Induction of mucosal SIV immunity in non human primates by secreted Hsp-Gp96

通过分泌的 Hsp-Gp96 诱导非人灵长类动物粘膜 SIV 免疫

• 批准号: 7786796
• 负责人: ECKHARD R PODACK
• 金额: $ 45.9万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-15 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7786796
• 关键词: Immunity; SIV; nonhuman primate

DESCRIPTION (provided by applicant): Cellular immunity and memory is required for clearance of viruses and for protection from viral infection. Cellular immunity by CD8 CTL and NK cells is initiated through activation of the innate immune response, maturation of dendritic cells (DC) and antigen cross presentation to CD8 T cells. Anti viral vaccines stimulating cellular immunity have to imitate this process. Adjuvants for the stimulation of antibody responses are used effectively however our knowledge about adjuvants for the stimulation of CTL immunity is limited. We have demonstrated that the endoplasmic reticulum resident heat shock protein gp96, a chaperone for peptides transported to be presented by MHC-I, is a natural adjuvant for the activation of DC, NK and cognate CD8 T cells. DC and macrophages have receptors for gp96-peptide complexes and become activated upon gp96-binding. Gp96 together with its associated peptides is taken up the APC, the peptide moiety is transported to the ER and used to charge MHC-I molecules. Concomitant activation of DC results in more than million fold enhanced cross priming of cognate CD8 T cells when compared to cross priming by intact protein taken up by DC. To take advantage of this unique adjuvant effect and the ability to transport relevant peptides, we have made a secretable form of gp96, gp96-lg, by replacing the KDEL ER-retention signal with the Fc portion of lgG1. We hypothesize that cell-based gp96-lg vaccines, by prolonged in vivo secretion of gp96-lg-peptide, imitate viral replication and provide immune stimuli comparable to attenuated viruses. In model systems in mice we have shown that gp96-lg transfected, antigen expressing tumor cells secrete gp96-lg in vivo and stimulate the innate DC and NK as well as adaptive, cognate cellular CD8 CTL immune response and generate specific CD8 memory independent of CD4 help and in the absence of lymph nodes. Both systemic and strong mucosal immunity in intraepithelial, lamina propria and Peyer's patch CD8 CTL is generated by gp96-lg vaccines. Because of their unique properties we now plan to evaluate the gp96- vaccines in non-human primate models for SIV for their immunogenicity for mucosal and systemic cellular immunity (R21). In addition we will examine the protective power of SIV-gp96-vaccines against subsequent viral challenge (R33). To maximize the chances of success, the team in Miami (Podack/Pahwa) has entered into a collaboration with experts (Franchini lab) at the NIH bringing together basic immunologists with experts in human and non human primate HIV/SIV pathogenesis.

描述（由申请人提供）：清除病毒和防止病毒感染所必需的细胞免疫和记忆。 CD8 CTL和NK细胞的细胞免疫是通过激活先天免疫反应，树突状细胞（DC）的成熟和抗原交叉表现到CD8 T细胞而开始的。刺激细胞免疫的抗病毒疫苗必须模仿该过程。有效地使用了用于刺激抗体反应的佐剂，但是我们对刺激CTL免疫的辅助因素的了解是有限的。我们已经证明，内质网驻留热休克蛋白GP96是一种由MHC-I提出的肽的伴侣，是激活DC，NK和Cognate CD8 T细胞的天然佐剂。 DC和巨噬细胞具有用于GP96肽复合物的受体，并在GP96结合时被激活。 GP96及其相关的肽被吸收在APC上，将肽部分转运到ER，并用于为MHC-I分子充电。与通过直流吸收的完整蛋白相比，DC的伴随激活导致同源CD8 T细胞的交叉启动超过百万倍。为了利用这种独特的佐剂效应和运输相关肽的能力，我们通过用LGG1的FC部分代替了KDEL ER-驱动信号，从而使GP96，GP96-LG形成了一种分泌的形式。我们假设基于细胞的GP96-LG疫苗通过长时间的体内分泌GP96-LG肽，模仿病毒复制，并提供与减毒病毒相当的免疫刺激。在小鼠中的模型系统中，我们已经表明，GP96-LG转染的抗原表达肿瘤细胞在体内分泌GP96-LG，并刺激先天DC和NK以及自适应，同时同能细胞CD8 CTL CTL免疫反应并产生特定的CD8记忆，对CD4的帮助和无淋巴结不存在CD4的帮助和无关。 GP96-LG疫苗产生上皮内，固有薄片和Peyer贴片CD8 CTL的全身性和强粘膜免疫。由于其独特的特性，我们现在计划评估非人类灵长类动物模型中的GP96-疫苗的SIV，以用于其粘膜和全身细胞免疫的免疫原性（R21）。此外，我们将检查SIV-GP96-VACCINES防止随后的病毒挑战的保护能力（R33）。为了最大程度地利用成功的机会，迈阿密（Podack/Pahwa）的团队已与NIH的专家（Franchini Lab）合作，将基本​​免疫学家与人类和非人类灵长类动物HIV/SIV的专家汇集在一起​​。