Gene-Engineered Stem Cell Memory T-Cells With Anti-HIV Chimeric Antigen Receptors

具有抗 HIV 嵌合抗原受体的基因工程干细胞记忆 T 细胞

基本信息

批准号：
10091936
负责人：
Masakazu Kamata
金额：
$ 32.74万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-18 至 2021-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10091936
关键词：
Gene Engineered Stem Cell Memory

项目摘要

PROJECT SUMMARY CD8+ cytotoxic T-lymphocytes (CTLs) transiently control HIV in infected persons, but eventually fail due to viral mutation and other factors, resulting in persistent or chronic infection. However, reports of CTLs suppressing HIV infection in a few patients indicate that overcoming these barriers would allow for successful CTL-mediated control of HIV infection. Adoptive immunotherapy strategies aim to confer directed and enhanced CTL responses via supplementation of ex vivo-expanded autologous CD8+ T cells expressing a desired antigen-specific T cell receptor (TCR). However, these cells are mostly dysfunctional due to decreased proliferative response and limited CTL activity. Moreover, the requirement for a particular human-leukocyte antigen to properly present antigen to the T cell limits exogenous TCR-based approaches. Thus, such approaches have had minimal effects on reducing HIV-viral load. Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity onto immune effector T cells. In recent years, CAR immunotherapies have been extensively promoted in anti-cancer clinical trials. Of these, adoptively transferred autologous T cells modified with anti-CD19 CAR showed a dramatic impact on B cell lymphomas in acute and chronic lymphocytic leukemia patients. We hypothesize that CAR immunotherapy against HIV-infected cells can eradicate persistently infected cells and HIV latent reservoirs in patients following reactivation. Regarding an anti-HIV CAR, CD4ζ CAR consisting of the extracellular domain of the human CD4 molecule linked to the CD3ζ-chain has been well-studied in vitro and in human clinical trials. This CAR has been shown to mediate highly potent anti-HIV activity in vitro, but had limited effects due to poor survival and functionality of the transduced cells. We considered potential reasons for this failure due to 1) susceptibility of CD4+ T cells and CD8+ T cells expressing CD4ζ CAR to HIV infection, 2) lack of costimulatory signaling domains required for proper effector and memory response, and 3) massive ex vivo expansion of T cells prior to gene modification leading to cellular aging, resulting in poor effector and memory function. Our overall goal is to confer long-term, enhanced HIV-specific effector and memory responses via transplantation of anti-HIV CAR-engineered T cells. We will 1) develop a new class of anti-HIV CAR using HIV- targeting broadly neutralizing antibodies, 2) protect CAR-transduced T cells from HIV-mediated cytotoxicity by co- transduction with anti-HIV genes, 3) introduce costimulatory-signaling domains into anti-HIV CAR to ensure superior effector and memory responses, and 4) use newly identified memory T cells retaining stem cell properties called “stem cell memory T (TSCM) cells” as a carrier vehicle for anti-HIV CAR. TSCM cells self-renew in vitro as well as in vivo and differentiate into effector T cells. Thus, TSCM cells engineered to express HIV-specific CAR provide an inexhaustible source of HIV-specific immune cells. These studies will be further modeled in vivo using the humanized bone marrow, liver and thymus (BLT) mouse system.

项目摘要 CD8+细胞毒性T淋巴细胞（CTLS）在感染者中瞬时控制HIV，但有时由于病毒而失败突变和其他因素，导致持续或慢性感染。但是，CTL抑制艾滋病毒的报告少数患者的感染表明克服这些障碍将允许成功进行CTL介导的对照艾滋病毒感染。收养免疫疗法策略旨在通过指导和增强CTL的反应。表达所需抗原特异性T细胞的Ex exped自体CD8+ T细胞的补充受体（TCR）。但是，由于增殖反应减少和有限，这些细胞主要功能失调 CTL活性。此外，要求特定的人白细胞抗原正确地呈现抗原 T细胞限制了基于TCR的外源方法。那这种方法对减少的影响很小 HIV病毒负荷。嵌合抗原受体（CAR）是人为地设计的受体免疫疗法已在抗癌中广泛提升临床试验。其中，通过抗CD19赛车修饰的适当传递的自体T细胞显示出戏剧性的对急性和慢性淋巴细胞性白血病患者B细胞淋巴瘤的影响。我们假设那辆车对感染HIV感染细胞的免疫疗法可以放射持续感染的细胞和HIV潜在储层重新激活后的患者。关于抗HIV汽车，CD4ζ汽车由由细胞外域组成与CD3ζ链相关的人CD4分子在体外和人类临床试验中得到了很好的研究。这已显示汽车在体外介导高潜力的抗HIV活性，但由于存活率较差而影响有限和转移的单元的功能。我们考虑了由于1） CD4+ T细胞和CD8+ T细胞表达CD4ζ汽车向HIV感染，2）缺乏共刺激信号域适当的效应子和记忆响应所必需的，以及3）基因之前T细胞的大规模离体扩展修饰导致细胞衰老，导致效应子和记忆功能差。我们的总体目标是通过抗HIV汽车工程T细胞的移植。我们将1）使用HIV-开发一类新的抗HIV汽车靶向广泛中和的抗体，2）保护CAR转移的T细胞免受HIV介导的细胞毒性的影响。用抗HIV基因转导，3）将共刺激性域引入抗HIV汽车，以确保优越的效应子和内存响应，以及4）使用新鉴定的记忆T细胞保留干细胞特性称为“干细胞记忆T（TSCM）细胞”是抗HIV汽车的载体车辆。 TSCM细胞在体外也自我更新如体内，并分化为效应T细胞。这是为表达HIV特异性汽车设计的TSCM细胞提供的 HIV特异性免疫细胞的无穷无尽来源。这些研究将在体内进一步建模人源化的骨髓，肝脏和胸腺（BLT）小鼠系统。