NKG2D-mediated lysis of leukemic cells. PBMCs of patients were tested for recognition by NKL cells in a 5-hour chromium release assay. NKG2D-dependent killing was scrutinized by preincubation of UPN 5 PBMCs with anti-MICA mAb AMO1 (▴) or IgG1 isotype control antibodies (▵; A), or NKL cells with anti-NKG2D mAb 8G7C10 (▪) or IgG2a isotype control antibodies (□; B). PBMCs of UPN 4, UPN 12, UPN 20, and UPN 23 were preincubated with anti-MICA mAb AMO1 (▴) or IgG1 isotype control antibodies (▵) and assayed with NKL cells (C).