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Evaluation of Gait Pattern and Lower Extremity Kinematics of Children with Morquio Syndrome (MPS IV). Diagnostics (Basel) 2021; 11:diagnostics11081350. [PMID: 34441285 PMCID: PMC8394369 DOI: 10.3390/diagnostics11081350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/22/2021] [Accepted: 07/24/2021] [Indexed: 11/20/2022] Open
Abstract
Morquio syndrome (mucopolysaccharidosis IV/MPS IV) is a genetic disorder leading to skeletal abnormalities and gait deviations. Research on the gait patterns and lower extremity physical characteristics associated with skeletal dysplasia in children with MPS IV is currently limited. This research aimed to provide baseline gait patterns and lower limb skeletal alignment of children with MPS IV utilizing three-dimensional instrumented gait analysis. This Institutional Review Board-approved retrospective study evaluates the kinematics of the lower extremities of children with MPS IV during gait, comparing them with an age-matched group of typically developing children. Thirty-three children with MPS IV were included (8.6 ± 4.0 years old). Children with MPS IV walk with increased anterior pelvic tilt, knee valgus, knee flexion, external tibial torsion, and reduced walking speed and stride length (p < 0.001). Multiplanar abnormal alignment results in abnormal knee moments (p < 0.001). Limited correlations exist (r = 0.69–0.28) between dynamic three-dimensional measurements of knee varus/valgus and rotational alignment and traditional static two-dimensional measures (physical examination or radiographs) suggesting the possibility of knee instability during gait and the benefits of dynamic assessment.
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2
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Evaluation of HIV-1 derived lentiviral vectors as transductors of Mucopolysaccharidosis type IV a fibroblasts. Gene 2021; 780:145527. [PMID: 33636292 DOI: 10.1016/j.gene.2021.145527] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 01/15/2021] [Accepted: 02/09/2021] [Indexed: 11/23/2022]
Abstract
Mucopolysaccharidosis type IVA (MPS IVA) is a lysosomal storage disease produced by the deficiency of the N-acetylgalactosamine-6-sulfate sulfatase (GALNS) enzyme, leading to glycosaminoglycans (GAGs) accumulation. Since currently available treatments remain limited and unspecific, novel therapeutic approaches are essential for the disease treatment. In an attempt to reduce treatment limitations, gene therapy rises as a more effective and specific alternative. We present in this study the delivery assessment of GALNS and sulfatase-modifying factor 1 (SUMF1) genes via HIV-1 derived lentiviral vectors into fibroblasts from MPS IVA patients. After transduction, we determined GALNS enzymatic activity, lysosomal mass change, and autophagy pathway impairment. Additionally, we computationally assessed the effect of mutations over the enzyme-substrate interaction and phenotypic effects. The results showed that the co-transduction of MPS IVA fibroblasts with GALNS and SUMF1 cDNAs led to a significant increase in GALNS enzyme activity and a reduction of lysosomal mass. We show that patient-specific differences in cellular response are directly associated with the set of mutations on each patient. Lastly, we present new evidence supporting autophagy impairment in MPS IVA due to the presence and changes in autophagy proteins in treated MPS IVA fibroblasts. Our results offer new evidence that demonstrate the potential of lentiviral vectors as a strategy to correct GALNS deficiency.
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Broomfield AA, Padidela R, Wilkinson S. Pulmonary Manifestations of Endocrine and Metabolic Diseases in Children. Pediatr Clin North Am 2021; 68:81-102. [PMID: 33228944 DOI: 10.1016/j.pcl.2020.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Advances in technology, methodology, and deep phenotyping are increasingly driving the understanding of the pathologic basis of disease. Improvements in patient identification and treatment are impacting survival. This is true in endocrinology and inborn errors of metabolism, where disease-modifying therapies are developing. Inherent to this evolution is the increasing awareness of the respiratory manifestations of these rare diseases. This review updates clinicians, stratifying diseases spirometerically; pulmonary hypertension and diseases with a predisposition to recurrent pulmonary infection are discussed. This division is artificial; many diseases have multiple pathologic effects on respiration. This review does not cover the impact of obesity.
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Affiliation(s)
- Alexander A Broomfield
- Willink Biochemical Genetics Unit, Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK.
| | - Raja Padidela
- Department of Paediatric Endocrinology, Royal Manchester Children's Hospital, Manchester, UK; Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Stuart Wilkinson
- Respiratory Department Royal Manchester Children's Hospital, Manchester University, NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
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Jiang Z, Byers S, Casal ML, Smith LJ. Failures of Endochondral Ossification in the Mucopolysaccharidoses. Curr Osteoporos Rep 2020; 18:759-773. [PMID: 33064251 PMCID: PMC7736118 DOI: 10.1007/s11914-020-00626-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/29/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW The mucopolysaccharidoses (MPS) are a group of inherited lysosomal storage disorders characterized by abnormal accumulation of glycosaminoglycans (GAGs) in cells and tissues. MPS patients frequently exhibit failures of endochondral ossification during postnatal growth leading to skeletal deformity and short stature. In this review, we outline the current understanding of the cellular and molecular mechanisms underlying failures of endochondral ossification in MPS and discuss associated treatment challenges and opportunities. RECENT FINDINGS Studies in MPS patients and animal models have demonstrated that skeletal cells and tissues exhibit significantly elevated GAG storage from early in postnatal life and that this is associated with impaired cartilage-to-bone conversion in primary and secondary ossification centers, and growth plate dysfunction. Recent studies have begun to elucidate the underlying cellular and molecular mechanisms, including impaired chondrocyte proliferation and hypertrophy, diminished growth factor signaling, disrupted cell cycle progression, impaired autophagy, and increased cell stress and apoptosis. Current treatments such as hematopoietic stem cell transplantation and enzyme replacement therapy fail to normalize endochondral ossification in MPS. Emerging treatments including gene therapy and small molecule-based approaches hold significant promise in this regard. Failures of endochondral ossification contribute to skeletal deformity and short stature in MPS patients, increasing mortality and reducing quality of life. Early intervention is crucial for effective treatment, and there is a critical need for new approaches that normalize endochondral ossification by directly targeting affected cells and signaling pathways.
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Affiliation(s)
- Zhirui Jiang
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, 371 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA, 19104, USA
| | - Sharon Byers
- Genetics and Molecular Pathology, SA Pathology, Adelaide, SA, Australia
- Paediatrics, The University of Adelaide, Adelaide, SA, Australia
- Genetics and Evolution, The University of Adelaide, Adelaide, SA, Australia
| | - Margret L Casal
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Lachlan J Smith
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, 371 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA, 19104, USA.
