Anti–IL-2Rα mAb blockade does not prevent the vaccine-induced expansion of antigen-specific CD8⁺ T cells. CMV-pp65–specific CD8⁺ T cells were determined by flow cytometric analysis of PBMCs both before (pre) and 43 to 55 days after (post) administration of CMV-pp65 DC vaccine and daclizumab. (A) Data are shown as the average fold increase (post/pre) in the frequency of pp65⁺CD8⁺ T cells from 4 REGULATE patients (individual patient average of tetramer⁺CD8⁺ T cells across tested HLA alleles). (B) Representative FACS plot of pp65-tetramer⁺CD8⁺ T cells. Gating strategy: total lymphocytes selected from forward scatter and side scatter display, CD3⁺CD8⁺ T cells selected from total lymphocytes, and pp65⁺ T cells selected from total CD3⁺CD8⁺ population (supplemental Figure 12).