副结核杆菌和克隆病肠粘膜匀浆致地鼠肠炎的比较研究

COMPARATIVE STUDY OF ENTERITIS INDUCED BY MYCOBACTERIUM PARATUBERCULOSIS AND TISSUE HOMOGENATES OF CROHN'S DISEASE IN HAMSTERS

目的 探讨副结核杆菌（ＭＰ）在克隆病（ＣＤ）病因学中的作用。方法 将ＭＰ接种地鼠。诱导肉芽肿性肠炎动物模型，然后用一部分ＣＤ肠粘膜匀浆作ＰＣＲ扩增ＭＰ，另一部分肠壁接种地鼠。结果 ＭＰ接种８ 月后，有８０％ （１６／２０）出现肉芽肿性改变，ＰＣＲ阳性ＣＤ匀浆肠壁接种４月后，有５ 只出现肉芽肿性改变，与ＭＰ组的病理改变相似。ＰＣＲ阴性ＣＤ匀浆组有一只出现肉芽肿性改变。结论 ＭＰ可能为部分ＣＤ的致病菌。

Aim\ A comparison of the macroscopical and histological appearance in granulomas was made induced by Mycobacterium Paratuberculosis(MP) and Crohn's Disease(CD) tissue in hamsters,in order to investigate whether MP plays an etiologic role in CD.Methods\ 40 hamsters were inoculated intraperitoneally,twenty received MP,ten received dead inoculum and ten received saline.Each CD homogenated was prepared immmediately after biopsy,100μl homogenates was analysed by PCR;and 40μl was inoculated intramurally into the cecum and terminal ileam of each hamster of 5,tissue was obtained from intestine and evaluated macroscopically nad histologically.Each hamster inoculated intramurally was scored on the criteria for assessment of intestine damage.Results\ Microscopically,16 of 20 hamsters received MP showed granulomatous changes,the control hamsters didn't show granulomatous enteritis.Two of five CD homogenates were positive for MP.The hamsters received PCR positive CD homogenates put on granulomatous changes involved in 5 of 10.The correct 400bp amplification product was obtained again in the granulomatous intestinal tissue of 5 hamsters inoculated PCR positive CD homogenates when the IS900 PCR was applied.Only 1 of 15 hamsters received PCR nagative CD homogenates showed granulomatous change.The average score of hamsters intestinal damage induced by PCR negative CD homogenates was 3 66±1 71 and showed a marked increase(P<0 05) as compared with those of normal gut mucosa group;but no statisically significant difference(P>0 05) was shown when compared with PCR positive CD homogenates group.Conclustion\ MP may play an etiologic role in at least some cases of Crohn's disease.Other factor may also play an etiologic role in some cases of CD except MP.