Synthesis and secretion of protein by hepatocytes entrapped within calcium alginate

The ability of entrapped hepatocytes to secrete plasma proteins was examined for the purpose of developing a biological artificial liver. Hepatocytes were isolated from adult rat liver by perfusion with collagenase. Isolated hepatocytes were entrapped within calcium alginate. The entrapped cells induced tyrosine aminotransferase (TAT) in the presence of dexamethasone and dibutyryl-cyclic AMP and retained the ability to induce TAT for 7 days. Moreover, entrapped cells could synthesize and secrete a biologically active form of coagulation Factor II, prothrombin. Two plasma proteins, lecithin: cholesterol acyltransferase and cholinesterase, were also secreted into the medium. Thus, hepatocytes within calcium alginate showed liver-specific characteristics, and these activities were almost comparable with those of monolayer-cultured cells.