Exploiting an artificial APC to induce different T cell subsets

利用人工 APC 诱导不同的 T 细胞亚群

• 批准号: 8893693
• 负责人: Yuri Sykulev
• 金额: $ 26.05万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8893693
• 关键词: Adhesions; Adoptive Transfer; Affect; Agonist; Antigen-Presenting Cells; Antigens; Apolipoproteins; Artificial Membranes; Binding; Biological; C-terminal; CD8B1 gene; Cell Adhesion Molecules; Cell Cycle Kinetics; Cell Surface Proteins; Cell Surface Receptors; Cell surface; Cells; Clinical; Complex; Data; Discrimination; Engineering; Exercise; Glass; Goals; His-His-His-His-His-His; Human; Immunity; Immunologic Receptors; Immunotherapy; In Vitro; Infection; Intercellular adhesion molecule 1; Life; Ligands; Lipid Bilayers; Lipids; Major Histocompatibility Complex; Malignant Neoplasms; Mediating; Membrane; Membrane Fluidity; Membrane Proteins; Memory; Modeling; Molecular; Nanostructures; Nickel; Peptide/MHC Complex; Peptides; Physiological; Proteins; Signal Transduction; Solutions; Source; Specificity; Speed; Stem cells; Surface; Surface Antigens; System; T cell response; T cell therapy; T memory cell; T-Cell Activation; T-Lymphocyte; T-Lymphocyte Subsets; Testing; Transgenic Mice; Variant; Viral Cancer; Virus; base; biophysical properties; density; fighting; his6 tag; improved; interest; mathematical model; membrane model; nanodevice; nanodisk; novel; particle; pathogen; programs; public health relevance; receptor; receptor density; receptor-mediated signaling; response; self-renewal; success; therapeutic development; tool

 DESCRIPTION (provided by applicant): The human T cell compartment contains distinct T cell subsets that are very different in their capacity to persist and to respond after ex vivo expansion and adoptive transfer. T cell programming into distinct T cell subsets depends in a large extent on the quality and quantity of the signal delivered to T cells by professional antigen presenting cells (APC). This has stimulated efforts to develop artificial antigen presenting cells (aAPC) that allow for optimal control over the signals provided to T cells. To more closely mimic natural systems, lipid bilayer surfaces have been used as aAPCs, thereby demonstrating a significant effect of membrane fluidity on T cell activation. However, this and other membrane mimics, which have been exploited thus far, cannot be used to organize membrane proteins into microdomains, within which cell surface receptors are clustered. Major histocompatibility complex (MHC) proteins that present antigenic peptides on the surface of antigen- presenting cells (APC) form clusters with each other and with other cell surface proteins. The changes in MHC clustering and co-clustering could serve as a sensitive mechanism to modulate T cell responsiveness. The goal of the application is to develop the model membrane systems that can recapitulate clustering of immune receptors in a controlled manner. We propose to utilize biodegradable nanolipoprotein particles (NLPs) as a universal platform to mimic molecular membrane clustering. NLPs are self-assembled in solution to form discoidal nanostructures containing lipid bilayers stabilized at the perimeter by apolipoprotein molecules. The size of the NLP ranges from 8 to 30 nm that allow capturing up to 50 molecules of soluble ligands and enable us to achieve model cluster size and density close to physiological. We will use the NLPs to assemble pMHC and other membrane ligands into model membrane patches. We will study how changes in the ligands density and composition of these patches affect binding of the model membrane patches to live T cells and the kinetics and magnitude of TCR-mediated signaling. This will provide a basis for the engineering of aAPC bearing the model membrane patches incorporated into lipid bilayers covering the surface of glass beads. Such aAPCs will allow us to calibrate the strength of T cell stimulation. We will utilize these novel aAPCs to vary the strength of stimulation of naïve CD8+ T cells derived from OT-1 TCR transgenic mice in order to induce different subsets of activated T cells with the same specificity. Building of aAPCs is expected to enable us to expand T cells with instructional programs that allow T cells to persist, function, and migrate in a desired fashion after adoptive transfer. The experimental data will also provide the basis for building a mathematical model to characterize how clustering of ligands on an APC surface determines speed, sensitivity and discrimination of the pMHC I ligand by activated and naïve CD8 T cells.

 描述（由申请人提供）：人类 T 细胞区室包含不同的 T 细胞亚群，这些亚群在离体扩增和过继转移后持续存在和做出反应的能力非常不同。 T 细胞编程为不同的 T 细胞亚群在很大程度上取决于专业抗原传递给 T 细胞的信号的质量和数量 呈递细胞（APC）。这刺激了开发人工抗原呈递细胞 (aAPC) 的努力，该细胞可以对提供给 T 细胞的信号进行最佳控制。为了更接近地模拟自然系统，脂质双层表面被用作 aAPC，从而证明膜流动性对 T 细胞激活的显着影响。然而，迄今为止已开发的这种膜模拟物和其他膜模拟物不能用于将膜蛋白组织成细胞表面受体聚集在其中的微域。在抗原呈递细胞 (APC) 表面呈递抗原肽的主要组织相容性复合体 (MHC) 蛋白彼此形成簇，并与其他细胞表面蛋白形成簇。 MHC 聚类和共聚类的变化可以作为调节 T 细胞反应性的敏感机制。该应用的目标是开发模型膜系统，该系统可以以受控方式重现免疫受体的聚集。我们建议利用可生物降解的纳米脂蛋白颗粒（NLP）作为模拟分子膜簇的通用平台。 NLP 在溶液中自组装形成盘状纳米结构，其中含有由载脂蛋白分子稳定在周边的脂质双层。 NLP 的尺寸范围为 8 至 30 nm，允许捕获多达 50 个可溶性配体分子，并使我们能够实现接近生理学的模型簇尺寸和密度。我们将使用 NLP 将 pMHC 和其他膜配体组装成模型膜片。我们将研究这些斑块的配体密度和组成的变化如何影响模型膜斑块与活 T 细胞的结合以及 TCR 介导的信号传导的动力学和强度。这将为aAPC的工程化提供基础，该aAPC带有模型膜片，并结合到覆盖玻璃珠表面的脂质双层中。这样的 aAPC 将使我们能够校准 T 细胞刺激的强度。我们将利用这些新颖的 aAPC 来改变 刺激源自 OT-1 TCR 转基因小鼠的初始 CD8+ T 细胞的强度，以诱导具有相同特异性的不同活化 T 细胞亚群。装甲运兵车的建造 预计将使我们能够通过指导程序来扩增 T 细胞，使 T 细胞在过继转移后以所需的方式持续存在、发挥作用和迁移。实验数据还将为构建数学模型提供基础，以表征 APC 表面上的配体聚集如何决定激活的 CD8 T 细胞和初始 CD8 T 细胞对 pMHC I 配体的速度、灵敏度和辨别力。