胃粘膜Hp感染与细胞凋亡和Fas抗原表达的关系

Gastric epithelial apoptosis induced by Helicobacter pylori and its relationship with Fas antigen expression

目的 通过观察幽门螺杆菌 (Hp)感染诱导胃粘膜上皮细胞凋亡与Fas抗原表达的关系 ,探讨Hp诱导胃粘膜上皮细胞凋亡的机制。方法 采用脱氧核糖核酸末端转移酶介导的缺口末端标记 (TUNEL)技术原位观察和比较Hp根除前后胃粘膜上皮细胞凋亡的变化 ,采用免疫组织化学染色检测Fas抗原表达变化。结果 Hp阳性患者胃粘膜上皮细胞凋亡指数为 12 .78% ,明显高于Hp阴性者 (3 .63 % ,P <0 .0 1) ;Hp根除后胃粘膜上皮细胞凋亡指数 (4.3 7% )较治疗前明显降低 (12 .46% ,P <0 .0 1) ,而持续阳性者凋亡指数无明显降低。Hp阳性患者胃粘膜上皮细胞Fas抗原表达率为 67.92 % ,高于Hp阴性者 (45 .0 0 % ) ;Fas抗原表达阳性的Hp阳性患者在Hp根除后Fas抗原细胞密度显著减少 (P <0 .0 1) ,而Hp未被根除者Fas抗原表达阳性细胞密度无明显变化。结论 Hp感染可诱导胃粘膜上皮细胞凋亡 ,这可能是Hp参与胃癌发生的重要机制之一 ;Hp感染可促进Fas抗原表达增加 ,这可能是Hp感染诱导胃粘膜上皮细胞凋亡的机制之一。

Objective To study the relationship between gastric epithelial apoptosis induced by Helicobacter pylori and Fas antigen expression and explore the mechanisms of H. Pylori infection that induce gastric epithelial cell apoptosis. Methods The apoptotic cells and FAS antigen expression in situ in H. pylori negative gastric mucosa, H. pylori positive gastric mucosa before and after H. pylori eradication were observed with terminal deoxynucleotidyl transferase mediated nick end labeling (TUNEL) technique and immunohistochemical staining. Results The apoptotic index of gastric epithelial in the patients infected with H. pylori (12.78%) was significantly higher than that of H. pylori negative gastric epithelia (apoptotic index 3.63%, P <0.01). After eradication of H. pylori with triple therapy, the apoptotic index fell from 12.37% to 4.46% ( P < 0.01) . In the persisting H. pylori infected patients, the apoptotic index was not statistically decreased. The positive rate of Fas antigen of gastric epithelia in the patients infected with H. Pylori (67.92%) was higher than that of H. pylori negative gastric epithelia (45.0%). After eradication of H. Pylori with triple therapy, the Fas antigen positive cell density was significantly decreased ( P <0.01). In the persisting H. pylori infected patients, the positive cell density was not significantly decreased. Conclusion These results suggest that H. pylori could induce gastrc epithelial apoptosis in vivo . H. pylori increases the expression of Fas antigen, which might be one of the mechanisms by which H. pylori promotes gastric epithelial apoptosis.