DZNep preserves CD4⁺ T cell-mediated GVL while inhibiting GVHD. (A-D) Lethally irradiated BALB/C recipients were transplanted with donor B6 TCD BM, with or without CD4⁺ T_N cells, and challenged with or without A20^TGL cells (1 × 10⁶/mouse). Twelve doses of DZNep were administered from day 0 to day 27 after transplantation (A-C) or from day 7 to day 29 after transplantation (B,D). The survival was monitored over time (A,C-D). In vivo detection of luciferase activity at days 14, 28, and 42 after transplantation (B). (E) Donor T cells were isolated from the spleen at day 14 for CTL assay against A20 cells.