B-cell Biology of Mucosal Immune Protection from SIV Challenge

描述（由申请人提供）：开发一种安全有效的HIV-1疫苗对于遏制目前影响全球3000多万人的主要性传播疾病的传播至关重要。虽然最近的痘病毒蛋白免疫原效力试验赋予适度的保护，从收购，保护的相关性是未知的。在恒河猴的SIV感染模型中，高达70%的动物，用GM-CSF增强的DNA引发、MVA加强接种，然后进行异源（E660）、多次低剂量直肠攻击，被保护免于获得，并且保护的明确相关性是E660 Env结合抗体亲合力。Emory Consortium for B-Cell Biology of Mucobacterium Immune Protection from SIV Challenge，使用高度合作的方法，将通过先进的免疫学和系统生物学方法来定义增强抗体亲和力和保护的潜在机制。该联盟将包括四个研究项目和四个科学支持核心，以及一个实现这一目标的行政核心。项目1将确定GM-CSF介导增强对低剂量SIV阴道攻击的保护的机制，并将确定添加优化的蛋白质加强是否进一步增强保护。项目2将研究TLR-4和TLR-7配体的潜在和潜在机制，这些配体以新型合成纳米颗粒制剂形式递送，最近显示出显著改善对流感HA的抗体应答，以提高保护性粘膜B细胞和T细胞对SIV VLP的应答质量。项目3将确定GM-CSF和纳米颗粒递送的TLR配体佐剂对滤泡T细胞的作用及其在塑造体液免疫应答质量中的功能，而项目4将类似地研究这些佐剂方法激活具有B细胞辅助功能的产生IL-21的N{BH}嗜中性粒细胞亚群的潜力。这些项目将得到NHP核心的支持，该核心将为研究提供和维持具有遗传特征的雌性猕猴。额外的核心将允许在单细胞和粘膜分泌物水平上表征抗病毒抗体应答，B细胞生物标志物核心将开发用于定义该恒河猴模型中B细胞应答的独特试剂。行政核心将通过数据库和储存库管理确保项目与核心之间的有效沟通和协作，并将负责保持时间表、财务责任和传播研究成果。 公共卫生相关性：Emory Consortium for B-Cell Biology of Mucobacterium Immune Protection from SIV Challenge将定义和表征增强保护免受SIV感染的机制基础，并将探索进一步提高保护水平的新方法。这些研究的结果将直接适用于人类受试者的HIV疫苗开发。 项目1：GM-CSF介导的疫苗效力增强的免疫相关性（项目负责人拉马阿马拉） 申请人提供的说明：由HIV-1引起的获得性免疫缺陷综合征是非洲的主要死因，也是全世界的第四大死因。最近的RV 144 3期试验（泰国试验）测试了由痘病毒载体（ALVAC）初免和蛋白加强组成的艾滋病疫苗的效力，证明了适度的效力，其中25%的接种个体被保护免受HIV-1感染。这些结果非常令人鼓舞;然而，这种保护的免疫相关性尚未确定，但表明非中和抗体在保护中的作用。此外，泰国试验中的保护似乎是短暂的（前六个月），需要开发维持疫苗引起的应答的免疫记忆的方法。 我们正在进行的恒河猴研究表明，DNA初免和痘病毒（改良安卡拉牛痘）加强疫苗（DNA/MVA）对异源重复粘膜SIV攻击具有类似的保护作用。此外，粒细胞和巨噬细胞集落刺激因子（GM-CSF）DNA与我们的疫苗DNA的共递送显著增强了DNA/MVA疫苗介导的保护作用，从25%提高到70%。GM-CSF不辅助抗病毒CD 8 T细胞应答，但增强了对Env特异性的结合Ab的亲合力，并促进直肠分泌物中抗病毒伊加的产生。重要的是，结合抗体对攻击病毒Env的亲合力与增强的对SIV感染的保护密切相关。这些和其他研究的结果突出了抗体的其他非中和活性在保护中的重要作用。 该项目的总体目标是确定GM-CSF介导的增强对粘膜SIV攻击的保护的机制，并测试蛋白加强对增强这种保护对恒河猴中获得异源重复阴道内SIV攻击的作用。在我们的具体目标1中，我们将研究GM-CSF介导的增强保护的免疫相关性。在这里，我们将测试的假设，即GM-CSF增强的广度，亲和力，细胞溶解活性和粘膜归巢的抗Env结合抗体在血清和粘膜分泌物中通过调节抗原呈递细胞和辅助性T细胞反应的功能。 在我们的具体目标2中，我们将测试向GM-CSF佐剂化的DNA/MVA疫苗中添加用明矾或包封在纳米颗粒中的toll样受体配体的组合进行强化的蛋白质加强是否会进一步增强针对获得异源重复阴道内SIV攻击的保护性免疫的寿命。

DESCRIPTION (provided by applicant): The development of a safe and effective vaccine against HIV-1 is critical for curtailing the spread of a primarily sexually transmitted disease that is now affecting more than 30 million persons worldwide. While a recent poxvirus-protein immunogen efficacy trial conferred modest protection from acquisition, the correlates of protection are unknown. In the SIV infection model in Rhesus macaques, up to 70% of animals, vaccinated with GM-CSF enhanced DNA priming, MVA boosted, then subjected to a heterologous (E660), multiple low dose rectal challenge, were protected from acquisition and a clear correlate of protection was E660 Env binding antibody avidity. The Emory Consortium for B-Cell Biology of Mucosal Immune Protection from SIV Challenge, using highly collaborative approaches, will define through advanced immunological and systems biology approaches the underlying mechanisms for enhanced antibody avidity and protection. The Consortium will incorporate four research projects and four science support cores, in addition to an Administrative core to achieve this goal. Project 1 will identify the mechanisms by which GM-CSF mediates enhanced protection from low dose SIV vaginal challenge, and will determine whether addition of an optimized protein boost further enhances protection. Project 2 will investigate the potential and underlying mechanism for TLR-4 and TLR-7 ligands, delivered in a novel synthetic nanoparticle formulation and recently shown to dramatically improve antibody responses to influenza HA, to enhance the quality of protective mucosal B-cell and T-cell responses to SIV VLPs. Project 3 will determine the effects of GM-CSF and nanoparticle delivered TLR ligand adjuvants on follicular T-cells and their function in molding the quality of the humoral immune response, while Project 4 will similarly investigate the potential for these adjuvanting approaches to activate a subset of IL-21 producing N{BH} neutrophils equipped with