Focused characterization of non-canonical T cells against SIV

摘要 根据我们目前掌握的信息，一种可以在很大程度上预防艾滋病毒感染的疫苗 部分接种疫苗的人似乎遥不可及。一种更现实的疫苗将是一种钝化的疫苗 急性病毒血症，更重要的是在很长一段时间内保持对病毒的免疫抑制 如果没有抗逆转录病毒药物的帮助。这样的疫苗应该会引起强大的T细胞反应。CMV矢量化 SIV疫苗重新燃起了人们对这样一种疫苗可能实现的希望。成功的关键之一就是 CMV载体疫苗具有显著的启动和维持CD8 T细胞对SIV的反应的能力 以非规范的方式进行限制，特别是针对在 MHC-II和MHC-E分子的背景。然而，目前还不清楚CMV载体疫苗 可以直接转化为艾滋病毒。因此，迫切需要更多的候选疫苗，以产生类似的 这样就可以进行基本的机制实验，以了解其他疫苗平台是如何 可以诱导同样有效的CD8 T细胞反应。为此，我们调查了一部小说 SIV的弱化突变体，在Env细胞质区域只缺少两个氨基酸。这种病毒被称为 ∆GY，在没有中和抗体的情况下诱导强大的T细胞反应，并保护小尾猴 来自多个同源和异源致病SIV。值得注意的是，我们的初步数据表明，∆GY， 像巨细胞病毒一样，在体外可以诱导非规范的CD8 T细胞反应，可以靶向并消除病毒感染的靶点 细胞。在这里，我们建议利用这一现象开始梳理出这些反应。为了做到这一点，我们 将使用毛里求斯食蟹猴(MCM)，与辫子形成鲜明对比的是，这种猕猴表现得非常简单 由于岛上的人口瓶颈，MHC遗传学。在目标1中，我们将用∆GY和 全面描述CD8 T细胞的反应，重点是交替限制的T细胞，包括 确定它们的分子限制。在目标2中，我们将评估这些反应是否可以保护这一点 病原SIVsmE660的猕猴种类。我们还将在体外扩增T细胞系和克隆 给动物接种疫苗，并确定它们在体外消除各种致病挑战病毒的能力。 总之，这种高度集中的实验设计将使我们能够开始解剖非规范的CD8 T细胞， 它们的限制性分子，以及它们抵御各种病毒的能力。我们希望这些数据将导致 旨在破译机制的更大项目，可能与CMV共享，导致这些高度 强大的CD8T细胞交替反应。

Abstract With the information we currently have available, a vaccine that prevents HIV infection outright in a substantial portion of vaccinated individuals seems out of reach. A far more realistic vaccine would be one that blunts acute viremia and, more importantly, maintains immunologic suppression of the virus for long periods of time without the aid of antiretroviral drugs. Such a vaccine should elicit potent T cell responses. The CMV vectored SIV vaccine has reinvigorated hopes that such a vaccine could be possible. One key to the success of the CMV vectored vaccine is its remarkable ability to prime and maintain CD8 T cell responses against SIV that are restricted in non-canonical fashion, specifically targeting SIV derived epitopes that are presented in the context of MHC-II and MHC-E molecules. However, it’s not clear at this time that the CMV vectored vaccine can be directly translated to HIV. Thus, more vaccine candidates are sorely needed that induce similar responses so that basic mechanistic experiments can be conducted to understand how other vaccine platforms can be made to induce similarly effective CD8 T cell responses. To this end, we have investigated a novel attenuated mutant of SIV that lacks just two amino acids in the Env cytoplasmic domain. This virus, termed ∆GY, induces potent T cell responses along with no neutralizing antibodies, and protects pigtail macaques from multiple homologous and heterologous pathogenic SIVs. Remarkably, our preliminary data suggest ∆GY, like CMV, elicits non-canonical CD8 T cell responses that, in vitro, can target and eliminate virus infected target cells. Here, we propose to capitalize on this phenomenon to begin to tease out these responses. To do this, we will use Mauritian cynomolgus macaques (MCM), which, in stark contrast to pigtails, exhibit remarkably simple MHC genetics due to a population bottleneck on the island. In Aim 1, we will vaccinate MCM with ∆GY and comprehensively characterize the CD8 T cell response with focus on alternately restricted T cells, including determining their molecular restriction. In Aim 2, we will assess whether these responses can protect this species of macaque from pathogenic SIVsmE660. We will also expand T cell lines and clones in vitro from the vaccinated animals and determine their capacity to eliminate diverse pathogenic challenge viruses in vitro. Together, this highly focused experimental design will allow us to begin to dissect non-canonical CD8 T cells, their restricting molecules, and their ability to protect from diverse viruses. We hope these data will lead to larger projects designed to decipher the mechanisms, perhaps shared with CMV, that lead to these highly potent alternate CD8 T cell responses.