Wilson Samantha L, El Haj Alicia J, Yang Ying
Institute for Science and Technology in Medicine, School of Medicine, Keele University, Staffordshire, ST4 7QB, UK.
J Funct Biomater. 2012 Sep 18;3(3):642-87. doi: 10.3390/jfb3030642.
Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.
角膜结构在架构上高度有序且统一，具有结构和功能的整合，这介导了透明度和视力。疾病和损伤是导致失明的第二大常见原因，全球超过1000万人受其影响。90%的失明是永久性的，原因是瘢痕形成和血管化。由纤维化细胞反应引起的瘢痕形成可愈合组织，但无法恢复透明度。控制角膜细胞的激活和分化是抑制和预防纤维化的关键。眼科手术技术不断发展以保护和恢复视力，但角膜消退和瘢痕形成往往是有害的副作用，且缺乏长期持续的随访研究或结果不乐观。合适的角膜模型可能会减少角膜移植的需求，因为目前没有足够数量的合适组织来满足需求。用于角膜假体的合成光学材料正在研发中，尽管由于植入并发症和高排斥率，其临床应用有限。组织工程角膜提供了一种替代方案，它更紧密地模拟天然角膜的形态、生理和生物力学特性。然而，复制天然胶原纤维组织并保留防止瘢痕样组织形成的基质细胞表型仍然是一个挑战。正在研究仔细操控培养环境，以确定一个模拟天然细胞外基质组织并刺激角膜细胞迁移和生成的合适环境。
