Engineering HIV-resistant CAR T cells for a functional HIV cure

项目摘要/摘要 人类免疫缺陷病毒(HIV)通过快速、快速地破坏宿主细胞免疫反应 病毒逃逸以及高抗原负荷导致慢性免疫激活、T细胞耗尽和免疫 功能障碍。能够完全抑制病毒复制的有效抗逆转录病毒疗法(ART)的出现 大大降低了艾滋病毒感染的发病率和死亡率。然而，抗逆转录病毒治疗必须无限期地被视为艾滋病毒。 在长期稳定的水库中持续存在，因此构成了重大的公共卫生负担，只有 通过预防性疫苗和更有效的治疗方法缓解了这种情况。 鉴于艾滋病毒有效地躲避了细胞免疫反应，并且潜伏的艾滋病毒蓄水池优先 携带相关细胞毒性T淋巴细胞(CTL)逃逸突变的病毒种子，基因工程 模式可能为固有免疫提供了一种有效的替代方案。嵌合抗原受体(CAR)T细胞 在临床上显示出令人印象深刻的消除血细胞癌的效果，并将CAR T细胞重新设计为靶点 使用CD4胞外区的HIV(CD4-CAR T)代表了一种有效的抗逃逸细胞疗法 比传统的细胞毒性T淋巴细胞具有更强的细胞毒功能。 我们最近已经描述了显著增强的双共刺激结构域CAR T细胞的创建 产品(双CARS)，在体内的表现明显优于第三代CAR T细胞。重要的是，这些 研究发现，体内CD4-CAR T细胞效率至少存在两个额外的障碍，这可能会影响翻译 去诊所。首先，CD4-CAR T细胞快速上调多种抑制受体，表达转录因子 与精疲力竭有关，并在体外表现出衰弱的功能。其次，我们的研究明确地表明， 抑制血浆病毒载量需要保护CAR T细胞产物免受艾滋病毒感染。这项建议 寻求通过1)定义如下机制(S)来解决CD4域外CAR T细胞治疗中的这些缺陷 慢性HIV暴露会削弱T细胞功能，2)开发新的组合策略以充分保护 来自HIV感染的CD4-CAR T细胞，最终目标是创造一种T细胞免疫疗法，展示 提高了临床疗效。

Project Summary/Abstract The human immunodeficiency virus (HIV) promptly subverts the host cellular immune response through rapid viral escape, as well as high antigen loads leading to chronic immune activation, T cell exhaustion, and immune dysfunction. The advent of potent antiretroviral therapy (ART) capable of fully suppressing viral replication has drastically reduced the morbidity and mortality of HIV infection. However, ART must be taken indefinitely as HIV persists in long-lived stable reservoirs and thus presents a significant public health burden that can only be alleviated with a preventative vaccine and more potent cure approaches. Given that HIV effectively evades the cellular immune response, and the latent HIV reservoir is preferentially seeded with virus harboring relevant cytotoxic T lymphocyte (CTL)-escape mutations, genetic engineering modalities may offer a potent alternative to intrinsic immunity. Chimeric antigen receptor (CAR) T cells have shown impressive efficacy in eliminating blood cell cancers in the clinic, and CAR T cells re-engineered to target HIV using the CD4 ectodomain (CD4-CAR T) represent a potent escape-resistant cellular therapy demonstrated to have enhanced cytotoxic function over traditional cytotoxic T lymphocytes. We have recently described the creation of a significantly enhanced dual costimulatory domain CAR T cell product (Dual CARs), which significantly outperformed 3rd generation CAR T cells in vivo. Importantly, these studies identified at least two additional hurdles to CD4-CAR T cell efficacy in vivo, which likely informs translation to the clinic. First, CD4-CAR T cells rapidly upregulate multiple inhibitory receptors, express transcription factors associated with exhaustion, and display attenuated function ex vivo. Secondly, our studies definitively show that suppression of plasma viral load requires protection of the CAR T cell product from HIV infection. This proposal seeks to address these deficits in CD4-ectodomain CAR T cell therapy by 1) defining the mechanism(s) by which chronic HIV exposure attenuates T cell function, and 2) developing novel combinatorial strategies to fully protect CD4-CAR T cells from HIV infection, with the ultimate goal of creating a T cell immunotherapy exhibiting enhanced efficacy in the clinic.