Transmission electron microscopy images providing information on the internal ultrastructure of SNO cells propogated in medium only and SNO cells treated with DMSO. (A) Cells propogated in medium only, (B) cells exposed to DMSO – vehicle control, (C) cells exposed to actinomycin D – positive control and (D) cells exposed to ESE-16 at a concentration of 0.2 μM. Both the cells propogated in medium and the vehicle control cells showed microvilli protruding from their cell membrane surface. The nuclear membrane is smoothly outlined and well-preserved cytoplasmic organelles are visible. The positive control for apoptosis showed loss of microvilli, membrane blebbing and the presence of apoptotic bodies. ESE-16-treated cells revealed a decrease in nuclear membrane definition, membrane blebbling and apoptotic body formation. Scale bar: 5 μm.