Gene therapy for human liver diseases

The liver can be considered an ideal target to design gene therapy strategies because of the unique properties of hepatic cells. The great amount of work carried out in this field clearly delineates the quality of the new approaches that have been developed in the last few years and demonstrates the feasibility of this strategy in a wide range of multi-factorial and inherited disorders. However, improvement of current vectors to specifically and efficiently deliver the therapeutic gene into the target cell remains a daunting problem. In this review, we will summarize the most important approaches that are currently under investigation, the pathological conditions that can be treated by this strategy and the most important drawbacks that remain to be overcome in order to achieve long-term and high-level gene expression.