Determining the role of trogocytosis-mediated signaling on CD4 T cell phenotype and effector functions

确定 trogocytosis 介导的信号传导对 CD4 T 细胞表型和效应功能的作用

• 批准号: 9110454
• 负责人: SCOTT Allen WETZEL
• 金额: $ 7.25万
• 依托单位: UNIVERSITY OF MONTANA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-18 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9110454
• 关键词: Accounting; Antigen-Presenting Cells; Antigens; Autoimmune Diseases; Biological; Biological Process; Biology; CD4 Positive T Lymphocytes; CD80 gene; Cell Therapy; Cell membrane; Cells; Cellular biology; Complex; Data; Excision; Flow Cytometry; Frequencies; Generations; IL4 gene; Immune; Immune response; Immune system; In Vitro; Individual; Interferon Type II; Interleukin-4; Lead; Lymphocyte Activation; MAPK3 gene; MHC Class II Genes; Mediating; Membrane; Microscopy; Monitor; Peptide/MHC Complex; Peptides; Phenotype; Process; Production; Proteins; Regulation; Reporting; Research; Role; Signal Pathway; Signal Transduction; Structure; Surface; Synapses; T-Lymphocyte; Up-Regulation; Viral Tumor Antigens; ZAP-70 Gene; base; cytokine; immune function; immunological synapse; in vivo; insight; molecular rearrangement; pathogen; public health relevance; receptor; research study; transcriptome

 DESCRIPTION (provided by applicant): CD4+ T cell recognition of cognate MHC class II:peptide complexes on antigen presenting cells (APC) triggers large-scale molecular rearrangements at the T-APC interface forming a structure called the immune synapse. At the synapse, T cells capture large membrane fragments and associated proteins from the APC in a process termed trogocytosis. While this phenomenon has the potential to significantly alter the biology of the individual T cell, we currently have only limited understanding of the biological consequences of this process. As a result of trogocytosis, CD4+ T cells display immunological synapse components on their surface including cognate MHC:peptide and costimulatory molecules, such as CD80. We have previously shown that these molecules mediate intracellular signaling within the T cell, presumably by engaging their receptors on the cell. In this proposal we will examine the impact that this signaling has on the individual T cell. Our preliminary data suggests that this trogocytosis-associated signaling maintains effector cytokine (IL-4) production and may mediate the conversion of T cells to a TH2 phenotype in vitro. The central hypothesis of this proposal is that is that trogocytosis-mediated, sustained TCR signaling sustains effector cytokine production and mediates the conversion of trog+ T cells to a TH2 phenotype. This hypothesis will be examined using 2 specific aims: Aim #1) Determine whether the the observed increase in the frequency of trog+ IL-4+ and GATA-3hi cells is the result of signaling from the trogocytosed molecules. Aim #2) Determine whether the observed increase in IL-4 and GATA-3 expression by trog+ cells is reflective of an intrinsic difference in the ability of TH1 and TH2 to perform trogocytosis or the result of selective survival and/or conversion to TH2. Using flow cytometry, qRT-PCR and 3D wide-field deconvolution microscopy, these experiments will involve both in vitro and in vivo approaches to monitor effector cytokine production as a result of cell- autonomous signaling and examination of the phenotype of the cells that have acquired APC membrane fragments via trogocytosis. The results from this proposal will provide important insight into the role of trogycytosis in T cell effector function and effector phenotype and will lad to additional lines of inquiry to elucidate the in vivo functions of trogocytosis.

 描述（由适用提供）：COGNATE MHC II类的CD4+ T细胞识别：抗原呈现细胞上的肽复合物（APC）在T-APC界面上触发大规模分子重排，形成一种称为免疫突触的结构。在突触时，T细胞在称为trogocyocytosis的过程中捕获了来自APC的大膜片段和相关蛋白。尽管这种现象有可能显着改变单个T细胞的生物学，但我们目前对该过程的生物学后果的理解有限。由于trogocyocytosis，CD4+ T细胞在其表面上显示了免疫突触成分，包括同源MHC：肽和共刺激分子，例如CD80。我们先前已经表明，这些分子在T细胞内的细胞内信号传导，大概是通过在细胞上接合其受体。在此提案中，我们将检查该信号对单个T细胞的影响。我们的初步数据表明，这种与曲核细胞增多症相关的信号传导保持效应子细胞因子（IL-4）产生，并可能在体外介导T细胞向Th2表型的转化。该提案的中心假设是，trogocytosis介导的，持续的TCR信号维持效应子细胞因子的产生，并介导Trog+ T细胞转化为Th2表型。该假设将使用2个特定目的进行检查：目标＃1）确定trog+ IL-4+和GATA-3HI细胞的观察到的增加是否是来自trogocypysy分子信号的结果。 AIM＃2）确定Trog+细胞观察到的IL-4和GATA-3表达的增加是否反映了Th1和Th2的能力的内在差异 进行trogocyocytosis或选择性生存和/或转化为Th2的结果。使用流式细胞仪，QRT-PCR和3D宽场反卷积显微镜，这些实验将涉及体外和体内方法，以监测效应子细胞因子的产生 细胞自主信号传导和检查通过trogocytosis获得APC膜片段的细胞表型。该提案的结果将为Trogercytosis在T细胞效应子功能和效应子表型中的作用提供重要的见解，并将与其他询问线联系起来，以阐明trogococytosis的体内功能。