CXCL4 knockout in hematopoietic cells in ThPO-induced PMF decelerates the progression of fibrosis. (A) BM cellularity at 9 weeks’ posttransplantation. (B) Myelofibrosis grading and representative images of reticulin staining of the BM in ThPO-induced and control mice, and hematoxylin and eosin (HE) staining highlighting osteosclerosis in WT ThPO mice. Kruskal-Wallis multiple comparison test. Scale bar, 100 μm. (C) Spleen weight relative to body weight at 9 weeks’ posttransplantation. (D) Flow cytometric analysis of the frequency of GFP⁺Lin^lowSca1⁺ ckit⁺ cells in the spleen. (E) Representative immunofluorescence images and flow cytometric analysis and quantification of Gli1⁺tdTomato⁺ fibrosis-driving stromal cells in the BM. Scale bar, 50 μm. Data are shown as mean ± standard error of the mean, n = 5 per group, 1-way analysis of variance followed by Tukey’s post hoc test. *P < .05, **P < .01, ***P < .001, ****P < .0001. ns, not significant.