Stem Cells for Corneal Engineering

角膜工程干细胞

• 批准号: 8103366
• 负责人: JAMES L FUNDERBURGH
• 金额: $ 44.52万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-15 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8103366
• 关键词: Address; Adopted; Adult; Affect; Animal Model; Anterior; Architecture; Biological; Biomedical Engineering; Blindness; Caliber; Cattle; Cell Proliferation; Cell Therapy; Cicatrix; Clinical Trials; Collagen; Confocal Microscopy; Connective Tissue; Cornea; Corneal Opacity; Corneal Stroma; Debridement; Deposition; Development; Effectiveness; Engineering; Epithelial; Esters; Excision; Exhibits; Extracellular Matrix; Eye; Fibroblasts; Fibrosis; Funding; Gel; Gene Expression; Generations; Genetic Models; Goals; Health; Human; Image; Imagery; Immune; Immunologic Markers; In Vitro; Individual; Injection of therapeutic agent; Keratoplasty; Knockout Mice; Laboratories; Lamellar Keratoplasty; Matrix Metalloproteinases; Medical; Modeling; Molecular Profiling; Mus; Natural regeneration; Operative Surgical Procedures; Oryctolagus cuniculus; Phase; Phenotype; Process; Property; Proteoglycan; Protocols documentation; Readiness; Source; Stem cells; Testing; Therapeutic; Thick; Time; Tissue Donors; Tissues; Translations; Transplantation; Urea; Urethane; Vision; Visual impairment; Wound Healing; adult stem cell; base; biodegradable polymer; cell motility; cell water; clinical application; corneal scar; human adult stem cell; human stem cells; in vitro Model; in vivo; in vivo Model; lumican; monolayer; nanofiber; novel; polyurethaneurea; programs; protein expression; repaired; research study; response; restoration; scaffold; second harmonic; therapy development; tissue regeneration; wound

DESCRIPTION (provided by applicant): Corneal blindness affects millions of individuals world-wide and usually can only be treated by transplantation of donated tissue. In many regions of the world donor tissue is not available; in the US, the supply of corneas for transplant is threatened by increasing numbers of eyes with refractive surgeries. The long-term goal of this project is to address corneal blindness by developing therapies based on stem cells. This project has already identified and characterized adult human corneal stromal stem cells (CSSC), which can be expanded in culture while retaining the ability to adopt a keratocyte phenotype and to elaborate abundant stroma-like connective tissue. When CSSC were cultured on a scaffolding of aligned paralel nanofibers of poly(ester urethane)urea (PEUU), a biodegradable polymer, they secreted connective tissue with aligned collagen similar to that of normal corneal stroma. When CSSC were injected into stromas of lumican knockout mice, collagen in the stroma became more organized and corneal transparency was increased. Importantly, human CSSC exhibited an immune privilege in mice, remaining viable for months without immune rejection. The new proposal will test specific hypotheses emanating directly from these exciting findings. Aim 1 documents the process of tissue regeneration by CSSC by testing the predictions that (a) CSSC first remove existing tissue by temporally regulated expression of a specific group of matrix metalloproteinases; (b) after this removal process, CSSC rebuild stromal tissue by deposition of new connective tissue; and (c) this regeneration process can remodel scar tissue similar to that causing most human corneal blindness. Aim 2 combines CSSC with PEUU scaffolding to produce a novel bioengineered tissue and tests the predictions that (a) CSSC monolayers on PEUU nanofiber scaffolding can integrate and function as transparent stromal tissue in mouse corneal transplants; (b) CSSC can be incorporated into multilayered PEUU scaffolding with the thickness and strength of a corneal stroma; and (c) the multilayered constructs can functionally replace stroma after transplantation into rabbit corneas using deep anterior lamellar keratoplasty. The scientific impact of this study will be a demonstration of effectiveness of two novel stem-cell based therapeutic approaches for corneal scarring, indicating a readiness for translation of each to clinical trials. PUBLIC HEALTH RELEVANCE: Corneal blindness is a health problem world-wide. For many individuals with this condition there is no option for restoration of vision. This project will use adult human stem cells to develop therapy for corneal scarring, a major source of blindness. These stem cells can be produced in large numbers, are safe, and do cause tissue rejection. Successful development of these therapies may open new opportunity to restore vision to large numbers of people.

描述（由申请人提供）：角膜失明影响着全世界数百万人，通常只能通过移植捐赠的组织来治疗。世界许多地区无法获得供体组织；在美国，接受屈光手术的眼睛数量不断增加，用于移植的角膜供应受到威胁。该项目的长期目标是通过开发基于干细胞的疗法来解决角膜失明问题。该项目已经鉴定并表征了成人角膜基质干细胞（CSSC），这种细胞可以在培养物中扩增，同时保留采用角膜细胞表型和精心制作丰富的基质样结缔组织的能力。当 CSSC 在聚（酯氨基甲酸酯）脲（PEUU）（一种可生物降解的聚合物）排列的平行纳米纤维支架上培养时，它们分泌出具有与正常角膜基质相似的排列胶原蛋白的结缔组织。当将 CSSC 注射到 lumican 敲除小鼠的基质中时，基质中的胶原蛋白变得更有组织，角膜透明度增加。重要的是，人类 CSSC 在小鼠体内表现出免疫特权，可在数月内保持活力而不会产生免疫排斥。新提案将测试直接源自这些令人兴奋的发现的具体假设。目标 1 通过测试以下预测来记录 CSSC 的组织再生过程：(a) CSSC 首先通过临时调节一组特定基质金属蛋白酶的表达来去除现有组织； (b)在该去除过程之后，CSSC通过沉积新的结缔组织来重建基质组织； (c)这种再生过程可以重塑疤痕组织，类似于导致大多数人类角膜失明的情况。目标 2 将 CSSC 与 PEUU 支架相结合，产生一种新型生物工程组织，并测试以下预测：(a) PEUU 纳米纤维支架上的 CSSC 单层可以在小鼠角膜移植中整合并充当透明基质组织； (b) CSSC可以纳入多层PEUU支架中，其厚度和强度与角膜基质相同； (c)使用深前板层角膜移植术移植到兔角膜后，多层结构可以在功能上替代基质。这项研究的科学影响将证明两种基于干细胞的新型角膜疤痕治疗方法的有效性，表明每种方法都已准备好转化为临床试验。 公共卫生相关性：角膜失明是世界范围内的一个健康问题。对于许多患有这种疾病的人来说，没有恢复视力的选择。该项目将使用成人干细胞开发角膜疤痕的治疗方法，角膜疤痕是导致失明的主要原因。这些干细胞可以大量产生，是安全的，并且确实会引起组织排斥。这些疗法的成功开发可能会为大量人恢复视力带来新的机会。