肠易激综合征患者肠黏膜Th1/Th2漂移的研究

Study on the shifting of Th1/Th2 balance of large intestinal mucosa in patients with irritable bowel syndrome

目的 探讨肠易激综合征 (IBS)患者肠黏膜是否存在Th1/Th2免疫调节功能紊乱。方法 经结肠镜钳取 5 8例IBS患者及 2 0例对照者的升结肠、降结肠和直肠黏膜标本 ,采用免疫组化染色检测其肠黏膜主要Th1和Th2细胞因子的表达情况。结果 IBS患者肠黏膜大体及组织学表现与对照相比无明显改变 ;腹泻型IBS患者升结肠、降结肠、直肠黏膜Th1细胞因子干扰素 (IFN) γ的阳性表达率显著高于对照组 ,白细胞介素 (IL) 12的表达率在直肠较对照组显著增高 ,升结肠、降结肠有升高趋势 ,但差异无显著性 ;Th2细胞因子IL 10的表达率与对照组比较呈降低趋势 ,但差异无显著性。进一步比较腹泻型患者中感染后IBS(pIBS)和非感染后IBSTh1和Th2细胞因子的表达 ,pIBS中Th1细胞因子IFN γ的表达在升结肠、降结肠和直肠均显著高于对照组 ,升结肠、直肠IL 12的表达亦显著增高 ,降结肠的表达有增高趋势 ;Th2细胞因子IL 4、IL 10较对照组有下降趋势。非感染后IBS患者Th1和Th2细胞因子的表达较对照组差异无显著性。便秘型IBS患者Th1和Th2细胞因子的表达与对照组比较差异均无显著性。结论 腹泻型IBS患者肠黏膜内存在Th1/Th2漂移 ,Th1反应增强 ,感染因素影响了腹泻型Th1/Th2漂移 ,便秘型患者Th1/Th2仍趋于平衡状态。

Objective To investigate possible disturbance of Th1/Th2 immunoregulation of large intestinal mucosa in patients with irritable bowel syndrome (IBS). Methods Mucosal specimens were harvested from ascending, descending colon and rectum by colonoscopy in 58 patients with IBS and 20 healthy controls. The expressions of Th1 and Th2 cytokines were determined by immunohistochemical staining. Results The large intestinal mucosa of patients with IBS were general normal both under colonoscopy and conventional histological assessment on hemotoxylin and eosin stained (H E) sections. Compared with controls, the expressions of Th1 cytokine (IFN γ) in the ascending, descending colon and rectum were significantly increased in diarrhea predominant IBS (D IBS) patients. The expression of interleukin 12 (IL 12) in the rectum was also significantly increased. However, the expressions of Th2 cytokines (IL 10)) in D IBS patients were decreased, but no significant difference compared with controls. The expressions of IFN γ in post infection IBS (pIBS) patients were increased significantly compared with controls among D IBS patients. Besides, IL 12 in the ascending colon and rectum were significantly increased. The expressions of IL 4 and IL 10 in pIBS patients were decreased, but no significant difference compared with controls. The expressions of Th1 and Th2 cytokines in non pIBS patients have no significant difference compared with controls. In constipation predominant IBS (C IBS) patients, the expressions of Th1 and Th2 cytokines had no statistical difference compared with controls. Conclusions The shift of Th1/Th2 balance of colon and rectal mucosa in D IBS patients was demonstrated along with the enhanced Th1 activity. Infection affected the shift of Th1/Th2 balance in D IBS patients. Th1/Th2 balance has been maintained in C IBS patients.