Fucosidosis in a native-born Briton

Fucosidosis revisited: a review of 77 patients

Fucosidosis is a rare, autosomal recessive, lysosomal storage disorder caused by a severe deficiency of alpha-L-fucosidase in all tissues. We have conducted a review of fucosidosis, compiling data from published reports and an international questionnaire survey. Seventy-seven patients affected with fucosidosis of which 19 had not been reported before have been identified. A major aim of the present study was to define the natural history of fucosidosis. The clinical picture of fucosidosis consists of progressive mental (95%) and motor (87%) deterioration, coarse facies (79%), growth retardation (78%), recurrent infections (78%), dysostosis multiplex (58%), angiokeratoma corporis diffusum (52%), visceromegaly (44%), and seizures (38%). Whereas the original fucosidosis patients described by Durand et al. (J. Pediatr 75:665-674, 1969) were decerebrate and died before age 5 years, most fucosidosis patients have a slower course of degeneration. Mortality before age 5 years was observed in only 7 patients (9%), whereas 36 patients (64%) reached the second decade. We did not find evidence for the existence of clinical heterogeneity with a rapidly progressive type I and a slowly progressive type II fucosidosis as suggested in the literature. Instead, there seems to exist a wide continuous clinical spectrum. At the biochemical level no heterogeneity in residual fucosidase enzyme activity or cross-reacting immunoreactive fucosidase protein was observed. At the DNA level at least 4 different mutations must be responsible for fucosidosis. These genotypic differences however do not explain the observed phenotypic differences.

Canine alpha-L-fucosidase in relation to the enzymic defect and storage products in canine fucosidosis

Canine liver alpha-L-fucosidase was purified to apparent homogeneity by affinity chromatography on agarose-epsilon-aminohexanoyl-fucopyranosylamine. It is composed of multiple forms of a common active subunit of 45-50 kDa, which can aggregate in different combinations to form polymers, predominantly dimers. Antiserum was raised against the purified enzyme. There is negligible residual alpha-L-fucosidase in the tissues of English springer spaniels with the lysosomal storage disease fucosidosis. Although no alpha-L-fucosidase protein was detected by Western blotting or by the purification procedure in the affected tissues, some enzymically inactive cross-reacting material was detected in both normal and affected tissues. This suggests that another protein without alpha-L-fucosidase activity was co-purified with the enzyme. Dog liver alpha-L-fucosidase was precipitated by goat anti-(human liver alpha-L-fucosidase) IgG, indicating homology between the enzymes in the two species. Two purified storage products isolated from the brain of a dog with fucosidosis were used as natural substrates for various preparations of canine liver alpha-L-fucosidase. Analysis of the digestion mixtures by t.l.c. and fast-atom-bombardment mass spectrometry suggests that canine alpha-L-fucosidase acts preferentially on the alpha-(1-3)-linked fucose at the non-reducing end and that removal of alpha-(1-6)-linked asparagine-linked N-acetylglucosamine is rate-limiting in the lysosomal catabolism of fucosylated N-linked glycans.

Infantile type 2 sialidosis in a Pakistani family--a clinical and biochemical study

Two siblings of consanguineous parents presented in infancy with failure to thrive, mild coarsening of facies, visceromegaly and corneal opacities. One showed reduced hepatic beta-galactosidase activity suggesting a GM1-gangliosidosis variant. Both patients developed progressive coarsening of facies, slow neurological deterioration, macular cherry-red spots and punctate cataracts over the first decade. Urine screening with thin layer chromatography revealed abnormal excretion of two slow-moving oligosaccharide bands and leukocyte and fibroblast neuraminidase activity was grossly reduced. The mother, phenotypically normal, showed levels of neuraminidase compatible with heterozygosity. These patients have primary neuraminidase deficiency. The clinical and biochemical variables are reviewed.

Radioimmunoassay determination of decreased amounts of alpha-L-fucosidase protein in fucosidosis

Purified human liver alpha-L-fucosidase (EC 3.2.1.51) has been radioiodinated by a chloramine-T procedure to a specific activity of 3.7 . 10(6) dpm/micrograms protein without altering its apparent Michaelis constant for the 4-methylumbelliferyl substrate. This 125I-labeled alpha-L-fucosidase has been used in development of a competitive binding radioimmunoassay for alpha-L-fucosidase which can detect 1-2 ng of enzyme protein and has been employed to quantify the amount of alpha-L-fucosidase protein in the liver and spleen from a patient with fucosidosis. Less than 1% of the normal amount of alpha-L-fucosidase protein is present suggesting that normal amounts of catalytically inactive alpha-L-fucosidase are not found in this disease.

Fucosidosis: severe phenotype with survival to adult age

A male patient with fucosidosis exhibited the following characteristics: 1. Early onset and rapid progression of neurological symptoms. 2.Skin changes compatible with angiokeratoma corporis diffusum. 3. Complete or nearly complete deficiency of alpha-fucosidase. 4. Survival to adult age (20 years). The deficiency of alpha-fucosidase was demonstrated in liver, tears, urine, sediment, and cultured fibroblasts. We conclude that severe deficiency or complete absence of alpha-fucosidase does not by itself preclude survival to adult age.

Purification and characterization of alpha-L-fucosidase from the liver of a fucosidosis patient

alpha-l-Fucosidase was partially purified from the liver of a fucosidosis patient by column chromatography either on agarose-epsilon-aminohexanoylfucosamine or on concanavalin A-Sepharose, despite no apparent enzymic activity in the crude liver supernatant. Mixing studies indicated that the liver of the fucosidosis patient did not lack activators or contain inhibitors of alpha-l-fucosidase activity. The partially purified alpha-l-fucosidase from the liver of the fucosidosis patient exhibits a 4-5-fold-increased Michaelis constant for the 4-methylumbelliferyl substrate (700-750mum) and a greatly decreased thermostability at 55 degrees C compared with the normal liver enzyme. The pH-activity curve is similar to that for the normal enzyme between pH5 and 8, but quite dissimilar in the acid region (pH3.0-4.5): below pH4.5 the alpha-l-fucosidase shows no activity, whereas the normal enzyme retains considerable activity (>/=50% of maximal activity). Isoelectric focusing of the alpha-l-fucosidase revealed one major form with pI5.8 and other possible minor forms. No cross-reacting material was detected when the alpha-l-fucosidase was run in double-immunodiffusion experiments against the immunoglobulin-G fraction of anti-(alpha-l-fucosidase) antibodies, but the enzyme was immunoprecipitated by this immunoglobulin-G fraction. For at least the fucosidosis patient being studied here, all the data suggest retention of a thermolabile portion of normal alpha-l-fucosidase (with characteristic Michaelis constant and pH-activity curve) or production of a kinetically altered alpha-l-fucosidase with decreased catalytic activity but antigenic similarity to the normal enzyme.

Angiokeratoma corporis diffusum with features of a mucopolysaccharidosis

Two cases of angiokeratoma corporis diffusum with mental retardation and some features of a mucopolysaccharidosis have been investigated biochemically, histopathologically, and by electron microscopy. It is submitted, on this evidence, that they are examples of a hitherto undescribed form of lysosomal enzyme deficiency disease.