title: Preparation of long-circulating immunoliposomes containing adriamycin by a novel method to coat immunoliposomes with poly(ethylene glycol).
abstract: Modifications of liposomes with poly (ethylene glycol) (PEG) have been reported to prolong blood circulation time of liposomes. In this report, an adriamycin-encapsulated immunoliposomes were modified with PEG by two different approaches: one is the pre-coating method using lipid derivative of PEG as described by Allen et al. The other is post-coating method which is presented here. The former pre-coating method did not allow coupling of antibody due to the steric hindrance of PEG which had been introduced on liposome surface. On the other hand, in the later post-coating method, PEG-succinylcysteine was synthesized and was successfully conjugated with immunoliposomes via maleimido linker. Resultant PEG-coated immunoliposomes containing adriamycin retained their binding activity and cytotoxicity to target cells, and also showed significantly prolonged blood circulating time as compared with conventional immunoliposomes. This is a novel method to coat immunoliposomes with PEG.
authors.affiliation: Department of Hygienic Chemistry, Faculty of pharmaceutical Sciences, Tohoku University, Sendai, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Masuko
authors.forename: Y
authors.initials: Y
authors.lastname: Hashimoto
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D002448:Cell Adhesion; D002455:Cell Division; D002460:Cell Line; D004317:Doxorubicin / Q000008:administration & dosage*; D006207:Half-Life; D006801:Humans; D008081:Liposomes / Q000138:chemical synthesis* / Q000276:immunology / Q000493:pharmacokinetics; D008297:Male; D051379:Mice; D011092:Polyethylene Glycols
chemical_list: D000906:Antibodies; D008081:Liposomes; D011092:Polyethylene Glycols; D004317:Doxorubicin