Glycosphingolipids in murine lymphocytes from thymus and spontaneous and X-ray induced thymomas.
Lymphocytes from spontaneous thymoma in AKR mice and from X-ray induced thymoma in C57B1/6 mice showed elevated levels (by 50% and 100%, respectively) of lipid-bound sialic acid as compared with lymphocytes from normal thymuses used as controls. Some ganglioside fractions in thymomas were elevated 4-6-fold over those in normal thymuses while other fractions decreased or disappeared. Neutral glycosphingolipid (NGSL) content in lymphocytes from thymomas was also changed. Thin-layer chromatography of NGSLs showed that the fractions migrating as ceramide monohexoside (CMH), dihexoside (CDH) and below globoside standards were increased, respectively, 2-3-fold, 3-6-fold and 2-fold in both types of thymomas. Methylation and gas-liquid chromatography analysis confirmed the presence of CMH, CDH and globoside in NGSLs isolated from X-ray induced thymoma.