Cellular and Molecular Mechanisms of Murine Digit Regeneration

小鼠手指再生的细胞和分子机制

• 批准号: 9889795
• 负责人: Feini Qu
• 金额: $ 6.01万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-02-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889795
• 关键词: Ablation; Adult; Affect; American; Amphibia; Amputation; Amputees; Attenuated; Beds; Bioinformatics; Biological; Bone Regeneration; Cell Lineage; Cell Proliferation; Cells; Complex; Cues; Devices; Differentiation Antigens; Digit structure; Disease; Distal; Epithelial; Epithelium; Event; Excision; Failure; Fluorescent in Situ Hybridization; Ganciclovir; Growth; Growth Factor; Human; In Situ Hybridization; Investigation; Label; Limb structure; Mammals; Mediating; Mesenchymal; Methods; Modeling; Molecular; Molecular Target; Mus; Musculoskeletal; Nail plate; Natural regeneration; Organ; Osteoblasts; Paracrine Communication; Pathway interactions; Patient-Focused Outcomes; Periosteal Cell; Periosteum; Play; Population; Process; Production; Proliferating; Proliferation Marker; Prosthesis; Quality of life; RNA; Regenerative Medicine; Regenerative response; Regulator Genes; Regulatory Pathway; Rehabilitation therapy; Reporter; Research Personnel; Role; Signal Transduction; Source; Structure; Technology; Testing; Tissues; Training; Transgenic Mice; Transgenic Organisms; Translating; Trauma; WNT Signaling Pathway; Work; beta catenin; bioinformatics tool; blastema; bone; career development; cell growth; cell type; conditional knockout; cost; digit regeneration; improved; innovation; insight; laser capture microdissection; limb regeneration; microCT; mouse model; musculoskeletal injury; novel therapeutics; osteogenic; outcome forecast; paracrine; regenerative; response; skeletal disorder; skeletal injury; skills; spatiotemporal; stem; stem cells; transcriptome sequencing; transcriptomics

Project Summary Humans have limited regenerative potential after extensive musculoskeletal injuries, particularly following limb loss. As such, the ability to biologically restore the missing limb will significantly improve the quality of life for millions of amputees. To understand the fundamental mechanisms guiding regeneration of complex musculoskeletal tissues or organs, mouse models of digit amputation have been used to study musculoskeletal regrowth, which occurs in a spatiotemporally controlled manner upon distal digit tip removal. While much progress has been made to elucidate the cell types and growth factors responsible for this natural regenerative response, the exact cellular and molecular mechanisms underlying digit regeneration have yet to be revealed. Recent studies suggest that cells derived from the periosteum participate in bone regrowth in adults, and thus represent a possible source of osteoblast lineage cells. However, it remains unknown to what extent this specific cell population plays a direct role in digit regeneration. We hypothesize that spatiotemporal activation of distinct molecular events after distal digit amputation mediates the activation, proliferation, and/or differentiation of periosteal cells (PCs). To test this hypothesis, we will investigate the spatiotemporal response of PCs after digit amputation using Osx-CreERT2;Ai9 inducible reporter transgenic mice in Aim 1, which will permit lineage tracing of this cell population. Furthermore, we will test the requirement of proliferating PCs during digit regeneration by inducible conditional ablation of replicating PCs using 3.6Col1a1-tk transgenic mice. Finally, we will determine the signaling cues that activate and sustain digit regeneration in Aim 2 using RNA in situ hybridization and tissue-specific RNA-sequencing, with a specific focus on the spatiotemporal distribution of canonical Wnt signaling. By identifying the cells and molecular pathways vital to regeneration, this proposal will open new avenues to therapies that will help restore the biological composition and structure of the lost tissues.

项目摘要 在广泛的肌肉骨骼损伤之后，人类的再生潜力有限，特别是 肢体损失后。因此，生物学恢复缺失的肢体的能力将显着改善 数百万截肢者的生活质量。了解指导再生的基本机制 复杂的肌肉骨骼组织或器官，数字截肢的小鼠模型已用于研究 肌肉骨骼再生，在远端数字尖端去除后以时空控制的方式发生。 尽管已经取得了很大的进步来阐明造成这种自然的细胞类型和生长因素 再生反应，数字再生的确切细胞和分子机制尚未 被揭示。最近的研究表明，源自骨膜的细胞参与了骨再生 成人，因此代表了成骨细胞谱系细胞的可能来源。但是，什么是未知的 该特定细胞种群在数字再生中起着直接的作用。 我们假设远端数字截肢后不同分子事件的时空激活 介导骨膜细胞的激活，增殖和/或分化（PC）。为了检验这一假设，我们 将使用OSX-Creert2; AI9诱导的数字截肢截肢后PC的时空响应进行研究 AIM 1中的记者转基因小鼠，这将允许对该细胞种群进行谱系追踪。此外，我们会的 通过诱导的有条件消融来测试在数字再生过程中增殖PC的需求 PC使用3.6col1a1-TK转基因小鼠。最后，我们将确定激活和维持的信号提示 AIM 2中的数字再生使用RNA使用原位杂交和组织特异性RNA测序，并具有特定的 专注于规范Wnt信号的时空分布。通过识别细胞和分子 这项建议将为疗法开辟新的途径，以帮助恢复该疗法 损失组织的生物组成和结构。