NF-κB信号通路调控对粪肠球菌脂磷壁酸刺激下巨噬细胞PD-L1表达的影响  

The effect of NF-κB signaling pathway regulation on PD-L1 expression of Enterococcus faecalis LTA-stimulated macrophages

作　　者：杨艳玲 刘润泽 孙青 范伟[1,2] YANG Yanling;LIU Runze;SUN Qing;FAN Wei(State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration,Key Laboratory of Oral Biomedicine Ministry of Education,Hubei Key Laboratory of Stomatology,School&Hospital of Stomatology,Wuhan University,Wuhan 430079,China)

机构地区：[1]武汉大学口腔医学院口颌系统重建和再生全国重点实验室,口腔生物医学教育部重点实验室,口腔医学湖北省重点实验室,武汉大学口腔医(学)院,湖北武汉430079 [2]武汉大学口腔医院牙体牙髓二科,湖北武汉430079

出　　处：《口腔医学》2024年第7期481-486,共6页Stomatology

基　　金：国家自然科学基金(82270968)。

摘　　要：目的 探讨粪肠球菌脂磷壁酸(lipoteichoic acid, LTA)对巨噬细胞免疫检查点——细胞程序性死亡蛋白配体1(programmed cell death protein ligand 1,PD-L1)表达的影响及调控机制。方法 用不同浓度LTA刺激小鼠单核巨噬细胞系(RAW264.7)建立体外模型,利用流式细胞术、qRT-PCR、蛋白免疫印迹、细胞免疫荧光检测PD-L1表达与核因子κB(nuclear factor kappa-B,NF-κB)p65磷酸化水平;NF-κB通路抑制剂BAY 11-7082预处理巨噬细胞,通过以上方法进一步检测PD-L1、p65磷酸化表达变化。结果 LTA可明显诱导RAW264.7细胞中PD-L1表达,提高p65磷酸化水平(P<0.05);抑制NF-κB信号通路后,p65磷酸化水平明显降低,同时PD-L1表达减少(P<0.05)。结论 LTA可促进PD-L1在巨噬细胞中的表达,该过程受到NF-κB信号通路的调控,为进一步理解慢性根尖周炎发病机制及其治疗提供了新思路。Objective To investigate the effect of Enterococcus faecalis(E. faecalis) lipoteichoic acid(LTA) on the expression of the macrophage immune checkpoint-programmed cell death protein ligand 1(PD-L1) and explore the possible regulatory mechanisms. Methods In vitro model was established by stimulating mouse monocyte macrophage cell line(RAW264.7) with different concentrations of E. faecalis LTA. PD-L1 expression and nuclear factor kappa-B(NF-κB) p65 phosphorylation level were detected using flow cytometry, quantitative real-time polymerase chain reaction(qRT-PCR), Western blot and cellular immunofluorescence. Macrophages were pretreated with the NF-κB signaling pathway inhibitor BAY 11-7082, then the expression of PD-L1 and p65 phosphorylation level were detected by the above methods. Results LTA induced PD-L1 expression in RAW264.7 cells, and p65 phosphorylation level increased(P<0.05). Inhibition of the NF-κB signaling pathway could reduce p65 phosphorylation level, simultaneously reducing the expression of PD-L1 on LTA-stimulated RAW264.7 cells(P<0.05). Conclusion E. faecalis LTA can promote the PD-L1 expression of macrophages and this process is regulated by the NF-κB signaling pathway, which provides further insights into the occurrence and treatment of chronic periapical inflammation.

关 键 词：粪肠球菌 脂磷壁酸 免疫检查点 NF-ΚB 

分 类 号：R781.3[医药卫生—口腔医学]