Abstract Injection into rabbits of radioactive ceruloplasmin from which sialic acid had been removed enzymatically resulted in a rapid disappearance of the asialoceruloplasmin from the serum and its appearance in parenchymal cells, but not in Kupffer cells, of the liver. The rapidity of this transfer was dependent upon the presence of intact galactose residues as the terminal, nonreducing sugar of the carbohydrate moiety. Intact asialoceruloplasmin, doubly labeled with tritium and 64Cu, was isolated from the liver in good yield 24 min after intravenous injection.