查看文章

The role of acidic glycosphingolipids in cell growth and differentiation was investigated using the multipotent leukemia cell line K562. When GM₃ was added to cell culture media, the growth of K562 cells was remarkably inhibited and the cells were shown to have megakaryocytoid morphology. Ultrastructural study demonstrated that K562 cells treated with GM₃ had platelet peroxidase-positive structures, which were considered to be the specific marker of megakaryocyte. Furthermore, AP-3 directed against an epitope present on membrane glycoprotein IIIa reacted with the GM₃-treated cells. Free N-acetylneuraminic acid, GM₁, GM₂, GD_1a, and a mixture of bovine brain gangliosides containing GD_1a and GT_1b did not affect growth of K562 cells or show morphological changes. According to chemical analyses, GM₃ content increased in megakaryocytoid differentiation induced by tetradecanoylphorbol-13-acetate …