Corneal Scar Repair through SPAACKL: Sutureless, Pro-regenerative Anterior Additive Collagen gel KeratopLasty

项目总结/摘要 作为眼睛的圆顶状透明最外层，角膜提供了大部分聚焦 视觉通路的能量当它由于严重的伤害或疾病而受损时，疤痕往往会出现， 导致视力下降，并且在许多情况下导致失明。尽管有各种类型的角膜移植 尽管现有的治疗方法，但临床上仍然需要新的方法来恢复疤痕的透明度。 没有捐赠组织的角膜，这在世界范围内都是短缺的。角膜间充质基质细胞（c-MSCs） MSC）对角膜瘢痕形成和伤口愈合具有已知的治疗效果，但最佳的方法是 他们的眼睛有什么好处还有待确定。我们正在开发免缝合，促再生， 前添加剂胶原凝胶角膜成形术（SPAACKL），一种去除和替代致盲的手术 角膜瘢痕与含有c-MSC的透明基质样凝胶基质。角膜瘢痕切除后 组织，将材料作为c-MSC的粘性液体悬浮液施加到缺损，形成交联的， 透明的细胞化基质替代品，不仅在几分钟内重建光滑的表面， 这是清晰视力所必需的，而且还促进快速上皮再生。这项技术利用了 被称为无铜点击化学的交联技术是生物正交的：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角膜伤口， 在c-MSC周围不产生有毒副产物，并且不需要光能、催化剂或 加速器我们的中心假设是，生物正交交联可以提高再生 与特异性较低的c-MSC相比，c-MSC通过保留其包封货物的生物活性而具有的益处 目前在角膜手术中使用的交联化学。在初步工作中，我们 证明生物正交交联凝胶支持包囊基质细胞的生长， 已经证明了这些细胞基质复合材料的再生能力，以支持快速，多层 离体和体内的上皮形成。受这些数据的启发，我们的第一个目标是检验假设， 基质硬度、组成和交联化学影响c-MSCs的活力和pro-MSCs的分泌。 再生因子我们的第二个目的是检验包裹的c-MSCs发挥其促增殖作用的假设。 主要通过旁分泌信号传导对角膜上皮的再生影响。我们的第三个目标是 评价生物正交交联水凝胶递送治疗性货物的能力， 通过体内角膜切除术模型的上皮和基质再生。这项研究将建立 最终临床转化为治疗角膜盲的新方法的基础数据， 用于缝合、光能或尸体供体组织，并有可能在某一天帮助患者避免 需要传统的角膜移植。

PROJECT SUMMARY/ABSTRACT As the dome-shaped, transparent outermost part of the eye, the cornea provides the majority of the focusing power for the visual pathway. When it is damaged due to severe injury or disease, scarring often ensues, resulting in reduced vision and, in many cases, blindness. In spite of the various types of corneal transplants that are available, there remains a major clinical need for new modalities to restore transparency to scarred corneas without donor tissue, which is in short supply worldwide. Corneal mesenchymal stromal cells (c- MSCs) have known therapeutic effects on corneal scarring and wound healing, but the optimal way to deliver their benefits to the eye have yet to be determined. We are developing Sutureless, Pro-regenerative, Anterior Additive Collagen gel KeratopLasty (SPAACKL), a procedure that removes and replaces blinding corneal scars with a transparent, stroma-like gel matrix containing c-MSCs. After removal of corneal scar tissue, the material is applied to the defect as a viscous liquid suspension of c-MSCs, forming a crosslinked, transparent cellularized stromal substitute within minutes that not only recreates the smooth surface necessary for clear vision but also promotes rapid re-epithelialization. This technology leverages a crosslinking technology 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 a corneal wound and around c-MSCs without producing toxic side products, and without the need for light energy, catalysts or accelerators. Our central hypothesis is that bio-orthogonal crosslinking can improve the regenerative benefits of c-MSCs by preserving the bioactivity of its encapsulated cargo compared to less specific crosslinking chemistries that are used currently in corneal surgery. In preliminary work, we have demonstrated that bio-orthogonally crosslinked gels support the growth of encapsulated stromal cells and have demonstrated the regenerative capacity of these cell-matrix composites to support rapid, multi-layered epithelialization both ex vivo and in vivo. Motivated by this data, our first aim is to test the hypothesis that matrix stiffness, composition, and crosslinking chemistry influence c-MSCs’ viability and secretion of pro- regenerative factors. Our second aim is to test the hypothesis that encapsulated c-MSCs exert their pro- regenerative influence on the corneal epithelium primarily through paracrine signaling. Our third aim is to evaluate the ability of bio-orthogonally crosslinked hydrogels to deliver therapeutic cargo that enhances epithelial and stromal regeneration through an in vivo keratectomy model. This research will build the foundational data for eventual clinical translation of a new way to treat corneal blindness without the need for sutures, light energy, or cadaveric donor tissue, and has the potential to one day help patients avoid the need for a traditional corneal transplant.