Figure 4

Daratumumab interferes in AML cell trafficking. (A) Schematic illustration of in vivo treatment protocol with ATRA (10 mg/kg) for all mice and daratumumab/IgG₁ (8 mg/kg) after engraftment of primary human AML cells in NSG mice. (B) Representative flow cytometry plots of human hematopoietic engraftment by gating on human CD45⁺ cells in bone marrow, peripheral blood and spleen of mice treated with daratumumab or IgG₁ control. (C) Quantification of human AML engraftment (CD45⁺/CD33⁺ cells) in peripheral blood, bone marrow and spleen. Every dot represents mean of all mice per AML sample, n = 5 different primary AML samples and n = 1-5 mice per sample per group. (D) White blood cells count, hemoglobin levels, platelet count, wet spleen weight and cells per femur of daratumumab or IgG₁ treated mice (data normalized to control, n = 26). (E) Schematic illustration of treatment protocol with cytarabine (20 mg/kg), ATRA (10 mg/kg) and daratumumab/IgG₁ (8 mg/kg) after engraftment of primary human AML cells in NSG mice. (F) Quantification of human AML engraftment (CD45⁺/CD33⁺ cells) in peripheral blood, bone marrow and spleen. Every dot represents mean of all mice per AML sample, n = 2 different AML samples, 2–3 mice per sample per group. (H) Top, experimental layout to test for interference in AML homing. Below, human AML engraftment (CD45⁺/CD33⁺ cells) in bone marrow (BM), peripheral blood (PB) and spleen 16 h after transplantation, n = 5 mice per group, 2 different AML samples. Right, representative flow cytometry plots of human hematopoietic engraftment by gating on human CD45⁺ cells in bone marrow, peripheral blood and spleen for each experimental condition. (H) Quantification of transendothelial migration of primary AML cells (n = 4, mean of duplicates). Shown is migration index calculated by cells migrated/total cells seeded, normalized to IgG₁ control (each dot represents the mean of triplicates). Data are shown as mean ± SEM. n.s., not significant, *p < 0.05, **p < 0.01 as determined by Wilcoxon signed-rank test (C), paired students t-test (D, G) and Mann–Whitney-U Test (F, H). See also Supplementary Fig. S6.