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PubMed1992

Light and electron microscopy of the cornea in systemic mucopolysaccharidosis type I-S (Scheie's syndrome).

A 37-year-old man with coarse facies, stiff joints, corneal clouding, and normal intelligence sought medical attention. The diagnosis of a systemic mucopolysaccharidosis (MPS) type I-S (Scheie's syndrome) was confirmed by the presence of lysosomal alpha-L-iduronidase deficiency and excessive urinary dermatan and heparan sulfate excretion. The corneal button after perforating keratoplasty of the right eye demonstrated mucopolysaccharides consisting of numerous vacuoles containing fibrillogranular and partly membranebound material in epithelial cells, histiocytes, keratocytes, and extracellular matrix. Endothelial cells were distinctly free of storage material. The epithelial basement membrane showed frequent breaks, whereas Bowman's layer was only slightly attenuated. Irregular collagen fibrils and fibrous long-spacing collagen were noted near degenerating distended keratocytes. The Descemet's membrane was normal. The literature of six reported histopathological examinations of the cornea in Scheie's syndrome is reviewed. Detection of fibrous long-spacing collagen seems to be a typical abnormality of the cornea in MPS I-S.

Adult↗
PubMed2006

Epstein-Barr virus-induced transformation of B cells for the diagnosis of genetic metabolic disorders--enumerative conditions for cryopreservation.

Epstein-Barr virus (EBV) infection in vitro causes transformation of B cells and generates B lymphoblastoid cell lines (LCLs). These LCLs have been widely used for the diagnostic of several genetic metabolic disorders. However, up to now, efficiency of LCL generation has been based on misleading subjective analysis. In this study, quantitative analyses have been performed to indicate efficiency of B-cell transformation to measuring human lysosomal acid hydrolases associated with: GM1-gangliosidosis type I, Gaucher disease and mucopolysaccharidosis type I. Peripheral blood mononuclear cells were isolated from 13 subjects, and LCLs were produced by culturing them with EBV for 12 days. Activities of the enzymes beta-galactosidase, beta-glucosidase and alpha-iduronidase were measured before and after cryopreservation in liquid nitrogen for 30 days. Efficiency of the B-cell transformation was screened every 4 days by the enumeration of cell proliferation, cell counts and changes in granularity estimated by flow cytometry. We observed the generation of 13 LCLs. Cell transformation was confirmed by the gradual increase of cellular clusters, cell size and granularity. In addition, we determined that the activity of the enzymes mentioned above did not change following cryopreservation. These data suggest that our enumerative approach for screening of EBV-LCLs is efficient for the enzymatic determination of human lysosomal acid hydrolases and may thus replace misleading subjective analyses.

Adult↗
PubMed2005

Enzyme replacement therapy in mucopolysaccharidosis type I.

UNLABELLED: Mucopolysaccharidosis (MPS) type I is a lysosomal storage disorder caused by deficiency of the enzyme alpha-L-iduronidase (IDUA), which presents with a wide spectrum of phenotypes. Recently, enzyme replacement therapy (ERT) became available for patients with MPS I and has been demonstrated to be safe and effective in patients with the milder Hurler-Scheie and Scheie phenotypes. Treatment for 26 weeks with recombinant human IDUA (laronidase) has been shown to significantly increase the percentage of predicted normal forced vital capacity and the distance walked in the 6-minute walk test. There was also a clear reduction in the volume of the liver and the levels of urinary glycosaminoglycan excretion. The drug was generally well tolerated. There were no drug-related severe adverse events, and although the majority of patients developed IgG antibodies, these declined by the end of the study. CONCLUSION: ERT seems to be a very promising new therapeutic regimen for patients with MPS I, especially for those with the less severe variants. However, as laronidase does not cross the blood-brain barrier it will probably not influence the central nervous manifestations in the most severely affected patients with the Hurler phenotype, although it may improve general lung and heart function, making bone marrow transplantation easier to tolerate.

Bone Marrow Transplantation↗
PubMed1977

Fucosidosis in a native-born Briton.

