Design of hepatocyte-specific extracellular matrices for hybrid artificial liver

For the development of an artificial liver which can assist multiple metabolic functions of liver, the effective cultivation of hepatocytes on substrate as etracellular matrix analogs was examined. Adult rat hepatocytes attached on an asialoglycoprotein model polymer, poly-N-p-vinylbenzyl-Dlactonamide (PVLA), formed anchored multilayer aggregates which had a stable three-dimensional structure when epidermal growth factor (EGF) and insulin were added to the culture medium. The formation of multilayer aggregates was also dependent on the specific cellular attachment mediated by asialoglycoprotein receptor of hepatocyte surface. Cells in the aggregates expressed higher level of albumin secretion and lower proliferative ability than those in monolayer cultures on collagen. It seemed likely that the cells in multilayer aggregates experienced stable differentiated states resembling in vivo status through the forming multilayer aggregates. The culture system described here has useful potentiality for the development of hepatic module systems for a hybrid artificial liver.