CD4 and leukemia: To address whether LEX-CD8086 targeted-activated CD4+ T cells (CD4+ TLEX-CD8086) can induce stronger anti-leukemic immune effects, we examined their anti-leukemia immunity in vitro and vivo. An in vitro study uncovered that the CD8+ T cells from the CD4+ TLEX-CD8086 cell immunized mice differentiated more frequently into CTL effectors and specifically induced more L1210 cell apoptosis than the LEX-CD8086 immunized mice did.