Treatment schema for clinical trial combining salvage chemotherapy, DLI, and ML NK cell infusion. Patients provided consent and were enrolled in clinical trial NCT03068819. Salvage chemotherapy with fludarabine, cytarabine, and granulocyte colony stimulating factor was administered 2 to 4 weeks before ML NK cell infusion. On day −1, a nonmobilized leukapheresis product was collected from the same donor as HCT. T-cell DLI (1 × 10⁶ T cells per kg) was immediately infused into the patient. The remainder of the apheresis product was enriched for NK cells, which were then stimulated overnight with IL-12, L-15, and -18 to generate ML NK cells, which were infused into the patient the next day (day 0; max dose, 10 × 10⁶ cells per kg). Disease assessment (clinical response) and adverse events were subsequently monitored, and samples for were collected for correlative experiments. SOC, standard of care.