CD62L− T cells enhance the ability of TCD BM recipients to prevent tumor growth. T cell–depleted bone marrow cells (1 × 107) from B6 CD45.2 (A-C) or Rag1−/− or Rag2−/−γC−/− (C) mice and CD62L− T cells (1 × 106) from unprimed B6 CD45.1 mice were first transplanted into lethally irradiated BALB/c recipients. The recipient mice were then challenged with 5 × 105 host-type BCL1 tumor cells at day 7 after transplantation. The recipient mice were monitored for development of leukemia or lymphoma and survival. Each group contained 8 to 20 mice. The data are pooled from 2 independent experiments. (A) Histologic analysis of liver (H&E stain, ×100). Tissue from TCD BM only group was obtained on day 28; tissue from CD62L− T-cell recipients was obtained on day 166. (B) Survival (P < .001). (C) Survival: TCD BM only versus Rag1−/− BM only or Rag2−/−γC−/− BM only (P < .05); BM only groups versus their corresponding CD62L− groups (P < .01); TCD BM + CD62L− versus Rag1−/− BM + CD62L− or Rag2−/−γC−/− BM + CD62L− (P < .0001).