Accumulations of N acetyl glucosamine containing glycolipids in erythrocyte stroma of patients with congenial dyserythropoietic anemia type II (HEMPAS)
Congenital Dyserythropoietic Anemia Type II (HEMPAS) is characterized by ineffective erythropoiesis, erythroblastic multinuclearity, increased erythrocyte reactivity with anti i serum, and shortened survival time of the erythrocyte in the peripheral circulation. A recent study demonstrated large accumulations of ceramide di, tri, and tetrahexosides in HEMPAS stroma. Structural determinations of the carbohydrate moieties of HEMPAS glycolipids utilizing specific glycosidases and combination gas liquid chromatographic and mass spectral analysis have been performed. The ceramide trihexoside from HEMPAS stroma consists of a mixture of galactose αl → 4 galactose β1 → 4 glucose ceramide and N acetyl glucosamine β1 → 3 galactose β1 → 4 glucose ceramide. In normal stroma the former compound was the only ceramide trihexoside detected. In addition, 25% of HEMPAS ceramide tetrahexoside is composed of a N acetyl glucosamine containing glycolipid, presumably paragloboside. These alterations of membrane glycolipids may be related to the abnormalities in survival and immunologic reactivity of HEMPAS erythrocytes.
