Biochemical and ultrastructural studies on an Epstein-Barr virus-transformed lymphoid cell line from a Niemann-Pick disease type C patient.
Human lymphoid cell lines established from normal subjects and from a Niemann-Pick disease type C patient were investigated from a triple point of view of enzymology, metabolism and ultrastructure: Sphingomyelinase activities, isoenzyme electrofocusing profiles and properties of the major enzyme were quite similar in type C and normal lymphoid cell lines. Similarly, no significant difference was observed in non-specific phosphodiesterases hydrolysing bis(methylumbelliferyl)phosphate and bis(methylumbelliferyl)pyrophosphate. The study of the lipid composition of type C cells showed no obvious accumulation of sphingomyelin or other phospholipid, but only a higher amount of glycolipids (mainly GlcCer and GbOse3Cer), as visualized by bidimensional thin-layer chromatography. Ultrastructural studies demonstrated, in type C cells, the presence of an obvious lysosomal storage of amphiphilic lipids quite similar to that observed in tissues of type C patients. These studies, which demonstrate the validity of lymphoid cell lines as an experimental model system for type C disease, agree with the current opinion that an impairment of sphingomyelin catabolism is not the primary defect in type C disease.
D002460:Cell Line; D002472:Cell Transformation, Viral; D004854:Herpesvirus 4, Human; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006923:Hymecromone / Q000031:analogs & derivatives*; D007527:Isoenzymes / Q000032:analysis; D008055:Lipids / Q000032:analysis; D008214:Lymphocytes / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D009542:Niemann-Pick Diseases / Q000378:metabolism* / Q000473:pathology; D010727:Phosphoric Diester Hydrolases / Q000032:analysis; D013108:Sphingomyelin Phosphodiesterase / Q000032:analysis; D013109:Sphingomyelins / Q000378:metabolism; D014468:Umbelliferones / Q000378:metabolism
D007527:Isoenzymes; D008055:Lipids; D013109:Sphingomyelins; D014468:Umbelliferones; D006923:Hymecromone; C041066:bis(4-methylumbelliferyl)pyrophosphate; D010727:Phosphoric Diester Hydrolases; D013108:Sphingomyelin Phosphodiesterase