Tagraxofusp treatment results in significant reduction of leukemic blasts and pDCs in vivo. (A-C) BM cells harvested from primary NSG mice were injected IV into secondary NSG mice. The mice were treated by intraperitoneal injection for 1 cycle with PBS, tagraxofusp 0.1 mg/kg per day, or 0.2 mg/kg per day. (A) One week after the last dose, hCD45⁺ cells were examined in peripheral blood. (B) Leukemic blasts and pDC proportions are shown in hCD45⁺ compartments. (C) CD34⁺ leukemic blast proportions in total white blood cells (WBC) were also evaluated. Data are mean ± SD. (D-F) Representative flow plots show leukemic blasts and pDCs after treatment with PBS (D), tagraxofusp 0.1 mg/kg per day (E), or tagraxofusp 0.2 mg/kg per day (F). (G) BM cells were harvested from mice treated with PBS or tagraxofusp 0.1 mg/kg per day. CD34⁺ leukemic blasts and pDCs were enumerated. **P < .01, ***P < .001.