Role of molecular drivers in memory group 1 CD1-restricted T cell differentiation and Mycobacterium tuberculosis infection

项目摘要 结核病仍然是一种严重的全球流行病，随着多重耐药菌株的增加， 疫苗是当务之急。不含活菌的合成亚单位疫苗， 通过为免疫功能低下的个体提供更安全的选择， 并且适合于快速、可规模化和可再现的生产。目前正在研制的亚单位疫苗 针对结核分枝杆菌（Mtb）开发的使用肽或蛋白质抗原，其靶向MHC限制性 传统的T细胞，忽视了Mtb脂质抗原作为疫苗候选物的潜力。分枝杆菌脂质 由第1组CD 1（CD 1a，B，c）和第2组CD 1d呈递给同源T细胞。第1组CD 1限制性T细胞 细胞可以在结核病患者中鉴定，并已显示有助于保护性免疫， 结核病感染。为了进一步研究研究组1 CD 1限制性结核分枝杆菌反应，我们先前创建了CD 1 表达转基因小鼠（hCD 1 Tg）和CD 1b限制性T细胞受体转基因T细胞（DN 1 Tg）特异性 主要的Mtb脂质抗原分枝菌酸（MA）。我们已经证明，DN 1 T细胞可以被激活， 通过用负载有MA的纳米颗粒（NP）接种在体内。我们用MA-NP免疫hCD 1 Tg-DN 1小鼠， 以产生记忆DN 1 T细胞。使用转录组分析，我们确定记忆DN 1 T细胞 最类似于T滤泡辅助细胞（TFH）。在这项建议中，我们将评估两个关键的TFH细胞 分子Bcl 6和PD-1是记忆DN 1 T细胞分化所必需的。我们还将验证调查结果 在多克隆环境中使用单细胞测序。最后，我们将测试记忆DN 1 T细胞是否可以 在结核分枝杆菌感染条件下提供保护。通过这项工作，我们将能够了解独特的 记忆组1 CD 1-限制性T细胞分化的决定因素及其在Mtb感染中的作用 离研制结核分枝杆菌脂质疫苗又近了一步。

Project Summary Tuberculosis remains a serious global epidemic and with the rise of multi-drug resistant strains, an efficacious vaccine solution is imperative. Synthetic subunit vaccines, which do not contain live bacteria, present numerous advantages over attenuated vaccines by offering a safer option for immunocompromised individuals and being amenable to rapid, scalable, and reproducible production. The subunit vaccines currently being developed for Mycobacterium tuberculosis (Mtb) use peptide or protein antigens, which target MHC-restricted conventional T cells, overlooking the potential of Mtb lipid antigens as vaccine candidates. Mycobacterial lipids are presented by group 1 CD1 (CD1a, b, c) and group 2 CD1d to cognate T cells. Group 1 CD1-restricted T cells can be identified in patients with TB and have been shown to contribute to protective immunity against Mtb infection. In order to study further study group 1 CD1-restricted Mtb response, we previously created CD1 expressing transgenic mice (hCD1Tg) and CD1b-restricted T cell receptor transgenic T cells (DN1Tg) specific for the dominant Mtb lipid antigen mycolic acid (MA). We have since showed that DN1 T cells can be activated in vivo by vaccination with nanoparticles (NP) loaded with MA. We immunized hCD1Tg-DN1 mice with MA-NP to generate memory DN1 T cells. Using transcriptome analysis, we then determined that memory DN1 T cells most closely resemble T follicular helper (TFH) cells. In this proposal, we will assess whether two key TFH cell molecules, Bcl6 and PD-1, are necessary for memory DN1 T cell differentiation. We will also validate findings in the polyclonal setting using single cell sequencing. Finally, we will test whether memory DN1 T cell can provide protection in Mtb infection conditions. Through this work, we will be able to understand unique determinants of memory group 1 CD1-restricted T cells differentiation and their role in Mtb infection bringing us a step closer to creating a lipid-based vaccine for Mtb.