Building better T cell receptors for targeted immunotherapy

项目摘要/摘要 T细胞受体(TCR)是一类新的免疫治疗药物。TCR的临床试验 基因修饰的T细胞已经表明，对于晚期糖尿病患者，可以获得客观的临床反应 恶性肿瘤。类似的方法也在开发中，用于治疗传染病。然而，还有 关于用于工程T细胞的TCR的性质以及是否自然发生，存在相当大的争论 TCR可以改进。重点一直放在识别天然的高亲和力的TCR上，这些TCR一直是 在临床试验中得到强调。因为T细胞的效力有时可以通过TCR对 除了抗原性外，还努力在免疫治疗中使用为增强抗原亲和力而设计的TCRs。 然而，在一些基因修饰的T细胞试验中，出现了包括死亡在内的不良事件。在一些 病例中，这显然可归因于TCR交叉反应。此外，由于高亲和力会抑制功能和低 亲和力TCR显然是有功能的，认为提高TCR亲和力更适合免疫治疗的假设是 有问题。在这个多PI提案中，我们提出了一个雄心勃勃和创新的方案，以询问和回答如何 建造更好的TCR用于免疫治疗。我们的总体假设是，结构导向设计与 全面的体外和体内功能研究可以用来设计TCRs以改进抗原 识别，同时限制偏离目标的交叉反应。为了实现这一目标，我们将把T细胞生物学和 洛约拉西村实验室的免疫治疗专业知识与TCR结构和生物物理专业知识 巴黎圣母院的贝克实验室。我们还将纳入“2D亲和力”测量和评估的新兴概念 它们与特异性和其他生物物理参数的关系，2D测量将由 埃默里的埃弗沃德实验室。以MART1肿瘤抗原为模型，从临床相关的 DMF5 TCR，我们提出了以下三个目标：1)确定TCR的结构制导操作 结合冲击性抗原识别和体内功能；2)通过迭代产生改进的TCR变体 结构导向设计和生物物理/功能表征的循环，强调以下能力 独立于亲和力的工程师专一性；3)通过应用 从DMF5到一个或多个不相关的MART1特异性TCR的结果。这些目标的完成将导致 更好地了解TCR是如何识别抗原的，以及如何最有效地设计TCR以实现最佳 在免疫治疗中的作用。

Project Summary / Abstract T cell receptors (TCRs) have emerged as a new class of immunological therapeutics. Clinical trials with TCR gene-modified T cells have shown that objective clinical responses can be obtained for patients with advanced malignancies. Similar approaches are in development for treatment of infectious disease. However, there is considerable debate over the nature of the TCR to be used in engineered T cells, and whether naturally occurring TCRs can be improved. Emphasis has been on identifying natural “high affinity” TCRs, and these have been emphasized in clinical trials. As T cell potency can sometimes be strengthened with the affinity of the TCR for antigen, there have also been efforts to use TCRs engineered for enhanced antigen affinity in immunotherapy. However, adverse events, including deaths, have occurred in some trials with gene-modified T cells. In some cases, this is clearly attributable to TCR cross-reactivity. Moreover, as high affinity can curtail function and low affinity TCRs are clearly functional, the presumption that improved TCR affinity is better for immunotherapy is questionable. In this multi-PI proposal, we propose an ambitious and innovative program to ask and answer how to build better TCRs for immunotherapy. Our overall hypothesis is that structure-guided design coupled with comprehensive in vitro and in vivo functional studies can be used to engineer TCRs for improved antigen recognition while limiting off-target cross-reactivity. To achieve this, we will combine the T cell biology and immunotherapy expertise of the Nishimura lab at Loyola with the TCR structure and biophysics expertise of the Baker lab at Notre Dame. We will also incorporate emerging concepts of “2D affinity” measurements and assess how they relate to specificity and other biophysical parameters, with 2D measurements to be performed by the Evavold lab at Emory. Using the MART1 tumor antigen as a model and beginning with the clinically relevant DMF5 TCR, we propose the following three aims: 1) Determine how structure-guided manipulations of TCR binding impact antigen recognition and in vivo function; 2) Generate improved TCR variants through iterative cycles of structure-guided design and biophysical/functional characterization, emphasizing the capacity to engineer specificity independently of affinity; 3) Assess the generalities of the lessons learned by applying the results from DMF5 to one or more unrelated MART1-specific TCRs. The completion of the aims will lead to a better understanding of how TCRs recognize antigen and how to most effectively engineer TCRs for optimal function in immunotherapy.