Cell differentiation and blast clearance in P/R and P/R-FLT3ki APL on ATRA treatment. (A) ATRA-induced differentiation of P/R (top) and P/R-FLT3ki (bottom) bone marrow cells, as assessed by MGG staining (scale bar, 10 µm). FACS analysis after 2, 6, and 12 days of in vivo ATRA treatment. GFP-positive leukemic cells (pink) and GFP-negative normal cells (blue) are shown. (B) Percentages of GFP-positive APL cells in bone marrow of untreated (UT) and ATRA-treated P/R (red bars) and P/R-FLT3ki (blue bars) mice at 2 to 12 days posttreatment. Data are expressed as mean ± standard deviation of 2 independent experiments. (C) Survival of secondary recipients transplanted with total APL bone marrow cells from ATRA 6-day-treated primary APL mice in both models (n ≥ 10 for each model).