1080. Receptor-Targeting Smart Vectors for Efficient Gene Transfer to Tumours

We seek to develop novel synthetic vector formulations that can be administered systemically to target therapeutic genes to tumours. Cationic nonviral vectors are cleared rapidly from the circulation by the reticuloendothelial system as a result of binding to plasma proteins and vector aggregation. Circulation times may be extended by shielding the vectors with polyethylene glycol (PEG) moieties. However, PEGylation often leads to greatly reduced transfection efficiency due to excessive vector stability. The aim of this project was to develop novel formulations of PEGylated vectors which may be administered intravenously (i. v.), and persist in the circulationand target tumour-associated receptors. The vector has been further modified to disassemble within the cell in response to the intracellular environment to achieve high transfection efficiency. Such virus-like vector formulations are often referred to as |[ldquo]|smart vectors|[rdquo]|.