Engineered human tmpk/AZT as a novel enzyme/prodrug axis for suicide gene therapy. Mol Ther 2007 May;15(5):962-70
Date
03/22/2007Pubmed ID
17375075DOI
10.1038/mt.sj.6300122Scopus ID
2-s2.0-34247194881 (requires institutional sign-in at Scopus site) 87 CitationsAbstract
Gene therapy and stem cell transplantation safety could be enhanced by control over the fate of therapeutic cells. Suicide gene therapy uses enzymes that convert prodrugs to cytotoxic entities; however, heterologous moieties with poor kinetics are employed. We describe a novel enzyme/prodrug combination for selectively inducing apoptosis in lentiviral vector-transduced cells. Rationally designed variants of human thymidylate kinase (tmpk) that effectively phosphorylate 3'-azido-3'-deoxythymidine (AZT) were efficiently delivered. Transduced Jurkat cell lines were eliminated by AZT. We demonstrate that this schema targeted both dividing and non-dividing cells, with a novel killing mechanism involving apoptosis induction via disruption of the mitochondrial inner membrane potential and activation of caspase-3. Primary murine and human T cells were also transduced and responded to AZT. Furthermore, low-dose AZT administration to non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice injected with transduced K562 cells suppressed tumor growth. This novel suicide gene therapy approach can thus be integrated as a safety switch into therapeutic vectors.
Author List
Sato T, Neschadim A, Konrad M, Fowler DH, Lavie A, Medin JAAuthor
Jeffrey A. Medin PhD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAntigens, CD19
Antimetabolites
Apoptosis
Blotting, Western
Caspase 3
Cell Line, Tumor
Chromatography, High Pressure Liquid
Female
Flow Cytometry
Genes, Transgenic, Suicide
Genetic Therapy
Genetic Vectors
Humans
Jurkat Cells
K562 Cells
Male
Mice
Mice, Inbred NOD
Mice, SCID
Nucleoside-Phosphate Kinase
Prodrugs
T-Lymphocytes
Transfection
Zidovudine
