title: An approach to achieve long-term expression in skin gene therapy.
abstract: For gene therapy purposes, the skin is an attractive organ to target for systemic delivery of therapeutic proteins to treat systemic diseases, skin diseases, or skin cancer. To achieve long-term stable expression of a therapeutic gene in keratinocytes (KC), we have developed an approach using a bicistronic retroviral vector expressing the desired therapeutic gene linked to a selectable marker (multidrug resistant gene, MDR) that is then introduced into KC and fibroblasts (FB) to create genetically modified human skin equivalent (HSE). After grafting the HSE onto immunocompromised mice, topical colchicine treatment is used to select and enrich for genetically modified keratinocyte stem cells (KSC) that express MDR and are resistant to colchicine's antimitotic effects. Both the apparatus for topical colchicine delivery and the colchicine doses have been optimized for application to human skin. This approach can be validated by systemic delivery of therapeutic factors such as erythropoietin and the antihypertensive atrial natriuretic peptide.
authors.affiliation: Dermatology Branch, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20892-1908, USA. therriej@mail.nih.gov
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Therrien
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Pfützner
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Vogel
mesh_terms: D000818:Animals; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D015870:Gene Expression; D018014:Gene Transfer Techniques; D019450:Genes, MDR; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism*; D012867:Skin / Q000166:cytology / Q000378:metabolism*; D012873:Skin Diseases, Genetic / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D019076:Transgenes / Q000235:genetics