PKR, RIG1 and HMGB1 protein in post-transplant kidneys. The protein expression of PKR, RIG1 and HMGB1 detected by western blotting (A-C) was significantly increased in the caspase-3 siRNA preserved post-transplant kidneys (D and F). There was no significant difference in RIG1 between the two groups (E). The data are expressed as corrected volume density against the loading control of 42 kD β-actin. Mean ± SEM, n = 5. *: P < 0.05; **: P < 0.01.