Analysis of CEA-specific T cells by ELISPOT assay for each cohort.PBMCs collected before and after TRICOM-CEA vaccination were analyzed for their response to rF-CEA(6D)-TRICOM by ELISPOT assay. The data represent the mean number of IFNγ-producing cells per 100 000 PBMCs plus or minus SE for patients completing 4 injections for each cohort. Arrows indicate time of denileukin diftitox administration.