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Francisco AF, Sousa GR, Vaughan M, Langston H, Khan A, Jayawardhana S, Taylor MC, Lewis MD, Kelly JM. Cardiac Abnormalities in a Predictive Mouse Model of Chagas Disease. Pathogens 2023; 12:1364. [PMID: 38003828 PMCID: PMC10674564 DOI: 10.3390/pathogens12111364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/09/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
Chronic Chagas cardiomyopathy (CCC) results from infection with the protozoan parasite Trypanosoma cruzi and is a prevalent cause of heart disease in endemic countries. We previously found that cardiac fibrosis can vary widely in C3H/HeN mice chronically infected with T. cruzi JR strain, mirroring the spectrum of heart disease in humans. In this study, we examined functional cardiac abnormalities in this host:parasite combination to determine its potential as an experimental model for CCC. We utilised electrocardiography (ECG) to monitor T. cruzi-infected mice and determine whether ECG markers could be correlated with cardiac function abnormalities. We found that the C3H/HeN:JR combination frequently displayed early onset CCC indicators, such as sinus bradycardia and right bundle branch block, as well as prolonged PQ, PR, RR, ST, and QT intervals in the acute stage. Our model exhibited high levels of cardiac inflammation and enhanced iNOS expression in the acute stage, but denervation did not appear to have a role in pathology. These results demonstrate the potential of the C3H/HeN:JR host:parasite combination as a model for CCC that could be used for screening new compounds targeted at cardiac remodelling and for examining the potential of antiparasitic drugs to prevent or alleviate CCC development and progression.
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Affiliation(s)
- Amanda Fortes Francisco
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Giovane R. Sousa
- Harvard Medical School, Section on Immunobiology, Joslin Diabetes Center, 1 Joslin Place, Boston, MA 02215, USA
| | - Mhairi Vaughan
- Research Department of Haematology, Cancer Institute, Faculty of Medical Sciences, University College London, London WC1E 6DD, UK
| | - Harry Langston
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Archie Khan
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Shiromani Jayawardhana
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
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Oakley RH, Cruz-Topete D, He B, Foley JF, Myers PH, Xu X, Gomez-Sanchez CE, Chambon P, Willis MS, Cidlowski JA. Cardiomyocyte glucocorticoid and mineralocorticoid receptors directly and antagonistically regulate heart disease in mice. Sci Signal 2019; 12:12/577/eaau9685. [PMID: 30992401 DOI: 10.1126/scisignal.aau9685] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Stress is increasingly associated with heart dysfunction and is linked to higher mortality rates in patients with cardiometabolic disease. Glucocorticoids are primary stress hormones that regulate homeostasis through two nuclear receptors, the glucocorticoid receptor (GR) and mineralocorticoid receptor (MR), both of which are present in cardiomyocytes. To examine the specific and coordinated roles that these receptors play in mediating the direct effects of stress on the heart, we generated mice with cardiomyocyte-specific deletion of GR (cardioGRKO), MR (cardioMRKO), or both GR and MR (cardioGRMRdKO). The cardioGRKO mice spontaneously developed cardiac hypertrophy and left ventricular systolic dysfunction and died prematurely from heart failure. In contrast, the cardioMRKO mice exhibited normal heart morphology and function. Despite the presence of myocardial stress, the cardioGRMRdKO mice were resistant to the cardiac remodeling, left ventricular dysfunction, and early death observed in the cardioGRKO mice. Gene expression analysis revealed the loss of gene changes associated with impaired Ca2+ handling, increased oxidative stress, and enhanced cell death and the presence of gene changes that limited the hypertrophic response and promoted cardiomyocyte survival in the double knockout hearts. Reexpression of MR in cardioGRMRdKO hearts reversed many of the cardioprotective gene changes and resulted in cardiac failure. These findings reveal a critical role for balanced cardiomyocyte GR and MR stress signaling in cardiovascular health. Therapies that shift stress signaling in the heart to favor more GR and less MR activity may provide an improved approach for treating heart disease.
