Antitumor effect of DLI and RLI against a myeloid leukemia, MMB3.19. (A) Mean (± SEM) B-cell chimerism at various times in control mixed chimeras (□; n = 7) and chimeras receiving recipient leukocyte infusion (RLI) (▵;n = 7) and donor lymphocyte infusion (DLI) (○; n = 9) on day 35. Similar results were seen for all WBC lineages examined (T cells, granulocytes, monocytes). (B) Mixed chimeras received MMB3.19 at a dose of 1 × 10⁶ intraperitoneally on day 42 with no additional treatment (▪; n = 9) or 1 week following DLI (3 × 10⁷ B10.A spleen cells intravenously) on day 35 (*; n = 7). (C) Mixed chimeras received MMB3.19 at a dose of 1 × 10⁶ cells intraperitoneally on day 42 with no additional treatment (▪; n = 9) or 1 week following RLI (3 × 10⁷ B6 spleen cells intravenously) (•; n = 7). (D) Survival of conditioned, non-BMT control mice that received RLI (3 × 10⁷ B6 splenocytes intravenously) on day 35 and MMB3.19 (1 × 10⁶ cells) on day 42 after BMT (▿; n = 6) is compared with that of simultaneously prepared mixed allogeneic chimeras also receiving MMB3.19, with (○;n = 7) or without (*;n = 6) RLI.