Fig. 6.

Ceramides generated via the de novo pathway are not responsible for DC apoptosis. (A) The de novo ceramides biosynthesis was blocked with Fumonisin B1 (50 μg/mL). These inhibitors were added at the beginning of cell culture in the presence or absence of gangliosides. (B) GM3 ganglioside induced an accumulation of ceramides via the acid SMase pathway. Acid sphingomyelinase inhibited by desipramine (1 μM) was added in the presence or absence of gangliosides every 2 days during cell culture. Results are representative of four independent experiments.