FIGURE 7.

Apoptotic targets induced by chemical anoxia decrease viability of BU.MPT responder cells. Serum-starved BU.MPT responder cells were exposed to apoptotic (Apo) targets at a target/responder cell ratio of 10:1 continuously for 24 h. The source of apoptotic targets was DO11.10 cells treated with actinomycin D (Act D); 2-deoxyglucose (DOG) (500 μm) plus 0 mm dextrose; or antimycin A (Antimyc A) (2 μm) plus 5, 10, or 25 mm dextrose (Dex). For targets induced by chemical anoxia, the apoptotic process was terminated by paraformaldehyde fixation at 6 or 24 h following initiation of the apoptotic stimulus, as depicted in the inset. For targets induced by actinomycin D, the apoptotic process was terminated only at 24 h. Relative cell number of responders was determined by MTT assay at 48 h following exposure to targets. A_570/650 values were normalized against those for BU.MPT responder cells not exposed to targets as represented by the dotted line at relative cell number equal to 1.0. Each data point in the graphs represents the mean and S.E. from a minimum of three or more separate experiments. The absolute A_570/650 for control responders unexposed to targets was 0.481 ± 0.017. All experimental A_570/650 values were normalized to these values. p < 0.0001, apoptotic targets versus no targets for all apoptotic stimuli and times of fixation after induction of apoptosis. Error bars denote S.E.