【作者】 马倩茹；

【导师】 顾宗江； 张学光；

【作者基本信息】 苏州大学 ， 免疫学， 2006， 硕士

【摘要】 Toll样受体(TLR)是固有性免疫应答中的重要成分，不但在感染性免疫中发挥重要作用，而且参与了肿瘤的免疫应答和免疫逃逸过程，TLR家族中受到广泛关注的是TLR4分子。树突状细胞(DC)作为机体免疫应答的始动者，在对多种疾病应答中，尤其是在对肿瘤的免疫应答中发挥了不可替代的作用。已有研究表明多种因素可以影响单核细胞及树突状细胞上TLR4的表达，但共刺激分子CD40和4-1BB对TLR4表达的影响尚未见报道。本研究旨在通过激活DC或单核细胞上CD40或4-1BB分子后，观察TLR4分子表达的变化，以期为肿瘤免疫治疗提供新的方法与思路。 1．4-1BB信号对小鼠树突状细胞TLR4表达的调节 目的：探讨激发型小鼠4-1BB(CD137)单克隆抗体2A对小鼠骨髓来源未成熟DC(imDC)及树突状细胞株DC2.4表面TLR4表达的调节。方法：在imDC中加入不同剂量2A(联合兔抗大鼠IgG-Fc段抗体，CL)、LPS、2A(+CL)与LPS联合后作用6h，流式细胞术(FCM)检测TLR4表达；或在以上处理因素作用后不同时相(0h、3h、6h、12h、24h)，以及先用LPS刺激imDC 6h再加入2A(+CL)作用6h后，以FCM检测imDC表面TLR4表达。结果：LPS可下调imDC上TLR4的表达，作用可维持24h。单独使用2A无明显效应，但与CL联合后2A可使imDC上调TLR4分子的表达，作用可维持12h。2A(+CL)与LPS联合作用仍可使imDC上调表达TLR4分子。先用LPS预处理imDC6h再加入2A作用6h，2A仍可拮抗LPS的下调作用。在树突状细胞株DC2.4细胞表面也得到相似的结果。结论：4-1BB信号可上调小鼠骨髓来源未成熟DC和树突状细胞株DC2.4表面TLR4的表达，上调效应具有时间和剂量依赖性，并可拮抗LPS介导的TLR4下调效应。 2．CD40信号对人单核细胞和树突状细胞TLR4表达的调节 目的：探讨人激发型CD40单克隆抗体5C11对人单核细胞和树突状细胞TLR4更多还原

【Abstract】 Toll like receptors (TLRs), the most important part in innate immunity, not only play a vital role in infectious diseases, but also have roles in immune responses to tumor and its sneaking. TLR4 has been intensively reported to participate in tumor immunity. Dendritic cells(DCs), as a primary promoter for immune responses, play an important role in many diseases, especially in tumor immunity. There have been many reports on the regulation of TLR4 by factors on monocytes and dendritic cells, but no reports about the regulation by the co-stimulator CD40 or 4-1BB.Therefor, this study was to investigate the expression of TLR4 after activating CD40 or 4-1BB on dendritic cell and monocytes.1. 4-1BB signal mediate the regulation of TLR4 expression on mouse dendritic cellsObjective: To study the regulatory effects of agonist 4-1BB (CD137) monoclonal antibody 2A on TLR4 expression in murine bone marrow derived dendritic cells (imDC) and in a murine DC cell line DC2.4. Methods: Flow cytometry was used to investigate the TLR4 expression on DCs under these conditions: different doses of 2A, LPS, 2A combined with LPS or addition of 2A after pre-stimulation of DCs by LPS. Results: LPS could down-regulate TLR4 expression on DCs, and the down-regulatory effect of LPS was maintained for 24 hours. On the contrary, 2A could up-regulate TLR4 expression on DCs, and this effect of 2A was maintained for 12 hours. Moreover, 2A could inhibit the down-regulatory effect of LPS on TLR4 expression. When DCs were stimulated by 2A after LPS pre-stimulation, 2A could still up-regulate TLR4 expression on DCs. We obtained the similar results both on BMDC and DC2.4 cell line. Conclusion: 4-1BB signal could up-regulate the expression of TLR4 on dendritic cell.2. The study on the role of CD40 signal in regulation of TLR4 expression on human更多还原