Gene therapy in the central nervous system: direct versus indirect gene delivery

Over the last decade, the combination of molecular biology and cell transplantation techniques has given rise to a powerful method for gene therapy. The implantation of genetically modified cultured cells has been extensively used in the central nervous system (CNS) in various experimental models of neurologic disorders. More recently, viral and chemical methods have been developed to further efforts to shuttle transgenes into the relatively inaccessible brain. Adenoviral and liposomal synthetic vectors carry transgenes into neural tissue in situ and are beginning to show promise as new methods for CNS therapy.