B cell helper function. The projects will be supported by an NHP Core, which will provide and maintain genetically characterized female macaques for the studies. Additional Cores will allow characterization of the antiviral antibody response at the level of single cells and mucosal secretions, and a B-cell biomarker core will develop unique reagents for defining the B-cell response in this rhesus model. The Administrative Core will ensure effective communication and collaboration between projects and Cores through database and repository management and will be responsible for maintaining timelines, fiscal responsibility, and dissemination of research results. PUBLIC HEALTH RELEVANCE: The Emory Consortium for B-Cell Biology of Mucosal Immune Protection from SIV Challenge will define and characterize the mechanistic basis for enhanced protection from acquisition of SIV infection, and will explore novel approaches to increase further the level of protection. Results from these studies will be directly applicable to HIV vaccine development in human subjects. Project 1: Immune Correlates for GM-CSF Mediated Enhancement of Vaccine Efficacy (Project Leader Rama Amara) Description as provided by applicant: The acquired immunodeficiency syndrome caused by HIV-1 is the leading cause of death in Africa and the fourth leading cause of death worldwide. The recent RV144 phase-3 trial (Thai trial) testing the efficacy of an AIDS vaccine consisting of a poxvirus vector (ALVAC) prime and protein boost demonstrated a modest efficacy where 25% of the vaccinated individuals were protected from HIV-1 infection. These results are highly encouraging; however the immune correlates for this protection are yet to be identified but suggest a role for non-neutralizing Ab in protection. Furthermore, the protection in the Thai trial appeared to be short lived (for the first six months) and there is a need for developing approaches that sustain immunological memory of vaccine elicited responses. Our ongoing studies in rhesus macaques demonstrated a similar protection from heterologous repetitive mucosal SIV challenges by a DNA prime and poxvirus (modified vaccinia Ankara) boost vaccine (DNA/MVA). In addition, co-delivery of granulocyte and macrophage colony stimulating factor (GM-CSF) DNA with our vaccine DNA significantly enhanced the protection mediated by the DNA/MVA vaccine from 25% to 70%. GM-CSF did not adjuvant the anti-viral CD8 T cell responses but enhanced the avidity of binding Ab specific to the Env and promoted generation of anti-viral IgA in rectal secretions. Importantly, the avidity of binding Ab against the challenge virus Env strongly correlated with enhanced protection against acquisition of SIV infection. These and results from other studies highlight an important role for other non-neutralizing activities of antibody in protection. The overall goals of this project are to identify the mechanisms of GM-CSF-mediated enhancement of protection against a mucosal SIV challenge and to test the effect of a protein boost for enhancing this protection against acquisition of heterologous repetitive intravaginal SIV challenges in rhesus macaques. In our specific aim 1, we will investigate the immune correlates for GM-CSF mediated enhanced protection. Here we will test the hypothesis that GM-CSF enhances the breadth, avidity, cytolytic activity and mucosal homing of anti-Env binding Ab in serum and mucosal secretions by modulating function of antigen presenting cells and T helper responses. In our specific aim 2, we will test whether addition of a protein boost, adjuvated with either alum or a combination of toll-like receptor ligands encapsulated in nanoparticles, to the GM-CSF-adjuvanted DNA/MVA vaccine will further enhance the longevity of protective immunity against acquisition of heterologous repetitive intravaginal SIV challenge.