CD_4^+Th细胞在噁唑酮诱导的小鼠实验性肠炎中的变化

Change of CD_4^+ T help cells on oxazolone induced colitis in mice

目的研究CD4+Th细胞在口恶唑酮诱导的小鼠实验性肠炎中的变化及肠炎的发病机制。方法健康昆明小鼠24只随机平均分为正常组和模型组(以口恶唑酮灌肠造模)。造模3 d后全部处死,提取外周血单个核细胞(PBMC)、脾脏单个核细胞(SMC)和肠黏膜固有层单个核细胞(LPMC)进行细胞培养,并利用细胞内细胞因子流式检测法测定Th1/Th2比例。结果培养48 h后,模型组的LPMC中Th1细胞百分比和Th2细胞百分比均比正常组明显上升(P<0.01),Th1/Th2比正常组显著下降(P<0.01)。培养96 h后,模型组的LPMC中Th1细胞百分比与正常组相比差异无统计学意义(P>0.05),Th2细胞百分比较正常组明显上升(P<0.01),Th1/Th2比正常组显著下降(P<0.01)。而2组的PBMC和SMC相比Th1、Th2细胞百分比和Th1/Th2差异均无统计学意义(P>0.05)。结论口恶唑酮诱导的小鼠实验性肠炎是一种Th2亚群占优势的肠黏膜局部免疫紊乱。

AIM To investigate the change and mechanisms of CD4^＋ T help cells on oxazolone induced colitis in mice. METHODS Twenty-four mice were randomized into 2 groups（ n = 12） ： normal group and model group. The mice in model group were induced by oxazolone enema. All mice were sacrificed 3 d after enema, peripheral blood mononuclear cells （PBMC）, spleen mononuclear cells （SMC） and lamina propria mononuclear cells （LPMC） were isolated from freshly tissue, and the ratios of Th1/Th2 were detected by flow cytometry with two color intracellular cytokine staining. RESULTS After 48 h cell culture, Thl cell and Th2 cell of LPMC in model group were significantly higher than those in normal group （P 〈 0.01）, and Th1/Th2 of LPMC in model group was significantly lower than that in normal group （P 〈 0.01 ）. After 96 h cell culture, Th1 cell of LPMC in model group was no significant statistical difference as compared with that in normal group （ P 〉 0.05 ）, while Th2 cell was significantly higher than that in normal group （ P 〈 0.01）, and Th1/Th2 of LPMC in model group was significantly lower than that in normal group（ P 〈 0.01） .In PBMC and SMC from the model group, Th1 cell, Th2 cell and Th1/Th2 were no significant statistical difference compare to those in normal group（ P 〉 0.05）. CONCLUSION The results indicate that the oxazolone induced colitis in mice is a local immunologic derangement characterized by predominant Th2 response.