The ganglioside GD1 alpha' IV3Neu5Ac, III6Neu5Ac-GgOse4Cer, is a major disialoganglioside in the highly metastatic murine lymphoreticular tumour cell line MDAY-D2

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.