Corneal Reconstruction through an In Situ-Forming Collagen Gel

通过原位形成胶原凝胶进行角膜重建

• 批准号: 10249065
• 负责人: David Myung
• 金额: --
• 依托单位: VETERANS ADMIN PALO ALTO HEALTH CARE SYS
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10249065
• 关键词: Air; Animal Model; Area; Award; Biocompatible Materials; Biological; Blindness; Cadaver; Cells; Chemistry; Cicatrix; Clinical; Collagen; Copper; Cornea; Corneal Diseases; Corneal Injury; Corneal Ulcer; Data; Defect; Development; Disease; Economics; Encapsulated; Engineering; Epithelial; Eye; Eye Injuries; Eye diseases; Foundations; Future; Gel; Goals; Grant; Growth Factor; Immunoassay; In Situ; In Vitro; Keratopathy; Keratoplasty; Lead; Light; Liquid substance; Mechanics; Messenger RNA; Modality; Modeling; Morphology; Myofibroblast; Natural regeneration; Ophthalmologist; Ophthalmology; Optics; Pathologic; Perforation; Performance; Prosthesis; Proteins; Refractory; Research; Risk; Side; Stromal Cells; Structure; Surface; Technology; Testing; Thick; Thinness; Time; Tissue Donors; Tissues; Transplantation; Trauma; Traumatic Brain Injury; Trigeminal nerve structure; Ulcer; Veterans; Vision; Visual Pathways; Visual impairment; Water; Work; biological systems; biomaterial compatibility; catalyst; chronic ulcer; clinical translation; corneal epithelial wound healing; corneal scar; crosslink; density; epithelial wound; high risk; improved; improved outcome; in vivo; novel; point of care; preservation; reconstruction; regenerative; response; restoration; service member; severe injury; sight restoration; skin ulcer; stem cells; tissue support frame; wound

As the dome-shaped, transparent outermost part of the eye, the cornea provides the majority of the focusing power for the visual pathway. When damaged due to severe injury or disease, its normally smooth contour and optical clarity are often lost, resulting in reduced vision and, in many cases, blindness. Restoration of normal corneal structure and function in Service Members and Veterans with vision-compromising corneal injuries and disease is a priority. In spite of the various types of cadaveric corneal transplants that are available, there remains a major clinical need for new modalities to rapidly reconstruct and regenerate corneal tissue after severe injury or disease. We propose to develop a novel, sutureless, corneal tissue substitute that stabilizes deep ulcers, defects, and thinned areas of the cornea. The material is applied to a corneal wound as a viscous liquid, forming a crosslinked, transparent gel within minutes that recreates the smooth, air-cornea interface necessary for clear vision, while also promoting rapid epithelialization. This technology leverages a novel collagen crosslinking modality known as copper-free click chemistry that is bio-orthogonal: it does not react with proteins, cells, or biologic systems of any kind. As such, it can be safely applied to the surface of a wounded cornea without producing toxic side products, and without the need for potentially harmful external catalysts or triggers. We hypothesize that while a bio-orthogonally, in situ-crosslinked, collagen gel alone may promote rapid epithelialization and wound stabilization, its long-term biointegration and transparency will be enhanced by the presence of encapsulated corneal stromal stem cells that can re-model the applied matrix without causing fibrotic changes. We will test this hypothesis by evaluating the in vitro and in vivo performance of the collagen gel with and without encapsulated corneal stromal stem cells. Corneal stromal stem cells are known to secrete factors critical to preserving the transparency of the cornea if they are able to quiescently differentiate into keratocytes rather than myofibroblasts. In preliminary work, we have shown that bio-orthogonally crosslinked collagen gels are able to encapsulate corneal stromal stem cells and facilitate keratocytic morphology, and also support the formation of a multi-layered epithelium ex vivo. Motivated by this data, our first aim is to characterize and control the biological response of corneal tissue to in situ-crosslinked collagen gels in vitro. Our second aim is to evaluate the biointegration and functional performance of in situ- crosslinked collagen gels as a corneal stromal substitute in vivo. This research will increase understanding of a novel class of sutureless, in situ-forming tissue scaffolds to reconstruct corneal tissue. The results from these studies will build the foundational data for a VA Merit Award and future clinical translation of this technology for the benefit of Service Members and Veterans at risk of or suffering from corneal blindness.

作为眼睛的圆顶形透明最外层，角膜提供了大部分的角膜功能。 视觉通路的聚焦能力。当由于严重的伤害或疾病而损坏时， 平滑轮廓和光学清晰度常常丧失，导致视力下降，在许多情况下， 失明眼外伤患者正常角膜结构和功能的恢复 视力受损的角膜损伤和疾病是一个优先事项。尽管有各种各样的尸体 尽管角膜移植是可用的，但仍然存在对新模式的主要临床需求，以快速 在严重损伤或疾病后重建和再生角膜组织。 我们建议开发一种新的，无缝线，角膜组织替代物，稳定深部溃疡，缺损， 以及角膜变薄的区域。该材料作为粘性液体应用于角膜伤口， 几分钟内形成透明的交联凝胶， 清晰的视力，同时也促进快速上皮化。这项技术利用了一种新的胶原蛋白 交联模式称为无铜点击化学，是生物正交的：它不与 蛋白质、细胞或任何种类的生物系统。因此，它可以安全地应用于表面， 受伤的角膜，而不产生有毒的副产品，并且不需要潜在的有害物质， 外部催化剂或触发器。 我们假设，虽然生物正交，原位交联，胶原蛋白凝胶单独可以促进快速 上皮形成和伤口稳定，其长期生物整合和透明度将得到增强 通过包封的角膜基质干细胞的存在， 引起纤维化变化。我们将通过评价体外和体内性能来检验这一假设 有和没有包裹的角膜基质干细胞的胶原凝胶。角膜基质干细胞 如果它们能够分泌对保持角膜透明度至关重要的因子， 静止地分化成角膜细胞而不是肌成纤维细胞。在初步工作中，我们已经表明， 生物正交交联的胶原凝胶能够包封角膜基质干细胞， 促进角质细胞形态，并且还支持离体多层上皮的形成。 受这些数据的启发，我们的首要目标是表征和控制角膜组织的生物反应 体外原位交联胶原凝胶。我们的第二个目标是评估生物整合和功能 原位交联胶原凝胶作为角膜基质替代物在体内的性能。本研究 将增加对一类新型无缝线原位形成组织支架的理解， 角膜组织这些研究的结果将为VA优异奖建立基础数据， 这项技术的未来临床翻译，以造福于有风险或 患有角膜盲症