Herpes simplex virus‐based vectors

Summary Herpes simplex virus (HSV)‐based vectors have primarily been developed for neuronal gene delivery, taking advantage of the virus' natural neurotropism. Two types of vector are available: replication defective viruses, whose cytotoxicity has been abolished by deleting viral gene products, and amplicon vectors, which are plasmids packaged into HSV particles with the aid of a helper virus. In this review I discuss how the cytotoxicity of the wild‐type virus has been abolished, the progress which has been made toward defining promoter elements capable of directing long‐term transgene expression form the latent viral genome and some of the potential clinical uses of these versatile vectors.