phase surface modification method to fabricate a galactosylated polydimethylsiloxane (GAL-PDMS) substratum. Using both Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) analysis, we demonstrated that the surface of PDMS was galactosylated. Furthermore, the density of the conjugated galactose ligands on the PDMS surface was 32.0±11.8μg/cm2. Galactose was chosen because it is a well-known ligand for the asialoglycoprotein receptor (ASGPR) in primary hepatocytes. We utilized primary rat hepatocytes to observe the cellular morphology and cellular function of hepatocytes on pristine PDMS, collagen-coated PDMS and GAL-PDMS. Based on cellular morphology, we found that cell spreading occurred on collagen-coated PDMS, whereas on the pristine PDMS or GAL-PDMS matrix, they retained their round morphology and gradually aggregated. On day 3, the cells showed a significantly higher level of viability on the GAL-PDMS than on the pristine and collagen-coated PDMS. Moreover, the hepatocytes cultured on GAL-PDMS could still express CYP450IA1 activity on day 8. These results suggested that the surface composition of PDMS influenced the adhesion, morphology and CYP450IA1 activity of hepatocyte. Hence, GAL-PDMS substrate is potentially applicable for drug-screening assays and tissue engineering.