Gangliosides in human chronic lymphocytic leukaemia

Gangliosides were analysed by elaborated overpressured thin-layer chromatography (OPTLC) in 6 cell samples from 5 patients with chronic lymphocytic leukaemia (CLL) of B-cell origin, and 4 individual lymphocyte preparations from normal blood donors. The principal difference in the ganglioside profile between these two counterparts appears to be the presence of GD3 and the predominance of the less polar compounds (GM3, GM2, GM1) in CLL cells. Qualitatively, GD3 accounted for about 5.5% of the total CLL gangliosides, whereas it was not detectable in normal lymphocytes. Quantitatively, GM3 constituted more than 81% of the total CLL gangliosides, a proportion more than twice as high as that found in normal lymphocytes. Three other minor gangliosides were isolated from CLL cells; these were shown to be GM2 (trace amounts), GM1 (7.7%), and GD1 (4%). The expression of individual gangliosides varied greatly among the various CLL samples obtained from different patients, and even from the same patient, if examined at different times. No gangliosides were found in the supernatant collected from CLL cells subjected to a temperature shift (0 degrees C to 37 degrees C) or in the cell-free medium harvested from the CLL cells kept in overnight culture.