Figure 3: Assay of PMNL apoptosis developed in probes added with S. Typhimurium bacteria, after 2.5 hours of coincubation. Neutrophils were challenged with plain bacteria (Salm), opsonized with normal serum bacteria (O-Salm), and treated with sulfatides bacteria (St-Salm), as described in Section 2. We also present data of similar experiments in which zymosan—nonopsonized (Z), opsonized by normal serum (OZ) or treated with sulfatides (St-Z)—provided phagocytosable stimulus of PMNLs. Then, PS exposure of PMNL was determined using Annexin V. Shown are the mean ± SD (a) and representative spectra (b) of five independent experiments.