Skip to main content
. 2017 Apr 27;18(5):920. doi: 10.3390/ijms18050920

Figure 1.

Figure 1

YKL-40 increases IL-18 expression in osteoblasts and promotes endothelial progenitor cell (EPC) angiogenesis. (A–C) MG-63 cells were treated with prespecified concentrations of YKL-40 (0–10 ng/mL) for 24 h. IL-18 expression was examined by qPCR, Western blotting, and ELISA (n = 4 per group). (D,E) MG-63 cells were treated with YKL-40 (0–10 ng/mL), or pretreated for 30 min with control IgG or IL-18 antibody for 30 min then stimulated with YKL-40 (10 ng/mL) for 24 h. Medium was collected as collected medium (CM). Two hundred microliters of 20% FBS MV2 medium and 150 μL of osteoblast CM was then applied to EPCs. Capillary-like structure formation and in vitro cell migration in EPCs was examined by tube formation and Transwell assay. Direct application of YKL-40 had no effect upon EPC tube formation and migration (n = 5 per group). (F) MC3T3-E1 cells were treated with prespecified concentrations of YKL-40 (0–10 ng/mL) for 24 h. IL-18 mRNA expression was examined by qPCR (n = 3 per group). Results are expressed as the mean ± S.E. * p < 0.05 compared with control. # p < 0.05 compared with the YKL-40-treated group.