On the plasticity of Beta-cell antigen recognition by diabetogenic CD8 T cells

项目总结 CD8T细胞在T1D发病机制中起重要作用。它们构成了最丰富的免疫细胞 患者胰岛中的种群呈渗入状态。在T1D的非肥胖糖尿病(NOD)模型中，它们需要 糖尿病的发展。自身反应性T细胞在胰岛中的渗透和滞留严格依赖于 对β细胞抗原的特异性识别。这种自我认识也决定了致糖尿病的CD8 T细胞 β细胞的细胞毒性和最终杀伤力。然而，CD8 T细胞如何识别β-T细胞却知之甚少。 细胞抗原。在过去的十年里，我们使用了新的2D分析来表征T细胞抗原识别 通常，2D亲和力和机械力是确定T细胞的两个定义动力学参数 回应。在目前的方案中，我们将通过以下方式将这些2D方法应用于β细胞抗原识别 并通过单细胞RNA测序阐明其潜在的分子机制。 我们的初步数据显示，致糖尿病的CD8T细胞可以极大地改变自身抗原的亲和力和/或作用力 识别依赖于T细胞的成熟、激活和疾病状态。我们提出了两个具体目标来 验证一个中心假设，即糖尿病原性CD8 T细胞与β细胞自身抗原弱结合以逃避 耐受性机制，但可以上调结合强度，以推动疾病。在具体目标1中，我们将使用我们的2D 方法研究CD8T细胞识别β细胞抗原的亲和力和作用力 糖尿病的症状。在特定目标2中，我们将使用单细胞转录组分析来阐明分子机制。 这不正常地调节了β细胞自身抗原的识别。该项目将产生关键但目前 缺少关于β细胞自身抗原识别的信息，并为新的干预策略提供信息 能够特异性地靶向致糖尿病的CD8 T细胞。

Project summary CD8 T cells play an essential role in T1D pathogenesis. They comprise the most abundant immune cell population in patient islet infiltrates. In the non-obese diabetic (NOD) model of T1D, they are required for diabetes development. The infiltration and retention of autoreactive T cells in islets is strictly dependent on specific recognition of beta-cell antigens. Such self-recognition also determines diabetogenic CD8 T cell’s cytotoxicity and ultimate killing of beta-cells. However, little is known about how CD8+ T cells recognize beta- cell antigens. Over the past decade, we have used novel 2D assays to characterize T cell antigen recognition in general, revealing 2D affinity and mechanical force as two defining kinetics parameters in determining T cell responses. In the current proposal, we will apply these 2D methods to beta-cell antigen recognition by autoimmune CD8 T cells and elucidate the underlying molecular mechanisms by single cell RNA sequencing. Our preliminary data show that diabetogenic CD8 T cells can greatly change affinity and/or force of self-antigen recognition depending on T cell maturation, activation, and disease status. We propose two specific aims to test a central hypothesis that diabetogenic CD8 T cells bind to beta-cell self-antigens weakly to evade tolerance mechanisms but can upregulate bond strength to drive disease. In Specific Aim 1, we will use our 2D methods to characterize affinity and force of beta-cell antigen recognition by CD8 T cells throughout the course of diabetes. In Specific Aim 2, we will use single cell transcriptome analysis to elucidate molecular mechanisms that abnormally regulate beta-cell self-antigen recognition. The project will generate critical yet currently missing information on beta-cell self-antigen recognition and inform novel intervention strategies that are capable of specifically targeting diabetogenic CD8 T cells.