scholarly journals Recombinant α-l-iduronidase: characterization of the purified enzyme and correction of mucopolysaccharidosis type I fibroblasts

1994 ◽  
Vol 304 (1) ◽  
pp. 43-49 ◽  
Author(s):  
E G Unger ◽  
J Durrant ◽  
D S Anson ◽  
J J Hopwood
Keyword(s):  
Specific Activity ◽  
Heparan Sulphate ◽  
Chinese Hamster ◽  
Reducing Agents ◽  
Chain Elongation ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Enzyme Replacement ◽  
Mps I

Mucopolysaccharidosis type I (MPS I, Hurler and Scheie syndromes) is an autosomal recessive lysosomal storage disorder that results from a deficiency of the hydrolase alpha-L-iduronidase (IDUA) which is involved in the lysosomal degradation of both heparan sulphate (HS) and dermatan sulphate (DS). Patients with MPS I store and excrete large amounts of partially degraded HS and DS. In order to evaluate enzyme replacement therapy for MPS I patients we have expressed human IDUA cDNA in Chinese Hamster Ovary (CHO)-K1 cells utilizing a plasmid vector that places the cDNA under the transcriptional control of the human polypeptide-chain-elongation factor I alpha gene promoter. A clonal cell-line that secreted recombinant IDUA in a precursor form at approximately 2.2 micrograms/10(6) cells per day was identified. This enzyme was shown to be endocytosed into cultured MPS I fibroblasts via mannose-6-phosphate receptors and to correct the storage phenotype of these cells by enabling the lysosomal-digestion of accumulated sulphated glycosaminoglycans. The recombinant IDUA had on SDS/PAGE a molecular mass of 85 kDa and was processed to 74 kDa and smaller forms following its uptake by fibroblasts. Milligram quantities of the recombinant IDUA were immunopurified and the enzyme was shown to have pH optimum and kinetic parameters differing from those of the mature enzyme purified from human liver. The specific activity of the recombinant enzyme was shown to increase on dilution and on incubation with reducing agents. This was in contrast to the mature IDUA form (74 kDa) which did not have its activity stimulated by reducing agents or dilution.

scholarly journals Report of Five Years of Experience in Neonatal Screening for Mucopolysaccharidosis Type I and Review of the Literature

2020 ◽  
Vol 6 (4) ◽  
pp. 85 ◽  
Author(s):  
Vincenza Gragnaniello ◽  
Daniela Gueraldi ◽  
Laura Rubert ◽  
Francesca Manzoni ◽  
Chiara Cazzorla ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Early Treatment ◽  
Molecular Testing ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Years Of Experience ◽  
Enzyme Replacement ◽  
Second Tier ◽  
Mps I

Mucopolysaccharidosis type I (MPS I) is a progressive lysosomal storage disease, with neurological and visceral involvement, in which early diagnosis through newborn screening (NBS) and early treatment can improve outcomes. We present our first 5 years of experience with laboratory and clinical management of NBS for MPS I. Since 2015, we have screened 160,011 newborns by measuring α-L-iduronidase (IDUA) activity and, since 2019, glycosaminoglycans (GAGs) in dried blood spot (DBS) as a second-tier test. Positive screening patients were referred to our clinic for confirmatory clinical and molecular testing. We found two patients affected by MPS I (incidence of 1:80,005). Before the introduction of second-tier testing, we found a high rate of false-positives due to pseudodeficiency. With GAG analysis in DBS as a second-tier test, no false-positive newborns were referred to our clinic. The confirmed patients were early treated with enzyme replacement therapy and bone-marrow transplantation. For both, the clinical outcome of the disease is in the normal range. Our experience confirms that NBS for MPS I is feasible and effective, along with the need to include GAG assay as a second-tier test. Follow-up of the two positive cases identified confirms the importance of early diagnosis through NBS and early treatment to improve the outcome of these patients.

scholarly journals Recombinant human iduronate-2-sulphatase: correction of mucopolysaccharidosis-type II fibroblasts and characterization of the purified enzyme

