To detect CD3+cells, slides were steam hydrated and pretreated with Diva Solution (Biocare Medical Concord, CA) for 20 minutes. The primary antibody, rabbit antihuman CD3, (A-0452, Dako Corporation, Carpentaria, CA) was used at a dilution of 1:300. The detection system was the Standard ABC kit (Vector Laboratories, Burlingame, CA), with 3,3'-diaminobenzidine (DAB) as the chromogen and a modified Harris hematoxylin counterstain.