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Rintz E, Pierzynowska K, Podlacha M, Węgrzyn G. Has resveratrol a potential for mucopolysaccharidosis treatment? Eur J Pharmacol 2020; 888:173534. [PMID: 32877657 DOI: 10.1016/j.ejphar.2020.173534] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/18/2022]
Abstract
Mucopolysaccharidoses (MPS) represent a devastating group of lysosomal storage diseases (LSD) affecting approximately 1 in 25,000 individuals, where degradation of glycosaminoglycans (GAG) by lysosomal enzymes is impaired due to mutations causing defects in one of GAG-degrading enzymes. The most commonly used therapy for MPS is enzyme replacement therapy, consisting of application of an active form of the missing enzyme. However, supply of the missing enzyme is not enough in case of MPS types whose symptoms are expressed in central nervous system (CNS), as enzyme does not cross the blood-brain barrier. Moreover, even though enzyme replacement therapy for non-neuronopathic MPS IVA type is approved, it has a limited impact on bone abnormalities, that are one of main symptoms in the disease. Therefore, research into alternative therapeutic approaches for these types of MPS is highly desirable. One such alternative strategy is accelerated degradation of GAG by induction of autophagy. Autophagy is a process of lysosomal degradation of macromolecules that become abnormal or unnecessary for cells. One of the latest discoveries is that GAGs can also be such molecules. Potential drug should also cross blood-brain barrier and be safe in long-term therapy. It seems that one of the polyphenols, resveratrol, can meet the requirements. The mechanism of its action in autophagy stimulation is pleiotropic. Therefore, in this review, we will briefly discuss potential of resveratrol treatment for mucopolysaccharidosis through autophagy stimulation based on research in diseases with similar outcome.
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Affiliation(s)
- Estera Rintz
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza, 59, 80-308, Gdansk, Poland
| | - Karolina Pierzynowska
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza, 59, 80-308, Gdansk, Poland
| | - Magdalena Podlacha
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza, 59, 80-308, Gdansk, Poland
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza, 59, 80-308, Gdansk, Poland.
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6
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Pediatric Dental Management of an Uncommon Case of Mucopolysaccharidosis Type IV A (Morquio A Syndrome): A Case Report of a Three-Year Follow-Up. Case Rep Dent 2020; 2020:2565486. [PMID: 32411487 PMCID: PMC7204358 DOI: 10.1155/2020/2565486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/31/2019] [Accepted: 11/07/2019] [Indexed: 11/17/2022] Open
Abstract
Mucopolysaccharidosis type IV A or Morquio syndrome is an uncommon inherited metabolic condition caused by the deficient intralysosomal storage of glycosaminoglycans. Diagnosis is typically based on clinical examination, skeletal radiographs, and histochemical tests in blood cells or fibroblasts. It is characterized by evident skeletal deformities, poor joint mobility, severe growth deficit, occlusal anomalies, and enamel defects. The aim of the present clinical case report is to describe the general oral management provided to a 6-year-old female patient and its corresponding evolution for more than three years.
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Różdżyńska-Świątkowska A, Szklanny K, Marucha J, Tylki-Szymańska A. Modeling Morquio A Syndrome: An Anthropometric Study of Body Characteristics and Stature. Diagnostics (Basel) 2020; 10:E116. [PMID: 32093402 PMCID: PMC7168320 DOI: 10.3390/diagnostics10020116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 02/20/2020] [Accepted: 02/20/2020] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Morquio A syndrome or mucopolysaccharidosis (MPS) IVA is an autosomal recessive, life-limiting lysosomal storage disease caused by deficient activity of the enzyme galactosamine-6-sulfatase. Common early symptoms such as abnormalities of body stature can facilitate timely diagnosis. This study aimed to create a pattern of face and body stature based on anthropometric measurements taken from a cohort of Polish patients with MPS IVA. METHODS Analysis of 11 somatometric and 14 craniofacial features was performed on 20 patients with MPS IVA, aged from 3 months to 26 years. The diagnosis of MPS IVA was confirmed by enzymatic and molecular analysis. Two-tailed t-tests were used to compare mean values for body length and weight at birth between the MPS IVA patients and the general population. To show the degree and direction of deviation z-scores were calculated and then used to construct a model of an average MPS IVA patient. RESULTS Mean values for body height and weight at birth were greater for boys than for the general population. The observed pattern of head and body shape indicated that dwarfism occurred with age as a result of the relatively short trunk and lower limbs. Skeletal abnormalities included a bell-shaped chest with the ratio of chest depth to chest width being significantly above the norm. The head and neck were relatively elongated, in comparison to body height, and tucked between narrow shoulders. The head had dolichocephalic shape, while the nose was short with wide nostrils. CONCLUSIONS Multiple anthropometric measurements, including age ranges, allowed for the creation of a model that showed the most characteristic features of the MPS IVA phenotype.
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Affiliation(s)
| | - Krzysztof Szklanny
- Multimedia Department, Polish-Japanese Academy of Information Technology, 02-008 Warsaw, Poland;
| | - Jolanta Marucha
- Department of Paediatrics, Nutrition and Metabolic Diseases, Children’s Memorial Health Institute, 04-730 Warsaw, Poland; (J.M.); (A.T.-S.)
| | - Anna Tylki-Szymańska
- Department of Paediatrics, Nutrition and Metabolic Diseases, Children’s Memorial Health Institute, 04-730 Warsaw, Poland; (J.M.); (A.T.-S.)
