Appearance of a Novel Type of Ganglioside (GD1α) in a Differentiation-Resistant Clone of Mouse Myeloid Leukemia Cells, M1-R1

Abstract

Glycolipid compositions of three mouse myeloid leukemia cell clones, two that are sensitive to differentiation inducers (M1-T22 and M 1-S1) and one that is differentiation-resistant (M1-R1), have been compared. The T22 and S1 clones contained glucosylceramide (GlcCer), lactosylceramide (LacCer) and gangliotriaosylceramide (Gg₃Cer) as the major neutral glycolipids. The differentiation resistant clone, R1, was characterized by the appearance of globotriaosylceramide (Gb₃Cer) and a decrease of Gg₃Cer. There was a distinct difference in the ganglioside profile between the differentiation-inducible and-resistant clones: T22 and S1 cells contained no detectable amounts of ganglioside, whereas six different gangliosides were detected in the R1 clone. These gangliosides were isolated and identified as GM₃, GM₂, GM_1a, GD_1a, GMib, and a unique disialoganglioside, GD_1a, having the following structure:
Sialic acid α2 6
GalNAcβ1-4Ga1β1-1Cer.
Sialic acid α2-3Gal 3
Based on these comparative studies, the relationship between the glycolipid composition and the differentiation potential of leukemia cells is discussed.