T-cell monitoring and immunotherapy for treating graft-versus-host disease

描述(申请人提供)：造血细胞移植(HCT)是一种潜在的治疗范围广泛的血液系统恶性肿瘤和其他疾病的治疗方法，然而，急性GVHD是限制其使用并导致显著发病率和死亡率的主要并发症。1-3大约一半的急性GVHD患者将患有激素难治性疾病，具有特别高的死亡率，几乎没有治疗选择。由于目前还没有临床试验来前瞻性地识别或治疗类固醇难治性移植物抗宿主病，治疗在很大程度上是经验性的。2我的中心长期目标是将T细胞免疫监测和基于T细胞的免疫疗法的使用和发展结合起来，以改善HCT患者以及最终许多其他患者的预后。在这项申请中，我们提出的工作可以重新定义我们如何理解、诊断和治疗移植物抗宿主病，并对许多其他免疫学疾病产生影响。我们建议应用先进的基于核苷酸测序的方法来识别和追踪引起移植物抗宿主病的T细胞。我们建议证明，这些知识可以用来指导开发和实施改进的监测和新的治疗方法来治疗这些患者。这包括开发免疫抑制T调节细胞来治疗GVHD。我们建议研究GVHD的临床前模型，并测试似乎可以治疗活动和严重GVHD的新型受过教育的捐赠者CD25 Tregs是否可以移植到临床。如果eTregs的表型被澄清，并且我们已经回答了这些细胞在临床相关环境中是否损害移植物抗肿瘤反应和功能的问题，这一点就可以实现。我们预计eTregs将需要产生MHC相互作用，较少依赖IL-2发挥作用，并将防止通过T细胞谱系测序和/或对已知GVHD抗原的反应而识别的GVHD相关T细胞克隆的扩张。我们还建议定义T细胞信号来预测、确认或分层患者的急性移植物抗宿主病。我们建议将流式细胞术和单细胞基因组学结合到这一方法中，最终使临床医生能够在临床决策中加入适应性免疫系统的功能。如果我们证实TCR测序可以用来对激素难治性患者进行风险分层，或者扩展到帮助预测GVHD，我们就可以实现我们的研究目标。此外，如果我们能够确定与GVHD高度相关的T细胞的表型和治疗反应，无论是接受常规HCT的患者还是那些接受Tregs预防或治疗GVHD的患者，这一目标都将实现。作为这项工作的延伸，我们设想了通过整合高通量TCR测序来发现GVHD靶抗原来识别GVHD靶抗原的新方法。这项建议将使科学家和临床从业者能够更好地了解和控制同种免疫，并有望有助于预防或治愈GVHD。

DESCRIPTION (provided by applicant): Hematopoietic cell transplantation (HCT) is a potentially curative therapy for a broad range of hematological malignancies and other disorders, however, acute GVHD is a major complication that limits the use and results in significant morbidity and mortality.1-3 About half of patients with acute GVHD will have steroid refractory disease that carries an especially high mortality with few treatment options. Because there are currently no clinical tests to prospectively identify or treat steroid refractory GVHD, therapy is largely empiric.2 My central long-term goal is to combine the use and development of T cell immune monitoring and T cell based immunotherapy to improve outcomes for HCT patients and, eventually, many other patients. In this application, we propose work that could redefine how we understand, diagnose and treat GVHD with implications for many other immunologic diseases. We propose to apply cutting-edge nucleotide sequencing- based approaches to identify and track T cells causing GVHD. We propose to show that this knowledge can be used to guide the development and implementation of improved monitoring and new therapies to treat these patients. This includes the development of immunosuppressive Tregulatory cells to treat GVHD We propose to study pre-clinical models of GVHD and to test if novel 'educated' donor CD25+ Tregs that appear to treat active and severe GVHD might be translated to the clinic. This will be accomplished if the phenotype of eTregs is clarified and we have answered the question as to whether or not these cells impair graft-versus tumor response and function in clinically relevant settings. We anticipate that eTregs will require MHC interactions to be generated, depend less upon IL-2 to function and will prevent the expansion of GVHD- associated T cell clones identified by T cell repertoire sequencing and/or response to known GVHD antigens. We propose also to defining T cell signatures that predict, confirm or stratify acute GVHD in patients. We propose to integrate flow cytometry and single cell genomics into this approach, advances that could finally allow clinicians to accession the function of the adaptive immune system in making clinical decisions. We will accomplish the goals of our study if we confirm TCR sequencing can be used to risk stratify steroid refractory patients or extended to help predict GVHD. In addition, the aim will be accomplished if we can identify the phenotype and treatment response of T cells highly implicated in GVHD, both for patients undergoing conventional HCT and for those receiving Tregs for the prevention or treatment of GVHD. As an extension of this work, we have conceived of novel approaches to identify GVHD target antigens by integrating high- throughput TCR sequencing for GVHD target antigen discovery. This proposal will allow scientists and clinical practitioners to better understand and control alloimmunity and hopefully help to prevent or cure GVHD.