GVL effects of delayed DLI. (A) B10.A → B6 FCs received 3 × 10⁷ B10.A DLI alone (▴, n = 7) on day 56 after BMT, C1498 myeloid leukemia cells (5 × 10⁴) alone (*, n = 8) on day 63, or both (□, n = 8). (B) In the same experiment, B10.A + B6 → B6 MCs received DLI alone (•, n = 6) on day 56, C1498 cells alone (○, n = 7) on day 63, or both (▾, n = 7). MCs receiving DLI and C1498 (▾, n = 7) showed markedly improved survival compared with FCs receiving DLI and C1498 (panel A: □, n = 8; P < .01). (C) C3.SW → B6 FCs received 1 × 10³ EL4 cells (*, n = 7) on day 63 or 3 × 10⁷ C3.SW SCs as DLI on day 56 after BMT plus 1 × 10³ EL4 on day 63 (□, n = 11). (D) C3.SW + B6 → B6 MCs also received EL4 cells alone (○, n = 7) on day 63, or both DLI and EL4 cells (▾, n = 10). MCs receiving DLI and EL4 showed similar survival compared with full chimeras receiving DLI and EL4.