1993 ◽  
Vol 289 (1) ◽  
pp. 241-246 ◽  
Author(s):  
J Bielicki ◽  
J J Hopwood ◽  
P J Wilson ◽  
D S Anson
Keyword(s):  
Cell Line ◽  
Heparan Sulphate ◽  
Chinese Hamster ◽  
Chain Elongation ◽  
Mucopolysaccharidosis Type ◽  
Type Ii ◽  
Mucopolysaccharidosis Type Ii ◽  
Ph Optimum ◽  
Enzyme Replacement ◽  
Mps Ii

Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is an X-chromosome-linked recessive lysosomal storage disorder that results from a deficiency of iduronate-2-sulphatase (12S). Patients with MPS II store and excrete large amounts of partially degraded heparan sulphate and dermatan sulphate. In order to evaluate enzyme-replacement therapy for MPS II we have expressed a chimaeric I2S cDNA in CHO (Chinese-hamster ovary)-K1 cells utilizing a plasmid vector that places the cDNA under the transcriptional control of the human polypeptide-chain-elongation factor-1 alpha gene promoter. A clonal cell line that accumulated recombinant I2S at greater than 10 mg/ml in conditioned medium was identified. Enzyme secreted from this cell line grown in the presence of NH4Cl was shown to be endocytosed into MPS II fibroblasts via the mannose 6-phosphate receptor and localized to the lysosomal compartment, resulting in correction of the storage phenotype of these cells. Milligram quantities of the recombinant I2S were purified, and the enzyme was shown to have a pH optimum and kinetic parameters similar to those for the mature form of I2S purified from human liver. The recombinant I2S had a molecular mass of approx. 90 kDa; this was reduced to 60 kDa by endoglycosidase treatment.

scholarly journals Macular Changes in a Mucopolysaccharidosis Type I Patient with Earlier Systemic Therapies

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Augusto Magalhães ◽  
Ana Maria Cunha ◽  
Rodrigo Vilares-Morgado ◽  
Elisa Leão-Teles ◽  
Esmeralda Rodrigues ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Genetic Diagnosis ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Mps I ◽  
Sd Oct ◽  
Systemic Therapies

Purpose. To describe retinal findings in a patient with mucopolysaccharidosis type I (MPS I) that underwent an early treatment with hematopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT). Case Report. We describe a case of a 12-year-old female with a biochemical and genetic diagnosis of MPS I. She underwent HSCT and ERT on the first year of life. The visual acuity was 5/10 in both eyes and she had bilateral grade 2 corneal haze. Spectral domain optical coherence tomography (SD-OCT) revealed thickening of the external limiting membrane (ELM) at the fovea. In the parafoveal and perifoveal regions, SD-OCT displayed a loss of the interdigitation, ellipsoid, and myoid zones and of the ELM accompanied by progressive thinning of the outer nuclear layer. Fundus infrared imaging revealed a hyperreflective ring centred on the fovea and hyporeflective areas in temporal parafoveal regions in both eyes. En face OCT imaging revealed two hyperreflective rings on the outer retinal level. Conclusion. This patient developed macular changes with foveal deposition of hyperreflective material and parafoveal thinning, despite early systemic treatment. Systemic therapies can provide an increase in life expectancy and stabilize visual acuity and corneal clouding, although their effect on retinal degeneration is unknown.

Clinical and economic justification of screening for mucopolysaccharidosis type I in children at groups of risks

2021 ◽  
pp. 4-15
Author(s):  
I. S. Krysanov ◽  
V. S. Krysanova ◽  
V. Yu. Ermakova
Keyword(s):  
Average Cost ◽  
Weighted Average ◽  
Economic Assessment ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Selective Screening ◽  
Mucopolysaccharidosis Type I ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Mps I

Background. Mucopolysaccharidosis Type I (MPS I) has clinical heterogeneity without specific symptoms leading to difficulties with diagnostic on time. In-depth screening for MPS I in children has aim of early detection and timely treatment with an enzyme replacement therapy. Aim. The purpose of this study was to conduct a clinical and economic assessment of the feasibility of screening for MPS I in children at group of risks. Materials and methods. Model for evaluation of the social-economic burden of MPS I with calculation of expenditures has been created. Costs of diagnosed and non-diagnosed patients in group of risks were identified, including direct medical costs (pharmacotherapy, out-patient cure, hospital admission, complications treatment, hematopoietic stem cell transplantation; direct non-medical (payments for disability); indirect (expenses related to the reduction or loss of the ability to work of one of the parents performing the duties of caring for a disabled child). Results. The weighted average cost per 1 diagnosed patient with mild forms of MPS I with selective screening, was 405,974.22 rubles, which is 184,421.85 rubles less vs average cost per 1 undiagnosed patient. The management and treatment of patients with mild forms of MPS I after selective screening will allow saving up to 17.7 million rubles/year, which would possible to additionally screen 705 patients. Taking into account the size of the population of patients with undiagnosed MPS I, currently the costs for this group amount to 56.7 million rubles, while the «overspend» of budget funds for untimely diagnosis of MPS I for this cohort of children is about 22.6 million rubles/year. Conclusion. Selective screening for MPS I in children at group of risks is economically proved and can lead to treatment on-time for disability and complications prevention.

