Very Late Antigen Integrin Activity on T Cells

T 细胞上的极晚期抗原整合素活性

基本信息

批准号：
8072946
负责人：
YOJI SHIMIZU
金额：
$ 14.14万
依托单位：
UNIVERSITY OF MINNESOTA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-07-06 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8072946
关键词：
Adhesions Adoptive Transfer Amino Acids Animals Antigen-Presenting Cells Antigens CD18 Antigens Cell Adhesion Cell physiology Cell surface Cells Complex Couples Cytoplasmic Tail Development Exons Extracellular Matrix Extracellular Matrix Proteins Family Funding Gene Targeting Gene Transfer Techniques Guanine Nucleotide-Releasing Factor 2 Immune response Immune system In Vitro Integrins Laboratories Mediating Membrane Molecular Conformation Monomeric GTP-Binding Proteins Mus Phorbol Esters Phosphotransferases Play Process Protein Kinase Protein Kinase C Proteins RNA Interference Receptor Signaling Regulation Research Personnel Role Serine Signal Pathway Signal Transduction System T cell response T-Cell Activation T-Cell Receptor T-Lymphocyte Tail Technology Testing Threonine Tissues Transgenic Mice Transgenic Organisms adapter protein adenoviral-mediated adhesion receptor antigen challenge base in vivo member novel pathogen programs protein function protein kinase C kinase receptor response trafficking

项目摘要

DESCRIPTION (provided by applicant): Integrin adhesion receptors play a vital role in cell function and development by mediating the adhesion of cells to other cells and to extracellular matrix proteins. In the immune system, the functional activity of integrins expressed on T lymphocytes is dynamically regulated by the activation state of the T cell in order to promote transient periods of adhesion that facilitate T cell trafficking and antigen recognition in tissue. Stimulation of the antigen-specific CD3/T cell receptor (TCP) complex initiates a signaling cascade that results in a rapid increase in the functional activity of beta l and beta 2 integrins without increases in integrin levels on the cell surface. TCR-mediated integrin activation can be mimicked by phorbol esters such as PMA, implicating effectors downstream of protein kinase C (PKC) in this process. During the prior funding period, we identified a novel adapter protein function for the PKC effector protein kinase D1 (PKD1) in PMA- and TCR-mediated enhancement of beta l integrin function that is associated with increased beta l integrin clustering and activation of the small GTPase Rap1. We propose that the carboxy-terminal end of the beta l integrin cytoplasmic domain regulates integrin function in response to T cell activation by nucleating the formation of a membrane-localized complex consisting of PKD1, Rap1 and the Rap1 guanine nucleotide exchange factor C3G that controls Rap1 activation and subsequent integrin clustering. We propose the use of novel in vitro cell systems and genetically modified mice in order to test this hypothesis and its relevance to T cell function during immune responses in intact animals. In Aim 1, we will define the structural basis for interactions between the beta l integrin cytoplasmic domain and the PKD1/Rap1/C3G complex and determine if the beta l integrin tail is sufficient to control Rap1 activity. In Aim 2, we will use conditional gene targeting and adoptive transfer approaches to define the function of beta l integrin expression in controlling integrin- dependent responses of T cells to antigen challenge in mice. We will specifically determine if beta2 integrin function is dependent on expression of a beta l integrin subunit that couples effectively to PKD1 and Rap1. In Aim 3, we will use RNA interference and adenoviral-mediated gene transfer techniques to elucidate the function of PKD1 in regulating integrin function in vitro and T cell activation responses to antigen in vivo. Together, these studies will define a novel function for both PKD1 and the beta l integrin cytoplasmic domain in regulating integrin function in T cells and will enhance our ability to develop novel therapies that can specifically modulate T cell immune responses.

描述（由申请人提供）：整联蛋白粘附受体通过介导细胞对其他细胞和细胞外基质蛋白的粘附而在细胞功能和发育中起着至关重要的作用。在免疫系统中，在T淋巴细胞上表达的整联蛋白的功能活性受T细胞的激活状态动态调节，以促进促进组织中T细胞运输和抗原识别的瞬时粘附周期。刺激抗原特异性CD3/T细胞受体（TCP）复合物引发了信号级联反应，从而导致βL和β2整合素的功能活性迅速增加而不会增加细胞表面整合素水平。 TCR介导的整联蛋白激活可以被佛波酯（例如PMA）模仿，在此过程中，蛋白激酶C（PKC）的效应子暗示了效应子。在以前的资金期间，我们确定了PKC效应蛋白激酶D1（PKD1）在PMA-和TCR介导的βL整合蛋白功能增强中的新型衔接蛋白功能，与βL整合蛋白聚类的增加和小GTP酶RAP1的激活相关。我们提出，βL整联蛋白细胞质结构域的羧基末端末端通过对T细胞活化的响应来调节整合素的功能，通过对由PKD1，RAP1和RAP1 Guanine核苷酸核苷酸交换因子C3G组成的膜 - 定位复合物的形成，以控制RAP1 RAP1 RAP1激活和随后的整合素。我们建议在完整动物的免疫反应过程中使用新型体外细胞系统和转基因小鼠的使用，以检验该假设及其与T细胞功能的相关性。在AIM 1中，我们将定义βL整联蛋白细胞质结构域与PKD1/RAP1/C3G复合物之间相互作用的结构基础，并确定βL整合素尾部是否足以控制RAP1活性。在AIM 2中，我们将使用条件基因靶向和产物转移方法来定义βL整合素表达在控制小鼠中T细胞对抗原挑战的整合素依赖性反应中的功能。我们将明确确定Beta2整合素函数是否取决于有效耦合到PKD1和RAP1的βL整合素亚基的表达。在AIM 3中，我们将使用RNA干扰和腺病毒介导的基因转移技术来阐明PKD1在体外调节整联蛋白功能和T细胞激活反应中对体内抗原的功能。总之，这些研究将定义PKD1和Beta L整合素细胞质结构域在调节T细胞中的整合素功能中的新功能，并将增强我们开发可以专门调节T细胞免疫反应的新型疗法的能力。