Figure 7.

Immunohistochemical staining demonstrating that pathophysiological concentrations of IL-13 can synergize with TNF-α to enhance VCAM-1 expression on fibroblast-like synoviocytes. Cultured FLS were treated with IL-13 at 0.1, 1, and 10 ng/ml as indicated and TNF-α (10 ng/ml) for 4 days. FLSs were fixed with methanol and acetone and then stained with mouse anti-human VCAM-1 mAb (BBA-5) and visualized using the streptavidin-biotin-peroxidase method. The results shown are representative of four separate experiments.