This investigation reports the biochemical findings in a native-born Briton suffering from the adult form of fucosidosis. Alpha-L-fucosidase, alpha-L-iduronidase, and beta-D-galactosidase were studied in cultured fibroblast and leucocytes from the patient with fucosidosis, her maternal grandfather, and several normal controls. A complete lack of alpha-L-fucosidase activity was found in the patient's fibroblasts and leucocytes while the grandfather exhibited a heterozygous level of alpha-L-fucosidase activity in his leucocytes. Excessive excretion of what is very likely to be a fucose-containing sphingolipid was demonstrated in the patient's urine by thin-layer chromatography. Compared with five isoenzyme forms of alpha-L-fucosidase activity in normal leucocytes, cellulose acetate electrophoresis of the patient's leucocytes produced evidence of a single band of slight activity associated with one of the isoenzymes. This residual activity probably accounts for the survival of such patients into adolescence and beyond.

Adult↗
PubMed1978

Report of a mucopolysaccharidosis occurring in Australian aborigines.

The first 2 reported cases of a mucopolysaccharidosis occurring in an Australian aboriginal family are presented. Though these children had the characteristic morphological features of the Hurler syndrome, enzyme assay of cultured fibroblasts showed normal levels of alpha-L-iduronidase and decreased activity of arylsulphatase B. Thus, they represented the Hurler syndrome clinically, while they had the enzyme defect of the Maroteaux-Lamy syndrome, and they may represent a new severe form of the Maroteaux-Lamy syndrome. The parents of these children were first cousins. Though the children were not full blood aborigines, examination of the pedigree indicates that the gene originated in the common aboriginal family.

Australia↗
PubMed2002

Hurler's syndrome, West's syndrome, and vitamin D-dependent rickets.

Mucopolysaccharidosis I is a metabolic disease of autosomal recessive inheritance caused by deficient activity of alpha-L-iduronidase. The clinical phenotype presents a wide spectrum of signs in the first year of life. We report a child with clinical features and laboratory data consistent with mucopolysaccharidosis I who precociously developed hydrocephalus and flexion spasms with hypsarrythmia in the electroencephalographic registration characteristic of West's syndrome. His radiologic and biochemical data suggested vitamin D-dependent rickets. To our knowledge, this is the first report of a patient demonstrating an association among mucopolysaccharidosis 1, West's syndrome, and vitamin D-dependent rickets.

Chromosome Aberrations↗
PubMed2002

Retrovirally mediated correction of bone marrow-derived mesenchymal stem cells from patients with mucopolysaccharidosis type I.

We have investigated the utility of bone marrow-derived mesenchymal stem cells (MSCs) as targets for gene therapy of the autosomal recessive disorder mucopolysaccharidosis type IH (MPS-IH, Hurler syndrome). Cultures of MSCs were initially exposed to a green fluorescent protein-expressing retrovirus. Green fluorescent protein-positive cells maintained their proliferative and differentiation capacity. Next we used a vector encoding alpha-L-iduronidase (IDUA), the enzyme that is defective in MPS-IH. Following transduction, MPS-IH MSCs expressed high levels of IDUA and secreted supernormal levels of this enzyme into the extracellular medium. Exogenous IDUA expression led to a normalization of glycosaminoglycan storage in MPS-IH cells, as evidenced by a dramatic decrease in the amount of (35)SO(4) sequestered within the heparan sulfate and dermatan sulfate compartments of these cells. Finally, gene-modified MSCs were able to cross-correct the enzyme defect in untransduced MPS-IH fibroblasts via protein transfer.

Adolescent↗
PubMed1985

Comparative enzymology of eleven acid hydrolases in cultured amniotic fluid cells, skin fibroblasts and embryonic lung fibroblasts, and the respective changes with the increasing age of the cell cultures.

