Effect of dn-Survivin on development of acute leukemia induced by ITD-Flt3. (A) Ba/F3 cells expressing MSCV wild-type or ITD-Flt3 were retrovirally transduced with MIEG3 vector or dn-mouse T34A Survivin in MIEG3, as described.³¹  Three million Ba/F3 cells expressing wild-type or ITD-Flt3 plus MIEG3 vector or dn-T34A Survivin were injected into BALB/c mice (Harlan) as described.¹²  Kaplan-Meier survival curve for BALB/c mice that received a transplant of 3 × 10⁶ Ba/F3 cells expressing human wild-type (WT) Flt3, ITD-Flt3 (N73), or ITD-Flt3 plus dn-T34A mouse Survivin. *P < .05 compared with ITD-Flt3 alone. N = 10 mice/group. (B) Representative histology of bone marrow from recipients of control, ITD-Flt3 cells, or ITD-Flt3 plus dn-T34A-Survivin–transduced Ba/F3 cells. Infiltration of blasts and lack of megakaryocytes are observed in the bone marrow of recipients of transplanted ITD-Flt3–transduced Ba/F3 cells, whereas the nuclear fragmentation and cell maturation of the myeloid cells were significantly improved in the recipient mice of transplanted Ba/F3 cells overexpressing ITD-Flt3 plus dn-T34A Survivin. The image was taken using a BX60 microscope UPlanF1, DP 71 camera, and DP Controller software (Olympus, Melville, NY). Original magnification: 40 ×. Size: 100 × 100 μm². Scale: 20 μm for all photographs.Numeric aperture 0.75. Total magnification is expressed as the objective times the eyepiece: 40 (objective)×10 (eyepiece) =400 (total). Staining: Giemsa.