基于PRRS的粘膜DC程序调控诱导防龋长效抗体效应和机制研究

PRRs sense infection and transmit a series of signals that ultimately lead to the development of immunity. Dendritic cells (DCs) express many PRRs and are remarkably effective at directing T cell immunity. NLRP10 is a NOD-like receptor essential to initiate adaptive immunity by dendritic cells. Recent reports suggest that for the activation of innate immune responses and initiation of adaptive immunity, synergistic effects between two or more PRRs are necessary.Thus, PRRs ligants combination were used as adjuvant to programming the magnitude and persistence of antibody responses to anti-caries vaccine . Firstly, the combinations of NLRP10 and TLRs were selected according to the level of cytokine. Next, nanoparticles were constructed through wrapping NLRP10, TLRs ligants and anti-caries vaccine with chitosan, immunogenic characterization and protection against Streptococcus mutans infection of the nanoparticles were determined by oral or nasal immunization. Ultimately the influence of gene expression on DC and its cellular regulation of T cells were analyzed, cellular components and microenvironment of local mucosa-associated lymphoid tissue were also discussed to explore the possible mechanism ofNLRP10ligant, NLRP/TLRs ligants in enhancing the effect of mucosal immunity by anti-caries Vaccine.

DC表达的PRRs是固有免疫直接识别感染和疫苗，激活适应性免疫关键分子。以PRRs信号系统为基础的PRRs配体可促进DC成熟诱导获得性免疫反应。NLRP10不仅在连接固有免疫和获得性免疫中发挥重要，且调控获得性免疫强度及类型。因此，本课题以PRRs为切入点，促进粘膜DC成熟并调控DC诱导防龋长效抗体效应。首先，以调控DC诱导Th2和TFH免疫类型为标准筛选最佳NLRP10/TLRs配体组合，确定其对DC成熟及DC调控T细胞反应类型的影响。其次，以壳聚糖包裹NLRP10配体、TLRs配体及防龋疫苗成纳米微粒，检测其经粘膜免疫诱导特异性抗体水平、类型与强度，评价防龋保护能力。最后，分析NLRP10配体，NLRP10/TLRs配体组合对DC基因表达及T细胞调节的影响，对粘膜相关淋巴组织的细胞组成与微环境的影响,系统地探讨其增强防龋疫苗粘膜免疫长效抗体效应的分子机制。

本项目针对DC科程序性调控T细胞反应类型特性，以Th2免疫反应类型为出发点，筛选能协同诱导DC 活化Th2细胞因子的NLRn/TLRs配体组合，并探索筛选到的CS/Fimh组合协同增强防龋疫苗免疫效能及相关机制。本项目以项目任务书为指导原则和基础，成功构建NLRP10配体原核表达质粒，纯化制备NLRP10配体，作为新型防龋疫苗佐剂分子。筛选出的NLRP3/TLR4配体组合诱导活化树突状细胞向DC2分化，促进其Th2细胞因子分泌。壳聚糖/Fimh促进防龋疫苗Th2型免疫反应增强其粘膜免疫特异性抗体水平，对定菌鼠具有龋齿保护效应。壳聚糖/Fimh免疫佐剂效应与其活化DC表面TLR4表达，促进DC摄取抗原以及促进T细胞增殖和分化相关。.本项目截止结题日发表标注项目基金号的SCI论文5篇，培养2名博士，3名研究生。专利申请和后续SCI论文的发表正在进行中。