Assay conditions were studied for eleven lysosomal enzymes (beta-D-galactosidase, alpha-D-mannosidase, beta-hexosaminidase, beta-D-glucuronidase, alpha-D-galactosidase, alpha-D-glucosidase, arylsulfatase, beta-D-glucosidase, alpha-L-fucosidase, alpha-D-neuraminidase and alpha-L-iduronidase) in cultured amniotic fluid cells (CAFC), cultured skin fibroblasts (CSF) and cultured embryonic lung fibroblasts (CELF), and the properties of the enzymes were compared among these cultured cells. In addition, changes in these enzymes from the three cell types were investigated between 4-6 earlier passages and 24-26 later passages. With the exception of alpha-D-glucosidase, alpha-D-neuraminidase and alpha-L-fucosidase, all enzymes assayed for the 4-6 earlier passages and the 24-26 later passages had the same Km values and the same pH optima, and were also unchanged with the increasing age of cell cultures, with regard to their points. The specific activities of beta-D-glucuronidase, arylsulfatase, alpha-D-glucosidase and beta-D-glucosidase for the 4-6 earlier passages increased significantly with development, though no change was observed with development in the specific activities of other enzymes. Variations were observed between the levels of these enzymes in the three cell types with the increasing age of cell cultures, such as increases in some, decreases in others and no change in still others.

Amniotic Fluid↗
PubMed2005

Laronidase treatment of mucopolysaccharidosis I.

The lysosomal storage disorder (LSD) mucopolysaccharidosis type I (MPS I, McKusick 25280, Hurler syndrome, Hurler-Scheie syndrome, Scheie syndrome) is caused by a deficiency in the lysosomal enzyme, alpha-L-iduronidase (EC 3.2.1.76). MPS I patients can present within a diverse clinical spectrum, ranging from classical Hurler syndrome to attenuated Scheie syndrome. Laronidase (Aldurazyme) enzyme replacement therapy has been developed as a treatment strategy for MPS I patients and has been approved for clinical practice. Here we review the pre-clinical studies and clinical trials that have been used to demonstrate that intravenous laronidase therapy is well tolerated and effective for treating MPS I patients who do not have neuronal pathology. Current challenges for a viable treatment strategy for all MPS I patients include development of an early screening protocol that identifies patients before the onset of irreversible pathology, methods to predict disease severity, appropriate treatment for neuropathology, and an effective patient monitoring regimen.

Adolescent↗
PubMedDate not supplied

Mucopolysaccharidosis type I: clinical and biochemical study.

Of 1240 outpatients referred to the Human Genetics Clinic between 1997 and 1998, 248 (20%) had inborn errors of metabolism, 36 (14%) of which were diagnosed as mucopolysaccharidoses. Parental consanguinity was present in 82% of these patients. Deficiency of alpha-L-iduronidase (IDUA) enzyme in leukocytes and increased urinary mucopolysaccharides excretion were detected in 17 patients. The urinary spot test for glucosaminoglycans was inconclusive in 4 of the 17 cases. Results showed a correlation between the biochemical enzyme activity in leukocytes, the amount of excreted mucopolysaccharides and the subtype and course of mucopolysaccharidosis type I. We conclude that estimation of IDUA enzyme activity in leukocytes can differentiate between clinically overlapping cases of MPS I and MPS II and given the clinical manifestations of MPS I is a definitive and unequivocal method of diagnosis while the urinary spot test is inconclusive.

Case-Control Studies↗
PubMed1979

Mucopolysaccharidosis in a domestic short-haired cat--a disease distinct from that seen in the Siamese cat.

A 10-month-old male domestic short-haired cat was examined because of progressive lameness, a broad face with depressed nasal bridge, small ears, corneal clouding, and multiple bone dysplasia. The cat excreted excessive amounts of glycosaminoglycan (a component of connective tissue) in its urine and had evidence of lysosomal storage of glycosaminoglycans in fibroblasts and neurons. Activity of alpha-L-iduronidase, a lysosomal enzyme involved in glycosaminoglycan degradation, was deficient in cultured fibroblasts and leukocytes. The mucopolysaccharidosis was distinct from that seen in Siamese cats in terms of the pathologic changes and the specific enzyme deficiency.

Animals↗
PubMedDate not supplied

[Mucopolysaccharidosis type I in the Cuban population].

