Dasatinib induces an increased number of mature MKs in BM and spleen. (A) Representative longitudinal sections of whole murine femurs and spleens stained with H&E from control mice and dasatinib-treated (5 mg/kg/d) mice for 7 days (scale bar = 50 μm). (B) Representative longitudinal sections of whole murine femurs from control mice compared with dasatinib-treated (5 mg/kg/d) mice that are undepleted versus platelet depleted after immune-induced thrombocytopenia by anti-GPIbα antibody (2 μg/g body weight) at various time points. MKs were identified by anti-mouse GPIIb-FITC antibody (scale bar = 20 μm). (C) Quantification of the number of MKs in the BM from control and dasatinib treated-mice that are undepleted versus platelet depleted. The average number of MKs per field was determined in GPIIb-stained BM sections throughout the length of 3 femurs; ***P < .005.