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Chien YH, Lee NC, Chen PW, Yeh HY, Gelb MH, Chiu PC, Chu SY, Lee CH, Lee AR, Hwu WL. Newborn screening for Morquio disease and other lysosomal storage diseases: results from the 8-plex assay for 70,000 newborns. Orphanet J Rare Dis 2020; 15:38. [PMID: 32014045 PMCID: PMC6998831 DOI: 10.1186/s13023-020-1322-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/28/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The necessity of early treatment for lysosomal storage diseases (LSDs) has triggered the development of newborn screening for LSDs in recent years. Here we report the first 70,000 newborns screened for Mucopolysaccharidosis (MPS) type 4A (Morquio syndrome) and other LSDs by an 8-plex assay including the original 4-plex LSD screening tandem mass spectrometry (MS/MS) assay for Pompe disease, Fabry disease, Gaucher disease, and MPS I disease. METHODS The additional reaction for MPS II, MPS 3B, MPS 4A, and MPS 6 enzymes was performed separately from the 4-plex reaction. The two reactions were quenched and extracted, then combined before carrying out a single 2-min UPLC-MS/MS analysis. RESULTS From Mar. 2018 to Apr. 2019, 73,743 newborns were screened with the 8-plex LSD screening assay. The 8-plex assay revealed a better analytical precision than the previous 4-plex assay possibly because the 8-plex was carried out using UPLC-MS/MS. Six newborns were found to have low MPS-4A enzyme (N-acetylgalactosamine-6-sulfatase) activity and biallelic GALNS pathogenic mutations in trans; these patients are presumably affected with MPS4A, making an incidence of one in 12,291 (95% confident interval (CI): 5633-26,817). One mutation, c.857C > T (p.T286 M) of the GALNS gene, accounted 5 of the 12 mutated alleles. These newborns had immature vertebral bodies at 1 month of age, and one case was treated with elosulfase alfa 2 mg/kg/week starting from 4 months of age. Among other MPSs screened, one case of MPS I, 3 cases of MPS II, and 3 cases of MPS 3B were detected. One case of mucolipidosis type III was also diagnosed. In conjunction with another 9 patients of Pompe disease, Gaucher disease, and classical Fabry disease, making an incidence of LSDs as one in 3206 newborns (95% CI: 2137 - 4811). The one with infantile-onset Pompe disease and the one with Gaucher disease were treated since the age of 8 days and 41 days respectively. CONCLUSIONS Routine newborn screening of MPS 4A and other LSDs were made possible by the 8-plex LSD screening assay. However, detailed phenotype prediction and the time to start treatment will need further elucidation.
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Affiliation(s)
- Yin-Hsiu Chien
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
- Department of Pediatrics, National Taiwan University Hospital, and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Ni-Chung Lee
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
- Department of Pediatrics, National Taiwan University Hospital, and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Pin-Wen Chen
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Hui-Ying Yeh
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Michael H Gelb
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Pao-Chin Chiu
- Department of Pediatrics, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Shao-Yin Chu
- Department of Pediatrics, Buddhist Tzu-Chi General Hospital, Hualien, Taiwan
| | - Chen-Hao Lee
- Department of Pediatrics, E-DA Hospital, Kaohsiung City, Taiwan
| | - An-Ru Lee
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Wuh-Liang Hwu
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan.
- Department of Pediatrics, National Taiwan University Hospital, and National Taiwan University College of Medicine, Taipei, Taiwan.
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9
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Lin HY, Lo YT, Wang TJ, Huang SF, Tu RY, Chen TL, Lin SP, Chuang CK. Normalization of glycosaminoglycan-derived disaccharides detected by tandem mass spectrometry assay for the diagnosis of mucopolysaccharidosis. Sci Rep 2019; 9:10755. [PMID: 31341247 PMCID: PMC6656773 DOI: 10.1038/s41598-019-46829-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 07/05/2019] [Indexed: 12/22/2022] Open
Abstract
Mucopolysaccharidosis (MPS) is caused by the deficiency of a specific hydrolytic enzyme that catalyzes the step-wise degradation of glycosaminoglycans (GAGs). In this study, we propose an empirical method to calculate levels of GAG-derived disaccharides based on the quantity (peak areas) of chondroitin sulfate (CS) with the aim of making a diagnosis of MPS more accurate and reducing the occurrence of false positive and false negative results. In this study, levels of urinary GAG-derived disaccharides were measured in 67 patients with different types of MPS and 165 controls without MPS using a tandem mass spectrometry assay. Two different methods of reporting GAG-derived disaccharides were assessed; normalization to urinary CS (in μg/mL), and normalization to μg/mg creatinine. CS-normalization yielded more consistent values than creatinine-normalization. In particular, levels of urinary dermatan sulfate (DS), heparan sulfate (HS), and keratan sulfate (KS) significantly varied because of changes in urine creatinine levels, which were proportional to age but inversely proportional to DS, HS, and KS measurements. Using CS-normalization revealed the actual status of DS, HS, and KS without the influence of factors such as age, urine creatinine, and other physiological conditions. It could discriminate between the patients with MPS and controls without MPS, and also to evaluate changes in GAG levels pre- and post-enzyme replacement therapy.
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Affiliation(s)
- Hsiang-Yu Lin
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan.,Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan.,Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan.,Department of Medicine, Mackay Medical College, New Taipei City, Taiwan.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Yun-Ting Lo
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Tuan-Jen Wang
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Sung-Fa Huang
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Ru-Yi Tu
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Tzu-Lin Chen
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Shuan-Pei Lin
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan. .,Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan. .,Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan. .,Department of Medicine, Mackay Medical College, New Taipei City, Taiwan. .,Department of Infant and Child Care, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan.
| | - Chih-Kuang Chuang
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan. .,College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan.
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10
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Xie J, Pan J, Guo D, Pan W, Li R, Guo C, Du M, Jiang W, Guo Y. Mutation analysis and pathogenicity identification of Mucopolysaccharidosis type IVA in 8 south China families. Gene 2018; 686:261-269. [PMID: 30458289 DOI: 10.1016/j.gene.2018.11.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 11/16/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Mucopolysaccharidosis type IVA (MPS IVA) is a rare autosomal recessive lysosomal storage disorder caused by GALNS gene mutation. The aim of our study is to detect pathogenic variants for patients suspected of MPS IVA and set the base for subsequent prenatal diagnosis and preimplantation genetic diagnosis. METHODS In our study, 9 MPS IVA patients from south China families were investigated. Urine glycosaminoglycans (GAGS) screening was used as an initial method. For patients with abnormal result, all 14 exons and intron-exon junctions of the GALNS gene were sequenced after amplification from genomic DNA. The pathogenicity of novel mutations were analyzed with molecular genetics, bioinformatics and structure modeling in light of clinical manifestations and biochemical results. RESULTS Among 12 mutations detected, direct sequencing found 3 novel mutations (c.686A>C, p.Y229S; c.1498G>T, p.G500C; c.278T>C, p.I93T). The pathogenicity of these novel mutations was illustrated by correlating clinical symptoms with pedigree analysis and bioinformatics analysis. CONCLUSION The detection and variant analysis are essential for accurate diagnosis of MPS IVA patients. Our results enrich GALNS gene mutation spectrum of Chinese population. This information has important clinical value for molecular diagnosis and genetic counseling of patients with this disease.
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Affiliation(s)
- Jie Xie
- Department of Medical Genetics, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Jingxin Pan
- Department of Internal Medicine, The Second Affiliated Hospital, Fujian Medical University, Quanzhou 362000, China
| | - Dongwei Guo
- Clinical Medicine, Grade 2014, Medical College, Xiamen University, Xiamen 361102, China
| | - Weimian Pan
- Department of Internal Medicine, The Second Affiliated Hospital, Fujian Medical University, Quanzhou 362000, China
| | - Rong Li
- Department of Medical Genetics, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Chunmiao Guo
- Department of Internal Medicine, The Second Affiliated Hospital, Fujian Medical University, Quanzhou 362000, China
| | - Minlian Du
- Department of Pediatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510620, China
| | - Weiying Jiang
- Department of Medical Genetics, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Yibin Guo
- Department of Medical Genetics, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.
