Impaired megakaryocyte development and proplatelet formation. (A) Mature bone marrow-derived megakaryocytes from Shp1 KO, Shp2 KO, Shp1/2 DKO, and litter-matched WT (Shp1 WT, Shp2 WT, and Shp1/2 WT) mice were stained with propidium iodide and ploidy of cells was quantified by flow cytometry. Representative profiles of n = 4-6 mice/genotype. (B) The percentage of 2-4N and 8-128N ploidy cells was quantified (n = 4-6 mice/genotype; mean ± SEM; **P < .01, ***P < .001). (C-F) Mature bone marrow-derived megakaryocytes from Shp1 KO, Shp2 KO, and corresponding litter-matched WT mice were platelet on fibrinogen-, fibronectin-, and collagen-coated surfaces. (C-D) Representative images of spread megakaryocytes (Alexa Fluor 488-phalloidin stained) and (E-F) megakaryocytes undergoing proplatelet formation (FITC-αIIb stained; n = 4-6 mice/genotype). (C-D) Megakaryocyte surface area, (E-F) proplatelet surface area, and percentage of megakaryocytes undergoing proplatelet formation (n = 4-6 mice/genotype; mean ± SEM; ***P < .001; bar represents 20 μm).