TLR۴ and TLR۲ Expression in Biopsy Specimens from Antral and Corporal Stomach Zones in Helicobacter pylori Infections

Background: It is not yet known which types of Toll-like receptors (TLRs) are most effective in Helicobacter pylori (H. pylori) recognition. It is also not known which gastric zones have the most prominent roles in TLR-mediated bacterial recognition. The aim of this work was to analyze the expression of TLR۲ and TLR۴ in biopsy specimens from H. pylori-infected patients. Methods: Thirty-eight patients with gastrointestinal disorders were divided into four groups in this study. The groups were: (A) H. pylori infection and peptic ulcer (n=۱۵), (B) peptic ulcer only (n=۵), (C) H. pylori infection only (n=۱۰) and (D) control, with neither H. pylori infection nor peptic ulcer (n=۸). Biopsy specimens from sites of redness or atrophic mucosa from gastric antrum and body in patients with gastritis were collected. RNAs from the antrum and body specimens were isolated. TLR۲ and TLR۴ mRNA expression was assessed by RT-PCR and quantified as densitometric ratios of TLR۲ and TLR۴/β-actin mRNA. Results: In the antral zones of H. pylori-infected patients (Groups A and C) TLR۲ and TLR۴ expression was significantly greater than in uninfected patients (Groups B and D) regardless of peptic ulcers (p < ۰.۰۵). In the gastric body samples TLR۲ expression was significantly greater in Group C (H. pylori infection only) than in Group B (peptic ulcer only) and TLR۴ expression was significantly greater in group A (H. pylori infection and peptic ulcer) than in Group B (peptic ulcer only) (p < ۰.۰۵). No significant differences in expression of TLR۴ and TLR۲ were observed between samples from the antrum and body in same groups. Conclusions: We conclude that H. pylori infection leads to significant increase in TLR۲ and TLR۴ molecules expression in antral region related to the control group. Considering the stimulatory effect of H. pylori on TLRs expression in the gastric tissue, we assume that colonization of H. pylori infection might occurs more in the gastric antral region than in the gastric body.

کلیدواژه ها:

Helicobacter pylori ، Peptic ulcer ، TLR۲ ، TLR۴ ، Toll-like receptors