The mechanochemical control of T-cell directional migration under flow

流动下T细胞定向迁移的机械化学控制

• 批准号: 9288617
• 负责人: Daniel A Hammer
• 金额: $ 41.69万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9288617
• 关键词: Actins; Address; Adhesions; Adhesives; Automobile Driving; Cell Adhesion Molecules; Cell Line; Cell Therapy; Cells; Communicable Diseases; Communication; Coupling; Cytoskeleton; Dependence; Dependency; Engineering; Event; Exhibits; Generations; Goals; Homing; Human; Immune; Immune system; Inflammation; Inflammatory; Integrin alpha4beta1; Integrins; Intercellular adhesion molecule 1; Lead; Ligands; Ligation; Lymph; Lymphoid; Malignant Neoplasms; Measures; Mechanics; Memory; Methods; Microfabrication; Molecular; Motion; Organ; Pharmacological Treatment; Process; Proteins; Research Personnel; Salmon; Signal Pathway; Signal Transduction; Site; Surface; Swimming; System; T cell response; T cell therapy; T-Lymphocyte; Testing; Time; Vascular Cell Adhesion Molecule-1; Very Late Antigen Receptors; Work; adaptive immune response; biophysical tools; cell motility; chimeric antigen receptor; detector; differential expression; directional cell; fascinate; imaging modality; improved; lymph flow; migration; mucosal addressin cell adhesion molecule-1; novel; novel therapeutic intervention; polydimethylsiloxane; polymerization; receptor; response; therapeutic development; tool; trafficking

The mechanochemical control of T-cell directional migration under flow Daniel A. Hammer (PI) and Janis K. Burkhardt (co-Investigator) Project Summary T-lymphocytes are key players in the adaptive immune response, and motility is critical to their function. T- cells are equipped with multiple different adhesion molecules that interact with ligands that are expressed differentially throughout the immune system. Furthermore, T-cells often must act under an imposed flow field as they traffic through the vasculature and lymphic system. Our goal is to understand how T-cells respond to the different adhesion ligands and shear rates they encounter to effectively migrate to sites of inflammation and immune communication. Understanding this process at the molecular level is important for development of therapeutic strategies to treat inflammatory and infectious diseases, and cancer Recently, we have discovered that directional T-cell migration varies as a function of the type of ligand they encounter and the shear rate to which they are exposed. When placed on a surface bearing vascular cell adhesion molecule-1 (VCAM-1), which engages the 1-integrin receptor VLA-4, T-cells crawl downstream under flow (in the direction of flow). However, when placed on a surface bearing intercellular adhesion molecule-1 (ICAM-1), which engages the 2-receptor LFA-1, T-cells crawl against the direction of flow, like a salmon swims upstream. The magnitude of upstream migration depends on shear rate, with T-cells more committed to upstream migration as the shear rate increases. On surfaces in which adhesion molecules are mixed, any amount of ICAM-1 supports upstream migration. When the flow is removed, T-cells exhibit migrational memory, but only if they have been exposed to both ICAM-1 and VCAM-1. This observation points to a novel mechanism of crosstalk between two distinct integrin receptors. We propose to investigate the mechanisms that drive the upstream migration of T-cells under flow on ICAM-1, and the origins of migrational memory. We hypothesize that upstream migration is caused by 2 integrin forming a catch bond, which holds the cell in place while signals generated by integrin ligation strengthen adhesive interactions and spur the polymerization of actin at the leading edge, driving forward migration. To test this, we will use molecular engineering, flow chambers, micropatterned surfaces, and microfabricated post array detectors (mPADs) to measure forces exerted by the migrating cell. We have preliminary evidence that other motile amoeboid cells such as the immortalized KG1a cell line display the same phenomenon, facilitating our use of molecular engineering tools and imaging methods to identify the relevant molecules. By dissecting the mechanisms that underlie this fascinating phenomenon, we expect to elucidate key features of integrin-dependent T cell trafficking. Our aims in this work are to: 1. Measure the dynamics of T-cell and KG1a directional motion and migrational memory; 2. Identify the signals and clutch molecules responsible for the differential migration under flow in response to 1 and 2 integrin ligands; and 3. Measure the mechanisms of force generation when T-cells spread and crawl directionally on integrin ligands.

T流动下T细胞方向迁移的机械化学控制 Daniel A. Hammer（PI）和Janis K. Burkhardt（共同研究员） 项目摘要 T淋巴细胞是自适应免疫响应中的关键参与者，运动对其功能至关重要。 t- 细胞与多种不同的粘附分子相等，与表达的配体相互作用 在整个免疫系统中的不同。此外，T细胞通常必须在施加的流场下作用 当它们通过脉管系统和淋巴系统流动时。我们的目标是了解T细胞如何回应 它们遇到的不同粘附配体和剪切速率有效地迁移到炎症部位和 免疫通信。在分子一级了解这一过程对于发展 治疗炎症和传染病以及癌症的治疗策略 最近，我们发现方向性T细胞迁移品种是配体类型的函数 相遇和暴露的剪切速率。当放置在带有血管细胞的表面 粘附分子-1（VCAM-1），它与1-积聚蛋白受体VLA-4，T细胞下游爬网 在流动下（流动方向）。但是，放置在具有细胞间粘合剂的表面时 分子-1（ICAM-1），它与2受体LFA-1，T细胞在流动方向上爬行，例如 鲑鱼在上游游泳。上游迁移的大小取决于剪切速率，T细胞更多 随着剪切速率的增加，致力于上游迁移。在粘合分子的表面上 混合，任何数量的ICAM-1都支持上游迁移。当取出流动时，T细胞显示 迁移记忆，但前提是它们已经暴露于ICAM-1和VCAM-1。这个观察点 在两个不同的整联蛋白受体之间的串扰机制。 我们建议调查驱动T流下T细胞上游迁移的机制 ICAM-1和迁移记忆的起源。我们假设上游迁移是由2引起的 整联蛋白形成捕获键，该键合蛋白将细胞固定在适当的位置，而整合素结扎产生的信号 增强粘合剂相互作用并刺激肌动蛋白在前沿的聚合，向前驱动 迁移。为了测试这一点，我们将使用分子工程，流室，微图案表面和 微生物阵列检测器（MPADS）测量迁移细胞施加的力。我们有 初步的证据表明，其他母亲的变形虫细胞（例如永生化的KG1A细胞系显示） 同样的现象，支持我们使用分子工程工具和成像方法来识别 通过剖析这种迷人现象的基础的机制，我们希望 阐明整联蛋白依赖性T细胞运输的关键特征。我们在这项工作中的目标是：1。衡量 T细胞和KG1A的动力学定向运动和迁移记忆； 2。确定信号和离合器 负责响应1和2整联蛋白配体的流量下差异迁移的分子；和3。 当T细胞在整联蛋白配体上散布并爬行时，测量力产生的机理。