Development of a novel platform for the discovery of antigen-specific TCRs

开发用于发现抗原特异性 TCR 的新平台

• 批准号: 10434805
• 负责人: Christopher Seet
• 金额: $ 19.69万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10434805
• 关键词: Address; Adoptive Cell Transfers; Adoptive Immunotherapy; Affinity; Antigen Presentation; Antigens; Autoantigens; Autologous; Baltimore; Binding; Biological; Biological Assay; Blood; CD8-Positive T-Lymphocytes; CTAG1 gene; Clinical; Clone Cells; Cloning; Collaborations; Detection; Development; Disease; Economics; Engineering; Epitopes; Face; Frequencies; Gays; Generations; Goals; HLA-A gene; Haplotypes; Hematologic Neoplasms; Hematology; Hematopoietic stem cells; Human; Immunotherapy; In Vitro; K-Series Research Career Programs; Lead; Logistics; MART-1 Tumor Antigen; Malignant neoplasm of prostate; Mentors; Mentorship; Methods; Modeling; Molecular; Mutation; Nature; Normal tissue morphology; Oncology; Organoids; Outcome; Outcome Study; Patients; Physicians; Privatization; Production; Property; Prostate; Prostate Cancer therapy; Publishing; Reproducibility; Research; Research Proposals; Sampling; Scientist; Series; Source; Specific qualifier value; Specificity; System; T cell differentiation; T cell regulation; T-Cell Receptor; T-Lymphocyte; T-cell receptor repertoire; Technology; Therapeutic; Thymus Gland; Training Support; Transgenes; Tumor Antigens; Umbilical Cord Blood; Validation; Work; antigen-specific T cells; base; cancer immunotherapy; cancer therapy; career; cell mediated immune response; clinical development; clinically translatable; cross reactivity; directed differentiation; engineered stem cells; hematopoietic stem cell differentiation; in vivo Model; instructor; interest; malignant breast neoplasm; neoantigens; new technology; novel; novel strategies; patient population; patient subsets; peripheral blood; peripheral tolerance; pre-clinical; prediction algorithm; reconstitution; success; tumor

PROJECT SUMMARY As a Clinical Instructor in Hematology/Oncology, my career goal is to become an independent physician scientist with a scientific focus on developing new approaches to cancer immunotherapy. This K award period will provide the critical training and support to achieve this goal. This research proposal extends from published work I developed under the mentorship of Dr. Gay Crooks over the past two years. Our interest in the molecular regulation of T cell differentiation from hematopoietic stem and progenitor cells (HSPCs) led us to the discovery that an “artificial thymic organoid” (ATO) culture system permits in vitro thymic-like differentiation of human HSPCs to fully mature human T cells in a robust and highly reproducible manner. This finding was significant in that prior strategies to direct in vitro T cell differentiation from human HSPCs were largely unable to support the generation of functional T cells. We found that ATOs supported the differentiation of cord blood (CB) HSPCs to CD8+ T cells with a highly diverse T cell receptor (TCR) repertoire comparable to that of naïve T cells from the thymus or blood; and further demonstrated that HSPCs engineered with a TCR specific for a tumor-associated antigen efficiently generated mature, tumor-specific T cells in ATOs (Seet et al., Nature Methods, 2017). The focus of this proposal is to exploit a unique property of the ATO system for the de novo discovery of high affinity antigen specific TCRs for cancer immunotherapy. TCR-directed adoptive cell immunotherapy currently relies on the labor-intensive identification from patient samples of TCRs specific to “public” tumor- associated antigens. However, as many public tumor antigens are non-mutated self-antigens, T cells expressing high affinity TCRs against these targets are typically deleted in the thymus during negative selection, ultimately resulting in the isolation of low affinity TCRs from patient samples. We hypothesize that T cells generated in vitro in ATOs are not subject to negative selection, and thus may present a unique source of high affinity tumor antigen specific TCRs for immunotherapy. In this proposal, I will develop a novel ATO-based platform for the discovery of antigen specific TCRs against public tumor antigens; characterize the nature of ATO-derived TCRs relative to those isolated from peripheral blood; and finally apply these methods to the proof-of-concept capture and preclinical validation of TCRs reactive to prostate cancer specific antigens, a disease in which the identification of tumor-specific TCRs from patients has thus far proved challenging. This is an ambitious project, but one in which the chances of success are maximized through collaboration with the labs of my mentor Dr. Gay Crooks, co-mentor Dr. Owen Witte at UCLA, and Dr. David Baltimore at Caltech. Development of a new technology for rapidly identifying high-affinity TCRs against public tumor antigens would be a significant contribution to the field of immunotherapy research, lead to clinically translatable outcomes, and open promising avenues of further independent research.

项目总结 作为一名血液学/肿瘤学临床讲师，我的职业目标是成为一名独立的医生 科学家，致力于开发癌症免疫治疗的新方法。这个K奖励期 将为实现这一目标提供关键的培训和支持。 这项研究提案是从我在盖伊·克鲁克斯博士的指导下开发的已发表的工作扩展而来的 在过去两年里。我们对造血T细胞分化的分子调控感兴趣 干细胞和祖细胞(HSPC)使我们发现一种“人工胸腺器官”(ATO)培养 该系统允许体外向胸腺样分化的人HSPC向完全成熟的人T细胞 和高度可重复性的方式。这一发现在先前指导体外T细胞策略中具有重要意义 人HSPC的分化在很大程度上不能支持功能性T细胞的产生。我们 发现ATOS支持脐血HSPC向CD8+T细胞分化，具有高度多样性 T细胞受体(TCR)谱系可与胸腺或血液中的原始T细胞相媲美； 证明用针对肿瘤相关抗原的TCR基因工程的HSPC有效地产生 ATOS中成熟的肿瘤特异性T细胞(见等人，自然方法，2017)。 这项提议的重点是利用ATO系统的独特性质从头发现 用于肿瘤免疫治疗的高亲和力抗原特异性TCRs。TCR导向的过继细胞免疫治疗 目前依赖于从患者样本中识别出专用于“公共”肿瘤的TCR-- 相关抗原。然而，由于许多公共肿瘤抗原是非突变的自身抗原，T细胞 在阴性期间，针对这些靶点表达的高亲和力TCR通常在胸腺中被删除 最终从患者样本中分离出低亲和力的TCR。我们假设T 在ATOS中体外产生的细胞不受负选择的影响，因此可能是一个独特的来源 高亲和力肿瘤抗原特异性TCRs用于免疫治疗。在这份提案中，我将开发一种基于ATO的新型 发现针对公共肿瘤抗原的抗原特异性TCR的平台；表征 ATO来源的TCR与从外周血中分离的TCR进行比较；最后将这些方法应用于 对前列腺癌特异性抗原反应的TCR的概念验证捕获和临床前验证 到目前为止，从患者身上识别肿瘤特异性TCR是一种具有挑战性的疾病。 这是一个雄心勃勃的项目，但通过合作最大限度地增加了成功的机会 我的导师盖伊·克鲁克斯博士、加州大学洛杉矶分校的共同导师欧文·维特博士和大卫·巴尔的摩博士的实验室 加州理工学院。一种快速鉴定抗公共肿瘤高亲和力TCR的新技术 抗原将对免疫治疗领域的研究做出重大贡献，导致临床 可翻译的结果，并为进一步的独立研究开辟了有希望的途径。