Defining modes of helper T cell motility within inflamed tissues

定义发炎组织内辅助 T 细胞的运动模式

• 批准号: 8261449
• 负责人: Michael Glen Overstreet
• 金额: $ 2.72万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-14 至 2012-07-20
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8261449
• 关键词: Antibodies; Antigen-Presenting Cells; Architecture; Behavior; CD4 Positive T Lymphocytes; Cell Adhesion Molecules; Cell physiology; Cells; Chronic; Data; Dendritic Cells; Dermis; Disease; Effector Cell; Environment; Event; Extracellular Matrix; Feedback; Foundations; Genetic; Goals; Helper-Inducer T-Lymphocyte; Image; Immune; Immune response; Immunology; In Vitro; Infection; Inflammation; Integrins; Interleukin-13; Interleukin-4; Interleukin-5; Laboratories; Leishmania; Leishmania major; Leukocytes; Life; Location; Lymphocyte; Lymphoid Tissue; Mediating; Mesenchymal; Microscopy; Modeling; Molecular; Movement; Mus; Myosin Type II; Nature; Parasites; Parasitic infection; Pathology; Pathway interactions; Pattern; Peripheral; Phenotype; Photons; Population; Research Training; Residencies; Selectins; Signal Transduction; Site; Small Interfering RNA; Solid; Stream; Surface; System; T-Cell Activation; T-Lymphocyte; T-Lymphocyte Subsets; Testing; Th1 Cells; Th2 Cells; Therapeutic; Tissues; Tumor Necrosis Factor-Beta; Work; antibody inhibitor; base; cell motility; chemokine; cytokine; design; in vivo; interstitial; intravital microscopy; lymph nodes; novel; pathogen; public health relevance; receptor; response; small molecule; therapeutic target; tumor

DESCRIPTION (provided by applicant): Leukocytes have been shown to utilize different modes of motility in vitro, depending on the nature of their surrounding environment. Using a system of intravital 2-photon microscopy to image live T cells within the inflamed dermis of a mouse, we have observed two distinct interstitial crawling phenotypes that were displayed by functionally discrete CD4+ T cell populations. Th1 cells moved rapidly with amoeboid-like motility while Th2 cells crawled with mesenchymal-like motility. These two modes suggest the mechanisms underlying movement of these functionally distinct T cells are distinct. Given the feedback between the extracellular matrix and intracellular signaling through surface receptors (such as integrins), these observations have relevance in a model of Leishmania major, in which our previous data has suggests that there are functional alterations to T cells in the locally infected tissue that may restrict Th1 accumulation. Thus, we will test the hypotheses that 1) Th1 and Th2 effectors T cells utilize different molecular machinery for motility during in vivo interstitial crawling and 2) motility is modified during parasitic L. major infection. Specific Aim 1: Do effector Th1 and Th2 cells utilize distinct mechanisms to crawl in sites of inflammation? Currently, two main modes of interstitial crawling have been described by cell biologists; integrin-dependent (mesenchymal) and integrin-independent, myosin II-dependent (amoeboid) motility. The objective of this aim is to determine the molecular means by which distinct helper T cell populations crawl within the interstitial space of the inflamed dermis. Candidate molecular pathways will be disrupted by antibody-blockade, genetic deletion and siRNA and the effects on motility determined by intravital 2-photon microscopy. Specific Aim 2: Can the migratory and crawling patterns of helper T cells be modulated by local changes induced by a pathogen? In addition to the immunological responses that accompany chronic infection, pathogens such as L. major can induce significant changes in the local milieu. L. major could modulate T cell motility in trans through pathogen-driven changes in architecture and composition of the ECM of the local tissue and in cis through modulating the chemokines and adhesion molecules expressed by the infected host cells. These changes can result local microenvironments that are dramatically different from steady state and even non-parasitized inflamed tissue. The goal of this aim is to evaluate the effects of the L. major-infected tissue microenvironment on Th1 and Th2 cell crawling, as well as the ability of parasitized antigen presenting cells to interact with the different effector T cells subsets. PUBLIC HEALTH RELEVANCE: Using a system of intravital microscopy to image live T cells within the inflamed dermis of a mouse, we have observed two unique crawling phenotypes that were displayed by functionally distinct CD4+ T cell populations. In the current research training plan, we will test whether the different crawling phenotypes observed utilize unique molecular mechanisms in vivo. An understanding of mechanisms employed by functionally distinct effector T cells could present means of preferentially manipulating subsets of tissue-resident effector cells, potentially offering great therapeutic potential for many disease states.

描述（由申请人提供）：根据周围环境的性质，已证明白细胞在体外使用不同的运动模式。使用插入的2光子显微镜系统来对小鼠发炎真皮内的活细胞进行成像，我们观察到了通过功能离散的CD4+ T细胞种群显示的两个不同的间质爬行表型。 Th1细胞迅速使用类似反向运动的运动能力移动，而Th2细胞用间充质样运动爬行。这两种模式表明这些功能不同T细胞的机制是不同的。考虑到通过表面受体（例如整联蛋白）之间的细胞外基质和细胞内信号传导之间的反馈，这些观察结果与利什曼原虫大型模型中的相关性，在这种模型中，我们的先前数据表明，本地感染的组织中T细胞的功能改变可能限制TH1积累。因此，我们将测试1）TH1和Th2效应子T细胞在体内间质爬行过程中利用不同的分子机械来实现运动性，而2）在寄生虫中寄生虫在主要感染过程中进行了修饰。特定的目标1：效应Th1和Th2细胞是否利用不同的机制在炎症部位爬网？目前，细胞生物学家描述了两种主要的间质爬行模式。整联蛋白依赖性（间充质）和整联蛋白独立的肌球蛋白II依赖性（反向动物）运动。该目的的目的是确定分子平均值在发炎真皮的间隙空间内爬行的分子平均值。候选分子途径将受到抗体阻滞，遗传缺失和siRNA的破坏，以及通过弹性2光子显微镜确定的运动性的影响。具体目标2：辅助T细胞的迁移和爬行模式是否可以通过病原体引起的局部变化来调节？除了伴随慢性感染的免疫反应外，诸如L. Major之类的病原体还会引起局部环境的重大变化。 L. Major可以通过病原体驱动的结构变化和局部组织ECM的组成以及顺式调节T细胞运动，并通过调节受感染宿主细胞表达的趋化因子和粘附分子。这些变化可能导致局部微环境与稳态甚至未寄生的发炎组织截然不同。该目的的目的是评估L.主要感染的组织微环境对Th1和Th2细胞爬行的影响，以及寄生的抗原呈递细胞与不同效应T细胞亚群相互作用的能力。 公共卫生相关性：使用浸润显微镜系统来对小鼠发炎真皮内的活细胞进行图像，我们观察到了两种独特的爬行表型，这些表型由功能上不同的CD4+ T细胞群体显示出来。在当前的研究培训计划中，我们将测试在体内使用独特的分子机制观察到不同的爬行表型。对功能上不同效应T细胞采用的机制的理解可以提出优先操纵组织居民效应细胞子集的手段，从而有可能为许多疾病状态提供巨大的治疗潜力。