Fig. 1.
zVAD attenuates anti-Fas antibody–induced neutrophil cell death but paradoxically augments TNF-α–induced neutrophil cell death.
One million freshly isolated mature human neutrophils (5 × 106 cells per milliliter) were preincubated with or without the cell-permeable, broad-spectrum caspase inhibitor zVAD (100 μM) for 1 hour. Subsequently, at time 0, neutrophils were stimulated with TNF-α (10 ng/mL), anti-Fas antibody (CH-11; 100 ng/mL), or an equivalent volume of buffered saline. The total number of viable neutrophils that remained, as defined by trypan blue dye exclusion, was determined with a hemacytometer at indicated times. Data shown are means ± SEM and are representative of 3 experiments performed in triplicates. *P < .05 compared with no zVAD at the corresponding time point.