Figure 3 Representative western blots showing MMP‐1, MMP‐2, MMP‐3, MMP‐9, TIMP‐1 and TIMP‐2 in fibroblasts isolated from the colon of one patient with Crohn's disease (CD), and either left untreated or treated with graded doses of interleukin (IL) 21 for 48 h. One of 12 separate experiments is shown. In the last lane (+ve), total proteins extracted from the inflamed colon of a patient with Crohn's disease were used as a positive control. The right inset shows a representative zymogram of gelatinolytic activities in supernatants from Crohn's disease fibroblasts either left unstimulated (Unst) or stimulated with 50 ng/ml IL21 for 48 h. MMP, matrix metalloproteinase; TIMP, tissue inhibitor of metalloproteinase.