(Supplementary Figure ) and PB-3 against PLY in A549 cells was illustrated by using confocal laser scanning microscopy. Mitochondria of cells were labeled with tetramethyl-rhodamine ethyl ester (TMRE) as well as with reporter substrate for the activity of capase-3/7 to monitor apoptosis induction. Cells treated with PLY only, with PLY together with PB-3 (6 µM), with PB-3 only, and untreated healthy cells were incubated for 24 h and fluorescent micrographs were recorded (Figure ). PB-3 was not only harmless to cells, rather it effectively protected cells from PLY-associated cellular damage.