日本血吸虫卵抗TNBS诱导的小鼠结肠炎的观察

Suppression of Schistosoma japonicum Eggs on TNBS-induced Colitis in Mice

目的探讨日本血吸虫卵对2,4,6三硝基苯磺酸(TNBS)诱导的小鼠结肠炎的抑制作用。方法50只6～8周龄BALB/c雌性小鼠随机分为正常对照组、乙醇对照组、虫卵对照组、结肠炎组和虫卵免疫结肠炎组,10只/组。虫卵免疫结肠炎组以日本血吸虫卵经腹腔注射免疫小鼠4次,10000个卵/鼠,每次间隔1周,末次免疫后6d用TNBS诱导结肠炎模型。观察对照组和实验组小鼠的体重、结肠病理改变及细胞因子水平的变化。结果结肠炎组小鼠经TNBS诱导后,出现明显的粘液血便、体重下降、结肠充血水肿,肠黏膜呈现严重炎性浸润伴溃疡,IFN-γ水平为(3.47±0.87)ng/ml,IL-4水平为(146.06±45.76)pg/ml。虫卵免疫结肠炎组小鼠症状较轻,体重恢复较快,IFN-γ表达被明显抑制,其水平为(1.53±0.51)ng/ml,IL-4水平显著升高至(598.50±135.90)pg/ml。结论日本血吸虫卵对TNBS诱导的BALB/c小鼠结肠炎具有抑制作用。

Objective To study the suppression of Schistosoma japonicum eggs against the trinitrobenzene sulfonic acid （TNBS）-induced colitis in mice. Methods 50 female BALB/c mice （6-8 week-old） were randomly divided into normal control group, ethanol control group, schistosome egg immunized control group, TNBS-induced colitis group and TNBS-induced colitis with egg immunization group. In TNBS-induced colitis with egg immunization group, mice were immunized 4 times with 10 000 schistosome eggs by intraperitoneal injection with one-week interval. On day 6 after the last immunization the mice were induced by TNBS and the body weight, histological change on colon and level of cytokines of mice were observed in egg-immunized and -unimmunized colitis mice. Results The unimmunized mice developed significant inflammation in colon with bloody mucus feces and decreased body weight after TNBS induction. Distinct hyperemia, edema and transmural inflammatory infiltration accompanied with ulceration were shown in colon. The level of IFN-γ was （3.47±0.87） ng/ml and IL-4 was （146.06±45.76） pg/ml. However, in egg-immunized mice, the inflammation was suppressed greatly and the body weight recovered soon after TNBS induction. The production of IL-4 was enhanced to （598.50±135.90） pg/ml, and IFN-γ was significantly diminished to （1.53±0.51） ng/ml. Conclusion S.japonicum eggs protect mice from colitis induced by TNBS.