Later, Miller and colleagues showed that infusion of haploidentical, related donor NK cells in AML patients induced complete hematologic remission in 5 of 9 poor prognosis patients, after pretreatment with high-dose cyclophosphamide and fludarabine (Hi-Cy/Flu) and in the presence of interleukin (IL)-2 [18]. The gene discussed is IL2; the disease is acute myeloid leukemia.