Aberrant megakaryocyte counts and myelofibrosis in DKO and TKO mice. Histological sections of mouse bone marrow (A), spleen (B), and lung (C) of the indicated genotypes stained with hematoxylin and eosin (H&E), the megakaryocytic marker CD42b, or reticulin. MKs are highlighted by yellow arrows. (D) Total number of MKs per section in the indicated organs, n = 5 mice/genotype. (E) MK numbers per field of view in the indicated organs, n = 5 mice/genotype (mean of 15 fields/mouse). Analysis of MK numbers was performed in a double-blinded manner. *P < .05, **P < .01, ***P < .001, 1-way ANOVA with Sidak test; mean ± SD.