Evidence that glycosaminoglycan storage and collagen deposition in the cauda epididymidis does not impair sperm viability in the Mucopolysaccharidosis type I mouse model

2020 ◽  
Vol 32 (3) ◽  
pp. 304 ◽  
Author(s):  
Cinthia Castro do Nascimento ◽  
Odair Aguiar ◽  
Gustavo Monteiro Viana ◽  
Vânia D'Almeida
Keyword(s):  
Sperm Morphology ◽  
Reproductive Age ◽  
Morphologic Change ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Lysosomal Storage ◽  
Enzyme Replacement ◽  
Cauda Epididymidis ◽  
Mps I

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disease caused by a deficiency of the lysosomal hydrolase, α-L-iduronidase (IDUA). IDUA degrades heparan and dermatan sulfates, two types of glycosaminoglycan (GAG), important signalling and structural molecules of the extracellular matrix. Because many cell types store GAGs, MPS I has been investigated in human and animal models. Enzyme replacement therapy is available for MPS I patients and has improved their life expectancy, allowing them to achieve reproductive age. The aim of this study was to evaluate epididymal and sperm morphology and function in a murine model of MPS I. We used C57BL Idua+/+ and Idua−/− adult male mice (6 months old) to investigate epididymal morphology, sperm ultrastructure, GAG characterisation and mating competence. Epithelial GAG storage, especially in the cauda epididymidis, was seen in Idua−/− mice. Regardless of the morphologic change and GAG storage found in the cauda epididymis, sperm morphology and motility were normal, similar to wild types. In the interstitium, vacuolated cells were found in addition to deposits of GAGs. Mating was not impaired in Idua−/− males and litter sizes were similar between groups. At the time point of the disease evaluated, the deficiency in IDUA affected the morphology of the epididymis in male Idua−/− mice, whereas sperm appearance and motility and the male’s capacity to mate and impregnate females were preserved.

scholarly journals Improvement in time to treatment, but not time to diagnosis, in patients with mucopolysaccharidosis type I

2020 ◽  
pp. archdischild-2020-319040 ◽  
Author(s):  
Roberto Giugliani ◽  
Nicole Muschol ◽  
Hillary A. Keenan ◽  
Mark Dant ◽  
Joseph Muenzer
Keyword(s):  
Early Diagnosis ◽  
Age At Diagnosis ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Time To First Treatment ◽  
Mps I ◽  
Over Time

ObjectiveEarly diagnosis and treatment initiation are important factors for successful treatment of mucopolysaccharidosis type I (MPS I). The purpose of this observational study was to assess whether age at diagnosis and time to first treatment for individuals with MPS I have improved over the last 15 years.Study designData from the MPS I Registry (NCT00144794) for individuals with attenuated or severe disease who initiated therapy with laronidase enzyme replacement therapy (ERT) and/or hematopoietic stem cell transplantation (HSCT) between 1 January 2003 and 31 December 2017 were included.ResultsData were available for 740 individuals with attenuated (n=291) or severe (n=424) MPS I (unknown n=25). Median age at diagnosis for attenuated disease did not change over time and ranged between 4.5 and 6 years of age while the median duration from diagnosis to first ERT decreased from 5.6 years before/during 2004 to 2.4 months in 2014–2017. For severe MPS I treated with HSCT, median age at diagnosis was less than 1 year and median time to first treatment was less than 3 months throughout the 15-year observation period.ConclusionsTimes to diagnosis and HSCT initiation for individuals with severe MPS I were consistent over time. For individuals with attenuated MPS I, the time to ERT initiation after diagnosis has improved substantially in the last 15 years, but median age at diagnosis has not improved. Efforts to improve early diagnosis in attenuated MPS I are needed to ensure that patients receive appropriate treatment at the optimal time.

