PEG-PE/phosphatidylcholine mixed immunomicelles specifically deliver encapsulated taxol to tumor cells of different origin and promote their efficient killing.

Mixed micelles were prepared from poly(ethyleneglycol)-distearyl phosphoethanolamine (PEG2000-PE) and egg phosphatidylcholine. The micelles were covalently modified with the nucleosome-specific monoclonal antibody 2C5 known to recognize and bind a variety of tumor cells via their surface-bound nucleosomes. Covalent attachment of 2C5 antibody was performed via a micelle-incorporated PEG-PE with the distal terminus of the PEG block activated with p-nitrophenylcarbonyl group (pNP-PEG-PE). Micelle surface-attached 2C5 antibody maintained its specific activity. 2C5-targeted immunomicelles were able to carry more than 3 wt% of taxol. Taxol-loaded immunomicelles specifically recognized tumor cell lines of several types. The cytotoxicity of 2C5-targeted taxol-loaded immunomicelles in a cell culture model was much higher when compared with free taxol or taxol in non-targeted micelles.