Toll样受体增强树突状细胞中腺苷受体A2B亚型的表达及功能  

Toll-like Receptor Signaling Promotes Expression and Function of Adenosine Receptor A2B Subtype in Dendritic Cells

作　　者：周树民[1] 赵嵘[2] 左爱军[3] 

机构地区：[1]天津医科大学第二附属医院检验科,天津300211 [2]天津市人民医院,天津300191 [3]美国南加利福尼亚大学,ca91016

出　　处：《中国生物化学与分子生物学报》2014年第2期163-169,共7页Chinese Journal of Biochemistry and Molecular Biology

摘　　要：树突状细胞(dendritic cell,DC)表面所表达的腺苷受体A2B亚型(ADOR-A2B)可促进DC对辅助性T淋巴细胞(T helper cell,Th)的激活,导致自身免疫性疾病的发生或加重.本文旨在研究作为免疫反应的诱导分子Toll样受体(Toll-like receptors,TLRs)是否可调节ADOR-A2B在DC中的表达并籍此影响其功能.体外诱导小鼠骨髓细胞分化为树突状细胞(BM-DC),以多种TLRs的配体,Pam3csk4、polyIC、LPS及CpG进行干预.提取细胞总RNA,real-time PCR测定ador-a2a、ador-a2b的表达;放射性配体结合实验测定BM-DC对3H-腺苷结合能力的变化.以LPS及选择性ADOR-A2B激动剂BAY 60-6583协同干预BM-DC,ELISA测定培养基中IL-1、IL-6及IL-12的含量.以干预后的BM-DC刺激naive CD4细胞,ELISA测定培养基中IL-17A、IFNγ的含量,荧光抗体染色及流式细胞仪分析检测CD4细胞的分化.结果显示,TLR-4的配体LPS可显著提高BM-DC中ador-a2b的表达及对腺苷的结合能力.BAY 60-6583与LPS相协同可刺激BM-DC分泌多种致炎因子,并增加其诱导CD4细胞向Th1及Th17分化的能力.由此可见,Toll样受体可上调adora2b在DC中的表达,并可籍此增加DC分泌促炎因子的能力及对CD4细胞的刺激作用.The signaling of adenosine receptor A2B subtype （ADOR-A2B） was reported to enhance the proinflammatory function in dendritic cells （DCs） by promoting the secretion of proinflammatoty chemokines/cytokines as well as intensifying the interaction between DCs and effecter T cells. To clarify whether the expression of ador-a2b in DCs is regulated by Toll-like receptors （TLRs） signaling, mouse bone marrow cells derived dendritic cells （BM-DC） were treated with different toll-like receptor ligands ： Pam3csk4, polyIC, LPS and CpG. Total RNA was isolated and the expressions of ador-a2a and a2b in these BM-DCs were determined by real-time qPCR assay. The selective binding capacities of ADOR-A2A and ADOR-A2B to 3H-adenosie in these TLRs ligands treated BM-DCs were also determined. BM-DCs were further treated with LPS and selective ADOR-A2B agonists BAY 60-6583 individually or in the combination, IL-1, IL-6 and IL-12 concentrations in the medium were measured by ELISA. Then the treated BM-DCs were subjected to the interaction with naive CD4 cells. Cytokines production and differentiation toward Thl and Thl7 of the interacted CD4 cells were evaluated by ELISA and flow eytometry analysis, respectively. The result showed that LPS intensively augment ador-a2b expression in BM-DCs, and the binding capacity of LPS treated BM-DCs to adenosine was increased as well. Selective ADOR-A2B agonist BAY 60-6583 showed synergetic effect with LPS on promoting BM-DCs secreting proinflammatory cytokines as well as enhancing the polarization of CD4 cells toward Thl and Thl7 cells. It was concluded that toll-like receptors signaling have the ability of directly upregulating ador-a2b expression in dendritic cells and hence increase its potential of secreting more proinflammatory cytokines and intensifying the interaction with CD4 cells.

关 键 词：树突状细胞 TOLL样受体 腺苷受体 表达 

分 类 号：R392.11[医药卫生—免疫学]