Novel adjuvants of activating RIG-I and inhibiting immune inhibitors for HIV vacc

激活RIG-I并抑制HIV疫苗免疫抑制剂的新型佐剂

• 批准号: 8022924
• 负责人: XUE F HUANG
• 金额: $ 20.05万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-02-08 至 2012-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8022924
• 关键词: Activated B-Lymphocyte; Adjuvant; Agonist; Antibody Formation; Antigen-Presenting Cells; Autoantigens; Biological; Dendritic Cell Vaccine; Dendritic Cells; Enzymes; Epitopes; Generations; HIV; HIV Antigens; HIV Infections; HIV vaccine; Immune; Immune response; Immunization; In Vitro; Infection; Maintenance; Mediating; Memory; Mus; Natural Immunity; Oryctolagus cuniculus; Phase; Play; Role; Signal Transduction; Small Interfering RNA; T cell response; T memory cell; T-Lymphocyte; Testing; Tumor Necrosis Factor Receptor; Ubiquitin; Vaccination; Vaccine Adjuvant; immunogenic; in vitro testing; in vivo; inhibitor/antagonist; mutant; neutralizing antibody; novel; novel strategies; novel vaccines; phase 1 study; prevent; public health relevance; response; tripolyphosphate

DESCRIPTION (provided by applicant): Despite intensive efforts, the immune responses induced by vaccination or natural infection fail to effectively prevent and control HIV infection. Thus, it is important to explore alternative immunization approaches and novel adjuvants to induce protective immune response that is superior to the natural immunity against HIV infection. Dendritic cells (DCs) play a critical role in the activation and maintenance of immune responses, and they are regulated by stimulatory as well as inhibitory signaling. Recently, we found that the ubiquitin-modifying enzyme A20, a negative regulator of RIG-I, TLR and TNFR signaling, play critical roles in limiting the immunostimulatory potency of APCs and the autoreactive response against self-antigens. We demonstrated that silencing of A20 drastically enhanced the stimulatory potency of TLR agonists and DC vaccines to induce both T cell and antibody responses. In this study we aim to explore and develop novel and potent adjuvants for HIV vaccines by inhibiting A20 and stimulating proinflammatory signaling cascades. The central hypothesis of this study is that 5'- triphosphate A20 siRNA (3P-siA20) that activates RIG-I and inhibits A20 can be used as a novel vaccine adjuvant to enhance anti-HIV cellular and humoral responses to higher levels that cannot be achieved by currently described vaccination approaches and may be capable of overcoming HIV's immune evasion and suppression. The specific aims for the exploratory R21 phase study are: 1. To in vitro test whether 5'-PPP-siA20 has a unique dual function of activating RIG-I and inhibiting the key negative regulator A20 of RIG-I, TLR, and TNFR signaling in DCs. 2. To test whether the bifunctional siA20 can potently stimulate DCs to induce stronger systemic and mucosal HIV-specific CTL and Th responses in mice. After completing the milestones of R21 study, we will proceed to the R33 phase study (years 3-5) to accomplish the following aims: 1. To test whether 3P-siA20 can potently stimulate DCs to more efficiently induce systemic and mucosal antibody responses against HIV Env in mice; and 2. To investigate whether in vivo immunization of 3P-siA20 as an adjuvant and HIV Env mutants with enhanced exposure of protective epitopes more efficiently induces memory T cells and neutralizing antibody responses against HIV in mice and rabbits. This study represents the first attempt of developing and testing a dual function molecule of stimulating RIG-I and inhibiting the key negative regulator of proinflammatory signaling as a novel in vivo adjuvant for HIV vaccination. This novel adjuvant could overcome the biological inhibitory barrier in APCs to allow the induction of immune responses against the weakly immunogenic, protective epitopes on HIV. PUBLIC HEALTH RELEVANCE: In this proposed study, we aim to develop a novel in vivo adjuvant capable of activating RIG-I signaling and inhibiting the key inhibitor of proinflammatory signaling for HIV vaccination to induce more potent protective cellular and humoral immune responses. The R21 phase study is intend to prove the concept that 5' triphosphate (3P) A20-siRNA (siA20) will have a unique dual function of activating RIG-I and inhibiting the key negative regulator A20 of TLR, TNFR, and RIG-I signaling in DCs. We will further prove the concept that the initiation of 3P-siA20- mediated signaling and the prolonged and enhanced proinflammatory signaling will potently stimulate DCs to induce stronger HIV-specific T cell responses in mice. After completing the milestones of R21 study, we will proceed to the R33 phase study to determine whether 3P- siA20 will potently stimulate DCs in inducing stronger HIV-specific antibody responses. We will further test whether in vivo immunization of 3P-siA20 as an adjuvant and HIV Env more efficiently induces memory T cells and neutralizing antibody responses against HIV in mice and rabbits. This study represents the first attempt of developing and testing a dual function molecule of stimulating RIG-I and inhibiting the key negative regulator of proinflammatory signaling as a novel in vivo adjuvant for HIV vaccination.

