Enhancing control of HIV by inhibiting TRAILshort

描述（由申请人提供）：柏林HIV患者被有效治愈，为治愈人类宿主HIV感染的可行性提供了概念证明。可能至少有四个因素促成了柏林病人的艾滋病毒治愈：(i)在骨髓移植前长期和持久地控制了艾滋病毒感染，（ii）细胞毒性化疗杀死了病毒库，（iii）移植了抗感染的CCR5 delta 32细胞，以及（iv）广泛有效的免疫反应，能够根除任何残留的感染。这一病例引发了许多关于如何使艾滋病毒的治愈成为一个更普遍和可实现的结果的科学辩论和猜测。鉴于目前抗逆转录病毒药物的效力，目前的工作重点是开发杀死或清除病毒库的新方法（例如SAHA），开发产生抗感染细胞的新方法（例如CCR5的锌指核酸酶）以及增强对艾滋病毒的免疫控制。TNF相关凋亡诱导因子（TRAIL）是一种分子，其主要功能是作为免疫监视的效应物，它与两种恶性肿瘤的发病机制以及包括HIV在内的病毒感染有关。关于TRAIL在HIV中的作用，大量证据支持在体内HIV感染期间发生的TRAIL失调的作用，并且有充分证据表明，使用HAART治疗HIV感染患者的细胞使用外源性TRAIL可以减少潜伏感染细胞的数量，这是通过定量共培养试验中无法检测到的复制能力病毒水平来测量的。由于TRAIL是由免疫系统的效应细胞（即CD8和/或NK细胞）表达的，我们质疑为什么TRAIL依赖的自然免疫机制不能独立地减少潜伏感染细胞的数量。我们发现来自hiv感染患者的细胞产生一种新的TRAIL剪接变体，我们称之为TRAILshort，它可以拮抗正常的TRAIL信号。因此，我们提出了一种模型，即hiv感染细胞产生TRAILshort可以防止这些细胞被CTL或NK细胞杀死，这使得一部分受感染细胞得以持续存在。目前的研究计划是了解这种TRAIL剪接变体的生物学特性，并开发抑制其的方法，我们将其命名为TRAILshort （TRAILs）。由于我们已经产生了初步数据，证明TRAILs阻断了HIV诱导的CD4 T细胞的杀伤，以及CTL和NK细胞诱导的杀伤，我们现在建议抑制TRAILs作为提高HIV感染CD4 T细胞死亡率的一种手段，从而有助于根除HIV感染细胞的目标，并治愈HIV感染。在这方面，我们有额外的初步数据表明，抑制TRAILs达到了增加HIV感染t细胞杀伤的目标，并增强了CTL和NK细胞对靶细胞的杀伤。

DESCRIPTION (provided by applicant): The Berlin patient who has been effectively cured from HIV provides proof of concept for the feasibility of curing HIV infection from the human host. It is likely that at least four factors have contributed to HIV being cured in the Berlin patient: (i) prolonged and durable control of HIV infection prior to bone marrow transplant, (ii) cytotoxic chemotherapy killing the viral reservoir, (iii) being transplanted with CCR5 delta 32 cells which are resistant to infection, and (iv) a broadly effective immune response which was able to eradicate any residual infection. This case has spurred much scientific debate and speculation as to how to make cure of HIV a more generalizable and an achievable outcome. Given the potency of current antiretroviral agents, current efforts are focusing on developing novel ways of killing or purging the viral reservoir (eg SAHA), developing new approaches to generate cells which resist infection (eg Zinc finger nucleases for CCR5) and enhancing the immune control of HIV. TNF related apoptosis inducing factor (TRAIL) is a molecule whose principal function is as an effector of immune surveillance, and it has been implicated in the pathogenesis of both malignancies, as well as viral infections including HIV. Concerning the role of TRAIL in HIV, considerable evidence supports a role for TRAIL dysregulation occurring during HIV infection in vivo, and there is ample evidence that treatment of cells from HIV-infected patients on HAART with exogenous TRAIL, reduces the number of latently infected cells, as measured by undetectable levels of replication competent virus in quantitative co-culture assays. Since TRAIL is expressed by effector cells (i.e., CD8 and/or NK cells) of the immune system, we questioned why TRAIL-dependent natural immune mechanisms do not independently reduce the number of latently infected cells. We found that cells from HIV-infected patients produce a novel splice variant of TRAIL which we call TRAILshort, which antagonizes normal TRAIL signaling. We therefore propose a model whereby the production of TRAILshort by HIV-infected cells prevents these cells from being killed by either CTL or NK cells, and this allows a subset of infected cells to persist. The current research proposal concerns gaining understanding the biology of and developing ways to inhibit this TRAIL splice variant, which we have named TRAILshort (TRAILs). Since we have generated preliminary data which demonstrates that TRAILs blocks HIV induced killing of CD4 T cells, as well as killing induced by CTL and NK cells, we now propose to inhibit TRAILs as a means of increasing the rate at which HIV infected CD4 Tcells die, and thereby contributing to the goal of eradicating HIV infected cells, and a cure for HIV infection. In this regard, we have additional preliminary data indicating that inhibiting TRAILs achieves the goal of increasing killing of HIV infected T-cells, and enhancing both CTL and NK cell killing of target cells.