TNF inhibits stromal cell-derived factor 1 expression by ST2 stromal cells. ST2 cells, a bone marrow stromal cell line, were treated with TNF or osteoclastogenic cytokines, and expression of stromal cell-derived factor 1 (SDF-1) mRNA was determined by real-time RT-PCR. (a) Data from the cells treated with TNF (10 ng/ml) for various time points (upper panel) or different amounts of TNF for 24 hours (middle panel). Changes in SDF-1 protein levels in the conditioned medium were determined by ELISA 24 hours after TNF treatment (lower panel). (b) Data from the cells treated with osteoclastogenic cytokines for 24 hours. Data are the mean ± standard error of the mean of three loadings. Data are representative of two independent experiments. *P < 0.05 compared with PBS-treated cells. TGFβ, transforming growth factor beta.
Zhang et al. Arthritis Research & Therapy 2008 10:R37 doi:10.1186/ar2391