As previously reported in a different setting [15], by stimulating with dendritic cells pulsed with NPM1-mutated peptides that included the 11-mer CLAVEEVSLRK peptide along with 13.9 and 14.9 epitopes, we were able to expand ex vivo leukemia-specific CD8+ and CD4+ CTLs from AML patients, as well as prime leukemia-specific responses in healthy donors. This evidence concerns the gene CD4 and acute myeloid leukemia.