Apoptosis in the liver and spleen following siRNA treatment. (A) Representative immunofluorescent micrographs indicating TUNEL-positive cells in liver sections after CLP; (i) saline treatment, (ii) GFP siRNA, and (iii) Fas siRNA. (B) Apoptotic index of hepatocytes and splenocytes following caspase-8 and Fas siRNA treatment following CLP as determined by TUNEL. ▪ indicates hepatocytes; □, splenocytes. ^*#P < .005 versus saline and GFP controls, Mann-Whitney U test (n = 5/group). (C) Apoptotic index in the thymus following caspase-8 or Fas siRNA treatment following CLP. Data are presented as mean ± standard error (SE) of the mean.