ENHANCEMENT OF GENE DELIVERY BY LISTERIOLYSIN O/PROTAMINE/PLASMID DNA COMPLEX

摘要

Listeriolysin O (LLO), an endosomolytic protein from Listeria monocytogenes, was exploited in plasmid DNA delivery. The single cysteine of LLO was conjugated to protamine via a disufide bond. LLO-s-s-protamine was hemolytically active only when LLO was released from protamine upon reduction of the cysteine. Complexes containing plasmid DNA, protamine, and LLO-s-s-protamine were tested for their enhanced gene delivery efficiency in in vitro transfection experiments using luciferase and GFP reporter genes. Replacing up to 1% of protamine with LLO-s-s-protamine resulted in close to 3 orders of magnitude improvement in luciferase gene expression over protamine/DNA complexes.