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，随着耐多药菌株的增加，一种有效的 疫苗解决方案势在必行。合成亚单位疫苗，不含活细菌，目前 通过为免疫功能低下的个体提供更安全的选择，获得了比减毒疫苗更多的优势 并且能够适应快速、可扩展和可重现的生产。亚基疫苗目前正在 为结核分枝杆菌(Mtb)开发的使用多肽或蛋白质抗原，这些抗原针对MHC限制性 传统的T细胞，忽视了结核分枝杆菌脂类抗原作为疫苗候选的潜力。分枝杆菌脂类 由第1组CD1(CD1a、b、c)和第2组CD1d呈递给同源T细胞。组1 CD1-受限T细胞 可以在结核病患者中识别细胞，并已被证明有助于保护性免疫。 结核分枝杆菌感染。为了进一步研究第1组CD1限制性Mtb反应，我们先前创建了CD1 表达转基因小鼠(HCD1Tg)和CD1b限制性T细胞受体转基因T细胞(DN1Tg)特异性 主要为结核分枝杆菌脂类抗原霉菌酸(MA)。自那以后，我们已经证明DN1 T细胞可以被激活 体内接种载MA纳米粒(NP)。我们用MA-NP免疫hCD1Tg-DN1小鼠 以产生记忆DN1 T细胞。通过转录组分析，我们确定了记忆DN1 T细胞 与T滤泡辅助细胞(TFH)最为相似。在这项提案中，我们将评估两个关键TFH小区 Bcl6和PD-1分子是记忆DN1 T细胞分化所必需的。我们还将验证调查结果 在使用单细胞测序的多克隆环境中。最后，我们将测试内存DN1 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 CD1限制T细胞分化的决定因素及其在结核分枝杆菌感染中的作用 朝着创造一种基于脂质的结核分枝杆菌疫苗又近了一步。

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.