Adoptive immunotherapy after umbilical cord blood transplant

描述(申请人提供)：该研究针对B系急性淋巴细胞白血病(B-ALL)脐带血移植(UCBT)后复发的问题。我们假设，通过过继转移供者来源的白血病特异性T细胞来靶向移植后微小残留病(MRD)，可以减少异基因UCBT后复发的发生率。作为一种在UCBT后可重复产生效应细胞用于过继治疗的策略，我们设计了一种新的嵌合抗原受体(CAR)，命名为CD19RCD28，它将T细胞的抗原特异性重定向到B细胞谱系限制的细胞表面分子CD19。基因修饰的CD19-CAR*细胞毒性T淋巴细胞(CTL)通过嵌合CD28和CD3激活，并以CAR调控的方式杀伤B细胞恶性靶细胞。MDACC的T细胞分离、基因修改和扩增标准操作程序将根据FDA规定的质量控制/保证标准生产临床细胞剂量。在特定目标#1中提出的研究将评估在降低CD19*B-ALL的异基因UCBT治疗强度后，使用三个递增剂量(108/m2-1010/m2)的供者来源的CD19RCD28+HyTK+CTL克隆与寡克隆/多克隆T细胞系进行过继治疗的可行性和安全性。我们假设淋巴去除准备方案将促进被转移T细胞的动态平衡增殖，以及限制抗转基因排斥反应。在特定目标#2中的相关研究集中在利用载体特异性Q-PCR和对连续采集的PBMC样本进行TCR分型分析来描述在三个规定的T细胞剂量水平下转移的克隆与系的持续时间和大小。我们还将评估应用重组人IL-2促进体内转移的T细胞扩增的有效性。在特定目标3中提出的相关研究将评估移植克隆与系的骨髓和淋巴转移，以及移植T细胞在B-ALL MRD这些解剖部位的功能状态。总而言之，所提出的研究结果将促进以CD19特异性T细胞为靶点的UCBT后MRD的发展，以提高B系ALL患者的无病生存率，并证实了将这种方法扩展到更广泛的经HCT治疗的CD19+恶性肿瘤的基本原理。

DESCRIPTION (provided by applicant): The studies address the problem of relapse of B-lineage acute lymphoblastic leukemia (B-ALL) after umbilical cord blood transplant (UCBT). We hypothesize that the incidence of relapse following allogeneic UCBT can be reduced by targeting post-transplant minimal residual disease (MRD) with adoptively transferred donor-derived leukemia-specific T-cells. As a strategy to reproducibly generate effector cells for adoptive therapy after UCBT, we have designed a new chimeric antigen receptor (CAR), designated CD19RCD28, which re-directs the antigen specificity of T cells to the B-cell lineage-restricted cell-surface molecule CD19. Genetically-modified CD19-CAR* cytotoxic T lymphocytes (CTL's) are activated through chimeric CD28 and CD3, and lyse B-cell malignant target cells in a CAR-regulated manner. T-cell isolation, genetic modification, and expansion Standard Operating Procedures at MDACC will manufacture clinical cell doses in accordance with quality control/assurance standards mandated by the FDA. The studies proposed in Specific Aim #1 will evaluate the feasibility and safety of adoptive therapy using three escalating doses (108/m2-1010/m2) of donor-derived CD19RCD28+HyTK+ CTL-clones versus oligoclonal/polyclonal T-cell lines, after reduced intensity allogeneic UCBT for high-risk CD19* B-ALL. We hypothesize that the lymphodepleting preparative regimen will promote homeostatic proliferation of transferred T-cells, as well as, limit anti-transgene rejection responses. The correlative studies in Specific Aim #2 focus on delineating the magnitude and duration of persistence of transferred clones versus lines at the three prescribed T-cell dose levels using vector-specific Q-PCR and TCR spectratyping analyses on serially acquired PBMC specimens. We will also evaluate the utility of administering recombinant human IL-2 for enhancing the expansion of transferred T-cells in vivo. The correlative studies proposed in Specific Aim 3 will evaluate the bone marrow and lymph node trafficking of transferred clones versus lines, and, the functional status of transferred T-cells in these anatomic sites of B-ALL MRD. In aggregate, the results of the studies proposed will facilitate the evolution of targeting post-UCBT MRD with CD19-specific T-cells for enhanced disease-free survival of patients with B-lineage ALL, and substantiate the rationale to expand this approach to a broader array of CD19+ malignancies treated by HCT.