Fig. 3.
Change in the status of PARP, but not IκBα, attributable to caspase activity in HL-60 cells undergoing PDT-induced apoptosis.
Cells were incubated with verteporfin (100 ng/mL) for 60 minutes at 37°C and then were kept in the dark or were irradiated with red light (2 J/cm2). The general caspase inhibitor ZVAD.fmk (100 μmol/L) was added 30 minutes before light irradiation. Cell lysates were prepared 60 minutes after irradiation and were subjected to Western immunoblot analysis with antibodies against caspase-3, caspase-9, PARP, and IκBα. The rabbit anti-IκBα polyclonal antibody was raised against residues 27-38 of the molecule. Molecular sizes of caspase-3, caspase-9, and PARP fragments are indicated.
