<qa>  What is the name of the fibrocytes?A possible FLS cell precursor has been identified in peripheral blood and called fibrocytes. Fibrocytes are spindle-shaped cells that express surface receptors of both stromal and hematopoietic cells. The fibrocytes are a rare 0.5 of leukocytes population of bone marrow derived mesenchymal progenitor cells. A combination of markers that distinguish fibrocytes from monocytes, macrophages and fibroblasts has been described. In vitro circulating human peripheral blood mononuclear cells and monocytes CD14 can differentiate into fibrocytes. Fibrocytes can differentiate in vitro along multiple mesenchymal lineages into adipocytes, chondrocytes, myofibroblasts and osteoblasts. It is unknown which differentiation pathway occurs in vivo or if multiple differentiation profiles can occur . 