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- Berglin-Enquist, Ida
(författare)
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Development of Mouse Models and Gene Therapy for Gaucher Disease
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Gaucher disease (GD) patients cannot metabolize glycosphingolipids properly due to deficiency of the enzyme glucosylceramidase (GCase). The lack of animal model for GD has hindered comprehensive investigation of disease mechanisms and also the development of curative treatment strategies such as hematopoietic stem cell (HSC) targeted gene therapy. Previous GCase deficient mice have either been lethal (due to disruption of the skin-barrier) or viable but without relevant symptoms of GD. We applied conditional strategies to create two different mouse models of GD, importantly sparing GCase activity in the skin during fetal development. Using the cre/loxP system and the Mx1-cre mouse we could develop an inducible mouse model with pathology and symptoms similar to type 1 GD patients, including infiltration of disease-characteristic Gaucher cells in target tissues, splenomegaly and anemia. We further used this model to demonstrate that HSC targeted gene therapy can cure manifest type 1 GD. The unfortunate occurrence of leukemia in otherwise successful clinical gene therapy trials has called attention to safety and by using two different transplantation-assays we provide evidence that GD has the potential to successfully respond to reduced-risk gene therapy protocols. In the second model, the function of a GBA null allele could be restored in the skin through breeding onto the K14-cre mouse, in which cre expression is restricted to the basal layer of the epidermis. This model developed early onset and rapidly progressive neurodegeneration characteristic of the severe neuronopathic form of GD. In this model we also observed considerable microglia activation. Microglia activation has been demonstrated to play an important role in the pathogenesis of other neurodegenerative conditions. Using a second mouse model in which GCase deficiency was restricted to neurons and macroglia we could demonstrate that the GCase deficient miroglia have a modulating role on disease onset and progression but are not the primary determinant of the severe neurodegeneration. Taken together the work described in this thesis provide the essential tools and proof-of-principle basis to proceed towards enhanced understanding of pathological mechanisms as well as development of novel treatment-modalities including HSC targeted gene therapy.
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| 3. |
- Berglin-Enquist, Ida, et al.
(författare)
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Murine models of acute neuronopathic Gaucher disease
- 2007
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 104:44, s. 17483-17488
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Tidskriftsartikel (refereegranskat)abstract
- Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by mutations in the glucosidase, beta, acid (GBA) gene that encodes the lysosomal enzyme glucosylceramidase (GCase). GCase deficiency leads to characteristic visceral pathology and, in some patients, lethal neurological manifestations. Here, we report the generation of mouse models with the severe neuronopathic form of GD. To circumvent the lethal skin phenotype observed in several of the previous GCase-deficient animals, we genetically engineered a mouse model with strong reduction in GCase activity in all tissues except the skin. These mice exhibit rapid motor dysfunction associated with severe neurodegeneration and apoptotic cell death within the brain, reminiscent of neuronopathic GD. In addition, we have created a second mouse model, in which GCase deficiency is restricted to neural and glial cell progenitors and progeny. These mice develop similar pathology as the first mouse model, but with a delayed onset and slower disease progression, which indicates that GCase deficiency within microglial cells that are of hematopoietic origin is not the primary determinant of the CNS pathology. These findings also demonstrate that normal microglial cells cannot rescue this neurodegenerative disease. These mouse models have significant implications for the development of therapy for patients with neuronopathic GD.
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| 4. |
- Berglin-Enquist, Ida, et al.
(författare)
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Successful Low-Risk Hematopoietic Cell Therapy in a Mouse Model of Type 1 Gaucher Disease
- 2009
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Ingår i: Stem Cells. - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 27:3, s. 744-752
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Tidskriftsartikel (refereegranskat)abstract
- Hematopoietic stem cell-based gene therapy offers the possibility of permanent correction for genetic disorders of the hematopoietic system. However, optimization of present protocols is required before gene therapy can be safely applied as general treatment of genetic diseases. In this study we have used a mouse model of type 1 Gaucher disease (GD) to demonstrate the feasibility of a low-risk conditioning regimen instead of standard radiation, which is associated with severe adverse effects. We first wanted to establish what level of engraftment and glucosylceramidase (GCase) activity is required to correct the pathology of the type 1 GD mouse. Our results demonstrate that a median wild-type (WT) cell engraftment of 7%, corresponding to GCase activity levels above 10 nmoles/hour and mg protein, was sufficient to reverse pathology in bone marrow and spleen in the GD mouse. Moreover, we applied nonmyeloablative doses of busulfan as a pretransplant conditioning regimen and show that even WT cell engraftment in the range of 1%-10% can confer a beneficial therapeutical outcome in this disease model. Taken together, our data provide encouraging evidence for the possibility of developing safe and efficient conditioning protocols for diseases that require only a low level of normal or gene-corrected cells for a permanent and beneficial therapeutic outcome. STEM CELLS 2009; 27: 744-752
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| 5. |
- Berglin-Enquist, Ida, et al.
(författare)
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Successful low-risk hematopoietic cell therapy in a mouse model of type 1 Gaucher disease.