描述（由申请人提供）：尽管进行了大量努力，但疫苗接种或自然感染诱导的免疫应答仍不能有效预防和控制HIV感染。因此，重要的是探索替代的免疫方法和新的佐剂，以诱导保护性免疫应答，这是上级对HIV感染的天然免疫。树突状细胞（Dendritic cells，DC）在免疫应答的激活和维持中起着关键作用，它们受刺激性和抑制性信号的调节。最近，我们发现，泛素修饰酶A20，RIG-I，TLR和TNFR信号的负调节剂，在限制APC的免疫刺激效力和对自身抗原的自身反应性应答中起关键作用。我们证明A20的沉默显著增强TLR激动剂和DC疫苗诱导T细胞和抗体应答的刺激效力。在这项研究中，我们的目标是探索和开发新的和有效的艾滋病毒疫苗佐剂抑制A20和刺激促炎信号级联。本研究的中心假设是，激活RIG-I并抑制A20的5 '-三磷酸A20 siRNA（3 P-siA 20）可用作新型疫苗佐剂，以将抗HIV细胞和体液应答增强至通过目前描述的疫苗接种方法无法实现的更高水平，并且可能能够克服HIV的免疫逃避和抑制。探索性R21期研究的具体目的是：1.体外检测5 ′-PPP-siA 20是否具有激活RIG-I和抑制DCs中RIG-I、TLR和TNFR信号传导的关键负调节因子A20的独特双重功能。2.检测双功能siA 20是否能有效刺激小鼠DC诱导更强的全身和粘膜HIV特异性CTL和Th应答。在完成R21研究的里程碑后，我们将继续进行R33阶段研究（3-5年），以实现以下目标：1.测试3 P-siA 20是否可以有效地刺激DC以更有效地诱导小鼠中针对HIV Env的全身和粘膜抗体应答;以及2.为了研究是否在体内免疫的3 P-siA 20作为佐剂和HIV Env突变体与增强暴露的保护性表位更有效地诱导记忆T细胞和中和抗体反应，对艾滋病毒在小鼠和兔。本研究代表了开发和测试刺激RIG-I和抑制促炎信号传导的关键负调节因子的双功能分子作为用于HIV疫苗接种的新型体内佐剂的首次尝试。这种新的佐剂可以克服APC中的生物抑制屏障，以允许诱导针对HIV上的弱免疫原性保护性表位的免疫应答。 公共卫生关系：在这项拟议的研究中，我们的目标是开发一种新的体内佐剂，能够激活RIG-I信号传导，抑制HIV疫苗接种的促炎信号传导的关键抑制剂，以诱导更有效的保护性细胞和体液免疫应答。R21期研究旨在证明5'三磷酸（3 P）A20-siRNA（siA 20）在DC中具有激活RIG-I和抑制TLR、TNFR和RIG-I信号传导的关键负调节因子A20的独特双重功能的概念。我们将进一步证明3 P-siA 20介导的信号传导的启动以及延长和增强的促炎信号传导将有力地刺激DC在小鼠中诱导更强的HIV特异性T细胞应答的概念。在完成R21研究的里程碑之后，我们将进行R33阶段研究以确定3 P-siA 20是否将有效地刺激DC以诱导更强的HIV特异性抗体应答。我们将进一步测试作为佐剂的3 P-siA 20和HIV Env的体内免疫是否更有效地诱导小鼠和兔中的记忆T细胞和针对HIV的中和抗体反应。本研究代表了开发和测试刺激RIG-I和抑制促炎信号传导的关键负调节因子的双功能分子作为用于HIV疫苗接种的新型体内佐剂的首次尝试。