title: Treatment of the mouse model of mucopolysaccharidosis type IIIB with lentiviral-NAGLU vector.
abstract: The Sanfilippo syndrome type B (mucopolysaccharidosis IIIB) is an autosomal recessive disorder due to mutations in the gene encoding NAGLU (alpha-N-acetylglucosaminidase), one of the enzymes required for the degradation of the GAG (glycosaminoglycan) heparan sulphate. No therapy exists for affected patients. We have shown previously the efficacy of lentiviral-NAGLU-mediated gene transfer in correcting in vitro the defect on fibroblasts of patients. In the present study, we tested the therapy in vivo on a knockout mouse model using intravenous injections. Mice (8-10 weeks old) were injected with one of the lentiviral doses through the tail vein and analysed 1 month after treatment. A single injection of lentiviral-NAGLU vector resulted in transgene expression in liver, spleen, lung and heart of treated mice, with the highest level reached in liver and spleen. Expression of 1% normal NAGLU activity in liver resulted in a 77% decrease in the GAG content; more remarkably, an expression of 0.16% normal activity in lung was capable of decreasing the GAG level by 29%. Long-term (6 months) follow up of the gene therapy revealed that the viral genome integration persisted in the target tissues, although the real-time PCR analysis showed a decrease in the vector DNA content with time. Interestingly, the decrease in GAG levels was maintained in liver, spleen, lung and heart of treated mice. These results show the promising potential and the limitations of lentiviral-NAGLU vector to deliver the human NAGLU gene in vivo.
authors.affiliation: Department of Biochemistry and Medical Biotechnologies, University of Naples Federico II, Via S. Pansini n. 5, 80131 Naples, Italy. dinatale@unina.it
authors.forename: Paola
authors.initials: P
authors.lastname: Di Natale
authors.forename: Carmela
authors.initials: C
authors.lastname: Di Domenico
authors.forename: Nadia
authors.initials: N
authors.lastname: Gargiulo
authors.forename: Sigismondo
authors.initials: S
authors.lastname: Castaldo
authors.forename: Enrico
authors.initials: E
authors.lastname: Gonzalez Y Reyero
authors.forename: Pratibha
authors.initials: P
authors.lastname: Mithbaokar
authors.forename: Mario
authors.initials: M
authors.lastname: De Felice
authors.forename: Antonia
authors.initials: A
authors.lastname: Follenzi
authors.forename: Luigi
authors.initials: L
authors.lastname: Naldini
authors.forename: Guglielmo R D
authors.initials: GR
authors.lastname: Villani
mesh_terms: D000118:Acetylglucosaminidase / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D003587:Cytomegalovirus; D004195:Disease Models, Animal; D015316:Genetic Therapy; D005822:Genetic Vectors; D016679:Genome, Viral; D006025:Glycosaminoglycans / Q000378:metabolism; D016086:Lentivirus; D051379:Mice; D008817:Mice, Mutant Strains; D009084:Mucopolysaccharidosis III / Q000201:enzymology / Q000235:genetics / Q000628:therapy*; D010641:Phenotype; D011401:Promoter Regions, Genetic; D013997:Time Factors; D014018:Tissue Distribution; D014161:Transduction, Genetic
chemical_list: D006025:Glycosaminoglycans; C033079:alpha-N-acetyl-D-glucosaminidase; D000118:Acetylglucosaminidase