A new approach to homeostatic maintenance of dendritic epidermal T cells

树突状表皮 T 细胞稳态维持的新方法

• 批准号: 8701918
• 负责人: Yuan Zhuang
• 金额: $ 23.55万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8701918
• 关键词: Acute; Address; Adult; Alleles; Antigens; Automobile Driving; Behavior; Biological; Cell Aging; Cell Lineage; Cell Maintenance; Cell physiology; Cells; Cessation of life; Clonality; Color; Development; Diphtheria Toxin; Dissection; Effector Cell; Epithelium; Frequencies; Gene Activation; Gene Deletion; Genes; Genetic; Genetic Recombination; Guidelines; Health; Histocompatibility Testing; Homeostasis; Immune response; Individual; Infection; Knock-in Mouse; Knowledge; Label; Life; Longevity; Lymphocyte; Maintenance; Memory; Modeling; Mus; Natural regeneration; Neoplastic Cell Transformation; Organism; Outcome Study; Pathway interactions; Play; Population; Proliferating; Receptor Gene; Receptor Signaling; Regulatory Pathway; Reporter; Research; Rest; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Skin; Speed; Stem cells; System; T-Cell Receptor; T-Lymphocyte; Tamoxifen; Therapeutic; Thymus Gland; Tissues; Uterus; V(D)J Recombination; Wound Healing; aged; cell age; cell injury; chemokine; cytokine; fetal; genetic analysis; immune function; knockout gene; neglect; novel strategies; postnatal; progenitor; regenerative; response; self-renewal; tool; tumor

DESCRIPTION (provided by applicant): Homeostatic maintenance of somatic tissues typically requires replacement of damaged or aged cells by young cells generated from progenitors or somatic stem cells. However, not all tissue types are maintained in such a way. Dendritic Epidermal T Cells (DETC) are skin resident γδ T cells, which are exclusively derived from fetal thymus through V(D)J recombination of the T cell antigen receptor (TCR) genes but are maintained as a homogeneous population expressing a canonical γδTCR in the skin epithelium throughout postnatal life. DETC play important roles in epithelium barrier surveillance, tumor surveillance, and wound healing. The entire DETC population is self-sustained throughout life, yet the lifespan and regenerative behavior of individual DETC remain elusive. To facilitate genetic dissection of γδ T cells, our lab now produced the first γδ lineage specific Cre strain. Lineage specific conditional gene activation or deletion can be achieved in a temporally and spatially controlled manner through tamoxifen treatment. This newly established genetic tool provides an unprecedented opportunity for us to track and genetically manipulate DETC during postnatal life. We will use this genetic tool to explore two fundamental issues concerning homeostatic maintenance of DETC in the adult skin: 1) do DETC expand and/or regenerate uniformly during homeostatic maintenance and 2) the necessity of TCR signaling in either long-term maintenance of DETC or routine function such as wound healing. First, we will combine the inducible Cre with a multi-color fluorescent reporter to label DETC and track their clonal behavior in live mice. Second, we will use the inducible Cre system to disrupt the TCR signaling pathway through conditional gene knockout. The homogeneity of DETC TCR supports the idea that antigens play an important role in the initial selection of DETC. Whether TCR signaling is needed for long-term homeostatic maintenance of DETC is not known. The proposed study will lay the groundwork for genetic analysis of regulatory pathways underpinning homeostatic maintenance of DETC in adult life. The study of DETC also serves as an excellent model for understanding the fundamental rules of tissue maintenance in adult life, particularly in the case where tissue maintenance is independent of progenitor or somatic stem cells.

描述（由申请人提供）：体细胞组织的稳态维持通常需要用祖细胞或体细胞干细胞产生的年轻细胞替换受损或老化的细胞。然而，并非所有组织类型都以这种方式维持。树突状表皮 T 细胞 (DETC) 是皮肤驻留 γδ T 细胞，仅通过 T 细胞抗原受体 (TCR) 基因的 V(D)J 重组而源自胎儿胸腺，但在整个出生后的整个生命周期中，其在皮肤上皮细胞中保持为表达典型 γδTCR 的同质群体。 DETC 在上皮屏障监测、肿瘤监测和伤口愈合中发挥重要作用。整个 DETC 群体在一生中都能自我维持，但个体 DETC 的寿命和再生行为仍然难以捉摸。为了促进 γδ T 细胞的基因解剖，我们的实验室现在生产了第一个 γδ 谱系特异性 Cre 菌株。通过他莫昔芬治疗，可以以时间和空间控制的方式实现谱系特异性条件基因激活或缺失。这种新建立的遗传工具为我们在产后生活中追踪和基因操纵 DETC 提供了前所未有的机会。我们将使用这种遗传工具来探讨有关成人皮肤中 DETC 稳态维持的两个基本问题：1）DETC 在稳态维持过程中是否均匀扩展和/或再生；2）TCR 信号传导在长期维持 DETC 或伤口愈合等常规功能中的必要性。首先，我们将诱导型 Cre 与多色荧光报告基因结合起来标记 DETC 并追踪它们在活体小鼠中的克隆行为。其次，我们将使用诱导型 Cre 系统通过条件基因敲除来破坏 TCR 信号通路。 DETC TCR 的同质性支持了抗原在 DETC 初始选择中发挥重要作用的观点。 DETC 的长期稳态维持是否需要 TCR 信号传导尚不清楚。拟议的研究将为成人生活中 DETC 稳态维持的调控途径的遗传分析奠定基础。 DETC 的研究还可以作为理解成人生活中组织维持的基本规则的绝佳模型，特别是在组织维持独立于祖细胞或成体干细胞的情况下。