Abstract
Mucopolysaccharidosis type I (MPS-I or Hurler syndrome) is an inherited deficiency of the lysosomal glycosaminoglycan (GAG)-degrading enzyme α-l-iduronidase (IDUA) in which GAG accumulation causes progressive multi-system dysfunction and death. Early allogeneic hematopoietic stem cell transplantation (HSCT) ameliorates clinical features and extends life but is not available to all patients, and inadequately corrects its most devastating features including mental retardation and skeletal deformities. To test novel therapies, we characterized an immunodeficient MPS-I mouse model less likely to develop immune reactions to transplanted human or gene-corrected cells or secreted IDUA. In the liver, spleen, heart, lung, kidney and brain of NOD/SCID/MPS-I mice IDUA was undetectable, and reduced to half in heterozygotes. MPS-I mice developed marked GAG accumulation (3-38-fold) in these organs. Neuropathological examination showed GM3 ganglioside accumulation in the striatum, cerebral peduncles, cerebellum and ventral brainstem of MPS-I mice. Urinary GAG excretion (6.5-fold higher in MPS-I mice) provided a non-invasive and reliable method suitable for serially following the biochemical efficacy of therapeutic interventions. We identified and validated using rigorous biostatistical methods, a highly reproducible method for evaluating sensorimotor function and motor skills development. This Rotarod test revealed marked abnormalities in sensorimotor integration involving the cerebellum, striatum, proprioceptive pathways, motor cortex, and in acquisition of motor coordination. NOD/SCID/MPS-I mice exhibit many of the clinical, skeletal, pathological and behavioral abnormalities of human MPS-I, and provide an extremely suitable animal model for assessing the systemic and neurological effects of human stem cell transplantation and gene therapeutic approaches, using the above techniques to measure efficacy.
Original language | English (US) |
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Pages (from-to) | 429-438 |
Number of pages | 10 |
Journal | Brain Research Bulletin |
Volume | 74 |
Issue number | 6 |
DOIs | |
State | Published - Nov 1 2007 |
Bibliographical note
Funding Information:The authors thank Dr. Elizabeth F. Neufeld, Professor and Chair, Department of Biological Chemistry, University of California Los Angeles, Los Angeles, CA, for help and advice with the biochemical assays used in this work. This work was supported by NIH R01-NS-48606 (P.G. and W.C.L.), the US Department of Veterans Affairs (P.G.) and the Childrens Cancer Research Fund (P.G.).
Keywords
- Animal model
- Ganglioside
- Glycosaminoglycans
- Iduronidase
- Mice
- Mucopolysaccharidosis I
- Rotarod performance test
- Stem cell