Novel mouse model of PV. (A) Schematic of BM transplant PV mouse model. (B-G) RBCs (B), reticulocytes (C), HCT (D), HGB (E), MCH (F), and MCV (G); control, n = 24 control and PV, n = 25. (H) Kidney Epo mRNA expression relative to Hprt; n = 6. (I) Spleen weight normalized to total body weight; n = 24. (J) Terminal erythropoiesis in the BM determined by flow cytometry. Based on CD44 expression and FSC-A, Ter119⁺ cells were gated into 5 distinct populations: I, proerythroblast (Pro-E); II, basophilic erythroblasts (Baso); III, polychromatic erythroblasts (Poly); IV, orthochromatic erythroblasts and reticulocytes (Ortho/Retic); and V, RBCs. Control, n = 24 control and PV, n = 25. Erfe mRNA expression relative to Hprt in (K) the BM, n = 13 control; PV, n = 17, and (L) the spleen; control, n = 7; PV, n = 14. (M) Serum ERFE; control, n = 14; PV, n = 15. (N) Liver Hamp1 mRNA expression relative to Hprt; control, n = 13; PV, n = 17. (O) Serum hepcidin; control, n = 9 and PV, n = 12. (P) Serum iron; n = 6. (Q) Liver; control, n = 17 and PV, n = 21. (R) Spleen (n = 15) nonheme iron content. Mann-Whitney test for panels B,D,I,L,M,N, unpaired 2-tailed t test with Welch correction for panels C,E-H,K,O-R, or two-way analysis of variance (ANOVA) with Šídák correction for multiple comparisons for panel J. ∗∗P < .01; ∗∗∗P < .001; and ∗∗∗∗P<.0001.