MSCs protect CML LSCs capable of engrafting NSG mice from TKI treatment. CML CD34+ cells (2 × 106 cells per mouse) from 3 patients were cultured for 96 hours with and without MSCs and with or without IM and transplanted into NSG mice. Mice were euthanized after 4 and 10 weeks, and marrow contents of femurs, spleen cells, and blood cells were obtained. (A) Flow cytometry plots and (B) graphs showing human cell engraftment in peripheral blood (PB), BM, and spleen at 4 weeks (4w) posttransplantation. (C) BCR-ABL mRNA levels in marrow cells obtained from mice at 4 weeks posttransplantation. (D) Flow cytometry plots and (E) graphs showing human cell engraftment in PB, BM, and spleen at 10 weeks posttransplantation. (F) BCR-ABL mRNA levels in marrow cells obtained from mice at 10 weeks (10w) posttransplantation. ns, not significant. n = 5. *P < .05; ***P < .001.
