Figure 1

In vitro morphology of NB cells cultured with or without CHS 828. IMR-32 (1.5 × 10⁵/ml) were cultured in 24-well plates in the absence (control) or presence of 1 nM CHS 828 for 0 to 72 h. Cell morphology, investigated by phase-contrast microscopy, revealed signs of cell death in NB cells exposed to CHS 828 (A). Viability of NB cells (IMR-32) was quantified in DAPI (4',6-diamino-2-phenylindole)-propidium iodine (10 μg/ml)-stained cells by fluorescence microscopy (B). Cells with intact plasma membrane (blue; DAPI staining) and cells with disrupted membrane (red; propidium iodine staining), magnification in A-B: × 100.