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Chuang CK, Lin HY, Wang TJ, Huang YH, Chan MJ, Liao HC, Lo YT, Wang LY, Tu RY, Fang YY, Chen TL, Ho HC, Chiang CC, Lin SP. Status of newborn screening and follow up investigations for Mucopolysaccharidoses I and II in Taiwan. Orphanet J Rare Dis 2018; 13:84. [PMID: 29801497 PMCID: PMC5970538 DOI: 10.1186/s13023-018-0816-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/26/2018] [Indexed: 11/24/2022] Open
Abstract
Background Mucopolysaccharidoses (MPS) are lysosomal storage diseases in which mutations of genes encoding for lysosomal enzymes cause defects in the degradation of glycosaminoglycans (GAGs). The accumulation of GAGs in lysosomes results in cellular dysfunction and clinical abnormalities. The early initiation of enzyme replacement therapy (ERT) can slow or prevent the development of severe clinical manifestations. MPS I and II newborn screening has been available in Taiwan since August 2015. Infants who failed the recheck at recall were referred to MacKay Memorial Hospital for a detailed confirmatory diagnosis. Methods From August 2015 to November 2017, 294,196 and 153,032 infants were screened using tandem mass spectrometry for MPS I and MPS II, respectively. Of these infants, 84 suspected cases (eight for MPS I; 76 for MPS II) were referred for confirmation. Urinary first-line biochemistry examinations were performed first, including urinary GAG quantification, two-dimensional electrophoresis, and tandem mass spectrometry assay for predominant disaccharides derived from GAGs. If the results were positive, a confirmative diagnosis was made according to the results of leukocyte enzymatic assay and molecular DNA analysis. Leukocyte pellets were isolated from EDTA blood and used for fluorescent α-iduronidase (IDUA) or iduronate-2-sulfatase (IDS) enzymatic assay. DNA sequencing analysis was also performed. Results Normal IDS and IDUA enzyme activities were found in most of the referred cases except for four who were strongly suspected of having MPS I and three who were strongly suspected of having MPS II. Of these infants, three with novel mutations of the IDS gene (c.817C > T, c.1025A > G, and c.311A > T) and four with two missense mutations of the IDUA gene (C.300-3C > G, c.1874A > C; c.1037 T > G, c.1091C > T) showed significant deficiencies in IDS and IDUA enzyme activities (< 5% of mean normal activity), respectively. Urinary dermatan sulfate and heparan sulfate quantitative analyses by tandem mass spectrometry also demonstrated significant elevations. The prevalence rates of MPS I and MPS II in Taiwan were 1.35 and 1.96 per 100,000 live births, respectively. Conclusions The early initiation of ERT for MPS can result in better clinical outcomes. An early confirmatory diagnosis increases the probability of receiving appropriate medical care such as ERT quickly enough to avoid irreversible manifestations. All high risk infants identified in this study so far remain asymptomatic and are presumed to be affected with the attenuated disease variants.
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Affiliation(s)
- Chih-Kuang Chuang
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan.,College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan
| | - Hsiang-Yu Lin
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan.,Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan.,The Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan.,Department of Early Childhood Care and Education, Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan.,Department of Medicine, MacKay Medical College, Taipei, Taiwan.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Tuan-Jen Wang
- Department of Laboratory Medicine, MacKay Memorial Hospital, Taipei, Taiwan
| | - You-Hsin Huang
- The Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
| | - Min-Ju Chan
- The Chinese Foundation of Health, Neonatal Screening Center, Taipei, Taiwan
| | - Hsuan-Chieh Liao
- The Chinese Foundation of Health, Neonatal Screening Center, Taipei, Taiwan
| | - Yun-Ting Lo
- Department of Laboratory Medicine, MacKay Memorial Hospital, Taipei, Taiwan
| | - Li-Yun Wang
- Taipei Institute of Pathology, Neonatal Screening Center, Taipei, Taiwan
| | - Ru-Yi Tu
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
| | - Yi-Ya Fang
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
| | - Tzu-Lin Chen
- Department of Laboratory Medicine, MacKay Memorial Hospital, Taipei, Taiwan
| | - Hui-Chen Ho
- Taipei Institute of Pathology, Neonatal Screening Center, Taipei, Taiwan
| | - Chuan-Chi Chiang
- The Chinese Foundation of Health, Neonatal Screening Center, Taipei, Taiwan.
| | - Shuan-Pei Lin
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan. .,Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan. .,The Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan. .,Department of Early Childhood Care and Education, Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan. .,Department of Infant and Child Care, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan. .,Departments of Pediatrics and Medical Research, MacKay Memorial Hospital, No. 92, Sec. 2, Chung-Shan N. Rd, Taipei, 10449, Taiwan.
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12
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Chuang CK, Lin HY, Wang TJ, Huang SF, Lin SP. Bio-Plex immunoassay measuring the quantity of lysosomal N-acetylgalactosamine-6-sulfatase protein in dried blood spots for the screening of mucopolysaccharidosis IVA in newborn: a pilot study. BMJ Open 2017; 7:e014410. [PMID: 28710204 PMCID: PMC5734244 DOI: 10.1136/bmjopen-2016-014410] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Mucopolysaccharidosis (MPS) IVA (Morquio syndrome A) is an autosomal-recessive lysosomal storage disorder caused by the deficiency of N-acetylgalactosamine-6-sulfatase (GALNS) resulting in excessive lysosomal storage of keratan sulfate. Treatments for MPS IVA have recently become available with optimal outcomes associated with early diagnosis and treatment which can be achieved by newborn screening. DESIGN Newborn screening programme for MPS IVA pilot study. SETTING MacKay Memorial Hospital (MMH), Taipei and another three branch hospitals in Taiwan. PARTICIPANTS A total of 7415 newborns were born in four branch hospitals of MMH and had joined the MPS IVA newborn screening programme. Written informed consents were obtained from parents prior to the screening process (12MMHIS188 approved by MacKay Memorial Hospital Institutional Review Board). OUTCOME MEASURES An alternative newborn screening method for MPS IVA has been performed. Screening involved measuring the quantity of GALNS in dried blood spot (DBS) from newborn infants using the Bio-Plex immunoassay. The amount of fluorescence sorting detected by yttrium aluminium garnet laser was proportional to the quantity of GALNS protein. RESULTS Of the 7415 neonates analysed, eight infants whose GALNS levels were below the cut-off value of 8.30 µg/L had been recalled for a second DBS collection. The reference values were 8.30-27.43 µg/L. In patients with confirmed MPS IVA (n=11), the GALNS quantities were far below 5% of the normal population. CONCLUSION The Bio-Plex immunoassay is a validated method used for measuring GALNS protein in DBS and has the potential to be adopted for MPS IVA newborn screening study design.
