title: Retroviral-vector-mediated gene therapy to mucopolysaccharidosis I mice improves sensorimotor impairments and other behavioral deficits.
abstract: Mucopolysaccharidosis I (MPS I) is a lysosomal storage disease due to α-L-iduronidase (IDUA) deficiency that results in the accumulation of glycosaminoglycans (GAG). Systemic gene therapy to MPS I mice can reduce lysosomal storage in the brain, but few data are available regarding the effect upon behavioral function. We investigated the effect of gene therapy with a long-terminal-repeat (LTR)-intact retroviral vector or a self-inactivating (SIN) vector on behavioral function in MPS I mice. The LTR vector was injected intravenously to 6-week-old MPS I mice, and the SIN vector was given to neonatal or 6-week-old mice. Adult-LTR, neonatal-SIN, and adult-SIN-treated mice achieved serum IDUA activity of 235 ± 20 (84-fold normal), 127 ± 10, and 71 ± 7 U/ml, respectively. All groups had reduction in histochemical evidence of lysosomal storage in the brain, with the adult-LTR group showing the best response, while adult-LTR mice had reductions in lysosomal storage in the cristae of the vestibular system. Behavioral evaluation was performed at 8 months. Untreated MPS I mice had a markedly reduced ability to hold onto an inverted screen or climb down a pole. LTR-vector-treated mice had marked improvements on both of these tests, whereas neonatal-SIN mice showed improvement in the pole test. We conclude that both vectors can reduce brain disease in MPS I mice, with the LTR vector achieving higher serum IDUA levels and better correction. Vestibular abnormalities may contribute to mobility problems in patients with MPS I, and gene therapy may reduce symptoms.
authors.affiliation: Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Guilherme
authors.initials: G
authors.lastname: Baldo
authors.forename: David F
authors.initials: DF
authors.lastname: Wozniak
authors.forename: Kevin K
authors.initials: KK
authors.lastname: Ohlemiller
authors.forename: Yanming
authors.initials: Y
authors.lastname: Zhang
authors.forename: Roberto
authors.initials: R
authors.lastname: Giugliani
authors.forename: Katherine P
authors.initials: KP
authors.lastname: Ponder
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal / Q000502:physiology; D001921:Brain / Q000201:enzymology / Q000378:metabolism; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D007068:Iduronidase / Q000235:genetics*; D001523:Mental Disorders / Q000209:etiology / Q000235:genetics / Q000517:prevention & control*; D051379:Mice; D008810:Mice, Inbred C57BL; D016472:Motor Neuron Disease / Q000209:etiology / Q000517:prevention & control*; D009046:Motor Neurons / Q000502:physiology; D008059:Mucopolysaccharidosis I / Q000150:complications / Q000628:therapy*; D012190:Retroviridae
chemical_list: D007068:Iduronidase