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Affiliation(s)
- Robert H Oakley
- Signal Transduction Laboratory, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Diana Cruz-Topete
- Signal Transduction Laboratory, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Bo He
- Signal Transduction Laboratory, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Julie F Foley
- Cellular and Molecular Pathology Branch, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Page H Myers
- Comparative Medicine Branch, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Xiaojiang Xu
- Laboratory of Integrative Bioinformatics, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Celso E Gomez-Sanchez
- Endocrinology Division, G.V. (Sonny) Montgomery VA Medical Center, Jackson, MS 39216, USA.,Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Pierre Chambon
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS UMR7104, Inserm U964, Université de Strasbourg, Collège de France, Illkirch 67404, France
| | - Monte S Willis
- Department of Pathology and Laboratory Medicine, McAllister Heart Institute, UNC, Chapel Hill, NC 27599, USA
| | - John A Cidlowski
- Signal Transduction Laboratory, NIEHS, NIH, DHHS, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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Tomatsu S, Azario I, Sawamoto K, Pievani AS, Biondi A, Serafini M. Neonatal cellular and gene therapies for mucopolysaccharidoses: the earlier the better? J Inherit Metab Dis 2016; 39:189-202. [PMID: 26578156 PMCID: PMC4754332 DOI: 10.1007/s10545-015-9900-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/21/2015] [Accepted: 10/22/2015] [Indexed: 12/03/2022]
Abstract
Mucopolysaccharidoses (MPSs) are a group of lysosomal storage disorders (LSDs). The increasing interest in newborn screening procedures for LSDs underlines the need for alternative cellular and gene therapy approaches to be developed during the perinatal period, supporting the treatment of MPS patients before the onset of clinical signs and symptoms. The rationale for considering these early therapies results from the clinical experience in the treatment of MPSs and other genetic disorders. The normal or gene-corrected hematopoiesis transplanted in patients can produce the missing protein at levels sufficient to improve and/or halt the disease-related abnormalities. However, these current therapies are only partially successful, probably due to the limited efficacy of the protein provided through the hematopoiesis. An alternative explanation is that the time at which the cellular or gene therapy procedures are performed could be too late to prevent pre-existing or progressive organ damage. Considering these aspects, in the last several years, novel cellular and gene therapy approaches have been tested in different animal models at birth, a highly early stage, showing that precocious treatment is critical to prevent long-term pathological consequences. This review provides insights into the state-of-art accomplishments made with neonatal cellular and gene-based therapies and the major barriers that need to be overcome before they can be implemented in the medical community.
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Affiliation(s)
- Shunji Tomatsu
- Department of Biomedical Research, Alfred I. duPont Institute Hospital for Children, Wilmington, DE, USA.
- Skeletal Dysplasia Lab, Department of Biomedical Research, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE, 19899-0269, USA.
| | - Isabella Azario
- Dulbecco Telethon Institute at Centro Ricerca M. Tettamanti, Department of Paediatrics, University of Milano-Bicocca, San Gerardo Hospital, via Pergolesi, 33, 20900, Monza, MB, Italy
| | - Kazuki Sawamoto
- Department of Biomedical Research, Alfred I. duPont Institute Hospital for Children, Wilmington, DE, USA
| | - Alice Silvia Pievani
- Dulbecco Telethon Institute at Centro Ricerca M. Tettamanti, Department of Paediatrics, University of Milano-Bicocca, San Gerardo Hospital, via Pergolesi, 33, 20900, Monza, MB, Italy
| | - Andrea Biondi
- Centro Ricerca M. Tettamanti, Department of Paediatrics, University of Milano-Bicocca, Via Pergolesi, 33, Monza, 20900, Italy
| | - Marta Serafini
- Dulbecco Telethon Institute at Centro Ricerca M. Tettamanti, Department of Paediatrics, University of Milano-Bicocca, San Gerardo Hospital, via Pergolesi, 33, 20900, Monza, MB, Italy.
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Ariza L, Giménez-Llort L, Cubizolle A, Pagès G, García-Lareu B, Serratrice N, Cots D, Thwaite R, Chillón M, Kremer EJ, Bosch A. Central nervous system delivery of helper-dependent canine adenovirus corrects neuropathology and behavior in mucopolysaccharidosis type VII mice. Hum Gene Ther 2014; 25:199-211. [PMID: 24299455 DOI: 10.1089/hum.2013.152] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Canine adenovirus type 2 vectors (CAV-2) are promising tools to treat global central nervous system (CNS) disorders because of their preferential transduction of neurons and efficient retrograde axonal transport. Here we tested the potential of a helper-dependent CAV-2 vector expressing β-glucuronidase (HD-RIGIE) in a mouse model of mucopolysaccharidosis type VII (MPS VII), a lysosomal storage disease caused by deficiency in β-glucuronidase activity. MPS VII leads to glycosaminoglycan accumulation into enlarged vesicles in peripheral tissues and the CNS, resulting in peripheral and neuronal dysfunction. After intracranial administration of HD-RIGIE, we show long-term expression of β-glucuronidase that led to correction of neuropathology around the injection site and in distal areas. This phenotypic correction correlated with a decrease in secondary-elevated lysosomal enzyme activity and glycosaminoglycan levels, consistent with global biochemical correction. Moreover, HD-RIGIE-treated mice show significant cognitive improvement. Thus, injections of HD-CAV-2 vectors in the brain allow a global and sustained expression and may have implications for brain therapy in patients with lysosomal storage disease.
