To determine the functional effect of CD4+ T LEX-CD8086 cells on the ability to induce CD8+ T cells to anti-leukemia, DBA/2 mice were immunized with LEX-null, LEX-CD8086, CD4+ TLEX-null cells and CD4+ TLEX-CD8086 cells and with PBS, CD4+ T cells as control, and then harvested the splenic CD8+ T cells (Figure 4A). This evidence concerns the gene FUT4 and leukemia.