The anti-leukemia activity of unmodified NK-92 cells, NK-92 cells modified with an alpharetroviral vector to express only the EGFP marker as a control, Δ-CAR-NK-92 cells, and CAR-NK-92 cells against the CD123+ AML cell line KG-1a was compared in co-culture experiments. Here, IL3RA is linked to leukemia.