SIV-specific Mamu-E-restricted CD8+ T cells

描述（由申请人提供）：拟议研究的目标是确定非经典MHC I类分子Mamu-E是否可以将SIV衍生肽呈递给印度恒河猴的免疫系统。然后，我们将确定这些肽的反应是否可以通过疫苗接种引起，以及它们是否可以控制SIV的复制。结核分枝杆菌（Mtb）、巨细胞病毒（CMV）和伤寒沙门氏菌特异性CD 8 + T细胞已显示识别由HLA-E结合的肽。此外，用与抗原加工相关的转运蛋白（TAP）抑制的树突状细胞（DC）接种的小鼠产生Qa-1b-（HLA-E的功能同源物）限制性CD 8 + T细胞，其提供保护免受各种肿瘤的攻击。因此，识别HLA-E或其鼠同源物Qa-1b的CD 8 + T细胞可能在病原体和肿瘤的免疫监视中发挥关键作用。有趣的是，HLA-E，不像其他经典的MHC I类分子，在非人灵长类物种中是很保守的。这种保守程度在这些非人灵长类MHC-E分子的肽结合沟中最为明显，表明MHC-E在人和非人灵长类物种中的结合肽中起重要作用。我们已经在SIV感染的印度恒河猴中进行了初步研究，并且已经表明在IFN 3 ELISPOT测定中识别符合HLA-E结合基序的SIV衍生肽。我们提出了一系列实验来探索SIV特异性Mamu-E限制性CD 8 + T细胞在针对SIV的免疫监视中发挥作用的创新假设。我们将对来自Mamu-E的肽进行测序以确定其肽结合基序，扫描SIVmac 239蛋白质组以寻找预测的Mamu-E结合剂，然后使用IFN 3 ELISPOT用来自SIV感染的印度恒河猴的PBMC筛选这些肽。然后，我们将培养由反应性肽刺激的细胞系，并使用Mamu-E转染子和Mamu-E四聚体确定它们是否确实是Mamu-E限制性的。在本申请的第二部分中，我们假设通过接种疫苗产生Mamu-E特异性CD 8 + T细胞应答将拓宽抗病毒应答的库，并有助于减少病原性异源病毒攻击后的病毒复制。! 公共卫生相关性：寻找艾滋病毒疫苗可能是生物医学研究最重要的目标之一。我们将利用癌症研究的方法来寻找艾滋病毒疫苗的新靶点。!

DESCRIPTION (provided by applicant): The goal of the proposed research is to determine if the non-classical MHC class I molecule, Mamu-E, can present SIV-derived peptides to the immune system of the Indian rhesus macaque. We would then determine if the responses to these peptides can be elicited by vaccination and if they can control SIV replication. Mycobacterium tuberculosis (Mtb)-, Cytomegalovirus (CMV)- and Salmonella typhi-specific CD8+ T cells have been shown to recognize peptides bound by HLA-E. Furthermore, mice vaccinated with Transporter associated with antigen processing (TAP)-inhibited dendritic cells (DCs) develop Qa-1b- (the functional homologue of HLA-E) restricted CD8+ T cells that confer protection from challenge with a variety of tumors. CD8+ T cells that recognize HLA-E or its murine homologue Qa-1b may, therefore, play a critical role in immunological surveillance of both pathogens and tumors. Interestingly, HLA-E, unlike other classical MHC class I molecules, is well conserved across non-human primate species. This degree of conservation is most pronounced in the peptide-binding groove of these non-human primate MHC-E molecules suggesting that MHC-E plays an important role in binding peptides in both humans and non-human primate species. We have conducted preliminary studies in SIV-infected Indian rhesus macaques and have shown that SIV- derived peptides conforming to the HLA-E binding motif are recognized in IFN3 ELISPOT assays. We are proposing a series of experiments to explore the innovative hypothesis that SIV-specific Mamu-E- restricted CD8+ T cells play a role in immune surveillance against SIV. We will elute peptides from Mamu-E to define its peptide-binding motif, scan the SIVmac239 proteome for predicted Mamu-E binders and then screen these peptides using IFN3 ELISPOT with PBMC from SIV- infected Indian rhesus macaques. We will then grow cell lines that are stimulated by the reactive peptides and determine whether they are indeed Mamu-E-restricted using Mamu-E transfectants and Mamu-E tetramers. In the second part of our application we hypothesize that the generation of Mamu-E-specific CD8+ T cell responses by vaccination will broaden the repertoire of antiviral responses and aid in reducing viral replication after challenge with a pathogenic heterologous virus. ! PUBLIC HEALTH RELEVANCE: Finding a vaccine for HIV is probably one of the most important goals of biomedical research. We will use approaches derived from cancer research to try to find new targets for an HIV vaccine. !