PRF1 and acute lymphoblastic leukemia: In line with fewer eliminated cell clones, we detected more static B-ALL clones upon co-culture with Prf1-/- or Ifng-/- NK cells (B-ALL+Prf1-/- NK cells n=420 vs B-ALL+WT NK cells n=190; B-ALL+Ifng-/- NK cells n=281 vs B-ALL+WT NK cells n=102).