Simple mixing of IFN with a polysaccharide having high liver affinity enables IFN to target to the liver

Interferon (IFN) therapy is only one method that is clinically effective in controlling disease activity in patients with chronic hepatitis. A chelati ng residue (diethylenetriamine pentaacetic acid, DTPA) was introduced to pu llulan, which is a polysaccharide with high liver affinity. This DTPA-pullu lan could conjugate with IFN through Zn2+ coordination on mixing these thre e components. Intravenous injection of the IFN-DTPA-pullulan conjugate with Zn2+ coordination induced activity in the liver of an antiviral enzyme, 2' ,5'-oligoadenylate synthetase at IFN doses lower than those used for free I FN injection. In addition, synthetase induction by the conjugate continued for a longer time than did induction by free IFN, Liver targeting of IFN by this conjugation technique based on Zn2+ coordination opens a new method o f IFN therapy.