旋毛虫对三硝基苯磺酸诱导的实验性小鼠肠炎模型的干预研究

Trichinella spiralis infection protects mice from TNBS-induced colitis

目的研究旋毛虫对三硝基苯磺酸(TNBS)诱导的实验性小鼠肠炎模型的影响及其免疫作用机制。方法观察感染和未感染旋毛虫小鼠于TNBS诱导肠炎后3 d及7 d不同指标的变化,包括小鼠生存率、疾病活动指数(DM)、结肠大体损伤和病理损伤评分、炎症指标髓过氧化物酶(MPO)活性检测,结肠细胞因子IFN-γ和IL-4 mRNA的表达量分析。结果预先感染旋毛虫后诱导TNBS模型组小鼠在造模后3 d及7 d与单纯模型组相比小鼠生存率升高(P<0.05),DAI、结肠大体损伤和病理损伤评分及MPO活性下降(P<0.05),结肠中IFN-γmRNA的表达量下调(P<0.05),而IL-4 mRNA的表达量增加(P<0.05)。结论旋毛虫对TNBS诱导的实验性小鼠肠炎具有良好的干预作用,其免疫作用机制可能是通过下调炎症性肠病过度的T_H1型免疫反应、上调T_H2型免疫反应而实现的。

Objective To study the effect of Trichinella spiralis （ T. spiralis ） protecting mice from TNBS-indueed colitis and the immunologic mechanism. Methods TNBS colitis with or without T. spiralis infection on days 3 and 7 post-induction of colitis was assessed on survival rate, DAI score, macroscopic damage and histological score, MPO activity assay, cytokine IFN-7 and IL-4 mRNA production assay. Results Compared with TNBS group, a faster increase in survival rate and decrease in DAI score, macroscopic damage and histological score, colonic MPO activity in T. spiralis ＋ TNBS group on days 3 and 7 post-induction of colitis（ P 〈 0.05）, IFN-7 mRNA production in colon were reduced in T. spiralis ＋ TNBS group on days 3 and 7 post-induction of colitis（P〈0.05）, IL-4mRNAlevelswereincreascd（P〈0.05）. Conclusion T. spiralis infection significantly attenuates TNBS induced colitis in the mice. The immunologic mechanism is that T. spiralis can down-regulate strong TH1-type immune response of colitis and up-regulate TH2 response.