Cellular and molecular characterization of the digestive tract sub-epithelium

消化道上皮下层的细胞和分子特征

基本信息

批准号：
10381661
负责人：
Ramesh A Shivdasani
金额：
$ 37.83万
依托单位：
DANA-FARBER CANCER INST
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-01 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10381661
关键词：
Address Adult Agonist Anatomy Basic Science Biology Bone Morphogenetic Proteins CD34 gene CD81 gene Cell Line Cell Maturation Cells Clinical Colorectal Cancer Confocal Microscopy Data Development Diffuse Digestive Physiology Disease Epidermal Growth Factor Epithelial Epithelial Cells FOXL1 gene Fibroblasts Gastric mucosa Gastrointestinal tract structure Human In Vitro Infection Inflammatory Bowel Diseases Intestines Knockout Mice Knowledge Lamina Propria Ligands Logic Malabsorption Syndromes Malignant Neoplasms Mesenchymal Mesenchyme Microanatomy Mitotic Molecular Molecular Profiling Mus Myofibroblast Organ Organoids PDGFA gene PDGFRA gene Pathologic Physiological Platelet-Derived Growth Factor alpha Receptor Population Population Heterogeneity Process RNA analysis Recombinants Research Research Project Grants Resolution Signal Transduction Small Intestines Smooth Muscle Actin Staining Method Source Stomach Stromal Cells Supporting Cell Surface Testing Tissues Ulcer Villus WNT Signaling Pathway antagonist base cell injury cell type conditional knockout enteric infection experimental study healing improved inhibitor innovation insight intestinal epithelium novel progenitor response self-renewal single-cell RNA sequencing stem stem cell differentiation stem cells

项目摘要

Project Description Epithelial development, integrity, and turnover in the digestive tract depend on signals from adjacent mesenchymal cells, and defective signaling may underlie aspects of disorders such as Inflammatory Bowel Disease, pathologic response to infection, malabsorption, and cancer. Crucial mesenchymal signals include Wnt factors and bone morphogenetic protein (BMP) agonists and antagonists, and recent research implicates various (CD34+, Foxl1+, PDGFRA+, Gli1+) cell types as possible sources. However, the precise identities, overlap, and requirements of these populations remain unclear. Integrated consideration of high- resolution microscopic anatomy, molecular profiling of diverse marker-defined cells, and single-cell RNA analysis has led us to identify 3 distinct mesenchymal cell types in the mouse small intestine. Cells expressing high platelet-derived growth factor receptor A (PDGFRAhi) lie closest to the epithelium and correspond to recently described Foxl1+ telocytes. These cells express abundant BMPs and congregate particularly at the crypt-villus junction, whereas two PDGFRAlo cell populations are anatomically and molecularly distinct: those located near the crypt stem-cell zone that uniquely co-express PDGFRA, tetraspanin CD81, and the BMP antagonist Gremlin1, and cells in the villus lamina propria that lack surface CD81. These data collectively suggest the novel hypothesis that crucial crypt-villus BMP gradients reflect dense sources of agonists at the villus base and antagonists at the crypt base. Specific Aim 1 will test this hypothesis and further resolve the distinctive features and functions of mesenchymal PDGFRAhi and PDGFRAlo cells in the mouse small intestine. Building on preliminary data that unfractionated PDGFRAlo cells support expansion of ISCs in vitro, we will investigate the possibly opposing functions of pericryptal CD81+ and villus CD81- subpopulations. In response to ISC damage, the mesenchyme triggers crypt progenitors to dedifferentiate, likely through the same soluble factors that maintain uninjured ISC. Aim 2 proposes a systematic, unbiased approach to identify the specific cellular sources of key restitutional signals. We will also test the hypothesis that mesenchymal PDGFRAhi and PDGFRAlo cells depend on the intestinal epithelium to provide varying concentrations of the ligand PDGFA for their survival, proliferation, and distinct physiologic functions. ISC and crypt progenitors have counterparts in the stomach epithelium, which turns over more slowly, depends less on Wnt signaling, and does not extend villi. Mesenchymal PDGFRA+ cells are equally abundant in both organs, with likely important similarities and differences in organization and functions. To better understand gastric stem/progenitor cell control and the underlying signaling logic in both organs, Aim 3 will characterize stomach mesenchymal PDGFRA+ cells in the same depth that we have achieved in the intestine. Together, these studies apply innovative experimental approaches to examine specific hypotheses that address fundamental questions in digestive tract biology.

项目描述消化道上皮的发育、完整性和周转取决于邻近细胞的信号间充质细胞和信号传导缺陷可能是炎症性肠病等疾病的基础疾病、对感染、吸收不良和癌症的病理反应。关键的间质信号包括Wnt因子和骨形态发生蛋白（BMP）激动剂和拮抗剂，以及最近的研究暗示各种（CD34+、Foxl1+、PDGFRA+、Gli1+）细胞类型作为可能的来源。然而，准确的这些人群的身份、重叠和需求仍不清楚。综合考虑高分辨率显微解剖、多种标记定义细胞的分子分析和单细胞 RNA 分析使我们确定了小鼠小肠中 3 种不同的间充质细胞类型。细胞表达高血小板源性生长因子受体 A (PDGFRAhi) 的位置最靠近上皮，并且对应于最近描述的 Foxl1+ 特细胞。这些细胞表达丰富的 BMP 并聚集特别是在隐窝-绒毛交界处，而两个 PDGFRAlo 细胞群在解剖学上和分子上不同：位于隐窝干细胞区附近的那些独特地共表达PDGFRA，四跨膜蛋白 CD81、BMP 拮抗剂 Gremlin1 以及缺乏表面的绒毛固有层中的细胞 CD81。这些数据共同提出了一个新假设，即关键的隐窝绒毛 BMP 梯度反映了绒毛基部激动剂的密集来源和隐窝基部拮抗剂的密集来源。具体目标 1 将对此进行测试假设并进一步解析间充质PDGFRAhi和的独特特征和功能小鼠小肠中的 PDGFRAlo 细胞。基于未分割的 PDGFRALo 的初步数据细胞支持 ISC 的体外扩增，我们将研究隐周周围可能的相反功能 CD81+ 和绒毛 CD81- 亚群。为了应对 ISC 损伤，间充质触发隐窝祖细胞去分化，可能是通过维持 ISC 未受损的相同可溶性因子。目标2 提出了一种系统的、公正的方法来识别关键恢复的特定细胞来源信号。我们还将检验以下假设：间充质 PDGFRAhi 和 PDGFRAlo 细胞依赖于肠上皮为其生存、增殖提供不同浓度的配体PDGFA，和独特的生理功能。 ISC 和隐窝祖细胞在胃上皮中具有对应物，它的周转速度较慢，对 Wnt 信号传导的依赖性较小，并且不会延长绒毛。间充质 PDGFRA+ 细胞在两个器官中的数量相同，可能存在重要的相似点和差异组织和职能。为了更好地了解胃干/祖细胞控制及其潜在机制两个器官中的信号逻辑，目标 3 将表征同一器官中的胃间充质 PDGFRA+ 细胞我们在肠道中达到的深度。这些研究共同应用了创新的实验检验解决消化道生物学基本问题的具体假设的方法。