scholarly journals Mucopolysaccharidosis Type I

Diagnostics ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 161 ◽  
Author(s):  
Francyne Kubaski ◽  
Fabiano de Oliveira Poswar ◽  
Kristiane Michelin-Tirelli ◽  
Ursula da Silveira Matte ◽  
Dafne D. Horovitz ◽  
...  
Keyword(s):  
Stop Codon ◽  
Neurological Impairment ◽  
Intermediate Form ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Scheie Syndrome ◽  
Mps I

Mucopolysaccharidosis type I (MPS I) is caused by the deficiency of α-l-iduronidase, leading to the storage of dermatan and heparan sulfate. There is a broad phenotypical spectrum with the presence or absence of neurological impairment. The classical form is known as Hurler syndrome, the intermediate form as Hurler–Scheie, and the most attenuated form is known as Scheie syndrome. Phenotype seems to be largely influenced by genotype. Patients usually develop several somatic symptoms such as abdominal hernias, extensive dermal melanocytosis, thoracolumbar kyphosis odontoid dysplasia, arthropathy, coxa valga and genu valgum, coarse facial features, respiratory and cardiac impairment. The diagnosis is based on the quantification of α-l-iduronidase coupled with glycosaminoglycan analysis and gene sequencing. Guidelines for treatment recommend hematopoietic stem cell transplantation for young Hurler patients (usually at less than 30 months of age). Intravenous enzyme replacement is approved and is the standard of care for attenuated—Hurler–Scheie and Scheie—forms (without cognitive impairment) and for the late-diagnosed severe—Hurler—cases. Intrathecal enzyme replacement therapy is under evaluation, but it seems to be safe and effective. Other therapeutic approaches such as gene therapy, gene editing, stop codon read through, and therapy with small molecules are under development. Newborn screening is now allowing the early identification of MPS I patients, who can then be treated within their first days of life, potentially leading to a dramatic change in the disease’s progression. Supportive care is very important to improve quality of life and might include several surgeries throughout the life course.

scholarly journals Mucopolysaccharidosis Type I: Current Treatments, Limitations, and Prospects for Improvement

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 189
Author(s):  
Christiane S. Hampe ◽  
Jacob Wesley ◽  
Troy C. Lund ◽  
Paul J. Orchard ◽  
Lynda E. Polgreen ◽  
...  
Keyword(s):  
Clinical Manifestations ◽  
Common Disease ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Hurler Syndrome ◽  
Mucopolysaccharidosis Type I ◽  
Lysosomal Disease ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Mps I

Mucopolysaccharidosis type I (MPS I) is a lysosomal disease, caused by a deficiency of the enzyme alpha-L-iduronidase (IDUA). IDUA catalyzes the degradation of the glycosaminoglycans dermatan and heparan sulfate (DS and HS, respectively). Lack of the enzyme leads to pathologic accumulation of undegraded HS and DS with subsequent disease manifestations in multiple organs. The disease can be divided into severe (Hurler syndrome) and attenuated (Hurler-Scheie, Scheie) forms. Currently approved treatments consist of enzyme replacement therapy (ERT) and/or hematopoietic stem cell transplantation (HSCT). Patients with attenuated disease are often treated with ERT alone, while the recommended therapy for patients with Hurler syndrome consists of HSCT. While these treatments significantly improve disease manifestations and prolong life, a considerable burden of disease remains. Notably, treatment can partially prevent, but not significantly improve, clinical manifestations, necessitating early diagnosis of disease and commencement of treatment. This review discusses these standard therapies and their impact on common disease manifestations in patients with MPS I. Where relevant, results of animal models of MPS I will be included. Finally, we highlight alternative and emerging treatments for the most common disease manifestations.

scholarly journals The combined use of enzyme activity and metabolite assays as a strategy for newborn screening of mucopolysaccharidosis type I

