Determinants of antigen specific CD4 T cell function in tuberculosis

该提案提出了一个以抗原研究为重点的五年研究职业发展计划。 结核病中的特定CD4T细胞，长期目标是揭示有关免疫的新信息 预防结核病，并为这种疾病开发有效的新疫苗提供信息。候选人是 现任明尼苏达大学(UMN)传染病学部医学助理教授 疾病。概述的建议建立在候选人之前的经验基础上，通过添加以下新领域 在高级T细胞免疫学、面向患者的国际合作研究和人类 免疫学和单细胞转录学。培训目标由以下导师团队代表 马克·詹金斯和大卫·布尔威尔，以及UMN的其他主要合作者。拟议的试验和 教学工作将使应聘者具备一套独特的跨学科技能，这将使他 过渡到独立，成为一名专注于结核病免疫学的内科科学家。 更好地了解控制结核病患者CD4T细胞功能的因素有助于指导 开发更有可能引起对结核病的保护性免疫的候选疫苗。它正在成为 更清楚的是，干扰素-g的分泌只是结核病患者CD4T细胞的一种保护功能。另一个关键效应器 结核病中CD4T细胞的机制仍在确定中，这些免疫功能的决定因素 仍有待充分研究。这一特定项目的总体科学目标是 CD4T细胞在感染部位的功能，并定义抗原可用性和T细胞受体(TCR)如何- 表位亲和力决定了这些功能。这一建议的前提是CD4T细胞在 结核感染的部位由靶向结核分枝杆菌抗原的特性决定。中心假设是 1)针对中等丰度的Mtb抗原，亲和力较低的TCRs的CD4T细胞有更多 多样和优越的功能，以及2)感染部位的抗原特异性CD4T细胞发挥关键作用 效应器的功能超出了Th1范式。为了检验这些假设，我们提出了以下目标： 1：确定抗原内在因素如何控制结核病患者的CD4T细胞功能，目标2：确定CD4T细胞的特征 人类结核病感染部位的细胞功能和多样性。为了实现这些目标，创新的方法 建议包括：体内Mtb基因表达的调节，低亲和力TCRs的鉴定，以及 无偏见地鉴定最近在体内接受过TCR刺激的CD4T细胞。通过将这些配对 从人类脑脊液中研究人类T细胞在小鼠模型中的方法 HIV相关性结核脑膜炎，使用单细胞转录图谱，这些研究将表征结核分枝杆菌如何 抗原内源性因素诱导的CD4T细胞群具有不同的功能能力和多样性。这个K08 该项目将指导新的结核病疫苗的开发，并促进候选人向独立的过渡。

This proposal presents a five-year research career development program focused on the study of antigen specific CD4 T cells in tuberculosis (TB), with the long-term goals to reveal new information about immune protection in TB and inform the development of an effective new vaccine for this disease. The candidate is currently an Assistant Professor of Medicine at the University of Minnesota (UMN) in the Division of Infectious Diseases. The outlined proposal builds on the candidate’s previous experience by adding new domains of expertise in advanced T cell immunology, international collaborative patient-oriented research and human immunology, and single cell transcriptomics. The training objectives are represented by the mentorship team of Marc Jenkins and David Boulware, and other key collaborators at UMN. The proposed experimental and didactic work will position the candidate with a unique set of cross-disciplinary skills that will enable his transition to independence as a physician scientist focused on the immunology of TB. A better understanding of the factors that govern CD4 T cell function in TB could help guide the development of vaccine candidates more likely to elicit protective immunity against TB disease. It is becoming clearer that IFN-g secretion is only one protective function of CD4 T cells in TB. The other key effector mechanisms of CD4 T cells in TB are still being defined, and the determinants of these immune functions remain to be fully characterized. The overall scientific objectives of this particular project are to characterize CD4 T cell functions at the site of infection and to define how antigen availability and T cell receptor (TCR)- epitope affinity govern these functions. The premise of this proposal is that effector activity of CD4 T cells at the site of TB infection is determined by characteristics of the Mtb antigen targeted. The central hypotheses are 1) that CD4 T cells with lower affinity TCRs, targeting Mtb antigens with moderate abundance, have more diverse and superior functions, and 2) that antigen specific CD4 T cells at the site of infection perform key effector functions outside the Th1 paradigm. To test these hypotheses, the following aims are proposed: Aim 1: Determine how antigen-intrinsic factors govern CD4 T cell function in TB, and Aim 2: Characterize CD4 T cell function and diversity at the site of human TB infection. To accomplish these aims, innovative approaches are proposed including: modulation of Mtb gene expression in vivo, identification of lower affinity TCRs, and unbiased identification of CD4 T cells that have recently received TCR stimulation in vivo. By pairing these approaches in the mouse model with studies of human T cells from the cerebrospinal fluid of individuals with HIV-associated TB meningitis, using single cell transcriptomic profiling, these studies will characterize how Mtb antigen-intrinsic factors elicit CD4 T cell populations of varying functional capacity and diversity. This K08 project will guide new TB vaccine development and promote the candidate’s transition to independence.