Resetting immune homeostasis: a non-invasive approach towards HIV eradication

柏林患者接受了来自异基因供体的骨髓细胞的异基因移植， 携带突变，使后代细胞对艾滋病毒感染具有抵抗力，表明根除艾滋病毒是一种有效的方法。 现实的，但很难实现的目标。这一策略强调了更换免疫系统的积极影响， 被感染的宿主的系统通过不能被HIV感染的细胞。我们的团队和其他人使用了一些策略 比骨髓移植侵入性更小，以实现替代CD 4 T细胞的目标， 易受HIV感染的细胞抵抗HIV感染。我们在单组研究中发现 CCR 5修饰的自体CD 4 T细胞的输注导致CD 4 T细胞数量增加， 调节先天性和适应性免疫系统细胞中的促炎反应，和 增强HIV特异性T细胞功能;我们发现在所有接受修饰细胞的受试者中， 总HIV DNA和整合HIV DNA降低log至3 log 10。艾滋病毒储存库的下降与 扩增和长期持续的一种新的T细胞亚群（TSCM），具有干细胞的特征， 细胞持续超过3年，并在所有记忆T细胞亚群中产生后代。在此，我们提出一个 设计用于了解离体诱导的CCR 5的作用的双臂双盲对照临床试验 修饰（通过锌指核酸酶）恢复T细胞稳态和功能以及HIV的衰变 血液和淋巴组织中的持久性。我们将检验细胞免疫重建的假设 对HIV感染具有抵抗力的细胞通过下调免疫调节因子， 炎症驱动免疫衰老，引发免疫功能障碍，导致恢复 适应性免疫，可以控制和消除残留的HIV感染细胞。一组受试者（n=20） 将输注对HIV感染具有抗性的CCR 5修饰细胞，而另一组（n=10）将接受 未修饰的细胞;未修饰的和修饰的细胞将使用相同的制造方法离体扩增。 程序.在目标1中，我们将首先检验以下假设：输注CCR 5缺失细胞的受试者将显示 具有复制能力的HIV储存库的急剧衰减，然后从机械上证实这与 通过比较这种衰减与这种储库中的变化， 在输注未修饰的CD 4 T细胞的受试者中观察到。在目标2中，我们将检验这种衰减在 HIV库将是T细胞中HIV抗性干细胞样亚群的扩增和持续存在的结果。 细胞（TSCM）。在目标3中，我们将检验CD 4 TSCM将通过以下方式恢复免疫稳态的假设： 减少cART治疗的HIV感染受试者中普遍存在的促炎环境，这将导致（目的 4)在恢复免疫功能中，能够消除感染的细胞的残余池， 有复制能力的病毒。最先进的分子、病毒学和免疫学测定将提供 定量和定性评估的规模复制能力艾滋病毒水库，并将 还允许鉴定与先天性和适应性免疫恢复相关的分子机制， 功能这项临床试验将表明，T细胞稳态的恢复和随之而来的T细胞替代， 由免疫活性未感染的T细胞潜伏感染的细胞将导致HIV的显著衰减， 水库

The Berlin patient who received allogeneic transplantation of bone marrow cells from an allogeneic donor who carried a mutation that rendered progeny cells resistant to HIV infection has shown that eradication of HIV is a realistic though difficult goal to reach. This strategy highlighted the positive impact of replacing the immune system of the infected host by cells that cannot be infected by HIV. Our group and others have used strategies less invasive than bone marrow transplantation to achieve the goal of replacing CD4 T cells that are susceptible to HIV infection by cells that are resistant to HIV infection. We have shown in single-arm studies that infusion of CCR5 modified autologous CD4 T cells leads to increased CD4 T cell numbers, down regulation of pro-inflammatory responses in cells of the innate and adaptive immune systems, and enhancement of HIV-specific T cell function; we showed in all subjects who received the modified cells a half log to 3 log10 decrease in total and integrated HIV DNA. This decline in HIV reservoir was associated with the expansion and long term persistence of a novel T cell subset (TSCM) that has features of stemness as these cells persisted for over 3 years and gave rise to progeny in all memory T cell subsets. Herein we propose a two arm double blinded controlled clinical trial designed to understand the role of ex vivo induced CCR5 modification (By Zn-finger nuclease) on the restoration of T cell homeostasis and function and the decay of HIV persistence in blood and lymphoid tissues . We will test the hypothesis that immune reconstitution with cells that are resistant to HIV infection results in a global improvement of immune homeostasis by downregulating the inflammation that drives immune senescence and triggers immune dysfunction and leads to the restoration of adaptive immunity that can control and eliminate residual HIV infected cells. One group of subjects (n=20) will be infused with CCR5 modified cells that are resistant to HIV infection while the other (n=10) will receive unmodified cells; both unmodified and modified cells will be expanded ex vivo using the same manufacturing procedures. In Aim 1 we will first test the hypothesis that subjects infused with CCR5-deleted cells will show dramatic decay of the replication competent HIV reservoir and then mechanistically confirm that this is related to CCR5 modification and not to ex vivo expansion alone by comparing this decay to changes in this reservoir seen in subjects infused with non-modified CD4 T cells. In Aim 2 we will test the hypothesis that this decay in HIV reservoir will be a consequence of expansion and persistence of an HIV resistant stem-cell-like subset of T cells (TSCM). In Aim 3 we will test the hypothesis that CD4 TSCM will restore immune homeostasis by reducing the pro-inflammatory milieu that prevails in cART-treated HIV-infected subjects which will result (Aim 4) in the restoration of an immune function capable of eliminating the residual pool of cells infected with replication competent virus. State of the art molecular, virological and immunological assays will provide quantitative and qualitative assessment of the magnitude of the replication competent HIV reservoir and will also allow the identification of molecular mechanisms associated to restoration of innate and adaptive immune function. This clinical trial will show that restoration of T cell homeostasis and the ensuing replacement of latently infected cells by immune competent uninfected T cells will result in a significant decay in the HIV reservoir.