TGFbeta Blockade in MART TCR-Engineered T Cell Melanoma Immunotherapy in Man

描述(由申请人提供)：对癌症免疫学的理解的提高使临床翻译有了显著的进步。在转移性黑色素瘤患者中使用T细胞受体(TCR)工程T淋巴细胞进行过继细胞转移治疗，其他组和我们也观察到了戏剧性的临床反应。这些应答率超过50%，然而，根据我们的经验，患者最终会复发。我们假设，当这些高度激活和细胞毒性的T淋巴细胞进入免疫抑制的肿瘤微环境时，随着时间的推移，会失去它们的效应功能。肿瘤分泌的转化生长因子是肿瘤微环境免疫抑制特性的主要贡献者。我们推测，将显性负性转化生长因子受体II(DnTFRII)整合到用于转导患者T淋巴细胞的MART-1 TCR逆转录病毒载体中，将使这些细胞对转化生长因子不敏感，从而增强其在黑色素瘤微环境中的效应功能。我们建议在转移性黑色素瘤患者的临床研究中验证这一假设，其中两组MART-1TCR转基因T细胞共输注：一组逆转录病毒转导MART-1TCR，另一组转导相同的TCR和dnTGF1RII。第一个载体(GMP级)已经在手，第二个载体已经进行了预临床测试，将在印第安纳大学国家病毒生产设施(IU VPF)生产。这两个群体的工程化T细胞将在淋巴去除调节方案后重新注入患者体内。过继转移的细胞将在体内通过系统注射白介素2和MART-126-35多肽冲击的树突状细胞疫苗来支持。在这一阶段的临床试验中，主要终点是安全性和可行性；次要终点是研究两个转基因细胞群体的差异持久性，并分析它们的关键免疫学特征；第三终点将是临床反应。我们的具体目标是：1)在I期试验中，评估转移性黑色素瘤患者过继转移MART-1 TCR/dnTGF？RII工程T细胞的安全性、持久性和临床疗效。2)评估与临床反应程度相关的关键免疫学终点。我们将在指定的时间点收集和分析活检组织中的外周血液和肿瘤浸润性淋巴细胞，进行数量、免疫表型和功能分析。我们在加州大学洛杉矶分校有MART-1 TCR临床试验经验的团队了解到，一个关键问题是缺乏长期特定的T细胞持久性和功能。本提案将直接解决这一问题，目标是实现持续的临床反应。

DESCRIPTION (provided by applicant): An improved understanding of cancer immunology has allowed significant advances in clinical translation. Dramatic clinical responses have been observed by other groups and ours with adoptive cell transfer therapy using T cell receptor (TCR)-engineered T lymphocytes in patients with metastatic melanoma. These response rates exceed 50%, however, in our experience, patients eventually relapse. We hypothesize that these highly activated and cytotoxic T lymphocytes, when entering an immunosuppressive tumor microenvironment, lose their effector function over time. Tumor secreted TGF¿ is a major contributor to the immunosuppressive properties of the tumor microenvironment. We hypothesize that incorporating a dominant-negative TGF¿ receptor II (dnTGF¿RII) into the MART-1 TCR retroviral vector used to transduce patient T lymphocytes will render these cells insensitive to TGF¿, resulting in an enhancement of their effector function in the melanoma tumor microenvironment. We propose to test this hypothesis in a clinical investigation of patients with metastatic melanoma in which two populations of MART-1 TCR transgenic T cells are co-infused: one population retrovirally transduced with MART-1 TCR and the other population transduced with the same TCR and the dnTGF¿RII. The first vector (GMP-grade) is in hand, and the second vector, already pre-clinically tested, will be manufactured at the Indiana University National Viral Production Facility (IU VPF). These two populations of engineered T cells will be reintroduced into the patient after a lymphodepleting conditioning regimen. The adoptively transferred cells will be supported in vivo by systemic administration of interleukin-2 and MART-126-35 peptide-pulsed dendritic cell vaccines. In this phase I clinical trial, the primary end-points are safety and feasibility; the secondary end-points are the study of differential persistence of the two transgenic cell populations, and the analysis of their key immunological signatures; and the tertiary end point will be clinical response. Our specific aims are: 1) To evaluate, in a phase I trial, the safety, persistence and clinical response of adoptive transfer of MART-1 TCR/dnTGF¿RII engineered T cells in metastatic melanoma patients. 2) To evaluate key immunological end-points that correlate with the degree of clinical responses. We will collect, at defined time points, and analyze peripheral blood and tumor infiltrating lymphocytes from biopsies for number, immunophenotyping, and functional assays. Our group at UCLA, with a MART-1 TCR clinical trial experience, has learned that a critical issue is the lack of long-term specific T cell persistence and function. This present proposal will directly address this problem with the goal of achieving sustained clinical responses.