University of Antwerp, Ophthalmology, Visual Optics and Visual Rehabilitation, Universiteitsplein 1, Building T4, 2610 Wilrijk, Belgium.
University of Antwerp, Ophthalmology, Visual Optics and Visual Rehabilitation, Universiteitsplein 1, Building T4, 2610 Wilrijk, Belgium; Department of Ophthalmology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium.
Acta Biomater. 2018 Mar 15;69:31-41. doi: 10.1016/j.actbio.2018.01.023. Epub 2018 Feb 1.
Corneal blindness is traditionally treated by transplantation of a donor cornea, or in severe cases by implantation of an artificial cornea or keratoprosthesis. Due to severe donor shortages and the risks of complications that come with artificial corneas, tissue engineering in ophthalmology has become more focused on regenerative strategies using biocompatible materials either with or without cells. The stroma makes up the bulk of the corneal thickness and mainly consists of a tightly interwoven network of collagen type I, making it notoriously difficult to recreate in a laboratory setting. Despite the challenges that come with corneal stromal tissue engineering, there has recently been enormous progress in this field. A large number of research groups are working towards developing the ideal biomimetic, cytocompatible and transplantable stromal replacement. Here we provide an overview of the approaches directed towards tissue engineering the corneal stroma, from classical collagen gels, films and sponges to less traditional components such as silk, fish scales, gelatin and polymers. The perfect stromal replacement has yet to be identified and future research should be directed at combined approaches, in order to not only host native stromal cells but also restore functionality.
In the field of tissue engineering and regenerative medicine in ophthalmology the focus has shifted towards a common goal: to restore the corneal stroma and thereby provide a new treatment option for patients who are currently blind due to corneal opacification. Currently the waiting lists for corneal transplantation include more than 10 million patients, due to severe donor shortages. Alternatives to the transplantation of a donor cornea include the use of artificial cornea, but these are by no means biomimetic and therefore do not provide good outcomes. In recent years a lot of work has gone into the development of tissue engineered scaffolds and other biomaterials suitable to replace the native stromal tissue. Looking at all the different approaches separately is a daunting task and up until now there was no review article in which every approach is discussed. This review does include all approaches, from classical tissue engineering with collagen to the use of various alternative biomaterials and even fish scales. Therefore, this review can serve as a reference work for those starting in the field and but also to stimulate collaborative efforts in the future.
角膜盲传统上通过移植供体角膜来治疗，或者在严重情况下通过植入人工角膜或角膜假体来治疗。由于供体严重短缺，以及人工角膜带来的并发症风险，眼科组织工程越来越注重使用具有生物相容性的材料的再生策略，这些材料可以单独使用，也可以与细胞一起使用。基质构成了角膜厚度的大部分，主要由紧密交织的 I 型胶原网络组成，因此在实验室环境中很难重现。尽管角膜基质组织工程面临挑战，但该领域最近取得了巨大进展。大量研究小组正在努力开发理想的仿生、细胞相容和可移植的基质替代品。在这里，我们概述了用于组织工程角膜基质的方法，从经典的胶原凝胶、薄膜和海绵到不太传统的成分，如丝、鱼鳞、明胶和聚合物。理想的基质替代品尚未被发现，未来的研究应该针对联合方法，不仅要容纳天然基质细胞，还要恢复功能。
在眼科组织工程和再生医学领域，重点已经转移到一个共同的目标上：恢复角膜基质，从而为目前因角膜混浊而失明的患者提供新的治疗选择。目前，由于供体严重短缺，角膜移植的候补名单上有超过 1000 万名患者。供体角膜移植的替代方法包括使用人工角膜，但这些方法都不是仿生的，因此不能提供良好的效果。近年来，人们投入了大量精力开发适合替代天然基质组织的组织工程支架和其他生物材料。单独研究所有不同的方法是一项艰巨的任务，到目前为止，还没有一篇综述文章讨论过所有的方法。这篇综述确实包括了所有的方法，从经典的胶原组织工程到各种替代生物材料的使用，甚至包括鱼鳞。因此，这篇综述可以作为该领域初学者的参考资料，也可以为未来的合作努力提供启发。
