Engineering Biomimetic Corneal Constructs

工程仿生角膜结构

• 批准号: 7936910
• 负责人: Jeffrey W Ruberti
• 金额: $ 38.03万
• 依托单位: NORTHEASTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-01 至 2012-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7936910
• 关键词: Artificial skin; Ascorbic Acid; Basic Science; Biochemical; Biochemistry; Biocompatible Materials; Biology; Biomechanics; Biomedical Engineering; Biomimetics; Bioreactors; Caliber; Cell Communication; Cells; Chemicals; Chemistry; Cicatrix; Clinical; Collagen; Collagen Fibril; Collagen Type V; Complex; Connective Tissue; Cornea; Cues; Deposition; Development; Disease; Endothelium; Engineering; Environment; Epithelium; Event; Fibroblasts; Freezing; Future; Gel; Generations; Genetic; Glycosaminoglycans; Goals; Human; Hybrids; Image; In Vitro; Intelligence; Investigation; Keratoplasty; Kinetics; Laser In Situ Keratomileusis; Life; Liquid substance; Mechanical Stimulation; Mechanics; Mesenchymal; Mesenchymal Stem Cells; Methods; Microscope; Microscopy; Morbidity - disease rate; Morphology; Operative Surgical Procedures; Optics; Outcome; Patients; Periodicity; Physical condensation; Population; Principal Investigator; Printing; Procedures; Production; Property; Proteoglycan; Refractory; Regenerative Medicine; Research; Resolution; Reverse Transcriptase Polymerase Chain Reaction; Role; Signal Transduction; Solutions; Stem Cell Research; Stem cells; Stromal Cells; Structure; System; Testing; Time; Tissue Donors; Tissue Engineering; Tissues; Umbilical Cord Blood; United States; alternative treatment; base; cell motility; fibrillogenesis; implantation; improved; in vivo; insight; light transmission; liquid crystal; meetings; mimetics; model development; monomer; programs; proteoglycan core protein; public health relevance; response; scaffold; stem; success; triple helix

DESCRIPTION (provided by applicant): Every year in the United States, over 33,000 corneal transplants are performed. The success rate for this procedure is fairly high (90% after two years) and although current access to donor tissue is adequate, the quality of tissue varies significantly which influences surgical outcomes. In addition, the proliferation of LASIK procedures, which disqualifies a cornea for transplantation, threatens to reduce the availability of donor corneas in the near future. In recent years, laudable attempts have been made to produce corneal equivalents by tissue engineering. These constructs have proven the concept that three layers of cells, resembling the epithelium, keratocytes and endothelium may be cultured into a collagen matrix. However, such constructs have only met with limited success because the stromal matrix, which provides the cornea with its unique (and critically important) mechanical and optical properties, has not been reproduced. Randomly oriented collagen gels, which represent the typical starting point for tissue engineered corneas, are not likely to be strong enough or clear enough for clinical use. In addition, expecting a significant in vivo remodeling response to integrate a partially functioning artificial cornea is not acceptable. The artificial construct should be functional at the time of implantation. For these reasons, we propose a stromal-centric approach toward the generation of an artificial cornea. We start by investigating precisely how fibroblastic cells produce organized tissue in vitro by tracking human fibroblasts live as they produce matrix on a long-term live imaging culture system. Then by combining bioengineering, biology, biomechanics and biochemistry an attempt will be made to produce biomimetic stromal lamellae (the building blocks for an artificial cornea). The method entails using the intelligence already "encoded" into the collagen triple helix which produces organized arrays of fibrils simply by concentrating the monomers to induce liquid crystalline structure formation and fibrillogenesis. The resulting organized arrays of fibrils will be used as starting point for comprehensive investigation into the role of matrix molecules on collagen fibril morphology and spacing. Once our arrays are well-characterized, human corneal fibroblasts and human cord blood derived stem cells will be seeded into them and exposed to mechanical stimulation. We expect to induce differentiation in both populations of cells. Completion of this application will provide insight both to the basic science of understanding corneal stromal development and to achieving our ultimate goal, which is the ex vivo generation of a functional, biomimetic artificial cornea from natural components. PUBLIC HEALTH RELEVANCE: Completion of this application will provide insight both to the basic science of understanding corneal stromal development and to achieving our ultimate goal, which is the ex vivo generation of a functional, biomimetic artificial cornea from natural components. Given recent advances in biomaterials engineering and stem cell research (which are combined in this application) we expect to ultimately enhance the ability of clinicians to offer patients with significant morbidity viable alternative treatment options based on engineered tissue.

描述（申请人提供）：每年在美国进行超过33,000次角膜移植。该过程的成功率相当高（两年后90％），尽管目前获得供体组织的访问足够，但组织质量差异很大，这会影响手术结果。此外，LASIK程序的扩散是取消角膜进行移植的资格，威胁要在不久的将来降低捐赠者角膜的可用性。近年来，已经为通过组织工程制作角膜当量而值得称赞的尝试。这些结构证明了这样一个概念，即三层细胞，类似于上皮，角膜细胞和内皮，可以培养为胶原基质。但是，这种构建体仅取得了有限的成功，因为尚未再现了角膜的基质基质（基质基质）独特（非常重要）的机械和光学特性。随机定向的胶原蛋白凝胶代表了组织工程角膜的典型起点，不太可能足够强或足够清除临床使用。此外，预计不可接受的一部分功能的人造角膜可以产生重要的体内重塑反应以整合部分功能。人工结构应在植入时起作用。由于这些原因，我们提出了一种以基于基础的人造角膜来产生的基于基础的方法。我们首先研究成纤维细胞如何通过跟踪人成纤维细胞在长期实时成像培养系统上产生矩阵时如何在体外产生有组织的组织。然后，通过将生物工程，生物学，生物力学和生物化学结合起来，将尝试产生仿生基质层状薄片（人造角膜的基础）。该方法需要使用已经“编码”到胶原蛋白三重螺旋中的智能，该螺旋螺旋仅通过浓缩单体诱导液晶结构形成和原纤维生成而产生有组织的原纤维阵列。所得的原纤维阵列将用作对基质分子在胶原原纤维形态和间距中的作用进行全面研究的起点。一旦我们的阵列被充分表征，人角膜成纤维细胞和人脐带血细胞将被播种到它们中，并暴露于机械刺激中。我们期望在两个细胞种群中诱导分化。该应用程序的完成将为了解角膜基质发育的基础科学提供洞察力，并实现我们的最终目标，这是从天然成分的实用，仿生的人造角膜的实体产生。公共卫生相关性：完成本应用的完成将为了解角膜基质发展的基础科学和实现我们的最终目标提供洞察力，这是从天然成分中的功能性，仿生的人造角膜。鉴于生物材料工程和干细胞研究的最新进展（在本应用中结合在一起），我们希望最终增强临床医生为基于工程组织提供显着发病可行替代治疗选择的患者的能力。