BMNs were treated with matrine (0, 0.1, and 1.0 mM) with/without CSE for 24 h, followed by Annexin V and PI staining. (A) A representative flow cytometric plot of Annexin V and PI staining of a single sample from each treatment group. The percentages of neutrophils in each quadrant are shown. Live cells were considered to be Annexin V− PI−, early apoptotic cells were Annexin V+ PI−, late stage apoptotic cells were Annexin V+ PI+ and necrotic cells were considered to be Annexin V− PI+. (B) Graph of pooled data of the different stages of cell death and total (early + late) apoptotic cells. Data are expressed as mean ± S.E.M. for n=3–4 per treatment group from three to four separate experiments. Two-way ANOVA with Sidak test was performed. P-value represents **P<0.01, ***P<0.001, ^##P<0.01; ^###P<0.001, ^####P<0.001.