乳杆菌肽聚糖对β-乳球蛋白致敏小鼠脾细胞Th1/Th2及Treg/Th17失衡的体外影响

Effect of whole peptidoglycan from lactobacilli on the imbalance of Th1/Th2 and Treg/Th17 in lymphocyte of bovine β-Lactoglobulin-sensitized mice in vitro

摘要:

【目的】观察嗜酸乳杆菌完整肽聚糖(Whole peptidoglycan，WPG)对致敏脾淋巴细胞Th1/Th2及Treg/Th17平衡的体外调节作用。【方法】 通过腹腔注射β-乳球蛋白(β-Lg)建立BALB/c小鼠牛乳过敏模型。造模成功后，分离致敏小鼠的脾淋巴细胞并分别与不同剂量的WPG共同孵育，酶联免疫法检测细胞上清液中抗体(总IgE和特异性IgE)，Th1/Th2及Treg/Th17相关细胞因子(IFN-γ，IL-4，TGF-β，IL-17)水平，流式细胞术检测脾淋巴细胞中CD3+、CD4+和CD8+的百分含量，荧光定量PCR法检测过敏小鼠脾细胞中Th1/Th2及Treg/Th17相关转录因子T-bet、GATA-3、Foxp3和RORγt mRNA的表达量。【结果】WPG体外刺激致敏脾细胞后可显著抑制IgE的产生，上调CD3+、CD4+细胞数及CD4+/CD8+比值，下调Th2型因子(IL-4，GATA-3 mRNA)和Th17型因子(IL-17，RORγt mRNA)的表达，且与过敏组相比，中、高剂量WPG的作用效果显著(P<0.05)；另外，WPG体外作用还上调了Th1型因子(IFN-γ，T-bet mRNA)及Treg型因子(TGF-β，Foxp3 mRNA)的表达，且具有剂量依赖性。【结论】嗜酸乳杆菌WPG体外刺激可有效纠正致敏脾淋巴细胞的Th1/Th2及Treg/Th17失衡。

Abstract:

[Objective] Aim of this study was to investigate the effect of whole peptidoglycan (WPG) from Lactobacillus acidophilus on regulating Th1/Th2 and Treg/Th17 balance in sensitized splenocytes. [Methods] BALB/c mice were intraperitoneally injected with β-Lactoglobulin (β-Lg), the sensitized splenocytes were stimulated in vitro with different doses of WPG. Supernatants were collected and measured total IgE and β-Lg-specific IgE, Th1/Th2 and Treg/Th17 related cytokines (IFN-γ, IL-4, TGF-β, IL-17) production by ELISA assay; the percentage of CD3+, CD4+, CD8+ subgroups in spleen cells were measured by flow cytometry, and the levels of T-bet, GATA-3, Foxp3 and RORγt mRNA were measured by RT-PCR. [Results] Compared with the allergy group, treatment with medium and high dose of WPG significantly decreased IL-17, RORγt mRNA response. In addition, the numbers of CD3+ and CD4+ cells and the ratio of the secretion of total IgE and β-Lg-specific IgE, Th2-type (IL-4, GATA-3 mRNA) and Th17-type (CD4+/CD8+), Th1-type (IFN-γ, T-bet mRNA) and Treg-type (TGF-β, Foxp3 mRNA) response were increased in the splenocytes stimulated with WPG in a dose manner. [Conclusion] Treatment with WPG from Lactobacillus acidophilus could regulate the imbalance of Th1/Th2 and Treg/Th17 in allergic spleen cells.