Herpesviruses: expression of genes in postmitotic brain cells

Gene transfer into neural cells in the adult mammalian brain using vectors derived from the herpes simplex virus HSV-1 has great promise both for elucidating neuronal physiology and brain mechanisms, and for gene therapy of neurological diseases. Two kinds of HSV-1 vectors are being explored: first, defective HSV-1 vectors are small plasmids containing essential HSV-1 cis-acting functions that use HSV-1 mutants as helper virus for packaging; and second, vectors that contain a recombinant gene inserted into the HSV-1 genome. Recently, several genes that alter neuronal physiology have been expressed from defective HSV-1 vectors, both in cultured neurons and in vivo.