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Affiliation(s)
- Lorena Ariza
- 1 Center of Animal Biotechnology and Gene Therapy and Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona , 08193 Bellaterra, Barcelona, Spain
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Abstract
PRINCIPLE Mucopolysaccharidosis is an inborn error of metabolism causing glucosaminoglycans tissue storage. Cardiovascular involvement is variable but contributes significantly towards the morbidity and mortality of the patients. OBJECTIVE To characterise the echocardiographic abnormalities in children and adolescents with different types of mucopolysaccharidosis. METHOD Echocardiograms and medical records of 28 patients aged 2-14 years, seen from 2003 to 2005, were revised. At that time, the enzymatic replacement therapy was still not available in our institution. RESULTS Echocardiographic alterations were detected in 26 patients (93%), whereas 16 (57%) had abnormal auscultation, and only 6 (21%) presented with cardiovascular complaint. Mitral valve thickening with dysfunction (regurgitation, stenosis, or double lesion) was diagnosed in 60.8%, left ventricular hypertrophy in 43% and aortic valve thickening with regurgitation in 35.8% of the patients. There was no systolic dysfunction and mild left diastolic dysfunction was shown in 21.5% of the patients. Pulmonary hypertension was present in 36% of the patients, causing the only two deaths recorded. There was a strong association between the accumulation of dermatan sulphate and the presence of mitral valve dysfunction (p = 0.0003), aortic valve dysfunction (p = 0.006), and pulmonary hypertension (p = 0.006). Among individuals with two or more examinations, 82% had a worsening evolution. CONCLUSIONS Echocardiographic alterations in children with Mucopolysaccharidosis are frequent and have a progressive character. Left valve lesions, ventricular hypertrophy, and pulmonary hypertension were the most common findings and there was an association between the accumulation of dermatan sulphate and cardiovascular involvement. Unlike in adults, pulmonary hypertension was the main cause of death, not left ventricle systolic dysfunction.
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Woloszynek JC, Kovacs A, Ohlemiller KK, Roberts M, Sands MS. Metabolic adaptations to interrupted glycosaminoglycan recycling. J Biol Chem 2009; 284:29684-91. [PMID: 19700765 DOI: 10.1074/jbc.m109.020818] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lysosomal storage diseases (LSD) are metabolic disorders characterized by accumulation of undegraded material. The mucopolysaccharidoses (MPS) are LSDs defined by the storage of glycosaminoglycans. Previously, we hypothesized that cells affected with LSD have increased energy expenditure for biosynthesis because of deficiencies of raw materials sequestered within the lysosome. Thus, LSDs can be characterized as diseases of deficiency as well as overabundance (lysosomal storage). In this study, metabolite analysis identified deficiencies in simple sugars, nucleotides, and lipids in the livers of MPSI mice. In contrast, most amino acids, amino acid derivatives, dipeptides, and urea were elevated. These data suggest that protein catabolism, perhaps because of increased autophagy, is at least partially fulfilling intermediary metabolism. Thus, maintaining glycosaminoglycan synthesis in the absence of recycled precursors results in major shifts in the energy utilization of the cells. A high fat diet increased simple sugars and some fats and lowered the apparent protein catabolism. Interestingly, autophagy, which is increased in several LSDs, is responsive to dietary intervention and is reduced in MPSVII and MPSI mice fed a high fat diet. Although long term dietary treatment improved body weight in MPSVII mice, it failed to improve life span or retinal function. In addition, the ventricular hypertrophy and proximal aorta dilation observed in MPSVII mice were unchanged by a high fat, simple sugar diet. As the mechanism of this energy imbalance is better understood, a more targeted nutrient approach may yet prove beneficial as an adjunct therapy to traditional approaches.
