Development of cell-free approaches to the treatment of limbal stem cell deficiency

开发治疗角膜缘干细胞缺陷的无细胞方法

• 批准号: 10737842
• 负责人: Yuzuru Sasamoto
• 金额: $ 24.9万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10737842
• 关键词: ATP-Binding Cassette Transporters; Address; Admixture; Allogenic; Area; Autologous; Autologous Transplantation; BMP2 gene; Bilateral; Binding; Blindness; CAV1 gene; Cell Maintenance; Cell Separation; Cell Survival; Cells; Characteristics; Clinical; Clinical Trials; Contralateral; Cornea; Development; Disease model; Doctor of Philosophy; Experimental Models; Eye; FDA approved; FGF7 gene; FGFR2 gene; Fibroblast Growth Factor; Genes; Genetic Engineering; Goals; Homologous Transplantation; Human; In Vitro; Instruction; Maintenance; Mentorship; Modeling; Molecular; Mus; Natural regeneration; Ophthalmologist; Ophthalmology; Organ; Pathway interactions; Patients; Phase; Phenotype; Receptor Protein-Tyrosine Kinases; Regenerative Medicine; Regulation; Research; Research Personnel; Role; Signal Pathway; Signal Transduction; Stem Cell Development; Stem cell transplant; Testing; Therapeutic; Tissues; Topical application; Training; Undifferentiated; Vocational Guidance; cell regeneration; clinical training; clinical translation; conjunctiva; corneal epithelium; experience; fascinate; improved; in vivo; induced pluripotent stem cell; interest; limbal; member; morphogens; novel; pre-clinical; recruit; regeneration potential; restoration; single-cell RNA sequencing; stem cell biology; stem cell biomarkers; stem cell homeostasis; stem cell niche; stem cell population; stem cell self renewal; stem cells; success; therapeutic evaluation

PROJECT SUMMARY (See instructions): Limbal stem cells (LSCs) give rise to the entire corneal epithelium and are known to reside in the border area between the cornea and conjunctiva called limbus. Loss of LSCs or destruction of the LSC niche can result in Limbal Stem Cell Deficiency (LSCD) – a common cause of vision loss in the world. While transplantation of the autologous limbal tissues removed from the contralateral eye can cure patients with unilateral LSCD, bilateral LSCD patients have no autologous limbal tissues available. These patients often require transplantation of allogeneic donor limbal grafts; however, their success is highly variable. Moreover, the worldwide corneal donor shortage poses significant challenges for the availability of allogeneic LSCs for the treatment of bilateral LSCD patients. Thus, the overarching goal of this project is to develop cell-free LSCD therapies through the discovery of novel mechanisms of LSC maintenance and regeneration. Our lab has discovered an ATP-binding cassette (ABC) superfamily member B5 (ABCB5) as a novel LSC marker. ABCB5-positive LSCs isolated from human donors were capable of the long-term corneal restoration in pre-clinical LSCD models. Clinical trials are currently on the way to address the therapeutic potential of this stem cell population in human patients. Our most recent studies aimed to explore the cellular hierarchy within ABCB5-positive LSCs using single-cell RNA-sequencing revealed a novel LSC subpopulation that could be differentiated from the other LSC clusters by low expression levels of the cornea-specific genes. Here we hypothesized that this subpopulation possesses the most primitive stem cell characteristics with the highest regenerative potential. Further in-depth analyses revealed that these cells preferentially expressed the molecules involved in FGF, BMP, and AXL signaling cascades. We posit that these molecular pathways are essential for the maintenance of the undifferentiated LSC phenotype and can be employed for de-novo LSC induction and restoration of the LSC niche in the setting of bilateral LSCD. The two Aims of this proposal will: mechanistically dissect the role of FGF7, BMP2 and AXL in the LSC maintenance using murine and human genetically engineered experimental models (Aim 1) and will test the therapeutic potential of targeting these pathways for the treatment of LSCD in pre-clinical murine disease models (Aim 2). Successful completion of this study will further advance our understanding of LSC development, maintenance, and regulation with significant implications for clinical translation

项目总结（见说明）： 角膜缘干细胞（LSC）产生整个角膜上皮，并且已知存在于边缘区域 在角膜和结膜之间的区域称为利姆布斯。LSC的丧失或LSC生态位的破坏可导致角膜缘炎。 干细胞缺乏症（LSCD）-世界上视力丧失的常见原因。在移植自体 对侧眼角膜缘组织切除可治愈单侧LSCD患者，双侧LSCD患者 没有自体角膜缘组织可用这些患者通常需要同种异体角膜缘移植 移植;然而，它们的成功是高度可变的。此外，世界范围内角膜供体的短缺造成了严重的 同种异体LSC用于治疗双侧LSCD患者的可用性面临挑战。因此， 该项目的目标是通过发现LSC的新机制来开发无细胞LSCD疗法 维护和再生。我们的实验室发现了一个ATP结合盒（ABC）超家族成员B5 （ABCB 5）作为新的LSC标记物。从人供体分离的ABCB 5阳性LSC能够长期维持其功能。 临床前LSCD模型中的角膜修复。目前正在进行临床试验， 干细胞在人类患者中的潜力。我们最近的研究旨在探索细胞 使用单细胞RNA测序在ABCB 5阳性LSC内的分级显示了一种新的LSC亚群， 可以通过角膜特异性基因的低表达水平与其他LSC簇区分开。这里我们 假设这个亚群具有最原始的干细胞特征， 再生潜力进一步的深入分析显示，这些细胞优先表达这些分子， 参与FGF、BMP和AXL信号级联。我们认为这些分子途径对于 维持未分化的LSC表型，并可用于从头LSC诱导和恢复 的LSC生态位在设置双边LSCD。本提案的两个目标是： 使用鼠和人基因工程实验，在LSC维持中FGF 7、BMP 2和AXL的表达 模型（目标1），并将测试靶向这些途径治疗LSCD的治疗潜力， 临床前鼠疾病模型（Aim 2）。这项研究的成功完成将进一步推动我们的 了解LSC的发展，维持和调节，对临床翻译具有重要意义