title: One-year follow-up of transgene expression by integrase-defective lentiviral vectors and their therapeutic potential in spinocerebellar ataxia model mice.
abstract: We examined integrase-defective lentiviral vectors (IDLVs) with a mutant (D64V) integrase in terms of their residual integration capability, the levels and duration of transgene expression and their therapeutic potential in comparison to wild-type lentiviral vectors (WTLVs) with a wild-type integrase gene. Compared with WTLVs, the IDLV-mediated proviral integration into host-cell chromosomes was approximately 1/3850 in HeLa cells and approximately 1/111 in mouse cerebellar neurons in vivo. At 2 months, transgene expression by IDLVs in the mouse cerebellum was comparable to that by WTLVs, but then significantly decreased. The mRNA levels at 6 and 12 months after injection in IDLV-infected cerebella were approximately 26% and 5%, respectively, of the mRNA levels in WTLV-injected cerebella. To examine the therapeutic potential, IDLVs or WTLVs expressing a molecule that enhances the ubiquitin-proteasome pathway were injected into the cerebella of spinocerebellar ataxia type 3 model mice (SCA3 mice). IDLV-injected SCA3 mice showed a significantly improved rotarod performance even at 1 year after-injection. Immunohistochemistry at 1 year after injection showed a drastic reduction of mutant aggregates in Purkinje cellsfrom IDLV-injected, as well as WTLV-injected, SCA3 mice. Our results suggest that because of the substantially reduced risk of insertional mutagenesis, IDLVs are safer and potentially effective as gene therapy vectors.
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Saida
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Matsuzaki
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Takayama
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Iizuka
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Konno
authors.affiliation: Laboratory of Molecular Biochemistry, Graduate School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yanagi
authors.affiliation: Department of Neurophysiology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hirai
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000378:metabolism* / Q000821:virology; D004195:Disease Models, Animal; D005500:Follow-Up Studies; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism; D005822:Genetic Vectors / Q000008:administration & dosage; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D019426:Integrases / Q000235:genetics* / Q000378:metabolism; D016086:Lentivirus / Q000235:genetics*; D051379:Mice; D009154:Mutation; D045442:Rotarod Performance Test; D015398:Signal Transduction; D020754:Spinocerebellar Ataxias / Q000628:therapy*; D019076:Transgenes
chemical_list: D019426:Integrases; C530558:CRAG protein, mouse; D020558:GTP Phosphohydrolases