RNA DELIVERY FOR DENDRITIC CELL HIV ANTIGEN PREVENTION

描述(由申请人提供)：迫切需要一种安全有效的艾滋病毒疫苗来抗击全球艾滋病的祸害。虽然无论是保护性疫苗还是治疗性疫苗，免疫保护的相关因素都尚未明确，但人们普遍认为，CD4*和CD8细胞以及体液免疫都是重要的。如何才能产生足够广泛、有效和持续的反应还有待确定，这是我们对如何产生有效疫苗以实现保护性免疫的理解上的一个严重差距。树突状细胞(DC)是天然免疫和获得性免疫之间的交界点，是产生免疫反应最有效和最重要的组成部分。因此，我们将重点放在操纵DC的新方法上，以开发其在抗HIV免疫反应中的潜在作用。最近开发的一种特别有希望的DC启动方法是使用抗原编码的mRNA的转染。为此，我们开发了一种新的、高效的树突状细胞负载mRNA的方法，并利用这种方法来最大化DC免疫应答的产生能力。在我们的初步研究中，我们已经证明编码抗原负载的树突状细胞的mRNA能够引发两种CD4 CD8反应。此外，抗原编码的mRNA可以直接注射到小鼠体内，并产生初级和次级T和B细胞免疫反应。此外，我们的实验数据表明，除了提供一种抗原递送方式外，RNA还具有激活DC的独特内在能力。我们的假设是，基于RNA的树突状细胞抗原递送提供了一种独特的灵活和有效的免疫方法，RNA递送的机制可以被操纵来调节产生的反应类型(包括辅助免疫、细胞毒性免疫和体液免疫)，并且这种方法可以被用于开发HIV疫苗。这项建议的目的是更好地了解树突状细胞处理RNA编码抗原的机制，确定RNA编码抗原可能针对特定抗原提呈途径的因素，并为HIV的有效性建立概念验证证据。我们预计，这项工作将加深我们对DC免疫功能的了解，使我们能够差异化地操纵免疫反应中的特定元件，最终使我们能够利用mRNA编码的抗原负载的树突状细胞产生的免疫反应达到潜在的保护和治疗目的，除了为合理开发HIV疫苗的新方法提供基础外，我们希望这些研究也可能为疫苗开发提供一条新的途径。

DESCRIPTION (provided by applicant):A safe and effective vaccine for HIV is critically needed to combat the worldwide scourge of AIDS. While the correlates of immune protection have yet to be clearly defined, either for protective or therapeutic vaccines, it is widely believed that both CD4* and CD8 cell as well as humoral immunity are all important. How sufficiently broad, potent and sustained responses can be elicited has yet to be determined, and this represents a critical gap in our understanding of how to generate an effective vaccine such that protective immunity can be achieved. Dendritic cells (DC) represent the interface between innate and adaptive immunity and are among the most potent and important components in generating immune responses. Therefore, we have focused on novel approaches to manipulating DC in order to exploit their potential role in anti-HIV immune responses. One recently developed and particularly promising approach to priming DC is using transfection of antigen encoded mRNA. Towards this end, we developed a novel, high-efficiency method of loading DC with mRNA, and utilized this approach to maximize DC immune response generation capacity. In our preliminary studies, we have shown that mRNA encoding antigen-loaded DC are able to elicit both CD4 CD8 responses. In addition, antigen-encoded mRNA can be directly injected into mice and generate both primary and secondary T and B cell immune responses. Furthermore, our pilot data suggest that in addition to providing a mode of antigen delivery, RNA has a unique intrinsic ability to activate DC. Our hypothesis is that RNA-based dendritic cell antigen delivery offers a uniquely flexible and potent approach to immunization, that the mechanism of RNA delivery can be manipulated to regulate the types of response generated (including helper, cytotoxic and humoral immunity), and that this approach can be exploited for the development of HIV vaccines. The aim of this proposal is to better understand the mechanisms by which RNA encoded antigen is processed by DC, define the factors by which specific antigen presentation pathways may be targeted by RNA-encoded antigen, and establish proof-of-concept evidence for efficacy in HIV. We anticipate that this work will enhance our understanding of DC immune function, enable us to differentially manipulate specific elements in the immune response, and, ultimately, allow us to exploit mRNA encoded antigen loaded dendritic cell-generated immune responses for potentially protective and therapeutic purposes, in addition to providing a foundation for the rational development of a novel approach to HIV vaccine development, it is our hope that these studies may also offer a new avenue for vaccine development in general.