Epidermis: an attractive target tissue for gene therapy.

Important advances have been made within the past several years in understanding diseases at the molecular and cellular levels, which may enable the application of somatic gene therapy to a wide variety of genetic and acquired diseases. The initial clinical trials involving somatic gene therapy have demonstrated that gene transfer into human subjects can be performed safely and with public acceptance. This review focuses on use of the epidermis as a target tissue for gene therapy and assesses various delivery systems for both ex vivo and in vivo approaches. In addition, we discuss candidate diseases that may be amenable to epidermal gene therapy and the advantages of employing transgenic mouse model systems to test the efficacy of a given gene therapy prior to clinical trials.