2020 ◽  
Vol 58 (12) ◽  
pp. 2063-2072 ◽  
Author(s):  
Giulia Polo ◽  
Daniela Gueraldi ◽  
Antonella Giuliani ◽  
Laura Rubert ◽  
Chiara Cazzorla ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Newborn Screening ◽  
False Positives ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Hematopoietic Stem ◽  
Enzyme Replacement ◽  
Second Tier ◽  
Mps I

AbstractObjectivesMucopolysaccharidosis type I (MPS I) was added to our expanded screening panel in 2015. Since then, 127,869 newborns were screened by measuring α-L-iduronidase (IDUA) enzyme activity with liquid chromatography tandem mass spectrometry (LC-MS/MS). High false positives due to frequent pseudodeficiency alleles prompted us to develop a second-tier test to quantify glycosaminoglycan (GAG) levels in dried blood spot (DBS).MethodsHeparan-sulfate (HS) and dermatan-sulfate (DS) were measured with LC-MS/MS after methanolysis. DBSs were incubated with methanolic-HCl 3 N at 65 °C for 45 min. Chromatographic separation used an amide column with a gradient of acetonitrile and water with 10 mM ammonium acetate in a 9-min run. The method was validated for specificity, linearity, lower limit of quantification (LOQ), accuracy and precision.ResultsIntra- and inter-day coefficients of variation were <15% for both metabolites. Reference values in 40 healthy newborns were: HS mean 1.0 mg/L, 0–3.2; DS mean 1.5 mg/L, 0.5–2.7). The two confirmed newborn MPS I patients had elevated HS (4.9–10.4 mg/L, n.v. <3.2) and DS (7.4–8.8 mg/L, n.v. <2.7). Since its introduction in February 2019, the second-tier test reduced the recall rate from 0.046% to 0.006%. Among 127,869 specimens screened, the incidence was 1:63,935 live births. Both patients started enzyme replacement therapy (ERT) within 15 days of birth and one of them received allogenic hematopoietic stem cell transplantation (HSCT) at ht age of 6 months.ConclusionsGAGs in DBS increased the specificity of newborn screening for MPS I by reducing false-positives due to heterozygosity or pseudodeficiency. Early diagnosis and therapeutical approach has improved the outcome of our patients with MPS I.

scholarly journals Sexual behaviour in a murine model of Mucopolysaccharidosis type I (MPS I)

2019 ◽  
Author(s):  
Ana Beatriz Barbosa Mendes ◽  
Cinthia Castro do Nascimento ◽  
Vânia D’ Almeida
Keyword(s):  
Sexual Behaviour ◽  
Heparan Sulphate ◽  
Adult Life ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Lysosomal Storage ◽  
Cell Functions ◽  
Mps I ◽  
Copulatory Behaviour

AbstractMucopolysaccharidosis Type I (MPS I) is a rare genetic lysosomal storage disease caused by a mutation of IDUA gene. IDUA codes for α-L-iduronidase (IDUA), a lysosomal hydrolase that degrades glycosaminoglycans (GAGs): heparan sulphate and dermatan sulphate. GAGs are structural and signalling molecules that have a crucial role in controlling a variety of cell functions and their interaction with extracellular matrix. Because of GAG’s widespread action in cellular metabolism, MPS I is a progressive and disabling multisystemic disorder. Nowadays, the therapies availability allowed patients to reach the adult life and the consequences of the disease in their reproductive system is still little known. We aimed to investigate whether IDUA disruption influences sexual behaviour and sexual steroid production in male and female MPS I mice. We used 3 and 6-month-old male and 3-month-old female Idua+/_ and Idua−/− mice to evaluate typical rodent copulatory behaviours. In males we observed the frequency and latency of mounts, intromissions and ejaculations. In females we evaluated the lordosis quotient. We also analysed the locomotor capacity of mice in the open field test, since copulatory behaviour requires mobility. We also quantified steroidal hormonal levels in plasmatic samples. We detected an increase in the latencies of intromissions in male copulatory behaviour of Idua−/− males when compared to Idua+/_. However, the number of intromissions was not statistically different between groups. No parameter of female sexual behaviour was statistically different between control and knockout females. In both sexes, we detected diminished mobility in Idua−/− mice. Plasma hormone levels did not differ between Idua+/_ and Idua−/− mice, both in males and females. We concluded that in the considered time point of MPS I progression, mice are able to perform sexual behaviour, but the male performance may be influenced due to the motor disability predicted to MPS I.

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