Farber bodies found in murine phagocytes after injection of ceramides and related sphingolipids

Mice were injected subcutaneously with a single dose of sphingolipids. The sphingolipids tested were: ceramide with alpha-hydroxy fatty acids, ceramide with non-hydroxy fatty acids, glucocerebroside, sphingomyelin, and galactocerebroside. Lipids without sphingolipids served as a control. The mice were sacrificed 1, 2, 3, 4, 5 and 7 days after injection. Three mice were used for each experiment. The subcutaneous tissue at the injected area, the liver and the spleen were studied histologically. At 1-3 days after injection, numerous cytoplasmic inclusion bodies were observed in the macrophages and fibroblasts in the subcutaneous tissue, but not in the liver or the spleen. Ultrastructural studies of the inclusion bodies indicated that the sphingolipids taken up by the phagocytes retained their respective original shape during the 1-3 day stage. At days 4 and 5, the number of the inclusion bodies decreased, but they contained Farber bodies, i.e. curvilinear bodies 12 to 25 nm wide and up to 120 nm long. The mice with galactocerebroside were an exception, with parallel leaflets structures, but without the Farber bodies.