title: Intravenous avidin chase improved localization of radiolabeled streptavidin in intraperitoneal xenograft pretargeted with biotinylated antibody.
abstract: In the present study, we examined the effect of avidin administered intravenously (i.v.) on the biodistribution of radiolabeled streptavidin in mice bearing intraperitoneal (IP) xenografts pretargeted with biotinylated antibody. Tumors were established in nude mice by IP inoculation of LS180 human colon cancer cells. Monoclonal antibody MLS128, which recognizes Tn antigen on mucin, was biotinylated and injected IP into the IP tumor-bearing mice. Radioiodinated streptavidin was administered IP or i.v. 48 h after pretargeting of biotinylated antibody. Avidin was administered i.v. 30 min prior to streptavidin injection. The localization of radioiodinated streptavidin in the tumor pretargeted with biotinylated antibody was significantly higher than that without pretargeting and that of radioiodinated MLS128 by the one-step method. Avidin administration significantly accelerated the clearance of radioiodinated streptavidin in blood and other normal tissues and increased the tumor-to-blood radioactivity ratio regardless of administration route of streptavidin. The i.v. avidin chase improved tumor localization of radiolabeled streptavidin in the IP xenografts pretargeted with biotinylated antibody.
authors.affiliation: Department of Nuclear Medicine, Faculty of Medicine, Kyoto University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Sakahara
authors.forename: Z
authors.initials: Z
authors.lastname: Yao
authors.forename: T
authors.initials: T
authors.lastname: Saga
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamoto
authors.forename: N
authors.initials: N
authors.lastname: Sato
authors.forename: H
authors.initials: H
authors.lastname: Nakada
authors.forename: I
authors.initials: I
authors.lastname: Yamashina
authors.forename: J
authors.initials: J
authors.lastname: Konishi
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism / Q000493:pharmacokinetics; D001360:Avidin / Q000008:administration & dosage / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000493:pharmacokinetics*; D001710:Biotin / Q000276:immunology / Q000378:metabolism; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007457:Iodine Radioisotopes; D051379:Mice; D008819:Mice, Nude; D009374:Neoplasms, Experimental / Q000378:metabolism; D019809:Streptavidin; D014018:Tissue Distribution / Q000187:drug effects; D014183:Transplantation, Heterologous
chemical_list: D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; D007457:Iodine Radioisotopes; D001360:Avidin; D001710:Biotin; D019809:Streptavidin