Retroviruses: delivery vehicle to the liver.

Liver-directed gene therapy holds great promise for the treatment of inherited metabolic disease. Two strategies have emerged. Ex vivo gene therapy involves the transplantation of autologous hepatocytes transduced with recombinant retroviruses while in culture. The feasibility of this approach has been demonstrated in several animal models, and a human trial has been initiated. An alternative strategy uses recombinant viruses to deliver the transgene directly to hepatocytes in vivo.