The loss of Ezh2 promotes the development of EMH. (a) Spleen weight of WT (n = 5), Ezh2^Δ/Δ (n = 5), JAK2^V617F (n = 5), and JAK2^V617F/Ezh2^Δ/Δ (n = 9) mice 4 wk after the deletion of Ezh2. (b) Proportions of Gr-1⁺ and/or Mac-1⁺ myeloid, B220⁺ B cells, CD4⁺ or CD8⁺ T cells, and Ter119⁺ erythroid cells among CD45⁺ hematopoietic cells in the spleen. (c) Histology of the spleen from WT, Ezh2^Δ/Δ, JAK2^V617F, and JAK2^V617F/Ezh2^Δ/Δ mice observed by hematoxylin-eosin staining (top) and silver staining (bottom). Bars, 50 µm. (d) Proportions of LSKs and MkPs (Lin⁻Sca-1⁻c-Kit⁺CD150⁺CD41⁺) in the spleen of WT, Ezh2^Δ/Δ, JAK2^V617F, and JAK2^V617F/Ezh2^Δ/Δ mice (n = 5–9) 4 wk after the deletion of Ezh2. (a, b, and d) Bars and asterisks show the mean ± SEM and *, P < 0.05; **, P < 0.01; and ***, P < 0.001 by the Student’s t test; two independent experiments.