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Affiliation(s)
- Josh C Woloszynek
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Donsante A, Levy B, Vogler C, Sands MS. Clinical response to persistent, low-level beta-glucuronidase expression in the murine model of mucopolysaccharidosis type VII. J Inherit Metab Dis 2007; 30:227-38. [PMID: 17308887 DOI: 10.1007/s10545-007-0483-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Revised: 12/20/2006] [Accepted: 12/21/2006] [Indexed: 12/28/2022]
Abstract
Mucopolysaccharidosis type VII (MPS VII) is a lysosomal storage disease caused by beta-glucuronidase (GUSB) deficiency. This disease exhibits a broad spectrum of clinical signs including skeletal dysplasia, retinal degeneration, cognitive deficits and hearing impairment. Sustained, high-level expression of GUSB significantly improves the clinical course of the disease in the murine model of MPS VII. Low levels of enzyme expression (1-5% of normal) can significantly reduce the biochemical and histopathological manifestations of MPS VII. However, it has not been clear from previous studies whether persistent, low levels of circulating GUSB lead to significant improvements in the clinical presentation of this disease. We generated a rAAV2 vector that mediates persistent, low-level GUSB expression in the liver. Liver and serum levels of GUSB were maintained at approximately 5% and approximately 2.5% of normal, respectively, while other tissue ranged from background levels to 0.9%. This level of activity significantly reduced the secondary elevations of alpha-galactosidase and the levels of glycosaminoglycans in multiple tissues. Interestingly, this level of GUSB was also sufficient to reduce lysosomal storage in neurons in the brain. Although there were small but statistically significant improvements in retinal function, auditory function, skeletal dysplasia, and reproduction in rAAV-treated MPS VII mice, the clinical deficits were still profound and there was no improvement in lifespan. These data suggest that circulating levels of GUSB greater than 2.5% will be required to achieve substantial clinical improvements in MPS VII.
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Affiliation(s)
- A Donsante
- Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri, USA
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Lessard MD, Alley TL, Proctor JL, Levy B, Galvin N, Vogler CA, Soper BW. Attenuation of murine lysosomal storage disease by allogeneic neonatal bone marrow transplantation using costimulatory blockade and donor lymphocyte infusion without myeloablation. Clin Immunol 2006; 119:166-79. [PMID: 16487752 DOI: 10.1016/j.clim.2005.12.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2005] [Revised: 12/21/2005] [Accepted: 12/28/2005] [Indexed: 01/09/2023]
Abstract
Treatment of nonmalignant childhood disorders by bone marrow transplantation (BMT) is limited by toxicity from preparatory regimens and immune consequences associated with engraftment of allogeneic donor cells. Using costimulatory blockade (anti-CD40L mAb and CTLA-4Ig) combined with high-dose BMT in nonablated neonates, we obtained engraftment and established tolerance using both partially MHC mismatched (H2g7 into H2b) and fully mismatched BM (H2s into H2b). Recipients were mucopolysaccharidosis type VII (MPS VII) mice with lysosomal storage disease in order to assess therapeutic outcome. Recipients treated with donor lymphocyte infusion (DLI) amplified microchimerism to full donor. Recipients without DLI maintained long-term engraftment, tolerance, and had extended life spans. DLI increased donor cell mediated replacement of beta-glucuronidase (GUSB) activity in all tissues and maintained clearance of lysosomes better than in non-DLI-treated mice. DLI amplification of partially mismatched BM and fully mismatched BM caused late onset chronic GvHD in 56% and 100% of recipients, respectively.
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Affiliation(s)
- Mark D Lessard
- The Jackson Laboratory, Box 95, 600 Main Street, Bar Harbor, ME 04609, USA
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Abstract
Bone marrow transplantation for lysosomal storage disorders has been used for the past 25 years. The early allure of a promising new therapy has given way to more realistic expectations, as it has become clear that bone marrow transplantation is not a cure, but merely ameliorates the clinical phenotype. The results in some disorders are more acceptable than in others. Significant challenges have emerged, particularly the poor mesenchymal and neurological responses. Important recent advances in lysosomal biology, both in health and disease, have helped us to better understand the results of bone marrow transplantation, and to rationalize its role in the treatment of lysosomal storage disorders alongside newer therapies. At the same time, they have helped researchers to explore new therapeutic applications of bone marrow cells, such as gene and stem cell therapy.
