Effect of SACLAC exposure on SL composition in HL-60/dnr cells. A: Long-chain bases. B: Ceramides. C: dh-ceramides. D: GC molecular species. E: SM molecular species. HL-60/dnr cells (800,000/ml dnr-free, RPMI-1640 medium, 10% FBS) were exposed to 10 μM SACLAC (DMSO vehicle) or DMSO (control) for 28 h. DMSO did not impact cell viability. Cells were then harvested by centrifugation, washed three times in PBS, and frozen at −80°C until evaluation by MS. Viability in SACLAC-treated cells was 80% at harvest. Data are expressed as fold changes compared with untreated controls. Sph, sphingosine.