Indium-111-labeled liposomes: quality and biodistribution in mice bearing human tumor xenografts

Abstract

AbstractPhospholipid vesicles containing the ionophore A23187 in the bilayer (VesCan) are the only liposomes produced for clinical imaging purposes. We undertook preliminary experiments with In-loaded VesCan (indium-111-V-liposome) using normal rabbits and nude mice bearing human gastric (MKN45) and colon (COL0205) tumor xenografts before clinical application of the product. Two V-liposome vials with different expiration dates were labeled with 111In and then injected into rabbits immediately or 24 h after loading. The blood clearances of 111In were not significantly different from rabbit to rabbit, indicating that 111In-V-liposomes did not vary among vial lots. Both MKN45 and COL0205 tumor xenografts in nude mice were successfully imaged with 111In-V-liposome; V-liposome delivered sufficient radioactivity to allow tumor visualization as early as 8 h after iv injection. It was also found that MKN45 tumors exhibited uptake of 6.5% ID/g. The present results indicated that the quality and shelf life of 111In-V-liposomes are good and that scintigraphy of 111In-V-liposomes is a feasible technique for detecting tumor lesion in patients with cancer.