Xenogeneic Adoptive Transfer Model

The xenogeneic adoptive transfer model was performed as we have previously described (10 (link)). NOD-scid IL2Rgamma^null (NSG) mice (stock number is 005557 from Jackson Laboratory, Bar Harbor, ME) were housed in a specific pathogen-free facility. Weight matched (26-30g) female mice were subjected to whole-body preconditioning irradiation (225 cGy using an X RAD 320, Precision X-ray, North Branford, CT, USA) for consistent NK cell engraftment. Freshly, enriched human NK cells underwent initial overnight incubation in B0 media [DMEM, Ham’s F12 with 10% human AB serum, Pen/Strep (1%), 2-ME (20 μm), ethanolamine (50 μm), ascorbic Acid (10 μg/ml) and sodium selenite (1.6 ng/ml)] containing 2.5 ng/ml rhIL-15 (NCI), and 4x10⁶ cells were injected via tail vein in each mouse. Mice were also administered rhIL-15 (NCI) ip at dose of 5 μg. The indicated mAbs were ip administered at a dose of 10 mg/kg. A schematic of the treatment schema is provided in Figure 2A. Blood was collected via retro-orbital route in heparin. Absolute counting of human NK cells in the peripheral blood was performed on a flow cytometer using a bead counting method (AccuCheck, Thermo Scientific, Waltham, MA, USA) according to the manufacturer’s instructions.