Electron microscopy evidence of apoptosis, autophagy, and necroptosis in obatoclax-treated primary infant ALL cells. Cases are the same as in Figure 6A-D. Molecular cytogenetic subtype and 72-hour obatoclax EC₅₀s from surviving fraction plots in Figure 1 are at left. Cells were treated for 48 hours with vehicle, obatoclax at respective 72-hour obatoclax EC₇₅ or 50 nM ADR, and harvested, stained, and sectioned for electron microscopy. Different arrowheads mark condensed chromatin of apoptosis, autophagic structures, or swollen organelles of necroptosis. Magnified insets are in boxes. Note morphologic findings indicating all 3 modes of death, including examples in single cells in all cases. Also note chromatin condensation as well as less prominent autophagic structures in ADR control cells in all cases.