Abstract
In order to develop a hybrid artificial liver and a hepatic biosimulator for the analysis of drug metabolism, it is important to design some attachment substratum to maintain its differentiated function and longevity. It is considered that the peptide bond, conformation, balance of electric charge play important roles in the specific interactions for the stability of bonding and the selectivity. So we imitated them, and synthesized polypeptides containing different compositions of lysine, glutamic acid, leucine. Then we studied the attachment of hepatocytes to these polypeptides to make clear the interactions between hepatocytes and these polypeptides. Hepatocytes showed high adhesion to the polypeptides containing much lysine residue (Cation rich polypeptides). Hepatocytes on cation rich polypeptides exhibit better maintenance of liver specific functions as well as on collagen. Furthermore, hepatocytes cultured under the hormone supplemented medium formed remarkably multicellular spheroid within 3 days, then multicellular spheroid floated gradually from the surface of the dishes. It was interesting phenomenon that hepatocytes cultured on synthetic polypeptide formed floating multicellular spheroid by the stimulation of suppremented hormones. Polypeptides which have the activity of the forming spheroid in culture are very useful materials for the reconstruction of the liver tissue. Further studies using cultured system described here may be carried out to clarify the mechanism of spheroid formation in hepatocytes culture.
