Significant differences observed at this stage of ALL treatment pertained to many parameters characterizing the functional capacity of cells: lower absolute number of NKs, lower percentage of cells showing surface expression of KIR (CD158a and CD158b), as well as a lower fraction of NKs with intracellular expression of perforin and granzyme A. This evidence concerns the gene KIR2DL3 and acute lymphoblastic leukemia.