Increased numbers of megakaryocyte-committed cells in the HSC compartment of Cul5^fl/flVavCre mice. (A) Numbers of megakaryocyte colonies and other myeloid colonies cultured from whole BM (per 25 000 cells, n = 3) and sorted BM populations (per 500 cells, n = 3-4) as shown (LSK [Lin⁻Sca1⁺Kit⁺], HSC [Lin⁻Sca1⁺Kit⁺CD150⁺CD48⁻; CD41⁺HSC, CD41^loHSC], MPP [Lin⁻Sca1⁺Kit⁺CD150⁻CD48^lo/−], HPC1 [Lin⁻Sca1⁺Kit⁺CD150⁻CD48⁺], HPC2 [Lin⁻Sca1⁺Kit⁺CD150⁺CD48⁺]). (B) Differential counts (per 500 cells) of colony types in cultures of LSK cells from Cul5^fl/flVavCre and control Cul5^fl/fl mice (n = 7). Cells were plated in semisolid agar cultures containing stem cell factor, IL-3 and EPO, and incubated for 7 days before fixation, staining, and counting. (C) Numbers per femur (left panel) and percentage in the HSC population (right panel) of CD41⁺HSC (Lin⁻Sca1⁺Kit⁺CD150⁺CD48⁻CD41⁺, n = 6-8). The fold-difference in numbers of CD41⁺HSC between Cul5^fl/flVavCre and Cul5^fl/fl mice is indicated above the bar graph. (D) Expression profiles (left panel), median VWF signal intensity (center panel) of VWF expression measured by mass cytometry and proportion of VWF⁺ cells in HSC (right panel, Lin⁻Sca⁺Kit⁺CD150⁺CD48⁻) from Cul5^fl/flVavCre and Cul5^{+/+ or fl/fl} mice (n = 3). Each point represents data from an individual mouse, bars represent mean ± SD. ∗P < .05, ∗∗P < .01, ∗∗∗P < .001 for comparison of data from Cul5^fl/flVavCre with Cul5^{+/+ or fl/fl} mice (unpaired Welch t test with Holm-Sidak correction for multiple comparisons). Eo, eosinophil; Ery, erythroid; G, granulocyte; GM, granulocyte-macrophage; M, macrophage; Meg, megakaryocyte; Meg/E, megakaryocyte/erythroid; mixed, mix of 3 or more colony types and blast cell colonies.