目的了解血必净注射液促进LPS刺激CD4^+CD25^+调节性T淋巴细胞(Treg细胞)凋亡过程及介导辅助性T淋巴细胞(Th)漂移的调节作用。方法免疫磁珠法分选获得大鼠脾脏CD4^+CD25^+Treg细胞,分为常规培养对照组、抗CD3/CD28组、抗CD3/CD28+LPS组、抗CD3/CD28^+血必净组和抗CD3/CD28+LPS+血必净组,培养3d后应用流式细胞术检测Treg细胞凋亡率及叉头翼状螺旋转录因子3(Foxp3)表达。将CD4^+CD25^+Treg细胞与CD4^+CD25^-T淋巴细胞1:1培养,伴刀豆球蛋白A刺激68h,检测上清液中Th1分泌的γ干扰素(IFN-γ)、Th2分泌的IL-4、Th17分泌的IL-17水平。结果抗CD3/CD28+LPS+血必净组Treg细胞凋亡率为(45.14±2.7)%,明显高于抗CD3/CD28+LPS组[(29.4±1.6)%,P〈0.01];2组Foxp3平均荧光强度分别为95±9、140±18,差异有统计学意义(P〈0.01)。同时,抗CD3/CD28+LPS+血必净组IFN-γ分泌水平显著高于抗CD3/CD28+LPS组(P〈0.01),IL4则呈相反变化(P〈0.05),抗CD3/CD28+LPS+血必净组IFN-γ/IL-4较对照组升高(P〈0.01);抗CD3/CD28+血必净组IL-17分泌水平较抗CD3/CD28组明显下降(P〈0.05)。结论CD4^+CD25^+Treg细胞活化介导了Th1向Th2功能性极化;血必净对LPS诱导的T淋巴细胞免疫功能有重要调节作用,可促进CD4^+CD25^+Treg细胞凋亡并介导Th2向Th1漂移,从而缓解细胞免疫抑制状态。
Objective To investigate the enhancing effect of Chinese medieine-Xuebijing injection on fipopolysaceharide (LPS)-induced apoptosis of CD4^+ CD25^+ regulatory T cells (Tregs) and polarization of helper T cells (Th). Methods CD4^+ CD25^+ Tregs collected from rat spleen in vitro by immunomagnetie beads assay were divided into the control group, anti-CD3/CD28 group, anti-CD3/CD28 + LPS group, anti-CD3/CD28 + " Xuebijing injection" group and anti-CD3/CD28 + LPS + " Xuebijing injection" group. Tregs apoptosis rate and expression of winged helix transcription factor (Foxp3) in Tregs were detected by flow cytometry on 3rd post culture day. CD4^+ CD25^- T cells were co-cultured with CD4^+ CD25 ^-Tregs (1:1) for 68 hours with canavalin A stimulation. Interferon γ (γ-IFN), interleukin (IL)-4 and IL-17 in su- pernatants, which respectively was secreted by Thl, Th2 and Thl7, were measured by ELISA. Results Tregs apoptosis rate of anti-CD3/CD28 + LPS + " Xuebijing injection" group (45. 1 ± 2.7% ) was significantly higher than that of anti-CD3/CD28 + LPS group (29.4 ±1.6% , P 〈 0.01 ). Meanwhile, Foxp3 expressions in Tregs in above 2 groups were 95 ± 9 and 140 ± 18 respectively, showing statistically significant difference between them( P 〈 0.01 ). γ-IFN levels secreted in anti-CD3/CD28 + LPS + " Xuebijing injec- tion" group were significantly higher than those in anti-CD3/CD28 + LPS group ( P 〈 0. 01 ), while IL-4 levels had an opposite tendency compared with γ-IFN ( P 〈 0.05) , resulting in a marked increase in the ratio of 7-IFN /IL-4 in anti-CD3/CD28 + LPS + " Xuebijing injection" group ( P 〈 0. 01 ). In anti-CD3/ CD28 + " Xuebijing injection" group, IL-17 secretion levels were significantly decreased compared with anti- CD3/CD28 group ( P 〈 0.05). Conclusions Activation of CD4^+ CD25^+ Tregs induced by LPS may mediate Thl shift to Th2 response. " Xuebijing injection" can effec