中文摘要：

目的体外观察妊娠浓度的雌激素（E2）能否诱导天然CD4＋CD25＋未Treg细胞的增殖并增强其抑制功能。方法-天然CD4＋CD25＋Treg细胞的增殖检测：CFSE标记天然CD4＋CD25＋Treg细胞作为反应细胞预先经妊娠水平的E2孵育2h后，加入抗CD3／CD28单抗体外培养。以是否经E2孵育或加入抗CD3／CD28单抗分为2个阴性对照组和空白对照组。120h后检测天然CD4＋CD25＋Treg细胞的增殖情况。天然CD4＋CD25Treg细胞的功能检测：以CFSE标记CD4＋CD25naiveT细胞作为反应细胞与预先经E2孵育2h的天然CD4＋CD25＋Treg细胞共培养，并于其中加入抗CD3／CD28单抗。以是否经E2孵育或加入抗CD3／CD28单抗分为2个阴性对照组和空白对照组。120h后检测CD4＋CD25 naive T细胞的增殖情况。结果增殖检测提示两阴性对照组与空白对照组天然CD4＋CD25＋Treg细胞无明显增殖，而实验组则较对照组增殖明显；功能检测提示空白对照组标记细胞不发生明显增殖，阴性对照组A中标记细胞增殖明显；实验组标记细胞增殖能力在经E2孵育的天然CD4＋CD25＋Treg细胞作用下受到明显抑制；与阴性对照组A和空白对照组差异均有显著性；阴性对照组中标记细胞的增殖也被明显抑制，与阴性对照组A比较差异有显著性，但同时其增殖抑制作用又弱于实验组，差异也有显著性。结论体外实验表明，妊娠状态下高水平的雌激素能通过促使天然CD4＋CD25＋Treg细胞的扩增而增强其抑制功能。

英文摘要：

Objective To investigate whether the pregnant-level estrogen induce the expansion of CD4＋ CD25＋ regulatory T cells and its suppression activity in vitro. Methods ① CD4＋ CD25＋ regulatory T cells labelled with CFSE were stimulated with anti-CD3 and anti-CD28 mAbs or PBS in the presence and absence of pregnant level estrogen （ E2 ） （ experimental group, control group A and control group B）, or no any stimulus instead of PBS （placebo group）. ②CFSE-labelled CD4＋ CD25＋ naive T cells were cultured with CD4＋ CD25＋ regulatory T cells, which were pretreated for 2 hours with estrogen or not, and stimulated with anti- CD3 and anti-CD2s mAbs or PBS （experimental group, control group A and control group B）. As placebo group, CFSE-labelled CD4＋ CD25＋ naive T ceils were treated only with PBS. After 120 hours, the proliferation of labelled cells was detected by FACS and analyzed by Modfit LT soft. Results Stimulated by anti-CD3 and anti-CD2s mAbs in 120 h, the proliferation index （PI） of CD4＋ CD25＋ regulatory T cells in experimental group were significantly higher than that in two control groups and placebo group. The proliferation of CFSE-labelled CD4＋＋ CD25＋ naive T cells mediated with anti-CD3 and anti-CD2s mAbs was inhibited by CD4＋ CD25＋ regulatory T cells, estrogen pretreated CD4＋ CD25＋ regulatory T cells could further enhance this effect. Conclusion It suggested that high level of estrogen in gestation can induce the expansion of CD4＋ CD25＋ regulatory T cells and enhance its suppression, and may play a pivotal role in the matemal-feto tolerance.