Figure 3

Depolarization causes larger relative increases in annexin V binding at lower calcium concentrations. Jurkat cells were treated with UV light, then assayed by flow cytometry 3.5 h later. Cells were assayed with Alexa-680-annexin V-117 in either Buffer A or Buffer B with the indicated concentration of calcium chloride. The subpopulation of small apoptotic cells was selected with a forward-scatter gate as shown in Figure 2C, and the mean annexin V fluorescence of this population was calculated. The graph shows the ratio of mean annexin V fluorescence in depolarizing buffer to mean annexin V fluorescence in non-depolarizing buffer at each calcium concentration.