Phenotype of naive and memory T cells after expansion. To examine the contribution of Treg cells and to assess the phenotype of T-cell subset cultures following expansion, T cells were analyzed for the presence of CD4⁺CD25⁺ regulatory T cells (top row), and for lymphocyte phenotype with CD4, CD8 (middle row), and CD19, CD56 (bottom row). CD62L⁺ and CD62L^– subsets are T_N and T_CM or T_EM and T_T, respectively, as shown above the diagram.