中药溃克灵对结肠炎模型大鼠CD4^＋CD25^＋调节性T细胞的影响

免疫调节异常在炎症性肠病（IBD）的发病中起重要作用，CD4^＋CD25^＋调节性T细胞（CD4^＋CD25^＋Freg）是一种免疫调节细胞，可维持机体免疫平衡。目的：观察中药溃克灵对结肠炎模型大鼠CD4^＋CD25^＋Treg的影响，探讨其治疗IBD的可能机制。方法：60只Sprague—Dawley大鼠随机分为正常对照组、结肠炎模型组和中药治疗组，采用TNBS诱导结肠炎模型．结肠炎急性期和缓解期分批处死大鼠。以流式细胞仪检测外周血CD4^＋CD25^＋Treg／CD4^＋T比例，以酶联免疫吸附测定（EUSA）检测血清白细胞介素（IL）－10和转化生长因子（TGF）－β1水平，并行结肠组织学评分。结果：与结肠炎模型组相比，中药治疗组大鼠一般情况和结肠组织学表现显著改善。结肠炎急性期．结肠炎模型组大鼠外周血CD4^＋CD25^＋Treg／CD4CF比例、血清IL-10水平显著低于正常对照组和中药治疗组（P〈0．05），中药治疗组大鼠结肠组织学评分显著低于结肠炎模型组（P〈0．05）。结肠炎缓解期．结肠炎模型组大鼠外周血CD4^＋CD25^＋Treg／CD4^＋T比例和结肠组织学评分显著高于正常对照组（P〈0．05）。结肠炎急性期和缓解期各组血清TGF—B1均无明显差异。结论：中药溃克灵对大鼠结肠炎有明显的治疗作用，可能与上调CD4^＋CD25^＋Treg、促进抗炎因子IL—10分泌有关。

Effect of Traditional Chinese Medicine Kuikeling on CD4+CD25+ Regulatory T Cells in Colitis Model Rats

Background： hnmune dysregulation plays an important role in the pathogenesis of inflammatory bowel disease （IBD）. CD4^＋CD25^＋regulatory T cells （CD4^＋CD25^＋Treg） is a kind of immunoregulatory cells for maintaining immune balance. Aims： To investigate the effect of traditional Chinese medicine Kuikeling on CD4^＋CD25^＋Treg in colitis model rats, and to elucidate the possible mechanism of Kuikeling in the treatment of IBD. Methods： A total of 60 Sprague-Dawley rats were randomly divided into three groups： normal control group, colitis model group and Kuikeling-treated group. Colitis model was induced by TNBS. The rats were killed separately in the acute and remission stages of colitis. Peripheral blood CD4^＋ CD25^＋Treg/CD4^＋T ratio was measured by flow cytometry. The levels of serum interleukin-10 （IL-10） and transforming growth factor-β1 （TGF-β1） were measured by enzyme-linked immunosorbcnt assay （ELISA）. The histological score of colon was evaluated. Results： Compared with the colitis model group, the general condition and histology of colon in Kuikeling- treated group were significantly improved. In the acute stage of colitis, peripheral blood CD4^＋CD25^＋Treg/CD4^＋T ratio and serum IL-10 in colitis model group were significantly lower than those in normal control group and Kuikeling-treated group （P〈0.05）. The histological score of colon in Kuikeling-treated group was significantly lower than that in colitis model group （P〈0.05）. In the remission stage of colitis, peripheral blood CD4^＋CD25^＋Treg/CD4^＋T ratio and histological score of colon in colitis model group were significantly higher than those in normal control group （P〈0.05）. There was no significant difference in serum TGF-β1 among the three groups in acute and remission stages of colitis. Conclusions： The traditional Chinese medicine Kuikeling has therapeutic effect on colitis in rats. The mechanism may be related to up-regulation of CD4^＋CD25^＋Treg and secretion of cytokine IL-10.