INTRODUCTION: Of all the innate errors of the metabolism, the mucopolysaccharidoses (MPS), a kind of lysosomal disease, are especially significant because of the serious clinical features they give rise to and the therapeutic difficulties they entail. Diagnosis of the index case is essential so that families can gain access to the preventive benefits of genetic counselling. To date, seven types of MPS and 11 enzyme deficiencies have been described. AIMS: Patients with a clinical diagnosis that leads the clinician to suspect they may be suffering from some type of MPS are referred to the Institute of Neurology and Neurosurgery to determine the possible enzyme deficiencies that will provide us with the key to a successful diagnosis. PATIENTS AND METHODS: A total of 588 patients who were clinically suspected of suffering from MPS, in whom 1,502 enzyme analyses were performed in order to classify the type of MPS they were suffering from. The MPS under examination are MPS I, MPS IIIB, MPS IVB, MPS VI and MPS VII. RESULTS: MPS I, or alpha-L-iduronidase deficiency, is the most commonly found with 23 cases (4.08% of the patients studied); 13 were females and the other 10 were males. Of the 23 cases, 10 presented the severe Hurler phenotype with mental retardation, five had the Scheie phenotype with preserved intelligence and eight displayed the intermediate Hurler-Scheie phenotype. Diagnosis was reached before the end of the first year in eight patients, between 1 and 5 years in nine of them and between 6 and 10 years in two cases. Enzyme activity in leucocytes was significantly lower in patients as compared to a control group and with respect to the parents (heterozygotes), and even comparing these to the control group, with a slight and expected overlap. CONCLUSION: The biochemical methodology used allows us, then, to reach a sure biochemical diagnosis and to offer the families the benefits of genetic counselling.

Child↗
PubMed1978

[Mucopolysaccharidosis V (Ullrich-Scheie syndrome) (author's transl)].

Mucopolysaccharidosis V (Scheie's syndrome, MPS-IS) is a very rare, autosomal recessively inherited metabolic disease. The degradation of dermatan sulphate and heparan sulphate is disturbed due to alpha-L-iduronidase deficiency, leading to intracellular storage and excessive urinary secretion of these substances. The characteristic clinical features are contractures (claw-like flexion of the fingers), umbilical and inguinal herniae, corneal opacity, hepatomegaly, myocardiopathy and minor skeletal malformations. A patient with Scheie's syndrome is now reported for the first time in Austria; the results of the clinical, biochemical, chromosomal, dermatoglyphic and electron optical investigations are described and discussed.

Adolescent↗
PubMed1979

[Corneal changes in Scheie disease. (Mucopolysaccharidosis type I S) (author's transl)].

Bilateral keratoplasty performed on a 39-year-old patient with Scheie disease gave the opportunity to study the histological, histochemical and ultrastructural lesions of both corneas. The patient showed all the characteristics signs of Scheie disease with bilateral corneal opacities, thick face, synophrys, mitral and aortic valve stenosis, bilateral carpal tunnel syndrome, stiff joints, and was of normal intelligence. 24 hours urines revealed a marked excretion of mucopolysaccharides. Histology showed scarring of the superficial stroma. Histochemistry revealed an accumulation of acid mucopolysaccharides in the keratocytes throughout the stroma. Electron microscopy showed vacuoles or pleomorphic inclusions in the keratocytes compabible with abnormal lysosomes deficient in alpha-L-iduronidase.

Adult↗
PubMedDate not supplied

[Mucopolysaccharidosis IS: Scheie's syndrome. A report of 2 brothers].

We describe two brothers affected by MPS type IS (Scheie syndrome). Mucopolysaccharidosis type I consists of three clinical entities of varying severity, all due to alfalevo-iduronidase enzyme deficiency. The MPS IS in characterized by joint stiffness, aortic valve disease and corneal clouding. The intellect is normal. All these findings are present on our brothers; furthermore retinal degeneration also occurred. It could give in the future attendant deterioration of vision.

Child↗
PubMed1989

Retinal pigment epithelial glycosaminoglycan metabolism: intracellular versus extracellular pathways. In vitro studies in normal and diseased cells.

