Isolation and characterization of gangliosides from chronic myelogenous leukemia cells

Gangliosides isolated from the cells of three patients with chronic myelogenous leukemia (CML) were purified by Folch partitioning, diethylaminoethyl Sephadex, Florisil (acetylated gangliosides), and silicic acid chromatography and were structurally analyzed using thin-layer and gas-liquid chromatography, methylation analysis, enzyme degradation, and high-performance liquid chromatography. With these methods, the major gangliosides isolated were II3-alpha-N-acetylneuraminosyl-lactosylceramide, IV3-alpha-N-acetylneuraminosyl-neolactotetraosylceramide (sialosylparagloboside), and a ganglioside with the following structure: NeuAc alpha 2 leads to 3(Gal beta 1 leads to 4 GlcNac beta 1 leads to 3)2Gal beta 1 leads to 4Glc beta 1 leads to 1Cer. This ganglioside has previously been characterized as an "i" active compound. Like normal neutrophils, CML cells contain monosialogangliosides that belong to the lactosyl and neolacto family. However, our study shows that CML cells differed from normal neutrophils in that they contained less total ganglioside, and their major ganglioside species is II3-alpha-N-acetylneuraminosyl-lactosylceramide. Differences between gangliosides of CML and acute nonlymphoblastic leukemias are discussed.