A, Western blot analysis of splenocytes from vehicle/ruxolitinib-treated MPLW515L diseased mice. B–D Deletion of Stat3 prolongs survival (B, n=8) and reduces organomegaly (C) and leukocytosis (D) in the MPLW515L BMT model compared to control mice. Mean ± s.e.m. of two independent experiments. E, Peripheral blood flow cytometric analysis. F, Reduced bone marrow cellularity and reticulin fibrosis in the bone marrow of MPLW515L-expressing Stat3fl/fl;Vav-Cre+ and MPLW515L-expressing Stat3fl/fl;Vav-Cre− mice. Representative pictures of three independent experiments. 20x magnification. G, Number of GFP-positive MEP cells is decreased in the bone marrow of mice transplanted with MPLW515L-expressing Stat3-deleted bone marrow compared to MPLW515L-diseased controls. Mean ± s.e.m. of two independent experiments. Vav-Cre+: n=16, Vav-Cre−: n=10. H,
Stat3 deletion reduces serum cytokines in MPLW515L-transplanted recipient mice. Vav-Cre+: n=10, Vav-Cre−: n=7. Mean ± s.e.m.