Requirement for dectin-1 and cell-cell interactions in upregulation of cyclo-oxygenase 2 (COX-2) expression (measured by RT-PCR) in synovial fibroblasts infected with Candida albicans. (a) Synovial fibroblasts were infected with C. albicans in the absence or presence of 10 mg/ml laminarin and COX-2 gene expression assessed. In the presence of C. albicans COX-2 gene expression by synovial fibroblasts is increased (*P < 0.05 C. albicans vs phosphate-buffered saline (PBS)). This increase in COX-2 gene expression is decreased by around 20% by laminarin (#P < 0.05 laminarin + C. albicans vs C. albicans alone). (b) Synovial fibroblasts and C. albicans were seeded in different chambers of trans-well plates overnight followed by 12 h of chamber interaction and subsequent assessment of COX-2 gene expression in synovial fibroblasts (lanes 1 and 2) and C. albicans (lane 3). Lane 1: synovial fibroblasts in the upper chamber and no C. albicans in the lower chamber. Lane 2: synovial fibroblasts in the upper chamber and C. albicans in the lower chamber. Lane 3: empty upper chamber and C. albicans in the lower chamber. RT-PCR using the RNA from C. albicans showed no band of COX-2 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) (N = 5, * P < 0.05).