Effects of passages, starvation, cytokines and growth factors on ADAM15 expression in cultured cells. The mRNA expression of ADAM15 was examined by RT-PCR at 25 cycles as described in Materials and methods. (a) Effect of passages on the mRNA expression of ADAM15 in rheumatoid arthritis (RA) synovial fibroblasts (SFs). Lanes 1 to 5 indicate passages 5, 6, 7, 8 and 9 of RA SFs. (b) Effect of starvation on the mRNA expression of ADAM15 in RA SFs. (c) Effect of tumor necrosis factor (TNF)-α (0, 0.1, 1 and 10 ng/ml), IL-1α (0, 0.1, 1 and 10 ng/ml) or transforming growth factor (TGF)-β (0, 0.1, 1 and 10 ng/ml) on the mRNA expression of ADAM15 in RA SFs after stimulation with these factors for 24 h. (d) Regulation of the mRNA expression of ADAM15 by vascular endothelial growth factor (VEGF)165 in RA SFs and human umbilical vein endothelial cells (HUVECs). Cells were stimulated with VEGF165 (0, 1, 10 and 50 ng/ml) for 24 h. Note that VEGF165 enhances the expression of ADAM15 only in HUVECs.