Enhancing Immunological Memory Using Aptamertargeted siRNA Delivery to T Cells

使用适体靶向 siRNA 递送至 T 细胞增强免疫记忆

基本信息

批准号：
8760104
负责人：
Eli Gilboa
金额：
$ 31.85万
依托单位：
UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-07-09 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8760104
关键词：
AXIN1 protein Address Affinity Antigens Antiviral Agents Applications Grants Biodistribution Blocking Antibodies Blood Breast Carcinoma CD8B1 gene Cancer Patient Cancer Vaccines Carcinogens Cells Chemosensitization Chronic Clinical Trials Communicable Diseases Development Drug Kinetics Exhibits Generations Genetic Goals Hematopoietic Hematopoietic System Human Human Development Immune Immune response Immune system Immunity Immunologic Memory In Vitro Life Ligands Malignant Neoplasms Mediating Mediator of activation protein Memory Modality Modeling Mus Oligonucleotides Operative Surgical Procedures Pathway interactions Patients Pharmaceutical Preparations Phenotype RNA Interference Raptors Sirolimus Small Interfering RNA Staging T cell differentiation T cell response T memory cell T-Lymphocyte Therapeutic Toxic effect Vaccines Validation aptamer base clinical application cost effective human FRAP1 protein immunogenicity interest mTOR inhibition melanoma memory acquisition nonhuman primate novel prevent public health relevance response tool tumor uptake

项目摘要

DESCRIPTION (provided by applicant): Recent studies in mice, nonhuman primates, and clinical trials in human patients have emphasized the importance of the persistence of the vaccine-induced immune response, immunological memory, in mediating protective immunity against infectious diseases and cancer. Notably, inhibition of mediators of effector differentiatio like mTOR, GSK3b, Blimp-1 or T-bet, using genetic means or whenever available pharmacological agents, not only prevented the accumulation of the short-lived effectors but also redirected the activated T cells to differentiate along the memory pathway, and potentiated vaccine-induced protective immunity in mice. Notwithstanding, pharmacological agents, like rapamycin that was used to inhibit mTOR, often exhibit undesirable immune suppressive effects reflecting the broad distribution of their targets. Here we propose to develop a versatile, broadly applicable, and clinically feasible approach to promote the generation of memory T cell responses that addresses the main limitations of pharmacological agents. We propose to use RNAi to downregulate intracellular mediators of effector differentiation that will be targeted to CD8+ T cells by conjugation to oligonucleotide aptamer ligands. Aptamer and aptamer-siRNA conjugates offer potentially important advantages in terms of synthesis, conjugation, and reduced immunogenicity. The central hypothesis of the proposed studies is that aptamer-targeted siRNA inhibition of intracellular mediators in vaccine-induced CD8+ T cells will enhance their differentiation into long-lasting memory T cells and potentiate antitumor immunity that will be superior to pharmacological agents in terms of reduced toxicity, increased efficacy, and applicability to "nondrugable" intracellular targets. The proposed approach is supported by preliminary studies showing that 4-1BB aptamer-targeted raptor siRNA inhibition of mTORC1 function in activated CD8+ T cells led to the generation of a potent memory response and enhanced vaccine-induced protective immunity in tumor-bearing mice that was superior to that of rapamycin. The specific goal of the studies proposed in this application is to identify a best-i-class aptamer-siRNA conjugate to potentiate vaccine-induced protective immunity as determined in murine tumor models (Aims #1 and #2), that will guide the development of human conjugates capable of promoting the persistence of antigen- activated T cells in vitro (Aim #3). Successful accomplishment of the goals of the proposed studies will set the stage for clinical trials to potentiate vaccine-induced protective immunity in cancer patients using the agents developed in this proposal. Promoting memory differentiation by inhibition of intracellular mediators using siRNAs that are targeted to activated CD8+ T cells by conjugation to oligonucleotide aptamer ligands is arguably novel. The ability to target siRNAs to specific subsets of circulating immune or hematopoietic cells will provide a novel tool to manipulate the immune and hematopoietic systems for both investigational and therapeutic purposes.

描述（由申请人提供）：最近对小鼠、非人类灵长类动物的研究以及对人类患者的临床试验强调了疫苗诱导的免疫反应、免疫记忆的持久性在介导针对传染病和癌症的保护性免疫中的重要性。值得注意的是，使用遗传手段或任何可用的药物制剂抑制效应器分化的介质（如 mTOR、GSK3b、Blimp-1 或 T-bet）不仅可以防止短命效应器的积累，还可以重新引导激活的 T 细胞进行分化沿着记忆途径，并增强疫苗诱导的小鼠保护性免疫力。尽管如此，药物制剂，如用于抑制 mTOR 的雷帕霉素，经常表现出不良的免疫抑制作用，反映出其靶标的广泛分布。在这里，我们建议开发一种多功能的、广泛的适用且临床可行的方法来促进记忆 T 细胞反应的产生，解决药物制剂的主要局限性。我们建议使用 RNAi 下调效应分化的细胞内介质，该介质将通过与寡核苷酸适体配体缀合而靶向 CD8+ T 细胞。适体和适体-siRNA 缀合物在合成、缀合和降低免疫原性方面具有潜在的重要优势。拟议研究的中心假设是，疫苗诱导的 CD8+ T 细胞中细胞内介质的适体靶向 siRNA 抑制将增强其分化为持久记忆 T 细胞，并增强抗肿瘤免疫，在减少毒性、提高功效以及对“非成药”细胞内靶标的适用性。初步研究表明，4-1BB 适体靶向 raptor siRNA 对激活的 CD8+ T 细胞中 mTORC1 功能的抑制导致了荷瘤小鼠产生有效的记忆反应并增强了疫苗诱导的保护性免疫，该方法得到了所提出的方法的支持。优于雷帕霉素。本申请中提出的研究的具体目标是确定最佳 i 类适体-siRNA 缀合物，以增强疫苗诱导的保护性免疫，如在鼠肿瘤模型中确定的（目标#1和#2），这将指导开发能够促进抗原激活的 T 细胞在体外持久存在的人类缀合物（目标#3）。拟议研究目标的成功实现将为临床试验奠定基础，以使用本提案中开发的药物增强癌症患者的疫苗诱导的保护性免疫力。通过使用 siRNA 抑制细胞内介质来促进记忆分化，这些 siRNA 通过与寡核苷酸适体配体缀合而靶向激活的 CD8+ T 细胞，这可以说是新颖的。将 siRNA 靶向循环免疫或造血细胞特定亚群的能力将提供一种新的工具来操纵免疫和造血系统以用于研究和治疗目的。