Figure 4

Spontaneous apoptosis is caspase dependent and occurs through the mitochondria. (a) Histogram plots of Annexin-V staining on monocyte subsets after 24 h culture in vitro either in the absence or in the presence of z-VAD-fmk. Data are a representative of three independent experiments. (b) Relative caspases 3 and 7 activities in monocyte subsets either freshly isolated (upper panel) or cultured in vitro for 3 or 6 h (lower panel). Data are consolidated from at least three independent experiments and error bars represent S.E.M. ^** indicates P<0.01. (c) Histogram plots of TMRM fluorescence in isolated monocyte subsets assessed at the various time points on in vitro culture. Data are representative of three independent experiments, and numbers indicate the percentage of cells that has reduced TMRM fluorescence with respect to total cells. (d) Western blot analysis of cytochrome c in the cytosolic fraction (upper panel) and mitochondrial fraction (lower panel) isolated from monocyte subsets at the various time points on in vitro culture. β-Actin and MnSOD were used as loading controls for cytosolic and mitochondrial fractions, respectively. The numbers below the blots are relative intensity values after normalizing with the respective loading controls. Data shown are representative of four independent experiments