Control of adhesion and detachment of parenchymal liver cells using lactose-carrying polystyrene as substratum

Adhesion of hepatocytes on culture dishes whose surface was coated with a lactose-carrying styrene homopolymer (PVLA) was investigated. Hepatocytes maintained their round shape on PVLA substratum, which is in contrast to the usual spread shape characteristic of those cultured on collagen and fibronectin substrata. Calcium ion was indispensable for hepatocyte adhesion in PVLA substratum, and hence the hepatocytes on PVLA were easily detached when the culture was treated with ethylenediamine tetraacetic acid (EDTA). The recovered hepatocytes readheres to PVLA. The adhesion of hepatocytes to PVLA was not inhibited by cytochalasin B but by colchicine. Hepatocytes recognize the galactose moieties on the surface of asialoglycoproteins and removes these proteins from the blood stream by receptor mediated endocytosis. The mechanism of adhesion of hepatocytes on PVLA substratum which contains a high density of galactose residues was distinct from the attachment on collagen and fibronectin substrata, and showed great similarity to the receptor and ligand interactions which occurs in the clearance of asialoglycoproteins by hepatocytes.