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Affiliation(s)
- Chih-Kuang Chuang
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
- College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan
- Departmentof Chemical Engineering and Biotechnology, Institute of Chemical Engineering. National Taipei University of Technology, Taipei, Taiwan., Taipei, Taiwan
| | - Hsiang-Yu Lin
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
- Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan
- Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan
- Department of Medicine, Mackay Medical College, New Taipei City, Taiwan
| | - Tuan-Jen Wang
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Sung-Fa Huang
- Department of Laboratory Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Shuan-Pei Lin
- Division of Genetics and Metabolism, Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
- Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan
- Department of Medicine, Mackay Medical College, New Taipei City, Taiwan
- Department of Infant and Child Care, National Taipei University of Nursing and Health Science, Taipei, Taiwan
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13
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Jelin AC, O'Hare E, Blakemore K, Jelin EB, Valle D, Hoover-Fong J. Skeletal Dysplasias: Growing Therapy for Growing Bones. Front Pharmacol 2017; 8:79. [PMID: 28321190 PMCID: PMC5337493 DOI: 10.3389/fphar.2017.00079] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 02/07/2017] [Indexed: 12/24/2022] Open
Abstract
Skeletal dysplasias represent a large and diverse group of rare conditions affecting collagen and bone. They can be clinically classified based on radiographic and physical features, and many can be further defined at a molecular level (Bonafe et al., 2015). Early diagnosis is critical to proper medical management including pharmacologic treatment when available. Patients with severe skeletal dysplasias often have small chests with respiratory insufficiency or airway obstruction and require immediate intubation after birth. Thereafter a variety of orthopedic, neurosurgical, pulmonary, otolaryngology interventions may be needed. In terms of definitive treatment for skeletal dysplasias, there are few pharmacotherapeutic options available for the majority of these conditions. We sought to describe therapies that are currently available or under investigation for skeletal dysplasias.
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Affiliation(s)
- Angie C. Jelin
- Gynecology and Obstetrics, Johns Hopkins University School of MedicineBaltimore, MD, USA
| | | | - Karin Blakemore
- Gynecology and Obstetrics, Johns Hopkins University School of MedicineBaltimore, MD, USA
| | - Eric B. Jelin
- Pediatric Surgery, Johns Hopkins University School of MedicineBaltimore, MD, USA
| | - David Valle
- Genetics, Johns Hopkins University School of MedicineBaltimore, MD, USA
| | - Julie Hoover-Fong
- Genetics, Johns Hopkins University School of MedicineBaltimore, MD, USA
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14
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Khan S, Alméciga-Díaz CJ, Sawamoto K, Mackenzie WG, Theroux MC, Pizarro C, Mason RW, Orii T, Tomatsu S. Mucopolysaccharidosis IVA and glycosaminoglycans. Mol Genet Metab 2017; 120:78-95. [PMID: 27979613 PMCID: PMC5293636 DOI: 10.1016/j.ymgme.2016.11.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 12/21/2022]
Abstract
Mucopolysaccharidosis IVA (MPS IVA; Morquio A: OMIM 253000) is a lysosomal storage disease with an autosomal recessive trait caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase. Deficiency of this enzyme leads to accumulation of specific glycosaminoglycans (GAGs): chondroitin-6-sulfate (C6S) and keratan sulfate (KS). C6S and KS are mainly produced in the cartilage. Therefore, the undegraded substrates are stored primarily in cartilage and in its extracellular matrix (ECM), leading to a direct impact on cartilage and bone development, and successive systemic skeletal dysplasia. Chondrogenesis, the earliest phase of skeletal formation, is maintained by cellular interactions with the ECM, growth and differentiation factors, signaling pathways, and transcription factors in a temporal-spatial manner. In patients with MPS IVA, the cartilage is disrupted at birth as a consequence of abnormal chondrogenesis and/or endochondral ossification. The unique skeletal features are distinguished by a disproportional short stature, odontoid hypoplasia, spinal cord compression, tracheal obstruction, pectus carinatum, kyphoscoliosis, platyspondyly, coxa valga, genu valgum, waddling gait, and laxity of joints. In spite of many descriptions of these unique clinical features, delay of diagnosis still happens. The pathogenesis and treatment of systemic skeletal dysplasia in MPS IVA remains an unmet challenge. In this review article, we comprehensively describe historical aspect, property of GAGs, diagnosis, screening, pathogenesis, and current and future therapies of MPS IVA.
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Affiliation(s)
- Shaukat Khan
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Carlos J Alméciga-Díaz
- Institute for the Study of Inborn Errors of Metabolism, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - Kazuki Sawamoto
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - William G Mackenzie
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Mary C Theroux
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Christian Pizarro
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Robert W Mason
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States; Department of Pediatrics, Gifu University, Gifu, Japan; Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA, United States.
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15
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Yap P, Savarirayan R. Emerging targeted drug therapies in skeletal dysplasias. Am J Med Genet A 2016; 170:2596-604. [PMID: 27155200 DOI: 10.1002/ajmg.a.37734] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/28/2016] [Indexed: 11/10/2022]
Abstract
Quantum advances have occurred in the field of human genetics in the six decades since Watson and Crick expressed their "wish to suggest a structure for the salt of deoxyribose nucleic acid." These culminated with the human genome project, which has opened up myriad possibilities, including that of individualized genetic medicine, the ability to deliver medical advice, management, and therapy tailored to an individual's genetic blueprint. Advances in genetic diagnostic capabilities have been rapid, to the point where the genome can be sequenced for several thousand dollars. Crucially, it has facilitated the identification of targets for "precision" treatments to combat genetic diseases at their source. This manuscript will review the innovative, pathogenesis-based therapies that are revolutionizing management of skeletal dysplasias, giving patients and families new options and outcomes. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Patrick Yap
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia
| | - Ravi Savarirayan
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia. .,Department of Pediatrics, University of Melbourne, Melbourne, Australia.
