FIG. 8.

The effect of pharmacological inhibitors of signal transduction pathways on the response of neutrophils to conditioned medium from infected fibroblasts (A), a mixture of G-CSF and GM-CSF (B), and medium (C). Neutrophils were preincubated with inhibitors for 1 h before and during the addition of a 1:80 final dilution of conditioned medium from infected fibroblasts, a mixture of 2 ng of G-CSF/ml and 50 pg of GM-CSF/ml, or medium. Neutrophil apoptosis was determined 18 h later by flow-cytometric analysis of staining with GFP-annexin and PI. Panel C shows the effect of inhibitors on spontaneous apoptosis (incubation with medium). Spontaneous apoptosis (neutrophils incubated with medium) is included in panels A and B for comparison. Results are reported as the means ± standard deviations of triplicate samples and are representative of three donors. Asterisk, no statistically significant difference from no-inhibitor results by a one-way analysis of variance test (P < 0.02).