CD4^＋CD25^＋T调节细胞参与感染弓形虫小鼠免疫应答调节的研究

目的观察弓形虫Prugniaud成囊株感染ICR小鼠后脾脏单个核细胞中不同T细胞亚群的比例在感染后不同时期的动态变化。方法用10个Prugniaud株弓形虫包囊以腹腔接种方式感染ICR小鼠，在小鼠感染前及感染后的1W，2W，3W，5W随机取6只小鼠，采用流式细胞仪对小鼠脾脏单个核细胞中Th1型和Th2型细胞及CD4^＋CD25^＋调节性T细胞比例变化进行动态检测。结果小鼠感染弓形虫后，Th1型细胞比例在感染后第1W一过性降低，后急剧升高，进入慢性感染期后又有所下降。Th2型细胞整个试验过程中呈现和Th1型细胞大致相反的变化趋势。CD4^＋CD25^＋T细胞在急性感染期，呈现和Th1型细胞相反的比例变化。结论CD4^＋CD25^＋调节性T细胞可能参与了弓形虫急性感染期的免疫抑制。

Study on the dynamic changes of different subsets of T cells in mice infected with Prugniaud strain Toxoplsama gondii

Objective To investigate the dynamic changes of different subsets of T cells in the Toxoplasma-infected mice. Methods ICR mice were infected intra-abdomianally with 10 cysts of the Prugniaud strain of T. gondii, Six mice were killed randomly and the percentages of Thl, Th2 and CD4^＋CD25^＋ T cells of spleen were determined by flow cytometry on week 0, 1, 2, 3, 5 after infection. Results It was found that the percentages of Th1 cells in the expermental mice dropped transiently then rose severely, compared with the change of Th1 cells, the percentages of Th2 presented roughly opposite tendency in the whole experiment and the CD4 ^＋CD25^ ＋ regulatory T cell presented conspicuous reverse change in the acute infection stage. Conclusion The regulation of CD4^＋CD25^＋ T cells may be one of the reasons leading to temporary immunosuppression on mice infected with T. gondii.