复合法诱发小鼠结肠炎模型的建立和免疫学验证

目的:建立2,4-二硝基氯苯(DNCB)和醋酸(AA)复合法诱导的小鼠结肠炎模型,并验证其在炎性肠病(IBD)发病及治疗机制中的研究价值。方法:昆明种小鼠48只,按体重随机分为正常对照、模型、硫氮磺胺吡啶(SASP)及中药灌肠治疗4组,肠道积分法观察组织病理学变化;DAPI染色检测淋巴细胞凋亡指数的改变;流式细胞仪分析外周血中CD4~ CD29~ T细胞及外周血和肠系膜淋巴结中CD3~ 、CD4~ T细胞的变化。结果:成功建立免疫型小鼠结肠炎模型。模型组小鼠肠道病理学损伤较正常对照组明显加重;特别是模型组CD4~ CD29~ T细胞比例明显高于正常对照组(P<0.01);免疫组织淋巴细胞凋亡指数显著升高(P<0.01);而CD3~ 、CD4~ T细胞较正常对照组明显降低(P<0.05)。经SASP和中药灌肠治疗后,肠道组织病理损伤明显减轻,免疫组织淋巴细胞凋亡指数显著降低,且CD3~ 、CD4~ T细胞亚群较模型组明显增高。结论:DNCB AA法诱导的小鼠结肠炎模型,是一种较理想的IBD动物模型,可成功用于炎性肠病发病及治疗机制的研究。

Reproduction and immunological authentication of marine model of colitis induced by a combination of dinitrochlorobenzene and acetic acid

Objective:To reproduce a dinitrochlorobenzene(DNCB)and acetic acid(AA)-induced murine colitis model and to assess its significance in the study of pathogenesis of inflammatory bowel disease(IBD).Methods: Adult KM mice were randomly divided into four groups:normal control group,model group,salicylazosulfapyri- dine(SASP)treatment group and traditional Chinese medicine(TCM)treatment group.Except the normal con- trol group,ulcerative colitis was reproduced with DNCB and AA in mice of other groups.After the model was es- tablished,SASP(200 rag/L)or compound 1 TCM(1.2 g/ml)were clystered respectively in the SASP group and TCM treatment group with a dose of 0.25 mi,once per day for 1 or 2 weeks.At the same time,the same dosage of normal saline was clystered in the normal control and model groups.After 1 and 2 weeks,histopathological changes were examined and pathological score of intestinal lesion were recorded.Apoptotic lymphocytes were i- dentified with May-Grounwald-Giemsa(MGG)and proportions of CD4~ CD29~ T cell in peripheral blood and CD3~ ,CD4~ T cells in peripheral blood and mesenteric lymph node of each group were estimated by flow cytome- try.Results:The model of experimental colitis in mice was successfully reproduced.Compared with normal con- trol group,the pathological score was markedly higher,indicating that the pathological changes in intestine in coli- tis model group was more intensive.Especially,the proportion of CD4~ ,CD29~ T cell in model group was obvi ously higher than that in normal control group(P<0.01).The number of apoptotic lymphocytes of immune tis- sues in model group were significantly greater than those of normal control group(P<0.01).On the other hand, the proportions of CD3~ and CD4~ T cells were evidently decreased(P<0.05).After two weeks' treatment with SASP or TCM,the injury of intestine as estimated by pathological score was distinctively alleviated,and at the same time,apoptotitc index of lymphocyte in immune tissues was distinctively lowered,and it was accompanied by a significant increase in the proportion of CD~3~ ,CD4~ T cells in peripheral blood and lymph node as compared with the model group.Conclusion:DNCB and AA-induced murine colitis is an ideal animal model of IBD,and might serve as a good tool for investigation of the pathogenesis and treatment of IBD.