Polymeric Micelle of A3B-Type Lactosome as a Vehicle for Targeting Meningeal Dissemination

Polymeric micelle of the A(3)B-type lactosome comprising (poly(sarcosine))(3)-b-poly(L-lactic acid) was labeled with In-111. The In-111-labeled A(3)B-type lactosome was administered to the model mice bearing meningeal dissemination and bone metastasis at mandible. With single-photon emission computed tomography (SPECT) imaging, the meningeal dissemination was identified successfully by In-111-labeled A(3)B-type lactosome, which was superior to (TlCl)-Tl-201 in regard of the imaging contrast. The In-111-labeled A(3)B-type lactosome was also potential in imaging selectively of bone metastasis at mandible, whilst a nonspecific imaging of the whole bone was obtained by the SPECT imaging using Tc-99m-HMDP. The polymeric micelle of the A(3)B-type lactosome was therefore found to be effective as a vehicle of In-111 to be targeted to meningeal dissemination and bone metastasis.