Fig. 2

IL-34 and colony stimulating factor-1 (CSF-1) macrophages have similar phenotypic characteristics. a Fluorescence-activated cell sorting (FACS) analysis of Annexin V-propidium iodide (PI) staining in macrophages differentiated for 7 days in granulocyte-macrophage colony-stimulating factor (GM-CSF) (5 ng/ml), CSF-1 (25 ng/ml) or IL-34 (25 ng/ml) from peripheral blood and synovial fluid of healthy donors (HD) and patients with rheumatoid arthritis (RA). Data are presented as percentage of double-positive cells and represent the mean ± standard error of the mean (SEM) of 3–4 independent experiments. b, c FACS analysis of expression of macrophage surface markers CD14, CD163, CD206, and CD64 in macrophages differentiated for 7 days in GM-CSF, CSF-1 or IL-34 derived from monocytes of buffy coat (b) or monocytes from peripheral blood of HD or patients with RA (PB), or from synovial fluid from patients with RA (SF) (c). Data are presented as the geometric mean (geo mean) and represent the mean ± SEM of 4–5 independent experiments per marker. *P < 0.05, **P < 0.01, and ***P < 0.001