目的:观察CD4+T细胞及其共刺激分子(CSF)在湿热型溃疡性结肠炎(UC)大鼠肠黏膜中的表达及分布,探讨黄芩汤治疗该病可能的免疫学机制。方法:采用高脂、高糖饲料联合人工气候箱法造出湿热型体质,结合三硝基苯磺酸(TNBS)灌肠法建立湿热型UC模型;造模成功后将大鼠分为模型组、黄芩汤组及美沙拉嗪组,用免疫组化SP法检测大鼠结肠黏膜CD4+T细胞,CD28,CD152,OX40T细胞亚型的表达及分布,通过图像数码采集系统及Imageproplus6.0软件分析平均光密度,以检测各分子表达含量。结果:与正常对照组比较,造模大鼠结肠中CD4+T细胞、CD28,CD152,OX40等T细胞亚型升高(P〈0.05),主要分布于黏膜下层及固有肌层;治疗后,黄芩汤和美沙拉嗪组大鼠结肠中CD4+T细胞,CD28,OX40T细胞亚型表达均下降(P〈0.05),但CD152的表达无明显变化且维持在模型组水平;黄芩汤组及美沙拉嗪组以上各分子的表达均无统计学差异。结论:黄芩汤可能通过调节CD4+T细胞的CSF的表达含量从而发挥对溃疡性结肠炎的免疫调节作用。
Objective:To observe the expression and localization of CD4+T cell and its co-stimulator factors (CSF) in the mucosa of ulcerative colitis(UC) rat with damp-and-heat syndrome, and to explore the conceivable immunology mechanism of Huangqin decoction to treat the disease. Method:The model of UC rats with damp-andheat syndrome were established by giving the high sugar fat food and put into an artificial bioclimatic chamber, resulting in damp-and-heat body constitution and then elysmaed with 2,4,6-trinitro-benzene-sulfonic acid. After that the rats were divided into the model group, Huangqin decoction group and mesalazine group. SP of Immunohistochemistry was used to determine the expression and localization of CD4+T cell, CD28,CD152, OX40 T cell subsets in mucosa. The above antigens were tested using Image pro plus 6.0, an image acquisition system based on the digital camera and software, by analyzing their mean density. Result:Compared with the normal rats (n = 15) , the expression of CD4 + T cell, CD28, CD152 and OX40 T cell subsets in mucosa increased for the model rats(n = 38 in total and P 〈 0.05 ), and targeted to distribution in the submucosa and inherent layers. Compared with the model control group (n = 12) , CD4+T cell, CD28 and OX40 in both Huangqin decoction (n =13) and mesalazine group (n = 12) decreased (P 〈0.05), but CD152 did not ,kept in the level of model gruop. There was no statistical difference of the level of the above antigens between Huangqin decoction (n = 13) and mesalazine group (n = 12, P 〉 0.05). Conclusion: It is possible that the expression of the CSF for CD4+T cells maybe the immunology mechanism of the decotion to treat UC.