Figure 2 Analysis by flow cytometry of apoptotic HeLa cells stained with FITC-Dextran and PI. Apoptosis was induced by incubating the cells at 43.5°C for 1 hour and at 37°C for 8 hours. Then the cells were labeled with PI or FITC-Dextran. The results are typical of those seen with the 16 different samples, each tested twice