Analysis of Interleukin 22 Gene Expression in <i>Helicobacter pylori</i> -Infected Patients With Inflammation and Peptic Ulcer Compared to Uninfected Controls

Background and aims: Inflammation is a key feature of Helicobacter pylori infection and its associated complications, gastritis, and gastrointestinal ulcers. This study aimed to determine the level of expression of interleukin (IL)-22 in the gastric mucosa in the control group and patients with gastritis and peptic ulcer. Methods: This case-control study was conducted on patients with gastrointestinal problems referred to the endoscopy unit of Hajar Hospital of Shahrekord (Iran, 2018). Overall, 135 tissue samples were collected from people suspected of gastritis (n=45), people with peptic ulcers infected with H. pylori (n=45), and people without H. pylori infection (n=45). IL-22 gene expression was measured using a real-time polymerase chain reaction method compared to the beta-actin internal gene. IL-22 expression was calculated by 2-ΔΔct and statistically analyzed by SPSS16 software and t-student test. Results: In this research, the mean age of the patients was 50.17±15.09 and 50.96±19.77 in the infected and non-infected groups, respectively. There was no significant difference between the two studied groups in terms of age and gender (P=0.236). IL-22 expression in H. pylori-infected individuals (3.21±0.58) was 3.54-fold higher than that in the control group (0.9±0.14, P=0.036). Likewise, IL expression in peptic ulcer (2.2±0.43) was significantly higher than that in those with gastritis (1.12±0.87, P=0.012). Conclusion: Despite its pro-inflammatory nature, IL-22 can effectively control bacterial infections and strengthen mucosal defenses, particularly in the context of H. pylori infection, highlighting its therapeutic potential.