A. Determination of the IC50 of MLT. B. Apoptotic cells were detected using TUNEL assay. Histograms represent the percentage of Tunel positive cells (yellow) and Tunel negative cells (green). LD WT, LD AQP EOEs, LD AQP KO, LD AQP AB, and LD PAPO-I KO cells were treated with 5 and 10 μM MLT. DNase treated cells were used as positive control. Three experiments were performed, and 200 cells were counted by experiment. Statistically significant p < 0.005 (*p < 0.05; ***p < 0.0005; ****p < 0.0001) are indicated.