Immunotherapy of B cell lymphoma with NK-T cells

项目总结 表达CD19特异性嵌合抗原受体(CAR.CD19)的T细胞可产生高比例的 难治性B细胞恶性肿瘤患者的完全缓解。然而，这些研究也已经 揭示(I)从大多数儿科患者制备足够数量的CAR-T细胞的困难 患有非霍奇金淋巴瘤(NHL)，以及(Ii)越来越多的NHL患者因以下原因而延迟复发 CAR-T细胞存留不足或肿瘤细胞CD19缺失。项目4的长期目标是 利用NHL的天然和工程特性，开发安全有效的NHL免疫疗法 CD1d限制的Va24不变自然杀伤T(NKT)细胞。NKT是有吸引力的候选人 免疫疗法。它们通过对CD1d+淋巴母细胞的直接细胞毒性或通过 激活其他免疫效应器，如NK细胞；此外，同种异体NKT不产生移植物- 抗宿主病(GvHD)，可制成“现成”产品。我们假设 经设计表达CAR.CD19的同种异体NKT将显示出治疗非霍奇金淋巴瘤的潜力 我们的初步发现支持GvHD的概念：CAR.CD19转导NKT 直接杀伤CD19+B淋巴细胞，可扩大到临床规模，并在体内发挥强大的抗肿瘤活性 异种淋巴瘤模型。我们还证明了NKT的CD62L+子集对于 CD19-T细胞在体内的持久性和抗肿瘤活性，并已设计出保存这一亚群的方法 CD19-NKT扩增过程中细胞数量的变化。以下三个具体目标将验证我们的假设：1) 产生CD62L表达和最大抗淋巴瘤的同种异体CAR.CD19-NKT 潜在的，使用共刺激aAPC(人工抗原提呈细胞，以前在 当前资金期限)。2)检测第三方CAR.CD19-NKTS的安全性和抗肿瘤活性 成人和儿童复发性/难治性B细胞非霍奇金淋巴瘤患者。3)持续性、表型之间的关系 CD19-NKT的功能与临床反应。这项研究将是人类第一次测试 CAR重定向NKT免疫治疗的可行性和治疗潜力。我们的重点是 CAR.CD19在NHL患者的T细胞中表达时，其良好的记录将使我们能够 评估NKT作为非霍奇金淋巴瘤免疫治疗的新平台，可能还包括其他类型的癌症。

PROJECT SUMMARY T cells expressing CD19-specific chimeric antigen receptors (CAR.CD19) can produce high rates of complete remission among patients with refractory B-cell malignancies. However, these studies have also revealed (i) difficulties in preparing sufficient numbers of CAR-T cells from the majority of pediatric patients with non-Hodgkin lymphoma (NHL), and (ii) a growing fraction of NHL patients with delayed relapse due to inadequate persistence of CAR-T cells or loss of CD19 from tumor cells. The long-term goal of Project 4 is to develop a safe and effective immunotherapy for NHL using both the natural and engineered properties of CD1d-restricted Va24-invariant natural killer T (NKT) cells. NKTs are attractive candidates for immunotherapy. They have antilymphoma activity via direct cytotoxicity against CD1d+ lymphoblasts or by activation of other immune effectors, such as NK cells; further, allogeneic NKTs do not produce graft- versus-host disease (GvHD) and can be prepared as “off-the-shelf” products. We hypothesize that allogeneic NKTs engineered to express CAR.CD19 will show curative potential against NHL without the introduction of GvHD, a concept supported by our preliminary findings: NKTs transduced with CAR.CD19 directly kill CD19+ B lymphoblasts, can be expanded to clinical scale, and exert potent antitumor activity in xenogeneic lymphoma models. We have also shown that the CD62L+ subset of NKTs is essential for CAR.CD19-Tcell persistence and antitumor activity in vivo, and have devised means to preserve this subset of cells during CAR.CD19-NKT expansion. The following three specific aims will test our hypothesis: 1) Generate allogeneic CAR.CD19-NKTs with preserved CD62L expression and maximal antilymphoma potential, using the costimulatory aAPCs (artificial antigen-presenting cells, previously generated during the current funding period). 2) Determine the safety and antitumor activity of third-party CAR.CD19-NKTs in adult and pediatric patients with relapsed/refractory B-cell NHL. 3) Correlate the persistence, phenotype and function of CAR.CD19-NKTs with clinical responses. This study will the first in man to test the feasibility and therapeutic potential of immunotherapy with CAR-redirected NKTs. Our emphasis on CAR.CD19, with its favorable track record when expressed by T cells in NHL patients, will allow us to assess NKTs as a novel platform for NHL immunotherapy and perhaps other types of cancer as well.