HSV Amplicons in Gene Therapy

Herpes simplex virus (HSV) amplicons are defective virus vectors capable of introducing amplified foreign genes into variable types of eukaryotic cells, such as fibroblasts, macrophages, glia, and neurons in different organisms including rodents, monkeys, and human (refs. 1 –3 ; reviewed in ref. 4 ). The defective viruses follow their nondefective counterparts in the ability to infect mitotic, as well as postmitotic cells. This makes them potentially useful vectors for use in nondividing cells, such as in nerve cells. Available retrovirus vectors employed to date for gene therapy require cell division and therefore cannot be used to target neurons.