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

• 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
• 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

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（由申请方提供）：最近在小鼠、非人灵长类动物中进行的研究和在人类患者中进行的临床试验强调了疫苗诱导的免疫应答、免疫记忆的持续性在介导针对感染性疾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理学试剂抑制效应分化的介质如mTOR、GSK 3b、Blimp-1或T-bet，不仅防止了短寿命效应物的积累，而且还使活化的T细胞重新定向以沿着记忆途径分化，并增强了小鼠中疫苗诱导的保护性免疫。尽管如此，药理学试剂，如用于抑制mTOR的雷帕霉素，通常表现出不期望的免疫抑制作用，反映了其靶标的广泛分布。在这里，我们建议开发一个多功能，广泛 因此，本发明提供了一种适用的、临床上可行的方法来促进记忆T细胞应答的产生，其解决了药理学试剂的主要局限性。我们建议使用RNAi下调效应分化的细胞内介质，其将通过与寡核苷酸适体配体缀合而靶向CD 8 + T细胞。适体和适体-siRNA缀合物在合成、缀合和降低的免疫原性方面提供了潜在的重要优势。 提出的研究的中心假设是，在疫苗诱导的CD 8 + T细胞中，适体靶向siRNA抑制细胞内介质将增强其分化为持久记忆T细胞，并增强抗肿瘤免疫力，在降低毒性、提高疗效和适用于“不可用药”细胞内靶点方面上级药理学药物。所提出的方法得到了初步研究的支持，初步研究表明，4-1BB适体靶向的Raptor siRNA抑制活化的CD 8 + T细胞中的mTORC 1功能，导致产生有效的记忆反应，并增强荷瘤小鼠中疫苗诱导的保护性免疫，上级雷帕霉素。本申请中提出的研究的具体目标是鉴定最佳i类适体-siRNA缀合物以增强如在鼠肿瘤模型中确定的疫苗诱导的保护性免疫（目的#1和#2），其将指导能够促进抗原活化的T细胞在体外的持久性的人缀合物的开发（目的#3）。成功实现拟议研究的目标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可以说是新颖的，所述siRNA通过与寡核苷酸适体配体缀合而靶向活化的CD 8 + T细胞。将siRNA靶向循环免疫或造血细胞的特定亚群的能力将为研究和治疗目的提供操纵免疫和造血系统的新工具。