Yellow Fever, rDNA (EP+IL-12) and rAd35 as Vectors for AIDS Vaccine Development

描述(申请人提供)：我们计划探索高度成功的减毒黄热病(YF-17D)疫苗，通过电穿孔传递的rDNA以及IL-12和rAd35是否可以作为载体，在主/增强方案中表达SIV蛋白，用于抗艾滋病病毒疫苗。在一系列高度集成的实验中，我们将首先确定疫苗的最佳病毒靶点。然后，我们将在最终的疗效实验中将结果汇集在一起，以测试这些载体，如果成功，可以防止数百万人遭受 世界各地的人们。我们的申请旨在解决HIVRAD计划公告中概述的十个研究领域中的四个。我们的项目有可能在两个方面影响艾滋病毒疫苗的开发。首先，我们将在挑战实验中确定成功疫苗的目标。这将使我们能够设计一种疫苗，编码成功免疫反应的关键靶点。第二，我们将开发三种全新的疫苗载体。如果我们在这一努力中取得成功，我们的结果将对艾滋病毒疫苗的设计产生深远的影响。 与公共卫生相关：完成这些研究应该会产生新的疫苗设计方法。此外，如果我们的三个载体中的任何一个能够有效地在非人类灵长类动物中诱导有效的艾滋病病毒特异性免疫反应，我们就可以将这些载体推进到人类临床试验中。 ******************************************************************************************************************** 项目1：保护性豁免 项目负责人：大卫·沃特金斯 (申请人提供的描述)我们假设，重组黄热病疫苗(RYF)或rDNA(与IL-12一起通过电穿孔传递；EP+IL-12)初始，然后是重组腺病毒血清35型(RAd35)增强，可以在同源或异种艾滋病病毒攻击后控制病毒复制。我们计划在猕猴身上测试这一假设，使用高致病性SIV分离株SIVmac251和SIVsmE660的严格挑战。在之前的一项研究中，我们发现，在8只接种过疫苗的印度猕猴中，有6只在致病性SIVsmE660黏膜攻击后，rDNA启动和rAd5启动(编码除Env外的所有SIVmac239蛋白)减少了急性和慢性期复制。事实上，在挑战后的一年里，六名接种疫苗的人没有检测到病毒复制。在使用致病性SIV挑战的疫苗实验中，这种积极的结果是极其罕见的。我们还发现，疫苗诱导的针对GAG和VIF的T细胞反应与这一良好结果相关。我们推测，在SIV蛋白质组中有其他靶点可以诱导有效的T细胞反应。最近，我们在LAVI的同事已经证明，由EP和编码IL-12的质粒一起接种编码所有SIV蛋白(包括Env)的rDNA质粒，然后再接种rAd5 Boost，可以减少8只猕猴中7只的高致病性SIVmac239挑战病毒的病毒复制。事实上，这些疫苗结果，加上Louis Picker最近使用重组恒河猴巨细胞病毒(RhCMV)载体的发现，是迄今为止最令人鼓舞的非人类灵长类疫苗结果。我们现在的目的是进行一项疫苗研究，以确定哪些SIV蛋白在我们的FIRST特定目标中作为控制病毒复制的重要靶标。为了改进最后两个实验，我们还将在疫苗中加入新发现的神秘开放阅读框架(CORF)。我们的第二个特定目标是确定ryf或rDNA(EP+IL-12)启动后再加上rAd35增强是否可以控制同源或异种艾滋病病毒攻击后的病毒复制。

DESCRIPTION (provided by applicant): We plan to explore whether the highly successful attenuated yellow fever (YF-17D) vaccine, rDNA delivered by electroporation along with IL-12 and rAd35 can be used as vectors to express SIV proteins in a prime/boost regimen for vaccination against the AIDS virus. In a highly integrated series of experiments, we will first define the best viral targets for a vaccine. We will then bring the results together in a final efficacy experiment to test the vectors that, if successful, could prevent suffering by millions of people worldwide. Our application seeks to address four of the ten research areas outlined in the HIVRAD program announcement. Our project has the potential to impact HIV vaccine development on two fronts. First, we will define the targets of a successful vaccine in a challenge experiment. This will allow us to design a vaccine encoding the critical targets of a successful immune response. Second, we will develop three entirely novel vaccine vectors. If we are successful in this endeavor, our results will have a profound effect on HIV vaccine design. PUBLIC HEALTH RELEVANCE: Completion of these studies should yield new methods of vaccine design. Furthermore, if any of our three vectors can effectively induce efficacious AIDS virus-specific immune responses in non-human primates, we could advance these vectors into human clinical trials. ******************************************************************************************************************** Project 1: Protective Immunity Project Leader: David Watkins (Description as provided by applicant) We hypothesize that a recombinant yellow fever vaccine (rYF) or rDNA (delivered by electroporation along with IL-12; EP+IL-12) prime followed by a recombinant adenovirus serotype 35 (rAd35) boost can control viral replication after either a homologous or heterologous AIDS virus challenge. We plan to test this hypothesis in macaques using rigorous challenges with the highly pathogenic SIV isolates, SIVmac251 and SIVsmE660. In a previous study, we found that a rDNA prime followed by a rAd5 boost (encoding all of the SIVmac239 proteins except for Env) reduced acute and chronic phase replication after a pathogenic SIVsmE660 mucosal challenge in six of eight vaccinated Indian rhesus macaques. Indeed, six of the vaccinees have no detectable viral replication at one year post challenge. This positive outcome is exceedingly rare in vaccine experiments using a pathogenic SIV challenge. We also discovered that vaccine-induced T cell responses against Gag and Vif correlated with this good outcome. We postulate that there are additional targets in the SIV proteome that can induce efficacious T cell responses. More recently our colleagues at lAVI have shown that vaccination with rDNA plasmids encoding all of the SIV proteins (including Env) by EP along with a plasmid encoding IL-12, followed by a rAd5 boost reduced viral replication of the highly pathogenic SIVmac239 challenge virus in seven of eight macaques. Indeed these vaccine results, along with the recent findings of Louis Picker using recombinant rhesus cytomegalovirus (rhCMV) vectors are the most encouraging non-human primate vaccine results to date. Our intention now is to perform a vaccine study to determine which of the SIV proteins are important as targets for the control of viral replication in our firs specific aim. In an attempt to improve upon these last two experiments we will also include newly discovered cryptic open reading frames (cORFs) in the vaccine. Our second specific aim is to determine whether a rYF or rDNA (EP+IL-12) prime followed by a rAd35 boost can control viral replication after either a homologous or heterologous AIDS virus challenge.