Harnessing adaptive NK cell transfer to deplete viral reservoirs

项目总结 自然杀伤(NK)细胞凭借其能力提供对病毒和肿瘤的即时防御 在没有抗原刺激的情况下对感染或恶性细胞做出反应。这是通过 激活和抑制NK细胞受体(aNKRs和iNKRs)的信号整合。在人类和其他 灵长类物种，包括C型凝集素受体，如CD94/NKG2A和CD94/NKG2C，以及 高度多态的杀伤细胞免疫球蛋白样受体(KIR)，两者都与MHC-I类相互作用 配基。这些受体-配体的相互作用是NK细胞分化健康的能力的基础 并为“NK细胞”的发育提供了一种潜在的特异性机制 记忆“。NK细胞可以对HIV-1感染产生重大影响。KIR和人类白细胞抗原I类基因多态性有 已发现与较低的病毒载量和较慢的疾病进程有关，以及 某些NK细胞亚群可以杀死培养中的HIV感染细胞。因此，以NK细胞为基础的疗法代表了一种 针对HIV感染细胞和缩小病毒库大小的有希望的方法。我们假设 由aNKRs的MHC-I类配体结合的病毒多肽对NK细胞的识别和杀伤至关重要 HIV/SIV感染细胞和过继转移体外激活的NK细胞与潜伏期相结合 在抑制性抗逆转录病毒治疗(ART)中，逆转可耗尽SIV感染猕猴的病毒库。 在目标1中，我们将确定aNKRs的MHC-I类配体结合的病毒多肽对NK的贡献。 HIV和SIV感染细胞的细胞识别。这些研究将利用高通量细胞分析来 快速筛选病毒多肽与aNKRs的MHC-I类相互作用并鉴定破坏的替换 这些互动。将在HIV-1和SIV中引入相应的变化，以评估它们对 NK细胞对病毒感染细胞的反应。在目标2中，我们将评估体外扩增的NK细胞在 在SIV感染、ART抑制的恒河猴中，联合潜伏期逆转耗尽病毒储备库 猕猴。这一目标将利用条形码SIV和一种有效的新潜伏期反转剂进行比较 最敏感的是自体与异体NK细胞移植降低病毒率的能力 在停止使用艺术后重新激活。在目标3中，我们将检验病毒储备库的耗尽 通过适应性NK细胞转移可被具有抗体依赖细胞的环境特异性抗体增强 对SIV感染细胞的细胞毒作用。该目标将使用与目标2类似的方法来确定 哪一种将NK细胞效应器功能与抗体无与伦比的特异性偶联才能最大限度地储存 耗尽。这些史无前例的研究将更好地了解病毒多肽在NK中的作用 HIV/SIV感染细胞的细胞识别与NK细胞发育的重要概念验证 根除慢性感染者体内HIV-1蓄积物的治疗方法。

PROJECT SUMMARY Natural killer (NK) cells provide an immediate defense against viruses and tumors by virtue of their ability to respond to infected or malignant cells without prior antigenic stimulation. This is accomplished through the integration of signals from activating and inhibitory NK cell receptors (aNKRs & iNKRs). In humans and other primate species, these include C-type lectin receptors, such as CD94/NKG2A and CD94/NKG2C, and the highly polymorphic killer-cell immunoglobulin-like receptors (KIRs), both of which interact with MHC class I ligands. These receptor-ligand interactions are fundamental to the ability of NK cells to differentiate healthy cells from unhealthy cells and provide a potential mechanism of specificity for the development of “NK cell memory”. NK cells can have a significant impact on HIV-1 infection. KIR and HLA class I polymorphisms have been identified that are associated with lower viral loads and slower courses of disease progression and certain NK cell subsets can kill HIV-infected cells in culture. Thus, NK cell-based therapies represent a promising approach for targeting HIV-infected cells and reducing the size of viral reservoirs. We hypothesize that viral peptides bound by the MHC class I ligands of aNKRs are critical to NK cell recognition and killing of HIV/SIV-infected cells and that the adoptive transfer of ex vivo activated NK cells in combination with latency reversal can deplete viral reservoirs in SIV-infected macaques on suppressive antiretroviral therapy (ART). In Aim 1, we will determine the contribution of viral peptides bound by MHC class I ligands of aNKRs to NK cell recognition of HIV- and SIV-infected cells. These studies will utilize high-throughput cellular assays to rapidly screen viral peptides for MHC class I interactions with aNKRs and to identify substitutions that disrupt these interactions. The corresponding changes will be introduced into HIV-1 and SIV to assess their impact on NK cell responses to virus-infected cells. In Aim 2, we will assess the capacity of ex vivo expanded NK cells in combination with latency reversal to deplete viral reservoirs in SIV-infected, ART-suppressed rhesus macaques. This aim will take advantage of barcoded SIV and a potent new latency reversal agent to compare with maximal sensitivity the ability of autologous versus allogeneic NK cell transfer to reduce the rate of viral reactivation after discontinuing ART. In Aim 3, we will test the hypothesis that the depletion of viral reservoirs by adaptive NK cell transfer can be enhanced by an Env-specific antibody with antibody-dependent cellular cytotoxicity against SIV-infected cells. This aim will use a similar approach as Aim 2 to determine the extent to which coupling NK cell effector function to the unparalleled specificity of antibodies can maximize reservoir depletion. These unprecedented studies will provide a better understanding of the role of viral peptides in NK cell recognition of HIV- and SIV-infected cells and an important proof-of-concept for the development of NK cell therapies to eradicate HIV-1 reservoirs in chronically infected individuals.