CD4 and leukemia: DC-loaded with DNR-treated AML cells were more efficient than DC-loaded with ARA-C-treated cells not only, as expected, in inducing leukemia-reactive CD8+ T cells (Figure 2A), but also in increasing the frequency of CD4+CD25+Foxp3+ T cells (11.70 ± 4.15 versus 5.97 ± 3.10%, respectively; p < 0.05) (Figure 2B).