Adoptive immunotherapy after umbilical cord blood transplant

描述（由申请人提供）：该研究针对脐带血移植（UCBT）后b系急性淋巴细胞白血病（B-ALL）复发的问题。我们假设同种异体UCBT后的复发发生率可以通过过继移植供体来源的白血病特异性t细胞靶向移植后最小残留病（MRD）来降低。作为在UCBT后可重复产生效应细胞的策略，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新定向到b细胞谱系限制细胞表面分子CD19。基因修饰的CD19-CAR*细胞毒性T淋巴细胞（CTL's）通过嵌合CD28和CD3被激活，并以car调节的方式裂解b细胞恶性靶细胞。t细胞分离、基因修饰和扩增MDACC的标准操作程序将按照FDA规定的质量控制/保证标准生产临床细胞剂量。在Specific Aim #1中提出的研究将评估采用三种逐渐增加的剂量（108/m2-1010/m2）供体来源的CD19RCD28+HyTK+ ctl克隆与低克隆/多克隆t细胞系进行过继治疗的可行性和安全性，在降低强度的同种异体UCBT治疗高风险CD19* B-ALL后。我们假设淋巴消耗准备方案将促进转移的t细胞的稳态增殖，以及限制抗转基因排斥反应。特异性目标#2中的相关研究重点是利用载体特异性Q-PCR和连续获得的PBMC标本的TCR光谱分型分析，描述在三种规定的t细胞剂量水平下转移克隆与系的持久性的大小和持续时间。我们还将评估重组人IL-2在促进体内转移的t细胞扩增方面的效用。在Specific Aim 3中提出的相关研究将评估移植克隆与系的骨髓和淋巴结运输，以及移植t细胞在B-ALL MRD这些解剖部位的功能状态。总的来说，这些研究的结果将促进CD19特异性t细胞靶向ucbt后MRD的发展，以提高b系ALL患者的无病生存率，并证实将这种方法扩展到HCT治疗的更广泛的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.