Immobilization of ligand-modified polyamidoamine dendrimer for cultivation of hepatoma cells

Cationic polyamidoamine dendrimers are known to be highly branched cascade polymers. The core part of these polymers, tris(2-aminoethyl)amine, was immobilized onto polystyrene plates to which animal cells do not adhere. using photoreactive 4-(3-trifluoromethylazirino) benzoyl-N-succinimide (TDBA-OSu). Cells of a rat hepatoma cell line, H4-II-E-C3, adhered to a surface immobilized with a first-generation dendrimer probably through interactions between the terminal amino groups of the dendrimer and the cell membranes. The adhered cells were viable, could proliferate, and exhibited urea synthetic activity. The modification of the terminal amino groups with fructose increased the final number of cells obtained after 5 days of cultivation. Multigeneration dendrimers were prepared by repeated linkage of tris(2-aminoethyl)amine with the amino groups. Theoretically, the number of terminal amino groups available for ligand modification is twice as much for each generation of dendrimer growth. Cells cultivated on multigeneration fructose-modified dendrimers exhibited enhanced urea synthetic activity. The use of ligand-modified dendrimers is, therefore, considered to be very promising for the construction of bioartificial organs based on cultivation of the animal cells.