Regeneration of alloreactive NK-cell repertoires against a KIR-ligand–mismatched target. (A-B) Immunophenotype of NK-cell repertoire in donors and recipients after Treg (A) and standard (B) HLA-haploidentical transplantation identified potentially alloreactive NK cells expressing single KIR. KIR2DL2/3 P < .01 at 1, 3, and 5 months. (C-D) Cytotoxicity assay identified alloreactive NK cells that killed KIR ligand–mismatched PHA lymphoblasts in donors and recipients after Treg (C) and standard (D) HLA-haploidentical transplantation (P = NS).