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16
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Yabe H, Tanaka A, Chinen Y, Kato S, Sawamoto K, Yasuda E, Shintaku H, Suzuki Y, Orii T, Tomatsu S. Hematopoietic stem cell transplantation for Morquio A syndrome. Mol Genet Metab 2016; 117:84-94. [PMID: 26452513 PMCID: PMC5016080 DOI: 10.1016/j.ymgme.2015.09.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 12/15/2022]
Abstract
Morquio A syndrome features systemic skeletal dysplasia. To date, there has been no curative therapy for this skeletal dysplasia. No systemic report on a long-term effect of hematopoietic stem cell transplantation (HSCT) for Morquio A has been described. We conducted HSCT for 4 cases with Morquio A (age at HSCT: 4-15years, mean 10.5years) and followed them at least 10years (range 11-28years; mean 19years). Current age ranged between 25 and 36years of age (mean 29.5years). All cases had a successful full engraftment of allogeneic bone marrow transplantation without serious GVHD. Transplanted bone marrow derived from HLA-identical siblings (three cases) or HLA-identical unrelated donor. The levels of the enzyme activity in the recipient's lymphocytes reached the levels of donors' enzyme activities within two years after HSCT. For the successive over 10years post-BMT, GALNS activity in lymphocytes was maintained at the same level as the donors. Except one case who had osteotomy in both legs one year later post BMT, other three cases had no orthopedic surgical intervention. All cases remained ambulatory, and three of them could walk over 400m. Activity of daily living (ADL) in patients with HSCT was better than untreated patients. The patient who underwent HSCT at four years of age showed the best ADL score. In conclusion, the long-term study of HSCT has demonstrated therapeutic effect in amelioration of progression of the disease in respiratory function, ADL, and biochemical findings, suggesting that HSCT is a therapeutic option for patients with Morquio A.
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Affiliation(s)
- Hiromasa Yabe
- Department of Cell Transplantation and Regenerative Medicine, Tokai University School of Medicine, Isehara, Japan.
| | - Akemi Tanaka
- Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
| | - Yasutsugu Chinen
- Department of Pediatrics, Faculty of Medicine, University of the Ryukyus, Japan.
| | - Shunichi Kato
- Department of Cell Transplantation and Regenerative Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Kazuki Sawamoto
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Eriko Yasuda
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States
| | - Haruo Shintaku
- Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Yasuyuki Suzuki
- Medical Education Development Center, Gifu University, Japan
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan
| | - Shunji Tomatsu
- Department of Pediatrics, Gifu University, Gifu, Japan; Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, United States.
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17
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Giugliani R, Federhen A, Vairo F, Vanzella C, Pasqualim G, da Silva LMR, Giugliani L, de Boer APK, de Souza CFM, Matte U, Baldo G. Emerging drugs for the treatment of mucopolysaccharidoses. Expert Opin Emerg Drugs 2016; 21:9-26. [PMID: 26751109 DOI: 10.1517/14728214.2016.1123690] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION Despite being reported for the first time almost one century ago, only in the last few decades effective have treatments become available for the mucopolysaccharidoses (MPSs), a group of 11 inherited metabolic diseases that affect lysosomal function. These diseases are progressive, usually severe, and, in a significant number of cases, involve cognitive impairment. AREAS COVERED This review will not cover established treatments such as bone marrow/hematopoietic stem cell transplantation and classic intravenous enzyme replacement therapy (ERT), whose long-term outcomes have already been published (MPS I, MPS II, and MPS VI), but it instead focuses on emerging therapies for MPSs. That includes intravenous ERT for MPS IVA and VII, intrathecal ERT, ERT with fusion proteins, substrate reduction therapy, gene therapy, and other novel approaches. EXPERT OPINION The available treatments have resulted in improvements for several disease manifestations, but they still do not represent a cure for these diseases; thus, it is important to develop alternative methods to approach the unmet needs (i.e. bone disease, heart valve disease, corneal opacity, and central nervous system (CNS) involvement). The work in progress with novel approaches makes us confident that in 2017, when MPS will commemorate 100 years of its first report, we will be much closer to an effective cure for these challenging conditions.
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Affiliation(s)
- Roberto Giugliani
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil.,b Department of Genetics , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.,c Post-Graduate Program in Child and Adolescent Health , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.,d Post-Graduate Program in Genetics and Molecular Biology , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Andressa Federhen
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil.,c Post-Graduate Program in Child and Adolescent Health , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Filippo Vairo
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Cláudia Vanzella
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil.,e Post-Graduate Program in Biological Sciences: Biochemistry , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Gabriela Pasqualim
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil.,b Department of Genetics , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Letícia Machado Rosa da Silva
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Luciana Giugliani
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Ana Paula Kurz de Boer
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Carolina Fishinger Moura de Souza
- a Medical Genetics Service and Clinical Research Group in Medical Genetics , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Ursula Matte
- b Department of Genetics , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.,d Post-Graduate Program in Genetics and Molecular Biology , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.,f Gene Therapy Center , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil
| | - Guilherme Baldo
- d Post-Graduate Program in Genetics and Molecular Biology , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil.,f Gene Therapy Center , Hospital de Clínicas de Porto Alegre , Porto Alegre , Brazil.,g Department of Physiology , Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
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18
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Tomatsu S, Sawamoto K, Shimada T, Bober MB, Kubaski F, Yasuda E, Mason RW, Khan S, Alméciga-Díaz CJ, Barrera LA, Mackenzie WG, Orii T. Enzyme replacement therapy for treating mucopolysaccharidosis type IVA (Morquio A syndrome): effect and limitations. Expert Opin Orphan Drugs 2015; 3:1279-1290. [PMID: 26973801 PMCID: PMC4788508 DOI: 10.1517/21678707.2015.1086640] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Following a Phase III, randomized, double-blind, placebo (PBO)-controlled, multinational study in subjects with mucopolysaccharidosis IVA (MPS IVA), enzyme replacement therapy (ERT) of elosulfase alfa has been approved in several countries. The study was designed to evaluate safety and efficacy of elosulfase alfa in patients with MPS IVA aged 5 years and older. AREAS COVERED Outcomes of clinical trials for MPS IVA have been described. Subjects received either 2.0 mg/kg/week, 2.0 mg/kg/every other week, or PBO, for 24 weeks. The primary endpoint was the change from baseline 6-min walk test (6MWT) distance compared to PBO. The 6MWT results improved in patients receiving 2 mg/kg weekly compared to PBO. The every other week regimen resulted in walk distances comparable to PBO. There was no change from baseline in the 3 Min Stair Climb Test in both treatment groups. Following completion of the initial study, patients, who continued to receive elosulfase alfa 2 mg/kg weekly (QW) for another 48 weeks (for a total of up to 72-week exposure), did not show additional improvement on 6MWT. EXPERT OPINION We suggest that ERT is a therapeutic option for MPS IVA, providing a modest effect and the majority of the effects are seen in the soft tissues.
