Targeting HIV-specific T cell differentiation programs to enhance post-treatment control of HIV

项目总结 全世界有近4000万人感染了艾滋病毒，这种感染是无法治愈的。许多策略 旨在治愈艾滋病毒，重点是利用艾滋病毒特异性T细胞来控制在抗逆转录病毒治疗后反弹的病毒 治疗(ART)被终止，因为它们有能力专门识别和杀死艾滋病毒感染细胞。 然而，如果HIV特异性T细胞疗法不能克服T细胞枯竭，那么它们将不会有效 发生在慢性抗原刺激的背景下。在慢性感染和癌症的小鼠模型中，T细胞 丰富的干细胞记忆(TSCM)表型或干细胞样转录程序强健地扩展和 在抵抗疲惫的同时分化为效应细胞。我们发现，这个词的表达 干细胞/记忆促进转录因子TCF-1与HIV-1的高体外增殖能力相关 自然控制HIV感染个体中特异性CD8+T细胞以及TCF-1过度表达导致 体外多肽刺激后更好的HIV特异性T细胞扩增。而为了干细胞而丰富的T细胞 在动物模型中，程序能更好地增殖和控制癌症，目前尚不清楚干细胞样T细胞是否 (相对于，例如，效应器分化的T细胞)是在ART停止后控制HIV的最佳选择。这个 这项建议的首要目标是直接确定T细胞干细胞在促进HIV- 在停止抗逆转录病毒疗法后，特定的T细胞扩大功能效应者群体，以控制艾滋病毒感染。在……里面 目标1，我们将使用多模式高维单细胞表型和转录图谱来建立 干细胞样病毒特异性CD8+T细胞在ART上的比例与其体内扩增是否相关 以及随后在治疗中断后控制人类艾滋病毒或猕猴的SIV。在目标2中，我们将使用 包膜(Env)-靶向具有强大抗HIV活性的HIV特异性CAR-T细胞(Duocar-T细胞)作为模型 问一问精确调整干细胞水平如何影响CAR-T细胞长期抑制HIV的能力 在HIV参与者衍生的异种移植(PDX)小鼠模型中。在目标3中，我们将利用血液和组织 一项非常独特的临床试验对接受抗逆转录病毒治疗的艾滋病毒携带者进行了样本，这些人接受了抗艾滋病毒多卡的注射。 T细胞，并进行ATI。我们假设，在输注之前，更像干细胞的CAR-T细胞(即 我们在输液前识别并跟踪的整个输液前产品或亚群中的CAR-T细胞 体内输注后使用单细胞配对α/βTCR序列作为条形码)将扩展更大、更少- 效应器种群耗尽。这些研究将首次在艾滋病毒感染的背景下测试 令人信服的假设是，干细胞丰富的T细胞具有更强的增殖能力和持久性 能够在体内产生能够更好地控制HIV的效应性T细胞。我们还将全面 评估ART停用后可能与HIV控制相关的其他T细胞分化状态。 这些研究的完成将对HIV特异性T细胞分化状态的作用产生新的认识 在制定有效的以T细胞为基础的艾滋病毒治愈策略方面。

PROJECT SUMMARY Nearly 40 million people world-wide are infected with HIV, an infection for which there is no cure. Many strategies that aim to cure HIV focus on harnessing HIV-specific T cells to control the virus that rebounds after antiretroviral therapy (ART) is discontinued because of their ability to specifically recognize and kill HIV-infected cells. However, HIV-specific T cell therapies will not be effective if they cannot overcome the T cell exhaustion that occurs in the setting of chronic antigen stimulation. In mouse models of chronic infection and cancer, T cells enriched for a stem cell memory (TSCM) phenotype or stem-like transcriptional program robustly expand and differentiate into effector cells while resisting exhaustion. We have found that the expression of the stem/memory-promoting transcription factor, TCF-1, is associated with high in vitro proliferative capacity in HIV- specific CD8+ T cells in individuals who naturally control HIV infection and that TCF-1 overexpression leads to better HIV-specific T cell expansion after in vitro peptide stimulation. While T cells that are enriched for stemness programs proliferate and control cancer better in animal models, it is currently unknown whether stem-like T cells (versus, for example, effector-differentiated T cells) are optimal for controlling HIV after ART is stopped. The overarching goal of this proposal is to directly establish the role of T cell stemness in promoting the ability of HIV- specific T cells to expand a functional effector population to control HIV infection after discontinuation of ART. In Aim 1, we will use multi-modal high-dimensional single cell phenotypic and transcriptional profiling to establish whether the proportion of stem-like virus-specific CD8+ T cells on ART correlates with their in vivo expansion and subsequent control of HIV in humans or SIV in macaques after treatment interruption. In Aim 2, we will use envelope (Env)-targeting HIV-specific CAR-T cells with potent anti-HIV activity (duoCAR-T cells) as a model to ask how precisely tuning the level of stemness influences the ability of CAR-T cells to suppress HIV long-term in the HIV Participant-Derived Xenograft (PDX) mouse model. In Aim 3, we will leverage blood and tissue samples from a highly unique clinical trial of people with HIV on ART who receive an infusion of anti-HIV duoCAR- T cells and undergo an ATI. We hypothesize that CAR-T cells that are more stem-like prior to infusion (i.e., either the CAR-T cells in the total pre-infusion product or sub-populations that we identify pre-infusion and then track in vivo post-infusion using single cell paired α/β TCR sequences as “barcodes”) will expand a larger, less- exhausted effector population. These studies will test for the first time in the context of HIV infection the compelling hypothesis that T cells enriched for stemness have greater proliferative capacity and durability and are able to give rise to effector T cells that are better able to control HIV in vivo. We will also comprehensively evaluate other T cell differentiation states that might associate with HIV control after ART discontinuation. Completion of these studies will result in new knowledge about the role of HIV-specific T cell differentiation states in the development of effective T cell-based strategies for HIV cure.