The Effect of TLR۴ Asp۲۹۹Gly polymorphism on IL-۶ and IL -۱۸ expression in H.pylori infected patients

Background & Aims: Helicobacter pylori (H. pylori) infection is associated with peptic ulcer and gastric cancer. Polymorphisms of the genes coding Toll-like receptors (TLRs) may influence the innate and adaptive immune responses and affect the susceptibility to H. pylori or the disease outcomes. But the details and association to different polymorphisms and different clinical expression in patients infected with H. pylori have remained unclear. The purpose of this study was to investigate the effect of TLR-۴ Asp۲۹۹Gly polymorphism on expression levels of IL-۶ and IL-۱۸ genes in patients infected with H. Pylori in comparison to uninfected patients. Methods: In a case-control study, biopsies were collected from ۵۸ H. pylori-infected and ۴۴ uninfected subjects.Genotypes of TLR-۴ Asp۲۹۹Gly single-nuleotide polymorphism were assessed through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The expression levels of mucosal IL-۶ and IL-۱۸ mRNA were measured by real time-PCR. Cytokine expression levels in the two groups were analysed using the t test. Results: The frequencies of D/D and D/G genotypes were respectively ۵۵.۲% and ۴۴.۸% in H. pylori-infected and ۷۷.۲% and ۲۲.۸% in uninfected subjects. The expression level of IL-۶ in H. pylori infected patients with TLR-۴ gene polymorphism was significantly higher (P=۰.۰۰۱). However, no significant relationship between the expression level of IL-۱۸ and TLR-۴ gene polymorphism was reported in patients infected with H. pylori (P=۰.۴۱۹). In addition, no significant relationship between IL-۶, IL-۱۸ expression levels and TLR-۴ gene polymorphism was reported in uninfected patients. Conclusion: TLR-۴ Asp۲۹۹Gly Gene single-nuclotide polymorphism increases the expression levels of TL-۶ and has an important role in development of Hopylori-associated gastrititis.

کلیدواژه ها:

Helicobacter pylori ، Polymorphism ، IL-۶ ، IL-۱۸ ، TLR-۴ ، Gastritis