Experimental studies on the pathogenesis of leucodystrophies. I. The effect of intracerebrally injected sphingolipids in the rat's brain

Disialoganglioside GD2 in human neuroectodermal tumor cell lines and gliomas

Monoclonal antibodies (mAbs) recognizing the disialoganglioside II3(NeuAc)2GgOse3Cer (GD2) were produced by immunizing mice with the GD2-expressing neuroblastoma cell line LAN-1 and a prefusion boost with purified GD2 coupled to Salmonella minnesota. Two IgM mAbs were isolated which demonstrated high levels of reactivity (binding ratios in excess of 100) with GD2 by solid-phase radioimmunoassay and positivity in high-performance thin-layer chromatography (HPTLC) immunostain; only one (DMAb-20) was subsequently shown by analysis with a panel of defined ganglioside species to be specific for the minimum epitope of GD2 GalNAc beta 1-4(NeuAc alpha 2-8-NeuAc alpha 2-3)Gal-, DMAb-20 was used to evaluate the expression of GD2 by malignant glioma and medulloblastoma cell lines using cell surface radioimmunoassay. indirect membrane immunofluorescence. HPTLC immunostain, and densitometric analysis of extracted gangliosides from selected cell lines. Sixteen of 20 (80%) malignant glioma and 5 of 5 medulloblastoma cell lines reacted with DMAb-20; in agreement with previous studies, 5 of 5 neuroblastoma and 2 of 3 melanoma cell lines also reacted with DMAb-20, GD2 was proportionally increased in the glioma and medulloblastoma cell lines relative to levels in normal brain, as determined by densitometric analysis. In a phenotypic survey of malignant glioma biopsies, tumor cells in 24 of 30 (80%) cases stained positively with DMAb-20. Reactive astrocytes, both within the adjacent to tumors, were frequently intensely stained. Among the morphological variants of glioblastoma examined, the most intense staining with DMAb-20 was observed in neoplastic gemistocytes, with the weakest or absent staining in small cell glioblastomas. As GD2 is a commonly expressed surface antigen of gliomas and medulloblastomas, expression of which is retained in tissue culture. DMAb-20 will be useful in determining the functional role of GD2 in cell-cell interaction, adhesion, and invasion, and in defining altered growth control mechanisms of central nervous system neoplasms in in vitro models.

Adult type of leukodystrophy. Krabbe's disease?

A 24-year-old man developed progressive dementia in seven years. The patient suffered a severe bronchopneumonia and eventually died few days later. Brain coronal sections showed a soft gray-brownish discoloration of white matter of centrum ovale but the subcortical arcuate fibers and the interne capsule were preserved. Microscopically, the white matter showed marked loss of myelin and oligodendrocytes, abundant hypertrophic astrocytes and numerous "globoid cells". The latter showed strong positivity in immunostains for a mouse monoclonal antigalactocerebroside antibody. The presence of these cells in the brain white matter might be the morphological basis to classify the present case as one of Krabbe's Leukodystrophy.

A case of Krabbe's leukodystrophy without globoid cells

Krabbe's globoid cell leukodystrophy is a rare hereditary progressive neurological disease of infants, in which there is deficient activity of galactosylceramide beta-galactosidase. The pathological hallmark is the presence of multinucleated globoid cells in the white matter associated with severe myelin depletion and gliosis. We report a second case where galactosylceramide beta-galactosidase deficiency was proven but no globoid cells were found in the brain. Symptoms began within the first 10 months of life and a deficiency of galactosylceramide beta-galactosidase activity was demonstrated in peripheral blood leukocytes and skin fibroblasts. The child survived till 8 yrs 7 mths. The reason for the absence of globoid cells is not clear but may be related to different effects of the gene mutation on the four substrates or possibly the interaction of sphingolipid activator protein-2.

Demyelination in the spinal cord of murine globoid cell leukodystrophy (the twitcher mouse)

Chronologic events of demyelination were investigated in the spinal cord of the twitcher mouse, an authentic murine model of human globoid cell leukodystrophy (GLD) from 5 to 45 days postnatal. There was very little evidence of myelin degeneration before day 25 although clustered or scattered globoid cells were already noted in the dorsal columns and intramedullary portion of the ventral roots. Globoid cells contained typical cytoplasmic inclusions and in those which were found adjacent to degenerating myelin and naked axons, myelin debris were conspicuous in their cytoplasm. Vesiculation of myelin and a feature of globoid cells stripping myelin lamellae were noted in the area of demyelination. Myelin and oligodendroglial degeneration became pronounced throughout the spinal white matter after day 40 but globoid cells tended to be more concentrated in the dorsal columns. Our observations suggest that the emergence of globoid cells in GLD is in response to the changes in biochemical environment (i.e., excessive presence of galactosylceramide in the tissue?), and these cells appear to have a role as phagocytic cells in removing myelin lamellae.

The twitcher mouse: an ultrastructural study on the oligodendroglia

Morphological alterations of oligodendroglia were investigated in the spinal cord of the twitcher mouse, an authentic murine model of human globoid cell leukodystrophy (GLD) from day 5 to day 45 postnatal (p.n.). Typical inclusions were seen in the perikarya as well as the processes of oligodendroglia after day 10 with increasing frequency. The majority of the inclusions was non-crystalloid but rather needle-like or slender tubular in appearance. Ultrastructural features of cellular degeneration became first noticeable on days 25-30 in the oligodendroglial cytoplasm. These consisted of an increased number of microtubules and/or smooth cisterns, dispersed ribosomes, alteration of endoplasmic reticulum forming stacked lamellae or whorls, vesiculation or vacuolation of cytoplasm. The number of degenerating oligodendroglia increased in the older twitcher mice, so did the degenerating myelin sheath. However, even on day 45, when globoid cells became conspicuous in subpial and perivascular regions, many oligodendroglia and myelin sheaths were still well preserved. These observations suggested that oligodendroglial degeneration resulted in the degeneration of myelin sheaths but globoid cells appeared even before morphological evidence of myelin degeneration, presumably in response to the biochemical alterations resulted from the deficiency of galactosylceramidase.

Krabbe's disease. A light and electron microscopic study

Ultrastructural studies of brain and sural nerve biopsy specimens from a patient with Krabbe's disease disclosed periodically constricted or twisted tubules in addition to the more abundant and characteristic crystalloid and prismatic structures within macrophages. It is suggested that the twisted tubules may result from the intracellular accumulation of lactosyl ceramide. Familiarity with these unusual tubular structures is of practical as well as theoretical importance since they may be encountered in brain and peripheral nerve biopsy specimens obtained for the morphological diagnosis of Krabbe's disease.