Increased numbers of foxp3-positive regulatory T cells in gastritis, peptic ulcer and gastric adenocarcinoma

AIM: To determine the number of regulatory T cells (Tregs) in gastric mucosa of patients with gastritis, peptic ulcers and gastric cancer. METHODS: This study was a retrospective analysis of gastric antrum biopsy specimens from healthy controls (n = 22) and patients with gastritis (n = 30), peptic ulcer (n = 83), or gastric cancer (n = 32). Expression of CD4, CD25 and Foxp3 was determined by immunohis-tochemistry in three consecutive sections per sample. RESULTS: Compared with healthy controls, there was an increased number of CD25⁺ and Foxp3⁺ cells in patients with gastritis (P = 0.004 and P = 0.008), peptic ulcer (P < 0.001 and P < 0.001), and gastric cancer (P < 0.001 and P < 0.001). The ratio of CD25⁺/CD4⁺ or Foxp3⁺/CD4⁺ cells was also significantly higher in all disease groups (P < 0.001, respectively). The number of CD4⁺, CD25⁺, and Foxp3⁺ cells, and the ratio of CD25⁺/CD4⁺ and Foxp3⁺/CD4⁺ cells, were associated with the histological grade of the specimens, including acute inflammation, chronic inflammation, lymphoid follicle number, and Helicobacter pylori infection. The number of CD4⁺, CD25⁺ and Foxp3⁺ cells, and the ratio of CD25⁺/CD4⁺ and Foxp3⁺/CD4⁺ cells, were negatively associated with intestinal metaplasia among gastritis (P < 0.001, P < 0.001, P < 0.001, P = 0.002 and P = 0.002) and peptic ulcer groups (P = 0.013, P = 0.004, P < 0.001, P = 0.040 and P = 0.003). CONCLUSION: Tregs are positively associated with endoscopic findings of gastroduodenal diseases and histological grade but negatively associated with intestinal metaplasia in gastritis and peptic ulcer groups.