Alloreactivity of freshly isolated naive and memory T cells. To measure the alloreactivity of uncultured naive and memory T cells, fresh PBMCs were sorted into CD62L⁺CD45RA⁺ (T_N), CD62L⁺CD45RA^– (T_CM), CD62L^–CD45RA^– (T_EM), or CD62L^–CD45RA⁺ (T_T) subsets (A) or CD4⁺CD62L⁺, CD4⁺CD62L^–, CD8⁺CD62L⁺, or CD8⁺CD62L^– (B) and measured for proliferation against 2 separate allogeneic LCLs. Data shown here are the mean values for each donor (n = 5) and stimulator (n = 2) pair done in triplicate. Error bars indicate statistical analyses performed between groups.