Antigen-expressing DC inactivate CD8⁺ effector T cells. CD45.1⁺ OT-I effector/memory cells were transferred intravenously to 11c.OVA or nontransgenic (non-tg) recipients and (A-D) spleen cells were recovered 3, 7, 14, 28, or 42 days later. (A) IFN-γ production in response to OVA_257–264 and (B) the total number of IFN-γ–producing OT-I cells per spleen was determined by ICS. (C) OT-I degranulation in vitro was determined at selected time points after transfer. Numbers on plots are the precentages of cells in each gate for that plot. (D) Killing of CFSE-labeled OVA_257–264-pulsed targets was determined at selected time points after OT-I effector/memory transfer. *11c.OVA is significantly less than non-tg (P < .05). (E) TCR Vα2 levels on splenic OT-I cells (CD45.1⁺/CD8⁺) were determined by flow cytometry at selected time points after transfer. Data are either (A,C,E) representative of at least 2 mice in at least 2 independent experiments at each time point (B,D) or pooled (mean ± SD) from 2 independent experiments using 2 mice per group at each time point.