ganglioside--gd1a and Lymphoma

The aim of the present study was to investigate the ganglioside expression of the highly metastatic murine lymphoreticular tumour cell line MDAY-D2. Cells were propagated under controlled pH conditions and oxygen supply in bioreactors of 1 and 7.5 l volumes by repeated batch fermentation. Gangliosides were isolated from 2.7 x 10(11) cells, purified by silica gel chromatography and separated into mono- and disialoganglioside fractions by preparative DEAE anion exchange high performance liquid chromatography. Individual gangliosides were obtained by preparative thin layer chromatography. Their structural features were established by immunostaining, fast atom bombardment and gas chromatography mass spectrometry. In addition to gangliosides of the GM1a-pathway (GM2, GM1a and GD1a) and GM1b (IV3Neu5Ac-GgOse4Cer) and GalNAc-GM1b of the Gm1b-pathway, the disialoganglioside GD1 alpha (IV3Neu5Ac, III6Neu5Ac-GgOse4Cer) was found in equal amounts compared to GD1a (IV3Neu5Ac, II3Neu5Ac-GgOse4Cer). All gangliosides were substituted with C24:0, 24:1 and C16:0 fatty acids, sphingosine and N-acetylneuraminic acid as the sole sialic acid.

Topics: Animals; Carbohydrate Sequence; Cell Line; Chromatography, High Pressure Liquid; Chromatography, Ion Exchange; Chromatography, Thin Layer; Gangliosides; Gas Chromatography-Mass Spectrometry; Lymphoma; Mice; Molecular Sequence Data; Neoplasm Metastasis; Neuraminidase; Oligosaccharides; Sialic Acids; Spectrometry, Mass, Fast Atom Bombardment; Tumor Cells, Cultured

Glycolipids of murine lymphoma cell lines with low metastatic (Eb) and high metastatic (ESb) potentials have been investigated. The Eb cell line was characterized by a high quantity of gangliotriaosylceramide (Gg3), gangliotetraosylceramide (Gg4), GM1b, and a new type of disialoganglioside, termed GD1 alpha. In contrast, the high metastatic ESb cell line was characterized by the absence of these glycolipids and instead by the presence of GM3, GM2, GM1a, GD1a, and GD1b gangliosides. A clear cell surface reactivity with monoclonal antibody anti-Gg3 (2D4) was observed only in Eb cells. Thus, Eb cells are distinct from ESb cells in their ability to add the GalNAc residue to LacCer, supplying Gg3 for synthesis of a series of glycolipids via an asialogangliotetraosyl pathway, while ESb cells are capable of synthesizing GM3, which initiates synthesis of ganglio-series gangliosides GM2, GM1a, GD1a, and GD1b. While disialogangliosides of ESb cells were identified as GD1a and GD1b, a disialoganglioside isolated from Eb cells was characterized as having a novel structure (referred to as GD1 alpha) as follows: (formula; see text) Thus, Eb and ESb cells are clearly different in their qualitative sialylation patterns, i.e., the position of sialic acid residues. Cell surface labeling with galactose-oxidase/NaB[3H]4 revealed a high exposure of Gg3 and Gg4 at the Eb cell surface, while both labels were absent in ESb cells. In contrast, ESb cells showed a substantial label at GM1a, which was greatly enhanced after sialidase treatment.

Topics: Animals; Antibodies, Monoclonal; Carbohydrate Sequence; Chromatography, Thin Layer; Gangliosides; Glycolipids; Lymphoma; Membrane Lipids; Mice; Neoplasm Metastasis; T-Lymphocytes