Role of CD8+ T Cells in Innate Immune Responses

描述（由申请人提供）：该提案旨在了解CD8+ T细胞的发育、快速功能和定位，CD8+ T细胞在细菌感染期间缺乏同源抗原的情况下作出反应，假设CD8+ T细胞是早期先天产生ifn - γ的重要贡献者。具体目的是：1 .分析记忆性CD8+ T细胞与NK细胞在单核增生李斯特菌（Listeria monocytogenes， LM）感染期间的存活、定位和保护能力。在这个目的中，我们将剖析NK细胞和记忆CD8+ T细胞以非抗原特异性方式响应LM的保护能力差异。我们将使用免疫细胞化学来分析LM感染目标器官内转移细胞的应答群体的位置。此外，使用免疫细胞化学和流式细胞术检测记忆性CD8+ T和NK细胞在LM应答后的存活能力。II：确定CD8+ T细胞在辅助CD4+ T细胞极化中的作用。我们的数据表明，记忆性CD8+ T细胞快速分泌ifn - γ而不依赖同源抗原，因此在先天免疫反应中发挥重要作用，这是通过分泌细胞因子促进TH1发育所必需的。我们现在将直接测试CD8+ T细胞和NK细胞通过分泌ifn - γ来影响TH1发育的能力，使用共转移协议来分析CD4+ T细胞对病原体的反应的极化。III：分析IL-12和IL-18对初始和效应/记忆CD8+ T细胞的影响。在这个目标的第一部分，我们将确定哪些细胞因子（如果有的话）是必需的，以便在初始CD8+ T细胞转变为启动效应细胞期间建立IL-12/IL-18反应性。在本研究的第二部分，我们将使用微阵列分析和实时RT-PCR来确定通过IL-12和IL-18受体信号传导的功能结果，并将其与通过TCR信号传导进行比较。这些研究将进一步加深我们对CD8+ T细胞介导的病原体的先天免疫反应的理解，使我们能够更好地对抗传染病。

DESCRIPTION (provided by applicant): This proposal is aimed at understanding the development, rapid function, and localization of CD8+ T cells that respond in the absence of cognate antigen during bacterial infections, with the hypothesis that CD8+ T cells are important contributors to the early, innate production of IFN-gamma. The specific aims are: I: To analyze the survival, localization and protective ability of memory CD8+ T cells vs. NK cells during a Listeria monocytogenes (LM) infection. In this aim we will dissect the differences in protective ability between NK and memory CD8+ T cells responding to LM in a non-antigen specific fashion. We will use immunocytochemistry to analyze the location of the responding populations of transferred cells within the organs targeted by LM infection. In addition, the ability of memory CD8+ T and NK cells to survive after responding to LM will be measured using immunocytochemistry and flow cytometry. II: To determine the role of CD8+ T cells in aiding in the polarization of CD4+ T cells. Our data shows that memory CD8+ T cells rapidly secrete IFN-gamma independent of cognate antigen and thus play an important role in the innate immune response, which is essential in promoting TH1 development through the secretion of cytokines. We will now directly test the ability of CD8+ T cells and NK cells to influence TH1 development by secreting IFN-gamma using co-transfer protocols to analyze the polarization of CD4+ T cells in response to pathogens. III: To analyze the effects of IL-12 and IL-18 on naive and effector/memory CD8+ T cells. In the first part of this aim, we will determine which cytokines, if any, are required in order to establish IL-12/IL-18 responsiveness during the transition of naive CD8+ T cells into primed, effector cells. In the second part of the aim, we will determine the functional outcomes of signaling through the IL-12 and IL-18 receptors and compare that with signaling through the TCR using microarray analysis and real-time RT-PCR. These studies will further our understanding of innate immune responses to pathogens mediated by CD8+ T cells and allow us to better combat infectious diseases.