RESUMEN
Background: Mucopolysaccharidosis type I-Hurler (MPS1-H) is a severe genetic lysosomal storage disorder due to loss-of-function mutations in the IDUA gene. The subsequent complete deficiency of alpha l-iduronidase enzyme is directly responsible of a progressive accumulation of glycosaminoglycans (GAG) in lysosomes which affects the functions of many tissues. Consequently, MPS1 is characterized by systemic symptoms (multiorgan dysfunction) including respiratory and cardiac dysfunctions, skeletal abnormalities and early fatal neurodegeneration. Methods: To understand mechanisms underlying MPS1 neuropathology, we generated induced pluripotent stem cells (iPSC) from a MPS1-H patient with loss-of-function mutations in both IDUA alleles. To avoid variability due to different genetic background of iPSC, we established an isogenic control iPSC line by rescuing IDUA expression by a lentivectoral approach. Results: Marked differences between MPS1-H and IDUA-corrected isogenic controls were observed upon neural differentiation. A scratch assay revealed a strong migration defect of MPS1-H cells. Also, there was a massive impact of IDUA deficiency on gene expression (340 genes with an FDR <0.05). Conclusions: Our results demonstrate a hitherto unknown connection between lysosomal degradation, gene expression and neural motility, which might account at least in part for the phenotype of MPS1-H patients.
Asunto(s)
Movimiento Celular/genética , Células Madre Pluripotentes Inducidas/metabolismo , Mucopolisacaridosis I/metabolismo , Neuronas/metabolismo , Diferenciación Celular/genética , Células Cultivadas , Expresión Génica/genética , Glicosaminoglicanos/genética , Glicosaminoglicanos/metabolismo , Humanos , Iduronidasa/genética , Iduronidasa/metabolismo , Lisosomas/genética , Lisosomas/metabolismo , Mucopolisacaridosis I/genética , Mutación/genética , FenotipoRESUMEN
Mucopolysaccharidosis type I-Hurler (MPS1-H) is the most severe form of inherited metabolic diseases caused by mutations in the IDUA gene. The resulting deficiency of alpha L-iduronidase enzyme leads to a progressive accumulation of glycosaminoglycans in lysosomes which damages multiple organs and highly reduces life expectancy of affected children. Skin fibroblasts of a 2-year-old MPS1-H male, carrying two mutations in each IDUA alleles (H358_T364del; W402X), were reprogrammed into induced pluripotent stem cells (iPSCs) using the CytoTune-iPS Sendai Reprogramming method applying Yamanaka-factors (OCT4, SOX2, KLF4, c-MYC). iPSCs expressed pluripotency transcription factors while iPSC-derived embryoid bodies reveal markers of the three germ layers.