A SIMPLE METHOD FOR SCREENING FOR FARBER-DISEASE ON CULTURED SKIN FIBROBLASTS

Farber disease is an inborn lysosomal storage disorder characterized b y accumulation of ceramide in the patient's tissues due to the deficie nt activity of acid ceramidase, Currently, confirmation of the diagnos is is performed in an extremely limited number of laboratories, We the refore developed a procedure which does not require any particular sph ingolipid substrate and is based on the quantitation of ceramide level s in cultured skin fibroblasts, In the method we devised, the ceramide present in cellular lipid extracts subjected to mild alkaline hydroly sis was quantified using the commercially available diacylglycerol kin ase kit. We show that both primary cultures of skin fibroblasts and SV 40-transformed fibroblasts derived from a series of patients with Farb er disease exhibit ceramide excess as compared to their normal counter parts (2345-17 153 pmol/mg cell protein in Farber cells vs, 432-1298 p mol/mg cell protein in controls). Use of this simple method should gre atly facilitate the biochemical diagnosis of Farber disease.