Recent Advances in Biosynthetic Corneal Substitutes
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Purpose of Review
Regeneration of the corneal epithelium and endothelium has been achieved, but regeneration of the corneal stroma has not, because it has several remarkable properties, including high tensile strength, thrust resistance, and high transparency. We introduce several biosynthetic approaches to creating stromal substitutes closely resembling the native human corneal stroma are currently being studied.
Currently, there are five approaches to regenerate corneal stroma: (1) decellularization, (2) the use of human recombinant collagen (HRC), (3) optical clarification (and lamination), (4) cell-based regeneration, and (5) organoid generation with induced pluripotent stem (iPS) cells.
Immediate next steps for this area of research include clinical trials of decellularized stromal scaffolds created from porcine corneas or RHC. While these methods have both advantages and disadvantages, their refinement and clinical use, as well as the use of other methods, promise to lead to the continuing development of new approaches.
KeywordsCorneal substitutes Decellularization Human recombinant collagen Optical clarification Cell-based regeneration Organoid generation
Compliance with Ethical Standards
Conflict of Interest
Shunji Yokokura and Yuji Tanaka declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article contains studies with human and animals. These studies followed the tenets of the Declaration of Helsinki and all study protocols were approved by the Institutional Ethics Committees of Tohoku University hospital
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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