Used in immunotherapy research targeting CD123-expressing hematological malignancies such as acute myeloid leukemia (AML) and blastic plasmacytoid dendritic cell neoplasm (BPDCN). Serves as a critical reagent for developing and validating anti-CD123 therapeutic antibodies, CAR-T cells, and bispecific engagers. Employed in binding assays, structural studies, and immunoassay standardization due to its functional epitope presentation. The His tag facilitates easy detection and purification in experimental workflows.