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Affiliation(s)
- Shunji Tomatsu
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
- Department of Pediatrics, Gifu University, Gifu, Japan, Japan
| | - Kazuki Sawamoto
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
| | - Tsutomu Shimada
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
- Department of Medical Informatics, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Michael B. Bober
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
| | - Francyne Kubaski
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Eriko Yasuda
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
- Department of Medical Informatics, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Robert W. Mason
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
| | - Shaukat Khan
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
| | - Carlos J. Alméciga-Díaz
- Institute for the Study of Inborn Errors of Metabolism, School of Sciences, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Luis A. Barrera
- Institute for the Study of Inborn Errors of Metabolism, School of Sciences, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - William G. Mackenzie
- Professor and Director, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd., Wilmington, DE 19899-0269, USA
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan, Japan
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Novel missense mutation in the GALNS gene in an affected patient with severe form of mucopolysaccharidosis type IVA. Clin Chim Acta 2015; 450:121-4. [PMID: 26276046 DOI: 10.1016/j.cca.2015.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 08/09/2015] [Indexed: 11/20/2022]
Abstract
Mucopolysaccharidosis type IVA (MPS IVA), also known as Morquio A, is an autosomal recessive disorder characterized by a deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), which causes major skeletal and connective tissue abnormalities and affects multiple organ systems. In this study, one MPS IVA patient with a severe form from consanguine large Iranian family has been investigated. To find a mutation, all of the 14 exons and intron-exon junctions of GALNS gene were sequenced. Sequencing results were analyzed using bioinformatic analysis in order to predict probable pathogenic effect of the variant. One novel homozygous missense mutation in exon 5, c.542A>G (p.Y181C), was found in the proband. That was predicted as being probably pathogenic by bioinformatics analysis. Segregation and familial study confirmed this pathogenic mutation. In conclusion, we have identified the novel mutation responsible for MPS IVA in an Iranian patient to assist in the diagnosis, genetic counseling and prenatal diagnosis of the affected families.
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20
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Kubaski F, Tomatsu S, Patel P, Shimada T, Xie L, Yasuda E, Mason R, Mackenzie WG, Theroux M, Bober MB, Oldham HM, Orii T, Shaffer TH. Non-invasive pulmonary function test on Morquio patients. Mol Genet Metab 2015; 115:186-92. [PMID: 26116954 PMCID: PMC4706533 DOI: 10.1016/j.ymgme.2015.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 06/19/2015] [Accepted: 06/20/2015] [Indexed: 12/13/2022]
Abstract
In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and/or obstructive lung disease.
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Affiliation(s)
- Francyne Kubaski
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Pediatrics, Gifu University, Gifu, Japan.
| | - Pravin Patel
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Tsutomu Shimada
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Li Xie
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Eriko Yasuda
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Robert Mason
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | | | - Mary Theroux
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Michael B Bober
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Helen M Oldham
- Department of Respiratory Care, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan
| | - Thomas H Shaffer
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Center for Pediatric Lung Research, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA.
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21
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Di-sulfated Keratan Sulfate as a Novel Biomarker for Mucopolysaccharidosis II, IVA, and IVB. JIMD Rep 2015; 21:1-13. [PMID: 25712379 DOI: 10.1007/8904_2014_330] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 05/29/2014] [Accepted: 06/12/2014] [Indexed: 01/07/2023] Open
Abstract
Keratan sulfate (KS) is a storage material in mucopolysaccharidosis IV (MPS IV). However, no detailed analysis has been reported on subclasses of KS: mono-sulfated KS and di-sulfated KS. We established a novel method to distinguish and quantify mono- and di-sulfated KS using liquid chromatography-tandem mass spectrometry and measured both KS levels in various specimens.Di-sulfated KS was dominant in shark cartilage and rat serum, while mono-sulfated KS was dominant in bovine cornea and human serum. Levels of both mono- and di-sulfated KS varied with age in the blood and urine from control subjects and patients with MPS II and IVA. The mean levels of both forms of KS in the plasma/serum from patients with MPS II, IVA, and IVB were elevated compared with that in age-matched controls. Di-sulfated KS provided more significant difference between MPS IVA and the age-matched controls than mono-sulfated KS. The ratio of di-sulfated KS to total KS in plasma/serum increased with age in control subjects and patients with MPS II but was age independent in MPS IVA patients. Consequently, this ratio can discriminate younger MPS IVA patients from controls. Levels of mono- and di-sulfated KS in urine of MPS IVA and IVB patients were all higher than age-matched controls for all ages studied.In conclusion, the level of di-sulfated KS and its ratio to total KS can distinguish control subjects from patients with MPS II, IVA, and IVB, indicating that di-sulfated KS may be a novel biomarker for these disorders.
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Tomatsu S, Montaño AM, Oikawa H, Dung VC, Hashimoto A, Oguma T, Gutiérrez ML, Takahashi T, Shimada T, Orii T, Sly WS. Enzyme replacement therapy in newborn mucopolysaccharidosis IVA mice: early treatment rescues bone lesions? Mol Genet Metab 2015; 114:195-202. [PMID: 24953405 PMCID: PMC4256128 DOI: 10.1016/j.ymgme.2014.05.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 05/27/2014] [Accepted: 05/27/2014] [Indexed: 02/02/2023]
Abstract
We treated mucopolysaccharidosis IVA (MPS IVA) mice to assess the effects of long-term enzyme replacement therapy (ERT) initiated at birth, since adult mice treated by ERT showed little improvement in bone pathology [1]. To conduct ERT in newborn mice, we used recombinant human N-acetylgalactosamine-6-sulfate sulfatase (GALNS) produced in a CHO cell line. First, to observe the tissue distribution pattern, a dose of 250units/g body weight was administered intravenously in MPS IVA mice at day 2 or 3. The infused enzyme was primarily recovered in the liver and spleen, with detectable activity in the bone and brain. Second, newborn ERT was conducted after a tissue distribution study. The first injection of newborn ERT was performed intravenously, the second to fourth weekly injections were intraperitoneal, and the remaining injections from 5th to 14th weeks were intravenous into the tail vein. MPS IVA mice treated with GALNS showed clearance of lysosomal storage in the liver and spleen, and sinus lining cells in bone marrow. The column structure of the growth plate was organized better than that in adult mice treated with ERT; however, hyaline and fibrous cartilage cells in the femur, spine, ligaments, discs, synovium, and periosteum still had storage materials to some extent. Heart valves were refractory to the treatment. Levels of serum keratan sulfate were kept normal in newborn ERT mice. In conclusion, the enzyme, which enters the cartilage before the cartilage cell layer becomes mature, prevents disorganization of column structure. Early treatment from birth leads to partial remission of bone pathology in MPS IVA mice.