- 2008
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Ingår i: - : Mary Ann Liebert Inc. ; , s. 1189-1190
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Konferensbidrag (refereegranskat)abstract
- Hematopoietic stem cell (HSC) based gene therapy offers the possibility of permanent correction for genetic disorders of the hematopoietic system. However, optimization of present protocols is required before gene therapy can be safely applied as general treatment of genetic diseases. In this study we have used a mouse model of type 1 Gaucher disease (GD) to demonstrate the feasibility of a low-risk conditioning regimen instead of standard radiation, which is associated with severe adverse effects. We first wanted to establish what level of engraftment and glucosylceramidase (GCase) activity is required to correct the pathology of the type 1 GD mouse. Our results demonstrate that a median WT cell engraftment of 7 % corresponding to GCase activity levels above 10 nmol/hr and mg protein was sufficient to reverse pathology within bone marrow (BM) and spleen in the GD mouse. Moreover, we applied non-myeloablative doses of busulphan as a pretransplant conditioning regimen and show that even WT cell engraftment in the range of 1-10% can confer a beneficial therapeutical outcome in this disease model. Taken together, our data provide encouraging evidence for the possibility to develop safe and efficient conditioning protocols for diseases that only require a low level of normal or gene corrected cells for a permanent and beneficial therapeutic outcome. ______________________________________________________________________________ Author contributions: I.B.E.: Conception and design, collection and assembly of data, data analysis and interpretation, manuscript writing; E.N.: Collection of data, data analysis and interpretation; J.-E.M.: Collection and assembly of data, data analysis and interpretation; M.E.: Collection and assembly of data, data analysis and interpretation; J.R.: Data analysis and interpretation, manuscript writing; S.K.: Conception and design, financial support, data analysis and interpretation, manuscript writing, final approval of manuscript.
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| 6. |
- Burke, Derek G., et al.
(författare)
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Increased glucocerebrosidase (GBA) 2 activity in GBA1 deficient mice brains and in Gaucher leucocytes
- 2013
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Ingår i: Journal of Inherited Metabolic Disease. - : Wiley. - 0141-8955 .- 1573-2665. ; 36:5, s. 869-872
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Tidskriftsartikel (refereegranskat)abstract
- Lysosomal glucocerebrosidase (GBA1) deficiency is causative for Gaucher disease. Not all individuals with GBA1 mutations develop neurological involvement raising the possibility that other factors may provide compensatory protection. One factor may be the activity of the non-lysosomal beta-glucosidase (GBA2) which exhibits catalytic activity towards glucosylceramide and is reported to be highly expressed in brain tissue. Here, we assessed brain GBA2 enzymatic activity in wild type, heterozygote and GBA1 deficient mice. Additionally, we determined activity in leucocytes obtained from 13 patients with Gaucher disease, 10 patients with enzymology consistent with heterozygote status and 19 controls. For wild type animals, GBA2 accounted for over 85 % of total brain GBA activity and was significantly elevated in GBA1 deficient mice when compared to heterozygote and wild types (GBA1 deficient; 92.4 +/- 5.6, heterozygote; 71.5 +/- 2.4, wild type 76.8 +/- 5.1 nmol/h/mg protein). For the patient samples, five Gaucher patients had GBA2 leucocyte activities markedly greater than controls. No difference in GBA2 activity was apparent between the control and carrier groups. Undetectable GBA2 activity was identified in four leucocyte preparations; one in the control group, two in the carrier group and one from the Gaucher disease group. Work is now required to ascertain whether GBA2 activity is a disease modifying factor in Gaucher disease and to identify the mechanism(s) responsible for triggering increased GBA2 activity in GBA1 deficiency states.
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| 7. |
- Farfel-Becker, Tamar, et al.
(författare)
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No evidence for activation of the unfolded protein response in neuronopathic models of Gaucher disease
- 2009
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 18:8, s. 1482-1488
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Tidskriftsartikel (refereegranskat)abstract
- Gaucher disease (GD), the most common lysosomal storage disorder (LSD), is caused by defects in the activity of the lysosomal enzyme, glucocerebrosidase, resulting in intracellular accumulation of glucosylceramide (GlcCer). Neuronopathic forms, which comprise only a small percent of GD patients, are characterized by neurological impairment and neuronal cell death. Little is known about the pathways leading from GlcCer accumulation to neuronal death or dysfunction but defective calcium homeostasis appears to be one of the pathways involved. Recently, endoplasmic reticulum stress together with activation of the unfolded protein response (UPR) has been suggested to play a key role in cell death in neuronopathic forms of GD, and moreover, the UPR was proposed to be a common mediator of apoptosis in LSDs (Wei et al. (2008) Hum. Mol. Genet. 17, 469-477). We now systematically examine whether the UPR is activated in neuronal forms of GD using a selection of neuronal disease models and a combination of western blotting and semi-quantitative and quantitative real-time polymerase chain reaction. We do not find any changes in either protein or mRNA levels of a number of typical UPR markers including BiP, CHOP, XBP1, Herp and GRP58, in either cultured Gaucher neurons or astrocytes, or in brain regions from mouse models, even at late symptomatic stages. We conclude that the proposition that the UPR is a common mediator for apoptosis in all neurodegenerative LSDs needs to be re-evaluated.
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