Figure 9. Reduction in RBC mass leads to the amelioration of vascular occlusion with loss of Plek2.

(A) JAK2^V617F-knockin mice were chronically injected with Ly-6G antibody at 5 mg/kg every 3 days for 6 months. Absolute neutrophil count and RBC count in the IgG control– and Ly-6G–injected mice 2 months after injection is presented. N = 8/group. Both males and females were included in each group. K, thousands; M, millions. (B) Kaplan-Meier survival analysis of A. BMT, bone marrow transplantation. (C) Histologic examination of the lungs of the indicated mice. The histologic images are representative of 5 mice in each group analyzed. (D) Quantification of the number of vascular occlusions (>50 μm in diameter per ×4 field) in the lungs from the indicated mice. Fifteen fields were analyzed from 5 mice in each group. (E–H) Same as A–D except that the mice were chronically injected with PHZ at 25 mg/kg every 3 days for 6 months. N = 8/group. (I) Wild-type or Plek2-knockout mice were chronically injected with erythropoietin at 5,000 U/kg every 2 days for 3 weeks. RBC counts were analyzed 3 weeks after injection. N = 6/group. (J) Spleen weight of the mice from I. (K) Histologic examination of the lungs of the indicated mice. The histologic images are representative of 5 mice in each group analyzed. (L) Quantification of the number of vascular occlusions as in D. *P < 0.05 and ****P < 0.0001, by 1-way ANOVA with Tukey’s multiple comparisons test. All scale bars: 100 μm.