α-GalCer–loaded AML-ETO9a tumor cells is effective at suppressing leukemic tumor growth in both prophylactic and therapeutic vaccine settings. (A) WT mice (n = 5 per group) were challenged intravenously with 1 × 106 unloaded or α-GalCer–loaded AML-ETO9a GFP/luciferase-expressing tumors. (B) WT mice (n = 5 per group) were challenged with 1 × 106 AML-ETO9a tumor cells, and 2 weeks later some were treated with single administration of irradiated, α-GalCer–loaded autologous AML-ETO9a tumor cells (indicated by arrow). (A-B) Representative in vivo bioluminescent images of tumor (luciferase activity at 5 weeks) and corresponding quantification of tumor burden (bioluminescent photon counts; middle graphs) over time. Survival curves are shown to the right. Date are mean ± SEM. **P < .007 (unpaired t test, or log-rank test for survival). *P < .05 (unpaired t test, or log-rank test for survival). ns indicates not significant. Two independent experiments were performed.