Glycosphingolipids in Cultured Human Skin Fibroblasts

作者：Glyn Dawson, Reuben K. Matalon, Albert Dorfman · 发表于：Journal of Biological Chemistry · 年份：1972 · DOI：10.1016/s0021-9258(19)44849-7 · 被引用次数：102 · 研究领域：Glycosylation and Glycoproteins Research、Lysosomal Storage Disorders Research、Sphingolipid Metabolism and Signaling

Abstract Fibroblasts cultured from human skin or bone marrow biopsies contain the glycosphingolipids associated with human visceral organs, namely, glucosylceramide (GL-1a), lactosylceramide (GL-2a), trihexosylceramide (GL-3), globoside (GL-4), Gm3 and Gd3. The presence of large amounts of GL-3 and GL-4 distinguishes normal human fibroblasts from most other normal mammalian cell lines so far investigated. Neither gangliosides (glycosphingolipids containing both sialic acid and hexosamine) nor sulfatides appeared to be present in these cells (concentration less than 0.01 µmole per g dry weight of cells). The glycosphingolipids constitute about 3% of the total lipid of fibroblasts, an amount comparable to that of normal human tissue. Further, the glycosphingolipid composition and concentration are largely independent of the amount of serum supplement. Confluent fibroblast cultures showed maximum incorporation of isotope from uniformly labeled d-[U-14C]glucose into the hexose, sphingosine, and fatty acid moieties of all six glycosphingolipids after 24 to 48 hours, indicating de novo synthesis of all three moieties. The half-life of 2 to 3 days was consistent with values generally accepted for membrane-bound phospholipids.