T-cell subset cell sorting and phenotype following expansion. Fresh PBMCs were labeled with CD62L FITC and CD45RA PE (A) and sorted by flow cytometry into CD62L⁺CD45RA⁺ (T_N), CD62L⁺CD45RA^– (T_CM), CD62L^–CD45RA^– (T_EM), or CD62L^–CD45RA⁺ (T_T) T-cell subsets (B, first column). Following isolation, T cells were stimulated with OKT3 in the presence of IL-2 and expanded for 21 days in which the phenotype of CD62L and CD45RA was monitored (B). The percentage of events in each quadrant is indicated.