There was no correlation of HLA I expression and NK cell mediated cytolysis of childhood AML blasts independent from E : T ratio and without or with IL2 prestimulation (n = 14, donors A and B, E : T 10 : 1, without IL2, Pearson r = −0.06, p = 0.83; with IL2, r = −0.11, p = 0.70) (Figures 2(a) and 2(c)). This evidence concerns the gene IL2 and acute myeloid leukemia.