The synthesis and turnover of glycosaminoglycans (GAGs) in different fractions of cultured feline retinal pigment epithelium (RPE) were characterized. In one method of fractionation, trypsin was used to separate the extracellular components (referred to as trypsin-soluble glycocalyx) from the intracellular components. As a second method, the basal extracellular matrix (basal ECM) was separated from the rest of the GAGs (cell-associated GAGs) by extracting the cell layer with NH4OH. The incorporation of 35SO4 into cetylpyridinium chloride-precipitable GAGs in the cell-associated and the intracellular fractions increased throughout the labeling period, while in the trypsin-soluble glycocalyx and the basal ECM incorporation approached a maximum. While heparan sulfate was the predominant GAG in all compartments, most was located extracellularly. The majority of dermatan sulfate was localized in the intracellular fraction. GAGs in the trypsin-soluble glycocalyx exhibited a rapid rate of turnover, while GAGs in the intracellular compartment and basal ECM turned over much more slowly. Ascorbic acid increased the incorporation of 35SO4 into ECM chondroitin sulfate/dermatan sulfate, but not heparan sulfate, on a per cell basis. Cycloheximide reduced incorporation of 35SO4-GAGs into both the cell-associated compartment and the basal ECM. In contrast, monensin caused a reduction in basal ECM GAGs while increasing the GAGs in the cell-associated compartment. The intracellular accumulation of GAGs and resultant pathology in alpha-L-iduronidase (alpha-L-id)-deficient RPE indicated that this pathway for the intracellular degradation of GAGs is important in normal RPE function. However, the turnover of GAGs in the trypsin-soluble glycocalyx was not affected by deficient alpha-L-id activity or by the subsequent intracellular accumulation of GAGs. Therefore, normal lysosomal activity in the RPE is not a prerequisite for maintaining the rate of extracellular GAG turnover within normal limits.

Animals↗
PubMed1985

Disease expression in cultured pigment epithelium. Feline mucopolysaccharidosis VI.

Primary cultures of retinal pigment epithelial (RPE) cells from cats with mucopolysaccharidosis VI (MPS VI) have been initiated from mixed populations of cells (ie, derived from the entire eyecup and represented by both pigmented and nonpigmented RPE cells). The cells were enzymatically dissociated from the eyecup and seeded at 6 X 10(4) cells/cm2. Cells from normal and affected cats formed confluent monolayers of polygonal cells between 5-10 days in culture and maintained most of their in vivo morphologic characteristics. The only abnormality observed in the MPS VI-affected cultures was the accumulation of vacuolated intracytoplasmic inclusions; when numerous, these vacuoles caused cellular hypertrophy. Hypertrophy was present only in cells devoid of pigment. Pigmented cells adjacent to or near the hypertrophied cells exhibited little or no accumulation of vacuoles. The inclusions were indistinguishable from those observed in vivo in terms of size, distribution, and appearance. The MPS VI-affected RPE exhibited deficient arylsulfatase B (ASB) activity (RPE-ASB activity: normal = 506 nmol/hr/mg protein; affected = 22 nmol/hr/mg protein), whereas the activities of two other lysosomal enzymes, arylsulfatase A and alpha-L-iduronidase, were normal. A method was developed to initiate primary cultures of RPE cells from defined regions of normal and MPS VI-affected eyes. Studies indicated that cultures initiated from superior-equatorial regions (RPE nonpigmented) contained more vacuolated cytoplasmic inclusion than those initiated from inferior-equatorial regions (RPE pigmented). These findings indicated that the spatial distribution characteristic of the disease in vivo was maintained in culture and that disease expression was inversely correlated with pigmentation.

Animals↗
PubMed1985

Transplantation of amniotic epithelial membranes in patients with mucopolysaccharidoses.

This paper reports the biochemical results of transplanting human amniotic epithelial cells in 3 children with Hunter's and 2 with Hurler's disease. A transient and modest increase of alpha-L-idurono-2-sulphate sulphatase or alpha-iduronidase was observed in the white cells collected from 1 patient with Hunter's and 1 with Hurler's disease. No variation in the excretion of glycosaminoglycans or oligosaccharides was detected in all 5 patients. There was no evidence of immune response towards the transplanted cells or the specifically deficient enzyme. Thus, in spite of the absence of the major histocompatibility antigens, HLA A, B, C and DR, on the surface of the amniotic epithelial cells, no long-term correction of lysosomal enzyme deficiencies was achieved by transplanting amniotic epithelial membranes collected at the end of the gestational period.

Amnion↗