Toll-Like Receptor 4 Signaling in High Mobility Group Box-1 Protein 1 Mediated the Suppression of Regulatory T-Cells.
Toll-Like Receptor 4 Signaling in High Mobility Group Box-1 Protein 1 Mediated the Suppression of Regulatory T-Cells.
复制标题
高迁移率组Box-1蛋白1中的Toll样受体4信号传导介导了调节T细胞的抑制。
DOI：
10.12659/msm.902081
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发表时间：
2017-01-18
期刊：
影响因子：
--
通讯作者：
Wang J
中科院分区：
文献类型：
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作者：
Luo C;Liu H;Wang H;Wang J
Treg细胞在免疫应答的抑制中起核心作用，并且它们的抑制能力可以由toll样受体（TLR）配体调节。然而，TLR配体调节的详细途径仍然未知。本研究旨在评估高迁移率族蛋白B1（HMGB 1）和脂多糖（LPS）通过TLR 4信号转导对Treg细胞的影响。用磁珠活性细胞分选法（MACS）从健康人外周血单个核细胞（PBMC）中分离Treg细胞，用抗TLR 4单克隆抗体封闭，然后与不同浓度的LPS或HMGB 1孵育。采用实时定量聚合酶链反应（qPCR）和酶联免疫吸附试验（ELISA）检测IL-1β、IL-10、IFN-γ和TGF-β基因表达水平，流式细胞术检测LPS和HMGB 1对Treg细胞增殖的影响。Western blotting检测Treg细胞NF-κB的表达。LPS处理后，CD 4 CD 25 Treg细胞表达IL-1β和IL-10明显增加，IFN-γ和TGF-β明显减少。然而，HMGB 1处理导致IL-1β、IL-10、IFN-γ和TGF-β的表达显著降低。LPS处理组Treg细胞明显抑制CD 4 + T细胞增殖，HMGB 1处理组抑制作用减弱。提示HMGB 1和LPS刺激可下调NF-κB p65在细胞质中的表达，上调NF-κB p65在细胞核中的表达，从而调节IL-1β、IL-10、IFN-γ和TGF-β的表达; TLR 4可调节Treg细胞的抑制功能。HMGB 1中的TLR 4信号通过激活NF-κB通路介导Treg细胞的抑制功能。
Treg cells play a central role in the suppression of immune response, and their suppressive capacity can be modulated by toll-like receptor (TLR) ligands. However, the detailed pathway of TLR ligand modulation is still unknown. The present study aimed to evaluate the effect of the high mobility group box-1 protein 1 (HMGB1) and lipopolysaccharide (LPS) on Treg cells through TLR4 signaling. Treg cells were purified from healthy human peripheral blood mononuclear cells (PBMCs) by magnetic-bead activity cell sorting (MACS), blocked by anti-TLR4 monoclonal antibody, and then incubated with different concentration of LPS or HMGB1. The level of gene expression of IL-1β, IL-10, IFN-γ, and TGF-β were detected using quantitative real-time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA), and the proliferation of Treg cells after treating by LPS and HMGB1 was analyzed by flow cytometry. The NF-κB expression in Treg cells was examined by Western blotting. LPS treated CD4 CD25 Treg cells directly increased the expression of IL-1β and IL-10 and decreased the expression of IFN-γ and TGF-β. However, HMGB1 treatment resulted in a marked decreased expression of IL-1β, IL-10, IFN-γ, and TGF-β. The proliferation of CD4+ T cells was significantly inhibited by Treg cells in the LPS treatment group, but weaken in the HMGB1 treatment group. These data suggest that HMGB1 and LPS stimulation could downregulate the expression NF-κB p65 in cytoplasmic proteins and increase the expression in nuclear proteins, thus leading to modulation of IL-1β, IL-10, IFN-γ, and TGF-β expression; moreover, the suppressive function of Treg cells could be regulated by TLR4. TLR4 signaling in HMGB1 mediated the suppressive function of Treg cells through the activation of the NF-κB pathway.