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Affiliation(s)
- Ashok Vellodi
- a Consultant Paediatrician and Honorary Reader, Great Ormond Street Hospital for Children, Metabolic Unit, NHS Trust, Great Ormond Street, London WC1N 3JH, UK.
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Johansson M, Jansson L, Ehinger M, Fasth A, Karlsson S, Richter J. Neonatal hematopoietic stem cell transplantation cures oc/oc mice from osteopetrosis. Exp Hematol 2006; 34:242-9. [PMID: 16459192 DOI: 10.1016/j.exphem.2005.11.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 11/10/2005] [Accepted: 11/15/2005] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Infantile malignant osteopetrosis (IMO) is a rare autosomal recessive disorder affecting osteoclast function. Fifty percent of the patients have a mutation in the TCIRG1 gene coding for one subunit of an osteoclast proton pump. The only curative treatment is hematopoietic stem cell transplantation (SCT). The oc/oc mouse has a mutation in the gene homologous to TCIRG1 and its expected lifespan is only 3 to 4 weeks. Previous attempts to cure these mice with SCT have been unsuccessful. We wanted to determine if early hematopoietic SCT using enriched and MHC-matched stem cells can cure oc/oc mice from osteopetrosis. METHODS One- and 8-day-old oc/oc and control mice were radiated with 200, 400, or 600 cGy and transplanted intraperitoneally with 1 or 5 x 10(6) normal lineage-depleted bone marrow cells. Blood, x-ray, and pathology analyses were performed on transplanted mice. RESULTS All 1-day-old mice irradiated with 400 cGy and transplanted with 5 x 10(6) cells survived long term. An engraftment level of 20% is sufficient to correct most features of the disease. X-ray and histopathology examination of transplanted animals showed normalization of bone structure. However, although a correction of bone structure occurred, the transplanted oc/oc mice were smaller in size than their littermates. In contrast to untreated animals, oc/oc mice developed teeth after transplantation, but with abnormal structure and shape making them unusable. CONCLUSION We have shown that this murine form of IMO is curable with neonatal SCT using enriched stem cells.
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Affiliation(s)
- Maria Johansson
- Molecular Medicine and Gene Therapy, Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, University Hospital of Lund, Lund, Sweden
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Vogler C, Levy B, Galvin N, Lessard M, Soper B, Barker J. Early onset of lysosomal storage disease in a murine model of mucopolysaccharidosis type VII: undegraded substrate accumulates in many tissues in the fetus and very young MPS VII mouse. Pediatr Dev Pathol 2005; 8:453-62. [PMID: 16222480 DOI: 10.1007/s10024-005-0025-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Accepted: 05/12/2005] [Indexed: 02/03/2023]
Abstract
Lysosomal storage diseases (LSDs), due to deficiency of a lysosomal enzyme, are inherited, progressive disorders that are often fatal during childhood. The mucopolysaccharidoses (MPS) are LSDs caused by deficiency of a lysosomal enzyme needed for the stepwise degradation of glycosaminoglycans. A murine model of MPS VII shares many clinical, biochemical, and pathologic features with human MPS and has proved valuable for the study of the pathophysiology of MPS and for evaluation of therapies for LSDs. Early therapy of MPS VII mice, initiated in the first weeks of life, is much more effective in decreasing clinical and morphologic evidence of disease than treatment begun in mature animals. Whether such early therapy decreases existing storage or prevents its accumulation is incompletely investigated. We performed an analysis of storage in very young MPS VII mice to define the extent of disease at and before the time of initiation of early treatments. MPS VII pups from 12 days postcoitus (dpc) to 31 days postnatal (dpn) were studied. Storage accumulated in fixed tissue macrophages in the liver and cartilage as soon as 12 dpc and was present in central nervous system glia, leptomeninges, and perivascular cells by 15 dpc. Osteoblast and primitive neocortical cell storage was apparent at 18 to 19 dpc. At 2 dpn, lysosomal distention appeared in circulating leukocytes. Abundant lysosomal storage was present in many sites by 14 dpn. Secondary accumulation of beta-hexosaminidase paralleled increasing glycosaminoglycan storage. These results confirm the presence of widespread storage even in utero and in the very young MPS VII mouse and highlight the importance of early treatment to prevent storage accumulation.
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Affiliation(s)
- Carole Vogler
- Department of Pathology, Saint Louis University School of Medicine, Missouri, 63104, USA.
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