Role of Chitinase 3–like‐1 in Myelofibrosis via Fibroblast‐Produced Extracellular Matrix Enhancement

mice, based on romiplostim or Janus kinase 2 mutations, revealed fewer reticular fibers in silver-stained BM slices than in wild-type mice. A culture assay revealed that high CHI3L1 concentrations promoted extracellular matrix production by fibroblast cell lines, and that a CHI3L1-neutralizing antibody abrogated this effect. These results indicate the importance of CHI3L1 in the association between fibrocytes and fibroblasts in MF and could be a focus for future treatment.