Regulation of Natural Killer T cell maturation, homeostasis and activation

项目摘要/摘要： 自然杀伤T细胞(Natural Killer T，NKT)是免疫系统中的先天类细胞，能够迅速激活和产生 细胞因子。NKT细胞已被证明在细菌、病毒和真菌感染以及 在自身免疫性疾病中发挥作用；在镰状细胞疾病和哮喘中导致肺组织损伤；以及在 检测和消除恶性细胞。而特定的转录因子和信号分子 已被证明对NKT细胞的早期发育很重要，许多因素需要他们的 外周细胞的成熟、维持和激活尚不清楚。我最近展示了 转录因子heb是NKT细胞发育所必需的，也表明转录调节因子 ID2控制NKT细胞在肺和肝脏等组织中的存活。这项提议将阐明E的作用 蛋白质和ID蛋白在这一重要细胞类型的分化中。我将探索NKT细胞如何对 急性感染与慢性感染及其激活与失能沉默的相关因素。这就做 研究感染期间NKT细胞的激活如何影响其他适应性免疫细胞，即CD8+T细胞。至 为此，我提出了以下目标。目的1：研究Id2和Id3在NKT细胞中的作用 分化以及这些细胞的动态平衡和激活。我目前的数据显示， 调节因子Id2-和Id3-在NKT细胞分化过程中和成熟NKT细胞中相互表达 周围组织。我建议，使用最近生成的Id2和Id3以及Id2和Id3的报道行- 以检测这些转录调控因子如何影响NKT细胞的成熟和激活。目标2： 了解NKT细胞对急性和慢性感染的反应。NKT细胞产生惊人数量的 细胞因子在激活时，以及表现出细胞毒功能。这种激活猝发之后是一种无能 细胞发生凋亡或保持抗增殖能力的阶段。目前尚不清楚这种无能 NKT细胞在慢性感染期间发生时相，或者实际上NKT细胞是否由于持续的 抗原刺激。利用LCMV作为急性和慢性感染的模型，我将检测NKT细胞的反应 持续的抗原刺激。此外，利用微阵列基因表达分析，我建议检查 NKT细胞在感染过程中过渡到无反应阶段时发生的分子变化。 这些研究的结果将有助于理解胸腺和胸腺中NKT细胞的发育 外周组织及其在急性和慢性感染中激活所需的因素。目标3：定义 NKT细胞激活后如何影响CD8+T细胞效应器和记忆的形成。当NKT细胞产生 当多种炎性细胞因子被激活时，这如何影响CD8+效应和记忆T细胞的形成， 在感染期间对炎症环境非常敏感的是什么，是完全未知的。vbl.使用 NKT细胞缺陷小鼠和T细胞受体转基因小鼠，我将检测效应器和记忆性CD8+T细胞 在感染过程中没有NKT细胞的情况下的形成和功能。这些研究将有助于定义 NKT细胞在急性感染中的重要性，并将评估这些细胞如何影响免疫记忆 免疫系统的重要组成部分，用于预防后续感染。这些研究将 对未来的疫苗设计和疗效很重要。

Project Summary/Abstract: Natural Killer T (NKT) cells are innate-like cells of the immune system, capable of swift activation and production of cytokines. NKT cells have been shown to respond during bacterial, viral and fungal infections, as well as playing roles in autoimmune disease; causing damage to lung tissue in sickle cell disease and in asthma; and in the detection and elimination of malignant cells. While specific transcription factors and signaling molecules have been shown to be important for early stage development of NKT cells, many of the factors required for their maturation, maintenance and activation in the periphery remain unknown. I recently showed that the transcription factor HEB is essential for NKT cell development and also showed that the transcriptional regulator Id2 controls survival of NKT cells in tissues such as lung and liver. This proposal will illuminate the role of E proteins and the Id proteins in differentiation of this important cell type. I will explore how NKT cells respond to acute versus chronic infection and the factors associated with their activation versus anergic silencing. I will examine how NKT cell activation during infection affects other adaptive immune cells, namely CD8+ T cells. To this end I propose the following aims. Aim 1: Examine the role of both Id2 and Id3 during NKT cell differentiation and in the homeostasis and activation of these cells. My current data suggest the transcriptional regulators Id2- and Id3- are reciprocally expressed during NKT cell differentiation and in mature NKT cells in peripheral tissues. I propose, using recently generated reporter lines for Id2 and Id3, as well as Id2 and Id3- deficient lines, to examine how these transcriptional regulators impact NKT cell maturation and activation. Aim 2: Understanding NKT cell response to acute and chronic infection. NKT cells produce prodigious quantities of cytokines upon activation, as well as exhibiting cytotoxic function. This activation burst is followed by an anergic phase in which cells undergo apoptosis or remain resistant to proliferation. It is not known whether this anergic phase occurs in NKT cells during chronic infection or indeed whether NKT cells retain activity due to continual antigen stimulation. Using LCMV as a model of acute and chronic infection, I will examine the NKT cell response to persistent antigen stimulation. Furthermore, using microarray gene-expression analysis, I propose to examine the molecular changes that occur in NKT cells as they transition through the unresponsive phase during infection. The results from these studies will be useful in understanding development of NKT cells in the thymus and peripheral tissues as well as the factors required for their activation in acute and chronic infection. Aim 3: Define how NKT cells affect CD8+ T cell effector and memory formation upon activation. While NKT cells produce numerous inflammatory cytokines when activated, how this affects CD8+ effector and memory T cell formation, which are exquisitely sensitive to the inflammatory environment during infection, is completely unknown. Using NKT cell-deficient mice and T cell receptor-transgenic mice, I will examine effector and memory CD8+ T cell formation and function in the absence of NKT cells during infection. These studies will help to define the importance of NKT cells in acute infection and will assess how these cells influence immunological memory, an essential component of the immune system, required for protection from subsequent infection. These studies will be important for future vaccine design and efficacy.