Abstract:
As the outermost layer of the eye, the cornea is vulnerable to physical and chemical trauma, which can result in loss of transparency and lead to corneal blindness. Given the global corneal donor shortage, there is an unmet need for biocompatible corneal substitutes that have high transparency, mechanical integrity and regenerative potentials. Herein we engineered a dual-layered collagen vitrigel containing biomimetic synthetic Bowman\'s membrane (sBM) and stromal layer (sSL). The sBM supported rapid epithelial cell migration, maturation and multilayer formation, and the sSL containing tissue-derived extracellular matrix (ECM) microparticles presented a biomimetic lamellar ultrastructure mimicking the native corneal stroma. The incorporation of tissue-derived microparticles in sSL layer significantly enhanced the mechanical properties and suturability of the implant without compromising the transparency after vitrification. In vivo performance of the vitrigel in a rabbit anterior lamellar keratoplasty model showed full re-epithelialization within 14 days and integration of the vitrigel with the host tissue stroma by day 30. The migrated epithelial cells formed functional multilayer with limbal stem cell marker p63 K14 expressed in the lower layer, epithelial marker K3 and K12 expressed through the layers and tight junction protein ZO-1 expressed by the multilayers. Corneal fibroblasts migrated into the implants to facilitate host/implant integration and corneal stromal regeneration. In summary, these results suggest that the multi-functional layers of this novel collagen vitrigel exhibited significantly improved biological performance as corneal substitute by harnessing a fast re-epithelialization and stromal regeneration potential.
摘要:
作为眼睛的最外层,角膜容易受到物理和化学创伤,这可能导致透明度丧失并导致角膜失明。鉴于全球角膜供体短缺,对具有高透明度的生物相容性角膜替代品的需求尚未满足,机械完整性和再生潜力。在这里,我们设计了含有仿生合成Bowman膜(sBM)和基质层(sSL)的双层胶原蛋白玻璃化凝胶。sBM支持快速上皮细胞迁移,成熟和多层形成,包含组织来源的细胞外基质(ECM)微粒的sSL呈现模拟天然角膜基质的仿生层状超微结构。在sSL层中掺入组织来源的微粒显著增强了植入物的机械性能和可缝合性,而不损害玻璃化后的透明度。玻璃化胶在兔前板层角膜移植术模型中的体内表现在14天内显示出完全的上皮再形成,并且到第30天玻璃化胶与宿主组织基质整合。迁移的上皮细胞形成功能多层,角膜缘干细胞标志物p63K14在下层表达,上皮标记K3和K12通过层表达,而紧密连接蛋白ZO-1通过多层表达。角膜成纤维细胞迁移到植入物中以促进宿主/植入物整合和角膜基质再生。总之,这些结果表明,这种新型胶原蛋白玻璃化凝胶的多功能层通过利用快速的上皮再形成和基质再生潜力,作为角膜替代品表现出显著改善的生物学性能。