Increased expression of matrix metalloproteinase-9 associated with gastric ulcer recurrence

Figure 3 Production of matrix metalloproteinase-9 or tissue inhibitor of metalloproteinase-1 by gastric mucosa with negative or positive H. pylori-infection in patients with gastric ulcer (n = 63) or chronic superficial gastritis (n = 25). A: Tissue culture was performed for 24 h. Matrix metalloproteinase (MMP)-9 concentration in tissue culture supernatants was measured by enzyme-linked immunosorbent assay (ELISA); B: Tissue culture was performed for 24 h. Tissue inhibitor of metalloproteinase (TIMP)-1 concentration in tissue culture supernatants was measured by ELISA. GU: Gastric ulcer; CSG: Chronic superficial gastritis; H. pylori: Helicobacter pylori.