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Affiliation(s)
- Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
| | - Adriana M Montaño
- Department of Pediatrics, Saint Louis University Doisy Research Center, St. Louis, MO, USA; Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | - Hirotaka Oikawa
- Suzuka University of Medical Science, School of Pharmacy, Japan
| | - Vu Chi Dung
- Department of Endocrinology, Metabolism & Genetics, Vietnam National Hospital of Pediatrics, Hanoi, Viet Nam
| | | | | | - Monica L Gutiérrez
- Department of Pediatrics, Saint Louis University Doisy Research Center, St. Louis, MO, USA
| | - Tatsuo Takahashi
- Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Hokuriku University, Kanazawa, Japan
| | - Tsutomu Shimada
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Tadao Orii
- Department of Pediatrics, Gifu University, School of Medicine, Gifu, Japan
| | - William S Sly
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA
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Tomatsu S, Alméciga-Díaz CJ, Montaño AM, Yabe H, Tanaka A, Dung VC, Giugliani R, Kubaski F, Mason RW, Yasuda E, Sawamoto K, Mackenzie W, Suzuki Y, Orii KE, Barrera LA, Sly WS, Orii T. Therapies for the bone in mucopolysaccharidoses. Mol Genet Metab 2015; 114:94-109. [PMID: 25537451 PMCID: PMC4312706 DOI: 10.1016/j.ymgme.2014.12.001] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 11/30/2014] [Accepted: 12/01/2014] [Indexed: 12/24/2022]
Abstract
Patients with mucopolysaccharidoses (MPS) have accumulation of glycosaminoglycans in multiple tissues which may cause coarse facial features, mental retardation, recurrent ear and nose infections, inguinal and umbilical hernias, hepatosplenomegaly, and skeletal deformities. Clinical features related to bone lesions may include marked short stature, cervical stenosis, pectus carinatum, small lungs, joint rigidity (but laxity for MPS IV), kyphoscoliosis, lumbar gibbus, and genu valgum. Patients with MPS are often wheelchair-bound and physical handicaps increase with age as a result of progressive skeletal dysplasia, abnormal joint mobility, and osteoarthritis, leading to 1) stenosis of the upper cervical region, 2) restrictive small lung, 3) hip dysplasia, 4) restriction of joint movement, and 5) surgical complications. Patients often need multiple orthopedic procedures including cervical decompression and fusion, carpal tunnel release, hip reconstruction and replacement, and femoral or tibial osteotomy through their lifetime. Current measures to intervene in bone disease progression are not perfect and palliative, and improved therapies are urgently required. Enzyme replacement therapy (ERT), hematopoietic stem cell transplantation (HSCT), and gene therapy are available or in development for some types of MPS. Delivery of sufficient enzyme to bone, especially avascular cartilage, to prevent or ameliorate the devastating skeletal dysplasias remains an unmet challenge. The use of an anti-inflammatory drug is also under clinical study. Therapies should start at a very early stage prior to irreversible bone lesion, and damage since the severity of skeletal dysplasia is associated with level of activity during daily life. This review illustrates a current overview of therapies and their impact for bone lesions in MPS including ERT, HSCT, gene therapy, and anti-inflammatory drugs.
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Affiliation(s)
- Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Medical Genetics Service/HCPA and Department of Genetics/UFRGS, Porto Alegre, Brazil.
| | - Carlos J Alméciga-Díaz
- Institute for the Study of Inborn Errors of Metabolism, Pontificia Universidad Javeriana, Bogotá, D.C., Colombia
| | - Adriana M Montaño
- Department of Pediatrics, Saint Louis University, St. Louis, MO, USA
| | - Hiromasa Yabe
- Department of Cell Transplantation, Tokai University School of Medicine, Isehara, Japan
| | - Akemi Tanaka
- Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Vu Chi Dung
- Department of Endocrinology, Metabolism & Genetics, Vietnam National Hospital of Pediatrics, Hanoi, Viet Nam
| | - Roberto Giugliani
- Medical Genetics Service/HCPA and Department of Genetics/UFRGS, Porto Alegre, Brazil
| | - Francyne Kubaski
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Robert W Mason
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Eriko Yasuda
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Kazuki Sawamoto
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | | | - Yasuyuki Suzuki
- Medical Education Development Center, Gifu University, Japan
| | - Kenji E Orii
- Department of Pediatrics, Gifu University, Gifu, Japan
| | - Luis A Barrera
- Institute for the Study of Inborn Errors of Metabolism, Pontificia Universidad Javeriana, Bogotá, D.C., Colombia
| | - William S Sly
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan.
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Chondroitin 6-Sulfate as a Novel Biomarker for Mucopolysaccharidosis IVA and VII. JIMD Rep 2014; 16:15-24. [PMID: 24850234 DOI: 10.1007/8904_2014_311] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/06/2014] [Accepted: 03/12/2014] [Indexed: 12/02/2022] Open
Abstract
Chondroitin 6-sulfate (C6S), a glycosaminoglycan (GAG), is distributed mainly in the growth plates, aorta, and cornea; however, the physiological function of C6S is not fully understood. One of the limitations is that no rapid, accurate quantitative method to measure C6S has been established. Mucopolysaccharidosis IVA and VII (MPS IVA and VII) are caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase and β-D-glucuronidase, respectively, resulting in accumulation of C6S and other GAG(s). While levels of keratan sulfate (KS), heparan sulfate, and dermatan sulfate in samples from MPS patients are well described, this is the first report of quantitative analysis of C6S levels in samples from MPS IVA and VII patients.We developed a method to digest polymeric C6S and measure resultant disaccharides using liquid chromatography-tandem mass spectrometry (LC-MS/MS). C6S levels were measured in the blood from control subjects and patients with MPS IVA and VII aged from 0 to 58 years of age. We also assayed KS levels in the same samples for comparison with C6S.Levels of C6S in the blood decreased with age and were significantly elevated in patients with MPS IVA and VII, compared with age-matched controls. Levels of KS in patients with MPS IVA were also higher than those in age-matched controls, although differences were less pronounced than with C6S. Combining KS and C6S data, discriminated patients with MPS IVA from age-matched control subjects were better than either C6S or KS levels alone.In conclusion, this first report showing that blood levels of C6S are quantitatively evaluated in patients with MPS IVA and VII indicates that C6S could be a useful biomarker for these metabolic disorders.
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