利用胶原蛋白/氧化石墨烯纳米纤维复合膜为支架的组织工程视网膜色素上皮的研究

Dysfunction of retinal pigment epithelium (RPE) cells and Bruch membrane (BM) will lead to retinal degenerative diseases. However, there is no effective treatment for these diseases. Tissue-engineering RPE transplantation means that RPE cells are cultured on the biofilm (ie, artificial BM) to form functional tissue engineering RPE, which is then transplanted to replace patients’ damaged RPE cells and BM. This is the most promising treatment for retinal degenerative diseases. However, previous artificial BM can not take into account the biocompatibility, permeability and surgical operability, limiting the further application of tissue engineering RPE. In the preliminary work, we found that collagen nanofibrous membrane had good biocompatibility and permeability, and that graphene oxide not only supported the growth of RPE cells but also had excellent mechanical properties. In this study, we plan to prepare collagen/graphene oxide nanofibrous composite membrane by electrospinning. The topological structure, biodegradability and mechanical properties of the artificial BM are studied in vitro. We will culture the RPE cells on the artificial BM to study the growth and morphology of RPE cells. Then the tissue engineering RPE will be transplanted into the subretinal space of light-induced retinal degeneration minipigs to study the biocompatibility and the protection of visual function by tissue engineering RPE. This study is expected to provide a new strategy for the treatment of retinal degenerative diseases.

视网膜色素上皮（RPE）细胞和Bruch膜功能障碍将导致视网膜变性疾病，这类疾病目前缺乏有效治疗措施。组织工程RPE移植是将RPE细胞培养在生物膜（即人工Bruch膜）上，形成有功能的组织工程RPE后再移植，有望替代患者受损的RPE细胞和Bruch膜，是最有前景的治疗方式。但目前研制的人工Bruch膜无法兼顾生物相容性、渗透性和手术操作性，限制了组织工程RPE的进一步应用。前期工作中我们发现，胶原蛋白纳米纤维膜具有良好的生物相容性和渗透性，氧化石墨烯支持RPE细胞的生长还具有极佳的机械性能。本项目拟采用静电纺丝技术制备胶原蛋白/氧化石墨烯纳米纤维复合膜，研究其表面形貌、降解性和机械性能，再将RPE细胞培养在该人工Bruch膜上，检测RPE细胞形态和功能；组织工程RPE移植到光诱导视网膜变性猪的视网膜下腔后，研究其生物相容性和对视功能的保护作用。本研究有望为视网膜变性疾病的治疗提供新策略。

组织工程视网膜色素上皮（RPE）移植是治疗视网膜变性疾病最有前景的方式，但目前研制的人工Bruch膜无法兼顾生物相容性、渗透性和手术操作性，限制了组织工程RPE的进一步应用。本项目探索了人工Bruch膜的制备方法，并以胚胎干细胞来源的RPE细胞（ESC-RPE）为种子细胞，构建出组织工程RPE，并通过体外、体内实验研究了组织工程化RPE的形态、功能、基因表达谱和生物相容性。研究发现，明胶/氧化石墨烯/聚己内酯纳米纤维复合膜具有良好的亲水性、生物相容性和渗透性，支持ESC-RPE细胞生长，可构建有典型形态和功能的组织工程RPE，并且具有良好的力学特性，满足手术操作需要。移植到体内后，未见明显炎症反应，视网膜结构和功能保持良好。本研究具有较好的临床转化前景，有望为视网膜变性疾病的治疗提供新的策略。