Granzyme B is a major cytotoxic T lymphocyte/natural killer (CTL/NK) granule protease that
can activate members of the caspase family of cysteine proteases through processing of
caspase zymogens. However, the molecular order and relative importance of caspase
activation events that occur in target cells during granzyme B-initiated apoptosis has not
been established. Here, we have examined the hierarchy of granzyme B-initiated caspase
activation events using a cell-free system where all caspases are present at physiological …