Figure 3. Analysis of glycosphingolipids in AFT-024 and FDC-P1 cells.

(A) Synthesis of glycosphingolipids in AFT-024 cells. Cell cultures were incubated for 12 h with [¹⁴C]galactose and for the last 12 h of treatment with 10 μM PDMP for 24 or 72 h. (B) Synthesis of glycosphingolipids in FDC-P1 cells. (C) Glycosphingolipids shed by AFT-024 and FDC-P1 cells. Cell cultures were incubated 12 h with [¹⁴C]galactose and the lipids were shed into the medium for 48 h. (D) FDC-P1 uptake of glycosphingolipids from AFT-024 cell-conditioned medium. AFT-024 cultures were incubated for 12 h with [¹⁴C]galactose and the lipids were shed into the medium for 48 h. FDC-P1 cells washed previously with CMF-BSS were then inoculated in RPMI supplemented with 10% (v/v) FBS and 50% (v/v) of medium conditioned by AFT-024 cells. Lipids were extracted, purified, analysed by HPTLC and visualized by fluorography. The radioactive bands correspond to the lipids indicated. CTetH: ceramide tetrahexoside; CTH, ceramide trihexoside; CDH, ceramide dihexoside; CMH, ceramide monohexoside; PC, phosphatidylcoline. Gangliosides are named according to Svennerholm [47].