HEPATIC GENE-THERAPY - EFFICIENT GENE DELIVERY AND EXPRESSION IN PRIMARY HEPATOCYTES UTILIZING A CONJUGATED ADENOVIRUS-DNA COMPLEX

Receptor-mediated endocytosis is an effective method for gene delivery into target cells. We have previously shown that DNA molecules comple xed with asialoglycoprotein can be efficiently endocytosed by primary hepatocytes and the internalized DNA can be released from endosomes by the use of a replication-defective adenovirus. Because the DNA and vi rus enter target cells independently, activity enhancement requires hi gh concentrations of adenoviral particles. In this study, adenoviral p articles were chemically conjugated to poly(L-lysine) and bound ionica lly to DNA molecules. Quantitative delivery to primary hepatocytes was achieved with significantly reduced viral titer when the asialoorosom ucoid-poly(L-lysine) conjugate was included in the complex. The conjug ated adenovirus was used to deliver a DNA vector containing canine fac tor IX to mouse hepatocytes, resulting in the expression of significan t concentrations of canine factor IX in the culture medium. The result s suggest that receptor-mediated endocytosis coupled with an efficient endosomal lysis vector should permit the application of targeted and efficient gene delivery into the liver for gene therapy of hepatic def iciencies.