5.6.1. Sample preparation for measuring caspase activation by
immunoblotting
Cell lysates are made as described in Section 5.2. After adding
0.2 volume of 5 Laemmli buffer, boil the sample for 5–10 min.
Laemmli buffer 5 contains 312.5 mM Tris–HCl, pH 6.8, 10% SDS,
50% glycerol and 20% b-mercapto-ethanol. Equal volumes are
loaded on 12.5% SDS–polyacrylamide gels, and after separation
the proteins are transferred to a nitrocellulose membrane. The different
caspases are detected with the appropriate antibodies. The
signal is revealed with, e.g. Chemiluminescence Reagent Plus
(PerkinElmer Life Sciences, Boston, USA).