Titration curve of Caspase-7 activity assay using varying amounts of Jurkat cells, untreated or etoposide-treated (6 hours). Cell extracts were prepared for immunoprecipitation using Caspase-7 Antibody. Immune complexes were incubated with peptide substrate Ac-DEVD-AFC. Specific Caspase-7 activity was measured based on the fluorescent AFC group from the hydrolysis of Ac-DEVD-AFC by activated Caspase-7. Specific inhibition assay was performed by preincubating the immune complex with Ac-DEVD-CHO for 30 minutes before adding Ac-DEVD-AFC.