T CELL MATURATION AND LIGAND QUALITY

未能解决传染病以及对抗自身免疫性疾病 疾病往往是由于不适当的，而不是由于不足， 免疫反应。因此，疫苗设计必须能够 操纵诱导的反应类型。我们正在提出一项全面的 分析有助于确定方向的参数， T细胞细胞因子分泌谱。我们将探讨如何 显性/隐蔽性和可用性/亲和性影响决定子 展示，以及抗原呈递模式的方式-- 什么样的菌株，用什么样的细胞因子，通过什么途径--联合收割机 Th 1/Th 2选择。免疫优势与Th 1/Th 2的关系是什么 选择和诱导或保护免受疾病？基于我们之前 有证据表明，决定簇的MHC结合亲和力可以影响T 细胞因子分泌谱，我们将重点介绍抗原的作用 本身我们将调节MHC结合亲和力的决定因素， LACK抗原或利什曼原虫和髓鞘碱性蛋白（MBP），在 以诱导Th 1或Th 2应答来保护小鼠免受L.主要 感染或MBP诱导实验性变态反应性脑脊髓炎（EAE）， 分别MHC结合亲和力、佐剂、 细胞因子环境（包括腺病毒介导的细胞因子基因递送）和 将评估小鼠遗传背景。我们还将解决影响 对T细胞库的这种操纵。来自Vbeta单链 转基因T细胞，对LACK的肽（161-173）具有特异性， 将选择不同的Valpha基因和广泛不同的亲和力 并制备3条表达这些TCR的新转基因链。我们 将决定高亲合力和低亲合力T细胞是否具有 在高和低MHC存在下影响Th 1/Th 2选择的能力- 亲和配体。无论是高亲和力还是低亲和力， 使用免疫镜测定不同的T细胞群 分析，其允许基于T细胞应答的可视化， 不同的CDR 3长度。亚显性免疫特异性T细胞的作用 基于不同的CDR 3长度，在应答内确定一个或多个决定因素。的作用 对MBP 121 -150内的次显性决定簇特异的T细胞 区域，在决定簇扩散期间早期招募，将被研究。 该区域由两个重叠的决定因素组成， 不同的MHC结合亲和力。我们将分析这些 决定簇诱导T细胞与T细胞重叠的共同特异性 细胞的私人或侧翼特异性。这项研究将使我们能够 定义MHC亲和力和TCR亲合力在引导免疫应答中的相对作用。 保护性反应和攻击性反应。

The failure to resolve infectious diseases as well as to fight autoimmune diseases often results from inappropriate, rather than from insufficient, immune responses. Thus, it is critical for vaccine design to be able to manipulate the type of response induced. We are proposing a comprehensive analysis of parameters that contribute to determining the direction of the T cell cytokine secretion profile. We will explore how dominance/crypticity, and availability/affinity affect determinant display, as well as ways in which the mode of antigenic presentation--in what strain, with what cytokines, by what route--combine to influence Th1/Th2 choice. What is the relationship of immunodominance to Th1/Th2 choice and induction or protection from disease? Based on our previous evidence that MHC-binding affinity of the determinant can impact the T cell cytokine secretion profile, we will focus on the role of antigen itself. We will modulate the MHC-binding affinity of determinants of the LACK antigen or Leishmania major and of myelin basic protein (MBP), in order to induce a Th1 or Th2 response to protect mice from L. major infection or MBP-induced experimental allergic encephalomyelitis (EAE), respectively. The relative importance of MHC-binding affinity, adjuvant, cytokine milieu (including adenovirus-mediated cytokine gene delivery) and mouse genetic background will be assessed. We will also address the impact of such manipulations on the T cell repertoire. From Vbeta single chain transgenic T cells, specific for peptide (161-173) of LACK, T cells with different Valpha genes and of widely disparate affinities will be selected and 3 new transgenic chains will be prepared expressing these TCRs. We will determine whether both high avidity and low avidity T cells have the capacity to affect Th1/Th2 choice in the presence of high and low MHC- affinity ligands. Whether high and low affinity, MHC ligands address distinct populations of T cell swill be determined using immunoscope analysis, which allows visualization of the T cell response based on distinct CDR3 lengths. The role of T cells specific for a subdominant determinant within the responses based on distinct CDR3 lengths. The role of T cells specific for a subdominant determinant within the MBP121-150 region, recruited early during determinant spreading, will be studied. This region consists of two overlapping determinants that possess differential MHC-binding affinities. We will analyze whether these determinants induce T cells of overlapping common specificity versus T cells of private or flanking specificity. This study will allow us to define the relative roles of MHC affinity and TCR avidity in steering the response in a protective versus an aggressive direction.